[Feature]add MT2731_MP2_MR2_SVN388 baseline version

Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/connectivity/gps/gps_hal/Android.mk b/src/connectivity/gps/gps_hal/Android.mk
new file mode 100644
index 0000000..9956a5a
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/Android.mk
@@ -0,0 +1,84 @@
+# Copyright Statement:
+#
+# This software/firmware and related documentation ("MediaTek Software") are
+# protected under relevant copyright laws. The information contained herein
+# is confidential and proprietary to MediaTek Inc. and/or its licensors.
+# Without the prior written permission of MediaTek inc. and/or its licensors,
+# any reproduction, modification, use or disclosure of MediaTek Software,
+# and information contained herein, in whole or in part, shall be strictly prohibited.
+#
+# MediaTek Inc. (C) 2016. All rights reserved.
+#
+# BY OPENING THIS FILE, RECEIVER HEREBY UNEQUIVOCALLY ACKNOWLEDGES AND AGREES
+# THAT THE SOFTWARE/FIRMWARE AND ITS DOCUMENTATIONS ("MEDIATEK SOFTWARE")
+# RECEIVED FROM MEDIATEK AND/OR ITS REPRESENTATIVES ARE PROVIDED TO RECEIVER ON
+# AN "AS-IS" BASIS ONLY. MEDIATEK EXPRESSLY DISCLAIMS ANY AND ALL WARRANTIES,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NONINFRINGEMENT.
+# NEITHER DOES MEDIATEK PROVIDE ANY WARRANTY WHATSOEVER WITH RESPECT TO THE
+# SOFTWARE OF ANY THIRD PARTY WHICH MAY BE USED BY, INCORPORATED IN, OR
+# SUPPLIED WITH THE MEDIATEK SOFTWARE, AND RECEIVER AGREES TO LOOK ONLY TO SUCH
+# THIRD PARTY FOR ANY WARRANTY CLAIM RELATING THERETO. RECEIVER EXPRESSLY ACKNOWLEDGES
+# THAT IT IS RECEIVER'S SOLE RESPONSIBILITY TO OBTAIN FROM ANY THIRD PARTY ALL PROPER LICENSES
+# CONTAINED IN MEDIATEK SOFTWARE. MEDIATEK SHALL ALSO NOT BE RESPONSIBLE FOR ANY MEDIATEK
+# SOFTWARE RELEASES MADE TO RECEIVER'S SPECIFICATION OR TO CONFORM TO A PARTICULAR
+# STANDARD OR OPEN FORUM. RECEIVER'S SOLE AND EXCLUSIVE REMEDY AND MEDIATEK'S ENTIRE AND
+# CUMULATIVE LIABILITY WITH RESPECT TO THE MEDIATEK SOFTWARE RELEASED HEREUNDER WILL BE,
+# AT MEDIATEK'S OPTION, TO REVISE OR REPLACE THE MEDIATEK SOFTWARE AT ISSUE,
+# OR REFUND ANY SOFTWARE LICENSE FEES OR SERVICE CHARGE PAID BY RECEIVER TO
+# MEDIATEK FOR SUCH MEDIATEK SOFTWARE AT ISSUE.
+#
+# The following software/firmware and/or related documentation ("MediaTek Software")
+# have been modified by MediaTek Inc. All revisions are subject to any receiver's
+# applicable license agreements with MediaTek Inc.
+
+ifeq ($(BOARD_GPS_LIBRARIES), true)
+LOCAL_PATH := $(call my-dir)
+
+# HAL module implemenation, not prelinked and stored in
+# hw/<OVERLAY_HARDWARE_MODULE_ID>.<ro.product.board>.so
+include $(CLEAR_VARS)
+
+LOCAL_MODULE_RELATIVE_PATH := hw
+LOCAL_SHARED_LIBRARIES := \
+					liblog \
+					libcutils \
+					libhardware
+
+LOCAL_HEADER_LIBRARIES := libcutils_headers
+
+LOCAL_C_INCLUDES += \
+      $(LOCAL_PATH)/inc \
+      $(TOP)/hardware/libhardware/include \
+      $(TOP)/system/core/include \
+      $(TOP)/system/core/libcutils/include
+
+LOCAL_SRC_FILES += \
+	    src/hal2mnl_interface.c \
+		src/hal_mnl_interface_common.c \
+		src/data_coder.c \
+		src/mtk_lbs_utility.c \
+		src/agpsinf.c \
+		src/gpshal.c \
+		src/gpshal_worker.c \
+		src/gfchal_mnl_interface.c \
+		src/geofenceinf.c \
+  		src/mtk_auto_log.c \
+
+ifeq ($(MTK_GPS_CHIP),MTK_GPS_MT3337)
+LOCAL_SRC_FILES += \
+            src/gpsinf3337.c
+else
+LOCAL_SRC_FILES += \
+            src/gpsinf.c
+endif
+
+LOCAL_CFLAGS += -D__ANDROID_OS__
+
+LOCAL_MODULE := gps.$(TARGET_BOARD_PLATFORM)
+LOCAL_PROPRIETARY_MODULE := true
+LOCAL_MODULE_OWNER := mtk
+LOCAL_MODULE_TAGS := optional
+
+include $(BUILD_SHARED_LIBRARY)
+endif
diff --git a/src/connectivity/gps/gps_hal/LICENSE b/src/connectivity/gps/gps_hal/LICENSE
new file mode 100644
index 0000000..77f59ed
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/LICENSE
@@ -0,0 +1,31 @@
+Copyright Statement:
+
+This software/firmware and related documentation ("MediaTek Software") are
+protected under relevant copyright laws. The information contained herein is
+confidential and proprietary to MediaTek Inc. and/or its licensors. Without
+the prior written permission of MediaTek inc. and/or its licensors, any
+reproduction, modification, use or disclosure of MediaTek Software, and
+information contained herein, in whole or in part, shall be strictly
+prohibited.
+
+MediaTek Inc. (C) 2015. All rights reserved.
+
+BY OPENING THIS FILE, RECEIVER HEREBY UNEQUIVOCALLY ACKNOWLEDGES AND AGREES
+THAT THE SOFTWARE/FIRMWARE AND ITS DOCUMENTATIONS ("MEDIATEK SOFTWARE")
+RECEIVED FROM MEDIATEK AND/OR ITS REPRESENTATIVES ARE PROVIDED TO RECEIVER
+ON AN "AS-IS" BASIS ONLY. MEDIATEK EXPRESSLY DISCLAIMS ANY AND ALL
+WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED
+WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR
+NONINFRINGEMENT. NEITHER DOES MEDIATEK PROVIDE ANY WARRANTY WHATSOEVER WITH
+RESPECT TO THE SOFTWARE OF ANY THIRD PARTY WHICH MAY BE USED BY,
+INCORPORATED IN, OR SUPPLIED WITH THE MEDIATEK SOFTWARE, AND RECEIVER AGREES
+TO LOOK ONLY TO SUCH THIRD PARTY FOR ANY WARRANTY CLAIM RELATING THERETO.
+RECEIVER EXPRESSLY ACKNOWLEDGES THAT IT IS RECEIVER'S SOLE RESPONSIBILITY TO
+OBTAIN FROM ANY THIRD PARTY ALL PROPER LICENSES CONTAINED IN MEDIATEK
+SOFTWARE. MEDIATEK SHALL ALSO NOT BE RESPONSIBLE FOR ANY MEDIATEK SOFTWARE
+RELEASES MADE TO RECEIVER'S SPECIFICATION OR TO CONFORM TO A PARTICULAR
+STANDARD OR OPEN FORUM. RECEIVER'S SOLE AND EXCLUSIVE REMEDY AND MEDIATEK'S
+ENTIRE AND CUMULATIVE LIABILITY WITH RESPECT TO THE MEDIATEK SOFTWARE
+RELEASED HEREUNDER WILL BE, AT MEDIATEK'S OPTION, TO REVISE OR REPLACE THE
+MEDIATEK SOFTWARE AT ISSUE, OR REFUND ANY SOFTWARE LICENSE FEES OR SERVICE
+CHARGE PAID BY RECEIVER TO MEDIATEK FOR SUCH MEDIATEK SOFTWARE AT ISSUE.
diff --git a/src/connectivity/gps/gps_hal/Makefile.am b/src/connectivity/gps/gps_hal/Makefile.am
new file mode 100644
index 0000000..a7dc7af
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/Makefile.am
@@ -0,0 +1,29 @@
+AUTOMAKE_OPTIONS=foreign subdir-objects
+lib_LTLIBRARIES = libgpshal.la
+
+libgpshal_la_SOURCES =  src/hal2mnl_interface.c \
+		src/hal_mnl_interface_common.c \
+		src/data_coder.c \
+		src/mtk_lbs_utility.c \
+		src/agpsinf.c \
+		src/gpshal.c \
+		src/gpshal_worker.c \
+		src/gfchal_mnl_interface.c \
+		src/geofenceinf.c \
+  		src/mtk_auto_log.c \
+  		src/gpsinf.c
+
+AM_CFLAGS = -Iinc \
+		-Iinc/hardware \
+		-Ihardware
+
+include_HEADERS = hardware/gps.h \
+		inc/hardware/gps_mtk.h \
+		hardware/gps_internal.h \
+		inc/hal_mnl_interface_common.h \
+		inc/mtk_lbs_utility.h \
+		inc/hal2mnl_interface.h
+
+libgpshal_la_LIBADD = -lrt
+
+DEFS+=-D__LINUX_OS__ -DMTK_GPS_DATA_PATH="\"/usr/share/gps/\""
diff --git a/src/connectivity/gps/gps_hal/NOTICE b/src/connectivity/gps/gps_hal/NOTICE
new file mode 100644
index 0000000..7868067
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/NOTICE
@@ -0,0 +1,23 @@
+ * Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>.

+ * Copyright (C) 1998 - 2013, Daniel Stenberg, <daniel@haxx.se>.

+ * Copyright (C) 1998 - 2012, Daniel Stenberg, <daniel@haxx.se>.

+ * Copyright (C) 1998 - 2008, Daniel Stenberg, <daniel@haxx.se>.

+ * Copyright (C) 1998 - 2010, Daniel Stenberg, <daniel@haxx.se>.

+ * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>.

+

+Curl License

+Copyright (c) 1996 - 2003, Daniel Stenberg, <daniel@haxx.se>.

+

+All rights reserved.

+

+Permission to use, copy, modify, and distribute this software for any purposewith or without fee is hereby granted,

+provided that the above copyright notice and this permission notice appear in all copies.

+

+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE

+WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. IN NO EVENT

+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF

+CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USEOR OTHER DEALINGS IN THE

+SOFTWARE.

+

+Except as contained in this notice, the name of a copyright holder shall not be used in advertising or otherwise to

+promote the sale, use or other dealings in this Software without prior written authorization of the copyright holder.

diff --git a/src/connectivity/gps/gps_hal/README b/src/connectivity/gps/gps_hal/README
new file mode 100644
index 0000000..92f6303
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/README
@@ -0,0 +1,44 @@
+This directory contains GPS HAL layer code.
+
+WHAT IT DOES?
+=============
+It provide GPS interfaces for gps provider on frameworks,which allow init/open/close/cleanup gps 
+when mnld daemon is launched.
+
+HOW IT WAS BUILT?
+==================
+
+It needs the following libs from AOSP:
+1.  libc.so
+2.  libcutils
+3.  libnetutils
+4.  libhardware
+5.  libandroid_runtime
+6.  libnativehelper
+7.  libcrypto
+8.  libssl
+9.  libz
+
+and the following libs from MediaTek:
+1. liblog.so
+2. libepos.a
+3. libcurl
+
+All source/dependency modules of this module are already put in
+'vendor/mediatek/libs' folder.
+
+
+HOW TO USE IT?
+==============
+
+Files in this directory is used to
+generate a library which's name is 'gps.mtxxxx.so'
+
+
+gps.mtxxxx
+mtxxxx means chip platform name,
+The lib 'gps.mtxxxx' is loaded by system_server,
+GPS Location provider will call gps_module_methods API, if system_server is launched.
+
+All the source code of this library were written by MediaTek co..
+
diff --git a/src/connectivity/gps/gps_hal/configure.ac b/src/connectivity/gps/gps_hal/configure.ac
new file mode 100644
index 0000000..9334153
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/configure.ac
@@ -0,0 +1,8 @@
+AC_INIT([gpshal], [1.0])
+AM_INIT_AUTOMAKE([foreign])
+AC_CONFIG_HEADER(defines.h)
+AC_PROG_CC
+AC_DISABLE_STATIC
+LT_INIT
+AC_CONFIG_FILES([Makefile])
+AC_OUTPUT
diff --git a/src/connectivity/gps/gps_hal/hardware/gps.h b/src/connectivity/gps/gps_hal/hardware/gps.h
new file mode 100644
index 0000000..11804f3
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/hardware/gps.h
@@ -0,0 +1,2234 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_INCLUDE_HARDWARE_GPS_H
+#define ANDROID_INCLUDE_HARDWARE_GPS_H
+
+#ifdef __LINUX_OS__
+#include <stdint.h>
+#include <sys/cdefs.h>
+#include <sys/types.h>
+#include <pthread.h>
+#include <sys/socket.h>
+#include <stdbool.h>
+
+__BEGIN_DECLS
+
+/*
+ * Enums defined in HIDL in hardware/interfaces are auto-generated and present
+ * in gnss-base.h.
+ */
+
+/* for compatibility */
+
+/*#define GPS_REQUEST_AGPS_DATA_CONN GNSS_REQUEST_AGNSS_DATA_CONN
+#define GPS_RELEASE_AGPS_DATA_CONN GNSS_RELEASE_AGNSS_DATA_CONN
+#define GPS_AGPS_DATA_CONNECTED GNSS_AGNSS_DATA_CONNECTED
+#define GPS_AGPS_DATA_CONN_DONE GNSS_AGNSS_DATA_CONN_DONE
+#define GPS_AGPS_DATA_CONN_FAILED GNSS_AGNSS_DATA_CONN_FAILED
+#define AGPS_RIL_NETWORK_TYPE_MOBILE_MMS AGPS_RIL_NETWORK_TYPE_MMS
+#define AGPS_RIL_NETWORK_TYPE_MOBILE_SUPL AGPS_RIL_NETWORK_TYPE_SUPL
+#define AGPS_RIL_NETWORK_TTYPE_MOBILE_DUN AGPS_RIL_NETWORK_TYPE_DUN
+#define AGPS_RIL_NETWORK_TTYPE_MOBILE_HIPRI AGPS_RIL_NETWORK_TYPE_HIPRI
+#define AGPS_RIL_NETWORK_TTYPE_WIMAX AGPS_RIL_NETWORK_TYPE_WIMAX
+#define GNSS_MULTIPATH_INDICATOR_NOT_PRESENT GNSS_MULTIPATH_INDICATIOR_NOT_PRESENT
+#define AGPS_SETID_TYPE_MSISDN AGPS_SETID_TYPE_MSISDM
+#define GPS_MEASUREMENT_OPERATION_SUCCESS GPS_MEASUREMENT_SUCCESS
+#define GPS_NAVIGATION_MESSAGE_OPERATION_SUCCESS GPS_NAVIGATION_MESSAGE_SUCCESS
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L1CA GNSS_NAVIGATION_MESSAGE_TYPE_GNSS_L1CA
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L2CNAV GNSS_NAVIGATION_MESSAGE_TYPE_GNSS_L2CNAV
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L5CNAV GNSS_NAVIGATION_MESSAGE_TYPE_GNSS_L5CNAV
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_CNAV2 GNSS_NAVIGATION_MESSAGE_TYPE_GNSS_CNAV2
+#define GPS_LOCATION_HAS_ACCURACY GPS_LOCATION_HAS_HORIZONTAL_ACCURACY
+*/
+/**
+ * The id of this module
+ */
+#define GPS_HARDWARE_MODULE_ID "gps"
+
+#define GPS_NAVIGATION_MESSAGE_OPERATION_SUCCESS             0
+#define GPS_NAVIGATION_MESSAGE_ERROR_ALREADY_INIT         -100
+#define GPS_NAVIGATION_MESSAGE_ERROR_GENERIC              -101
+
+/** Milliseconds since January 1, 1970 */
+typedef int64_t GpsUtcTime;
+
+/** Maximum number of SVs for gps_sv_status_callback(). */
+#define GPS_MAX_SVS 32
+/** Maximum number of SVs for gps_sv_status_callback(). */
+#define GNSS_MAX_SVS 64
+
+/** Maximum number of Measurements in gps_measurement_callback(). */
+#define GPS_MAX_MEASUREMENT   32
+
+/** Maximum number of Measurements in gnss_measurement_callback(). */
+#define GNSS_MAX_MEASUREMENT   64
+
+/** Requested operational mode for GPS operation. */
+typedef uint32_t GpsPositionMode;
+/* IMPORTANT: Note that the following values must match
+ * constants in GpsLocationProvider.java. */
+/** Mode for running GPS standalone (no assistance). */
+#define GPS_POSITION_MODE_STANDALONE    0
+/** AGPS MS-Based mode. */
+#define GPS_POSITION_MODE_MS_BASED      1
+/**
+ * AGPS MS-Assisted mode. This mode is not maintained by the platform anymore.
+ * It is strongly recommended to use GPS_POSITION_MODE_MS_BASED instead.
+ */
+#define GPS_POSITION_MODE_MS_ASSISTED   2
+
+/** Requested recurrence mode for GPS operation. */
+typedef uint32_t GpsPositionRecurrence;
+/* IMPORTANT: Note that the following values must match
+ * constants in GpsLocationProvider.java. */
+/** Receive GPS fixes on a recurring basis at a specified period. */
+#define GPS_POSITION_RECURRENCE_PERIODIC    0
+/** Request a single shot GPS fix. */
+#define GPS_POSITION_RECURRENCE_SINGLE      1
+
+/** GPS status event values. */
+typedef uint16_t GpsStatusValue;
+/* IMPORTANT: Note that the following values must match
+ * constants in GpsLocationProvider.java. */
+/** GPS status unknown. */
+#define GPS_STATUS_NONE             0
+/** GPS has begun navigating. */
+#define GPS_STATUS_SESSION_BEGIN    1
+/** GPS has stopped navigating. */
+#define GPS_STATUS_SESSION_END      2
+/** GPS has powered on but is not navigating. */
+#define GPS_STATUS_ENGINE_ON        3
+/** GPS is powered off. */
+#define GPS_STATUS_ENGINE_OFF       4
+
+/** Flags to indicate which values are valid in a GpsLocation. */
+typedef uint16_t GpsLocationFlags;
+/* IMPORTANT: Note that the following values must match
+ * constants in GpsLocationProvider.java. */
+/** GpsLocation has valid latitude and longitude. */
+#define GPS_LOCATION_HAS_LAT_LONG   0x0001
+/** GpsLocation has valid altitude. */
+#define GPS_LOCATION_HAS_ALTITUDE   0x0002
+/** GpsLocation has valid speed. */
+#define GPS_LOCATION_HAS_SPEED      0x0004
+/** GpsLocation has valid bearing. */
+#define GPS_LOCATION_HAS_BEARING    0x0008
+/** GpsLocation has valid accuracy. */
+#define GPS_LOCATION_HAS_ACCURACY   0x0010
+
+/**
+ * GPS HAL schedules fixes for GPS_POSITION_RECURRENCE_PERIODIC mode. If this is
+ * not set, then the framework will use 1000ms for min_interval and will start
+ * and call start() and stop() to schedule the GPS.
+ */
+#define GPS_CAPABILITY_SCHEDULING       (1 << 0)
+/** GPS supports MS-Based AGPS mode */
+#define GPS_CAPABILITY_MSB              (1 << 1)
+/** GPS supports MS-Assisted AGPS mode */
+#define GPS_CAPABILITY_MSA              (1 << 2)
+/** GPS supports single-shot fixes */
+#define GPS_CAPABILITY_SINGLE_SHOT      (1 << 3)
+/** GPS supports on demand time injection */
+#define GPS_CAPABILITY_ON_DEMAND_TIME   (1 << 4)
+/** GPS supports Geofencing  */
+#define GPS_CAPABILITY_GEOFENCING       (1 << 5)
+/** GPS supports Measurements. */
+#define GPS_CAPABILITY_MEASUREMENTS     (1 << 6)
+/** GPS supports Navigation Messages */
+#define GPS_CAPABILITY_NAV_MESSAGES     (1 << 7)
+
+/**
+ * Flags used to specify which aiding data to delete when calling
+ * delete_aiding_data().
+ */
+typedef uint16_t GpsAidingData;
+/* IMPORTANT: Note that the following values must match
+ * constants in GpsLocationProvider.java. */
+#define GPS_DELETE_EPHEMERIS        0x0001
+#define GPS_DELETE_ALMANAC          0x0002
+#define GPS_DELETE_POSITION         0x0004
+#define GPS_DELETE_TIME             0x0008
+#define GPS_DELETE_IONO             0x0010
+#define GPS_DELETE_UTC              0x0020
+#define GPS_DELETE_HEALTH           0x0040
+#define GPS_DELETE_SVDIR            0x0080
+#define GPS_DELETE_SVSTEER          0x0100
+#define GPS_DELETE_SADATA           0x0200
+#define GPS_DELETE_RTI              0x0400
+#define GPS_DELETE_CELLDB_INFO      0x8000
+#define GPS_DELETE_ALL              0xFFFF
+
+/** AGPS type */
+typedef uint16_t AGpsType;
+#define AGPS_TYPE_SUPL          1
+#define AGPS_TYPE_C2K           2
+
+typedef uint16_t AGpsSetIDType;
+#define AGPS_SETID_TYPE_NONE    0
+#define AGPS_SETID_TYPE_IMSI    1
+#define AGPS_SETID_TYPE_MSISDN  2
+
+typedef uint16_t ApnIpType;
+#define APN_IP_INVALID          0
+#define APN_IP_IPV4             1
+#define APN_IP_IPV6             2
+#define APN_IP_IPV4V6           3
+
+/**
+ * String length constants
+ */
+#define GPS_NI_SHORT_STRING_MAXLEN      256
+#define GPS_NI_LONG_STRING_MAXLEN       2048
+
+/**
+ * GpsNiType constants
+ */
+typedef uint32_t GpsNiType;
+#define GPS_NI_TYPE_VOICE              1
+#define GPS_NI_TYPE_UMTS_SUPL          2
+#define GPS_NI_TYPE_UMTS_CTRL_PLANE    3
+
+/**
+ * GpsNiNotifyFlags constants
+ */
+typedef uint32_t GpsNiNotifyFlags;
+/** NI requires notification */
+#define GPS_NI_NEED_NOTIFY          0x0001
+/** NI requires verification */
+#define GPS_NI_NEED_VERIFY          0x0002
+/** NI requires privacy override, no notification/minimal trace */
+#define GPS_NI_PRIVACY_OVERRIDE     0x0004
+
+/**
+ * GPS NI responses, used to define the response in
+ * NI structures
+ */
+typedef int GpsUserResponseType;
+#define GPS_NI_RESPONSE_ACCEPT         1
+#define GPS_NI_RESPONSE_DENY           2
+#define GPS_NI_RESPONSE_NORESP         3
+
+/**
+ * NI data encoding scheme
+ */
+typedef int GpsNiEncodingType;
+#define GPS_ENC_NONE                   0
+#define GPS_ENC_SUPL_GSM_DEFAULT       1
+#define GPS_ENC_SUPL_UTF8              2
+#define GPS_ENC_SUPL_UCS2              3
+#define GPS_ENC_UNKNOWN                -1
+
+/** AGPS status event values. */
+typedef uint16_t AGpsStatusValue;
+/** GPS requests data connection for AGPS. */
+#define GPS_REQUEST_AGPS_DATA_CONN  1
+/** GPS releases the AGPS data connection. */
+#define GPS_RELEASE_AGPS_DATA_CONN  2
+/** AGPS data connection initiated */
+#define GPS_AGPS_DATA_CONNECTED     3
+/** AGPS data connection completed */
+#define GPS_AGPS_DATA_CONN_DONE     4
+/** AGPS data connection failed */
+#define GPS_AGPS_DATA_CONN_FAILED   5
+
+typedef uint16_t AGpsRefLocationType;
+#define AGPS_REF_LOCATION_TYPE_GSM_CELLID   1
+#define AGPS_REF_LOCATION_TYPE_UMTS_CELLID  2
+#define AGPS_REF_LOCATION_TYPE_MAC          3
+#define AGPS_REF_LOCATION_TYPE_LTE_CELLID   4
+
+/* Deprecated, to be removed in the next Android release. */
+#define AGPS_REG_LOCATION_TYPE_MAC          3
+
+/** Network types for update_network_state "type" parameter */
+#define AGPS_RIL_NETWORK_TYPE_MOBILE        0
+#define AGPS_RIL_NETWORK_TYPE_WIFI          1
+#define AGPS_RIL_NETWORK_TYPE_MOBILE_MMS    2
+#define AGPS_RIL_NETWORK_TYPE_MOBILE_SUPL   3
+#define AGPS_RIL_NETWORK_TTYPE_MOBILE_DUN   4
+#define AGPS_RIL_NETWORK_TTYPE_MOBILE_HIPRI 5
+#define AGPS_RIL_NETWORK_TTYPE_WIMAX        6
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. */
+typedef uint16_t GpsClockFlags;
+#define GPS_CLOCK_HAS_LEAP_SECOND               (1<<0)
+#define GPS_CLOCK_HAS_TIME_UNCERTAINTY          (1<<1)
+#define GPS_CLOCK_HAS_FULL_BIAS                 (1<<2)
+#define GPS_CLOCK_HAS_BIAS                      (1<<3)
+#define GPS_CLOCK_HAS_BIAS_UNCERTAINTY          (1<<4)
+#define GPS_CLOCK_HAS_DRIFT                     (1<<5)
+#define GPS_CLOCK_HAS_DRIFT_UNCERTAINTY         (1<<6)
+
+/**
+ * Flags to indicate what fields in GnssClock are valid.
+ */
+typedef uint16_t GnssClockFlags;
+/** A valid 'leap second' is stored in the data structure. */
+#define GNSS_CLOCK_HAS_LEAP_SECOND               (1<<0)
+/** A valid 'time uncertainty' is stored in the data structure. */
+#define GNSS_CLOCK_HAS_TIME_UNCERTAINTY          (1<<1)
+/** A valid 'full bias' is stored in the data structure. */
+#define GNSS_CLOCK_HAS_FULL_BIAS                 (1<<2)
+/** A valid 'bias' is stored in the data structure. */
+#define GNSS_CLOCK_HAS_BIAS                      (1<<3)
+/** A valid 'bias uncertainty' is stored in the data structure. */
+#define GNSS_CLOCK_HAS_BIAS_UNCERTAINTY          (1<<4)
+/** A valid 'drift' is stored in the data structure. */
+#define GNSS_CLOCK_HAS_DRIFT                     (1<<5)
+/** A valid 'drift uncertainty' is stored in the data structure. */
+#define GNSS_CLOCK_HAS_DRIFT_UNCERTAINTY         (1<<6)
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. */
+typedef uint8_t GpsClockType;
+#define GPS_CLOCK_TYPE_UNKNOWN                  0
+#define GPS_CLOCK_TYPE_LOCAL_HW_TIME            1
+#define GPS_CLOCK_TYPE_GPS_TIME                 2
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. */
+typedef uint32_t GpsMeasurementFlags;
+#define GPS_MEASUREMENT_HAS_SNR                               (1<<0)
+#define GPS_MEASUREMENT_HAS_ELEVATION                         (1<<1)
+#define GPS_MEASUREMENT_HAS_ELEVATION_UNCERTAINTY             (1<<2)
+#define GPS_MEASUREMENT_HAS_AZIMUTH                           (1<<3)
+#define GPS_MEASUREMENT_HAS_AZIMUTH_UNCERTAINTY               (1<<4)
+#define GPS_MEASUREMENT_HAS_PSEUDORANGE                       (1<<5)
+#define GPS_MEASUREMENT_HAS_PSEUDORANGE_UNCERTAINTY           (1<<6)
+#define GPS_MEASUREMENT_HAS_CODE_PHASE                        (1<<7)
+#define GPS_MEASUREMENT_HAS_CODE_PHASE_UNCERTAINTY            (1<<8)
+#define GPS_MEASUREMENT_HAS_CARRIER_FREQUENCY                 (1<<9)
+#define GPS_MEASUREMENT_HAS_CARRIER_CYCLES                    (1<<10)
+#define GPS_MEASUREMENT_HAS_CARRIER_PHASE                     (1<<11)
+#define GPS_MEASUREMENT_HAS_CARRIER_PHASE_UNCERTAINTY         (1<<12)
+#define GPS_MEASUREMENT_HAS_BIT_NUMBER                        (1<<13)
+#define GPS_MEASUREMENT_HAS_TIME_FROM_LAST_BIT                (1<<14)
+#define GPS_MEASUREMENT_HAS_DOPPLER_SHIFT                     (1<<15)
+#define GPS_MEASUREMENT_HAS_DOPPLER_SHIFT_UNCERTAINTY         (1<<16)
+#define GPS_MEASUREMENT_HAS_USED_IN_FIX                       (1<<17)
+#define GPS_MEASUREMENT_HAS_UNCORRECTED_PSEUDORANGE_RATE      (1<<18)
+
+/**
+ * Flags to indicate what fields in GnssMeasurement are valid.
+ */
+typedef uint32_t GnssMeasurementFlags;
+/** A valid 'snr' is stored in the data structure. */
+#define GNSS_MEASUREMENT_HAS_SNR                               (1<<0)
+/** A valid 'carrier frequency' is stored in the data structure. */
+#define GNSS_MEASUREMENT_HAS_CARRIER_FREQUENCY                 (1<<9)
+/** A valid 'carrier cycles' is stored in the data structure. */
+#define GNSS_MEASUREMENT_HAS_CARRIER_CYCLES                    (1<<10)
+/** A valid 'carrier phase' is stored in the data structure. */
+#define GNSS_MEASUREMENT_HAS_CARRIER_PHASE                     (1<<11)
+/** A valid 'carrier phase uncertainty' is stored in the data structure. */
+#define GNSS_MEASUREMENT_HAS_CARRIER_PHASE_UNCERTAINTY         (1<<12)
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. */
+typedef uint8_t GpsLossOfLock;
+#define GPS_LOSS_OF_LOCK_UNKNOWN                            0
+#define GPS_LOSS_OF_LOCK_OK                                 1
+#define GPS_LOSS_OF_LOCK_CYCLE_SLIP                         2
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. Use GnssMultipathIndicator instead.
+ */
+typedef uint8_t GpsMultipathIndicator;
+#define GPS_MULTIPATH_INDICATOR_UNKNOWN                 0
+#define GPS_MULTIPATH_INDICATOR_DETECTED                1
+#define GPS_MULTIPATH_INDICATOR_NOT_USED                2
+
+/**
+ * Enumeration of available values for the GNSS Measurement's multipath
+ * indicator.
+ */
+typedef uint8_t GnssMultipathIndicator;
+/** The indicator is not available or unknown. */
+#define GNSS_MULTIPATH_INDICATOR_UNKNOWN                 0
+/** The measurement is indicated to be affected by multipath. */
+#define GNSS_MULTIPATH_INDICATOR_PRESENT                 1
+/** The measurement is indicated to be not affected by multipath. */
+#define GNSS_MULTIPATH_INDICATOR_NOT_PRESENT             2
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. */
+typedef uint16_t GpsMeasurementState;
+#define GPS_MEASUREMENT_STATE_UNKNOWN                   0
+#define GPS_MEASUREMENT_STATE_CODE_LOCK             (1<<0)
+#define GPS_MEASUREMENT_STATE_BIT_SYNC              (1<<1)
+#define GPS_MEASUREMENT_STATE_SUBFRAME_SYNC         (1<<2)
+#define GPS_MEASUREMENT_STATE_TOW_DECODED           (1<<3)
+#define GPS_MEASUREMENT_STATE_MSEC_AMBIGUOUS        (1<<4)
+
+/**
+ * Flags indicating the GNSS measurement state.
+ *
+ * The expected behavior here is for GPS HAL to set all the flags that applies.
+ * For example, if the state for a satellite is only C/A code locked and bit
+ * synchronized, and there is still millisecond ambiguity, the state should be
+ * set as:
+ *
+ * GNSS_MEASUREMENT_STATE_CODE_LOCK | GNSS_MEASUREMENT_STATE_BIT_SYNC |
+ *         GNSS_MEASUREMENT_STATE_MSEC_AMBIGUOUS
+ *
+ * If GNSS is still searching for a satellite, the corresponding state should be
+ * set to GNSS_MEASUREMENT_STATE_UNKNOWN(0).
+ */
+typedef uint32_t GnssMeasurementState;
+#define GNSS_MEASUREMENT_STATE_UNKNOWN                   0
+#define GNSS_MEASUREMENT_STATE_CODE_LOCK             (1<<0)
+#define GNSS_MEASUREMENT_STATE_BIT_SYNC              (1<<1)
+#define GNSS_MEASUREMENT_STATE_SUBFRAME_SYNC         (1<<2)
+#define GNSS_MEASUREMENT_STATE_TOW_DECODED           (1<<3)
+#define GNSS_MEASUREMENT_STATE_MSEC_AMBIGUOUS        (1<<4)
+#define GNSS_MEASUREMENT_STATE_SYMBOL_SYNC           (1<<5)
+#define GNSS_MEASUREMENT_STATE_GLO_STRING_SYNC       (1<<6)
+#define GNSS_MEASUREMENT_STATE_GLO_TOD_DECODED       (1<<7)
+#define GNSS_MEASUREMENT_STATE_BDS_D2_BIT_SYNC       (1<<8)
+#define GNSS_MEASUREMENT_STATE_BDS_D2_SUBFRAME_SYNC  (1<<9)
+#define GNSS_MEASUREMENT_STATE_GAL_E1BC_CODE_LOCK    (1<<10)
+#define GNSS_MEASUREMENT_STATE_GAL_E1C_2ND_CODE_LOCK (1<<11)
+#define GNSS_MEASUREMENT_STATE_GAL_E1B_PAGE_SYNC     (1<<12)
+#define GNSS_MEASUREMENT_STATE_SBAS_SYNC             (1<<13)
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. */
+typedef uint16_t GpsAccumulatedDeltaRangeState;
+#define GPS_ADR_STATE_UNKNOWN                       0
+#define GPS_ADR_STATE_VALID                     (1<<0)
+#define GPS_ADR_STATE_RESET                     (1<<1)
+#define GPS_ADR_STATE_CYCLE_SLIP                (1<<2)
+
+/**
+ * Flags indicating the Accumulated Delta Range's states.
+ */
+typedef uint16_t GnssAccumulatedDeltaRangeState;
+#define GNSS_ADR_STATE_UNKNOWN                       0
+#define GNSS_ADR_STATE_VALID                     (1<<0)
+#define GNSS_ADR_STATE_RESET                     (1<<1)
+#define GNSS_ADR_STATE_CYCLE_SLIP                (1<<2)
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. */
+typedef uint8_t GpsNavigationMessageType;
+#define GPS_NAVIGATION_MESSAGE_TYPE_UNKNOWN         0
+#define GPS_NAVIGATION_MESSAGE_TYPE_L1CA            1
+#define GPS_NAVIGATION_MESSAGE_TYPE_L2CNAV          2
+#define GPS_NAVIGATION_MESSAGE_TYPE_L5CNAV          3
+#define GPS_NAVIGATION_MESSAGE_TYPE_CNAV2           4
+
+/**
+ * Enumeration of available values to indicate the GNSS Navigation message
+ * types.
+ *
+ * For convenience, first byte is the GnssConstellationType on which that signal
+ * is typically transmitted
+ */
+typedef int16_t GnssNavigationMessageType;
+
+#define GNSS_NAVIGATION_MESSAGE_TYPE_UNKNOWN       0
+/** GPS L1 C/A message contained in the structure.  */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L1CA      0x0101
+/** GPS L2-CNAV message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L2CNAV    0x0102
+/** GPS L5-CNAV message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L5CNAV    0x0103
+/** GPS CNAV-2 message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_CNAV2     0x0104
+/** Glonass L1 CA message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GLO_L1CA      0x0301
+/** Beidou D1 message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_BDS_D1        0x0501
+/** Beidou D2 message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_BDS_D2        0x0502
+/** Galileo I/NAV message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GAL_I         0x0601
+/** Galileo F/NAV message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GAL_F         0x0602
+
+/**
+ * Status of Navigation Message
+ * When a message is received properly without any parity error in its navigation words, the
+ * status should be set to NAV_MESSAGE_STATUS_PARITY_PASSED. But if a message is received
+ * with words that failed parity check, but GPS is able to correct those words, the status
+ * should be set to NAV_MESSAGE_STATUS_PARITY_REBUILT.
+ * No need to send any navigation message that contains words with parity error and cannot be
+ * corrected.
+ */
+typedef uint16_t NavigationMessageStatus;
+#define NAV_MESSAGE_STATUS_UNKNOWN              0
+#define NAV_MESSAGE_STATUS_PARITY_PASSED   (1<<0)
+#define NAV_MESSAGE_STATUS_PARITY_REBUILT  (1<<1)
+
+/* This constant is deprecated, and will be removed in the next release. */
+#define NAV_MESSAGE_STATUS_UNKONW              0
+
+/**
+ * Flags that indicate information about the satellite
+ */
+typedef uint8_t                                 GnssSvFlags;
+#define GNSS_SV_FLAGS_NONE                      0
+#define GNSS_SV_FLAGS_HAS_EPHEMERIS_DATA        (1 << 0)
+#define GNSS_SV_FLAGS_HAS_ALMANAC_DATA          (1 << 1)
+#define GNSS_SV_FLAGS_USED_IN_FIX               (1 << 2)
+
+/**
+ * Constellation type of GnssSvInfo
+ */
+typedef uint8_t                         GnssConstellationType;
+#define GNSS_CONSTELLATION_UNKNOWN      0
+#define GNSS_CONSTELLATION_GPS          1
+#define GNSS_CONSTELLATION_SBAS         2
+#define GNSS_CONSTELLATION_GLONASS      3
+#define GNSS_CONSTELLATION_QZSS         4
+#define GNSS_CONSTELLATION_BEIDOU       5
+#define GNSS_CONSTELLATION_GALILEO      6
+
+/**
+ * Name for the GPS XTRA interface.
+ */
+#define GPS_XTRA_INTERFACE      "gps-xtra"
+
+/**
+ * Name for the GPS DEBUG interface.
+ */
+#define GPS_DEBUG_INTERFACE      "gps-debug"
+
+/**
+ * Name for the AGPS interface.
+ */
+#define AGPS_INTERFACE      "agps"
+
+/**
+ * Name of the Supl Certificate interface.
+ */
+#define SUPL_CERTIFICATE_INTERFACE  "supl-certificate"
+
+/**
+ * Name for NI interface
+ */
+#define GPS_NI_INTERFACE "gps-ni"
+
+/**
+ * Name for the AGPS-RIL interface.
+ */
+#define AGPS_RIL_INTERFACE      "agps_ril"
+
+/**
+ * Name for the GPS_Geofencing interface.
+ */
+#define GPS_GEOFENCING_INTERFACE   "gps_geofencing"
+
+/**
+ * Name of the GPS Measurements interface.
+ */
+#define GPS_MEASUREMENT_INTERFACE   "gps_measurement"
+
+/**
+ * Name of the GPS navigation message interface.
+ */
+#define GPS_NAVIGATION_MESSAGE_INTERFACE     "gps_navigation_message"
+
+/**
+ * Name of the GNSS/GPS configuration interface.
+ */
+#define GNSS_CONFIGURATION_INTERFACE     "gnss_configuration"
+
+/** Represents a location. */
+typedef struct {
+    /** set to sizeof(GpsLocation) */
+    size_t          size;
+    /** Contains GpsLocationFlags bits. */
+    uint16_t        flags;
+    /** Represents latitude in degrees. */
+    double          latitude;
+    /** Represents longitude in degrees. */
+    double          longitude;
+    /**
+     * Represents altitude in meters above the WGS 84 reference ellipsoid.
+     */
+    double          altitude;
+    /** Represents speed in meters per second. */
+    float           speed;
+    /** Represents heading in degrees. */
+    float           bearing;
+    /** Represents expected accuracy in meters. */
+    float           accuracy;
+    /** Timestamp for the location fix. */
+    GpsUtcTime      timestamp;
+} GpsLocation;
+
+/** Represents the status. */
+typedef struct {
+    /** set to sizeof(GpsStatus) */
+    size_t          size;
+    GpsStatusValue status;
+} GpsStatus;
+
+/**
+ * Legacy struct to represents SV information.
+ * Deprecated, to be removed in the next Android release.
+ * Use GnssSvInfo instead.
+ */
+typedef struct {
+    /** set to sizeof(GpsSvInfo) */
+    size_t          size;
+    /** Pseudo-random number for the SV. */
+    int     prn;
+    /** Signal to noise ratio. */
+    float   snr;
+    /** Elevation of SV in degrees. */
+    float   elevation;
+    /** Azimuth of SV in degrees. */
+    float   azimuth;
+} GpsSvInfo;
+
+typedef struct {
+    /** set to sizeof(GnssSvInfo) */
+    size_t size;
+
+    /**
+     * Pseudo-random number for the SV, or FCN/OSN number for Glonass. The
+     * distinction is made by looking at constellation field. Values should be
+     * in the range of:
+     *
+     * - GPS:     1-32
+     * - SBAS:    120-151, 183-192
+     * - GLONASS: 1-24, the orbital slot number (OSN), if known.  Or, if not:
+     *            93-106, the frequency channel number (FCN) (-7 to +6) offset by + 100
+     *            i.e. report an FCN of -7 as 93, FCN of 0 as 100, and FCN of +6 as 106.
+     * - QZSS:    193-200
+     * - Galileo: 1-36
+     * - Beidou:  1-37
+     */
+    int16_t svid;
+
+    /**
+     * Defines the constellation of the given SV. Value should be one of those
+     * GNSS_CONSTELLATION_* constants
+     */
+    GnssConstellationType constellation;
+
+    /**
+     * Carrier-to-noise density in dB-Hz, typically in the range [0, 63].
+     * It contains the measured C/N0 value for the signal at the antenna port.
+     *
+     * This is a mandatory value.
+     */
+    float c_n0_dbhz;
+
+    /** Elevation of SV in degrees. */
+    float elevation;
+
+    /** Azimuth of SV in degrees. */
+    float azimuth;
+
+    /**
+     * Contains additional data about the given SV. Value should be one of those
+     * GNSS_SV_FLAGS_* constants
+     */
+    GnssSvFlags flags;
+
+} GnssSvInfo;
+
+/**
+ * Legacy struct to represents SV status.
+ * Deprecated, to be removed in the next Android release.
+ * Use GnssSvStatus instead.
+ */
+typedef struct {
+    /** set to sizeof(GpsSvStatus) */
+    size_t size;
+    int num_svs;
+    GpsSvInfo sv_list[GPS_MAX_SVS];
+    uint32_t ephemeris_mask;
+    uint32_t almanac_mask;
+    uint32_t used_in_fix_mask;
+} GpsSvStatus;
+
+/**
+ * Represents SV status.
+ */
+typedef struct {
+    /** set to sizeof(GnssSvStatus) */
+    size_t size;
+
+    /** Number of GPS SVs currently visible, refers to the SVs stored in sv_list */
+    int num_svs;
+    /**
+     * Pointer to an array of SVs information for all GNSS constellations,
+     * except GPS, which is reported using sv_list
+     */
+    GnssSvInfo gnss_sv_list[GNSS_MAX_SVS];
+
+} GnssSvStatus;
+
+/* CellID for 2G, 3G and LTE, used in AGPS. */
+typedef struct {
+    AGpsRefLocationType type;
+    /** Mobile Country Code. */
+    uint16_t mcc;
+    /** Mobile Network Code .*/
+    uint16_t mnc;
+    /** Location Area Code in 2G, 3G and LTE. In 3G lac is discarded. In LTE,
+     * lac is populated with tac, to ensure that we don't break old clients that
+     * might rely in the old (wrong) behavior.
+     */
+    uint16_t lac;
+    /** Cell id in 2G. Utran Cell id in 3G. Cell Global Id EUTRA in LTE. */
+    uint32_t cid;
+    /** Tracking Area Code in LTE. */
+    uint16_t tac;
+    /** Physical Cell id in LTE (not used in 2G and 3G) */
+    uint16_t pcid;
+} AGpsRefLocationCellID;
+
+typedef struct {
+    uint8_t mac[6];
+} AGpsRefLocationMac;
+
+/** Represents ref locations */
+typedef struct {
+    AGpsRefLocationType type;
+    union {
+        AGpsRefLocationCellID   cellID;
+        AGpsRefLocationMac      mac;
+    } u;
+} AGpsRefLocation;
+
+/**
+ * Callback with location information. Can only be called from a thread created
+ * by create_thread_cb.
+ */
+typedef void (* gps_location_callback)(GpsLocation* location);
+
+/**
+ * Callback with status information. Can only be called from a thread created by
+ * create_thread_cb.
+ */
+typedef void (* gps_status_callback)(GpsStatus* status);
+
+/**
+ * Legacy callback with SV status information.
+ * Can only be called from a thread created by create_thread_cb.
+ *
+ * This callback is deprecated, and will be removed in the next release. Use
+ * gnss_sv_status_callback() instead.
+ */
+typedef void (* gps_sv_status_callback)(GpsSvStatus* sv_info);
+
+/**
+ * Callback with SV status information.
+ * Can only be called from a thread created by create_thread_cb.
+ */
+typedef void (* gnss_sv_status_callback)(GnssSvStatus* sv_info);
+
+/**
+ * Callback for reporting NMEA sentences. Can only be called from a thread
+ * created by create_thread_cb.
+ */
+typedef void (* gps_nmea_callback)(GpsUtcTime timestamp, const char* nmea, int length);
+
+/**
+ * Callback to inform framework of the GPS engine's capabilities. Capability
+ * parameter is a bit field of GPS_CAPABILITY_* flags.
+ */
+typedef void (* gps_set_capabilities)(uint32_t capabilities);
+
+/**
+ * Callback utility for acquiring the GPS wakelock. This can be used to prevent
+ * the CPU from suspending while handling GPS events.
+ */
+typedef void (* gps_acquire_wakelock)();
+
+/** Callback utility for releasing the GPS wakelock. */
+typedef void (* gps_release_wakelock)();
+
+/** Callback for requesting NTP time */
+typedef void (* gps_request_utc_time)();
+
+/**
+ * Callback for creating a thread that can call into the Java framework code.
+ * This must be used to create any threads that report events up to the
+ * framework.
+ */
+typedef pthread_t (* gps_create_thread)(const char* name, void (*start)(void *), void* arg);
+
+/**
+ * Provides information about how new the underlying GPS/GNSS hardware and
+ * software is.
+ *
+ * This information will be available for Android Test Applications. If a GPS
+ * HAL does not provide this information, it will be considered "2015 or
+ * earlier".
+ *
+ * If a GPS HAL does provide this information, then newer years will need to
+ * meet newer CTS standards. E.g. if the date are 2016 or above, then N+ level
+ * GpsMeasurement support will be verified.
+ */
+typedef struct {
+    /** Set to sizeof(GnssSystemInfo) */
+    size_t   size;
+    /* year in which the last update was made to the underlying hardware/firmware
+     * used to capture GNSS signals, e.g. 2016 */
+    uint16_t year_of_hw;
+} GnssSystemInfo;
+
+/**
+ * Callback to inform framework of the engine's hardware version information.
+ */
+typedef void (*gnss_set_system_info)(const GnssSystemInfo* info);
+
+/** New GPS callback structure. */
+typedef struct {
+    /** set to sizeof(GpsCallbacks) */
+    size_t      size;
+    gps_location_callback location_cb;
+    gps_status_callback status_cb;
+    gps_sv_status_callback sv_status_cb;
+    gps_nmea_callback nmea_cb;
+    gps_set_capabilities set_capabilities_cb;
+    gps_acquire_wakelock acquire_wakelock_cb;
+    gps_release_wakelock release_wakelock_cb;
+    gps_create_thread create_thread_cb;
+    gps_request_utc_time request_utc_time_cb;
+
+    gnss_set_system_info set_system_info_cb;
+    gnss_sv_status_callback gnss_sv_status_cb;
+} GpsCallbacks;
+
+/** Represents the standard GPS interface. */
+typedef struct {
+    /** set to sizeof(GpsInterface) */
+    size_t          size;
+    /**
+     * Opens the interface and provides the callback routines
+     * to the implementation of this interface.
+     */
+    int   (*init)( GpsCallbacks* callbacks );
+
+    /** Starts navigating. */
+    int   (*start)( void );
+
+    /** Stops navigating. */
+    int   (*stop)( void );
+
+    /** Closes the interface. */
+    void  (*cleanup)( void );
+
+    /** Injects the current time. */
+    int   (*inject_time)(GpsUtcTime time, int64_t timeReference,
+                         int uncertainty);
+
+    /**
+     * Injects current location from another location provider (typically cell
+     * ID). Latitude and longitude are measured in degrees expected accuracy is
+     * measured in meters
+     */
+    int  (*inject_location)(double latitude, double longitude, float accuracy);
+
+    /**
+     * Specifies that the next call to start will not use the
+     * information defined in the flags. GPS_DELETE_ALL is passed for
+     * a cold start.
+     */
+    void  (*delete_aiding_data)(GpsAidingData flags);
+
+    /**
+     * min_interval represents the time between fixes in milliseconds.
+     * preferred_accuracy represents the requested fix accuracy in meters.
+     * preferred_time represents the requested time to first fix in milliseconds.
+     *
+     * 'mode' parameter should be one of GPS_POSITION_MODE_MS_BASED
+     * or GPS_POSITION_MODE_STANDALONE.
+     * It is allowed by the platform (and it is recommended) to fallback to
+     * GPS_POSITION_MODE_MS_BASED if GPS_POSITION_MODE_MS_ASSISTED is passed in, and
+     * GPS_POSITION_MODE_MS_BASED is supported.
+     */
+    int   (*set_position_mode)(GpsPositionMode mode, GpsPositionRecurrence recurrence,
+            uint32_t min_interval, uint32_t preferred_accuracy, uint32_t preferred_time);
+
+    /** Get a pointer to extension information. */
+    const void* (*get_extension)(const char* name);
+} GpsInterface;
+
+/**
+ * Callback to request the client to download XTRA data. The client should
+ * download XTRA data and inject it by calling inject_xtra_data(). Can only be
+ * called from a thread created by create_thread_cb.
+ */
+typedef void (* gps_xtra_download_request)();
+
+/** Callback structure for the XTRA interface. */
+typedef struct {
+    gps_xtra_download_request download_request_cb;
+    gps_create_thread create_thread_cb;
+} GpsXtraCallbacks;
+
+/** Extended interface for XTRA support. */
+typedef struct {
+    /** set to sizeof(GpsXtraInterface) */
+    size_t          size;
+    /**
+     * Opens the XTRA interface and provides the callback routines
+     * to the implementation of this interface.
+     */
+    int  (*init)( GpsXtraCallbacks* callbacks );
+    /** Injects XTRA data into the GPS. */
+    int  (*inject_xtra_data)( char* data, int length );
+} GpsXtraInterface;
+
+/** Extended interface for DEBUG support. */
+typedef struct {
+    /** set to sizeof(GpsDebugInterface) */
+    size_t          size;
+
+    /**
+     * This function should return any information that the native
+     * implementation wishes to include in a bugreport.
+     */
+    size_t (*get_internal_state)(char* buffer, size_t bufferSize);
+} GpsDebugInterface;
+
+/*
+ * Represents the status of AGPS augmented to support IPv4 and IPv6.
+ */
+typedef struct {
+    /** set to sizeof(AGpsStatus) */
+    size_t                  size;
+
+    AGpsType                type;
+    AGpsStatusValue         status;
+
+    /**
+     * Must be set to a valid IPv4 address if the field 'addr' contains an IPv4
+     * address, or set to INADDR_NONE otherwise.
+     */
+    uint32_t                ipaddr;
+
+    /**
+     * Must contain the IPv4 (AF_INET) or IPv6 (AF_INET6) address to report.
+     * Any other value of addr.ss_family will be rejected.
+     */
+    struct sockaddr_storage addr;
+} AGpsStatus;
+
+/**
+ * Callback with AGPS status information. Can only be called from a thread
+ * created by create_thread_cb.
+ */
+typedef void (* agps_status_callback)(AGpsStatus* status);
+
+/** Callback structure for the AGPS interface. */
+typedef struct {
+    agps_status_callback status_cb;
+    gps_create_thread create_thread_cb;
+} AGpsCallbacks;
+
+/**
+ * Extended interface for AGPS support, it is augmented to enable to pass
+ * extra APN data.
+ */
+typedef struct {
+    /** set to sizeof(AGpsInterface) */
+    size_t size;
+
+    /**
+     * Opens the AGPS interface and provides the callback routines to the
+     * implementation of this interface.
+     */
+    void (*init)(AGpsCallbacks* callbacks);
+    /**
+     * Deprecated.
+     * If the HAL supports AGpsInterface_v2 this API will not be used, see
+     * data_conn_open_with_apn_ip_type for more information.
+     */
+    int (*data_conn_open)(const char* apn);
+    /**
+     * Notifies that the AGPS data connection has been closed.
+     */
+    int (*data_conn_closed)();
+    /**
+     * Notifies that a data connection is not available for AGPS.
+     */
+    int (*data_conn_failed)();
+    /**
+     * Sets the hostname and port for the AGPS server.
+     */
+    int (*set_server)(AGpsType type, const char* hostname, int port);
+
+    /**
+     * Notifies that a data connection is available and sets the name of the
+     * APN, and its IP type, to be used for SUPL connections.
+     */
+    int (*data_conn_open_with_apn_ip_type)(
+            const char* apn,
+            ApnIpType apnIpType);
+} AGpsInterface;
+
+/** Error codes associated with certificate operations */
+#define AGPS_CERTIFICATE_OPERATION_SUCCESS               0
+#define AGPS_CERTIFICATE_ERROR_GENERIC                -100
+#define AGPS_CERTIFICATE_ERROR_TOO_MANY_CERTIFICATES  -101
+
+/** A data structure that represents an X.509 certificate using DER encoding */
+typedef struct {
+    size_t  length;
+    u_char* data;
+} DerEncodedCertificate;
+
+/**
+ * A type definition for SHA1 Fingerprints used to identify X.509 Certificates
+ * The Fingerprint is a digest of the DER Certificate that uniquely identifies it.
+ */
+typedef struct {
+    u_char data[20];
+} Sha1CertificateFingerprint;
+
+/** AGPS Interface to handle SUPL certificate operations */
+typedef struct {
+    /** set to sizeof(SuplCertificateInterface) */
+    size_t size;
+
+    /**
+     * Installs a set of Certificates used for SUPL connections to the AGPS server.
+     * If needed the HAL should find out internally any certificates that need to be removed to
+     * accommodate the certificates to install.
+     * The certificates installed represent a full set of valid certificates needed to connect to
+     * AGPS SUPL servers.
+     * The list of certificates is required, and all must be available at the same time, when trying
+     * to establish a connection with the AGPS Server.
+     *
+     * Parameters:
+     *      certificates - A pointer to an array of DER encoded certificates that are need to be
+     *                     installed in the HAL.
+     *      length - The number of certificates to install.
+     * Returns:
+     *      AGPS_CERTIFICATE_OPERATION_SUCCESS if the operation is completed successfully
+     *      AGPS_CERTIFICATE_ERROR_TOO_MANY_CERTIFICATES if the HAL cannot store the number of
+     *          certificates attempted to be installed, the state of the certificates stored should
+     *          remain the same as before on this error case.
+     *
+     * IMPORTANT:
+     *      If needed the HAL should find out internally the set of certificates that need to be
+     *      removed to accommodate the certificates to install.
+     */
+    int  (*install_certificates) ( const DerEncodedCertificate* certificates, size_t length );
+
+    /**
+     * Notifies the HAL that a list of certificates used for SUPL connections are revoked. It is
+     * expected that the given set of certificates is removed from the internal store of the HAL.
+     *
+     * Parameters:
+     *      fingerprints - A pointer to an array of SHA1 Fingerprints to identify the set of
+     *                     certificates to revoke.
+     *      length - The number of fingerprints provided.
+     * Returns:
+     *      AGPS_CERTIFICATE_OPERATION_SUCCESS if the operation is completed successfully.
+     *
+     * IMPORTANT:
+     *      If any of the certificates provided (through its fingerprint) is not known by the HAL,
+     *      it should be ignored and continue revoking/deleting the rest of them.
+     */
+    int  (*revoke_certificates) ( const Sha1CertificateFingerprint* fingerprints, size_t length );
+} SuplCertificateInterface;
+
+/** Represents an NI request */
+typedef struct {
+    /** set to sizeof(GpsNiNotification) */
+    size_t          size;
+
+    /**
+     * An ID generated by HAL to associate NI notifications and UI
+     * responses
+     */
+    int             notification_id;
+
+    /**
+     * An NI type used to distinguish different categories of NI
+     * events, such as GPS_NI_TYPE_VOICE, GPS_NI_TYPE_UMTS_SUPL, ...
+     */
+    GpsNiType       ni_type;
+
+    /**
+     * Notification/verification options, combinations of GpsNiNotifyFlags constants
+     */
+    GpsNiNotifyFlags notify_flags;
+
+    /**
+     * Timeout period to wait for user response.
+     * Set to 0 for no time out limit.
+     */
+    int             timeout;
+
+    /**
+     * Default response when time out.
+     */
+    GpsUserResponseType default_response;
+
+    /**
+     * Requestor ID
+     */
+    char            requestor_id[GPS_NI_SHORT_STRING_MAXLEN];
+
+    /**
+     * Notification message. It can also be used to store client_id in some cases
+     */
+    char            text[GPS_NI_LONG_STRING_MAXLEN];
+
+    /**
+     * Client name decoding scheme
+     */
+    GpsNiEncodingType requestor_id_encoding;
+
+    /**
+     * Client name decoding scheme
+     */
+    GpsNiEncodingType text_encoding;
+
+    /**
+     * A pointer to extra data. Format:
+     * key_1 = value_1
+     * key_2 = value_2
+     */
+    char           extras[GPS_NI_LONG_STRING_MAXLEN];
+
+} GpsNiNotification;
+
+/**
+ * Callback with NI notification. Can only be called from a thread created by
+ * create_thread_cb.
+ */
+typedef void (*gps_ni_notify_callback)(GpsNiNotification *notification);
+
+/** GPS NI callback structure. */
+typedef struct
+{
+    /**
+     * Sends the notification request from HAL to GPSLocationProvider.
+     */
+    gps_ni_notify_callback notify_cb;
+    gps_create_thread create_thread_cb;
+} GpsNiCallbacks;
+
+/**
+ * Extended interface for Network-initiated (NI) support.
+ */
+typedef struct
+{
+    /** set to sizeof(GpsNiInterface) */
+    size_t          size;
+
+   /** Registers the callbacks for HAL to use. */
+   void (*init) (GpsNiCallbacks *callbacks);
+
+   /** Sends a response to HAL. */
+   void (*respond) (int notif_id, GpsUserResponseType user_response);
+} GpsNiInterface;
+
+#if defined(__ANDROID_OS__)
+struct gps_device_t {
+    struct hw_device_t common;
+
+    /**
+     * Set the provided lights to the provided values.
+     *
+     * Returns: 0 on succes, error code on failure.
+     */
+    const GpsInterface* (*get_gps_interface)(struct gps_device_t* dev);
+};
+#elif defined(__LINUX_OS__)
+struct gps_device_t {
+    const GpsInterface* (*get_gps_interface)(struct gps_device_t* dev);
+};
+#endif
+
+#define AGPS_RIL_REQUEST_REFLOC_CELLID  (1<<0L)
+#define AGPS_RIL_REQUEST_REFLOC_MAC     (1<<1L)
+
+typedef void (*agps_ril_request_set_id)(uint32_t flags);
+typedef void (*agps_ril_request_ref_loc)(uint32_t flags);
+
+typedef struct {
+    agps_ril_request_set_id request_setid;
+    agps_ril_request_ref_loc request_refloc;
+    gps_create_thread create_thread_cb;
+} AGpsRilCallbacks;
+
+/** Extended interface for AGPS_RIL support. */
+typedef struct {
+    /** set to sizeof(AGpsRilInterface) */
+    size_t          size;
+    /**
+     * Opens the AGPS interface and provides the callback routines
+     * to the implementation of this interface.
+     */
+    void  (*init)( AGpsRilCallbacks* callbacks );
+
+    /**
+     * Sets the reference location.
+     */
+    void (*set_ref_location) (const AGpsRefLocation *agps_reflocation, size_t sz_struct);
+    /**
+     * Sets the set ID.
+     */
+    void (*set_set_id) (AGpsSetIDType type, const char* setid);
+
+    /**
+     * Send network initiated message.
+     */
+    void (*ni_message) (uint8_t *msg, size_t len);
+
+    /**
+     * Notify GPS of network status changes.
+     * These parameters match values in the android.net.NetworkInfo class.
+     */
+    void (*update_network_state) (int connected, int type, int roaming, const char* extra_info);
+
+    /**
+     * Notify GPS of network status changes.
+     * These parameters match values in the android.net.NetworkInfo class.
+     */
+    void (*update_network_availability) (int avaiable, const char* apn);
+} AGpsRilInterface;
+
+/**
+ * GPS Geofence.
+ *      There are 3 states associated with a Geofence: Inside, Outside, Unknown.
+ * There are 3 transitions: ENTERED, EXITED, UNCERTAIN.
+ *
+ * An example state diagram with confidence level: 95% and Unknown time limit
+ * set as 30 secs is shown below. (confidence level and Unknown time limit are
+ * explained latter)
+ *                         ____________________________
+ *                        |       Unknown (30 secs)   |
+ *                         """"""""""""""""""""""""""""
+ *                            ^ |                  |  ^
+ *                   UNCERTAIN| |ENTERED     EXITED|  |UNCERTAIN
+ *                            | v                  v  |
+ *                        ________    EXITED     _________
+ *                       | Inside | -----------> | Outside |
+ *                       |        | <----------- |         |
+ *                        """"""""    ENTERED    """""""""
+ *
+ * Inside state: We are 95% confident that the user is inside the geofence.
+ * Outside state: We are 95% confident that the user is outside the geofence
+ * Unknown state: Rest of the time.
+ *
+ * The Unknown state is better explained with an example:
+ *
+ *                            __________
+ *                           |         c|
+ *                           |  ___     |    _______
+ *                           |  |a|     |   |   b   |
+ *                           |  """     |    """""""
+ *                           |          |
+ *                            """"""""""
+ * In the diagram above, "a" and "b" are 2 geofences and "c" is the accuracy
+ * circle reported by the GPS subsystem. Now with regard to "b", the system is
+ * confident that the user is outside. But with regard to "a" is not confident
+ * whether it is inside or outside the geofence. If the accuracy remains the
+ * same for a sufficient period of time, the UNCERTAIN transition would be
+ * triggered with the state set to Unknown. If the accuracy improves later, an
+ * appropriate transition should be triggered.  This "sufficient period of time"
+ * is defined by the parameter in the add_geofence_area API.
+ *     In other words, Unknown state can be interpreted as a state in which the
+ * GPS subsystem isn't confident enough that the user is either inside or
+ * outside the Geofence. It moves to Unknown state only after the expiry of the
+ * timeout.
+ *
+ * The geofence callback needs to be triggered for the ENTERED and EXITED
+ * transitions, when the GPS system is confident that the user has entered
+ * (Inside state) or exited (Outside state) the Geofence. An implementation
+ * which uses a value of 95% as the confidence is recommended. The callback
+ * should be triggered only for the transitions requested by the
+ * add_geofence_area call.
+ *
+ * Even though the diagram and explanation talks about states and transitions,
+ * the callee is only interested in the transistions. The states are mentioned
+ * here for illustrative purposes.
+ *
+ * Startup Scenario: When the device boots up, if an application adds geofences,
+ * and then we get an accurate GPS location fix, it needs to trigger the
+ * appropriate (ENTERED or EXITED) transition for every Geofence it knows about.
+ * By default, all the Geofences will be in the Unknown state.
+ *
+ * When the GPS system is unavailable, gps_geofence_status_callback should be
+ * called to inform the upper layers of the same. Similarly, when it becomes
+ * available the callback should be called. This is a global state while the
+ * UNKNOWN transition described above is per geofence.
+ *
+ * An important aspect to note is that users of this API (framework), will use
+ * other subsystems like wifi, sensors, cell to handle Unknown case and
+ * hopefully provide a definitive state transition to the third party
+ * application. GPS Geofence will just be a signal indicating what the GPS
+ * subsystem knows about the Geofence.
+ *
+ */
+#define GPS_GEOFENCE_ENTERED     (1<<0L)
+#define GPS_GEOFENCE_EXITED      (1<<1L)
+#define GPS_GEOFENCE_UNCERTAIN   (1<<2L)
+
+#define GPS_GEOFENCE_UNAVAILABLE (1<<0L)
+#define GPS_GEOFENCE_AVAILABLE   (1<<1L)
+
+#define GPS_GEOFENCE_OPERATION_SUCCESS           0
+#define GPS_GEOFENCE_ERROR_TOO_MANY_GEOFENCES -100
+#define GPS_GEOFENCE_ERROR_ID_EXISTS          -101
+#define GPS_GEOFENCE_ERROR_ID_UNKNOWN         -102
+#define GPS_GEOFENCE_ERROR_INVALID_TRANSITION -103
+#define GPS_GEOFENCE_ERROR_GENERIC            -149
+
+/**
+ * The callback associated with the geofence.
+ * Parameters:
+ *      geofence_id - The id associated with the add_geofence_area.
+ *      location    - The current GPS location.
+ *      transition  - Can be one of GPS_GEOFENCE_ENTERED, GPS_GEOFENCE_EXITED,
+ *                    GPS_GEOFENCE_UNCERTAIN.
+ *      timestamp   - Timestamp when the transition was detected.
+ *
+ * The callback should only be called when the caller is interested in that
+ * particular transition. For instance, if the caller is interested only in
+ * ENTERED transition, then the callback should NOT be called with the EXITED
+ * transition.
+ *
+ * IMPORTANT: If a transition is triggered resulting in this callback, the GPS
+ * subsystem will wake up the application processor, if its in suspend state.
+ */
+typedef void (*gps_geofence_transition_callback) (int32_t geofence_id,  GpsLocation* location,
+        int32_t transition, GpsUtcTime timestamp);
+
+/**
+ * The callback associated with the availability of the GPS system for geofencing
+ * monitoring. If the GPS system determines that it cannot monitor geofences
+ * because of lack of reliability or unavailability of the GPS signals, it will
+ * call this callback with GPS_GEOFENCE_UNAVAILABLE parameter.
+ *
+ * Parameters:
+ *  status - GPS_GEOFENCE_UNAVAILABLE or GPS_GEOFENCE_AVAILABLE.
+ *  last_location - Last known location.
+ */
+typedef void (*gps_geofence_status_callback) (int32_t status, GpsLocation* last_location);
+
+/**
+ * The callback associated with the add_geofence call.
+ *
+ * Parameter:
+ * geofence_id - Id of the geofence.
+ * status - GPS_GEOFENCE_OPERATION_SUCCESS
+ *          GPS_GEOFENCE_ERROR_TOO_MANY_GEOFENCES  - geofence limit has been reached.
+ *          GPS_GEOFENCE_ERROR_ID_EXISTS  - geofence with id already exists
+ *          GPS_GEOFENCE_ERROR_INVALID_TRANSITION - the monitorTransition contains an
+ *              invalid transition
+ *          GPS_GEOFENCE_ERROR_GENERIC - for other errors.
+ */
+typedef void (*gps_geofence_add_callback) (int32_t geofence_id, int32_t status);
+
+/**
+ * The callback associated with the remove_geofence call.
+ *
+ * Parameter:
+ * geofence_id - Id of the geofence.
+ * status - GPS_GEOFENCE_OPERATION_SUCCESS
+ *          GPS_GEOFENCE_ERROR_ID_UNKNOWN - for invalid id
+ *          GPS_GEOFENCE_ERROR_GENERIC for others.
+ */
+typedef void (*gps_geofence_remove_callback) (int32_t geofence_id, int32_t status);
+
+
+/**
+ * The callback associated with the pause_geofence call.
+ *
+ * Parameter:
+ * geofence_id - Id of the geofence.
+ * status - GPS_GEOFENCE_OPERATION_SUCCESS
+ *          GPS_GEOFENCE_ERROR_ID_UNKNOWN - for invalid id
+ *          GPS_GEOFENCE_ERROR_INVALID_TRANSITION -
+ *                    when monitor_transitions is invalid
+ *          GPS_GEOFENCE_ERROR_GENERIC for others.
+ */
+typedef void (*gps_geofence_pause_callback) (int32_t geofence_id, int32_t status);
+
+/**
+ * The callback associated with the resume_geofence call.
+ *
+ * Parameter:
+ * geofence_id - Id of the geofence.
+ * status - GPS_GEOFENCE_OPERATION_SUCCESS
+ *          GPS_GEOFENCE_ERROR_ID_UNKNOWN - for invalid id
+ *          GPS_GEOFENCE_ERROR_GENERIC for others.
+ */
+typedef void (*gps_geofence_resume_callback) (int32_t geofence_id, int32_t status);
+
+typedef struct {
+    gps_geofence_transition_callback geofence_transition_callback;
+    gps_geofence_status_callback geofence_status_callback;
+    gps_geofence_add_callback geofence_add_callback;
+    gps_geofence_remove_callback geofence_remove_callback;
+    gps_geofence_pause_callback geofence_pause_callback;
+    gps_geofence_resume_callback geofence_resume_callback;
+    gps_create_thread create_thread_cb;
+} GpsGeofenceCallbacks;
+
+/** Extended interface for GPS_Geofencing support */
+typedef struct {
+   /** set to sizeof(GpsGeofencingInterface) */
+   size_t          size;
+
+   /**
+    * Opens the geofence interface and provides the callback routines
+    * to the implementation of this interface.
+    */
+   void  (*init)( GpsGeofenceCallbacks* callbacks );
+
+   /**
+    * Add a geofence area. This api currently supports circular geofences.
+    * Parameters:
+    *    geofence_id - The id for the geofence. If a geofence with this id
+    *       already exists, an error value (GPS_GEOFENCE_ERROR_ID_EXISTS)
+    *       should be returned.
+    *    latitude, longtitude, radius_meters - The lat, long and radius
+    *       (in meters) for the geofence
+    *    last_transition - The current state of the geofence. For example, if
+    *       the system already knows that the user is inside the geofence,
+    *       this will be set to GPS_GEOFENCE_ENTERED. In most cases, it
+    *       will be GPS_GEOFENCE_UNCERTAIN.
+    *    monitor_transition - Which transitions to monitor. Bitwise OR of
+    *       GPS_GEOFENCE_ENTERED, GPS_GEOFENCE_EXITED and
+    *       GPS_GEOFENCE_UNCERTAIN.
+    *    notification_responsiveness_ms - Defines the best-effort description
+    *       of how soon should the callback be called when the transition
+    *       associated with the Geofence is triggered. For instance, if set
+    *       to 1000 millseconds with GPS_GEOFENCE_ENTERED, the callback
+    *       should be called 1000 milliseconds within entering the geofence.
+    *       This parameter is defined in milliseconds.
+    *       NOTE: This is not to be confused with the rate that the GPS is
+    *       polled at. It is acceptable to dynamically vary the rate of
+    *       sampling the GPS for power-saving reasons; thus the rate of
+    *       sampling may be faster or slower than this.
+    *    unknown_timer_ms - The time limit after which the UNCERTAIN transition
+    *       should be triggered. This parameter is defined in milliseconds.
+    *       See above for a detailed explanation.
+    */
+   void (*add_geofence_area) (int32_t geofence_id, double latitude, double longitude,
+       double radius_meters, int last_transition, int monitor_transitions,
+       int notification_responsiveness_ms, int unknown_timer_ms);
+
+   /**
+    * Pause monitoring a particular geofence.
+    * Parameters:
+    *   geofence_id - The id for the geofence.
+    */
+   void (*pause_geofence) (int32_t geofence_id);
+
+   /**
+    * Resume monitoring a particular geofence.
+    * Parameters:
+    *   geofence_id - The id for the geofence.
+    *   monitor_transitions - Which transitions to monitor. Bitwise OR of
+    *       GPS_GEOFENCE_ENTERED, GPS_GEOFENCE_EXITED and
+    *       GPS_GEOFENCE_UNCERTAIN.
+    *       This supersedes the value associated provided in the
+    *       add_geofence_area call.
+    */
+   void (*resume_geofence) (int32_t geofence_id, int monitor_transitions);
+
+   /**
+    * Remove a geofence area. After the function returns, no notifications
+    * should be sent.
+    * Parameter:
+    *   geofence_id - The id for the geofence.
+    */
+   void (*remove_geofence_area) (int32_t geofence_id);
+} GpsGeofencingInterface;
+
+/**
+ * Legacy struct to represent an estimate of the GPS clock time.
+ * Deprecated, to be removed in the next Android release.
+ * Use GnssClock instead.
+ */
+typedef struct {
+    /** set to sizeof(GpsClock) */
+    size_t size;
+    GpsClockFlags flags;
+    int16_t leap_second;
+    GpsClockType type;
+    int64_t time_ns;
+    double time_uncertainty_ns;
+    int64_t full_bias_ns;
+    double bias_ns;
+    double bias_uncertainty_ns;
+    double drift_nsps;
+    double drift_uncertainty_nsps;
+} GpsClock;
+
+/**
+ * Represents an estimate of the GPS clock time.
+ */
+typedef struct {
+    /** set to sizeof(GnssClock) */
+    size_t size;
+
+    /**
+     * A set of flags indicating the validity of the fields in this data
+     * structure.
+     */
+    GnssClockFlags flags;
+
+    /**
+     * Leap second data.
+     * The sign of the value is defined by the following equation:
+     *      utc_time_ns = time_ns - (full_bias_ns + bias_ns) - leap_second *
+     *      1,000,000,000
+     *
+     * If the data is available 'flags' must contain GNSS_CLOCK_HAS_LEAP_SECOND.
+     */
+    int16_t leap_second;
+
+    /**
+     * The GNSS receiver internal clock value. This is the local hardware clock
+     * value.
+     *
+     * For local hardware clock, this value is expected to be monotonically
+     * increasing while the hardware clock remains power on. (For the case of a
+     * HW clock that is not continuously on, see the
+     * hw_clock_discontinuity_count field). The receiver's estimate of GPS time
+     * can be derived by substracting the sum of full_bias_ns and bias_ns (when
+     * available) from this value.
+     *
+     * This GPS time is expected to be the best estimate of current GPS time
+     * that GNSS receiver can achieve.
+     *
+     * Sub-nanosecond accuracy can be provided by means of the 'bias_ns' field.
+     * The value contains the 'time uncertainty' in it.
+     *
+     * This field is mandatory.
+     */
+    int64_t time_ns;
+
+    /**
+     * 1-Sigma uncertainty associated with the clock's time in nanoseconds.
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * If the data is available, 'flags' must contain
+     * GNSS_CLOCK_HAS_TIME_UNCERTAINTY. This value is effectively zero (it is
+     * the reference local clock, by which all other times and time
+     * uncertainties are measured.)  (And thus this field can be not provided,
+     * per GNSS_CLOCK_HAS_TIME_UNCERTAINTY flag, or provided & set to 0.)
+     */
+    double time_uncertainty_ns;
+
+    /**
+     * The difference between hardware clock ('time' field) inside GPS receiver
+     * and the true GPS time since 0000Z, January 6, 1980, in nanoseconds.
+     *
+     * The sign of the value is defined by the following equation:
+     *      local estimate of GPS time = time_ns - (full_bias_ns + bias_ns)
+     *
+     * This value is mandatory if the receiver has estimated GPS time. If the
+     * computed time is for a non-GPS constellation, the time offset of that
+     * constellation to GPS has to be applied to fill this value. The error
+     * estimate for the sum of this and the bias_ns is the bias_uncertainty_ns,
+     * and the caller is responsible for using this uncertainty (it can be very
+     * large before the GPS time has been solved for.) If the data is available
+     * 'flags' must contain GNSS_CLOCK_HAS_FULL_BIAS.
+     */
+    int64_t full_bias_ns;
+
+    /**
+     * Sub-nanosecond bias.
+     * The error estimate for the sum of this and the full_bias_ns is the
+     * bias_uncertainty_ns
+     *
+     * If the data is available 'flags' must contain GNSS_CLOCK_HAS_BIAS. If GPS
+     * has computed a position fix. This value is mandatory if the receiver has
+     * estimated GPS time.
+     */
+    double bias_ns;
+
+    /**
+     * 1-Sigma uncertainty associated with the local estimate of GPS time (clock
+     * bias) in nanoseconds. The uncertainty is represented as an absolute
+     * (single sided) value.
+     *
+     * If the data is available 'flags' must contain
+     * GNSS_CLOCK_HAS_BIAS_UNCERTAINTY. This value is mandatory if the receiver
+     * has estimated GPS time.
+     */
+    double bias_uncertainty_ns;
+
+    /**
+     * The clock's drift in nanoseconds (per second).
+     *
+     * A positive value means that the frequency is higher than the nominal
+     * frequency, and that the (full_bias_ns + bias_ns) is growing more positive
+     * over time.
+     *
+     * The value contains the 'drift uncertainty' in it.
+     * If the data is available 'flags' must contain GNSS_CLOCK_HAS_DRIFT.
+     *
+     * This value is mandatory if the receiver has estimated GNSS time
+     */
+    double drift_nsps;
+
+    /**
+     * 1-Sigma uncertainty associated with the clock's drift in nanoseconds (per second).
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * If the data is available 'flags' must contain
+     * GNSS_CLOCK_HAS_DRIFT_UNCERTAINTY. If GPS has computed a position fix this
+     * field is mandatory and must be populated.
+     */
+    double drift_uncertainty_nsps;
+
+    /**
+     * When there are any discontinuities in the HW clock, this field is
+     * mandatory.
+     *
+     * A "discontinuity" is meant to cover the case of a switch from one source
+     * of clock to another.  A single free-running crystal oscillator (XO)
+     * should generally not have any discontinuities, and this can be set and
+     * left at 0.
+     *
+     * If, however, the time_ns value (HW clock) is derived from a composite of
+     * sources, that is not as smooth as a typical XO, or is otherwise stopped &
+     * restarted, then this value shall be incremented each time a discontinuity
+     * occurs.  (E.g. this value may start at zero at device boot-up and
+     * increment each time there is a change in clock continuity. In the
+     * unlikely event that this value reaches full scale, rollover (not
+     * clamping) is required, such that this value continues to change, during
+     * subsequent discontinuity events.)
+     *
+     * While this number stays the same, between GnssClock reports, it can be
+     * safely assumed that the time_ns value has been running continuously, e.g.
+     * derived from a single, high quality clock (XO like, or better, that's
+     * typically used during continuous GNSS signal sampling.)
+     *
+     * It is expected, esp. during periods where there are few GNSS signals
+     * available, that the HW clock be discontinuity-free as long as possible,
+     * as this avoids the need to use (waste) a GNSS measurement to fully
+     * re-solve for the GPS clock bias and drift, when using the accompanying
+     * measurements, from consecutive GnssData reports.
+     */
+    uint32_t hw_clock_discontinuity_count;
+
+} GnssClock;
+
+/**
+ * Legacy struct to represent a GPS Measurement, it contains raw and computed
+ * information.
+ * Deprecated, to be removed in the next Android release.
+ * Use GnssMeasurement instead.
+ */
+typedef struct {
+    /** set to sizeof(GpsMeasurement) */
+    size_t size;
+    GpsMeasurementFlags flags;
+    int8_t prn;
+    double time_offset_ns;
+    GpsMeasurementState state;
+    int64_t received_gps_tow_ns;
+    int64_t received_gps_tow_uncertainty_ns;
+    double c_n0_dbhz;
+    double pseudorange_rate_mps;
+    double pseudorange_rate_uncertainty_mps;
+    GpsAccumulatedDeltaRangeState accumulated_delta_range_state;
+    double accumulated_delta_range_m;
+    double accumulated_delta_range_uncertainty_m;
+    double pseudorange_m;
+    double pseudorange_uncertainty_m;
+    double code_phase_chips;
+    double code_phase_uncertainty_chips;
+    float carrier_frequency_hz;
+    int64_t carrier_cycles;
+    double carrier_phase;
+    double carrier_phase_uncertainty;
+    GpsLossOfLock loss_of_lock;
+    int32_t bit_number;
+    int16_t time_from_last_bit_ms;
+    double doppler_shift_hz;
+    double doppler_shift_uncertainty_hz;
+    GpsMultipathIndicator multipath_indicator;
+    double snr_db;
+    double elevation_deg;
+    double elevation_uncertainty_deg;
+    double azimuth_deg;
+    double azimuth_uncertainty_deg;
+    bool used_in_fix;
+} GpsMeasurement;
+
+/**
+ * Represents a GNSS Measurement, it contains raw and computed information.
+ *
+ * Independence - All signal measurement information (e.g. sv_time,
+ * pseudorange_rate, multipath_indicator) reported in this struct should be
+ * based on GNSS signal measurements only. You may not synthesize measurements
+ * by calculating or reporting expected measurements based on known or estimated
+ * position, velocity, or time.
+ */
+typedef struct {
+    /** set to sizeof(GpsMeasurement) */
+    size_t size;
+
+    /** A set of flags indicating the validity of the fields in this data structure. */
+    GnssMeasurementFlags flags;
+
+    /**
+     * Satellite vehicle ID number, as defined in GnssSvInfo::svid
+     * This is a mandatory value.
+     */
+    int16_t svid;
+
+    /**
+     * Defines the constellation of the given SV. Value should be one of those
+     * GNSS_CONSTELLATION_* constants
+     */
+    GnssConstellationType constellation;
+
+    /**
+     * Time offset at which the measurement was taken in nanoseconds.
+     * The reference receiver's time is specified by GpsData::clock::time_ns and should be
+     * interpreted in the same way as indicated by GpsClock::type.
+     *
+     * The sign of time_offset_ns is given by the following equation:
+     *      measurement time = GpsClock::time_ns + time_offset_ns
+     *
+     * It provides an individual time-stamp for the measurement, and allows sub-nanosecond accuracy.
+     * This is a mandatory value.
+     */
+    double time_offset_ns;
+
+    /**
+     * Per satellite sync state. It represents the current sync state for the associated satellite.
+     * Based on the sync state, the 'received GPS tow' field should be interpreted accordingly.
+     *
+     * This is a mandatory value.
+     */
+    GnssMeasurementState state;
+
+    /**
+     * The received GNSS Time-of-Week at the measurement time, in nanoseconds.
+     * Ensure that this field is independent (see comment at top of
+     * GnssMeasurement struct.)
+     *
+     * For GPS & QZSS, this is:
+     *   Received GPS Time-of-Week at the measurement time, in nanoseconds.
+     *   The value is relative to the beginning of the current GPS week.
+     *
+     *   Given the highest sync state that can be achieved, per each satellite, valid range
+     *   for this field can be:
+     *     Searching       : [ 0       ]   : GNSS_MEASUREMENT_STATE_UNKNOWN
+     *     C/A code lock   : [ 0   1ms ]   : GNSS_MEASUREMENT_STATE_CODE_LOCK is set
+     *     Bit sync        : [ 0  20ms ]   : GNSS_MEASUREMENT_STATE_BIT_SYNC is set
+     *     Subframe sync   : [ 0    6s ]   : GNSS_MEASUREMENT_STATE_SUBFRAME_SYNC is set
+     *     TOW decoded     : [ 0 1week ]   : GNSS_MEASUREMENT_STATE_TOW_DECODED is set
+     *
+     *   Note well: if there is any ambiguity in integer millisecond,
+     *   GNSS_MEASUREMENT_STATE_MSEC_AMBIGUOUS should be set accordingly, in the 'state' field.
+     *
+     *   This value must be populated if 'state' != GNSS_MEASUREMENT_STATE_UNKNOWN.
+     *
+     * For Glonass, this is:
+     *   Received Glonass time of day, at the measurement time in nanoseconds.
+     *
+     *   Given the highest sync state that can be achieved, per each satellite, valid range for
+     *   this field can be:
+     *     Searching       : [ 0       ]   : GNSS_MEASUREMENT_STATE_UNKNOWN
+     *     C/A code lock   : [ 0   1ms ]   : GNSS_MEASUREMENT_STATE_CODE_LOCK is set
+     *     Symbol sync     : [ 0  10ms ]   : GNSS_MEASUREMENT_STATE_SYMBOL_SYNC is set
+     *     Bit sync        : [ 0  20ms ]   : GNSS_MEASUREMENT_STATE_BIT_SYNC is set
+     *     String sync     : [ 0    2s ]   : GNSS_MEASUREMENT_STATE_GLO_STRING_SYNC is set
+     *     Time of day     : [ 0  1day ]   : GNSS_MEASUREMENT_STATE_GLO_TOD_DECODED is set
+     *
+     * For Beidou, this is:
+     *   Received Beidou time of week, at the measurement time in nanoseconds.
+     *
+     *   Given the highest sync state that can be achieved, per each satellite, valid range for
+     *   this field can be:
+     *     Searching    : [ 0       ] : GNSS_MEASUREMENT_STATE_UNKNOWN
+     *     C/A code lock: [ 0   1ms ] : GNSS_MEASUREMENT_STATE_CODE_LOCK is set
+     *     Bit sync (D2): [ 0   2ms ] : GNSS_MEASUREMENT_STATE_BDS_D2_BIT_SYNC is set
+     *     Bit sync (D1): [ 0  20ms ] : GNSS_MEASUREMENT_STATE_BIT_SYNC is set
+     *     Subframe (D2): [ 0  0.6s ] : GNSS_MEASUREMENT_STATE_BDS_D2_SUBFRAME_SYNC is set
+     *     Subframe (D1): [ 0    6s ] : GNSS_MEASUREMENT_STATE_SUBFRAME_SYNC is set
+     *     Time of week : [ 0 1week ] : GNSS_MEASUREMENT_STATE_TOW_DECODED is set
+     *
+     * For Galileo, this is:
+     *   Received Galileo time of week, at the measurement time in nanoseconds.
+     *
+     *     E1BC code lock   : [ 0   4ms ]   : GNSS_MEASUREMENT_STATE_GAL_E1BC_CODE_LOCK is set
+     *     E1C 2nd code lock: [ 0 100ms ]   :
+     *     GNSS_MEASUREMENT_STATE_GAL_E1C_2ND_CODE_LOCK is set
+     *
+     *     E1B page    : [ 0    2s ] : GNSS_MEASUREMENT_STATE_GAL_E1B_PAGE_SYNC is set
+     *     Time of week: [ 0 1week ] : GNSS_MEASUREMENT_STATE_TOW_DECODED is set
+     *
+     * For SBAS, this is:
+     *   Received SBAS time, at the measurement time in nanoseconds.
+     *
+     *   Given the highest sync state that can be achieved, per each satellite,
+     *   valid range for this field can be:
+     *     Searching    : [ 0     ] : GNSS_MEASUREMENT_STATE_UNKNOWN
+     *     C/A code lock: [ 0 1ms ] : GNSS_MEASUREMENT_STATE_CODE_LOCK is set
+     *     Symbol sync  : [ 0 2ms ] : GNSS_MEASUREMENT_STATE_SYMBOL_SYNC is set
+     *     Message      : [ 0  1s ] : GNSS_MEASUREMENT_STATE_SBAS_SYNC is set
+    */
+    int64_t received_sv_time_in_ns;
+
+    /**
+     * 1-Sigma uncertainty of the Received GPS Time-of-Week in nanoseconds.
+     *
+     * This value must be populated if 'state' != GPS_MEASUREMENT_STATE_UNKNOWN.
+     */
+    int64_t received_sv_time_uncertainty_in_ns;
+
+    /**
+     * Carrier-to-noise density in dB-Hz, typically in the range [0, 63].
+     * It contains the measured C/N0 value for the signal at the antenna port.
+     *
+     * This is a mandatory value.
+     */
+    double c_n0_dbhz;
+
+    /**
+     * Pseudorange rate at the timestamp in m/s. The correction of a given
+     * Pseudorange Rate value includes corrections for receiver and satellite
+     * clock frequency errors. Ensure that this field is independent (see
+     * comment at top of GnssMeasurement struct.)
+     *
+     * It is mandatory to provide the 'uncorrected' 'pseudorange rate', and provide GpsClock's
+     * 'drift' field as well (When providing the uncorrected pseudorange rate, do not apply the
+     * corrections described above.)
+     *
+     * The value includes the 'pseudorange rate uncertainty' in it.
+     * A positive 'uncorrected' value indicates that the SV is moving away from the receiver.
+     *
+     * The sign of the 'uncorrected' 'pseudorange rate' and its relation to the sign of 'doppler
+     * shift' is given by the equation:
+     *      pseudorange rate = -k * doppler shift   (where k is a constant)
+     *
+     * This should be the most accurate pseudorange rate available, based on
+     * fresh signal measurements from this channel.
+     *
+     * It is mandatory that this value be provided at typical carrier phase PRR
+     * quality (few cm/sec per second of uncertainty, or better) - when signals
+     * are sufficiently strong & stable, e.g. signals from a GPS simulator at >=
+     * 35 dB-Hz.
+     */
+    double pseudorange_rate_mps;
+
+    /**
+     * 1-Sigma uncertainty of the pseudorange_rate_mps.
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * This is a mandatory value.
+     */
+    double pseudorange_rate_uncertainty_mps;
+
+    /**
+     * Accumulated delta range's state. It indicates whether ADR is reset or there is a cycle slip
+     * (indicating loss of lock).
+     *
+     * This is a mandatory value.
+     */
+    GnssAccumulatedDeltaRangeState accumulated_delta_range_state;
+
+    /**
+     * Accumulated delta range since the last channel reset in meters.
+     * A positive value indicates that the SV is moving away from the receiver.
+     *
+     * The sign of the 'accumulated delta range' and its relation to the sign of 'carrier phase'
+     * is given by the equation:
+     *          accumulated delta range = -k * carrier phase    (where k is a constant)
+     *
+     * This value must be populated if 'accumulated delta range state' != GPS_ADR_STATE_UNKNOWN.
+     * However, it is expected that the data is only accurate when:
+     *      'accumulated delta range state' == GPS_ADR_STATE_VALID.
+     */
+    double accumulated_delta_range_m;
+
+    /**
+     * 1-Sigma uncertainty of the accumulated delta range in meters.
+     * This value must be populated if 'accumulated delta range state' != GPS_ADR_STATE_UNKNOWN.
+     */
+    double accumulated_delta_range_uncertainty_m;
+
+    /**
+     * Carrier frequency at which codes and messages are modulated, it can be L1 or L2.
+     * If the field is not set, the carrier frequency is assumed to be L1.
+     *
+     * If the data is available, 'flags' must contain
+     * GNSS_MEASUREMENT_HAS_CARRIER_FREQUENCY.
+     */
+    float carrier_frequency_hz;
+
+    /**
+     * The number of full carrier cycles between the satellite and the receiver.
+     * The reference frequency is given by the field 'carrier_frequency_hz'.
+     * Indications of possible cycle slips and resets in the accumulation of
+     * this value can be inferred from the accumulated_delta_range_state flags.
+     *
+     * If the data is available, 'flags' must contain
+     * GNSS_MEASUREMENT_HAS_CARRIER_CYCLES.
+     */
+    int64_t carrier_cycles;
+
+    /**
+     * The RF phase detected by the receiver, in the range [0.0, 1.0].
+     * This is usually the fractional part of the complete carrier phase measurement.
+     *
+     * The reference frequency is given by the field 'carrier_frequency_hz'.
+     * The value contains the 'carrier-phase uncertainty' in it.
+     *
+     * If the data is available, 'flags' must contain
+     * GNSS_MEASUREMENT_HAS_CARRIER_PHASE.
+     */
+    double carrier_phase;
+
+    /**
+     * 1-Sigma uncertainty of the carrier-phase.
+     * If the data is available, 'flags' must contain
+     * GNSS_MEASUREMENT_HAS_CARRIER_PHASE_UNCERTAINTY.
+     */
+    double carrier_phase_uncertainty;
+
+    /**
+     * An enumeration that indicates the 'multipath' state of the event.
+     *
+     * The multipath Indicator is intended to report the presence of overlapping
+     * signals that manifest as distorted correlation peaks.
+     *
+     * - if there is a distorted correlation peak shape, report that multipath
+     *   is GNSS_MULTIPATH_INDICATOR_PRESENT.
+     * - if there is not a distorted correlation peak shape, report
+     *   GNSS_MULTIPATH_INDICATOR_NOT_PRESENT
+     * - if signals are too weak to discern this information, report
+     *   GNSS_MULTIPATH_INDICATOR_UNKNOWN
+     *
+     * Example: when doing the standardized overlapping Multipath Performance
+     * test (3GPP TS 34.171) the Multipath indicator should report
+     * GNSS_MULTIPATH_INDICATOR_PRESENT for those signals that are tracked, and
+     * contain multipath, and GNSS_MULTIPATH_INDICATOR_NOT_PRESENT for those
+     * signals that are tracked and do not contain multipath.
+     */
+    GnssMultipathIndicator multipath_indicator;
+
+    /**
+     * Signal-to-noise ratio at correlator output in dB.
+     * If the data is available, 'flags' must contain GNSS_MEASUREMENT_HAS_SNR.
+     * This is the power ratio of the "correlation peak height above the
+     * observed noise floor" to "the noise RMS".
+     */
+    double snr_db;
+} GnssMeasurement;
+
+/**
+ * Legacy struct to represents a reading of GPS measurements.
+ * Deprecated, to be removed in the next Android release.
+ * Use GnssData instead.
+ */
+typedef struct {
+    /** set to sizeof(GpsData) */
+    size_t size;
+    size_t measurement_count;
+    GpsMeasurement measurements[GPS_MAX_MEASUREMENT];
+
+    /** The GPS clock time reading. */
+    GpsClock clock;
+} GpsData;
+
+/**
+ * Represents a reading of GNSS measurements. For devices where GnssSystemInfo's
+ * year_of_hw is set to 2016+, it is mandatory that these be provided, on
+ * request, when the GNSS receiver is searching/tracking signals.
+ *
+ * - Reporting of GPS constellation measurements is mandatory.
+ * - Reporting of all tracked constellations are encouraged.
+ */
+typedef struct {
+    /** set to sizeof(GnssData) */
+    size_t size;
+
+    /** Number of measurements. */
+    size_t measurement_count;
+
+    /** The array of measurements. */
+    GnssMeasurement measurements[GNSS_MAX_MEASUREMENT];
+
+    /** The GPS clock time reading. */
+    GnssClock clock;
+} GnssData;
+
+/**
+ * The legacy callback for to report measurements from the HAL.
+ *
+ * This callback is deprecated, and will be removed in the next release. Use
+ * gnss_measurement_callback() instead.
+ *
+ * Parameters:
+ *    data - A data structure containing the measurements.
+ */
+typedef void (*gps_measurement_callback) (GpsData* data);
+
+/**
+ * The callback for to report measurements from the HAL.
+ *
+ * Parameters:
+ *    data - A data structure containing the measurements.
+ */
+typedef void (*gnss_measurement_callback) (GnssData* data);
+
+typedef struct {
+    /** set to sizeof(GpsMeasurementCallbacks) */
+    size_t size;
+    gps_measurement_callback measurement_callback;
+    gnss_measurement_callback gnss_measurement_callback;
+} GpsMeasurementCallbacks;
+
+/**
+ * Extended interface for GPS Measurements support.
+ */
+typedef struct {
+    /** Set to sizeof(GpsMeasurementInterface) */
+    size_t size;
+
+    /**
+     * Initializes the interface and registers the callback routines with the HAL.
+     * After a successful call to 'init' the HAL must begin to provide updates at its own phase.
+     *
+     * Status:
+     *    GPS_MEASUREMENT_OPERATION_SUCCESS
+     *    GPS_MEASUREMENT_ERROR_ALREADY_INIT - if a callback has already been registered without a
+     *              corresponding call to 'close'
+     *    GPS_MEASUREMENT_ERROR_GENERIC - if any other error occurred, it is expected that the HAL
+     *              will not generate any updates upon returning this error code.
+     */
+    int (*init) (GpsMeasurementCallbacks* callbacks);
+
+    /**
+     * Stops updates from the HAL, and unregisters the callback routines.
+     * After a call to stop, the previously registered callbacks must be considered invalid by the
+     * HAL.
+     * If stop is invoked without a previous 'init', this function should perform no work.
+     */
+    void (*close) ();
+
+} GpsMeasurementInterface;
+
+/**
+ * Legacy struct to represents a GPS navigation message (or a fragment of it).
+ * Deprecated, to be removed in the next Android release.
+ * Use GnssNavigationMessage instead.
+ */
+typedef struct {
+    /** set to sizeof(GpsNavigationMessage) */
+    size_t size;
+    int8_t prn;
+    GpsNavigationMessageType type;
+    NavigationMessageStatus status;
+    int16_t message_id;
+    int16_t submessage_id;
+    size_t data_length;
+    uint8_t* data;
+} GpsNavigationMessage;
+
+/** Represents a GPS navigation message (or a fragment of it). */
+typedef struct {
+    /** set to sizeof(GnssNavigationMessage) */
+    size_t size;
+
+    /**
+     * Satellite vehicle ID number, as defined in GnssSvInfo::svid
+     * This is a mandatory value.
+     */
+    int16_t svid;
+
+    /**
+     * The type of message contained in the structure.
+     * This is a mandatory value.
+     */
+    GnssNavigationMessageType type;
+
+    /**
+     * The status of the received navigation message.
+     * No need to send any navigation message that contains words with parity error and cannot be
+     * corrected.
+     */
+    NavigationMessageStatus status;
+
+    /**
+     * Message identifier. It provides an index so the complete Navigation
+     * Message can be assembled.
+     *
+     * - For GPS L1 C/A subframe 4 and 5, this value corresponds to the 'frame
+     *   id' of the navigation message, in the range of 1-25 (Subframe 1, 2, 3
+     *   does not contain a 'frame id' and this value can be set to -1.)
+     *
+     * - For Glonass L1 C/A, this refers to the frame ID, in the range of 1-5.
+     *
+     * - For BeiDou D1, this refers to the frame number in the range of 1-24
+     *
+     * - For Beidou D2, this refers to the frame number, in the range of 1-120
+     *
+     * - For Galileo F/NAV nominal frame structure, this refers to the subframe
+     *   number, in the range of 1-12
+     *
+     * - For Galileo I/NAV nominal frame structure, this refers to the subframe
+     *   number in the range of 1-24
+     */
+    int16_t message_id;
+
+    /**
+     * Sub-message identifier. If required by the message 'type', this value
+     * contains a sub-index within the current message (or frame) that is being
+     * transmitted.
+     *
+     * - For GPS L1 C/A, BeiDou D1 & BeiDou D2, the submessage id corresponds to
+     *   the subframe number of the navigation message, in the range of 1-5.
+     *
+     * - For Glonass L1 C/A, this refers to the String number, in the range from
+     *   1-15
+     *
+     * - For Galileo F/NAV, this refers to the page type in the range 1-6
+     *
+     * - For Galileo I/NAV, this refers to the word type in the range 1-10+
+     */
+    int16_t submessage_id;
+
+    /**
+     * The length of the data (in bytes) contained in the current message.
+     * If this value is different from zero, 'data' must point to an array of the same size.
+     * e.g. for L1 C/A the size of the sub-frame will be 40 bytes (10 words, 30 bits/word).
+     *
+     * This is a mandatory value.
+     */
+    size_t data_length;
+
+    /**
+     * The data of the reported GPS message. The bytes (or words) specified
+     * using big endian format (MSB first).
+     *
+     * - For GPS L1 C/A, Beidou D1 & Beidou D2, each subframe contains 10 30-bit
+     *   words. Each word (30 bits) should be fit into the last 30 bits in a
+     *   4-byte word (skip B31 and B32), with MSB first, for a total of 40
+     *   bytes, covering a time period of 6, 6, and 0.6 seconds, respectively.
+     *
+     * - For Glonass L1 C/A, each string contains 85 data bits, including the
+     *   checksum.  These bits should be fit into 11 bytes, with MSB first (skip
+     *   B86-B88), covering a time period of 2 seconds.
+     *
+     * - For Galileo F/NAV, each word consists of 238-bit (sync & tail symbols
+     *   excluded). Each word should be fit into 30-bytes, with MSB first (skip
+     *   B239, B240), covering a time period of 10 seconds.
+     *
+     * - For Galileo I/NAV, each page contains 2 page parts, even and odd, with
+     *   a total of 2x114 = 228 bits, (sync & tail excluded) that should be fit
+     *   into 29 bytes, with MSB first (skip B229-B232).
+     */
+    uint8_t* data;
+
+} GnssNavigationMessage;
+
+/**
+ * The legacy callback to report an available fragment of a GPS navigation
+ * messages from the HAL.
+ *
+ * This callback is deprecated, and will be removed in the next release. Use
+ * gnss_navigation_message_callback() instead.
+ *
+ * Parameters:
+ *      message - The GPS navigation submessage/subframe representation.
+ */
+typedef void (*gps_navigation_message_callback) (GpsNavigationMessage* message);
+
+/**
+ * The callback to report an available fragment of a GPS navigation messages from the HAL.
+ *
+ * Parameters:
+ *      message - The GPS navigation submessage/subframe representation.
+ */
+typedef void (*gnss_navigation_message_callback) (GnssNavigationMessage* message);
+
+typedef struct {
+    /** set to sizeof(GpsNavigationMessageCallbacks) */
+    size_t size;
+    gps_navigation_message_callback navigation_message_callback;
+    gnss_navigation_message_callback gnss_navigation_message_callback;
+} GpsNavigationMessageCallbacks;
+
+/**
+ * Extended interface for GPS navigation message reporting support.
+ */
+typedef struct {
+    /** Set to sizeof(GpsNavigationMessageInterface) */
+    size_t size;
+
+    /**
+     * Initializes the interface and registers the callback routines with the HAL.
+     * After a successful call to 'init' the HAL must begin to provide updates as they become
+     * available.
+     *
+     * Status:
+     *      GPS_NAVIGATION_MESSAGE_OPERATION_SUCCESS
+     *      GPS_NAVIGATION_MESSAGE_ERROR_ALREADY_INIT - if a callback has already been registered
+     *              without a corresponding call to 'close'.
+     *      GPS_NAVIGATION_MESSAGE_ERROR_GENERIC - if any other error occurred, it is expected that
+     *              the HAL will not generate any updates upon returning this error code.
+     */
+    int (*init) (GpsNavigationMessageCallbacks* callbacks);
+
+    /**
+     * Stops updates from the HAL, and unregisters the callback routines.
+     * After a call to stop, the previously registered callbacks must be considered invalid by the
+     * HAL.
+     * If stop is invoked without a previous 'init', this function should perform no work.
+     */
+    void (*close) ();
+
+} GpsNavigationMessageInterface;
+
+/**
+ * Interface for passing GNSS configuration contents from platform to HAL.
+ */
+typedef struct {
+    /** Set to sizeof(GnssConfigurationInterface) */
+    size_t size;
+
+    /**
+     * Deliver GNSS configuration contents to HAL.
+     * Parameters:
+     *     config_data - a pointer to a char array which holds what usually is expected from
+                         file(/etc/gps.conf), i.e., a sequence of UTF8 strings separated by '\n'.
+     *     length - total number of UTF8 characters in configuraiton data.
+     *
+     * IMPORTANT:
+     *      GPS HAL should expect this function can be called multiple times. And it may be
+     *      called even when GpsLocationProvider is already constructed and enabled. GPS HAL
+     *      should maintain the existing requests for various callback regardless the change
+     *      in configuration data.
+     */
+    void (*configuration_update) (const char* config_data, int32_t length);
+} GnssConfigurationInterface;
+
+__END_DECLS
+
+#endif
+
+#endif /* ANDROID_INCLUDE_HARDWARE_GPS_H */
+
diff --git a/src/connectivity/gps/gps_hal/hardware/gps_internal.h b/src/connectivity/gps/gps_hal/hardware/gps_internal.h
new file mode 100644
index 0000000..67a16e8
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/hardware/gps_internal.h
@@ -0,0 +1,98 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef ANDROID_INCLUDE_HARDWARE_GPS_INTERNAL_H
+#define ANDROID_INCLUDE_HARDWARE_GPS_INTERNAL_H
+
+#ifdef __LINUX_OS__
+//#include <hardware/gps.h>
+#include "gps.h"
+
+/****************************************************************************
+ * This file contains legacy structs that are deprecated/retired from gps.h *
+ ****************************************************************************/
+
+__BEGIN_DECLS
+
+/**
+ * Legacy GPS callback structure.
+ * Deprecated, to be removed in the next Android release.
+ * Use GpsCallbacks instead.
+ */
+typedef struct {
+    /** set to sizeof(GpsCallbacks_v1) */
+    size_t      size;
+    gps_location_callback location_cb;
+    gps_status_callback status_cb;
+    gps_sv_status_callback sv_status_cb;
+    gps_nmea_callback nmea_cb;
+    gps_set_capabilities set_capabilities_cb;
+    gps_acquire_wakelock acquire_wakelock_cb;
+    gps_release_wakelock release_wakelock_cb;
+    gps_create_thread create_thread_cb;
+    gps_request_utc_time request_utc_time_cb;
+} GpsCallbacks_v1;
+
+#pragma pack(push,4)
+// We need to keep the alignment of this data structure to 4-bytes, to ensure that in 64-bit
+// environments the size of this legacy definition does not collide with _v2. Implementations should
+// be using _v2 and _v3, so it's OK to pay the 'unaligned' penalty in 64-bit if an old
+// implementation is still in use.
+
+/**
+ * Legacy struct to represent the status of AGPS.
+ */
+typedef struct {
+    /** set to sizeof(AGpsStatus_v1) */
+    size_t          size;
+    AGpsType        type;
+    AGpsStatusValue status;
+} AGpsStatus_v1;
+
+#pragma pack(pop)
+
+/**
+ * Legacy struct to represent the status of AGPS augmented with a IPv4 address
+ * field.
+ */
+typedef struct {
+    /** set to sizeof(AGpsStatus_v2) */
+    size_t          size;
+    AGpsType        type;
+    AGpsStatusValue status;
+
+    /*-------------------- New fields in _v2 --------------------*/
+
+    uint32_t        ipaddr;
+} AGpsStatus_v2;
+
+/**
+ * Legacy extended interface for AGPS support.
+ * See AGpsInterface_v2 for more information.
+ */
+typedef struct {
+    /** set to sizeof(AGpsInterface_v1) */
+    size_t          size;
+    void  (*init)( AGpsCallbacks* callbacks );
+    int  (*data_conn_open)( const char* apn );
+    int  (*data_conn_closed)();
+    int  (*data_conn_failed)();
+    int  (*set_server)( AGpsType type, const char* hostname, int port );
+} AGpsInterface_v1;
+
+__END_DECLS
+
+#endif
+#endif /* ANDROID_INCLUDE_HARDWARE_GPS_INTERNAL_H */
diff --git a/src/connectivity/gps/gps_hal/inc/data_coder.h b/src/connectivity/gps/gps_hal/inc/data_coder.h
new file mode 100644
index 0000000..fc66d2f
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/inc/data_coder.h
@@ -0,0 +1,32 @@
+#ifndef __DATA_CODER_H__
+#define __DATA_CODER_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+char        get_byte(char* buff, int* offset, int src_len);
+short       get_short(char* buff, int* offset, int src_len);
+int         get_int(char* buff, int* offset, int src_len);
+long long   get_long(char* buff, int* offset, int src_len);
+float       get_float(char* buff, int* offset, int src_len);
+double      get_double(char* buff, int* offset, int src_len);
+char*       get_string(char* buff, int* offset, int src_len);
+char*       get_string2(char* buff, int* offset, int src_len);
+int         get_binary(char* buff, int* offset, char* output, int src_len, int des_len);
+
+void put_byte(char* buff, int* offset, const char input);
+void put_short(char* buff, int* offset, const short input);
+void put_int(char* buff, int* offset, const int input);
+void put_long(char* buff, int* offset, const long long input);
+void put_float(char* buff, int* offset, const float input);
+void put_double(char* buff, int* offset, const double input);
+void put_string(char* buff, int* offset, const char* input);
+void put_binary(char* buff, int* offset, const char* input, int len);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
diff --git a/src/connectivity/gps/gps_hal/inc/geofencehal_worker.h b/src/connectivity/gps/gps_hal/inc/geofencehal_worker.h
new file mode 100644
index 0000000..e5542dc
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/inc/geofencehal_worker.h
@@ -0,0 +1,142 @@
+#ifndef __GEOFENCE_HAL_WORKER_H__

+#define __GEOFENCE_HAL_WORKER_H__

+

+#ifdef __cplusplus

+extern "C" {

+#endif

+

+#include <stdint.h>

+#include <pthread.h>

+#include "data_coder.h"

+

+#if defined(__ANDROID_OS__)

+#include <hardware/gps.h>

+#elif defined(__LINUX_OS__)

+#include "gps.h"

+#endif

+

+//======================================================

+// GFC(GPS HAL) -> MNL

+//======================================================

+#define GEOFENCE_TO_MNL "gfc_to_mnl"

+#define MNL_TO_GEOFENCE "mnl_to_gfc"

+

+#define HAL_GFC_BUFF_SIZE   (1 * 1024)

+#define MAX_GOEFENCE 30

+#define GEO_CONFIG_MASK_DISABLE_SMD     (1U<<0)

+#ifdef __aarch64__

+#define MTK_64_PLATFORM

+#endif

+

+#define MTK_GFC_SUCCESS     (0)

+#define MTK_GFC_ERROR       (-1)

+#define MTK_GFC_TIMEOUT     (-2)

+

+

+typedef enum {

+    MTK_FLP_MSG_SYS_FLPD_RESET_NTF = 100,

+

+    //HAL messages

+    MTK_FLP_MSG_HAL_INIT_CMD = 200,

+    MTK_FLP_MSG_HAL_START_CMD,

+    MTK_FLP_MSG_HAL_STOP_CMD,

+    MTK_FLP_MSG_HAL_STOP_RSP,

+    MTK_FLP_MSG_HAL_SET_OPTION_CMD,

+    MTK_FLP_MSG_HAL_INJECT_LOC_CMD,

+    MTK_FLP_MSG_HAL_DIAG_INJECT_DATA_NTF,

+    MTK_FLP_MSG_HAL_DIAG_REPORT_DATA_NTF,

+

+    MTK_FLP_MSG_HSB_REPORT_LOC_NTF = 300,

+    MTK_FLP_MSG_OFL_REPORT_LOC_NTF,

+

+    MTK_FLP_MSG_HAL_GEOFENCE_CALLBACK_NTF = 400,

+    MTK_FLP_MSG_HAL_REQUEST_LOC_NTF,

+    MTK_FLP_MSG_HAL_FLUSH_LOC_NTF,

+    MTK_FLP_MSG_HAL_REPORT_STATUS_NTF,

+    MTK_FLP_MSG_OFL_GEOFENCE_CALLBACK_NTF,  //for Offload geofence use

+    MTK_FLP_MSG_OFL_GEOFENCE_CMD,

+

+    MTK_FLP_MSG_DC_START_CMD = 500,

+    MTK_FLP_MSG_DC_STOP_CMD,

+    MTK_FLP_MSG_CONN_SCREEN_STATUS,     //for AP to connsys screen on/off status exchange

+    MTK_FLP_MSG_END,

+}MTK_FLP_MSG_TYPE;

+

+typedef enum {

+    inside,

+    outside,

+    uncertain

+} SET_STATE;

+

+typedef enum {

+    INIT_GEOFENCE,

+    ADD_GEOFENCE_AREA,

+    PAUSE_GEOFENCE,

+    RESUME_GEOFENCE,

+    REMOVE_GEOFENCE,

+    RECOVER_GEOFENCE,

+    CLEAR_GEOFENCE,

+} MTK_GFC_COMMAND_T;

+

+typedef enum {

+    GEOFENCE_ADD_CALLBACK,

+    GEOFENCE_REMOVE_CALLBACK,

+    GEOFENCE_PAUSE_CALLBACK,

+    GEOFENCE_RESUME_CALLBACK

+} GEOFENCE_CALLBACK_T;

+

+typedef struct mtk_geofence_area {

+    int32_t geofence_id;

+    double latitude;

+    double longitude;

+    double radius;

+    float coordinate_dn;

+    float coordinate_de;

+    int last_transition; /*current state, most cases is GPS_GEOFENCE_UNCERTAIN*/

+    int monitor_transition; /*bitwise or of  entered/exited/uncertain*/

+    int notification_period;/*timer  interval, period of report transition status*/

+    int unknown_timer;/*continue positioning time limitied while positioning*/

+    int alive;/*geofence status, 1 alive, 0 sleep*/

+    SET_STATE latest_state;/*latest status: outside, inside, uncertain*/

+    uint32_t config;

+} MTK_GEOFENCE_PROPERTY_T;

+

+typedef struct {

+    int type;

+    int length;

+} MTK_FLP_MSG_T;

+

+typedef struct mtk_geofence_callback {

+    int32_t cb_id;

+    int32_t geofence_id;

+    int32_t result;

+} MTK_GEOFENCE_CALLBACK_T;

+

+

+void hal2_geofence_init();

+int is_gfc_exist();

+void hal2_geofence_add_geofences(const MTK_GEOFENCE_PROPERTY_T dbg_fence);

+void hal2_geofence_pause_geofence(const int32_t geofence_id);

+void hal2_geofence_resume_geofence(const int32_t geofence_id, const int monitor_transitions);

+void hal2_geofence_remove_geofences(const int32_t geofence_id);

+void mtk_geo_inject_info_set(int fence_id, float dn, float de);

+void mtk_geo_inject_info_get(int fence_id, float* dn, float* de);

+int check_buff_fence_exist(const int32_t fence_id);

+int set_buff_transition_fence(const int32_t fence_id, const int transition);

+#ifdef MTK_64_PLATFORM

+void mtk_loc_rearrange(unsigned char *loc_in, GpsLocation *loc_out);

+#endif

+

+//Callbacks to GPS HAL

+void mtk_geofence_transition_callbacks_proc(MTK_FLP_MSG_T *prmsg);

+void mtk_geofence_callbacks_proc(MTK_FLP_MSG_T *prmsg);

+

+

+

+#ifdef __cplusplus

+}

+#endif

+

+#endif

+

+

diff --git a/src/connectivity/gps/gps_hal/inc/gps.h b/src/connectivity/gps/gps_hal/inc/gps.h
new file mode 100644
index 0000000..596499c
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/inc/gps.h
@@ -0,0 +1,2233 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_INCLUDE_HARDWARE_GPS_H
+#define ANDROID_INCLUDE_HARDWARE_GPS_H
+
+#include <stdint.h>
+#include <sys/cdefs.h>
+#include <sys/types.h>
+#include <pthread.h>
+#include <sys/socket.h>
+#include <stdbool.h>
+#ifdef __ANDROID_OS__
+#include <hardware/hardware.h>
+#endif
+__BEGIN_DECLS
+
+/*
+ * Enums defined in HIDL in hardware/interfaces are auto-generated and present
+ * in gnss-base.h.
+ */
+
+/* for compatibility */
+
+/*#define GPS_REQUEST_AGPS_DATA_CONN GNSS_REQUEST_AGNSS_DATA_CONN
+#define GPS_RELEASE_AGPS_DATA_CONN GNSS_RELEASE_AGNSS_DATA_CONN
+#define GPS_AGPS_DATA_CONNECTED GNSS_AGNSS_DATA_CONNECTED
+#define GPS_AGPS_DATA_CONN_DONE GNSS_AGNSS_DATA_CONN_DONE
+#define GPS_AGPS_DATA_CONN_FAILED GNSS_AGNSS_DATA_CONN_FAILED
+#define AGPS_RIL_NETWORK_TYPE_MOBILE_MMS AGPS_RIL_NETWORK_TYPE_MMS
+#define AGPS_RIL_NETWORK_TYPE_MOBILE_SUPL AGPS_RIL_NETWORK_TYPE_SUPL
+#define AGPS_RIL_NETWORK_TTYPE_MOBILE_DUN AGPS_RIL_NETWORK_TYPE_DUN
+#define AGPS_RIL_NETWORK_TTYPE_MOBILE_HIPRI AGPS_RIL_NETWORK_TYPE_HIPRI
+#define AGPS_RIL_NETWORK_TTYPE_WIMAX AGPS_RIL_NETWORK_TYPE_WIMAX
+#define GNSS_MULTIPATH_INDICATOR_NOT_PRESENT GNSS_MULTIPATH_INDICATIOR_NOT_PRESENT
+#define AGPS_SETID_TYPE_MSISDN AGPS_SETID_TYPE_MSISDM
+#define GPS_MEASUREMENT_OPERATION_SUCCESS GPS_MEASUREMENT_SUCCESS
+#define GPS_NAVIGATION_MESSAGE_OPERATION_SUCCESS GPS_NAVIGATION_MESSAGE_SUCCESS
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L1CA GNSS_NAVIGATION_MESSAGE_TYPE_GNSS_L1CA
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L2CNAV GNSS_NAVIGATION_MESSAGE_TYPE_GNSS_L2CNAV
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L5CNAV GNSS_NAVIGATION_MESSAGE_TYPE_GNSS_L5CNAV
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_CNAV2 GNSS_NAVIGATION_MESSAGE_TYPE_GNSS_CNAV2
+#define GPS_LOCATION_HAS_ACCURACY GPS_LOCATION_HAS_HORIZONTAL_ACCURACY
+*/
+/**
+ * The id of this module
+ */
+#define GPS_HARDWARE_MODULE_ID "gps"
+
+#define GPS_NAVIGATION_MESSAGE_OPERATION_SUCCESS             0
+#define GPS_NAVIGATION_MESSAGE_ERROR_ALREADY_INIT         -100
+#define GPS_NAVIGATION_MESSAGE_ERROR_GENERIC              -101
+
+/** Milliseconds since January 1, 1970 */
+typedef int64_t GpsUtcTime;
+
+/** Maximum number of SVs for gps_sv_status_callback(). */
+#define GPS_MAX_SVS 32
+/** Maximum number of SVs for gps_sv_status_callback(). */
+#define GNSS_MAX_SVS 64
+
+/** Maximum number of Measurements in gps_measurement_callback(). */
+#define GPS_MAX_MEASUREMENT   32
+
+/** Maximum number of Measurements in gnss_measurement_callback(). */
+#define GNSS_MAX_MEASUREMENT   64
+
+/** Requested operational mode for GPS operation. */
+typedef uint32_t GpsPositionMode;
+/* IMPORTANT: Note that the following values must match
+ * constants in GpsLocationProvider.java. */
+/** Mode for running GPS standalone (no assistance). */
+#define GPS_POSITION_MODE_STANDALONE    0
+/** AGPS MS-Based mode. */
+#define GPS_POSITION_MODE_MS_BASED      1
+/**
+ * AGPS MS-Assisted mode. This mode is not maintained by the platform anymore.
+ * It is strongly recommended to use GPS_POSITION_MODE_MS_BASED instead.
+ */
+#define GPS_POSITION_MODE_MS_ASSISTED   2
+
+/** Requested recurrence mode for GPS operation. */
+typedef uint32_t GpsPositionRecurrence;
+/* IMPORTANT: Note that the following values must match
+ * constants in GpsLocationProvider.java. */
+/** Receive GPS fixes on a recurring basis at a specified period. */
+#define GPS_POSITION_RECURRENCE_PERIODIC    0
+/** Request a single shot GPS fix. */
+#define GPS_POSITION_RECURRENCE_SINGLE      1
+
+/** GPS status event values. */
+typedef uint16_t GpsStatusValue;
+/* IMPORTANT: Note that the following values must match
+ * constants in GpsLocationProvider.java. */
+/** GPS status unknown. */
+#define GPS_STATUS_NONE             0
+/** GPS has begun navigating. */
+#define GPS_STATUS_SESSION_BEGIN    1
+/** GPS has stopped navigating. */
+#define GPS_STATUS_SESSION_END      2
+/** GPS has powered on but is not navigating. */
+#define GPS_STATUS_ENGINE_ON        3
+/** GPS is powered off. */
+#define GPS_STATUS_ENGINE_OFF       4
+
+/** Flags to indicate which values are valid in a GpsLocation. */
+typedef uint16_t GpsLocationFlags;
+/* IMPORTANT: Note that the following values must match
+ * constants in GpsLocationProvider.java. */
+/** GpsLocation has valid latitude and longitude. */
+#define GPS_LOCATION_HAS_LAT_LONG   0x0001
+/** GpsLocation has valid altitude. */
+#define GPS_LOCATION_HAS_ALTITUDE   0x0002
+/** GpsLocation has valid speed. */
+#define GPS_LOCATION_HAS_SPEED      0x0004
+/** GpsLocation has valid bearing. */
+#define GPS_LOCATION_HAS_BEARING    0x0008
+/** GpsLocation has valid accuracy. */
+#define GPS_LOCATION_HAS_ACCURACY   0x0010
+
+/**
+ * GPS HAL schedules fixes for GPS_POSITION_RECURRENCE_PERIODIC mode. If this is
+ * not set, then the framework will use 1000ms for min_interval and will start
+ * and call start() and stop() to schedule the GPS.
+ */
+#define GPS_CAPABILITY_SCHEDULING       (1 << 0)
+/** GPS supports MS-Based AGPS mode */
+#define GPS_CAPABILITY_MSB              (1 << 1)
+/** GPS supports MS-Assisted AGPS mode */
+#define GPS_CAPABILITY_MSA              (1 << 2)
+/** GPS supports single-shot fixes */
+#define GPS_CAPABILITY_SINGLE_SHOT      (1 << 3)
+/** GPS supports on demand time injection */
+#define GPS_CAPABILITY_ON_DEMAND_TIME   (1 << 4)
+/** GPS supports Geofencing  */
+#define GPS_CAPABILITY_GEOFENCING       (1 << 5)
+/** GPS supports Measurements. */
+#define GPS_CAPABILITY_MEASUREMENTS     (1 << 6)
+/** GPS supports Navigation Messages */
+#define GPS_CAPABILITY_NAV_MESSAGES     (1 << 7)
+
+/**
+ * Flags used to specify which aiding data to delete when calling
+ * delete_aiding_data().
+ */
+typedef uint16_t GpsAidingData;
+/* IMPORTANT: Note that the following values must match
+ * constants in GpsLocationProvider.java. */
+#define GPS_DELETE_EPHEMERIS        0x0001
+#define GPS_DELETE_ALMANAC          0x0002
+#define GPS_DELETE_POSITION         0x0004
+#define GPS_DELETE_TIME             0x0008
+#define GPS_DELETE_IONO             0x0010
+#define GPS_DELETE_UTC              0x0020
+#define GPS_DELETE_HEALTH           0x0040
+#define GPS_DELETE_SVDIR            0x0080
+#define GPS_DELETE_SVSTEER          0x0100
+#define GPS_DELETE_SADATA           0x0200
+#define GPS_DELETE_RTI              0x0400
+#define GPS_DELETE_CELLDB_INFO      0x8000
+#define GPS_DELETE_ALL              0xFFFF
+
+/** AGPS type */
+typedef uint16_t AGpsType;
+#define AGPS_TYPE_SUPL          1
+#define AGPS_TYPE_C2K           2
+
+typedef uint16_t AGpsSetIDType;
+#define AGPS_SETID_TYPE_NONE    0
+#define AGPS_SETID_TYPE_IMSI    1
+#define AGPS_SETID_TYPE_MSISDN  2
+
+typedef uint16_t ApnIpType;
+#define APN_IP_INVALID          0
+#define APN_IP_IPV4             1
+#define APN_IP_IPV6             2
+#define APN_IP_IPV4V6           3
+
+/**
+ * String length constants
+ */
+#define GPS_NI_SHORT_STRING_MAXLEN      256
+#define GPS_NI_LONG_STRING_MAXLEN       2048
+
+/**
+ * GpsNiType constants
+ */
+typedef uint32_t GpsNiType;
+#define GPS_NI_TYPE_VOICE              1
+#define GPS_NI_TYPE_UMTS_SUPL          2
+#define GPS_NI_TYPE_UMTS_CTRL_PLANE    3
+
+/**
+ * GpsNiNotifyFlags constants
+ */
+typedef uint32_t GpsNiNotifyFlags;
+/** NI requires notification */
+#define GPS_NI_NEED_NOTIFY          0x0001
+/** NI requires verification */
+#define GPS_NI_NEED_VERIFY          0x0002
+/** NI requires privacy override, no notification/minimal trace */
+#define GPS_NI_PRIVACY_OVERRIDE     0x0004
+
+/**
+ * GPS NI responses, used to define the response in
+ * NI structures
+ */
+typedef int GpsUserResponseType;
+#define GPS_NI_RESPONSE_ACCEPT         1
+#define GPS_NI_RESPONSE_DENY           2
+#define GPS_NI_RESPONSE_NORESP         3
+
+/**
+ * NI data encoding scheme
+ */
+typedef int GpsNiEncodingType;
+#define GPS_ENC_NONE                   0
+#define GPS_ENC_SUPL_GSM_DEFAULT       1
+#define GPS_ENC_SUPL_UTF8              2
+#define GPS_ENC_SUPL_UCS2              3
+#define GPS_ENC_UNKNOWN                -1
+
+/** AGPS status event values. */
+typedef uint16_t AGpsStatusValue;
+/** GPS requests data connection for AGPS. */
+#define GPS_REQUEST_AGPS_DATA_CONN  1
+/** GPS releases the AGPS data connection. */
+#define GPS_RELEASE_AGPS_DATA_CONN  2
+/** AGPS data connection initiated */
+#define GPS_AGPS_DATA_CONNECTED     3
+/** AGPS data connection completed */
+#define GPS_AGPS_DATA_CONN_DONE     4
+/** AGPS data connection failed */
+#define GPS_AGPS_DATA_CONN_FAILED   5
+
+typedef uint16_t AGpsRefLocationType;
+#define AGPS_REF_LOCATION_TYPE_GSM_CELLID   1
+#define AGPS_REF_LOCATION_TYPE_UMTS_CELLID  2
+#define AGPS_REF_LOCATION_TYPE_MAC          3
+#define AGPS_REF_LOCATION_TYPE_LTE_CELLID   4
+
+/* Deprecated, to be removed in the next Android release. */
+#define AGPS_REG_LOCATION_TYPE_MAC          3
+
+/** Network types for update_network_state "type" parameter */
+#define AGPS_RIL_NETWORK_TYPE_MOBILE        0
+#define AGPS_RIL_NETWORK_TYPE_WIFI          1
+#define AGPS_RIL_NETWORK_TYPE_MOBILE_MMS    2
+#define AGPS_RIL_NETWORK_TYPE_MOBILE_SUPL   3
+#define AGPS_RIL_NETWORK_TTYPE_MOBILE_DUN   4
+#define AGPS_RIL_NETWORK_TTYPE_MOBILE_HIPRI 5
+#define AGPS_RIL_NETWORK_TTYPE_WIMAX        6
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. */
+typedef uint16_t GpsClockFlags;
+#define GPS_CLOCK_HAS_LEAP_SECOND               (1<<0)
+#define GPS_CLOCK_HAS_TIME_UNCERTAINTY          (1<<1)
+#define GPS_CLOCK_HAS_FULL_BIAS                 (1<<2)
+#define GPS_CLOCK_HAS_BIAS                      (1<<3)
+#define GPS_CLOCK_HAS_BIAS_UNCERTAINTY          (1<<4)
+#define GPS_CLOCK_HAS_DRIFT                     (1<<5)
+#define GPS_CLOCK_HAS_DRIFT_UNCERTAINTY         (1<<6)
+
+/**
+ * Flags to indicate what fields in GnssClock are valid.
+ */
+typedef uint16_t GnssClockFlags;
+/** A valid 'leap second' is stored in the data structure. */
+#define GNSS_CLOCK_HAS_LEAP_SECOND               (1<<0)
+/** A valid 'time uncertainty' is stored in the data structure. */
+#define GNSS_CLOCK_HAS_TIME_UNCERTAINTY          (1<<1)
+/** A valid 'full bias' is stored in the data structure. */
+#define GNSS_CLOCK_HAS_FULL_BIAS                 (1<<2)
+/** A valid 'bias' is stored in the data structure. */
+#define GNSS_CLOCK_HAS_BIAS                      (1<<3)
+/** A valid 'bias uncertainty' is stored in the data structure. */
+#define GNSS_CLOCK_HAS_BIAS_UNCERTAINTY          (1<<4)
+/** A valid 'drift' is stored in the data structure. */
+#define GNSS_CLOCK_HAS_DRIFT                     (1<<5)
+/** A valid 'drift uncertainty' is stored in the data structure. */
+#define GNSS_CLOCK_HAS_DRIFT_UNCERTAINTY         (1<<6)
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. */
+typedef uint8_t GpsClockType;
+#define GPS_CLOCK_TYPE_UNKNOWN                  0
+#define GPS_CLOCK_TYPE_LOCAL_HW_TIME            1
+#define GPS_CLOCK_TYPE_GPS_TIME                 2
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. */
+typedef uint32_t GpsMeasurementFlags;
+#define GPS_MEASUREMENT_HAS_SNR                               (1<<0)
+#define GPS_MEASUREMENT_HAS_ELEVATION                         (1<<1)
+#define GPS_MEASUREMENT_HAS_ELEVATION_UNCERTAINTY             (1<<2)
+#define GPS_MEASUREMENT_HAS_AZIMUTH                           (1<<3)
+#define GPS_MEASUREMENT_HAS_AZIMUTH_UNCERTAINTY               (1<<4)
+#define GPS_MEASUREMENT_HAS_PSEUDORANGE                       (1<<5)
+#define GPS_MEASUREMENT_HAS_PSEUDORANGE_UNCERTAINTY           (1<<6)
+#define GPS_MEASUREMENT_HAS_CODE_PHASE                        (1<<7)
+#define GPS_MEASUREMENT_HAS_CODE_PHASE_UNCERTAINTY            (1<<8)
+#define GPS_MEASUREMENT_HAS_CARRIER_FREQUENCY                 (1<<9)
+#define GPS_MEASUREMENT_HAS_CARRIER_CYCLES                    (1<<10)
+#define GPS_MEASUREMENT_HAS_CARRIER_PHASE                     (1<<11)
+#define GPS_MEASUREMENT_HAS_CARRIER_PHASE_UNCERTAINTY         (1<<12)
+#define GPS_MEASUREMENT_HAS_BIT_NUMBER                        (1<<13)
+#define GPS_MEASUREMENT_HAS_TIME_FROM_LAST_BIT                (1<<14)
+#define GPS_MEASUREMENT_HAS_DOPPLER_SHIFT                     (1<<15)
+#define GPS_MEASUREMENT_HAS_DOPPLER_SHIFT_UNCERTAINTY         (1<<16)
+#define GPS_MEASUREMENT_HAS_USED_IN_FIX                       (1<<17)
+#define GPS_MEASUREMENT_HAS_UNCORRECTED_PSEUDORANGE_RATE      (1<<18)
+
+/**
+ * Flags to indicate what fields in GnssMeasurement are valid.
+ */
+typedef uint32_t GnssMeasurementFlags;
+/** A valid 'snr' is stored in the data structure. */
+#define GNSS_MEASUREMENT_HAS_SNR                               (1<<0)
+/** A valid 'carrier frequency' is stored in the data structure. */
+#define GNSS_MEASUREMENT_HAS_CARRIER_FREQUENCY                 (1<<9)
+/** A valid 'carrier cycles' is stored in the data structure. */
+#define GNSS_MEASUREMENT_HAS_CARRIER_CYCLES                    (1<<10)
+/** A valid 'carrier phase' is stored in the data structure. */
+#define GNSS_MEASUREMENT_HAS_CARRIER_PHASE                     (1<<11)
+/** A valid 'carrier phase uncertainty' is stored in the data structure. */
+#define GNSS_MEASUREMENT_HAS_CARRIER_PHASE_UNCERTAINTY         (1<<12)
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. */
+typedef uint8_t GpsLossOfLock;
+#define GPS_LOSS_OF_LOCK_UNKNOWN                            0
+#define GPS_LOSS_OF_LOCK_OK                                 1
+#define GPS_LOSS_OF_LOCK_CYCLE_SLIP                         2
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. Use GnssMultipathIndicator instead.
+ */
+typedef uint8_t GpsMultipathIndicator;
+#define GPS_MULTIPATH_INDICATOR_UNKNOWN                 0
+#define GPS_MULTIPATH_INDICATOR_DETECTED                1
+#define GPS_MULTIPATH_INDICATOR_NOT_USED                2
+
+/**
+ * Enumeration of available values for the GNSS Measurement's multipath
+ * indicator.
+ */
+typedef uint8_t GnssMultipathIndicator;
+/** The indicator is not available or unknown. */
+#define GNSS_MULTIPATH_INDICATOR_UNKNOWN                 0
+/** The measurement is indicated to be affected by multipath. */
+#define GNSS_MULTIPATH_INDICATOR_PRESENT                 1
+/** The measurement is indicated to be not affected by multipath. */
+#define GNSS_MULTIPATH_INDICATOR_NOT_PRESENT             2
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. */
+typedef uint16_t GpsMeasurementState;
+#define GPS_MEASUREMENT_STATE_UNKNOWN                   0
+#define GPS_MEASUREMENT_STATE_CODE_LOCK             (1<<0)
+#define GPS_MEASUREMENT_STATE_BIT_SYNC              (1<<1)
+#define GPS_MEASUREMENT_STATE_SUBFRAME_SYNC         (1<<2)
+#define GPS_MEASUREMENT_STATE_TOW_DECODED           (1<<3)
+#define GPS_MEASUREMENT_STATE_MSEC_AMBIGUOUS        (1<<4)
+
+/**
+ * Flags indicating the GNSS measurement state.
+ *
+ * The expected behavior here is for GPS HAL to set all the flags that applies.
+ * For example, if the state for a satellite is only C/A code locked and bit
+ * synchronized, and there is still millisecond ambiguity, the state should be
+ * set as:
+ *
+ * GNSS_MEASUREMENT_STATE_CODE_LOCK | GNSS_MEASUREMENT_STATE_BIT_SYNC |
+ *         GNSS_MEASUREMENT_STATE_MSEC_AMBIGUOUS
+ *
+ * If GNSS is still searching for a satellite, the corresponding state should be
+ * set to GNSS_MEASUREMENT_STATE_UNKNOWN(0).
+ */
+typedef uint32_t GnssMeasurementState;
+#define GNSS_MEASUREMENT_STATE_UNKNOWN                   0
+#define GNSS_MEASUREMENT_STATE_CODE_LOCK             (1<<0)
+#define GNSS_MEASUREMENT_STATE_BIT_SYNC              (1<<1)
+#define GNSS_MEASUREMENT_STATE_SUBFRAME_SYNC         (1<<2)
+#define GNSS_MEASUREMENT_STATE_TOW_DECODED           (1<<3)
+#define GNSS_MEASUREMENT_STATE_MSEC_AMBIGUOUS        (1<<4)
+#define GNSS_MEASUREMENT_STATE_SYMBOL_SYNC           (1<<5)
+#define GNSS_MEASUREMENT_STATE_GLO_STRING_SYNC       (1<<6)
+#define GNSS_MEASUREMENT_STATE_GLO_TOD_DECODED       (1<<7)
+#define GNSS_MEASUREMENT_STATE_BDS_D2_BIT_SYNC       (1<<8)
+#define GNSS_MEASUREMENT_STATE_BDS_D2_SUBFRAME_SYNC  (1<<9)
+#define GNSS_MEASUREMENT_STATE_GAL_E1BC_CODE_LOCK    (1<<10)
+#define GNSS_MEASUREMENT_STATE_GAL_E1C_2ND_CODE_LOCK (1<<11)
+#define GNSS_MEASUREMENT_STATE_GAL_E1B_PAGE_SYNC     (1<<12)
+#define GNSS_MEASUREMENT_STATE_SBAS_SYNC             (1<<13)
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. */
+typedef uint16_t GpsAccumulatedDeltaRangeState;
+#define GPS_ADR_STATE_UNKNOWN                       0
+#define GPS_ADR_STATE_VALID                     (1<<0)
+#define GPS_ADR_STATE_RESET                     (1<<1)
+#define GPS_ADR_STATE_CYCLE_SLIP                (1<<2)
+
+/**
+ * Flags indicating the Accumulated Delta Range's states.
+ */
+typedef uint16_t GnssAccumulatedDeltaRangeState;
+#define GNSS_ADR_STATE_UNKNOWN                       0
+#define GNSS_ADR_STATE_VALID                     (1<<0)
+#define GNSS_ADR_STATE_RESET                     (1<<1)
+#define GNSS_ADR_STATE_CYCLE_SLIP                (1<<2)
+
+/* The following typedef together with its constants below are deprecated, and
+ * will be removed in the next release. */
+typedef uint8_t GpsNavigationMessageType;
+#define GPS_NAVIGATION_MESSAGE_TYPE_UNKNOWN         0
+#define GPS_NAVIGATION_MESSAGE_TYPE_L1CA            1
+#define GPS_NAVIGATION_MESSAGE_TYPE_L2CNAV          2
+#define GPS_NAVIGATION_MESSAGE_TYPE_L5CNAV          3
+#define GPS_NAVIGATION_MESSAGE_TYPE_CNAV2           4
+
+/**
+ * Enumeration of available values to indicate the GNSS Navigation message
+ * types.
+ *
+ * For convenience, first byte is the GnssConstellationType on which that signal
+ * is typically transmitted
+ */
+typedef int16_t GnssNavigationMessageType;
+
+#define GNSS_NAVIGATION_MESSAGE_TYPE_UNKNOWN       0
+/** GPS L1 C/A message contained in the structure.  */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L1CA      0x0101
+/** GPS L2-CNAV message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L2CNAV    0x0102
+/** GPS L5-CNAV message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L5CNAV    0x0103
+/** GPS CNAV-2 message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GPS_CNAV2     0x0104
+/** Glonass L1 CA message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GLO_L1CA      0x0301
+/** Beidou D1 message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_BDS_D1        0x0501
+/** Beidou D2 message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_BDS_D2        0x0502
+/** Galileo I/NAV message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GAL_I         0x0601
+/** Galileo F/NAV message contained in the structure. */
+#define GNSS_NAVIGATION_MESSAGE_TYPE_GAL_F         0x0602
+
+/**
+ * Status of Navigation Message
+ * When a message is received properly without any parity error in its navigation words, the
+ * status should be set to NAV_MESSAGE_STATUS_PARITY_PASSED. But if a message is received
+ * with words that failed parity check, but GPS is able to correct those words, the status
+ * should be set to NAV_MESSAGE_STATUS_PARITY_REBUILT.
+ * No need to send any navigation message that contains words with parity error and cannot be
+ * corrected.
+ */
+typedef uint16_t NavigationMessageStatus;
+#define NAV_MESSAGE_STATUS_UNKNOWN              0
+#define NAV_MESSAGE_STATUS_PARITY_PASSED   (1<<0)
+#define NAV_MESSAGE_STATUS_PARITY_REBUILT  (1<<1)
+
+/* This constant is deprecated, and will be removed in the next release. */
+#define NAV_MESSAGE_STATUS_UNKONW              0
+
+/**
+ * Flags that indicate information about the satellite
+ */
+typedef uint8_t                                 GnssSvFlags;
+#define GNSS_SV_FLAGS_NONE                      0
+#define GNSS_SV_FLAGS_HAS_EPHEMERIS_DATA        (1 << 0)
+#define GNSS_SV_FLAGS_HAS_ALMANAC_DATA          (1 << 1)
+#define GNSS_SV_FLAGS_USED_IN_FIX               (1 << 2)
+
+/**
+ * Constellation type of GnssSvInfo
+ */
+typedef uint8_t                         GnssConstellationType;
+#define GNSS_CONSTELLATION_UNKNOWN      0
+#define GNSS_CONSTELLATION_GPS          1
+#define GNSS_CONSTELLATION_SBAS         2
+#define GNSS_CONSTELLATION_GLONASS      3
+#define GNSS_CONSTELLATION_QZSS         4
+#define GNSS_CONSTELLATION_BEIDOU       5
+#define GNSS_CONSTELLATION_GALILEO      6
+
+/**
+ * Name for the GPS XTRA interface.
+ */
+#define GPS_XTRA_INTERFACE      "gps-xtra"
+
+/**
+ * Name for the GPS DEBUG interface.
+ */
+#define GPS_DEBUG_INTERFACE      "gps-debug"
+
+/**
+ * Name for the AGPS interface.
+ */
+#define AGPS_INTERFACE      "agps"
+
+/**
+ * Name of the Supl Certificate interface.
+ */
+#define SUPL_CERTIFICATE_INTERFACE  "supl-certificate"
+
+/**
+ * Name for NI interface
+ */
+#define GPS_NI_INTERFACE "gps-ni"
+
+/**
+ * Name for the AGPS-RIL interface.
+ */
+#define AGPS_RIL_INTERFACE      "agps_ril"
+
+/**
+ * Name for the GPS_Geofencing interface.
+ */
+#define GPS_GEOFENCING_INTERFACE   "gps_geofencing"
+
+/**
+ * Name of the GPS Measurements interface.
+ */
+#define GPS_MEASUREMENT_INTERFACE   "gps_measurement"
+
+/**
+ * Name of the GPS navigation message interface.
+ */
+#define GPS_NAVIGATION_MESSAGE_INTERFACE     "gps_navigation_message"
+
+/**
+ * Name of the GNSS/GPS configuration interface.
+ */
+#define GNSS_CONFIGURATION_INTERFACE     "gnss_configuration"
+
+/** Represents a location. */
+typedef struct {
+    /** set to sizeof(GpsLocation) */
+    size_t          size;
+    /** Contains GpsLocationFlags bits. */
+    uint16_t        flags;
+    /** Represents latitude in degrees. */
+    double          latitude;
+    /** Represents longitude in degrees. */
+    double          longitude;
+    /**
+     * Represents altitude in meters above the WGS 84 reference ellipsoid.
+     */
+    double          altitude;
+    /** Represents speed in meters per second. */
+    float           speed;
+    /** Represents heading in degrees. */
+    float           bearing;
+    /** Represents expected accuracy in meters. */
+    float           accuracy;
+    /** Timestamp for the location fix. */
+    GpsUtcTime      timestamp;
+} GpsLocation;
+
+/** Represents the status. */
+typedef struct {
+    /** set to sizeof(GpsStatus) */
+    size_t          size;
+    GpsStatusValue status;
+} GpsStatus;
+
+/**
+ * Legacy struct to represents SV information.
+ * Deprecated, to be removed in the next Android release.
+ * Use GnssSvInfo instead.
+ */
+typedef struct {
+    /** set to sizeof(GpsSvInfo) */
+    size_t          size;
+    /** Pseudo-random number for the SV. */
+    int     prn;
+    /** Signal to noise ratio. */
+    float   snr;
+    /** Elevation of SV in degrees. */
+    float   elevation;
+    /** Azimuth of SV in degrees. */
+    float   azimuth;
+} GpsSvInfo;
+
+typedef struct {
+    /** set to sizeof(GnssSvInfo) */
+    size_t size;
+
+    /**
+     * Pseudo-random number for the SV, or FCN/OSN number for Glonass. The
+     * distinction is made by looking at constellation field. Values should be
+     * in the range of:
+     *
+     * - GPS:     1-32
+     * - SBAS:    120-151, 183-192
+     * - GLONASS: 1-24, the orbital slot number (OSN), if known.  Or, if not:
+     *            93-106, the frequency channel number (FCN) (-7 to +6) offset by + 100
+     *            i.e. report an FCN of -7 as 93, FCN of 0 as 100, and FCN of +6 as 106.
+     * - QZSS:    193-200
+     * - Galileo: 1-36
+     * - Beidou:  1-37
+     */
+    int16_t svid;
+
+    /**
+     * Defines the constellation of the given SV. Value should be one of those
+     * GNSS_CONSTELLATION_* constants
+     */
+    GnssConstellationType constellation;
+
+    /**
+     * Carrier-to-noise density in dB-Hz, typically in the range [0, 63].
+     * It contains the measured C/N0 value for the signal at the antenna port.
+     *
+     * This is a mandatory value.
+     */
+    float c_n0_dbhz;
+
+    /** Elevation of SV in degrees. */
+    float elevation;
+
+    /** Azimuth of SV in degrees. */
+    float azimuth;
+
+    /**
+     * Contains additional data about the given SV. Value should be one of those
+     * GNSS_SV_FLAGS_* constants
+     */
+    GnssSvFlags flags;
+
+} GnssSvInfo;
+
+/**
+ * Legacy struct to represents SV status.
+ * Deprecated, to be removed in the next Android release.
+ * Use GnssSvStatus instead.
+ */
+typedef struct {
+    /** set to sizeof(GpsSvStatus) */
+    size_t size;
+    int num_svs;
+    GpsSvInfo sv_list[GPS_MAX_SVS];
+    uint32_t ephemeris_mask;
+    uint32_t almanac_mask;
+    uint32_t used_in_fix_mask;
+} GpsSvStatus;
+
+/**
+ * Represents SV status.
+ */
+typedef struct {
+    /** set to sizeof(GnssSvStatus) */
+    size_t size;
+
+    /** Number of GPS SVs currently visible, refers to the SVs stored in sv_list */
+    int num_svs;
+    /**
+     * Pointer to an array of SVs information for all GNSS constellations,
+     * except GPS, which is reported using sv_list
+     */
+    GnssSvInfo gnss_sv_list[GNSS_MAX_SVS];
+
+} GnssSvStatus;
+
+/* CellID for 2G, 3G and LTE, used in AGPS. */
+typedef struct {
+    AGpsRefLocationType type;
+    /** Mobile Country Code. */
+    uint16_t mcc;
+    /** Mobile Network Code .*/
+    uint16_t mnc;
+    /** Location Area Code in 2G, 3G and LTE. In 3G lac is discarded. In LTE,
+     * lac is populated with tac, to ensure that we don't break old clients that
+     * might rely in the old (wrong) behavior.
+     */
+    uint16_t lac;
+    /** Cell id in 2G. Utran Cell id in 3G. Cell Global Id EUTRA in LTE. */
+    uint32_t cid;
+    /** Tracking Area Code in LTE. */
+    uint16_t tac;
+    /** Physical Cell id in LTE (not used in 2G and 3G) */
+    uint16_t pcid;
+} AGpsRefLocationCellID;
+
+typedef struct {
+    uint8_t mac[6];
+} AGpsRefLocationMac;
+
+/** Represents ref locations */
+typedef struct {
+    AGpsRefLocationType type;
+    union {
+        AGpsRefLocationCellID   cellID;
+        AGpsRefLocationMac      mac;
+    } u;
+} AGpsRefLocation;
+
+/**
+ * Callback with location information. Can only be called from a thread created
+ * by create_thread_cb.
+ */
+typedef void (* gps_location_callback)(GpsLocation* location);
+
+/**
+ * Callback with status information. Can only be called from a thread created by
+ * create_thread_cb.
+ */
+typedef void (* gps_status_callback)(GpsStatus* status);
+
+/**
+ * Legacy callback with SV status information.
+ * Can only be called from a thread created by create_thread_cb.
+ *
+ * This callback is deprecated, and will be removed in the next release. Use
+ * gnss_sv_status_callback() instead.
+ */
+typedef void (* gps_sv_status_callback)(GpsSvStatus* sv_info);
+
+/**
+ * Callback with SV status information.
+ * Can only be called from a thread created by create_thread_cb.
+ */
+typedef void (* gnss_sv_status_callback)(GnssSvStatus* sv_info);
+
+/**
+ * Callback for reporting NMEA sentences. Can only be called from a thread
+ * created by create_thread_cb.
+ */
+typedef void (* gps_nmea_callback)(GpsUtcTime timestamp, const char* nmea, int length);
+
+/**
+ * Callback to inform framework of the GPS engine's capabilities. Capability
+ * parameter is a bit field of GPS_CAPABILITY_* flags.
+ */
+typedef void (* gps_set_capabilities)(uint32_t capabilities);
+
+/**
+ * Callback utility for acquiring the GPS wakelock. This can be used to prevent
+ * the CPU from suspending while handling GPS events.
+ */
+typedef void (* gps_acquire_wakelock)();
+
+/** Callback utility for releasing the GPS wakelock. */
+typedef void (* gps_release_wakelock)();
+
+/** Callback for requesting NTP time */
+typedef void (* gps_request_utc_time)();
+
+/**
+ * Callback for creating a thread that can call into the Java framework code.
+ * This must be used to create any threads that report events up to the
+ * framework.
+ */
+typedef pthread_t (* gps_create_thread)(const char* name, void (*start)(void *), void* arg);
+
+/**
+ * Provides information about how new the underlying GPS/GNSS hardware and
+ * software is.
+ *
+ * This information will be available for Android Test Applications. If a GPS
+ * HAL does not provide this information, it will be considered "2015 or
+ * earlier".
+ *
+ * If a GPS HAL does provide this information, then newer years will need to
+ * meet newer CTS standards. E.g. if the date are 2016 or above, then N+ level
+ * GpsMeasurement support will be verified.
+ */
+typedef struct {
+    /** Set to sizeof(GnssSystemInfo) */
+    size_t   size;
+    /* year in which the last update was made to the underlying hardware/firmware
+     * used to capture GNSS signals, e.g. 2016 */
+    uint16_t year_of_hw;
+} GnssSystemInfo;
+
+/**
+ * Callback to inform framework of the engine's hardware version information.
+ */
+typedef void (*gnss_set_system_info)(const GnssSystemInfo* info);
+
+/** New GPS callback structure. */
+typedef struct {
+    /** set to sizeof(GpsCallbacks) */
+    size_t      size;
+    gps_location_callback location_cb;
+    gps_status_callback status_cb;
+    gps_sv_status_callback sv_status_cb;
+    gps_nmea_callback nmea_cb;
+    gps_set_capabilities set_capabilities_cb;
+    gps_acquire_wakelock acquire_wakelock_cb;
+    gps_release_wakelock release_wakelock_cb;
+    gps_create_thread create_thread_cb;
+    gps_request_utc_time request_utc_time_cb;
+
+    gnss_set_system_info set_system_info_cb;
+    gnss_sv_status_callback gnss_sv_status_cb;
+} GpsCallbacks;
+
+/** Represents the standard GPS interface. */
+typedef struct {
+    /** set to sizeof(GpsInterface) */
+    size_t          size;
+    /**
+     * Opens the interface and provides the callback routines
+     * to the implementation of this interface.
+     */
+    int   (*init)( GpsCallbacks* callbacks );
+
+    /** Starts navigating. */
+    int   (*start)( void );
+
+    /** Stops navigating. */
+    int   (*stop)( void );
+
+    /** Closes the interface. */
+    void  (*cleanup)( void );
+
+    /** Injects the current time. */
+    int   (*inject_time)(GpsUtcTime time, int64_t timeReference,
+                         int uncertainty);
+
+    /**
+     * Injects current location from another location provider (typically cell
+     * ID). Latitude and longitude are measured in degrees expected accuracy is
+     * measured in meters
+     */
+    int  (*inject_location)(double latitude, double longitude, float accuracy);
+
+    /**
+     * Specifies that the next call to start will not use the
+     * information defined in the flags. GPS_DELETE_ALL is passed for
+     * a cold start.
+     */
+    void  (*delete_aiding_data)(GpsAidingData flags);
+
+    /**
+     * min_interval represents the time between fixes in milliseconds.
+     * preferred_accuracy represents the requested fix accuracy in meters.
+     * preferred_time represents the requested time to first fix in milliseconds.
+     *
+     * 'mode' parameter should be one of GPS_POSITION_MODE_MS_BASED
+     * or GPS_POSITION_MODE_STANDALONE.
+     * It is allowed by the platform (and it is recommended) to fallback to
+     * GPS_POSITION_MODE_MS_BASED if GPS_POSITION_MODE_MS_ASSISTED is passed in, and
+     * GPS_POSITION_MODE_MS_BASED is supported.
+     */
+    int   (*set_position_mode)(GpsPositionMode mode, GpsPositionRecurrence recurrence,
+            uint32_t min_interval, uint32_t preferred_accuracy, uint32_t preferred_time);
+
+    /** Get a pointer to extension information. */
+    const void* (*get_extension)(const char* name);
+} GpsInterface;
+
+/**
+ * Callback to request the client to download XTRA data. The client should
+ * download XTRA data and inject it by calling inject_xtra_data(). Can only be
+ * called from a thread created by create_thread_cb.
+ */
+typedef void (* gps_xtra_download_request)();
+
+/** Callback structure for the XTRA interface. */
+typedef struct {
+    gps_xtra_download_request download_request_cb;
+    gps_create_thread create_thread_cb;
+} GpsXtraCallbacks;
+
+/** Extended interface for XTRA support. */
+typedef struct {
+    /** set to sizeof(GpsXtraInterface) */
+    size_t          size;
+    /**
+     * Opens the XTRA interface and provides the callback routines
+     * to the implementation of this interface.
+     */
+    int  (*init)( GpsXtraCallbacks* callbacks );
+    /** Injects XTRA data into the GPS. */
+    int  (*inject_xtra_data)( char* data, int length );
+} GpsXtraInterface;
+
+/** Extended interface for DEBUG support. */
+typedef struct {
+    /** set to sizeof(GpsDebugInterface) */
+    size_t          size;
+
+    /**
+     * This function should return any information that the native
+     * implementation wishes to include in a bugreport.
+     */
+    size_t (*get_internal_state)(char* buffer, size_t bufferSize);
+} GpsDebugInterface;
+
+/*
+ * Represents the status of AGPS augmented to support IPv4 and IPv6.
+ */
+typedef struct {
+    /** set to sizeof(AGpsStatus) */
+    size_t                  size;
+
+    AGpsType                type;
+    AGpsStatusValue         status;
+
+    /**
+     * Must be set to a valid IPv4 address if the field 'addr' contains an IPv4
+     * address, or set to INADDR_NONE otherwise.
+     */
+    uint32_t                ipaddr;
+
+    /**
+     * Must contain the IPv4 (AF_INET) or IPv6 (AF_INET6) address to report.
+     * Any other value of addr.ss_family will be rejected.
+     */
+    struct sockaddr_storage addr;
+} AGpsStatus;
+
+/**
+ * Callback with AGPS status information. Can only be called from a thread
+ * created by create_thread_cb.
+ */
+typedef void (* agps_status_callback)(AGpsStatus* status);
+
+/** Callback structure for the AGPS interface. */
+typedef struct {
+    agps_status_callback status_cb;
+    gps_create_thread create_thread_cb;
+} AGpsCallbacks;
+
+/**
+ * Extended interface for AGPS support, it is augmented to enable to pass
+ * extra APN data.
+ */
+typedef struct {
+    /** set to sizeof(AGpsInterface) */
+    size_t size;
+
+    /**
+     * Opens the AGPS interface and provides the callback routines to the
+     * implementation of this interface.
+     */
+    void (*init)(AGpsCallbacks* callbacks);
+    /**
+     * Deprecated.
+     * If the HAL supports AGpsInterface_v2 this API will not be used, see
+     * data_conn_open_with_apn_ip_type for more information.
+     */
+    int (*data_conn_open)(const char* apn);
+    /**
+     * Notifies that the AGPS data connection has been closed.
+     */
+    int (*data_conn_closed)();
+    /**
+     * Notifies that a data connection is not available for AGPS.
+     */
+    int (*data_conn_failed)();
+    /**
+     * Sets the hostname and port for the AGPS server.
+     */
+    int (*set_server)(AGpsType type, const char* hostname, int port);
+
+    /**
+     * Notifies that a data connection is available and sets the name of the
+     * APN, and its IP type, to be used for SUPL connections.
+     */
+    int (*data_conn_open_with_apn_ip_type)(
+            const char* apn,
+            ApnIpType apnIpType);
+} AGpsInterface;
+
+/** Error codes associated with certificate operations */
+#define AGPS_CERTIFICATE_OPERATION_SUCCESS               0
+#define AGPS_CERTIFICATE_ERROR_GENERIC                -100
+#define AGPS_CERTIFICATE_ERROR_TOO_MANY_CERTIFICATES  -101
+
+/** A data structure that represents an X.509 certificate using DER encoding */
+typedef struct {
+    size_t  length;
+    u_char* data;
+} DerEncodedCertificate;
+
+/**
+ * A type definition for SHA1 Fingerprints used to identify X.509 Certificates
+ * The Fingerprint is a digest of the DER Certificate that uniquely identifies it.
+ */
+typedef struct {
+    u_char data[20];
+} Sha1CertificateFingerprint;
+
+/** AGPS Interface to handle SUPL certificate operations */
+typedef struct {
+    /** set to sizeof(SuplCertificateInterface) */
+    size_t size;
+
+    /**
+     * Installs a set of Certificates used for SUPL connections to the AGPS server.
+     * If needed the HAL should find out internally any certificates that need to be removed to
+     * accommodate the certificates to install.
+     * The certificates installed represent a full set of valid certificates needed to connect to
+     * AGPS SUPL servers.
+     * The list of certificates is required, and all must be available at the same time, when trying
+     * to establish a connection with the AGPS Server.
+     *
+     * Parameters:
+     *      certificates - A pointer to an array of DER encoded certificates that are need to be
+     *                     installed in the HAL.
+     *      length - The number of certificates to install.
+     * Returns:
+     *      AGPS_CERTIFICATE_OPERATION_SUCCESS if the operation is completed successfully
+     *      AGPS_CERTIFICATE_ERROR_TOO_MANY_CERTIFICATES if the HAL cannot store the number of
+     *          certificates attempted to be installed, the state of the certificates stored should
+     *          remain the same as before on this error case.
+     *
+     * IMPORTANT:
+     *      If needed the HAL should find out internally the set of certificates that need to be
+     *      removed to accommodate the certificates to install.
+     */
+    int  (*install_certificates) ( const DerEncodedCertificate* certificates, size_t length );
+
+    /**
+     * Notifies the HAL that a list of certificates used for SUPL connections are revoked. It is
+     * expected that the given set of certificates is removed from the internal store of the HAL.
+     *
+     * Parameters:
+     *      fingerprints - A pointer to an array of SHA1 Fingerprints to identify the set of
+     *                     certificates to revoke.
+     *      length - The number of fingerprints provided.
+     * Returns:
+     *      AGPS_CERTIFICATE_OPERATION_SUCCESS if the operation is completed successfully.
+     *
+     * IMPORTANT:
+     *      If any of the certificates provided (through its fingerprint) is not known by the HAL,
+     *      it should be ignored and continue revoking/deleting the rest of them.
+     */
+    int  (*revoke_certificates) ( const Sha1CertificateFingerprint* fingerprints, size_t length );
+} SuplCertificateInterface;
+
+/** Represents an NI request */
+typedef struct {
+    /** set to sizeof(GpsNiNotification) */
+    size_t          size;
+
+    /**
+     * An ID generated by HAL to associate NI notifications and UI
+     * responses
+     */
+    int             notification_id;
+
+    /**
+     * An NI type used to distinguish different categories of NI
+     * events, such as GPS_NI_TYPE_VOICE, GPS_NI_TYPE_UMTS_SUPL, ...
+     */
+    GpsNiType       ni_type;
+
+    /**
+     * Notification/verification options, combinations of GpsNiNotifyFlags constants
+     */
+    GpsNiNotifyFlags notify_flags;
+
+    /**
+     * Timeout period to wait for user response.
+     * Set to 0 for no time out limit.
+     */
+    int             timeout;
+
+    /**
+     * Default response when time out.
+     */
+    GpsUserResponseType default_response;
+
+    /**
+     * Requestor ID
+     */
+    char            requestor_id[GPS_NI_SHORT_STRING_MAXLEN];
+
+    /**
+     * Notification message. It can also be used to store client_id in some cases
+     */
+    char            text[GPS_NI_LONG_STRING_MAXLEN];
+
+    /**
+     * Client name decoding scheme
+     */
+    GpsNiEncodingType requestor_id_encoding;
+
+    /**
+     * Client name decoding scheme
+     */
+    GpsNiEncodingType text_encoding;
+
+    /**
+     * A pointer to extra data. Format:
+     * key_1 = value_1
+     * key_2 = value_2
+     */
+    char           extras[GPS_NI_LONG_STRING_MAXLEN];
+
+} GpsNiNotification;
+
+/**
+ * Callback with NI notification. Can only be called from a thread created by
+ * create_thread_cb.
+ */
+typedef void (*gps_ni_notify_callback)(GpsNiNotification *notification);
+
+/** GPS NI callback structure. */
+typedef struct
+{
+    /**
+     * Sends the notification request from HAL to GPSLocationProvider.
+     */
+    gps_ni_notify_callback notify_cb;
+    gps_create_thread create_thread_cb;
+} GpsNiCallbacks;
+
+/**
+ * Extended interface for Network-initiated (NI) support.
+ */
+typedef struct
+{
+    /** set to sizeof(GpsNiInterface) */
+    size_t          size;
+
+   /** Registers the callbacks for HAL to use. */
+   void (*init) (GpsNiCallbacks *callbacks);
+
+   /** Sends a response to HAL. */
+   void (*respond) (int notif_id, GpsUserResponseType user_response);
+} GpsNiInterface;
+
+#if defined(__ANDROID_OS__)
+struct gps_device_t {
+    struct hw_device_t common;
+
+    /**
+     * Set the provided lights to the provided values.
+     *
+     * Returns: 0 on succes, error code on failure.
+     */
+    const GpsInterface* (*get_gps_interface)(struct gps_device_t* dev);
+};
+#elif defined(__LINUX_OS__)
+struct gps_device_t {
+    const GpsInterface* (*get_gps_interface)(struct gps_device_t* dev);
+};
+#endif
+
+#define AGPS_RIL_REQUEST_REFLOC_CELLID  (1<<0L)
+#define AGPS_RIL_REQUEST_REFLOC_MAC     (1<<1L)
+
+typedef void (*agps_ril_request_set_id)(uint32_t flags);
+typedef void (*agps_ril_request_ref_loc)(uint32_t flags);
+
+typedef struct {
+    agps_ril_request_set_id request_setid;
+    agps_ril_request_ref_loc request_refloc;
+    gps_create_thread create_thread_cb;
+} AGpsRilCallbacks;
+
+/** Extended interface for AGPS_RIL support. */
+typedef struct {
+    /** set to sizeof(AGpsRilInterface) */
+    size_t          size;
+    /**
+     * Opens the AGPS interface and provides the callback routines
+     * to the implementation of this interface.
+     */
+    void  (*init)( AGpsRilCallbacks* callbacks );
+
+    /**
+     * Sets the reference location.
+     */
+    void (*set_ref_location) (const AGpsRefLocation *agps_reflocation, size_t sz_struct);
+    /**
+     * Sets the set ID.
+     */
+    void (*set_set_id) (AGpsSetIDType type, const char* setid);
+
+    /**
+     * Send network initiated message.
+     */
+    void (*ni_message) (uint8_t *msg, size_t len);
+
+    /**
+     * Notify GPS of network status changes.
+     * These parameters match values in the android.net.NetworkInfo class.
+     */
+    void (*update_network_state) (int connected, int type, int roaming, const char* extra_info);
+
+    /**
+     * Notify GPS of network status changes.
+     * These parameters match values in the android.net.NetworkInfo class.
+     */
+    void (*update_network_availability) (int avaiable, const char* apn);
+} AGpsRilInterface;
+
+/**
+ * GPS Geofence.
+ *      There are 3 states associated with a Geofence: Inside, Outside, Unknown.
+ * There are 3 transitions: ENTERED, EXITED, UNCERTAIN.
+ *
+ * An example state diagram with confidence level: 95% and Unknown time limit
+ * set as 30 secs is shown below. (confidence level and Unknown time limit are
+ * explained latter)
+ *                         ____________________________
+ *                        |       Unknown (30 secs)   |
+ *                         """"""""""""""""""""""""""""
+ *                            ^ |                  |  ^
+ *                   UNCERTAIN| |ENTERED     EXITED|  |UNCERTAIN
+ *                            | v                  v  |
+ *                        ________    EXITED     _________
+ *                       | Inside | -----------> | Outside |
+ *                       |        | <----------- |         |
+ *                        """"""""    ENTERED    """""""""
+ *
+ * Inside state: We are 95% confident that the user is inside the geofence.
+ * Outside state: We are 95% confident that the user is outside the geofence
+ * Unknown state: Rest of the time.
+ *
+ * The Unknown state is better explained with an example:
+ *
+ *                            __________
+ *                           |         c|
+ *                           |  ___     |    _______
+ *                           |  |a|     |   |   b   |
+ *                           |  """     |    """""""
+ *                           |          |
+ *                            """"""""""
+ * In the diagram above, "a" and "b" are 2 geofences and "c" is the accuracy
+ * circle reported by the GPS subsystem. Now with regard to "b", the system is
+ * confident that the user is outside. But with regard to "a" is not confident
+ * whether it is inside or outside the geofence. If the accuracy remains the
+ * same for a sufficient period of time, the UNCERTAIN transition would be
+ * triggered with the state set to Unknown. If the accuracy improves later, an
+ * appropriate transition should be triggered.  This "sufficient period of time"
+ * is defined by the parameter in the add_geofence_area API.
+ *     In other words, Unknown state can be interpreted as a state in which the
+ * GPS subsystem isn't confident enough that the user is either inside or
+ * outside the Geofence. It moves to Unknown state only after the expiry of the
+ * timeout.
+ *
+ * The geofence callback needs to be triggered for the ENTERED and EXITED
+ * transitions, when the GPS system is confident that the user has entered
+ * (Inside state) or exited (Outside state) the Geofence. An implementation
+ * which uses a value of 95% as the confidence is recommended. The callback
+ * should be triggered only for the transitions requested by the
+ * add_geofence_area call.
+ *
+ * Even though the diagram and explanation talks about states and transitions,
+ * the callee is only interested in the transistions. The states are mentioned
+ * here for illustrative purposes.
+ *
+ * Startup Scenario: When the device boots up, if an application adds geofences,
+ * and then we get an accurate GPS location fix, it needs to trigger the
+ * appropriate (ENTERED or EXITED) transition for every Geofence it knows about.
+ * By default, all the Geofences will be in the Unknown state.
+ *
+ * When the GPS system is unavailable, gps_geofence_status_callback should be
+ * called to inform the upper layers of the same. Similarly, when it becomes
+ * available the callback should be called. This is a global state while the
+ * UNKNOWN transition described above is per geofence.
+ *
+ * An important aspect to note is that users of this API (framework), will use
+ * other subsystems like wifi, sensors, cell to handle Unknown case and
+ * hopefully provide a definitive state transition to the third party
+ * application. GPS Geofence will just be a signal indicating what the GPS
+ * subsystem knows about the Geofence.
+ *
+ */
+#define GPS_GEOFENCE_ENTERED     (1<<0L)
+#define GPS_GEOFENCE_EXITED      (1<<1L)
+#define GPS_GEOFENCE_UNCERTAIN   (1<<2L)
+
+#define GPS_GEOFENCE_UNAVAILABLE (1<<0L)
+#define GPS_GEOFENCE_AVAILABLE   (1<<1L)
+
+#define GPS_GEOFENCE_OPERATION_SUCCESS           0
+#define GPS_GEOFENCE_ERROR_TOO_MANY_GEOFENCES -100
+#define GPS_GEOFENCE_ERROR_ID_EXISTS          -101
+#define GPS_GEOFENCE_ERROR_ID_UNKNOWN         -102
+#define GPS_GEOFENCE_ERROR_INVALID_TRANSITION -103
+#define GPS_GEOFENCE_ERROR_GENERIC            -149
+
+/**
+ * The callback associated with the geofence.
+ * Parameters:
+ *      geofence_id - The id associated with the add_geofence_area.
+ *      location    - The current GPS location.
+ *      transition  - Can be one of GPS_GEOFENCE_ENTERED, GPS_GEOFENCE_EXITED,
+ *                    GPS_GEOFENCE_UNCERTAIN.
+ *      timestamp   - Timestamp when the transition was detected.
+ *
+ * The callback should only be called when the caller is interested in that
+ * particular transition. For instance, if the caller is interested only in
+ * ENTERED transition, then the callback should NOT be called with the EXITED
+ * transition.
+ *
+ * IMPORTANT: If a transition is triggered resulting in this callback, the GPS
+ * subsystem will wake up the application processor, if its in suspend state.
+ */
+typedef void (*gps_geofence_transition_callback) (int32_t geofence_id,  GpsLocation* location,
+        int32_t transition, GpsUtcTime timestamp);
+
+/**
+ * The callback associated with the availability of the GPS system for geofencing
+ * monitoring. If the GPS system determines that it cannot monitor geofences
+ * because of lack of reliability or unavailability of the GPS signals, it will
+ * call this callback with GPS_GEOFENCE_UNAVAILABLE parameter.
+ *
+ * Parameters:
+ *  status - GPS_GEOFENCE_UNAVAILABLE or GPS_GEOFENCE_AVAILABLE.
+ *  last_location - Last known location.
+ */
+typedef void (*gps_geofence_status_callback) (int32_t status, GpsLocation* last_location);
+
+/**
+ * The callback associated with the add_geofence call.
+ *
+ * Parameter:
+ * geofence_id - Id of the geofence.
+ * status - GPS_GEOFENCE_OPERATION_SUCCESS
+ *          GPS_GEOFENCE_ERROR_TOO_MANY_GEOFENCES  - geofence limit has been reached.
+ *          GPS_GEOFENCE_ERROR_ID_EXISTS  - geofence with id already exists
+ *          GPS_GEOFENCE_ERROR_INVALID_TRANSITION - the monitorTransition contains an
+ *              invalid transition
+ *          GPS_GEOFENCE_ERROR_GENERIC - for other errors.
+ */
+typedef void (*gps_geofence_add_callback) (int32_t geofence_id, int32_t status);
+
+/**
+ * The callback associated with the remove_geofence call.
+ *
+ * Parameter:
+ * geofence_id - Id of the geofence.
+ * status - GPS_GEOFENCE_OPERATION_SUCCESS
+ *          GPS_GEOFENCE_ERROR_ID_UNKNOWN - for invalid id
+ *          GPS_GEOFENCE_ERROR_GENERIC for others.
+ */
+typedef void (*gps_geofence_remove_callback) (int32_t geofence_id, int32_t status);
+
+
+/**
+ * The callback associated with the pause_geofence call.
+ *
+ * Parameter:
+ * geofence_id - Id of the geofence.
+ * status - GPS_GEOFENCE_OPERATION_SUCCESS
+ *          GPS_GEOFENCE_ERROR_ID_UNKNOWN - for invalid id
+ *          GPS_GEOFENCE_ERROR_INVALID_TRANSITION -
+ *                    when monitor_transitions is invalid
+ *          GPS_GEOFENCE_ERROR_GENERIC for others.
+ */
+typedef void (*gps_geofence_pause_callback) (int32_t geofence_id, int32_t status);
+
+/**
+ * The callback associated with the resume_geofence call.
+ *
+ * Parameter:
+ * geofence_id - Id of the geofence.
+ * status - GPS_GEOFENCE_OPERATION_SUCCESS
+ *          GPS_GEOFENCE_ERROR_ID_UNKNOWN - for invalid id
+ *          GPS_GEOFENCE_ERROR_GENERIC for others.
+ */
+typedef void (*gps_geofence_resume_callback) (int32_t geofence_id, int32_t status);
+
+typedef struct {
+    gps_geofence_transition_callback geofence_transition_callback;
+    gps_geofence_status_callback geofence_status_callback;
+    gps_geofence_add_callback geofence_add_callback;
+    gps_geofence_remove_callback geofence_remove_callback;
+    gps_geofence_pause_callback geofence_pause_callback;
+    gps_geofence_resume_callback geofence_resume_callback;
+    gps_create_thread create_thread_cb;
+} GpsGeofenceCallbacks;
+
+/** Extended interface for GPS_Geofencing support */
+typedef struct {
+   /** set to sizeof(GpsGeofencingInterface) */
+   size_t          size;
+
+   /**
+    * Opens the geofence interface and provides the callback routines
+    * to the implementation of this interface.
+    */
+   void  (*init)( GpsGeofenceCallbacks* callbacks );
+
+   /**
+    * Add a geofence area. This api currently supports circular geofences.
+    * Parameters:
+    *    geofence_id - The id for the geofence. If a geofence with this id
+    *       already exists, an error value (GPS_GEOFENCE_ERROR_ID_EXISTS)
+    *       should be returned.
+    *    latitude, longtitude, radius_meters - The lat, long and radius
+    *       (in meters) for the geofence
+    *    last_transition - The current state of the geofence. For example, if
+    *       the system already knows that the user is inside the geofence,
+    *       this will be set to GPS_GEOFENCE_ENTERED. In most cases, it
+    *       will be GPS_GEOFENCE_UNCERTAIN.
+    *    monitor_transition - Which transitions to monitor. Bitwise OR of
+    *       GPS_GEOFENCE_ENTERED, GPS_GEOFENCE_EXITED and
+    *       GPS_GEOFENCE_UNCERTAIN.
+    *    notification_responsiveness_ms - Defines the best-effort description
+    *       of how soon should the callback be called when the transition
+    *       associated with the Geofence is triggered. For instance, if set
+    *       to 1000 millseconds with GPS_GEOFENCE_ENTERED, the callback
+    *       should be called 1000 milliseconds within entering the geofence.
+    *       This parameter is defined in milliseconds.
+    *       NOTE: This is not to be confused with the rate that the GPS is
+    *       polled at. It is acceptable to dynamically vary the rate of
+    *       sampling the GPS for power-saving reasons; thus the rate of
+    *       sampling may be faster or slower than this.
+    *    unknown_timer_ms - The time limit after which the UNCERTAIN transition
+    *       should be triggered. This parameter is defined in milliseconds.
+    *       See above for a detailed explanation.
+    */
+   void (*add_geofence_area) (int32_t geofence_id, double latitude, double longitude,
+       double radius_meters, int last_transition, int monitor_transitions,
+       int notification_responsiveness_ms, int unknown_timer_ms);
+
+   /**
+    * Pause monitoring a particular geofence.
+    * Parameters:
+    *   geofence_id - The id for the geofence.
+    */
+   void (*pause_geofence) (int32_t geofence_id);
+
+   /**
+    * Resume monitoring a particular geofence.
+    * Parameters:
+    *   geofence_id - The id for the geofence.
+    *   monitor_transitions - Which transitions to monitor. Bitwise OR of
+    *       GPS_GEOFENCE_ENTERED, GPS_GEOFENCE_EXITED and
+    *       GPS_GEOFENCE_UNCERTAIN.
+    *       This supersedes the value associated provided in the
+    *       add_geofence_area call.
+    */
+   void (*resume_geofence) (int32_t geofence_id, int monitor_transitions);
+
+   /**
+    * Remove a geofence area. After the function returns, no notifications
+    * should be sent.
+    * Parameter:
+    *   geofence_id - The id for the geofence.
+    */
+   void (*remove_geofence_area) (int32_t geofence_id);
+} GpsGeofencingInterface;
+
+/**
+ * Legacy struct to represent an estimate of the GPS clock time.
+ * Deprecated, to be removed in the next Android release.
+ * Use GnssClock instead.
+ */
+typedef struct {
+    /** set to sizeof(GpsClock) */
+    size_t size;
+    GpsClockFlags flags;
+    int16_t leap_second;
+    GpsClockType type;
+    int64_t time_ns;
+    double time_uncertainty_ns;
+    int64_t full_bias_ns;
+    double bias_ns;
+    double bias_uncertainty_ns;
+    double drift_nsps;
+    double drift_uncertainty_nsps;
+} GpsClock;
+
+/**
+ * Represents an estimate of the GPS clock time.
+ */
+typedef struct {
+    /** set to sizeof(GnssClock) */
+    size_t size;
+
+    /**
+     * A set of flags indicating the validity of the fields in this data
+     * structure.
+     */
+    GnssClockFlags flags;
+
+    /**
+     * Leap second data.
+     * The sign of the value is defined by the following equation:
+     *      utc_time_ns = time_ns - (full_bias_ns + bias_ns) - leap_second *
+     *      1,000,000,000
+     *
+     * If the data is available 'flags' must contain GNSS_CLOCK_HAS_LEAP_SECOND.
+     */
+    int16_t leap_second;
+
+    /**
+     * The GNSS receiver internal clock value. This is the local hardware clock
+     * value.
+     *
+     * For local hardware clock, this value is expected to be monotonically
+     * increasing while the hardware clock remains power on. (For the case of a
+     * HW clock that is not continuously on, see the
+     * hw_clock_discontinuity_count field). The receiver's estimate of GPS time
+     * can be derived by substracting the sum of full_bias_ns and bias_ns (when
+     * available) from this value.
+     *
+     * This GPS time is expected to be the best estimate of current GPS time
+     * that GNSS receiver can achieve.
+     *
+     * Sub-nanosecond accuracy can be provided by means of the 'bias_ns' field.
+     * The value contains the 'time uncertainty' in it.
+     *
+     * This field is mandatory.
+     */
+    int64_t time_ns;
+
+    /**
+     * 1-Sigma uncertainty associated with the clock's time in nanoseconds.
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * If the data is available, 'flags' must contain
+     * GNSS_CLOCK_HAS_TIME_UNCERTAINTY. This value is effectively zero (it is
+     * the reference local clock, by which all other times and time
+     * uncertainties are measured.)  (And thus this field can be not provided,
+     * per GNSS_CLOCK_HAS_TIME_UNCERTAINTY flag, or provided & set to 0.)
+     */
+    double time_uncertainty_ns;
+
+    /**
+     * The difference between hardware clock ('time' field) inside GPS receiver
+     * and the true GPS time since 0000Z, January 6, 1980, in nanoseconds.
+     *
+     * The sign of the value is defined by the following equation:
+     *      local estimate of GPS time = time_ns - (full_bias_ns + bias_ns)
+     *
+     * This value is mandatory if the receiver has estimated GPS time. If the
+     * computed time is for a non-GPS constellation, the time offset of that
+     * constellation to GPS has to be applied to fill this value. The error
+     * estimate for the sum of this and the bias_ns is the bias_uncertainty_ns,
+     * and the caller is responsible for using this uncertainty (it can be very
+     * large before the GPS time has been solved for.) If the data is available
+     * 'flags' must contain GNSS_CLOCK_HAS_FULL_BIAS.
+     */
+    int64_t full_bias_ns;
+
+    /**
+     * Sub-nanosecond bias.
+     * The error estimate for the sum of this and the full_bias_ns is the
+     * bias_uncertainty_ns
+     *
+     * If the data is available 'flags' must contain GNSS_CLOCK_HAS_BIAS. If GPS
+     * has computed a position fix. This value is mandatory if the receiver has
+     * estimated GPS time.
+     */
+    double bias_ns;
+
+    /**
+     * 1-Sigma uncertainty associated with the local estimate of GPS time (clock
+     * bias) in nanoseconds. The uncertainty is represented as an absolute
+     * (single sided) value.
+     *
+     * If the data is available 'flags' must contain
+     * GNSS_CLOCK_HAS_BIAS_UNCERTAINTY. This value is mandatory if the receiver
+     * has estimated GPS time.
+     */
+    double bias_uncertainty_ns;
+
+    /**
+     * The clock's drift in nanoseconds (per second).
+     *
+     * A positive value means that the frequency is higher than the nominal
+     * frequency, and that the (full_bias_ns + bias_ns) is growing more positive
+     * over time.
+     *
+     * The value contains the 'drift uncertainty' in it.
+     * If the data is available 'flags' must contain GNSS_CLOCK_HAS_DRIFT.
+     *
+     * This value is mandatory if the receiver has estimated GNSS time
+     */
+    double drift_nsps;
+
+    /**
+     * 1-Sigma uncertainty associated with the clock's drift in nanoseconds (per second).
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * If the data is available 'flags' must contain
+     * GNSS_CLOCK_HAS_DRIFT_UNCERTAINTY. If GPS has computed a position fix this
+     * field is mandatory and must be populated.
+     */
+    double drift_uncertainty_nsps;
+
+    /**
+     * When there are any discontinuities in the HW clock, this field is
+     * mandatory.
+     *
+     * A "discontinuity" is meant to cover the case of a switch from one source
+     * of clock to another.  A single free-running crystal oscillator (XO)
+     * should generally not have any discontinuities, and this can be set and
+     * left at 0.
+     *
+     * If, however, the time_ns value (HW clock) is derived from a composite of
+     * sources, that is not as smooth as a typical XO, or is otherwise stopped &
+     * restarted, then this value shall be incremented each time a discontinuity
+     * occurs.  (E.g. this value may start at zero at device boot-up and
+     * increment each time there is a change in clock continuity. In the
+     * unlikely event that this value reaches full scale, rollover (not
+     * clamping) is required, such that this value continues to change, during
+     * subsequent discontinuity events.)
+     *
+     * While this number stays the same, between GnssClock reports, it can be
+     * safely assumed that the time_ns value has been running continuously, e.g.
+     * derived from a single, high quality clock (XO like, or better, that's
+     * typically used during continuous GNSS signal sampling.)
+     *
+     * It is expected, esp. during periods where there are few GNSS signals
+     * available, that the HW clock be discontinuity-free as long as possible,
+     * as this avoids the need to use (waste) a GNSS measurement to fully
+     * re-solve for the GPS clock bias and drift, when using the accompanying
+     * measurements, from consecutive GnssData reports.
+     */
+    uint32_t hw_clock_discontinuity_count;
+
+} GnssClock;
+
+/**
+ * Legacy struct to represent a GPS Measurement, it contains raw and computed
+ * information.
+ * Deprecated, to be removed in the next Android release.
+ * Use GnssMeasurement instead.
+ */
+typedef struct {
+    /** set to sizeof(GpsMeasurement) */
+    size_t size;
+    GpsMeasurementFlags flags;
+    int8_t prn;
+    double time_offset_ns;
+    GpsMeasurementState state;
+    int64_t received_gps_tow_ns;
+    int64_t received_gps_tow_uncertainty_ns;
+    double c_n0_dbhz;
+    double pseudorange_rate_mps;
+    double pseudorange_rate_uncertainty_mps;
+    GpsAccumulatedDeltaRangeState accumulated_delta_range_state;
+    double accumulated_delta_range_m;
+    double accumulated_delta_range_uncertainty_m;
+    double pseudorange_m;
+    double pseudorange_uncertainty_m;
+    double code_phase_chips;
+    double code_phase_uncertainty_chips;
+    float carrier_frequency_hz;
+    int64_t carrier_cycles;
+    double carrier_phase;
+    double carrier_phase_uncertainty;
+    GpsLossOfLock loss_of_lock;
+    int32_t bit_number;
+    int16_t time_from_last_bit_ms;
+    double doppler_shift_hz;
+    double doppler_shift_uncertainty_hz;
+    GpsMultipathIndicator multipath_indicator;
+    double snr_db;
+    double elevation_deg;
+    double elevation_uncertainty_deg;
+    double azimuth_deg;
+    double azimuth_uncertainty_deg;
+    bool used_in_fix;
+} GpsMeasurement;
+
+/**
+ * Represents a GNSS Measurement, it contains raw and computed information.
+ *
+ * Independence - All signal measurement information (e.g. sv_time,
+ * pseudorange_rate, multipath_indicator) reported in this struct should be
+ * based on GNSS signal measurements only. You may not synthesize measurements
+ * by calculating or reporting expected measurements based on known or estimated
+ * position, velocity, or time.
+ */
+typedef struct {
+    /** set to sizeof(GpsMeasurement) */
+    size_t size;
+
+    /** A set of flags indicating the validity of the fields in this data structure. */
+    GnssMeasurementFlags flags;
+
+    /**
+     * Satellite vehicle ID number, as defined in GnssSvInfo::svid
+     * This is a mandatory value.
+     */
+    int16_t svid;
+
+    /**
+     * Defines the constellation of the given SV. Value should be one of those
+     * GNSS_CONSTELLATION_* constants
+     */
+    GnssConstellationType constellation;
+
+    /**
+     * Time offset at which the measurement was taken in nanoseconds.
+     * The reference receiver's time is specified by GpsData::clock::time_ns and should be
+     * interpreted in the same way as indicated by GpsClock::type.
+     *
+     * The sign of time_offset_ns is given by the following equation:
+     *      measurement time = GpsClock::time_ns + time_offset_ns
+     *
+     * It provides an individual time-stamp for the measurement, and allows sub-nanosecond accuracy.
+     * This is a mandatory value.
+     */
+    double time_offset_ns;
+
+    /**
+     * Per satellite sync state. It represents the current sync state for the associated satellite.
+     * Based on the sync state, the 'received GPS tow' field should be interpreted accordingly.
+     *
+     * This is a mandatory value.
+     */
+    GnssMeasurementState state;
+
+    /**
+     * The received GNSS Time-of-Week at the measurement time, in nanoseconds.
+     * Ensure that this field is independent (see comment at top of
+     * GnssMeasurement struct.)
+     *
+     * For GPS & QZSS, this is:
+     *   Received GPS Time-of-Week at the measurement time, in nanoseconds.
+     *   The value is relative to the beginning of the current GPS week.
+     *
+     *   Given the highest sync state that can be achieved, per each satellite, valid range
+     *   for this field can be:
+     *     Searching       : [ 0       ]   : GNSS_MEASUREMENT_STATE_UNKNOWN
+     *     C/A code lock   : [ 0   1ms ]   : GNSS_MEASUREMENT_STATE_CODE_LOCK is set
+     *     Bit sync        : [ 0  20ms ]   : GNSS_MEASUREMENT_STATE_BIT_SYNC is set
+     *     Subframe sync   : [ 0    6s ]   : GNSS_MEASUREMENT_STATE_SUBFRAME_SYNC is set
+     *     TOW decoded     : [ 0 1week ]   : GNSS_MEASUREMENT_STATE_TOW_DECODED is set
+     *
+     *   Note well: if there is any ambiguity in integer millisecond,
+     *   GNSS_MEASUREMENT_STATE_MSEC_AMBIGUOUS should be set accordingly, in the 'state' field.
+     *
+     *   This value must be populated if 'state' != GNSS_MEASUREMENT_STATE_UNKNOWN.
+     *
+     * For Glonass, this is:
+     *   Received Glonass time of day, at the measurement time in nanoseconds.
+     *
+     *   Given the highest sync state that can be achieved, per each satellite, valid range for
+     *   this field can be:
+     *     Searching       : [ 0       ]   : GNSS_MEASUREMENT_STATE_UNKNOWN
+     *     C/A code lock   : [ 0   1ms ]   : GNSS_MEASUREMENT_STATE_CODE_LOCK is set
+     *     Symbol sync     : [ 0  10ms ]   : GNSS_MEASUREMENT_STATE_SYMBOL_SYNC is set
+     *     Bit sync        : [ 0  20ms ]   : GNSS_MEASUREMENT_STATE_BIT_SYNC is set
+     *     String sync     : [ 0    2s ]   : GNSS_MEASUREMENT_STATE_GLO_STRING_SYNC is set
+     *     Time of day     : [ 0  1day ]   : GNSS_MEASUREMENT_STATE_GLO_TOD_DECODED is set
+     *
+     * For Beidou, this is:
+     *   Received Beidou time of week, at the measurement time in nanoseconds.
+     *
+     *   Given the highest sync state that can be achieved, per each satellite, valid range for
+     *   this field can be:
+     *     Searching    : [ 0       ] : GNSS_MEASUREMENT_STATE_UNKNOWN
+     *     C/A code lock: [ 0   1ms ] : GNSS_MEASUREMENT_STATE_CODE_LOCK is set
+     *     Bit sync (D2): [ 0   2ms ] : GNSS_MEASUREMENT_STATE_BDS_D2_BIT_SYNC is set
+     *     Bit sync (D1): [ 0  20ms ] : GNSS_MEASUREMENT_STATE_BIT_SYNC is set
+     *     Subframe (D2): [ 0  0.6s ] : GNSS_MEASUREMENT_STATE_BDS_D2_SUBFRAME_SYNC is set
+     *     Subframe (D1): [ 0    6s ] : GNSS_MEASUREMENT_STATE_SUBFRAME_SYNC is set
+     *     Time of week : [ 0 1week ] : GNSS_MEASUREMENT_STATE_TOW_DECODED is set
+     *
+     * For Galileo, this is:
+     *   Received Galileo time of week, at the measurement time in nanoseconds.
+     *
+     *     E1BC code lock   : [ 0   4ms ]   : GNSS_MEASUREMENT_STATE_GAL_E1BC_CODE_LOCK is set
+     *     E1C 2nd code lock: [ 0 100ms ]   :
+     *     GNSS_MEASUREMENT_STATE_GAL_E1C_2ND_CODE_LOCK is set
+     *
+     *     E1B page    : [ 0    2s ] : GNSS_MEASUREMENT_STATE_GAL_E1B_PAGE_SYNC is set
+     *     Time of week: [ 0 1week ] : GNSS_MEASUREMENT_STATE_TOW_DECODED is set
+     *
+     * For SBAS, this is:
+     *   Received SBAS time, at the measurement time in nanoseconds.
+     *
+     *   Given the highest sync state that can be achieved, per each satellite,
+     *   valid range for this field can be:
+     *     Searching    : [ 0     ] : GNSS_MEASUREMENT_STATE_UNKNOWN
+     *     C/A code lock: [ 0 1ms ] : GNSS_MEASUREMENT_STATE_CODE_LOCK is set
+     *     Symbol sync  : [ 0 2ms ] : GNSS_MEASUREMENT_STATE_SYMBOL_SYNC is set
+     *     Message      : [ 0  1s ] : GNSS_MEASUREMENT_STATE_SBAS_SYNC is set
+    */
+    int64_t received_sv_time_in_ns;
+
+    /**
+     * 1-Sigma uncertainty of the Received GPS Time-of-Week in nanoseconds.
+     *
+     * This value must be populated if 'state' != GPS_MEASUREMENT_STATE_UNKNOWN.
+     */
+    int64_t received_sv_time_uncertainty_in_ns;
+
+    /**
+     * Carrier-to-noise density in dB-Hz, typically in the range [0, 63].
+     * It contains the measured C/N0 value for the signal at the antenna port.
+     *
+     * This is a mandatory value.
+     */
+    double c_n0_dbhz;
+
+    /**
+     * Pseudorange rate at the timestamp in m/s. The correction of a given
+     * Pseudorange Rate value includes corrections for receiver and satellite
+     * clock frequency errors. Ensure that this field is independent (see
+     * comment at top of GnssMeasurement struct.)
+     *
+     * It is mandatory to provide the 'uncorrected' 'pseudorange rate', and provide GpsClock's
+     * 'drift' field as well (When providing the uncorrected pseudorange rate, do not apply the
+     * corrections described above.)
+     *
+     * The value includes the 'pseudorange rate uncertainty' in it.
+     * A positive 'uncorrected' value indicates that the SV is moving away from the receiver.
+     *
+     * The sign of the 'uncorrected' 'pseudorange rate' and its relation to the sign of 'doppler
+     * shift' is given by the equation:
+     *      pseudorange rate = -k * doppler shift   (where k is a constant)
+     *
+     * This should be the most accurate pseudorange rate available, based on
+     * fresh signal measurements from this channel.
+     *
+     * It is mandatory that this value be provided at typical carrier phase PRR
+     * quality (few cm/sec per second of uncertainty, or better) - when signals
+     * are sufficiently strong & stable, e.g. signals from a GPS simulator at >=
+     * 35 dB-Hz.
+     */
+    double pseudorange_rate_mps;
+
+    /**
+     * 1-Sigma uncertainty of the pseudorange_rate_mps.
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * This is a mandatory value.
+     */
+    double pseudorange_rate_uncertainty_mps;
+
+    /**
+     * Accumulated delta range's state. It indicates whether ADR is reset or there is a cycle slip
+     * (indicating loss of lock).
+     *
+     * This is a mandatory value.
+     */
+    GnssAccumulatedDeltaRangeState accumulated_delta_range_state;
+
+    /**
+     * Accumulated delta range since the last channel reset in meters.
+     * A positive value indicates that the SV is moving away from the receiver.
+     *
+     * The sign of the 'accumulated delta range' and its relation to the sign of 'carrier phase'
+     * is given by the equation:
+     *          accumulated delta range = -k * carrier phase    (where k is a constant)
+     *
+     * This value must be populated if 'accumulated delta range state' != GPS_ADR_STATE_UNKNOWN.
+     * However, it is expected that the data is only accurate when:
+     *      'accumulated delta range state' == GPS_ADR_STATE_VALID.
+     */
+    double accumulated_delta_range_m;
+
+    /**
+     * 1-Sigma uncertainty of the accumulated delta range in meters.
+     * This value must be populated if 'accumulated delta range state' != GPS_ADR_STATE_UNKNOWN.
+     */
+    double accumulated_delta_range_uncertainty_m;
+
+    /**
+     * Carrier frequency at which codes and messages are modulated, it can be L1 or L2.
+     * If the field is not set, the carrier frequency is assumed to be L1.
+     *
+     * If the data is available, 'flags' must contain
+     * GNSS_MEASUREMENT_HAS_CARRIER_FREQUENCY.
+     */
+    float carrier_frequency_hz;
+
+    /**
+     * The number of full carrier cycles between the satellite and the receiver.
+     * The reference frequency is given by the field 'carrier_frequency_hz'.
+     * Indications of possible cycle slips and resets in the accumulation of
+     * this value can be inferred from the accumulated_delta_range_state flags.
+     *
+     * If the data is available, 'flags' must contain
+     * GNSS_MEASUREMENT_HAS_CARRIER_CYCLES.
+     */
+    int64_t carrier_cycles;
+
+    /**
+     * The RF phase detected by the receiver, in the range [0.0, 1.0].
+     * This is usually the fractional part of the complete carrier phase measurement.
+     *
+     * The reference frequency is given by the field 'carrier_frequency_hz'.
+     * The value contains the 'carrier-phase uncertainty' in it.
+     *
+     * If the data is available, 'flags' must contain
+     * GNSS_MEASUREMENT_HAS_CARRIER_PHASE.
+     */
+    double carrier_phase;
+
+    /**
+     * 1-Sigma uncertainty of the carrier-phase.
+     * If the data is available, 'flags' must contain
+     * GNSS_MEASUREMENT_HAS_CARRIER_PHASE_UNCERTAINTY.
+     */
+    double carrier_phase_uncertainty;
+
+    /**
+     * An enumeration that indicates the 'multipath' state of the event.
+     *
+     * The multipath Indicator is intended to report the presence of overlapping
+     * signals that manifest as distorted correlation peaks.
+     *
+     * - if there is a distorted correlation peak shape, report that multipath
+     *   is GNSS_MULTIPATH_INDICATOR_PRESENT.
+     * - if there is not a distorted correlation peak shape, report
+     *   GNSS_MULTIPATH_INDICATOR_NOT_PRESENT
+     * - if signals are too weak to discern this information, report
+     *   GNSS_MULTIPATH_INDICATOR_UNKNOWN
+     *
+     * Example: when doing the standardized overlapping Multipath Performance
+     * test (3GPP TS 34.171) the Multipath indicator should report
+     * GNSS_MULTIPATH_INDICATOR_PRESENT for those signals that are tracked, and
+     * contain multipath, and GNSS_MULTIPATH_INDICATOR_NOT_PRESENT for those
+     * signals that are tracked and do not contain multipath.
+     */
+    GnssMultipathIndicator multipath_indicator;
+
+    /**
+     * Signal-to-noise ratio at correlator output in dB.
+     * If the data is available, 'flags' must contain GNSS_MEASUREMENT_HAS_SNR.
+     * This is the power ratio of the "correlation peak height above the
+     * observed noise floor" to "the noise RMS".
+     */
+    double snr_db;
+} GnssMeasurement;
+
+/**
+ * Legacy struct to represents a reading of GPS measurements.
+ * Deprecated, to be removed in the next Android release.
+ * Use GnssData instead.
+ */
+typedef struct {
+    /** set to sizeof(GpsData) */
+    size_t size;
+    size_t measurement_count;
+    GpsMeasurement measurements[GPS_MAX_MEASUREMENT];
+
+    /** The GPS clock time reading. */
+    GpsClock clock;
+} GpsData;
+
+/**
+ * Represents a reading of GNSS measurements. For devices where GnssSystemInfo's
+ * year_of_hw is set to 2016+, it is mandatory that these be provided, on
+ * request, when the GNSS receiver is searching/tracking signals.
+ *
+ * - Reporting of GPS constellation measurements is mandatory.
+ * - Reporting of all tracked constellations are encouraged.
+ */
+typedef struct {
+    /** set to sizeof(GnssData) */
+    size_t size;
+
+    /** Number of measurements. */
+    size_t measurement_count;
+
+    /** The array of measurements. */
+    GnssMeasurement measurements[GNSS_MAX_MEASUREMENT];
+
+    /** The GPS clock time reading. */
+    GnssClock clock;
+} GnssData;
+
+/**
+ * The legacy callback for to report measurements from the HAL.
+ *
+ * This callback is deprecated, and will be removed in the next release. Use
+ * gnss_measurement_callback() instead.
+ *
+ * Parameters:
+ *    data - A data structure containing the measurements.
+ */
+typedef void (*gps_measurement_callback) (GpsData* data);
+
+/**
+ * The callback for to report measurements from the HAL.
+ *
+ * Parameters:
+ *    data - A data structure containing the measurements.
+ */
+typedef void (*gnss_measurement_callback) (GnssData* data);
+
+typedef struct {
+    /** set to sizeof(GpsMeasurementCallbacks) */
+    size_t size;
+    gps_measurement_callback measurement_callback;
+    gnss_measurement_callback gnss_measurement_callback;
+} GpsMeasurementCallbacks;
+
+/**
+ * Extended interface for GPS Measurements support.
+ */
+typedef struct {
+    /** Set to sizeof(GpsMeasurementInterface) */
+    size_t size;
+
+    /**
+     * Initializes the interface and registers the callback routines with the HAL.
+     * After a successful call to 'init' the HAL must begin to provide updates at its own phase.
+     *
+     * Status:
+     *    GPS_MEASUREMENT_OPERATION_SUCCESS
+     *    GPS_MEASUREMENT_ERROR_ALREADY_INIT - if a callback has already been registered without a
+     *              corresponding call to 'close'
+     *    GPS_MEASUREMENT_ERROR_GENERIC - if any other error occurred, it is expected that the HAL
+     *              will not generate any updates upon returning this error code.
+     */
+    int (*init) (GpsMeasurementCallbacks* callbacks);
+
+    /**
+     * Stops updates from the HAL, and unregisters the callback routines.
+     * After a call to stop, the previously registered callbacks must be considered invalid by the
+     * HAL.
+     * If stop is invoked without a previous 'init', this function should perform no work.
+     */
+    void (*close) ();
+
+} GpsMeasurementInterface;
+
+/**
+ * Legacy struct to represents a GPS navigation message (or a fragment of it).
+ * Deprecated, to be removed in the next Android release.
+ * Use GnssNavigationMessage instead.
+ */
+typedef struct {
+    /** set to sizeof(GpsNavigationMessage) */
+    size_t size;
+    int8_t prn;
+    GpsNavigationMessageType type;
+    NavigationMessageStatus status;
+    int16_t message_id;
+    int16_t submessage_id;
+    size_t data_length;
+    uint8_t* data;
+} GpsNavigationMessage;
+
+/** Represents a GPS navigation message (or a fragment of it). */
+typedef struct {
+    /** set to sizeof(GnssNavigationMessage) */
+    size_t size;
+
+    /**
+     * Satellite vehicle ID number, as defined in GnssSvInfo::svid
+     * This is a mandatory value.
+     */
+    int16_t svid;
+
+    /**
+     * The type of message contained in the structure.
+     * This is a mandatory value.
+     */
+    GnssNavigationMessageType type;
+
+    /**
+     * The status of the received navigation message.
+     * No need to send any navigation message that contains words with parity error and cannot be
+     * corrected.
+     */
+    NavigationMessageStatus status;
+
+    /**
+     * Message identifier. It provides an index so the complete Navigation
+     * Message can be assembled.
+     *
+     * - For GPS L1 C/A subframe 4 and 5, this value corresponds to the 'frame
+     *   id' of the navigation message, in the range of 1-25 (Subframe 1, 2, 3
+     *   does not contain a 'frame id' and this value can be set to -1.)
+     *
+     * - For Glonass L1 C/A, this refers to the frame ID, in the range of 1-5.
+     *
+     * - For BeiDou D1, this refers to the frame number in the range of 1-24
+     *
+     * - For Beidou D2, this refers to the frame number, in the range of 1-120
+     *
+     * - For Galileo F/NAV nominal frame structure, this refers to the subframe
+     *   number, in the range of 1-12
+     *
+     * - For Galileo I/NAV nominal frame structure, this refers to the subframe
+     *   number in the range of 1-24
+     */
+    int16_t message_id;
+
+    /**
+     * Sub-message identifier. If required by the message 'type', this value
+     * contains a sub-index within the current message (or frame) that is being
+     * transmitted.
+     *
+     * - For GPS L1 C/A, BeiDou D1 & BeiDou D2, the submessage id corresponds to
+     *   the subframe number of the navigation message, in the range of 1-5.
+     *
+     * - For Glonass L1 C/A, this refers to the String number, in the range from
+     *   1-15
+     *
+     * - For Galileo F/NAV, this refers to the page type in the range 1-6
+     *
+     * - For Galileo I/NAV, this refers to the word type in the range 1-10+
+     */
+    int16_t submessage_id;
+
+    /**
+     * The length of the data (in bytes) contained in the current message.
+     * If this value is different from zero, 'data' must point to an array of the same size.
+     * e.g. for L1 C/A the size of the sub-frame will be 40 bytes (10 words, 30 bits/word).
+     *
+     * This is a mandatory value.
+     */
+    size_t data_length;
+
+    /**
+     * The data of the reported GPS message. The bytes (or words) specified
+     * using big endian format (MSB first).
+     *
+     * - For GPS L1 C/A, Beidou D1 & Beidou D2, each subframe contains 10 30-bit
+     *   words. Each word (30 bits) should be fit into the last 30 bits in a
+     *   4-byte word (skip B31 and B32), with MSB first, for a total of 40
+     *   bytes, covering a time period of 6, 6, and 0.6 seconds, respectively.
+     *
+     * - For Glonass L1 C/A, each string contains 85 data bits, including the
+     *   checksum.  These bits should be fit into 11 bytes, with MSB first (skip
+     *   B86-B88), covering a time period of 2 seconds.
+     *
+     * - For Galileo F/NAV, each word consists of 238-bit (sync & tail symbols
+     *   excluded). Each word should be fit into 30-bytes, with MSB first (skip
+     *   B239, B240), covering a time period of 10 seconds.
+     *
+     * - For Galileo I/NAV, each page contains 2 page parts, even and odd, with
+     *   a total of 2x114 = 228 bits, (sync & tail excluded) that should be fit
+     *   into 29 bytes, with MSB first (skip B229-B232).
+     */
+    uint8_t* data;
+
+} GnssNavigationMessage;
+
+/**
+ * The legacy callback to report an available fragment of a GPS navigation
+ * messages from the HAL.
+ *
+ * This callback is deprecated, and will be removed in the next release. Use
+ * gnss_navigation_message_callback() instead.
+ *
+ * Parameters:
+ *      message - The GPS navigation submessage/subframe representation.
+ */
+typedef void (*gps_navigation_message_callback) (GpsNavigationMessage* message);
+
+/**
+ * The callback to report an available fragment of a GPS navigation messages from the HAL.
+ *
+ * Parameters:
+ *      message - The GPS navigation submessage/subframe representation.
+ */
+typedef void (*gnss_navigation_message_callback) (GnssNavigationMessage* message);
+
+typedef struct {
+    /** set to sizeof(GpsNavigationMessageCallbacks) */
+    size_t size;
+    gps_navigation_message_callback navigation_message_callback;
+    gnss_navigation_message_callback gnss_navigation_message_callback;
+} GpsNavigationMessageCallbacks;
+
+/**
+ * Extended interface for GPS navigation message reporting support.
+ */
+typedef struct {
+    /** Set to sizeof(GpsNavigationMessageInterface) */
+    size_t size;
+
+    /**
+     * Initializes the interface and registers the callback routines with the HAL.
+     * After a successful call to 'init' the HAL must begin to provide updates as they become
+     * available.
+     *
+     * Status:
+     *      GPS_NAVIGATION_MESSAGE_OPERATION_SUCCESS
+     *      GPS_NAVIGATION_MESSAGE_ERROR_ALREADY_INIT - if a callback has already been registered
+     *              without a corresponding call to 'close'.
+     *      GPS_NAVIGATION_MESSAGE_ERROR_GENERIC - if any other error occurred, it is expected that
+     *              the HAL will not generate any updates upon returning this error code.
+     */
+    int (*init) (GpsNavigationMessageCallbacks* callbacks);
+
+    /**
+     * Stops updates from the HAL, and unregisters the callback routines.
+     * After a call to stop, the previously registered callbacks must be considered invalid by the
+     * HAL.
+     * If stop is invoked without a previous 'init', this function should perform no work.
+     */
+    void (*close) ();
+
+} GpsNavigationMessageInterface;
+
+/**
+ * Interface for passing GNSS configuration contents from platform to HAL.
+ */
+typedef struct {
+    /** Set to sizeof(GnssConfigurationInterface) */
+    size_t size;
+
+    /**
+     * Deliver GNSS configuration contents to HAL.
+     * Parameters:
+     *     config_data - a pointer to a char array which holds what usually is expected from
+                         file(/etc/gps.conf), i.e., a sequence of UTF8 strings separated by '\n'.
+     *     length - total number of UTF8 characters in configuraiton data.
+     *
+     * IMPORTANT:
+     *      GPS HAL should expect this function can be called multiple times. And it may be
+     *      called even when GpsLocationProvider is already constructed and enabled. GPS HAL
+     *      should maintain the existing requests for various callback regardless the change
+     *      in configuration data.
+     */
+    void (*configuration_update) (const char* config_data, int32_t length);
+} GnssConfigurationInterface;
+
+__END_DECLS
+
+#endif /* ANDROID_INCLUDE_HARDWARE_GPS_H */
+
diff --git a/src/connectivity/gps/gps_hal/inc/gps_internal.h b/src/connectivity/gps/gps_hal/inc/gps_internal.h
new file mode 100644
index 0000000..0aa335d
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/inc/gps_internal.h
@@ -0,0 +1,100 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_INCLUDE_HARDWARE_GPS_INTERNAL_H
+#define ANDROID_INCLUDE_HARDWARE_GPS_INTERNAL_H
+
+#ifdef __ANDROID_OS__
+#include "hardware/gps.h"
+#else
+#include "gps.h"
+#endif
+
+/****************************************************************************
+ * This file contains legacy structs that are deprecated/retired from gps.h *
+ ****************************************************************************/
+
+__BEGIN_DECLS
+
+/**
+ * Legacy GPS callback structure.
+ * Deprecated, to be removed in the next Android release.
+ * Use GpsCallbacks instead.
+ */
+typedef struct {
+    /** set to sizeof(GpsCallbacks_v1) */
+    size_t      size;
+    gps_location_callback location_cb;
+    gps_status_callback status_cb;
+    gps_sv_status_callback sv_status_cb;
+    gps_nmea_callback nmea_cb;
+    gps_set_capabilities set_capabilities_cb;
+    gps_acquire_wakelock acquire_wakelock_cb;
+    gps_release_wakelock release_wakelock_cb;
+    gps_create_thread create_thread_cb;
+    gps_request_utc_time request_utc_time_cb;
+} GpsCallbacks_v1;
+
+#pragma pack(push,4)
+// We need to keep the alignment of this data structure to 4-bytes, to ensure that in 64-bit
+// environments the size of this legacy definition does not collide with _v2. Implementations should
+// be using _v2 and _v3, so it's OK to pay the 'unaligned' penalty in 64-bit if an old
+// implementation is still in use.
+
+/**
+ * Legacy struct to represent the status of AGPS.
+ */
+typedef struct {
+    /** set to sizeof(AGpsStatus_v1) */
+    size_t          size;
+    AGpsType        type;
+    AGpsStatusValue status;
+} AGpsStatus_v1;
+
+#pragma pack(pop)
+
+/**
+ * Legacy struct to represent the status of AGPS augmented with a IPv4 address
+ * field.
+ */
+typedef struct {
+    /** set to sizeof(AGpsStatus_v2) */
+    size_t          size;
+    AGpsType        type;
+    AGpsStatusValue status;
+
+    /*-------------------- New fields in _v2 --------------------*/
+
+    uint32_t        ipaddr;
+} AGpsStatus_v2;
+
+/**
+ * Legacy extended interface for AGPS support.
+ * See AGpsInterface_v2 for more information.
+ */
+typedef struct {
+    /** set to sizeof(AGpsInterface_v1) */
+    size_t          size;
+    void  (*init)( AGpsCallbacks* callbacks );
+    int  (*data_conn_open)( const char* apn );
+    int  (*data_conn_closed)();
+    int  (*data_conn_failed)();
+    int  (*set_server)( AGpsType type, const char* hostname, int port );
+} AGpsInterface_v1;
+
+__END_DECLS
+
+#endif /* ANDROID_INCLUDE_HARDWARE_GPS_INTERNAL_H */
diff --git a/src/connectivity/gps/gps_hal/inc/gpshal.h b/src/connectivity/gps/gps_hal/inc/gpshal.h
new file mode 100644
index 0000000..0b0f9e2
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/inc/gpshal.h
@@ -0,0 +1,99 @@
+/* Copyright Statement:
+ *
+ * This software/firmware and related documentation ("MediaTek Software") are
+ * protected under relevant copyright laws. The information contained herein
+ * is confidential and proprietary to MediaTek Inc. and/or its licensors.
+ * Without the prior written permission of MediaTek inc. and/or its licensors,
+ * any reproduction, modification, use or disclosure of MediaTek Software,
+ * and information contained herein, in whole or in part, shall be strictly prohibited.
+ *
+ * MediaTek Inc. (C) 2016. All rights reserved.
+ *
+ * BY OPENING THIS FILE, RECEIVER HEREBY UNEQUIVOCALLY ACKNOWLEDGES AND AGREES
+ * THAT THE SOFTWARE/FIRMWARE AND ITS DOCUMENTATIONS ("MEDIATEK SOFTWARE")
+ * RECEIVED FROM MEDIATEK AND/OR ITS REPRESENTATIVES ARE PROVIDED TO RECEIVER ON
+ * AN "AS-IS" BASIS ONLY. MEDIATEK EXPRESSLY DISCLAIMS ANY AND ALL WARRANTIES,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NONINFRINGEMENT.
+ * NEITHER DOES MEDIATEK PROVIDE ANY WARRANTY WHATSOEVER WITH RESPECT TO THE
+ * SOFTWARE OF ANY THIRD PARTY WHICH MAY BE USED BY, INCORPORATED IN, OR
+ * SUPPLIED WITH THE MEDIATEK SOFTWARE, AND RECEIVER AGREES TO LOOK ONLY TO SUCH
+ * THIRD PARTY FOR ANY WARRANTY CLAIM RELATING THERETO. RECEIVER EXPRESSLY ACKNOWLEDGES
+ * THAT IT IS RECEIVER'S SOLE RESPONSIBILITY TO OBTAIN FROM ANY THIRD PARTY ALL PROPER LICENSES
+ * CONTAINED IN MEDIATEK SOFTWARE. MEDIATEK SHALL ALSO NOT BE RESPONSIBLE FOR ANY MEDIATEK
+ * SOFTWARE RELEASES MADE TO RECEIVER'S SPECIFICATION OR TO CONFORM TO A PARTICULAR
+ * STANDARD OR OPEN FORUM. RECEIVER'S SOLE AND EXCLUSIVE REMEDY AND MEDIATEK'S ENTIRE AND
+ * CUMULATIVE LIABILITY WITH RESPECT TO THE MEDIATEK SOFTWARE RELEASED HEREUNDER WILL BE,
+ * AT MEDIATEK'S OPTION, TO REVISE OR REPLACE THE MEDIATEK SOFTWARE AT ISSUE,
+ * OR REFUND ANY SOFTWARE LICENSE FEES OR SERVICE CHARGE PAID BY RECEIVER TO
+ * MEDIATEK FOR SUCH MEDIATEK SOFTWARE AT ISSUE.
+ *
+ * The following software/firmware and/or related documentation ("MediaTek Software")
+ * have been modified by MediaTek Inc. All revisions are subject to any receiver's
+ * applicable license agreements with MediaTek Inc.
+ */
+#ifndef __GPS_HAL_H__
+#define __GPS_HAL_H__
+
+#include "hardware/gps_mtk.h"
+#include <pthread.h>
+
+//=========================================================
+
+#define MAX_EPOLL_EVENT 50
+
+//=========================================================
+
+typedef enum {  // state order is important
+    GPSHAL_STATE_UNKNOWN,
+    GPSHAL_STATE_RESOURCE,
+    GPSHAL_STATE_CLEANUP,
+    GPSHAL_STATE_INIT,    // == STOP
+    GPSHAL_STATE_STOP,    // == INIT
+    GPSHAL_STATE_START
+} gpshal_state;
+
+typedef struct {
+    int       fd_mnl2hal;
+    int       fd_worker_epoll;
+    pthread_t thd_worker;
+
+    pthread_mutex_t mutex_gps_state_intent;
+    gpshal_state    gps_state_intent;  // what we want
+    gpshal_state    gps_state;  // what we are, but we may fail to change it
+
+    GpsCallbacks_ext* gps_cbs;
+    AGpsCallbacks*    agps_cbs;
+    GpsNiCallbacks*   gpsni_cbs;
+    AGpsRilCallbacks* agpsril_cbs;
+    GpsMeasurementCallbacks_ext*       meas_cbs;
+    GpsNavigationMessageCallbacks* navimsg_cbs;
+    GpsGeofenceCallbacks* geofence_cbs;
+    VzwDebugCallbacks* vzw_debug_cbs;
+} gpshal_context_t;
+
+//=========================================================
+
+extern gpshal_context_t g_gpshal_ctx;
+extern const AGpsInterface mtk_agps_inf;
+extern const GpsNiInterface  mtk_gps_ni_inf;
+extern const AGpsRilInterface mtk_agps_ril_inf;
+extern const GpsGeofencingInterface mtkGeofence_inf;
+
+
+//=========================================================
+
+extern const char* gpshal_state_to_string(gpshal_state state);
+
+extern int gpshal_gpscbs_save(GpsCallbacks_ext* src);
+
+extern void gpshal_set_gps_state_intent(gpshal_state newState);
+
+extern void gpshal2mnl_gps_init();
+extern void gpshal2mnl_gps_start();
+extern void gpshal2mnl_gps_stop();
+extern void gpshal2mnl_gps_cleanup();
+
+extern void gpshal_worker_thread(void *arg);
+
+#endif  //  __GPS_HAL_DEBUG_H__
diff --git a/src/connectivity/gps/gps_hal/inc/gpshal_param_check.h b/src/connectivity/gps/gps_hal/inc/gpshal_param_check.h
new file mode 100644
index 0000000..c87ec98
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/inc/gpshal_param_check.h
@@ -0,0 +1,91 @@
+/* Copyright Statement:
+ *
+ * This software/firmware and related documentation ("MediaTek Software") are
+ * protected under relevant copyright laws. The information contained herein
+ * is confidential and proprietary to MediaTek Inc. and/or its licensors.
+ * Without the prior written permission of MediaTek inc. and/or its licensors,
+ * any reproduction, modification, use or disclosure of MediaTek Software,
+ * and information contained herein, in whole or in part, shall be strictly prohibited.
+ *
+ * MediaTek Inc. (C) 2016. All rights reserved.
+ *
+ * BY OPENING THIS FILE, RECEIVER HEREBY UNEQUIVOCALLY ACKNOWLEDGES AND AGREES
+ * THAT THE SOFTWARE/FIRMWARE AND ITS DOCUMENTATIONS ("MEDIATEK SOFTWARE")
+ * RECEIVED FROM MEDIATEK AND/OR ITS REPRESENTATIVES ARE PROVIDED TO RECEIVER ON
+ * AN "AS-IS" BASIS ONLY. MEDIATEK EXPRESSLY DISCLAIMS ANY AND ALL WARRANTIES,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NONINFRINGEMENT.
+ * NEITHER DOES MEDIATEK PROVIDE ANY WARRANTY WHATSOEVER WITH RESPECT TO THE
+ * SOFTWARE OF ANY THIRD PARTY WHICH MAY BE USED BY, INCORPORATED IN, OR
+ * SUPPLIED WITH THE MEDIATEK SOFTWARE, AND RECEIVER AGREES TO LOOK ONLY TO SUCH
+ * THIRD PARTY FOR ANY WARRANTY CLAIM RELATING THERETO. RECEIVER EXPRESSLY ACKNOWLEDGES
+ * THAT IT IS RECEIVER'S SOLE RESPONSIBILITY TO OBTAIN FROM ANY THIRD PARTY ALL PROPER LICENSES
+ * CONTAINED IN MEDIATEK SOFTWARE. MEDIATEK SHALL ALSO NOT BE RESPONSIBLE FOR ANY MEDIATEK
+ * SOFTWARE RELEASES MADE TO RECEIVER'S SPECIFICATION OR TO CONFORM TO A PARTICULAR
+ * STANDARD OR OPEN FORUM. RECEIVER'S SOLE AND EXCLUSIVE REMEDY AND MEDIATEK'S ENTIRE AND
+ * CUMULATIVE LIABILITY WITH RESPECT TO THE MEDIATEK SOFTWARE RELEASED HEREUNDER WILL BE,
+ * AT MEDIATEK'S OPTION, TO REVISE OR REPLACE THE MEDIATEK SOFTWARE AT ISSUE,
+ * OR REFUND ANY SOFTWARE LICENSE FEES OR SERVICE CHARGE PAID BY RECEIVER TO
+ * MEDIATEK FOR SUCH MEDIATEK SOFTWARE AT ISSUE.
+ *
+ * The following software/firmware and/or related documentation ("MediaTek Software")
+ * have been modified by MediaTek Inc. All revisions are subject to any receiver's
+ * applicable license agreements with MediaTek Inc.
+ */
+
+#ifndef __GPS_HAL_PARAM_CHECK_H__
+#define __GPS_HAL_PARAM_CHECK_H__
+
+#include <string.h>
+
+#if 0 != PARAM_CHECK  // PARAM_CHECK is enabled
+    #define GPS_HW_MODULE_OPEN__CHECK_PARAM \
+        do { \
+            if (&HAL_MODULE_INFO_SYM != module) { \
+                ALOGT("-: Bad module object"); \
+                return -1;  /* Fail: any non-zero value */ \
+            } else if (NULL == id || strcmp(id, HAL_MODULE_INFO_SYM.id)) { \
+                ALOGT("-: Bad id"); \
+                return -2; \
+            } else if (NULL == device) { \
+                ALOGT("-: Bad device"); \
+                return -3; \
+            } \
+        } while (0)
+    #define GPS_DEVICE__GET_GPS_INTERFACE__CHECK_PARAM \
+        do { \
+            if (NULL == device || \
+                    &HAL_MODULE_INFO_SYM != device->common.module || \
+                gps_device__get_gps_interface != device->get_gps_interface) { \
+                ALOGT("-: Bad device object"); \
+                return NULL; \
+            } \
+        } while (0)
+#elif !defined(NDEBUG)  // assert() is effective
+    #define GPS_HW_MODULE_OPEN__CHECK_PARAM \
+        do { \
+            assert(&HAL_MODULE_INFO_SYM == module); \
+            assert(NULL != id); \
+            assert(NULL != device); \
+            assert(0 == strcmp(id, HAL_MODULE_INFO_SYM.id)); \
+        } while (0)
+    #define GPS_DEVICE__GET_GPS_INTERFACE__CHECK_PARAM \
+        do { \
+            assert(NULL != device); \
+            assert(&HAL_MODULE_INFO_SYM == device->common.module); \
+            assert(gps_device__get_gps_interface == device->get_gps_interface); \
+        } while (0)
+#else
+    // PARAM_CHECK is disabled
+    // And assert() is not effective
+    #define GPS_HW_MODULE_OPEN__CHECK_PARAM \
+        do { \
+            UNUSED(module); \
+            UNUSED(id); \
+        } while (0)
+    #define GPS_DEVICE__GET_GPS_INTERFACE__CHECK_PARAM \
+        UNUSED(device)
+#endif
+
+
+#endif  // __GPS_HAL_PARAM_CHECK_H__
\ No newline at end of file
diff --git a/src/connectivity/gps/gps_hal/inc/hal2mnl_interface.h b/src/connectivity/gps/gps_hal/inc/hal2mnl_interface.h
new file mode 100644
index 0000000..77cd331
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/inc/hal2mnl_interface.h
@@ -0,0 +1,87 @@
+#ifndef __HAL2MNL_INTERFACE_H__
+#define __HAL2MNL_INTERFACE_H__
+
+#include "hal_mnl_interface_common.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct {
+    void (*mnld_reboot)();
+
+    void (*location)(gps_location location);
+    void (*gps_status)(gps_status status);
+    void (*gps_sv)(gnss_sv_info sv);
+    void (*nmea)(int64_t timestamp, const char* nmea, int length);
+    void (*gps_capabilities)(gps_capabilites capabilities);
+    void (*gps_measurements)(gps_data data);
+    void (*gps_navigation)(gps_nav_msg msg);
+    void (*gnss_measurements)(gnss_data data);
+    void (*gnss_navigation)(gnss_nav_msg msg);
+
+    void (*request_wakelock)();
+    void (*release_wakelock)();
+
+    void (*request_utc_time)();
+
+    void (*request_data_conn)(struct sockaddr_storage* addr);
+    void (*release_data_conn)();
+    void (*request_ni_notify)(int session_id, agps_notify_type type, const char* requestor_id,
+        const char* client_name, ni_encoding_type requestor_id_encoding,
+        ni_encoding_type client_name_encoding);
+    void (*request_set_id)(request_setid flags);
+    void (*request_ref_loc)(request_refloc flags);
+    void (*output_vzw_debug)(const char* str);
+    void (*update_gnss_name)(const char* name, int length);
+    void (*request_nlp)(bool independentFromGnss);
+} mnl2hal_interface;
+
+int hal2mnl_hal_reboot();
+
+int hal2mnl_gps_init();
+int hal2mnl_gps_start();
+int hal2mnl_gps_stop();
+int hal2mnl_gps_cleanup();
+
+int hal2mnl_gps_inject_time(int64_t time, int64_t time_reference, int uncertainty);
+int hal2mnl_gps_inject_location(double lat, double lng, float acc);
+int hal2mnl_gps_delete_aiding_data(int flags);
+int hal2mnl_gps_set_position_mode(gps_pos_mode mode, gps_pos_recurrence recurrence,
+    int min_interval, int preferred_acc, int preferred_time, bool lowPowerMode);
+
+int hal2mnl_data_conn_open(const char* apn);
+int hal2mnl_data_conn_open_with_apn_ip_type(const char* apn, apn_ip_type ip_type);
+int hal2mnl_data_conn_closed();
+int hal2mnl_data_conn_failed();
+
+int hal2mnl_set_server(agps_type type, const char* hostname, int port);
+int hal2mnl_set_ref_location(cell_type type, int mcc, int mnc, int lac, int cid);
+int hal2mnl_set_id(agps_id_type type, const char* setid);
+
+int hal2mnl_ni_message(char* msg, int len);
+int hal2mnl_ni_respond(int notif_id, ni_user_response_type user_response);
+
+int hal2mnl_update_network_state(int connected, network_type type, int roaming,
+    const char* extra_info);
+int hal2mnl_update_network_availability(int available, const char* apn);
+
+int hal2mnl_set_gps_measurement(bool enabled, bool enableFullTracking);
+int hal2mnl_set_gps_navigation(bool enabled);
+
+int hal2mnl_set_vzw_debug(bool enabled);
+int hal2mnl_update_gnss_config(const char* config_data, int length);
+int hal2mnl_setBlacklist(long long* blacklist, int32_t size);
+
+// -1 means failure
+int mnl2hal_hdlr(int fd, mnl2hal_interface* hdlr);
+
+// -1 means failure
+int create_mnl2hal_fd();
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
diff --git a/src/connectivity/gps/gps_hal/inc/hal_mnl_interface_common.h b/src/connectivity/gps/gps_hal/inc/hal_mnl_interface_common.h
new file mode 100644
index 0000000..ab01a3a
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/inc/hal_mnl_interface_common.h
@@ -0,0 +1,1353 @@
+#ifndef __HAL_MNL_INTERFACE_COMMON_H__
+#define __HAL_MNL_INTERFACE_COMMON_H__
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <time.h>
+#include <sys/socket.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define HAL_MNL_BUFF_SIZE           (16 * 1024)
+#define HAL_MNL_INTERFACE_VERSION   1
+
+//======================================================
+// GPS HAL -> MNLD
+//======================================================
+#define MTK_HAL2MNL "mtk_hal2mnl"
+
+typedef enum {
+    HAL2MNL_HAL_REBOOT                      = 0,
+    HAL2MNL_GPS_INIT                        = 101,
+    HAL2MNL_GPS_START                       = 102,
+    HAL2MNL_GPS_STOP                        = 103,
+    HAL2MNL_GPS_CLEANUP                     = 104,
+    HAL2MNL_GPS_INJECT_TIME                 = 105,
+    HAL2MNL_GPS_INJECT_LOCATION             = 106,
+    HAL2MNL_GPS_DELETE_AIDING_DATA          = 107,
+    HAL2MNL_GPS_SET_POSITION_MODE           = 108,
+    HAL2MNL_DATA_CONN_OPEN                  = 201,
+    HAL2MNL_DATA_CONN_OPEN_WITH_APN_IP_TYPE = 202,
+    HAL2MNL_DATA_CONN_CLOSED                = 203,
+    HAL2MNL_DATA_CONN_FAILED                = 204,
+    HAL2MNL_SET_SERVER                      = 301,
+    HAL2MNL_SET_REF_LOCATION                = 302,
+    HAL2MNL_SET_ID                          = 303,
+    HAL2MNL_NI_MESSAGE                      = 401,
+    HAL2MNL_NI_RESPOND                      = 402,
+    HAL2MNL_UPDATE_NETWORK_STATE            = 501,
+    HAL2MNL_UPDATE_NETWORK_AVAILABILITY     = 502,
+    HAL2MNL_GPS_MEASUREMENT                 = 601,
+    HAL2MNL_GPS_NAVIGATION                  = 602,
+    HAL2MNL_VZW_DEBUG                       = 603,
+    HAL2MNL_GNSS_CONFIG                     = 604,
+    //HAL2MNL_SV_BLACKLIST                    = 605,
+    HAL2MNL_SEND_PMTK                       = 701,
+} hal2mnl_cmd;
+
+typedef int gps_pos_mode;
+#define GPS_POS_MODE_STANDALONE     0
+#define GPS_POS_MODE_MSB            1
+
+typedef int gps_pos_recurrence;
+#define GPS_POS_RECURRENCE_PERIODIC     0
+#define GPS_POS_RECURRENCE_SINGLE       1
+
+typedef int ni_user_response_type;
+#define NI_USER_RESPONSE_ACCEPT     1
+#define NI_USER_RESPONSE_DENY       2
+#define NI_USER_RESPONSE_NORESP     3
+
+typedef int cell_type;
+#define CELL_TYPE_GSM       1
+#define CELL_TYPE_UMTS      2
+
+typedef int agps_id_type;
+#define AGPS_ID_TYPE_NONE       0
+#define AGPS_ID_TYPE_IMSI       1
+#define AGPS_ID_TYPE_MSISDN     2
+
+typedef int network_type;
+#define NETWORK_TYPE_MOBILE         0
+#define NETWORK_TYPE_WIFI           1
+#define NETWORK_TYPE_MOBILE_MMS     2
+#define NETWORK_TYPE_MOBILE_SUPL    3
+#define NETWORK_TYPE_MOBILE_DUN     4
+#define NETWORK_TYPE_MOBILE_HIPRI   5
+#define NETWORK_TYPE_WIMAX          6
+
+typedef int apn_ip_type;
+#define MTK_APN_IP_INVALID          0
+#define MTK_APN_IP_IPV4             1
+#define MTK_APN_IP_IPV6             2
+#define MTK_APN_IP_IPV4V6           3
+
+typedef int agps_type;
+#define MTK_AGPS_TYPE_SUPL          1
+#define MTK_AGPS_TYPE_C2K           2
+
+//======================================================
+// MNLD -> GPS HAL
+//======================================================
+#define MTK_MNL2HAL "mtk_mnl2hal"
+
+typedef enum {
+    MNL2HAL_MNLD_REBOOT             = 1,
+    MNL2HAL_LOCATION                = 101,
+    MNL2HAL_GPS_STATUS              = 102,
+    MNL2HAL_GPS_SV                  = 103,
+    MNL2HAL_NMEA                    = 104,
+    MNL2HAL_GPS_CAPABILITIES        = 105,
+    MNL2HAL_GPS_MEASUREMENTS        = 106,
+    MNL2HAL_GPS_NAVIGATION          = 107,
+    MNL2HAL_GNSS_MEASUREMENTS       = 108,
+    MNL2HAL_GNSS_NAVIGATION         = 109,
+    MNL2HAL_REQUEST_WAKELOCK        = 201,
+    MNL2HAL_RELEASE_WAKELOCK        = 202,
+    MNL2HAL_REQUEST_UTC_TIME        = 301,
+    MNL2HAL_REQUEST_DATA_CONN       = 302,
+    MNL2HAL_RELEASE_DATA_CONN       = 303,
+    MNL2HAL_REQUEST_NI_NOTIFY       = 304,
+    MNL2HAL_REQUEST_SET_ID          = 305,
+    MNL2HAL_REQUEST_REF_LOC         = 306,
+    MNL2HAL_VZW_DEBUG_OUTPUT        = 307,
+    MNL2HAL_UPDATE_GNSS_NAME        = 308,
+    MNL2HAL_REQUEST_NLP             = 309,
+} mnl2hal_cmd;
+
+#define MTK_HAL_GNSS_MAX_SVS            64
+#define GPS_MAX_MEASUREMENT     32
+#define MTK_HAL_GNSS_MAX_MEASUREMENT    64
+
+typedef int gps_location_flags;
+#define MTK_GPS_LOCATION_HAS_LAT_LONG   0x0001
+#define MTK_GPS_LOCATION_HAS_ALT        0x0002
+#define MTK_GPS_LOCATION_HAS_SPEED      0x0004
+#define MTK_GPS_LOCATION_HAS_BEARING    0x0008
+#define MTK_GPS_LOCATION_HAS_HORIZONTAL_ACCURACY    0x0010
+#define MTK_GPS_LOCATION_HAS_VERTICAL_ACCURACY      0x0020
+#define MTK_GPS_LOCATION_HAS_SPEED_ACCURACY         0x0040
+#define MTK_GPS_LOCATION_HAS_BEARING_ACCURACY       0x0080
+
+typedef int gps_capabilites;
+#define GPS_CAP_NONE             0x0010000
+#define GPS_CAP_SCHEDULING       0x0000001
+#define GPS_CAP_MSB              0x0000002
+#define GPS_CAP_MSA              0x0000004
+#define GPS_CAP_SINGLE_SHOT      0x0000008
+#define GPS_CAP_ON_DEMAND_TIME   0x0000010
+#define GPS_CAP_GEOFENCING       0x0000020
+#define GPS_CAP_MEASUREMENTS     0x0000040
+#define GPS_CAP_NAV_MESSAGES     0x0000080
+
+typedef int request_setid;
+#define REQUEST_SETID_IMSI     (1<<0L)
+#define REQUEST_SETID_MSISDN   (1<<1L)
+
+typedef int request_refloc;
+#define REQUEST_REFLOC_CELLID  (1<<0L)
+#define REQUEST_REFLOC_MAC     (1<<1L)   // not ready
+
+typedef short gps_clock_flags;
+#define GPS_CLK_HAS_LEAP_SECOND               (1<<0)
+#define GPS_CLK_HAS_TIME_UNCERTAINTY          (1<<1)
+#define GPS_CLK_HAS_FULL_BIAS                 (1<<2)
+#define GPS_CLK_HAS_BIAS                      (1<<3)
+#define GPS_CLK_HAS_BIAS_UNCERTAINTY          (1<<4)
+#define GPS_CLK_HAS_DRIFT                     (1<<5)
+#define GPS_CLK_HAS_DRIFT_UNCERTAINTY         (1<<6)
+
+typedef char gps_clock_type;
+#define GPS_CLOCK_TYPE_UNKNOWN                  0
+#define GPS_CLOCK_TYPE_LOCAL_HW_TIME            1
+#define GPS_CLOCK_TYPE_GPS_TIME                 2
+
+typedef int gps_measurement_flags;
+#define GPS_MEASUREMENT_HAS_SNR                               (1<<0)
+#define GPS_MEASUREMENT_HAS_ELEVATION                         (1<<1)
+#define GPS_MEASUREMENT_HAS_ELEVATION_UNCERTAINTY             (1<<2)
+#define GPS_MEASUREMENT_HAS_AZIMUTH                           (1<<3)
+#define GPS_MEASUREMENT_HAS_AZIMUTH_UNCERTAINTY               (1<<4)
+#define GPS_MEASUREMENT_HAS_PSEUDORANGE                       (1<<5)
+#define GPS_MEASUREMENT_HAS_PSEUDORANGE_UNCERTAINTY           (1<<6)
+#define GPS_MEASUREMENT_HAS_CODE_PHASE                        (1<<7)
+#define GPS_MEASUREMENT_HAS_CODE_PHASE_UNCERTAINTY            (1<<8)
+#define GPS_MEASUREMENT_HAS_CARRIER_FREQUENCY                 (1<<9)
+#define GPS_MEASUREMENT_HAS_CARRIER_CYCLES                    (1<<10)
+#define GPS_MEASUREMENT_HAS_CARRIER_PHASE                     (1<<11)
+#define GPS_MEASUREMENT_HAS_CARRIER_PHASE_UNCERTAINTY         (1<<12)
+#define GPS_MEASUREMENT_HAS_BIT_NUMBER                        (1<<13)
+#define GPS_MEASUREMENT_HAS_TIME_FROM_LAST_BIT                (1<<14)
+#define GPS_MEASUREMENT_HAS_DOPPLER_SHIFT                     (1<<15)
+#define GPS_MEASUREMENT_HAS_DOPPLER_SHIFT_UNCERTAINTY         (1<<16)
+#define GPS_MEASUREMENT_HAS_USED_IN_FIX                       (1<<17)
+
+typedef short gps_measurement_state;
+#define GPS_MEASUREMENT_STATE_UNKNOWN                   0
+#define GPS_MEASUREMENT_STATE_CODE_LOCK             (1<<0)
+#define GPS_MEASUREMENT_STATE_BIT_SYNC              (1<<1)
+#define GPS_MEASUREMENT_STATE_SUBFRAME_SYNC         (1<<2)
+#define GPS_MEASUREMENT_STATE_TOW_DECODED           (1<<3)
+#define GPS_MEASUREMENT_STATE_MSEC_AMBIGUOUS        (1<<4)
+
+typedef short gps_accumulated_delta_range_state;
+#define GPS_ADR_STATE_UNKNOWN                       0
+#define GPS_ADR_STATE_VALID                     (1<<0)
+#define GPS_ADR_STATE_RESET                     (1<<1)
+#define GPS_ADR_STATE_CYCLE_SLIP                (1<<2)
+
+typedef char gps_loss_of_lock;
+#define GPS_LOSS_OF_LOCK_UNKNOWN                            0
+#define GPS_LOSS_OF_LOCK_OK                                 1
+#define GPS_LOSS_OF_LOCK_CYCLE_SLIP                         2
+
+typedef char gps_multipath_indicator;
+#define GPS_MULTIPATH_INDICATOR_UNKNOWN                 0
+#define GPS_MULTIPATH_INDICATOR_DETECTED                1
+#define GPS_MULTIPATH_INDICATOR_NOT_USED                2
+
+typedef char gps_nav_msg_type;
+#define GPS_NAV_MSG_TYPE_UNKNOWN         0
+#define GPS_NAV_MSG_TYPE_L1CA            1
+#define GPS_NAV_MSG_TYPE_L2CNAV          2
+#define GPS_NAV_MSG_TYPE_L5CNAV          3
+#define GPS_NAV_MSG_TYPE_CNAV2           4
+
+typedef short nav_msg_status;
+#define NAV_MSG_STATUS_UNKONW              0
+#define NAV_MSG_STATUS_PARITY_PASSED   (1<<0)
+#define NAV_MSG_STATUS_PARITY_REBUILT  (1<<1)
+
+typedef int gps_status;
+#define MTK_GPS_STATUS_SESSION_BEGIN        1
+#define MTK_GPS_STATUS_SESSION_END          2
+#define MTK_GPS_STATUS_SESSION_ENGINE_ON    3
+#define MTK_GPS_STATUS_SESSION_ENGINE_OFF   4
+
+typedef int agps_ni_type;
+#define AGPS_NI_TYPE_VOICE              1
+#define AGPS_NI_TYPE_UMTS_SUPL          2
+#define AGPS_NI_TYPE_UMTS_CTRL_PLANE    3
+#define AGPS_NI_TYPE_EMERGENCY_SUPL     4
+
+typedef int agps_notify_type;
+#define AGPS_NOTIFY_TYPE_NONE                       0
+#define AGPS_NOTIFY_TYPE_NOTIFY_ONLY                1
+#define AGPS_NOTIFY_TYPE_NOTIFY_ALLOW_NO_ANSWER     2
+#define AGPS_NOTIFY_TYPE_NOTIFY_DENY_NO_ANSWER      3
+#define AGPS_NOTIFY_TYPE_PRIVACY                    4
+
+typedef int ni_encoding_type;
+#define NI_ENCODING_TYPE_NONE   0
+#define NI_ENCODING_TYPE_GSM7   1
+#define NI_ENCODING_TYPE_UTF8   2
+#define NI_ENCODING_TYPE_UCS2   3
+
+typedef struct {
+    gps_location_flags flags;
+    double lat;
+    double lng;
+    double alt;
+    float speed;
+    float bearing;
+    float h_accuracy;  //horizontal
+    float v_accuracy;  //vertical
+    float s_accuracy;  //spedd
+    float b_accuracy;  //bearing
+    int64_t timestamp;
+} gps_location;
+
+typedef struct {
+    int16_t   svid;
+    uint8_t   constellation;
+    float     c_n0_dbhz;
+    float     elevation;
+    float     azimuth;
+    uint8_t   flags;
+    float     carrier_frequency;
+} gnss_sv;
+
+typedef struct {
+    int  num_svs;
+    gnss_sv  sv_list[MTK_HAL_GNSS_MAX_SVS];
+} gnss_sv_info;
+
+typedef struct {
+    int prn;
+    bool has_ephemeris_data;
+    bool has_almanac_data;
+    bool used_in_fix;
+} NmeaCash;
+
+typedef uint16_t MTK_HAL_NavigationMessageStatus;
+#define MTK_NAV_MESSAGE_STATUS_UNKNOWN              0
+#define MTK_NAV_MESSAGE_STATUS_PARITY_PASSED   (1<<0)
+#define MTK_NAV_MESSAGE_STATUS_PARITY_REBUILT  (1<<1)
+
+typedef int16_t MTK_HAL_GnssNavigationMessageType;
+#define MTK_GNSS_NAVIGATION_MESSAGE_TYPE_UNKNOWN       0
+/** GPS L1 C/A message contained in the structure.  */
+#define MTK_GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L1CA      0x0101
+/** GPS L2-CNAV message contained in the structure. */
+#define MTK_GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L2CNAV    0x0102
+/** GPS L5-CNAV message contained in the structure. */
+#define MTK_GNSS_NAVIGATION_MESSAGE_TYPE_GPS_L5CNAV    0x0103
+/** GPS CNAV-2 message contained in the structure. */
+#define MTK_GNSS_NAVIGATION_MESSAGE_TYPE_GPS_CNAV2     0x0104
+/** Glonass L1 CA message contained in the structure. */
+#define MTK_GNSS_NAVIGATION_MESSAGE_TYPE_GLO_L1CA      0x0301
+/** Beidou D1 message contained in the structure. */
+#define MTK_GNSS_NAVIGATION_MESSAGE_TYPE_BDS_D1        0x0501
+/** Beidou D2 message contained in the structure. */
+#define MTK_GNSS_NAVIGATION_MESSAGE_TYPE_BDS_D2        0x0502
+/** Galileo I/NAV message contained in the structure. */
+#define MTK_GNSS_NAVIGATION_MESSAGE_TYPE_GAL_I         0x0601
+/** Galileo F/NAV message contained in the structure. */
+#define MTK_GNSS_NAVIGATION_MESSAGE_TYPE_GAL_F         0x0602
+
+typedef uint8_t MTK_HAL_GnssMultipathIndicator;
+/** The indicator is not available or unknown. */
+#define MTK_GNSS_MULTIPATH_INDICATOR_UNKNOWN                 0
+/** The measurement is indicated to be affected by multipath. */
+#define MTK_GNSS_MULTIPATH_INDICATOR_PRESENT                 1
+/** The measurement is indicated to be not affected by multipath. */
+#define MTK_GNSS_MULTIPATH_INDICATOR_NOT_PRESENT             2
+
+typedef uint16_t MTK_HAL_GnssAccumulatedDeltaRangeState;
+#define MTK_GNSS_ADR_STATE_UNKNOWN                       0
+#define MTK_GNSS_ADR_STATE_VALID                     (1<<0)
+#define MTK_GNSS_ADR_STATE_RESET                     (1<<1)
+#define MTK_GNSS_ADR_STATE_CYCLE_SLIP                (1<<2)
+
+typedef uint32_t MTK_HAL_GnssMeasurementState;
+#define MTK_GNSS_MEASUREMENT_STATE_UNKNOWN                   0
+#define MTK_GNSS_MEASUREMENT_STATE_CODE_LOCK             (1<<0)
+#define MTK_GNSS_MEASUREMENT_STATE_BIT_SYNC              (1<<1)
+#define MTK_GNSS_MEASUREMENT_STATE_SUBFRAME_SYNC         (1<<2)
+#define MTK_GNSS_MEASUREMENT_STATE_TOW_DECODED           (1<<3)
+#define MTK_GNSS_MEASUREMENT_STATE_MSEC_AMBIGUOUS        (1<<4)
+#define MTK_GNSS_MEASUREMENT_STATE_SYMBOL_SYNC           (1<<5)
+#define MTK_GNSS_MEASUREMENT_STATE_GLO_STRING_SYNC       (1<<6)
+#define MTK_GNSS_MEASUREMENT_STATE_GLO_TOD_DECODED       (1<<7)
+#define MTK_GNSS_MEASUREMENT_STATE_BDS_D2_BIT_SYNC       (1<<8)
+#define MTK_GNSS_MEASUREMENT_STATE_BDS_D2_SUBFRAME_SYNC  (1<<9)
+#define MTK_GNSS_MEASUREMENT_STATE_GAL_E1BC_CODE_LOCK    (1<<10)
+#define MTK_GNSS_MEASUREMENT_STATE_GAL_E1C_2ND_CODE_LOCK (1<<11)
+#define MTK_GNSS_MEASUREMENT_STATE_GAL_E1B_PAGE_SYNC     (1<<12)
+#define MTK_GNSS_MEASUREMENT_STATE_SBAS_SYNC             (1<<13)
+
+typedef uint8_t  MTK_HAL_GnssConstellationType;
+#define MTK_GNSS_CONSTELLATION_UNKNOWN      0
+#define MTK_GNSS_CONSTELLATION_GPS          1
+#define MTK_GNSS_CONSTELLATION_SBAS         2
+#define MTK_GNSS_CONSTELLATION_GLONASS      3
+#define MTK_GNSS_CONSTELLATION_QZSS         4
+#define MTK_GNSS_CONSTELLATION_BEIDOU       5
+#define MTK_GNSS_CONSTELLATION_GALILEO      6
+
+typedef uint32_t MTK_HAL_GnssMeasurementFlags;
+/** A valid 'snr' is stored in the data structure. */
+#define MTK_GNSS_MEASUREMENT_HAS_SNR                               (1<<0)
+/** A valid 'carrier frequency' is stored in the data structure. */
+#define MTK_GNSS_MEASUREMENT_HAS_CARRIER_FREQUENCY                 (1<<9)
+/** A valid 'carrier cycles' is stored in the data structure. */
+#define MTK_GNSS_MEASUREMENT_HAS_CARRIER_CYCLES                    (1<<10)
+/** A valid 'carrier phase' is stored in the data structure. */
+#define MTK_GNSS_MEASUREMENT_HAS_CARRIER_PHASE                     (1<<11)
+/** A valid 'carrier phase uncertainty' is stored in the data structure. */
+#define MTK_GNSS_MEASUREMENT_HAS_CARRIER_PHASE_UNCERTAINTY         (1<<12)
+
+typedef uint16_t MTK_HAL_GnssClockFlags;
+/** A valid 'leap second' is stored in the data structure. */
+#define MTK_GNSS_CLOCK_HAS_LEAP_SECOND               (1<<0)
+/** A valid 'time uncertainty' is stored in the data structure. */
+#define MTK_GNSS_CLOCK_HAS_TIME_UNCERTAINTY          (1<<1)
+/** A valid 'full bias' is stored in the data structure. */
+#define MTK_GNSS_CLOCK_HAS_FULL_BIAS                 (1<<2)
+/** A valid 'bias' is stored in the data structure. */
+#define MTK_GNSS_CLOCK_HAS_BIAS                      (1<<3)
+/** A valid 'bias uncertainty' is stored in the data structure. */
+#define MTK_GNSS_CLOCK_HAS_BIAS_UNCERTAINTY          (1<<4)
+/** A valid 'drift' is stored in the data structure. */
+#define MTK_GNSS_CLOCK_HAS_DRIFT                     (1<<5)
+/** A valid 'drift uncertainty' is stored in the data structure. */
+#define MTK_GNSS_CLOCK_HAS_DRIFT_UNCERTAINTY         (1<<6)
+
+typedef struct {
+    /** A set of flags indicating the validity of the fields in this data structure. */
+    gps_clock_flags flags;
+
+    /**
+     * Leap second data.
+     * The sign of the value is defined by the following equation:
+     *      utc_time_ns = time_ns + (full_bias_ns + bias_ns) - leap_second * 1,000,000,000
+     *
+     * If the data is available 'flags' must contain GPS_CLOCK_HAS_LEAP_SECOND.
+     */
+    short leap_second;
+
+    /**
+     * Indicates the type of time reported by the 'time_ns' field.
+     */
+    gps_clock_type type;
+
+    /**
+     * The GPS receiver internal clock value. This can be either the local hardware clock value
+     * (GPS_CLOCK_TYPE_LOCAL_HW_TIME), or the current GPS time derived inside GPS receiver
+     * (GPS_CLOCK_TYPE_GPS_TIME). The field 'type' defines the time reported.
+     *
+     * For local hardware clock, this value is expected to be monotonically increasing during
+     * the reporting session. The real GPS time can be derived by compensating the 'full bias'
+     * (when it is available) from this value.
+     *
+     * For GPS time, this value is expected to be the best estimation of current GPS time that GPS
+     * receiver can achieve. Set the 'time uncertainty' appropriately when GPS time is specified.
+     *
+     * Sub-nanosecond accuracy can be provided by means of the 'bias' field.
+     * The value contains the 'time uncertainty' in it.
+     */
+    int64_t time_ns;
+
+    /**
+     * 1-Sigma uncertainty associated with the clock's time in nanoseconds.
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * This value should be set if GPS_CLOCK_TYPE_GPS_TIME is set.
+     * If the data is available 'flags' must contain GPS_CLOCK_HAS_TIME_UNCERTAINTY.
+     */
+    double time_uncertainty_ns;
+
+    /**
+     * The difference between hardware clock ('time' field) inside GPS receiver and the true GPS
+     * time since 0000Z, January 6, 1980, in nanoseconds.
+     * This value is used if and only if GPS_CLOCK_TYPE_LOCAL_HW_TIME is set, and GPS receiver
+     * has solved the clock for GPS time.
+     * The caller is responsible for using the 'bias uncertainty' field for quality check.
+     *
+     * The sign of the value is defined by the following equation:
+     *      true time (GPS time) = time_ns + (full_bias_ns + bias_ns)
+     *
+     * This value contains the 'bias uncertainty' in it.
+     * If the data is available 'flags' must contain GPS_CLOCK_HAS_FULL_BIAS.
+
+     */
+    int64_t full_bias_ns;
+
+    /**
+     * Sub-nanosecond bias.
+     * The value contains the 'bias uncertainty' in it.
+     *
+     * If the data is available 'flags' must contain GPS_CLOCK_HAS_BIAS.
+     */
+    double bias_ns;
+
+    /**
+     * 1-Sigma uncertainty associated with the clock's bias in nanoseconds.
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * If the data is available 'flags' must contain GPS_CLOCK_HAS_BIAS_UNCERTAINTY.
+     */
+    double bias_uncertainty_ns;
+
+    /**
+     * The clock's drift in nanoseconds (per second).
+     * A positive value means that the frequency is higher than the nominal frequency.
+     *
+     * The value contains the 'drift uncertainty' in it.
+     * If the data is available 'flags' must contain GPS_CLOCK_HAS_DRIFT.
+     *
+     * If GpsMeasurement's 'flags' field contains GPS_MEASUREMENT_HAS_UNCORRECTED_PSEUDORANGE_RATE,
+     * it is encouraged that this field is also provided.
+     */
+    double drift_nsps;
+
+    /**
+     * 1-Sigma uncertainty associated with the clock's drift in nanoseconds (per second).
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * If the data is available 'flags' must contain GPS_CLOCK_HAS_DRIFT_UNCERTAINTY.
+     */
+    double drift_uncertainty_nsps;
+} gps_clock;
+
+/**
+ * Represents an estimate of the GPS clock time.
+ */
+typedef struct {
+    /**
+     * A set of flags indicating the validity of the fields in this data
+     * structure.
+     */
+    MTK_HAL_GnssClockFlags flags;
+
+    /**
+     * Leap second data.
+     * The sign of the value is defined by the following equation:
+     *      utc_time_ns = time_ns - (full_bias_ns + bias_ns) - leap_second *
+     *      1,000,000,000
+     *
+     * If the data is available 'flags' must contain GNSS_CLOCK_HAS_LEAP_SECOND.
+     */
+    int16_t leap_second;
+
+    /**
+     * The GNSS receiver internal clock value. This is the local hardware clock
+     * value.
+     *
+     * For local hardware clock, this value is expected to be monotonically
+     * increasing while the hardware clock remains power on. (For the case of a
+     * HW clock that is not continuously on, see the
+     * hw_clock_discontinuity_count field). The receiver's estimate of GPS time
+     * can be derived by substracting the sum of full_bias_ns and bias_ns (when
+     * available) from this value.
+     *
+     * This GPS time is expected to be the best estimate of current GPS time
+     * that GNSS receiver can achieve.
+     *
+     * Sub-nanosecond accuracy can be provided by means of the 'bias_ns' field.
+     * The value contains the 'time uncertainty' in it.
+     *
+     * This field is mandatory.
+     */
+    int64_t time_ns;
+
+    /**
+     * 1-Sigma uncertainty associated with the clock's time in nanoseconds.
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * If the data is available, 'flags' must contain
+     * GNSS_CLOCK_HAS_TIME_UNCERTAINTY. This value is effectively zero (it is
+     * the reference local clock, by which all other times and time
+     * uncertainties are measured.)  (And thus this field can be not provided,
+     * per GNSS_CLOCK_HAS_TIME_UNCERTAINTY flag, or provided & set to 0.)
+     */
+    double time_uncertainty_ns;
+
+    /**
+     * The difference between hardware clock ('time' field) inside GPS receiver
+     * and the true GPS time since 0000Z, January 6, 1980, in nanoseconds.
+     *
+     * The sign of the value is defined by the following equation:
+     *      local estimate of GPS time = time_ns - (full_bias_ns + bias_ns)
+     *
+     * This value is mandatory if the receiver has estimated GPS time. If the
+     * computed time is for a non-GPS constellation, the time offset of that
+     * constellation to GPS has to be applied to fill this value. The error
+     * estimate for the sum of this and the bias_ns is the bias_uncertainty_ns,
+     * and the caller is responsible for using this uncertainty (it can be very
+     * large before the GPS time has been solved for.) If the data is available
+     * 'flags' must contain GNSS_CLOCK_HAS_FULL_BIAS.
+     */
+    int64_t full_bias_ns;
+
+    /**
+     * Sub-nanosecond bias.
+     * The error estimate for the sum of this and the full_bias_ns is the
+     * bias_uncertainty_ns
+     *
+     * If the data is available 'flags' must contain GNSS_CLOCK_HAS_BIAS. If GPS
+     * has computed a position fix. This value is mandatory if the receiver has
+     * estimated GPS time.
+     */
+    double bias_ns;
+
+    /**
+     * 1-Sigma uncertainty associated with the local estimate of GPS time (clock
+     * bias) in nanoseconds. The uncertainty is represented as an absolute
+     * (single sided) value.
+     *
+     * If the data is available 'flags' must contain
+     * GNSS_CLOCK_HAS_BIAS_UNCERTAINTY. This value is mandatory if the receiver
+     * has estimated GPS time.
+     */
+    double bias_uncertainty_ns;
+
+    /**
+     * The clock's drift in nanoseconds (per second).
+     *
+     * A positive value means that the frequency is higher than the nominal
+     * frequency, and that the (full_bias_ns + bias_ns) is growing more positive
+     * over time.
+     *
+     * The value contains the 'drift uncertainty' in it.
+     * If the data is available 'flags' must contain GNSS_CLOCK_HAS_DRIFT.
+     *
+     * This value is mandatory if the receiver has estimated GNSS time
+     */
+    double drift_nsps;
+
+    /**
+     * 1-Sigma uncertainty associated with the clock's drift in nanoseconds (per second).
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * If the data is available 'flags' must contain
+     * GNSS_CLOCK_HAS_DRIFT_UNCERTAINTY. If GPS has computed a position fix this
+     * field is mandatory and must be populated.
+     */
+    double drift_uncertainty_nsps;
+
+    /**
+     * When there are any discontinuities in the HW clock, this field is
+     * mandatory.
+     *
+     * A "discontinuity" is meant to cover the case of a switch from one source
+     * of clock to another.  A single free-running crystal oscillator (XO)
+     * should generally not have any discontinuities, and this can be set and
+     * left at 0.
+     *
+     * If, however, the time_ns value (HW clock) is derived from a composite of
+     * sources, that is not as smooth as a typical XO, or is otherwise stopped &
+     * restarted, then this value shall be incremented each time a discontinuity
+     * occurs.  (E.g. this value may start at zero at device boot-up and
+     * increment each time there is a change in clock continuity. In the
+     * unlikely event that this value reaches full scale, rollover (not
+     * clamping) is required, such that this value continues to change, during
+     * subsequent discontinuity events.)
+     *
+     * While this number stays the same, between GnssClock reports, it can be
+     * safely assumed that the time_ns value has been running continuously, e.g.
+     * derived from a single, high quality clock (XO like, or better, that's
+     * typically used during continuous GNSS signal sampling.)
+     *
+     * It is expected, esp. during periods where there are few GNSS signals
+     * available, that the HW clock be discontinuity-free as long as possible,
+     * as this avoids the need to use (waste) a GNSS measurement to fully
+     * re-solve for the GPS clock bias and drift, when using the accompanying
+     * measurements, from consecutive GnssData reports.
+     */
+    uint32_t hw_clock_discontinuity_count;
+} gnss_clock;
+
+typedef struct {
+    /** A set of flags indicating the validity of the fields in this data structure. */
+    gps_measurement_flags flags;
+
+    /**
+     * Pseudo-random number in the range of [1, 32]
+     * This is a Mandatory value.
+     */
+    int8_t prn;
+
+    /**
+     * Time offset at which the measurement was taken in nanoseconds.
+     * The reference receiver's time is specified by GpsData::clock::time_ns and should be
+     * interpreted in the same way as indicated by GpsClock::type.
+     *
+     * The sign of time_offset_ns is given by the following equation:
+     *      measurement time = GpsClock::time_ns + time_offset_ns
+     *
+     * It provides an individual time-stamp for the measurement, and allows sub-nanosecond accuracy.
+     * This is a Mandatory value.
+     */
+    double time_offset_ns;
+
+    /**
+     * Per satellite sync state. It represents the current sync state for the associated satellite.
+     * Based on the sync state, the 'received GPS tow' field should be interpreted accordingly.
+     * This is a Mandatory value.
+     */
+    gps_measurement_state state;
+
+    /**
+     * Received GPS Time-of-Week at the measurement time, in nanoseconds.
+     * The value is relative to the beginning of the current GPS week.
+     *
+     * Given the highest sync state that can be achieved, per each satellite, valid range for
+     * this field can be:
+     *     Searching       : [ 0       ]   : GPS_MEASUREMENT_STATE_UNKNOWN
+     *     C/A code lock   : [ 0   1ms ]   : GPS_MEASUREMENT_STATE_CODE_LOCK is set
+     *     Bit sync        : [ 0  20ms ]   : GPS_MEASUREMENT_STATE_BIT_SYNC is set
+     *     Subframe sync   : [ 0    6s ]   : GPS_MEASUREMENT_STATE_SUBFRAME_SYNC is set
+     *     TOW decoded     : [ 0 1week ]   : GPS_MEASUREMENT_STATE_TOW_DECODED is set
+     *
+     * However, if there is any ambiguity in integer millisecond,
+     * GPS_MEASUREMENT_STATE_MSEC_AMBIGUOUS should be set accordingly, in the 'state' field.
+     * This value must be populated if 'state' != GPS_MEASUREMENT_STATE_UNKNOWN.
+     */
+    int64_t received_gps_tow_ns;
+
+    /**
+     * 1-Sigma uncertainty of the Received GPS Time-of-Week in nanoseconds.
+     * This value must be populated if 'state' != GPS_MEASUREMENT_STATE_UNKNOWN.
+     */
+    int64_t received_gps_tow_uncertainty_ns;
+
+    /**
+     * Carrier-to-noise density in dB-Hz, in the range [0, 63].
+     * It contains the measured C/N0 value for the signal at the antenna input.
+     * This is a Mandatory value.
+     */
+    double c_n0_dbhz;
+
+    /**
+     * Pseudorange rate at the timestamp in m/s.
+     * The value also includes the effects of the receiver clock frequency and satellite clock
+     * frequency errors.
+     *
+     * The value includes the 'pseudorange rate uncertainty' in it.
+     * A positive value indicates that the pseudorange is getting larger.
+     * This is a Mandatory value.
+     */
+    double pseudorange_rate_mps;
+
+    /**
+     * 1-Sigma uncertainty of the pseudurange rate in m/s.
+     * The uncertainty is represented as an absolute (single sided) value.
+     * This is a Mandatory value.
+     */
+    double pseudorange_rate_uncertainty_mps;
+
+    /**
+     * Accumulated delta range's state. It indicates whether ADR is reset or there is a cycle slip
+     * (indicating loss of lock).
+     * This is a Mandatory value.
+     */
+    gps_accumulated_delta_range_state accumulated_delta_range_state;
+
+    /**
+     * Accumulated delta range since the last channel reset in meters.
+     * A positive value indicates that the SV is moving away from the receiver.
+     *
+     * The sign of the 'accumulated delta range' and its relation to the sign of 'carrier phase'
+     * is given by the equation:
+     *          accumulated delta range = -k * carrier phase    (where k is a constant)
+     *
+     * This value must be populated if 'accumulated delta range state' != GPS_ADR_STATE_UNKNOWN.
+     * However, it is expected that the data is only accurate when:
+     *      'accumulated delta range state' == GPS_ADR_STATE_VALID.
+     */
+    double accumulated_delta_range_m;
+
+    /**
+     * 1-Sigma uncertainty of the accumulated delta range in meters.
+     * The data is available if 'accumulated delta range state' != GPS_ADR_STATE_UNKNOWN.
+     */
+    double accumulated_delta_range_uncertainty_m;
+
+    /**
+     * Best derived Pseudorange by the chip-set, in meters.
+     * The value contains the 'pseudorange uncertainty' in it.
+     *
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_PSEUDORANGE.
+     */
+    double pseudorange_m;
+
+    /**
+     * 1-Sigma uncertainty of the pseudorange in meters.
+     * The value contains the 'pseudorange' and 'clock' uncertainty in it.
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_PSEUDORANGE_UNCERTAINTY.
+     */
+    double pseudorange_uncertainty_m;
+
+    /**
+     * A fraction of the current C/A code cycle, in the range [0.0, 1023.0]
+     * This value contains the time (in Chip units) since the last C/A code cycle (GPS Msec epoch).
+     *
+     * The reference frequency is given by the field 'carrier_frequency_hz'.
+     * The value contains the 'code-phase uncertainty' in it.
+     *
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_CODE_PHASE.
+     */
+    double code_phase_chips;
+
+    /**
+     * 1-Sigma uncertainty of the code-phase, in a fraction of chips.
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_CODE_PHASE_UNCERTAINTY.
+     */
+    double code_phase_uncertainty_chips;
+
+    /**
+     * Carrier frequency at which codes and messages are modulated, it can be L1 or L2.
+     * If the field is not set, the carrier frequency is assumed to be L1.
+     *
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_CARRIER_FREQUENCY.
+     */
+    float carrier_frequency_hz;
+
+    /**
+     * The number of full carrier cycles between the satellite and the receiver.
+     * The reference frequency is given by the field 'carrier_frequency_hz'.
+     *
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_CARRIER_CYCLES.
+     */
+    int64_t carrier_cycles;
+
+    /**
+     * The RF phase detected by the receiver, in the range [0.0, 1.0].
+     * This is usually the fractional part of the complete carrier phase measurement.
+     *
+     * The reference frequency is given by the field 'carrier_frequency_hz'.
+     * The value contains the 'carrier-phase uncertainty' in it.
+     *
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_CARRIER_PHASE.
+     */
+    double carrier_phase;
+
+    /**
+     * 1-Sigma uncertainty of the carrier-phase.
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_CARRIER_PHASE_UNCERTAINTY.
+     */
+    double carrier_phase_uncertainty;
+
+    /**
+     * An enumeration that indicates the 'loss of lock' state of the event.
+     */
+    gps_loss_of_lock loss_of_lock;
+
+    /**
+     * The number of GPS bits transmitted since Sat-Sun midnight (GPS week).
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_BIT_NUMBER.
+     */
+    int32_t bit_number;
+
+    /**
+     * The elapsed time since the last received bit in milliseconds, in the range [0, 20]
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_TIME_FROM_LAST_BIT.
+     */
+    int16_t time_from_last_bit_ms;
+
+    /**
+     * Doppler shift in Hz.
+     * A positive value indicates that the SV is moving toward the receiver.
+     *
+     * The reference frequency is given by the field 'carrier_frequency_hz'.
+     * The value contains the 'doppler shift uncertainty' in it.
+     *
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_DOPPLER_SHIFT.
+     */
+    double doppler_shift_hz;
+
+    /**
+     * 1-Sigma uncertainty of the doppler shift in Hz.
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_DOPPLER_SHIFT_UNCERTAINTY.
+     */
+    double doppler_shift_uncertainty_hz;
+
+    /**
+     * An enumeration that indicates the 'multipath' state of the event.
+     */
+    gps_multipath_indicator multipath_indicator;
+
+    /**
+     * Signal-to-noise ratio in dB.
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_SNR.
+     */
+    double snr_db;
+
+    /**
+     * Elevation in degrees, the valid range is [-90, 90].
+     * The value contains the 'elevation uncertainty' in it.
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_ELEVATION.
+     */
+    double elevation_deg;
+
+    /**
+     * 1-Sigma uncertainty of the elevation in degrees, the valid range is [0, 90].
+     * The uncertainty is represented as the absolute (single sided) value.
+     *
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_ELEVATION_UNCERTAINTY.
+     */
+    double elevation_uncertainty_deg;
+
+    /**
+     * Azimuth in degrees, in the range [0, 360).
+     * The value contains the 'azimuth uncertainty' in it.
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_AZIMUTH.
+     *  */
+    double azimuth_deg;
+
+    /**
+     * 1-Sigma uncertainty of the azimuth in degrees, the valid range is [0, 180].
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_AZIMUTH_UNCERTAINTY.
+     */
+    double azimuth_uncertainty_deg;
+
+    /**
+     * Whether the GPS represented by the measurement was used for computing the most recent fix.
+     * If the data is available, 'flags' must contain GPS_MEASUREMENT_HAS_USED_IN_FIX.
+     */
+    bool used_in_fix;
+} gps_measurement;
+
+/**
+ * Represents a GNSS Measurement, it contains raw and computed information.
+ *
+ * Independence - All signal measurement information (e.g. sv_time,
+ * pseudorange_rate, multipath_indicator) reported in this struct should be
+ * based on GNSS signal measurements only. You may not synthesize measurements
+ * by calculating or reporting expected measurements based on known or estimated
+ * position, velocity, or time.
+ */
+typedef struct {
+    /** A set of flags indicating the validity of the fields in this data structure. */
+    MTK_HAL_GnssMeasurementFlags flags;
+
+    /**
+     * Satellite vehicle ID number, as defined in GnssSvInfo::svid
+     * This is a mandatory value.
+     */
+    int16_t svid;
+
+    /**
+     * Defines the constellation of the given SV. Value should be one of those
+     * GNSS_CONSTELLATION_* constants
+     */
+    MTK_HAL_GnssConstellationType constellation;
+
+    /**
+     * Time offset at which the measurement was taken in nanoseconds.
+     * The reference receiver's time is specified by GpsData::clock::time_ns and should be
+     * interpreted in the same way as indicated by GpsClock::type.
+     *
+     * The sign of time_offset_ns is given by the following equation:
+     *      measurement time = GpsClock::time_ns + time_offset_ns
+     *
+     * It provides an individual time-stamp for the measurement, and allows sub-nanosecond accuracy.
+     * This is a mandatory value.
+     */
+    double time_offset_ns;
+
+    /**
+     * Per satellite sync state. It represents the current sync state for the associated satellite.
+     * Based on the sync state, the 'received GPS tow' field should be interpreted accordingly.
+     *
+     * This is a mandatory value.
+     */
+    MTK_HAL_GnssMeasurementState state;
+
+    /**
+     * The received GNSS Time-of-Week at the measurement time, in nanoseconds.
+     * Ensure that this field is independent (see comment at top of
+     * GnssMeasurement struct.)
+     *
+     * For GPS & QZSS, this is:
+     *   Received GPS Time-of-Week at the measurement time, in nanoseconds.
+     *   The value is relative to the beginning of the current GPS week.
+     *
+     *   Given the highest sync state that can be achieved, per each satellite, valid range
+     *   for this field can be:
+     *     Searching       : [ 0       ]   : GNSS_MEASUREMENT_STATE_UNKNOWN
+     *     C/A code lock   : [ 0   1ms ]   : GNSS_MEASUREMENT_STATE_CODE_LOCK is set
+     *     Bit sync        : [ 0  20ms ]   : GNSS_MEASUREMENT_STATE_BIT_SYNC is set
+     *     Subframe sync   : [ 0    6s ]   : GNSS_MEASUREMENT_STATE_SUBFRAME_SYNC is set
+     *     TOW decoded     : [ 0 1week ]   : GNSS_MEASUREMENT_STATE_TOW_DECODED is set
+     *
+     *   Note well: if there is any ambiguity in integer millisecond,
+     *   GNSS_MEASUREMENT_STATE_MSEC_AMBIGUOUS should be set accordingly, in the 'state' field.
+     *
+     *   This value must be populated if 'state' != GNSS_MEASUREMENT_STATE_UNKNOWN.
+     *
+     * For Glonass, this is:
+     *   Received Glonass time of day, at the measurement time in nanoseconds.
+     *
+     *   Given the highest sync state that can be achieved, per each satellite, valid range for
+     *   this field can be:
+     *     Searching       : [ 0       ]   : GNSS_MEASUREMENT_STATE_UNKNOWN
+     *     C/A code lock   : [ 0   1ms ]   : GNSS_MEASUREMENT_STATE_CODE_LOCK is set
+     *     Symbol sync     : [ 0  10ms ]   : GNSS_MEASUREMENT_STATE_SYMBOL_SYNC is set
+     *     Bit sync        : [ 0  20ms ]   : GNSS_MEASUREMENT_STATE_BIT_SYNC is set
+     *     String sync     : [ 0    2s ]   : GNSS_MEASUREMENT_STATE_GLO_STRING_SYNC is set
+     *     Time of day     : [ 0  1day ]   : GNSS_MEASUREMENT_STATE_GLO_TOD_DECODED is set
+     *
+     * For Beidou, this is:
+     *   Received Beidou time of week, at the measurement time in nanoseconds.
+     *
+     *   Given the highest sync state that can be achieved, per each satellite, valid range for
+     *   this field can be:
+     *     Searching    : [ 0       ] : GNSS_MEASUREMENT_STATE_UNKNOWN
+     *     C/A code lock: [ 0   1ms ] : GNSS_MEASUREMENT_STATE_CODE_LOCK is set
+     *     Bit sync (D2): [ 0   2ms ] : GNSS_MEASUREMENT_STATE_BDS_D2_BIT_SYNC is set
+     *     Bit sync (D1): [ 0  20ms ] : GNSS_MEASUREMENT_STATE_BIT_SYNC is set
+     *     Subframe (D2): [ 0  0.6s ] : GNSS_MEASUREMENT_STATE_BDS_D2_SUBFRAME_SYNC is set
+     *     Subframe (D1): [ 0    6s ] : GNSS_MEASUREMENT_STATE_SUBFRAME_SYNC is set
+     *     Time of week : [ 0 1week ] : GNSS_MEASUREMENT_STATE_TOW_DECODED is set
+     *
+     * For Galileo, this is:
+     *   Received Galileo time of week, at the measurement time in nanoseconds.
+     *
+     *     E1BC code lock   : [ 0   4ms ]   : GNSS_MEASUREMENT_STATE_GAL_E1BC_CODE_LOCK is set
+     *     E1C 2nd code lock: [ 0 100ms ]   :
+     *     GNSS_MEASUREMENT_STATE_GAL_E1C_2ND_CODE_LOCK is set
+     *
+     *     E1B page    : [ 0    2s ] : GNSS_MEASUREMENT_STATE_GAL_E1B_PAGE_SYNC is set
+     *     Time of week: [ 0 1week ] : GNSS_MEASUREMENT_STATE_TOW_DECODED is set
+     *
+     * For SBAS, this is:
+     *   Received SBAS time, at the measurement time in nanoseconds.
+     *
+     *   Given the highest sync state that can be achieved, per each satellite,
+     *   valid range for this field can be:
+     *     Searching    : [ 0     ] : GNSS_MEASUREMENT_STATE_UNKNOWN
+     *     C/A code lock: [ 0 1ms ] : GNSS_MEASUREMENT_STATE_CODE_LOCK is set
+     *     Symbol sync  : [ 0 2ms ] : GNSS_MEASUREMENT_STATE_SYMBOL_SYNC is set
+     *     Message      : [ 0  1s ] : GNSS_MEASUREMENT_STATE_SBAS_SYNC is set
+    */
+    int64_t received_sv_time_in_ns;
+
+    /**
+     * 1-Sigma uncertainty of the Received GPS Time-of-Week in nanoseconds.
+     *
+     * This value must be populated if 'state' != GPS_MEASUREMENT_STATE_UNKNOWN.
+     */
+    int64_t received_sv_time_uncertainty_in_ns;
+
+    /**
+     * Carrier-to-noise density in dB-Hz, typically in the range [0, 63].
+     * It contains the measured C/N0 value for the signal at the antenna port.
+     *
+     * This is a mandatory value.
+     */
+    double c_n0_dbhz;
+
+    /**
+     * Pseudorange rate at the timestamp in m/s. The correction of a given
+     * Pseudorange Rate value includes corrections for receiver and satellite
+     * clock frequency errors. Ensure that this field is independent (see
+     * comment at top of GnssMeasurement struct.)
+     *
+     * It is mandatory to provide the 'uncorrected' 'pseudorange rate', and provide GpsClock's
+     * 'drift' field as well (When providing the uncorrected pseudorange rate, do not apply the
+     * corrections described above.)
+     *
+     * The value includes the 'pseudorange rate uncertainty' in it.
+     * A positive 'uncorrected' value indicates that the SV is moving away from the receiver.
+     *
+     * The sign of the 'uncorrected' 'pseudorange rate' and its relation to the sign of 'doppler
+     * shift' is given by the equation:
+     *      pseudorange rate = -k * doppler shift   (where k is a constant)
+     *
+     * This should be the most accurate pseudorange rate available, based on
+     * fresh signal measurements from this channel.
+     *
+     * It is mandatory that this value be provided at typical carrier phase PRR
+     * quality (few cm/sec per second of uncertainty, or better) - when signals
+     * are sufficiently strong & stable, e.g. signals from a GPS simulator at >=
+     * 35 dB-Hz.
+     */
+    double pseudorange_rate_mps;
+
+    /**
+     * 1-Sigma uncertainty of the pseudorange_rate_mps.
+     * The uncertainty is represented as an absolute (single sided) value.
+     *
+     * This is a mandatory value.
+     */
+    double pseudorange_rate_uncertainty_mps;
+
+    /**
+     * Accumulated delta range's state. It indicates whether ADR is reset or there is a cycle slip
+     * (indicating loss of lock).
+     *
+     * This is a mandatory value.
+     */
+    MTK_HAL_GnssAccumulatedDeltaRangeState accumulated_delta_range_state;
+
+    /**
+     * Accumulated delta range since the last channel reset in meters.
+     * A positive value indicates that the SV is moving away from the receiver.
+     *
+     * The sign of the 'accumulated delta range' and its relation to the sign of 'carrier phase'
+     * is given by the equation:
+     *          accumulated delta range = -k * carrier phase    (where k is a constant)
+     *
+     * This value must be populated if 'accumulated delta range state' != GPS_ADR_STATE_UNKNOWN.
+     * However, it is expected that the data is only accurate when:
+     *      'accumulated delta range state' == GPS_ADR_STATE_VALID.
+     */
+    double accumulated_delta_range_m;
+
+    /**
+     * 1-Sigma uncertainty of the accumulated delta range in meters.
+     * This value must be populated if 'accumulated delta range state' != GPS_ADR_STATE_UNKNOWN.
+     */
+    double accumulated_delta_range_uncertainty_m;
+
+    /**
+     * Carrier frequency at which codes and messages are modulated, it can be L1 or L2.
+     * If the field is not set, the carrier frequency is assumed to be L1.
+     *
+     * If the data is available, 'flags' must contain
+     * GNSS_MEASUREMENT_HAS_CARRIER_FREQUENCY.
+     */
+    float carrier_frequency_hz;
+
+    /**
+     * The number of full carrier cycles between the satellite and the receiver.
+     * The reference frequency is given by the field 'carrier_frequency_hz'.
+     * Indications of possible cycle slips and resets in the accumulation of
+     * this value can be inferred from the accumulated_delta_range_state flags.
+     *
+     * If the data is available, 'flags' must contain
+     * GNSS_MEASUREMENT_HAS_CARRIER_CYCLES.
+     */
+    int64_t carrier_cycles;
+
+    /**
+     * The RF phase detected by the receiver, in the range [0.0, 1.0].
+     * This is usually the fractional part of the complete carrier phase measurement.
+     *
+     * The reference frequency is given by the field 'carrier_frequency_hz'.
+     * The value contains the 'carrier-phase uncertainty' in it.
+     *
+     * If the data is available, 'flags' must contain
+     * GNSS_MEASUREMENT_HAS_CARRIER_PHASE.
+     */
+    double carrier_phase;
+
+    /**
+     * 1-Sigma uncertainty of the carrier-phase.
+     * If the data is available, 'flags' must contain
+     * GNSS_MEASUREMENT_HAS_CARRIER_PHASE_UNCERTAINTY.
+     */
+    double carrier_phase_uncertainty;
+
+    /**
+     * An enumeration that indicates the 'multipath' state of the event.
+     *
+     * The multipath Indicator is intended to report the presence of overlapping
+     * signals that manifest as distorted correlation peaks.
+     *
+     * - if there is a distorted correlation peak shape, report that multipath
+     *   is GNSS_MULTIPATH_INDICATOR_PRESENT.
+     * - if there is not a distorted correlation peak shape, report
+     *   GNSS_MULTIPATH_INDICATOR_NOT_PRESENT
+     * - if signals are too weak to discern this information, report
+     *   GNSS_MULTIPATH_INDICATOR_UNKNOWN
+     *
+     * Example: when doing the standardized overlapping Multipath Performance
+     * test (3GPP TS 34.171) the Multipath indicator should report
+     * GNSS_MULTIPATH_INDICATOR_PRESENT for those signals that are tracked, and
+     * contain multipath, and GNSS_MULTIPATH_INDICATOR_NOT_PRESENT for those
+     * signals that are tracked and do not contain multipath.
+     */
+    MTK_HAL_GnssMultipathIndicator multipath_indicator;
+
+    /**
+     * Signal-to-noise ratio at correlator output in dB.
+     * If the data is available, 'flags' must contain GNSS_MEASUREMENT_HAS_SNR.
+     * This is the power ratio of the "correlation peak height above the
+     * observed noise floor" to "the noise RMS".
+     */
+    double snr_db;
+
+    /**
+       * Automatic gain control (AGC) level. AGC acts as a variable gain
+       * amplifier adjusting the power of the incoming signal. The AGC level
+       * may be used to indicate potential interference. When AGC is at a
+       * nominal level, this value must be set as 0. Higher gain (and/or lower
+       * input power) must be output as a positive number. Hence in cases of
+       * strong jamming, in the band of this signal, this value must go more
+       * negative.
+       */
+    double agc_level_db;
+} gnss_measurement;
+
+typedef struct {
+    /** Number of measurements. */
+    size_t measurement_count;
+
+    /** The array of measurements. */
+    gps_measurement measurements[GPS_MAX_MEASUREMENT];
+
+    /** The GPS clock time reading. */
+    gps_clock clock;
+} gps_data;
+
+/**
+ * Represents a reading of GNSS measurements. For devices where GnssSystemInfo's
+ * year_of_hw is set to 2016+, it is mandatory that these be provided, on
+ * request, when the GNSS receiver is searching/tracking signals.
+ *
+ * - Reporting of GPS constellation measurements is mandatory.
+ * - Reporting of all tracked constellations are encouraged.
+ */
+typedef struct {
+    /** Number of measurements. */
+    size_t measurement_count;
+
+    /** The array of measurements. */
+    gnss_measurement measurements[MTK_HAL_GNSS_MAX_MEASUREMENT];
+
+    /** The GPS clock time reading. */
+    gnss_clock clock;
+} gnss_data;
+
+typedef struct {
+    /**
+     * Pseudo-random number in the range of [1, 32]
+     * This is a Mandatory value.
+     */
+    int8_t prn;
+
+    /**
+     * The type of message contained in the structure.
+     * This is a Mandatory value.
+     */
+    gps_nav_msg_type type;
+
+    /**
+     * The status of the received navigation message.
+     * No need to send any navigation message that contains words with parity error and cannot be
+     * corrected.
+     */
+    nav_msg_status status;
+
+    /**
+     * Message identifier.
+     * It provides an index so the complete Navigation Message can be assembled. i.e. fo L1 C/A
+     * subframe 4 and 5, this value corresponds to the 'frame id' of the navigation message.
+     * Subframe 1, 2, 3 does not contain a 'frame id' and this value can be set to -1.
+     */
+    short message_id;
+
+    /**
+     * Sub-message identifier.
+     * If required by the message 'type', this value contains a sub-index within the current
+     * message (or frame) that is being transmitted.
+     * i.e. for L1 C/A the submessage id corresponds to the sub-frame id of the navigation message.
+     */
+    short submessage_id;
+
+    /**
+     * The length of the data (in bytes) contained in the current message.
+     * If this value is different from zero, 'data' must point to an array of the same size.
+     * e.g. for L1 C/A the size of the sub-frame will be 40 bytes (10 words, 30 bits/word).
+     * This is a Mandatory value.
+     */
+    size_t data_length;
+
+    /**
+     * The data of the reported GPS message.
+     * The bytes (or words) specified using big endian format (MSB first).
+     *
+     * For L1 C/A, each subframe contains 10 30-bit GPS words. Each GPS word (30 bits) should be
+     * fitted into the last 30 bits in a 4-byte word (skip B31 and B32), with MSB first.
+     */
+    char data[40];
+} gps_nav_msg;
+
+/** Represents a GPS navigation message (or a fragment of it). */
+typedef struct {
+    /** set to sizeof(GnssNavigationMessage) */
+    size_t size;
+
+    /**
+     * Satellite vehicle ID number, as defined in GnssSvInfo::svid
+     * This is a mandatory value.
+     */
+    int16_t svid;
+
+    /**
+     * The type of message contained in the structure.
+     * This is a mandatory value.
+     */
+    MTK_HAL_GnssNavigationMessageType type;
+
+    /**
+     * The status of the received navigation message.
+     * No need to send any navigation message that contains words with parity error and cannot be
+     * corrected.
+     */
+    MTK_HAL_NavigationMessageStatus status;
+
+    /**
+     * Message identifier. It provides an index so the complete Navigation
+     * Message can be assembled.
+     *
+     * - For GPS L1 C/A subframe 4 and 5, this value corresponds to the 'frame
+     *   id' of the navigation message, in the range of 1-25 (Subframe 1, 2, 3
+     *   does not contain a 'frame id' and this value can be set to -1.)
+     *
+     * - For Glonass L1 C/A, this refers to the frame ID, in the range of 1-5.
+     *
+     * - For BeiDou D1, this refers to the frame number in the range of 1-24
+     *
+     * - For Beidou D2, this refers to the frame number, in the range of 1-120
+     *
+     * - For Galileo F/NAV nominal frame structure, this refers to the subframe
+     *   number, in the range of 1-12
+     *
+     * - For Galileo I/NAV nominal frame structure, this refers to the subframe
+     *   number in the range of 1-24
+     */
+    int16_t message_id;
+
+    /**
+     * Sub-message identifier. If required by the message 'type', this value
+     * contains a sub-index within the current message (or frame) that is being
+     * transmitted.
+     *
+     * - For GPS L1 C/A, BeiDou D1 & BeiDou D2, the submessage id corresponds to
+     *   the subframe number of the navigation message, in the range of 1-5.
+     *
+     * - For Glonass L1 C/A, this refers to the String number, in the range from
+     *   1-15
+     *
+     * - For Galileo F/NAV, this refers to the page type in the range 1-6
+     *
+     * - For Galileo I/NAV, this refers to the word type in the range 1-10+
+     */
+    int16_t submessage_id;
+
+    /**
+     * The length of the data (in bytes) contained in the current message.
+     * If this value is different from zero, 'data' must point to an array of the same size.
+     * e.g. for L1 C/A the size of the sub-frame will be 40 bytes (10 words, 30 bits/word).
+     *
+     * This is a mandatory value.
+     */
+    size_t data_length;
+
+    /**
+     * The data of the reported GPS message. The bytes (or words) specified
+     * using big endian format (MSB first).
+     *
+     * - For GPS L1 C/A, Beidou D1 & Beidou D2, each subframe contains 10 30-bit
+     *   words. Each word (30 bits) should be fit into the last 30 bits in a
+     *   4-byte word (skip B31 and B32), with MSB first, for a total of 40
+     *   bytes, covering a time period of 6, 6, and 0.6 seconds, respectively.
+     *
+     * - For Glonass L1 C/A, each string contains 85 data bits, including the
+     *   checksum.  These bits should be fit into 11 bytes, with MSB first (skip
+     *   B86-B88), covering a time period of 2 seconds.
+     *
+     * - For Galileo F/NAV, each word consists of 238-bit (sync & tail symbols
+     *   excluded). Each word should be fit into 30-bytes, with MSB first (skip
+     *   B239, B240), covering a time period of 10 seconds.
+     *
+     * - For Galileo I/NAV, each page contains 2 page parts, even and odd, with
+     *   a total of 2x114 = 228 bits, (sync & tail excluded) that should be fit
+     *   into 29 bytes, with MSB first (skip B229-B232).
+     */
+    uint8_t* data;
+} gnss_nav_msg;
+
+#if 0
+void dump_gps_location(gps_location in);
+void dump_gnss_sv(gnss_sv in);
+void dump_gnss_sv_info(gnss_sv_info in);
+void dump_gps_data(gps_data in);
+void dump_gps_measurement(gps_measurement in);
+void dump_gps_clock(gps_clock in);
+void dump_gps_nav_msg(gps_nav_msg in);
+void dump_gnss_data(gnss_data in);
+void dump_gnss_measurement(gnss_measurement in);
+void dump_gnss_clock(gnss_clock in);
+void dump_gnss_nav_msg(gnss_nav_msg in);
+#endif
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
diff --git a/src/connectivity/gps/gps_hal/inc/hardware/gps_mtk.h b/src/connectivity/gps/gps_hal/inc/hardware/gps_mtk.h
new file mode 100644
index 0000000..df13674
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/inc/hardware/gps_mtk.h
@@ -0,0 +1,698 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_INCLUDE_HARDWARE_GPS_MTK_H
+#define ANDROID_INCLUDE_HARDWARE_GPS_MTK_H
+
+#if defined (__ANDROID_OS__)
+#include <hardware/gps_internal.h>
+#elif defined (__LINUX_OS__)
+#include "gps_internal.h"
+#endif
+
+__BEGIN_DECLS
+
+// MTK extended GpsAidingData values.
+#define GPS_DELETE_HOT_STILL 0x2000
+#define GPS_DELETE_EPO      0x4000
+
+// ====================vzw debug screen API =================
+/**
+ * Name for the VZW debug interface.
+ */
+#define VZW_DEBUG_INTERFACE      "vzw-debug"
+
+#define VZW_DEBUG_STRING_MAXLEN      200
+
+/** Represents data of VzwDebugData. */
+typedef struct {
+    /** set to sizeof(VzwDebugData) */
+    size_t size;
+
+    char  vzw_msg_data[VZW_DEBUG_STRING_MAXLEN];
+} VzwDebugData;
+
+
+typedef void (* vzw_debug_callback)(VzwDebugData* vzw_message);
+
+/** Callback structure for the Vzw debug interface. */
+typedef struct {
+    vzw_debug_callback vzw_debug_cb;
+} VzwDebugCallbacks;
+
+
+/** Extended interface for VZW DEBUG support. */
+typedef struct {
+    /** set to sizeof(VzwDebugInterface) */
+    size_t          size;
+
+    /** Registers the callbacks for Vzw debug message. */
+    int  (*init)( VzwDebugCallbacks* callbacks );
+
+    /** Set Vzw debug screen enable/disable **/
+    void (*set_vzw_debug_screen)(bool enabled);
+} VzwDebugInterface;
+
+////////////////////// GNSS HIDL v1.0 ////////////////////////////
+
+/** Represents a location. */
+typedef struct {
+    GpsLocation legacyLocation;
+    /**
+    * Represents expected horizontal position accuracy, radial, in meters
+    * (68% confidence).
+    */
+    float           horizontalAccuracyMeters;
+
+    /**
+    * Represents expected vertical position accuracy in meters
+    * (68% confidence).
+    */
+    float           verticalAccuracyMeters;
+
+    /**
+    * Represents expected speed accuracy in meter per seconds
+    * (68% confidence).
+    */
+    float           speedAccuracyMetersPerSecond;
+
+    /**
+    * Represents expected bearing accuracy in degrees
+    * (68% confidence).
+    */
+    float           bearingAccuracyDegrees;
+
+} GpsLocation_ext;
+
+
+typedef struct {
+    GnssSvInfo legacySvInfo;
+
+    /// v1.0 ///
+    float carrier_frequency;
+
+} GnssSvInfo_ext;
+
+/**
+ * Represents SV status.
+ */
+typedef struct {
+    /** set to sizeof(GnssSvStatus) */
+    size_t size;
+
+    /** Number of GPS SVs currently visible, refers to the SVs stored in sv_list */
+    int num_svs;
+    /**
+     * Pointer to an array of SVs information for all GNSS constellations,
+     * except GPS, which is reported using sv_list
+     */
+    GnssSvInfo_ext gnss_sv_list[GNSS_MAX_SVS];
+
+} GnssSvStatus_ext;
+
+/**
+ * Callback with location information. Can only be called from a thread created
+ * by create_thread_cb.
+ */
+typedef void (* gps_location_ext_callback)(GpsLocation_ext* location);
+
+/**
+ * Callback with SV status information.
+ * Can only be called from a thread created by create_thread_cb.
+ */
+typedef void (* gnss_sv_status_ext_callback)(GnssSvStatus_ext* sv_info);
+
+/**
+ * The callback associated with the geofence.
+ * Parameters:
+ *      geofence_id - The id associated with the add_geofence_area.
+ *      location    - The current GPS location.
+ *      transition  - Can be one of GPS_GEOFENCE_ENTERED, GPS_GEOFENCE_EXITED,
+ *                    GPS_GEOFENCE_UNCERTAIN.
+ *      timestamp   - Timestamp when the transition was detected.
+ *
+ * The callback should only be called when the caller is interested in that
+ * particular transition. For instance, if the caller is interested only in
+ * ENTERED transition, then the callback should NOT be called with the EXITED
+ * transition.
+ *
+ * IMPORTANT: If a transition is triggered resulting in this callback, the GPS
+ * subsystem will wake up the application processor, if its in suspend state.
+ */
+typedef void (*gps_geofence_transition_ext_callback) (int32_t geofence_id,
+        GpsLocation_ext* location, int32_t transition, GpsUtcTime timestamp);
+
+/**
+ * The callback associated with the availability of the GPS system for geofencing
+ * monitoring. If the GPS system determines that it cannot monitor geofences
+ * because of lack of reliability or unavailability of the GPS signals, it will
+ * call this callback with GPS_GEOFENCE_UNAVAILABLE parameter.
+ *
+ * Parameters:
+ *  status - GPS_GEOFENCE_UNAVAILABLE or GPS_GEOFENCE_AVAILABLE.
+ *  last_location - Last known location.
+ */
+typedef void (*gps_geofence_status_ext_callback) (int32_t status,
+        GpsLocation_ext* last_location);
+
+typedef struct {
+    gps_geofence_transition_ext_callback geofence_transition_callback;
+    gps_geofence_status_ext_callback geofence_status_callback;
+    gps_geofence_add_callback geofence_add_callback;
+    gps_geofence_remove_callback geofence_remove_callback;
+    gps_geofence_pause_callback geofence_pause_callback;
+    gps_geofence_resume_callback geofence_resume_callback;
+    gps_create_thread create_thread_cb;
+} GpsGeofenceCallbacks_ext;
+
+/** Extended interface for GPS_Geofencing support */
+typedef struct {
+   /** set to sizeof(GpsGeofencingInterface) */
+   size_t          size;
+
+   /**
+    * Opens the geofence interface and provides the callback routines
+    * to the implementation of this interface.
+    */
+   void  (*init)( GpsGeofenceCallbacks_ext* callbacks );
+
+   /**
+    * Add a geofence area. This api currently supports circular geofences.
+    * Parameters:
+    *    geofence_id - The id for the geofence. If a geofence with this id
+    *       already exists, an error value (GPS_GEOFENCE_ERROR_ID_EXISTS)
+    *       should be returned.
+    *    latitude, longtitude, radius_meters - The lat, long and radius
+    *       (in meters) for the geofence
+    *    last_transition - The current state of the geofence. For example, if
+    *       the system already knows that the user is inside the geofence,
+    *       this will be set to GPS_GEOFENCE_ENTERED. In most cases, it
+    *       will be GPS_GEOFENCE_UNCERTAIN.
+    *    monitor_transition - Which transitions to monitor. Bitwise OR of
+    *       GPS_GEOFENCE_ENTERED, GPS_GEOFENCE_EXITED and
+    *       GPS_GEOFENCE_UNCERTAIN.
+    *    notification_responsiveness_ms - Defines the best-effort description
+    *       of how soon should the callback be called when the transition
+    *       associated with the Geofence is triggered. For instance, if set
+    *       to 1000 millseconds with GPS_GEOFENCE_ENTERED, the callback
+    *       should be called 1000 milliseconds within entering the geofence.
+    *       This parameter is defined in milliseconds.
+    *       NOTE: This is not to be confused with the rate that the GPS is
+    *       polled at. It is acceptable to dynamically vary the rate of
+    *       sampling the GPS for power-saving reasons; thus the rate of
+    *       sampling may be faster or slower than this.
+    *    unknown_timer_ms - The time limit after which the UNCERTAIN transition
+    *       should be triggered. This parameter is defined in milliseconds.
+    *       See above for a detailed explanation.
+    */
+   void (*add_geofence_area) (int32_t geofence_id, double latitude, double longitude,
+       double radius_meters, int last_transition, int monitor_transitions,
+       int notification_responsiveness_ms, int unknown_timer_ms);
+
+   /**
+    * Pause monitoring a particular geofence.
+    * Parameters:
+    *   geofence_id - The id for the geofence.
+    */
+   void (*pause_geofence) (int32_t geofence_id);
+
+   /**
+    * Resume monitoring a particular geofence.
+    * Parameters:
+    *   geofence_id - The id for the geofence.
+    *   monitor_transitions - Which transitions to monitor. Bitwise OR of
+    *       GPS_GEOFENCE_ENTERED, GPS_GEOFENCE_EXITED and
+    *       GPS_GEOFENCE_UNCERTAIN.
+    *       This supersedes the value associated provided in the
+    *       add_geofence_area call.
+    */
+   void (*resume_geofence) (int32_t geofence_id, int monitor_transitions);
+
+   /**
+    * Remove a geofence area. After the function returns, no notifications
+    * should be sent.
+    * Parameter:
+    *   geofence_id - The id for the geofence.
+    */
+   void (*remove_geofence_area) (int32_t geofence_id);
+} GpsGeofencingInterface_ext;
+
+typedef struct {
+    GnssMeasurement legacyMeasurement;
+
+    /**
+     * Automatic gain control (AGC) level. AGC acts as a variable gain
+     * amplifier adjusting the power of the incoming signal. The AGC level
+     * may be used to indicate potential interference. When AGC is at a
+     * nominal level, this value must be set as 0. Higher gain (and/or lower
+     * input power) must be output as a positive number. Hence in cases of
+     * strong jamming, in the band of this signal, this value must go more
+     * negative.
+     *
+     * Note: Different hardware designs (e.g. antenna, pre-amplification, or
+     * other RF HW components) may also affect the typical output of of this
+     * value on any given hardware design in an open sky test - the
+     * important aspect of this output is that changes in this value are
+     * indicative of changes on input signal power in the frequency band for
+     * this measurement.
+     */
+    double agc_level_db;
+} GnssMeasurement_ext;
+
+/**
+ * Represents a reading of GNSS measurements. For devices where GnssSystemInfo's
+ * year_of_hw is set to 2016+, it is mandatory that these be provided, on
+ * request, when the GNSS receiver is searching/tracking signals.
+ *
+ * - Reporting of GPS constellation measurements is mandatory.
+ * - Reporting of all tracked constellations are encouraged.
+ */
+typedef struct {
+    /** set to sizeof(GnssData) */
+    size_t size;
+
+    /** Number of measurements. */
+    size_t measurement_count;
+
+    /** The array of measurements. */
+    GnssMeasurement_ext measurements[GNSS_MAX_MEASUREMENT];
+
+    /** The GPS clock time reading. */
+    GnssClock clock;
+} GnssData_ext;
+
+/**
+ * The callback for to report measurements from the HAL.
+ *
+ * Parameters:
+ *    data - A data structure containing the measurements.
+ */
+typedef void (*gnss_measurement_ext_callback) (GnssData_ext* data);
+
+typedef struct {
+    /** set to sizeof(GpsMeasurementCallbacks) */
+    size_t size;
+    gps_measurement_callback measurement_callback;
+    gnss_measurement_ext_callback gnss_measurement_callback;
+} GpsMeasurementCallbacks_ext;
+
+
+/////// Gnss debug ////
+
+/** Milliseconds since January 1, 1970 */
+typedef int64_t GnssUtcTime;
+
+typedef enum {
+    /** Ephemeris is known for this satellite. */
+    EPHEMERIS,
+    /**
+     * Ephemeris is not known, but Almanac (approximate location) is known.
+     */
+    ALMANAC_ONLY,
+    /**
+     * Both ephemeris & almanac are not known (e.g. during a cold start
+     * blind search.)
+     */
+    NOT_AVAILABLE
+} SatelliteEphemerisType;
+
+typedef enum {
+    /**
+     * The ephemeris (or almanac only) information was demodulated from the
+     * signal received on the device
+     */
+    DEMODULATED,
+    /**
+     * The ephemeris (or almanac only) information was received from a SUPL
+     * server.
+     */
+    SUPL_PROVIDED,
+    /**
+     * The ephemeris (or almanac only) information was provided by another
+     * server.
+     */
+    OTHER_SERVER_PROVIDED,
+    /**
+     * The ephemeris (or almanac only) information was provided by another
+     * method, e.g. injected via a local debug tool, from build defaults
+     * (e.g. almanac), or is from a satellite
+     * with SatelliteEphemerisType::NOT_AVAILABLE.
+     */
+    OTHER
+} SatelliteEphemerisSource;
+
+typedef enum {
+    /** The ephemeris is known good. */
+    GOOD,
+    /** The ephemeris is known bad. */
+    BAD,
+    /** The ephemeris is unknown to be good or bad. */
+    UNKNOWN
+} SatelliteEphemerisHealth;
+
+/**
+ * Provides the current best known position from any
+ * source (GNSS or injected assistance).
+ */
+typedef struct {
+    /**
+     * Validity of the data in this struct. False only if no
+     * latitude/longitude information is known.
+     */
+    bool valid;
+    /** Latitude expressed in degrees */
+    double latitudeDegrees;
+    /** Longitude expressed in degrees */
+    double longitudeDegrees;
+    /** Altitude above ellipsoid expressed in meters */
+    float altitudeMeters;
+    /** Represents horizontal speed in meters per second. */
+    float speedMetersPerSec;
+    /** Represents heading in degrees. */
+    float bearingDegrees;
+    /**
+     * Estimated horizontal accuracy of position expressed in meters,
+     * radial, 68% confidence.
+     */
+    double horizontalAccuracyMeters;
+    /**
+     * Estimated vertical accuracy of position expressed in meters, with
+     * 68% confidence.
+     */
+    double verticalAccuracyMeters;
+    /**
+     * Estimated speed accuracy in meters per second with 68% confidence.
+     */
+    double speedAccuracyMetersPerSecond;
+    /**
+     * estimated bearing accuracy degrees with 68% confidence.
+     */
+    double bearingAccuracyDegrees;
+    /**
+     * Time duration before this report that this position information was
+     * valid.  This can, for example, be a previous injected location with
+     * an age potentially thousands of seconds old, or
+     * extrapolated to the current time (with appropriately increased
+     * accuracy estimates), with a (near) zero age.
+     */
+    float ageSeconds;
+} PositionDebug;
+
+/**
+ * Provides the current best known UTC time estimate.
+ * If no fresh information is available, e.g. after a delete all,
+ * then whatever the effective defaults are on the device must be
+ * provided (e.g. Jan. 1, 2017, with an uncertainty of 5 years) expressed
+ * in the specified units.
+ */
+typedef struct {
+    /** UTC time estimate. */
+    GnssUtcTime timeEstimate;
+    /** 68% error estimate in time. */
+    float timeUncertaintyNs;
+    /**
+     * 68% error estimate in local clock drift,
+     * in nanoseconds per second (also known as parts per billion - ppb.)
+     */
+    float frequencyUncertaintyNsPerSec;
+} TimeDebug;
+
+/**
+ * Provides a single satellite info that has decoded navigation data.
+ */
+typedef struct {
+    /** Satellite vehicle ID number */
+    int16_t svid;
+    /** Defines the constellation type of the given SV. */
+    GnssConstellationType constellation;
+
+    /**
+     * Defines the standard broadcast ephemeris or almanac availability for
+     * the satellite.  To report status of predicted orbit and clock
+     * information, see the serverPrediction fields below.
+     */
+    SatelliteEphemerisType ephemerisType;
+    /** Defines the ephemeris source of the satellite. */
+    SatelliteEphemerisSource ephemerisSource;
+    /**
+     * Defines whether the satellite is known healthy
+     * (safe for use in location calculation.)
+     */
+    SatelliteEphemerisHealth ephemerisHealth;
+    /**
+     * Time duration from this report (current time), minus the
+     * effective time of the ephemeris source (e.g. TOE, TOA.)
+     * Set to 0 when ephemerisType is NOT_AVAILABLE.
+     */
+    float ephemerisAgeSeconds;
+
+    /**
+     * True if a server has provided a predicted orbit and clock model for
+     * this satellite.
+     */
+    bool serverPredictionIsAvailable;
+    /**
+     * Time duration from this report (current time) minus the time of the
+     * start of the server predicted information.  For example, a 1 day
+     * old prediction would be reported as 86400 seconds here.
+     */
+    float serverPredictionAgeSeconds;
+} SatelliteData;
+
+/**
+ * Provides a set of debug information that is filled by the GNSS chipset
+ * when the method getDebugData() is invoked.
+ */
+typedef struct {
+    /** Current best known position. */
+    PositionDebug position;
+    /** Current best know time estimate */
+    TimeDebug time;
+    /**
+     * Provides a list of the available satellite data, for all
+     * satellites and constellations the device can track,
+     * including GnssConstellationType UNKNOWN.
+     */
+    SatelliteData satelliteDataArray[GNSS_MAX_SVS];
+} DebugData;
+
+
+/** Extended interface for DEBUG support. */
+typedef struct {
+    /** set to sizeof(GpsDebugInterface) */
+    size_t          size;
+
+    /**
+     * This function should return any information that the native
+     * implementation wishes to include in a bugreport.
+     */
+    // size_t (*get_internal_state)(char* buffer, size_t bufferSize);
+    /// v1.0 ///
+    bool (*get_internal_state)(DebugData* debugData);
+} GpsDebugInterface_ext;
+
+
+////////////////////// GNSS HIDL v1.1 ////////////////////////////
+
+/**
+ * Callback for reporting driver name information.
+ */
+typedef void (* gnss_set_name_callback)(const char* name, int length);
+
+/**
+ * Callback for requesting framework NLP or Fused location injection.
+ */
+typedef void (* gnss_request_location_callback)(bool independentFromGnss);
+
+/** New GPS callback structure. */
+typedef struct {
+    /** set to sizeof(GpsCallbacks) */
+    size_t      size;
+    gps_location_ext_callback location_cb;
+    gps_status_callback status_cb;
+    gps_sv_status_callback sv_status_cb;
+    gps_nmea_callback nmea_cb;
+    gps_set_capabilities set_capabilities_cb;
+    gps_acquire_wakelock acquire_wakelock_cb;
+    gps_release_wakelock release_wakelock_cb;
+    gps_create_thread create_thread_cb;
+    gps_request_utc_time request_utc_time_cb;
+
+    gnss_set_system_info set_system_info_cb;
+    gnss_sv_status_ext_callback gnss_sv_status_cb;
+
+    /////v1.1////
+    gnss_set_name_callback set_name_cb;
+    gnss_request_location_callback request_location_cb;
+} GpsCallbacks_ext;
+
+
+/** Represents the standard GPS interface. */
+typedef struct {
+    /** set to sizeof(GpsInterface) */
+    size_t          size;
+    /**
+     * Opens the interface and provides the callback routines
+     * to the implementation of this interface.
+     */
+    /// v1.0 ///
+//    int   (*init)( GpsCallbacks* callbacks );
+    /// v1.1 ///
+    int   (*init)( GpsCallbacks_ext* callbacks );
+
+    /** Starts navigating. */
+    int   (*start)( void );
+
+    /** Stops navigating. */
+    int   (*stop)( void );
+
+    /** Closes the interface. */
+    void  (*cleanup)( void );
+
+    /** Injects the current time. */
+    int   (*inject_time)(GpsUtcTime time, int64_t timeReference,
+                         int uncertainty);
+
+    /**
+     * Injects current location from another location provider (typically cell
+     * ID). Latitude and longitude are measured in degrees expected accuracy is
+     * measured in meters
+     */
+    int  (*inject_location)(double latitude, double longitude, float accuracy);
+
+    /**
+     * Specifies that the next call to start will not use the
+     * information defined in the flags. GPS_DELETE_ALL is passed for
+     * a cold start.
+     */
+    void  (*delete_aiding_data)(GpsAidingData flags);
+
+    /**
+     * min_interval represents the time between fixes in milliseconds.
+     * preferred_accuracy represents the requested fix accuracy in meters.
+     * preferred_time represents the requested time to first fix in milliseconds.
+     *
+     * 'mode' parameter should be one of GPS_POSITION_MODE_MS_BASED
+     * or GPS_POSITION_MODE_STANDALONE.
+     * It is allowed by the platform (and it is recommended) to fallback to
+     * GPS_POSITION_MODE_MS_BASED if GPS_POSITION_MODE_MS_ASSISTED is passed in, and
+     * GPS_POSITION_MODE_MS_BASED is supported.
+     */
+     /// v1.0 ///
+//    int   (*set_position_mode)(GpsPositionMode mode, GpsPositionRecurrence recurrence,
+//            uint32_t min_interval, uint32_t preferred_accuracy, uint32_t preferred_time);
+    /// v1.1 ///
+    int   (*set_position_mode)(GpsPositionMode mode, GpsPositionRecurrence recurrence,
+            uint32_t min_interval, uint32_t preferred_accuracy, uint32_t preferred_time,
+            bool lowPowerMode);
+
+
+    /** Get a pointer to extension information. */
+    const void* (*get_extension)(const char* name);
+
+    /// v1.1 ///
+    int  (*inject_fused_location)(double latitude, double longitude, float accuracy);
+
+} GpsInterface_ext;
+
+
+/**
+ * Extended interface for GPS Measurements support.
+ */
+typedef struct {
+    /** Set to sizeof(GpsMeasurementInterface_ext) */
+    size_t size;
+
+    /**
+     * Initializes the interface and registers the callback routines with the HAL.
+     * After a successful call to 'init' the HAL must begin to provide updates at its own phase.
+     *
+     * Status:
+     *    GPS_MEASUREMENT_OPERATION_SUCCESS
+     *    GPS_MEASUREMENT_ERROR_ALREADY_INIT - if a callback has already been registered without a
+     *              corresponding call to 'close'
+     *    GPS_MEASUREMENT_ERROR_GENERIC - if any other error occurred, it is expected that the HAL
+     *              will not generate any updates upon returning this error code.
+     */
+    /// v1.0 ///
+//    int (*init) (GpsMeasurementCallbacks* callbacks);
+    /// v1.1 ///
+    int (*init) (GpsMeasurementCallbacks_ext* callbacks, bool enableFullTracking);
+
+    /**
+     * Stops updates from the HAL, and unregisters the callback routines.
+     * After a call to stop, the previously registered callbacks must be considered invalid by the
+     * HAL.
+     * If stop is invoked without a previous 'init', this function should perform no work.
+     */
+    void (*close) ();
+
+} GpsMeasurementInterface_ext;
+
+
+/**
+ * Interface for passing GNSS configuration contents from platform to HAL.
+ */
+typedef struct {
+    /** Set to sizeof(GnssConfigurationInterface) */
+    size_t size;
+
+    /**
+     * Deliver GNSS configuration contents to HAL.
+     * Parameters:
+     *     config_data - a pointer to a char array which holds what usually is expected from
+                         file(/etc/gps.conf), i.e., a sequence of UTF8 strings separated by '\n'.
+     *     length - total number of UTF8 characters in configuraiton data.
+     *
+     * IMPORTANT:
+     *      GPS HAL should expect this function can be called multiple times. And it may be
+     *      called even when GpsLocationProvider is already constructed and enabled. GPS HAL
+     *      should maintain the existing requests for various callback regardless the change
+     *      in configuration data.
+     */
+    void (*configuration_update) (const char* config_data, int32_t length);
+
+   //// v1.1 ////
+   void (*setBlacklist) (long long* blacklist, int32_t size);
+} GnssConfigurationInterface_ext;
+
+
+#if defined (__ANDROID_OS__)
+struct gps_device_t_ext {
+    struct hw_device_t common;
+
+    /**
+     * Set the provided lights to the provided values.
+     *
+     * Returns: 0 on succes, error code on failure.
+     */
+    const GpsInterface_ext* (*get_gps_interface)(struct gps_device_t_ext* dev);
+};
+#elif defined (__LINUX_OS__)
+struct gps_device_t_ext {
+    /**
+     * Set the provided lights to the provided values.
+     *
+     * Returns: 0 on succes, error code on failure.
+     */
+    const GpsInterface_ext* (*get_gps_interface)(struct gps_device_t_ext* dev);
+};
+#endif
+
+__END_DECLS
+
+#endif /* ANDROID_INCLUDE_HARDWARE_GPS_MTK_H */
+
diff --git a/src/connectivity/gps/gps_hal/inc/mtk_auto_log.h b/src/connectivity/gps/gps_hal/inc/mtk_auto_log.h
new file mode 100644
index 0000000..edf1775
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/inc/mtk_auto_log.h
@@ -0,0 +1,186 @@
+/*
+* Copyright Statement:
+*
+* This software/firmware and related documentation ("MediaTek Software") are
+* protected under relevant copyright laws. The information contained herein is
+* confidential and proprietary to MediaTek Inc. and/or its licensors. Without
+* the prior written permission of MediaTek inc. and/or its licensors, any
+* reproduction, modification, use or disclosure of MediaTek Software, and
+* information contained herein, in whole or in part, shall be strictly
+* prohibited.
+*
+* MediaTek Inc. (C) 2017. All rights reserved.
+*
+* BY OPENING THIS FILE, RECEIVER HEREBY UNEQUIVOCALLY ACKNOWLEDGES AND AGREES
+* THAT THE SOFTWARE/FIRMWARE AND ITS DOCUMENTATIONS ("MEDIATEK SOFTWARE")
+* RECEIVED FROM MEDIATEK AND/OR ITS REPRESENTATIVES ARE PROVIDED TO RECEIVER
+* ON AN "AS-IS" BASIS ONLY. MEDIATEK EXPRESSLY DISCLAIMS ANY AND ALL
+* WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED
+* WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR
+* NONINFRINGEMENT. NEITHER DOES MEDIATEK PROVIDE ANY WARRANTY WHATSOEVER WITH
+* RESPECT TO THE SOFTWARE OF ANY THIRD PARTY WHICH MAY BE USED BY,
+* INCORPORATED IN, OR SUPPLIED WITH THE MEDIATEK SOFTWARE, AND RECEIVER AGREES
+* TO LOOK ONLY TO SUCH THIRD PARTY FOR ANY WARRANTY CLAIM RELATING THERETO.
+* RECEIVER EXPRESSLY ACKNOWLEDGES THAT IT IS RECEIVER'S SOLE RESPONSIBILITY TO
+* OBTAIN FROM ANY THIRD PARTY ALL PROPER LICENSES CONTAINED IN MEDIATEK
+* SOFTWARE. MEDIATEK SHALL ALSO NOT BE RESPONSIBLE FOR ANY MEDIATEK SOFTWARE
+* RELEASES MADE TO RECEIVER'S SPECIFICATION OR TO CONFORM TO A PARTICULAR
+* STANDARD OR OPEN FORUM. RECEIVER'S SOLE AND EXCLUSIVE REMEDY AND MEDIATEK'S
+* ENTIRE AND CUMULATIVE LIABILITY WITH RESPECT TO THE MEDIATEK SOFTWARE
+* RELEASED HEREUNDER WILL BE, AT MEDIATEK'S OPTION, TO REVISE OR REPLACE THE
+* MEDIATEK SOFTWARE AT ISSUE, OR REFUND ANY SOFTWARE LICENSE FEES OR SERVICE
+* CHARGE PAID BY RECEIVER TO MEDIATEK FOR SUCH MEDIATEK SOFTWARE AT ISSUE.
+*/
+#ifndef MTK_AUTO_LOG_H
+#define MTK_AUTO_LOG_H
+
+/**
+ *  @enum LOG_LEVEL
+ *  @brief Define Log Level
+ */
+typedef enum {
+    L_VERBOSE = 0, L_DEBUG, L_INFO, L_WARN, L_ERROR, L_ASSERT, L_SUPPRESS
+} LOG_LEVEL;
+
+#ifndef UNUSED
+#define UNUSED(x) (x)=(x)
+#endif
+
+#ifdef LOGD
+#undef LOGD
+#endif
+#ifdef LOGW
+#undef LOGW
+#endif
+#ifdef LOGE
+#undef LOGE
+#endif
+
+#ifndef LOG_TAG
+#undef LOG_TAG
+#define LOG_TAG "gnss_hal"
+#endif
+
+#include <string.h>
+
+int set_log_level(int *dst_level, int src_level);
+
+extern int log_dbg_level;
+#define LOG_IS_ENABLED(level) (log_dbg_level <= level)
+
+#define FILE_NAME(x) strrchr(x, '/')?strrchr(x, '/') + 1 : x
+
+#if defined(__ANDROID_OS__)
+
+#define  ANDROID_MNLD_PROP_SUPPORT 1
+
+#include <cutils/sockets.h>
+#include <log/log.h>     /*logging in logcat*/
+#include <cutils/android_filesystem_config.h>
+#include <cutils/properties.h>
+
+#define PRINT_LOG(loglevel, fmt, args...) \
+        do {\
+                if (LOG_IS_ENABLED(loglevel)) {\
+                    switch (loglevel){\
+                        case L_ASSERT:\
+                        {\
+                            ALOG_ASSERT("%s %s %d " fmt, FILE_NAME(__FILE__), __FUNCTION__, __LINE__, ##args);\
+                            break;\
+                        }\
+                        case L_ERROR:\
+                        {\
+                            ALOGE("%s %s %d " fmt, FILE_NAME(__FILE__), __FUNCTION__, __LINE__, ##args);\
+                            break;\
+                        }\
+                        case L_WARN:\
+                        {\
+                            ALOGW("%s %s %d " fmt, FILE_NAME(__FILE__), __FUNCTION__, __LINE__, ##args);\
+                            break;\
+                        }\
+                        case L_INFO:\
+                        {\
+                            ALOGI("%s %s %d " fmt, FILE_NAME(__FILE__), __FUNCTION__, __LINE__, ##args);\
+                            break;\
+                        }\
+                        case L_DEBUG:\
+                        {\
+                            ALOGD("%s %s %d " fmt, FILE_NAME(__FILE__), __FUNCTION__, __LINE__, ##args);\
+                            break;\
+                        }\
+                        case L_VERBOSE:\
+                        {\
+                            ALOGV("%s %s %d " fmt, FILE_NAME(__FILE__), __FUNCTION__, __LINE__, ##args);\
+                            break;\
+                        }\
+                    }\
+                }\
+        } while (0)
+
+#define LOGA(fmt, args...)    PRINT_LOG(L_ASSERT, fmt, ##args)
+#define LOGE(fmt, args...)    PRINT_LOG(L_ERROR, fmt, ##args)
+#define LOGW(fmt, args...)    PRINT_LOG(L_WARN, fmt, ##args)
+#define LOGI(fmt, args...)    PRINT_LOG(L_INFO, fmt, ##args)
+#define LOGD(fmt, args...)    PRINT_LOG(L_DEBUG, fmt, ##args)
+#define LOGV(fmt, args...)    PRINT_LOG(L_VERBOSE, fmt, ##args)
+
+#define  TRC(f)       ALOGD("%s", __func__)
+
+#elif defined(__LINUX_OS__)
+
+#include <stdio.h>
+#define  ANDROID_MNLD_PROP_SUPPORT 0
+
+
+char time_buff[64];
+int get_time_str(char* buf, int len);
+
+#ifndef gettid
+#include <unistd.h>
+#include <sys/syscall.h>
+#define gettid() syscall(__NR_gettid)
+#define getpid() syscall(__NR_getpid)
+#endif
+
+#define PRINT_LOG(loglevel, tag, fmt, args...) \
+        do {\
+                if (LOG_IS_ENABLED(loglevel)) {\
+                    get_time_str(time_buff, sizeof(time_buff));\
+                    printf("%ld %ld [%s]" LOG_TAG tag "%s %s %d "  fmt "\n",\
+                        getpid(), gettid(),time_buff, FILE_NAME(__FILE__), __FUNCTION__, __LINE__, ##args);\
+                    fflush(stdout);\
+                }\
+        } while (0)
+
+#define LOGA(fmt, args...)    PRINT_LOG(L_ASSERT, "[ASSERT]: ", fmt, ##args)
+#define LOGE(fmt, args...)    PRINT_LOG(L_ERROR, "[ERROR]: ", fmt, ##args)
+#define LOGW(fmt, args...)    PRINT_LOG(L_WARN, "[WARNING]: ", fmt, ##args)
+#define LOGI(fmt, args...)    PRINT_LOG(L_INFO, "[INFO]: ", fmt, ##args)
+#define LOGD(fmt, args...)    PRINT_LOG(L_DEBUG, "[DEBUG]: ", fmt, ##args)
+#define LOGV(fmt, args...)    PRINT_LOG(L_VERBOSE, "[VERBOSE]: ", fmt, ##args)
+
+#define  TRC(f)       ((void)0)
+
+#elif defined(__TIZEN_OS__)
+
+#include <dlog/dlog.h>
+
+#define PRINT_LOG(loglevel, tag, fmt, args...) \
+        do {\
+                if (LOG_IS_ENABLED(loglevel)) {\
+                    dlog_print(DLOG_DEBUG, fmt "\n", ##args);\
+                    printf(fmt "\n", ##args);
+                    fflush(stdout);\
+                }\
+        } while (0)
+
+#define LOGA(fmt, args...)    PRINT_LOG(L_ASSERT, "[ASSERT]: ", fmt, ##args)
+#define LOGE(fmt, args...)    PRINT_LOG(L_ERROR, "[ERROR]: ", fmt, ##args)
+#define LOGW(fmt, args...)    PRINT_LOG(L_WARN, "[WARNING]: ", fmt, ##args)
+#define LOGI(fmt, args...)    PRINT_LOG(L_INFO, "[INFO]: ", fmt, ##args)
+#define LOGD(fmt, args...)    PRINT_LOG(L_DEBUG, "[DEBUG]: ", fmt, ##args)
+#define LOGV(fmt, args...)    PRINT_LOG(L_VERBOSE, "[VERBOSE]: ", fmt, ##args)
+
+#endif
+
+#endif
diff --git a/src/connectivity/gps/gps_hal/inc/mtk_lbs_utility.h b/src/connectivity/gps/gps_hal/inc/mtk_lbs_utility.h
new file mode 100644
index 0000000..3d8fafd
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/inc/mtk_lbs_utility.h
@@ -0,0 +1,87 @@
+#ifndef __MTK_LBS_UTILITY_H__
+#define __MTK_LBS_UTILITY_H__
+
+#include <time.h>
+#include <stdint.h>
+//#include "mtk_auto_log.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*************************************************
+* Basic Utilities
+**************************************************/
+#define  MTK_GPS_NVRAM  0
+
+#if defined(__ANDROID_OS__)
+#define  ANDROID_MNLD_PROP_SUPPORT 1
+#elif defined(__LINUX_OS__)
+#define  ANDROID_MNLD_PROP_SUPPORT 0
+#endif
+
+void msleep(int interval);
+
+#define MNLD_STRNCPY(dst,src,size) do{\
+                                       strncpy((char *)(dst), (src), (size - 1));\
+                                      (dst)[size - 1] = '\0';\
+                                     }while(0)
+
+/*************************************************
+* Timer
+**************************************************/
+typedef void (* timer_callback)();
+
+
+// in millisecond
+time_t get_tick();
+
+// in millisecond
+time_t get_time_in_millisecond();
+
+/*************************************************
+* Epoll
+**************************************************/
+// -1 means failure
+int epoll_add_fd(int epfd, int fd);
+
+// -1 failed
+int epoll_add_fd2(int epfd, int fd, uint32_t events);
+
+// -1 failed
+int epoll_del_fd(int epfd, int fd);
+
+int epoll_mod_fd(int epfd, int fd, uint32_t events);
+
+/*************************************************
+* Local UDP Socket
+**************************************************/
+// -1 means failure
+int socket_bind_udp(const char* path);
+
+// -1 means failure
+int socket_set_blocking(int fd, int blocking);
+
+// -1 means failure
+int safe_sendto(const char* path, const char* buff, int len);
+
+// -1 means failure
+int safe_recvfrom(int fd, char* buff, int len);
+
+// -1 means failure
+int start_timer(timer_t timerid, int milliseconds);
+
+// -1 means failure
+int stop_timer(timer_t timerid);
+
+// -1 means failure
+timer_t init_timer(timer_callback cb);
+
+// -1 means failure
+int deinit_timer(timer_t timerid);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/src/connectivity/gps/gps_hal/src/agpsinf.c b/src/connectivity/gps/gps_hal/src/agpsinf.c
new file mode 100644
index 0000000..c1ba646
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/src/agpsinf.c
@@ -0,0 +1,181 @@
+/* Copyright Statement:
+ *
+ * This software/firmware and related documentation ("MediaTek Software") are
+ * protected under relevant copyright laws. The information contained herein
+ * is confidential and proprietary to MediaTek Inc. and/or its licensors.
+ * Without the prior written permission of MediaTek inc. and/or its licensors,
+ * any reproduction, modification, use or disclosure of MediaTek Software,
+ * and information contained herein, in whole or in part, shall be strictly prohibited.
+ *
+ * MediaTek Inc. (C) 2016. All rights reserved.
+ *
+ * BY OPENING THIS FILE, RECEIVER HEREBY UNEQUIVOCALLY ACKNOWLEDGES AND AGREES
+ * THAT THE SOFTWARE/FIRMWARE AND ITS DOCUMENTATIONS ("MEDIATEK SOFTWARE")
+ * RECEIVED FROM MEDIATEK AND/OR ITS REPRESENTATIVES ARE PROVIDED TO RECEIVER ON
+ * AN "AS-IS" BASIS ONLY. MEDIATEK EXPRESSLY DISCLAIMS ANY AND ALL WARRANTIES,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NONINFRINGEMENT.
+ * NEITHER DOES MEDIATEK PROVIDE ANY WARRANTY WHATSOEVER WITH RESPECT TO THE
+ * SOFTWARE OF ANY THIRD PARTY WHICH MAY BE USED BY, INCORPORATED IN, OR
+ * SUPPLIED WITH THE MEDIATEK SOFTWARE, AND RECEIVER AGREES TO LOOK ONLY TO SUCH
+ * THIRD PARTY FOR ANY WARRANTY CLAIM RELATING THERETO. RECEIVER EXPRESSLY ACKNOWLEDGES
+ * THAT IT IS RECEIVER'S SOLE RESPONSIBILITY TO OBTAIN FROM ANY THIRD PARTY ALL PROPER LICENSES
+ * CONTAINED IN MEDIATEK SOFTWARE. MEDIATEK SHALL ALSO NOT BE RESPONSIBLE FOR ANY MEDIATEK
+ * SOFTWARE RELEASES MADE TO RECEIVER'S SPECIFICATION OR TO CONFORM TO A PARTICULAR
+ * STANDARD OR OPEN FORUM. RECEIVER'S SOLE AND EXCLUSIVE REMEDY AND MEDIATEK'S ENTIRE AND
+ * CUMULATIVE LIABILITY WITH RESPECT TO THE MEDIATEK SOFTWARE RELEASED HEREUNDER WILL BE,
+ * AT MEDIATEK'S OPTION, TO REVISE OR REPLACE THE MEDIATEK SOFTWARE AT ISSUE,
+ * OR REFUND ANY SOFTWARE LICENSE FEES OR SERVICE CHARGE PAID BY RECEIVER TO
+ * MEDIATEK FOR SUCH MEDIATEK SOFTWARE AT ISSUE.
+ *
+ * The following software/firmware and/or related documentation ("MediaTek Software")
+ * have been modified by MediaTek Inc. All revisions are subject to any receiver's
+ * applicable license agreements with MediaTek Inc.
+ */
+
+#include <string.h>
+
+#include "gpshal.h"
+#include "hal2mnl_interface.h"
+#include "mtk_lbs_utility.h"
+#include "mtk_auto_log.h"
+
+#ifdef LOG_TAG
+#undef LOG_TAG
+#define LOG_TAG "agpsinf"
+#endif
+
+//=========================================================
+// Agps Interface
+#ifndef __unused
+#define __unused
+#endif
+
+static void agpsinf_init(AGpsCallbacks* callbacks) {
+    g_gpshal_ctx.agps_cbs = callbacks;
+}
+
+static int agpsinf_set_server(AGpsType type, const char* hostname, int port) {
+    hal2mnl_set_server(type, hostname, port);
+    return 0;  // 0:ok,   non-zero: error; but GPS JNI will ignore it
+}
+
+static int agpsinf_data_conn_open_with_apn_ip_type(
+        const char* apn,
+        ApnIpType apnIpType) {
+    hal2mnl_data_conn_open_with_apn_ip_type(apn, apnIpType);
+    return 0;  // 0:ok,   non-zero: error; but GPS JNI will ignore it
+}
+
+const AGpsInterface mtk_agps_inf = {
+    sizeof(AGpsInterface),
+    agpsinf_init,
+    hal2mnl_data_conn_open,    // GPS JNI will ignore its ret value
+    hal2mnl_data_conn_closed,  // GPS JNI will ignore its ret value
+    hal2mnl_data_conn_failed,  // GPS JNI will ignore its ret value
+    agpsinf_set_server,
+    agpsinf_data_conn_open_with_apn_ip_type
+};
+
+
+//=========================================================
+// Gps Ni Interface
+
+static void gpsni_init(GpsNiCallbacks *callbacks) {
+    g_gpshal_ctx.gpsni_cbs = callbacks;
+}
+
+static void gpsni_respond(int notif_id, GpsUserResponseType user_response) {
+    hal2mnl_ni_respond(notif_id, user_response);
+}
+
+const GpsNiInterface  mtk_gps_ni_inf = {
+    sizeof(GpsNiInterface),
+    gpsni_init,
+    gpsni_respond
+};
+
+
+//=========================================================
+// Agps Ril Interface
+
+static void agps_ril_init(AGpsRilCallbacks* callbacks) {
+    g_gpshal_ctx.agpsril_cbs = callbacks;
+}
+
+static void agps_ril_set_ref_location(
+        const AGpsRefLocation *agps_reflocation,
+        __unused size_t sz_struct) {
+    // UNUSED(sz_struct);
+    uint16_t type = agps_reflocation->type;
+    switch (type) {
+        case AGPS_REF_LOCATION_TYPE_GSM_CELLID:
+        case AGPS_REF_LOCATION_TYPE_UMTS_CELLID: {
+            const AGpsRefLocationCellID cell = agps_reflocation->u.cellID;
+            hal2mnl_set_ref_location(
+                     type, cell.mcc, cell.mnc, cell.lac, cell.cid);
+            break;
+        }
+        // case AGPS_REG_LOCATION_TYPE_MAC:
+            // TODO: to support MAC when GPS JNI can support it
+            // break;
+        default:
+            LOGW("%s: unsupported ref loc type: %d", __func__, type);
+    }
+}
+
+static void agps_ril_set_set_id(AGpsSetIDType type, const char* setid) {
+    hal2mnl_set_id(type, setid);
+}
+
+static void agps_ril_ni_message(uint8_t *msg, size_t len) {
+    hal2mnl_ni_message((char*)msg, len);
+}
+
+static void agps_ril_update_network_state(int connected, int type, int roaming, const char* extra_info) {
+    hal2mnl_update_network_state(connected, type, roaming, extra_info);
+}
+
+static void agps_ril_update_network_availability(int available, const char* apn) {
+    hal2mnl_update_network_availability(available, apn);
+}
+
+const AGpsRilInterface mtk_agps_ril_inf = {
+    sizeof(AGpsRilInterface),
+    agps_ril_init,
+    agps_ril_set_ref_location,
+    agps_ril_set_set_id,
+    agps_ril_ni_message,
+    agps_ril_update_network_state,
+    agps_ril_update_network_availability
+};
+
+//=========================================================
+// Supl Certificate Interface
+
+#if 0  // not ready, even in GPS JNI
+static int suplcert_install_certificates(
+        __unused const DerEncodedCertificate* certificates,
+        __unused size_t length) {
+    UNUSED_VAR(certificates);
+    UNUSED_VAR(length);
+    // TODO: to use the new hal2mnl lib
+    return -1;
+}
+
+static int suplcert_revoke_certificates(
+        __unused const Sha1CertificateFingerprint* fingerprints,
+        __unused size_t length) {
+    UNUSED_VAR(fingerprints);
+    UNUSED_VAR(length);
+    // TODO: to use the new hal2mnl lib
+    return -1;
+}
+
+const SuplCertificateInterface mtk_supl_cert_inf = {
+    sizeof(SuplCertificateInterface),
+    suplcert_install_certificates,
+    suplcert_revoke_certificates,
+};
+#endif
+
diff --git a/src/connectivity/gps/gps_hal/src/data_coder.c b/src/connectivity/gps/gps_hal/src/data_coder.c
new file mode 100644
index 0000000..ab67b38
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/src/data_coder.c
@@ -0,0 +1,154 @@
+#include <string.h>
+
+#ifndef MAX
+#define MAX(A,B) ((A)>(B)?(A):(B))
+#endif
+#ifndef MIN
+#define MIN(A,B) ((A)<(B)?(A):(B))
+#endif
+
+//===============================================================
+// get
+char get_byte(char* buff, int* offset, int src_len) {
+    char ret = 0;
+    if (*offset >= 0 && *offset < src_len) {
+        ret = buff[*offset];
+        *offset += 1;
+    }
+    return ret;
+}
+
+short get_short(char* buff, int* offset, int src_len) {
+    short ret = 0;
+    ret |= get_byte(buff, offset, src_len) & 0xff;
+    ret |= (get_byte(buff, offset, src_len) << 8);
+    return ret;
+}
+
+int get_int(char* buff, int* offset, int src_len) {
+    int ret = 0;
+    ret |= get_short(buff, offset, src_len) & 0xffff;
+    ret |= (get_short(buff, offset, src_len) << 16);
+    return ret;
+}
+
+long long get_long(char* buff, int* offset, int src_len) {
+    long long ret = 0;
+    ret |= get_int(buff, offset, src_len) & 0xffffffffL;
+    ret |= ((long long)get_int(buff, offset, src_len) << 32);
+    return ret;
+}
+
+float get_float(char* buff, int* offset, int src_len) {
+    float ret;
+    int tmp = get_int(buff, offset, src_len);
+    ret = *((float*)&tmp);
+    return ret;
+}
+
+double get_double(char* buff, int* offset, int src_len) {
+    double ret;
+    long long tmp = get_long(buff, offset, src_len);
+    ret = *((double*)&tmp);
+    return ret;
+}
+
+char* get_string(char* buff, int* offset, int src_len) {
+    char ret = get_byte(buff, offset, src_len);
+    if (ret == 0) {
+        return NULL;
+    } else {
+        char* p = NULL;
+        int len = get_int(buff, offset, src_len);
+        if (*offset < 0 || *offset >= src_len) {
+            *offset = 0;
+        }
+        if ((len > src_len - *offset) || len < 0) {
+            len = src_len - *offset;
+        }
+        if (len <= 0) {
+            return NULL;
+        }
+        p = &buff[*offset];
+        p[len-1] = 0;
+        *offset += len;
+        return p;
+    }
+}
+
+char* get_string2(char* buff, int* offset, int src_len) {
+    char* output = get_string(buff, offset, src_len);
+    if (output == NULL) {
+        return "";
+    } else {
+        return output;
+    }
+}
+
+int get_binary(char* buff, int* offset, char* output, int src_len, int des_len) {
+    int len = 0;
+    if (*offset >= 0 && *offset <= src_len) {
+        len = get_int(buff, offset, src_len);
+        if (len > MIN((src_len-(*offset)), des_len)) {
+            len = MIN((src_len-(*offset)), des_len);
+        }
+        if (len > 0) {
+            memcpy(output, &buff[*offset], len);
+            *offset += len;
+        }
+    }
+    return len;
+}
+
+//===============================================================
+// put
+void put_byte(char* buff, int* offset, const char input) {
+    *((char*)&buff[*offset]) = input;
+    *offset += 1;
+}
+
+void put_short(char* buff, int* offset, const short input) {
+    put_byte(buff, offset, input & 0xff);
+    put_byte(buff, offset, (input >> 8) & 0xff);
+}
+
+void put_int(char* buff, int* offset, const int input) {
+    put_short(buff, offset, input & 0xffff);
+    put_short(buff, offset, (input >> 16) & 0xffff);
+}
+
+void put_long(char* buff, int* offset, const long long input) {
+    put_int(buff, offset, input & 0xffffffffL);
+    put_int(buff, offset, ((input >> 32L) & 0xffffffffL));
+}
+
+void put_float(char* buff, int* offset, const float input) {
+    int* data = (int*)&input;
+    put_int(buff, offset, *data);
+}
+
+void put_double(char* buff, int* offset, const double input) {
+    long long* data = (long long*)&input;
+    put_long(buff, offset, *data);
+}
+
+void put_string(char* buff, int* offset, const char* input) {
+    if (input == NULL) {
+        put_byte(buff, offset, 0);
+    } else {
+        int len = strlen(input) + 1;
+        put_byte(buff, offset, 1);
+        put_int(buff, offset, len);
+        memcpy(&buff[*offset], input, len);
+        *offset += len;
+    }
+}
+
+void put_binary(char* buff, int* offset, const char* input, const int len) {
+    put_int(buff, offset, len);
+    if (len > 0) {
+        memcpy(&buff[*offset], input, len);
+        *offset += len;
+    }
+}
+
diff --git a/src/connectivity/gps/gps_hal/src/geofenceinf.c b/src/connectivity/gps/gps_hal/src/geofenceinf.c
new file mode 100644
index 0000000..78c229f
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/src/geofenceinf.c
@@ -0,0 +1,153 @@
+#include "gpshal.h"

+#include "geofencehal_worker.h"

+#include "mtk_auto_log.h"

+#include <stdio.h>

+#include <inttypes.h>

+

+#ifndef UNUSED

+#define UNUSED(x) (x)=(x)

+#endif

+

+/**********************************************************

+ *  Global Variables                                      *

+ **********************************************************/

+extern unsigned int gConfigHalGeofence;

+

+/*********************************************************/

+/* FLP Geofence Interface implementation                 */

+/*********************************************************/

+void mtk_hal_geofence_init(GpsGeofenceCallbacks* callbacks) {

+    hal2_geofence_init();

+    LOGD("init geofence, cb function : %p",callbacks);

+    g_gpshal_ctx.geofence_cbs= callbacks;

+    return;

+}

+

+void mtk_hal_geofence_add_geofences(int32_t geofence_id, double latitude, double longitude,

+    double radius_meters, int last_transition, int monitor_transitions,

+    int notification_responsiveness_ms, int unknown_timer_ms) {

+    MTK_GEOFENCE_PROPERTY_T dbg_fence;

+

+    if(!is_gfc_exist()) {

+        LOGE("gfc not exist");

+        return;

+    }

+    dbg_fence.geofence_id = geofence_id;

+    dbg_fence.latitude = latitude;

+    dbg_fence.longitude = longitude;

+    dbg_fence.radius = radius_meters;

+    dbg_fence.last_transition = last_transition;

+    dbg_fence.monitor_transition = monitor_transitions;

+    dbg_fence.notification_period = notification_responsiveness_ms;

+    dbg_fence.unknown_timer = unknown_timer_ms;

+    dbg_fence.alive = 1;

+    dbg_fence.latest_state = last_transition >> 1;

+    dbg_fence.config = gConfigHalGeofence;

+    mtk_geo_inject_info_get(dbg_fence.geofence_id, &dbg_fence.coordinate_dn, &dbg_fence.coordinate_de);

+    hal2_geofence_add_geofences(dbg_fence);

+    return;

+}

+

+void mtk_hal_geofence_pause_geofence(int32_t geofence_id) {

+    if(!is_gfc_exist()) {

+        LOGE("gfc not exist");

+        return;

+    }

+    hal2_geofence_pause_geofence(geofence_id);

+    return;

+}

+

+void mtk_hal_geofence_resume_geofence(int32_t geofence_id, int monitor_transitions) {

+    if(!is_gfc_exist()) {

+        LOGE("gfc not exist");

+        return;

+    }

+    hal2_geofence_resume_geofence(geofence_id,monitor_transitions);

+    return;

+}

+

+void mtk_hal_geofence_remove_geofences(int32_t geofence_id) {

+    if(!is_gfc_exist()) {

+        LOGE("gfc not exist");

+        return;

+    }

+    hal2_geofence_remove_geofences(geofence_id);

+    return;

+}

+

+/*************************************************************/

+/*  Handle message from mnl to GPS/Geofence HAL              */

+/*************************************************************/

+void mtk_geofence_transition_callbacks_proc(MTK_FLP_MSG_T *prmsg) {

+    int32_t geofence_id, transition;

+    GpsLocation location;

+    int64_t timestamp;

+    #ifdef MTK_64_PLATFORM

+    unsigned char ratio = 2; //32 to 64-bits

+    unsigned char padding_diff = 4;

+    unsigned char loc_in[128] = {0};

+    unsigned int sizeof_loc_in = sizeof(GpsLocation) - sizeof(size_t)/ratio - padding_diff;

+    #else

+    uint32_t sizeof_loc_in = sizeof(GpsLocation);

+    #endif

+    memcpy(&geofence_id, (((char*)prmsg)+sizeof(MTK_FLP_MSG_T)), sizeof(int32_t));

+    #ifdef MTK_64_PLATFORM

+    memcpy(loc_in, (((char*)prmsg)+sizeof(MTK_FLP_MSG_T)+sizeof(int32_t)), sizeof_loc_in);

+    mtk_loc_rearrange(loc_in, &location);

+    #else

+    memcpy(&location, (((char*)prmsg)+sizeof(MTK_FLP_MSG_T)+sizeof(int32_t)), sizeof_loc_in);

+    #endif

+    memcpy(&transition, (((char*)prmsg)+sizeof(MTK_FLP_MSG_T)+sizeof(int32_t)+sizeof_loc_in), sizeof(int32_t));

+    memcpy(&timestamp, (((char*)prmsg)+sizeof(MTK_FLP_MSG_T)+sizeof(int32_t)+sizeof_loc_in+sizeof(int32_t)), sizeof(int64_t));

+    LOGD("geo transition: id=%"PRId32", transition=%"PRId32", latlon=%lf,%lf",geofence_id,transition,location.latitude,location.longitude);

+

+    if(g_gpshal_ctx.geofence_cbs == NULL) {

+        LOGE("mtk_geofence_transition_callbacks_proc: NO geofence callbacks assigned");

+        return;

+    }

+

+    //geofence CB for transition ntf

+    if (set_buff_transition_fence(geofence_id, transition) == 0) {

+       g_gpshal_ctx.geofence_cbs->geofence_transition_callback(geofence_id, &location, transition, timestamp);

+    }

+}

+

+void mtk_geofence_callbacks_proc(MTK_FLP_MSG_T *prmsg) {

+    MTK_GEOFENCE_CALLBACK_T cbs;

+

+    memcpy(&cbs,(char*)prmsg+sizeof(MTK_FLP_MSG_T),sizeof(MTK_GEOFENCE_CALLBACK_T));

+    //LOGD("geo_cb_proc: id=%d, result=%d",cbs.cb_id,cbs.result);

+

+    if(g_gpshal_ctx.geofence_cbs == NULL) {

+        LOGE("mtk_geofence_callbacks_proc: NO geofence callbacks assigned");

+        return;

+    }

+    switch(cbs.cb_id) {

+    case GEOFENCE_ADD_CALLBACK:

+        g_gpshal_ctx.geofence_cbs->geofence_add_callback(cbs.geofence_id, cbs.result);

+        break;

+    case GEOFENCE_REMOVE_CALLBACK:

+        g_gpshal_ctx.geofence_cbs->geofence_remove_callback(cbs.geofence_id, cbs.result);

+        break;

+    case GEOFENCE_PAUSE_CALLBACK:

+        g_gpshal_ctx.geofence_cbs->geofence_pause_callback(cbs.geofence_id, cbs.result);

+        break;

+    case GEOFENCE_RESUME_CALLBACK:

+        g_gpshal_ctx.geofence_cbs->geofence_resume_callback(cbs.geofence_id, cbs.result);

+        break;

+    default:

+        LOGE("mtk_geofence_callbacks_proc: Unknown callback id:%d", cbs.cb_id);

+        break;

+    }

+}

+

+const GpsGeofencingInterface mtkGeofence_inf = {

+    sizeof(GpsGeofencingInterface),

+    mtk_hal_geofence_init,

+    mtk_hal_geofence_add_geofences,

+    mtk_hal_geofence_pause_geofence,

+    mtk_hal_geofence_resume_geofence,

+    mtk_hal_geofence_remove_geofences,

+};

+

+

diff --git a/src/connectivity/gps/gps_hal/src/gfchal_mnl_interface.c b/src/connectivity/gps/gps_hal/src/gfchal_mnl_interface.c
new file mode 100644
index 0000000..5215818
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/src/gfchal_mnl_interface.c
@@ -0,0 +1,717 @@
+#include <string.h>

+#include <stdio.h>

+#include <stdlib.h>

+#include <unistd.h>

+#include <fcntl.h>

+#include <sys/socket.h>

+#include <sys/types.h>

+#include <sys/stat.h>

+#include <sys/un.h>

+#include <errno.h>

+#include <inttypes.h>

+

+#include "geofencehal_worker.h"

+#include "mtk_auto_log.h"

+

+#ifdef LOG_TAG

+#undef LOG_TAG

+#define LOG_TAG "GFC_INF"

+#endif

+

+/**********************************************************

+ *  Define                                                *

+ **********************************************************/

+typedef void*(*threadptr)(void*);

+#define GEOFENCE_INJECT_LOC_ENUM 600

+

+#define MNLD_STRNCPY(dst,src,size) do{\

+                                       strncpy((char *)(dst), (src), (size - 1));\

+                                      (dst)[size - 1] = '\0';\

+                                     }while(0)

+

+

+/**********************************************************

+ *  Global Variables                                      *

+ **********************************************************/

+static MTK_GEOFENCE_PROPERTY_T geofence_property[MAX_GOEFENCE];

+static float injectFenceInfo[MAX_GOEFENCE][3];

+static int gTotalFence = 0; /*current fence number, must < MAX_GEOFENCE*/

+static int  g_ThreadExitGfcJniSocket = 0, isgfc_exist = 0;

+static pthread_t geofence_hal_jni_thread_id;

+static char g_gfc2mnl_path[128] = GEOFENCE_TO_MNL;

+int  g_gfc_server_socket_fd;

+unsigned int gConfigHalGeofence = 0;

+

+/**********************************************************

+ *  Function Declaration                                  *

+ **********************************************************/

+void mnl2gfchal_jni_thread(void);

+

+

+/**********************************************************

+ *  Socket Function                                       *

+ **********************************************************/

+static int safe_recvfrom(int sockfd, char* buf, int len) {

+    int ret = 0;

+    int retry = 10;

+

+    while ((ret = recvfrom(sockfd, buf, len, 0, NULL, NULL)) == -1) {

+        //LOGW("ret=%d len=%d\n", ret, len);

+        if (errno == EINTR) continue;

+        if (errno == EAGAIN) {

+            if (retry-- > 0) {

+                usleep(100 * 1000);

+                continue;

+            }

+        }

+        LOGE("sendto reason=[%s]\n", strerror(errno));

+        break;

+    }

+    return ret;

+}

+

+// -1 means failure

+static int safe_sendto(int sockfd, const char* dest, const char* buf, int size) {

+    int len = 0;

+    struct sockaddr_un soc_addr;

+    int retry = 10;

+

+    memset(&soc_addr, 0, sizeof(soc_addr));

+    soc_addr.sun_path[0] = 0;

+    MNLD_STRNCPY(soc_addr.sun_path + 1, dest,sizeof(soc_addr.sun_path) - 1);

+    soc_addr.sun_family = AF_UNIX;

+

+    while ((len = sendto(sockfd, buf, size, 0, (const struct sockaddr *)&soc_addr, sizeof(soc_addr))) == -1) {

+        if (errno == EINTR) continue;

+        if (errno == EAGAIN) {

+            if (retry-- > 0) {

+                usleep(100 * 1000);

+                continue;

+            }

+        }

+        LOGE("sendto dest=[%s] len=%d reason=[%s]\n",dest, size, strerror(errno));

+        break;

+    }

+    return len;

+}

+

+static int gfc_send2mnl(const char* buff, int len) {

+    int ret = 0;

+    int sockfd = socket(PF_LOCAL, SOCK_DGRAM, 0);

+

+    if (sockfd < 0) {

+        LOGE("gfc_send2mnl() socket() failed reason=[%s]%d",

+            strerror(errno), errno);

+        return -1;

+    }

+

+    if (safe_sendto(sockfd, g_gfc2mnl_path, buff, len) < 0) {

+        LOGE("gfc_send2mnl safe_sendto failed\n");

+        ret = -1;

+    }

+    close(sockfd);

+    return ret;

+}

+

+static int bind_udp_socket(char* path) {

+    int sockfd;

+    struct sockaddr_un soc_addr;

+

+    sockfd = socket(PF_LOCAL, SOCK_DGRAM, 0);

+    if (sockfd < 0) {

+        LOGE("socket failed reason=[%s]\n", strerror(errno));

+        return -1;

+    }

+    memset(&soc_addr, 0, sizeof(soc_addr));

+    soc_addr.sun_path[0] = 0;

+    MNLD_STRNCPY(soc_addr.sun_path + 1, path,sizeof(soc_addr.sun_path) - 1);

+    soc_addr.sun_family = AF_UNIX;

+    unlink(soc_addr.sun_path);

+

+    if (bind(sockfd, (struct sockaddr *)&soc_addr, sizeof(soc_addr)) < 0) {

+        LOGE("bind failed path=[%s] reason=[%s]\n", path, strerror(errno));

+        close(sockfd);

+        return -1;

+    }

+

+    return sockfd;

+}

+

+

+/**********************************************************

+ *  Geofence sub-Functions                                *

+ **********************************************************/

+static void set_buff_init_fence() {

+    int i;

+    memset(&geofence_property, 0, MAX_GOEFENCE*sizeof(MTK_GEOFENCE_PROPERTY_T));

+    for(i = 0; i < MAX_GOEFENCE; i++) {

+        geofence_property[i].geofence_id = -1;

+    }

+    gTotalFence = 0;

+    return;

+}

+

+static int set_buff_pause_fence(const int item) {

+    geofence_property[item].alive = 0;

+    geofence_property[item].last_transition = GPS_GEOFENCE_UNCERTAIN;

+    geofence_property[item].latest_state = uncertain;

+    return MTK_GFC_SUCCESS;

+}

+

+static int set_buff_resume_fence(const int item, const int transition) {

+    geofence_property[item].monitor_transition = transition;

+    geofence_property[item].alive = 1;

+    return MTK_GFC_SUCCESS;

+}

+

+static int set_buff_remove_fence(const int item) {

+    geofence_property[item].alive = 0;

+    memset(&geofence_property[item],0,sizeof(MTK_GEOFENCE_PROPERTY_T));

+    geofence_property[item].geofence_id = -1;

+    if(gTotalFence > 0) {

+        gTotalFence--;

+    }

+    return MTK_GFC_SUCCESS;

+}

+

+int set_buff_transition_fence(const int32_t fence_id, const int transition) {

+    int item;

+

+    if (transition != GPS_GEOFENCE_ENTERED &&

+        transition != GPS_GEOFENCE_EXITED &&

+        transition != GPS_GEOFENCE_UNCERTAIN) {

+        LOGE("transition type is invalid %d", transition);

+        return MTK_GFC_ERROR;

+    }

+

+    item = check_buff_fence_exist(fence_id);

+    if (item < 0) {

+        LOGE("transition fence id not exist");

+        return MTK_GFC_ERROR;

+    }

+    geofence_property[item].last_transition = transition;

+    geofence_property[item].latest_state = transition >> 1;

+    return MTK_GFC_SUCCESS;

+}

+

+void mtk_geo_inject_info_init() {

+    memset(injectFenceInfo, 0, sizeof(injectFenceInfo[0][0]) * MAX_GOEFENCE * 3);

+    //LOGD("GEO_JNI: init fence info\n");

+}

+

+static void mtk_geo_set_project_config() {

+    const char flp_prop_path[] = "/vendor/etc/geo.prop";

+    char propbuf[512];

+    FILE *fp = fopen(flp_prop_path, "rb");

+

+    gConfigHalGeofence = 0;

+    if(!fp) {

+        LOGE("mtk_flp_set_project_config - open fd fail! %d (%s)", errno, strerror(errno));

+        return;

+    }

+    while(fgets(propbuf, sizeof(propbuf), fp)) {

+        if(strstr(propbuf, "lowpower.geofence=no")) {

+            gConfigHalGeofence |= GEO_CONFIG_MASK_DISABLE_SMD;

+        }

+    }

+    LOGD("mtk_flp_set_project_config %u", gConfigHalGeofence);

+    fclose(fp);

+    return;

+}

+

+void mtk_geo_inject_info_set(int fence_id, float dn, float de) {

+    if (fence_id < MAX_GOEFENCE) {

+        injectFenceInfo[fence_id][0] = 1; //valid

+        injectFenceInfo[fence_id][1] = dn;

+        injectFenceInfo[fence_id][2] = de;

+        LOGD("GEO_JNI :set fence info, %d %f %f", fence_id, dn, de);

+    }

+}

+

+void mtk_geo_inject_info_reset(int fence_id) {

+    if (fence_id < MAX_GOEFENCE) {

+        injectFenceInfo[fence_id][0] = 0; //valid

+        injectFenceInfo[fence_id][1] = 0;

+        injectFenceInfo[fence_id][2] = 0;

+        LOGD("GEO_JNI: reset fence id %d\n", fence_id);

+    }

+}

+

+void mtk_geo_inject_info_get(int fence_id, float* dn, float* de) {

+    *dn = 0;

+    *de = 0;

+    if (fence_id < MAX_GOEFENCE) {

+        if (injectFenceInfo[fence_id][0]) {

+            *dn = injectFenceInfo[fence_id][1];

+            *de = injectFenceInfo[fence_id][2];

+            LOGD("GEO_JNI: get fence info %d %f %f\n", fence_id, *dn, *de);

+        }

+    }

+}

+

+static int check_buff_full_of_fence() {

+    if(gTotalFence >= MAX_GOEFENCE) {

+        return MTK_GFC_ERROR;

+    } else {

+        return MTK_GFC_SUCCESS;

+    }

+}

+

+int check_buff_fence_exist(const int32_t fence_id) {

+    int i;

+

+    for(i = 0; i < MAX_GOEFENCE; i++) {

+        if(geofence_property[i].geofence_id == fence_id ) {

+            return i;

+        }

+    }

+    return MTK_GFC_ERROR;

+}

+

+static int check_valid_transition(const int transition) {

+    switch(transition) {

+        case GPS_GEOFENCE_ENTERED:

+        case GPS_GEOFENCE_EXITED:

+        case GPS_GEOFENCE_ENTERED|GPS_GEOFENCE_EXITED:

+        case GPS_GEOFENCE_ENTERED|GPS_GEOFENCE_EXITED|GPS_GEOFENCE_UNCERTAIN:

+            return MTK_GFC_SUCCESS;

+        default:

+            return MTK_GFC_ERROR;

+    }

+}

+

+static int get_buff_avalibale_item() {

+    int i = 0;

+

+    while(i < MAX_GOEFENCE && geofence_property[i].alive == 1) {

+        i++;

+    }

+

+    if(i == MAX_GOEFENCE) {

+        return MTK_GFC_ERROR;

+    }

+    return i;

+}

+

+static int check_fence_vadility(const MTK_GEOFENCE_PROPERTY_T fence) {

+    int ret;

+    int ret2;

+

+    ret = check_buff_full_of_fence();

+    if(ret < 0) {

+        LOGE("too many fences\n");

+        ret2 =  -1;

+        return ret2;

+    }

+    ret = check_buff_fence_exist(fence.geofence_id);

+    if(ret >= 0) {

+        LOGE("fence has been added before\n");

+        ret2 =  -2;

+        return ret2;

+    }

+    ret = check_valid_transition(fence.monitor_transition);

+    if(ret < 0) {

+        LOGE("fence is invalid\n");

+        ret2 =  -3;

+        return ret2;

+    }

+    ret2 = 0;

+    return ret2;

+}

+

+static int set_buff_add_fence(const MTK_GEOFENCE_PROPERTY_T fence) {

+    int item;

+

+    item = get_buff_avalibale_item();

+    if(item < 0) {

+        LOGE("out of range\n");

+        return MTK_GFC_ERROR;

+    }

+    //LOGD("new fenece will be added into item %d\n", item);

+

+    memcpy(&geofence_property[item], &fence, sizeof(MTK_GEOFENCE_PROPERTY_T));

+    geofence_property[item].alive = 1;

+    gTotalFence++;

+    return MTK_GFC_SUCCESS;

+}

+

+#ifdef MTK_64_PLATFORM

+void mtk_loc_rearrange(unsigned char *loc_in, GpsLocation *loc_out) {

+    unsigned char ratio = 2; //32 to 64-bits

+    unsigned char padding_diff = 4;

+    unsigned int sizeof_loc_in = sizeof(GpsLocation) - sizeof(size_t)/ratio - padding_diff;

+

+    memset(loc_out, 0, sizeof(GpsLocation));

+    loc_out->size = sizeof(GpsLocation);

+    memcpy(&loc_out->flags, loc_in + sizeof(size_t)/ratio, sizeof(uint16_t));

+    memcpy(&loc_out->latitude, loc_in + sizeof(size_t), sizeof_loc_in - sizeof(size_t));

+}

+#endif

+

+/*************************************************************/

+/*  mnl to FLP HAL socket, -1 means failure                  */

+/*************************************************************/

+int create_mnl2gfchal_fd() {

+    int fd = bind_udp_socket(MNL_TO_GEOFENCE);

+    return fd;

+}

+

+int is_gfc_exist() {

+    return isgfc_exist;

+}

+

+

+/*********************************************************/

+/* GPS Geofence Interface implementation                 */

+/*********************************************************/

+void hal2_geofence_init() {

+    int  ret;

+    #if 0

+    int offset = 0;

+    char buff[HAL_GFC_BUFF_SIZE] = {0};

+    MTK_FLP_MSG_T *geo_header =NULL;

+    MTK_FLP_MSG_T geo_msg;

+    #endif

+

+    //Init client socket thread

+    if(isgfc_exist) {

+        LOGE("geofence init before");

+        return;

+    }

+    ret = pthread_create(&geofence_hal_jni_thread_id, NULL, (threadptr)mnl2gfchal_jni_thread, NULL);

+    if(ret < 0) {

+        LOGE("Create mnl2gfchal_jni_thread error\n");

+    }

+    isgfc_exist = 1;

+    #if 0

+    geo_header = malloc(sizeof(MTK_FLP_MSG_T) + sizeof(MTK_FLP_MSG_T));

+    if(geo_header == NULL) {

+        LOGE("init fence malloc error");

+        return;

+    }

+

+    geo_header->type = MTK_FLP_MSG_OFL_GEOFENCE_CMD;

+    geo_header->length = sizeof(MTK_FLP_MSG_T) + sizeof(MTK_FLP_MSG_T);

+    geo_msg.type = INIT_GEOFENCE;

+    geo_msg.length = sizeof(MTK_FLP_MSG_T);

+    memcpy( ((char*)geo_header)+sizeof(MTK_FLP_MSG_T),&geo_msg, sizeof(MTK_FLP_MSG_T));

+    put_binary(buff, &offset, (const char*)&geo_header, geo_header->length);

+    ret = gfc_send2mnl(buff, offset);

+    free(geo_header);

+    if(ret < 0) {

+        LOGE("MTK_HAL2GFC send error return error");

+        return;

+    }

+    #endif

+    set_buff_init_fence();

+    mtk_geo_inject_info_init();

+    mtk_geo_set_project_config();

+    return;

+}

+

+void hal2_geofence_add_geofences(const MTK_GEOFENCE_PROPERTY_T dbg_fence) {

+    int ret, offset = 0;

+    char buff[HAL_GFC_BUFF_SIZE] = {0};

+    int32_t partial_size = 1;

+    MTK_FLP_MSG_T *geo_header=NULL;

+    MTK_FLP_MSG_T geo_msg;

+

+    /* For geofence recover mechanism */

+    ret = check_fence_vadility(dbg_fence);

+    if (ret == 0) {

+        set_buff_add_fence(dbg_fence);

+    } else {

+        return;

+    }

+

+    //construct add fence cmd

+    geo_header = malloc(2*sizeof(MTK_FLP_MSG_T)+sizeof(int32_t) + sizeof(MTK_GEOFENCE_PROPERTY_T));

+    if(geo_header == NULL) {

+        LOGE("add fence malloc error");

+        return;

+    }

+

+    geo_header->type = MTK_FLP_MSG_OFL_GEOFENCE_CMD;

+    geo_header->length = sizeof(MTK_FLP_MSG_T) + sizeof(MTK_FLP_MSG_T) + sizeof(int32_t) + sizeof(MTK_GEOFENCE_PROPERTY_T);

+    geo_msg.type = ADD_GEOFENCE_AREA;

+    geo_msg.length =  sizeof(MTK_FLP_MSG_T) + sizeof(int32_t) + sizeof(MTK_GEOFENCE_PROPERTY_T);

+    memcpy( ((char*)geo_header)+sizeof(MTK_FLP_MSG_T),&geo_msg, sizeof(MTK_FLP_MSG_T));

+    memcpy( ((char*)geo_header)+2*sizeof(MTK_FLP_MSG_T),&partial_size, sizeof(int32_t));

+    memcpy( ((char*)geo_header)+2*sizeof(MTK_FLP_MSG_T)+sizeof(int32_t),&dbg_fence, sizeof(MTK_GEOFENCE_PROPERTY_T));

+    #if 1

+    LOGD("HAL Add fence, id=%d, ll=%lf,%lf, last=%d, monitor=%d, notsec=%d, unksec=%d, ned=%f,%f, con=%u",

+        dbg_fence.geofence_id, dbg_fence.latitude, dbg_fence.longitude,

+        dbg_fence.last_transition, dbg_fence.monitor_transition,

+        dbg_fence.notification_period, dbg_fence.unknown_timer,

+        dbg_fence.coordinate_dn, dbg_fence.coordinate_de, dbg_fence.config);

+    #endif

+    put_binary(buff, &offset, (const char*)geo_header, geo_header->length);

+    ret = gfc_send2mnl(buff, offset);

+    free(geo_header);

+    if(ret < 0) {

+        LOGE("MTK_HAL2GFC send error return error");

+        return;

+    }

+    return;

+}

+

+void hal2_geofence_pause_geofence(const int32_t geofence_id) {

+    int ret, offset = 0;

+    char buff[HAL_GFC_BUFF_SIZE] = {0};

+    MTK_FLP_MSG_T *geo_header=NULL;

+    MTK_FLP_MSG_T geo_msg;

+

+    /* For geofence recover mechanism */

+    ret = check_buff_fence_exist(geofence_id);

+    if (ret != MTK_GFC_ERROR) {

+        set_buff_pause_fence(ret);

+    } else {

+        return;

+    }

+

+    //LOGD("hal2_geofence_pause_geofence, id: %d fence",geofence_id);

+    //construct pause fence cmd

+    geo_header = malloc(2*sizeof(MTK_FLP_MSG_T) + sizeof(int32_t));

+    if(geo_header == NULL) {

+        LOGE("pause fence malloc error");

+        return;

+    }

+

+    geo_header->type = MTK_FLP_MSG_OFL_GEOFENCE_CMD;

+    geo_header->length = sizeof(MTK_FLP_MSG_T) + sizeof(MTK_FLP_MSG_T) + sizeof(int32_t);

+    geo_msg.type = PAUSE_GEOFENCE;

+    geo_msg.length = sizeof(MTK_FLP_MSG_T) + sizeof(int32_t);

+    memcpy( ((char*)geo_header)+sizeof(MTK_FLP_MSG_T),&geo_msg, sizeof(MTK_FLP_MSG_T));

+    memcpy( ((char*)geo_header)+2*sizeof(MTK_FLP_MSG_T),&geofence_id, sizeof(int32_t));

+    put_binary(buff, &offset, (const char*)geo_header, geo_header->length);

+    ret = gfc_send2mnl(buff, offset);

+    free(geo_header);

+    if(ret < 0) {

+        LOGD("MTK_HAL2GFC send error return error");

+        return;

+    }

+    return;

+}

+

+

+void hal2_geofence_resume_geofence(const int32_t geofence_id, const int monitor_transitions) {

+    int ret, offset = 0;

+    char buff[HAL_GFC_BUFF_SIZE] = {0};

+    MTK_FLP_MSG_T *geo_header=NULL;

+    MTK_FLP_MSG_T geo_msg;

+

+    /* For geofence recover mechanism */

+    ret = check_buff_fence_exist(geofence_id);

+    if(ret != MTK_GFC_ERROR) {

+        set_buff_resume_fence(ret, monitor_transitions);

+    } else {

+        return;

+    }

+

+    //LOGD("hal2_geofence_resume_geofence, id: %d fence",geofence_id);

+    //construct resume fence cmd

+    geo_header = malloc(2*sizeof(MTK_FLP_MSG_T) + sizeof(int32_t) + sizeof(int));

+    if(geo_header == NULL) {

+        LOGE("resume fence malloc error");

+        return;

+    }

+    geo_header->type = MTK_FLP_MSG_OFL_GEOFENCE_CMD;

+    geo_header->length = 2*sizeof(MTK_FLP_MSG_T) + sizeof(int32_t) + sizeof(int);

+    geo_msg.type = RESUME_GEOFENCE;

+    geo_msg.length =  sizeof(MTK_FLP_MSG_T) + sizeof(int32_t) + sizeof(int);

+    memcpy( ((char*)geo_header)+sizeof(MTK_FLP_MSG_T),&geo_msg, sizeof(MTK_FLP_MSG_T));

+    memcpy( ((char*)geo_header)+2*sizeof(MTK_FLP_MSG_T),&geofence_id, sizeof(int32_t));

+    memcpy( ((char*)geo_header)+2*sizeof(MTK_FLP_MSG_T)+sizeof(int32_t),&monitor_transitions, sizeof(int));

+    put_binary(buff, &offset, (const char*)geo_header, geo_header->length);

+    ret = gfc_send2mnl(buff, offset);

+    free(geo_header);

+    if(ret < 0) {

+        LOGE("MTK_HAL2GFC send error return error");

+        return;

+    }

+    return;

+}

+

+void hal2_geofence_remove_geofences(const int32_t geofence_id) {

+    int ret, offset = 0;

+    char buff[HAL_GFC_BUFF_SIZE] = {0};

+    MTK_FLP_MSG_T *geo_header=NULL;

+    MTK_FLP_MSG_T geo_msg;

+

+    /* For geofence recover mechanism */

+    ret = check_buff_fence_exist(geofence_id);

+    if(ret != MTK_GFC_ERROR) {

+        mtk_geo_inject_info_reset(geofence_id);

+        set_buff_remove_fence(ret);

+    } else {

+        return;

+    }

+

+    //LOGD("hal2_geofence_remove_geofences, fence id =%d",geofence_id);

+    //construct remove fence cmd

+    geo_header = malloc(2*sizeof(MTK_FLP_MSG_T) + sizeof(int32_t));

+    if(geo_header == NULL) {

+        LOGE("resume fence malloc error");

+        return;

+    }

+

+    geo_header->type = MTK_FLP_MSG_OFL_GEOFENCE_CMD;

+    geo_header->length = sizeof(MTK_FLP_MSG_T) + sizeof(MTK_FLP_MSG_T) + sizeof(int32_t);

+    geo_msg.type = REMOVE_GEOFENCE;

+    geo_msg.length = sizeof(MTK_FLP_MSG_T) + sizeof(int32_t);

+    memcpy( ((char*)geo_header)+sizeof(MTK_FLP_MSG_T),&geo_msg, sizeof(MTK_FLP_MSG_T));

+    memcpy( ((char*)geo_header)+2*sizeof(MTK_FLP_MSG_T),&geofence_id, sizeof(int32_t));

+    put_binary(buff, &offset, (const char*)geo_header, geo_header->length);

+    ret = gfc_send2mnl(buff, offset);

+    free(geo_header);

+    if(ret < 0) {

+        LOGE("MTK_HAL2GFC send error return error");

+        return;

+    }

+    return;

+}

+

+void hal2_geofence_recover_geofences() {

+    int ret, offset = 0;

+    char buff[HAL_GFC_BUFF_SIZE] = {0};

+    int i;

+    int partial_size = 1;

+    MTK_FLP_MSG_T* geo_header = NULL;

+    MTK_FLP_MSG_T geo_msg;

+

+    LOGE("FLP HAL RECOVER: recover total fence = %d", gTotalFence);

+    for(i = 0; i < MAX_GOEFENCE; i++) {

+        if(geofence_property[i].alive == 1) {

+            geo_header = malloc( sizeof(MTK_FLP_MSG_T)+ sizeof(MTK_FLP_MSG_T) + sizeof(int32_t) + sizeof(MTK_GEOFENCE_PROPERTY_T));

+            geo_header->type = MTK_FLP_MSG_OFL_GEOFENCE_CMD;

+            geo_header->length =  sizeof(MTK_FLP_MSG_T)+ sizeof(MTK_FLP_MSG_T)+ sizeof(int32_t) + sizeof(MTK_GEOFENCE_PROPERTY_T);

+            geo_msg.type = RECOVER_GEOFENCE;

+            geo_msg.length =  sizeof(MTK_FLP_MSG_T)+ sizeof(int32_t) + sizeof(MTK_GEOFENCE_PROPERTY_T);

+            memcpy(((char*)geo_header)+sizeof(MTK_FLP_MSG_T), &geo_msg, sizeof(MTK_FLP_MSG_T));

+            memcpy((((char*)geo_header)+sizeof(MTK_FLP_MSG_T)+sizeof(MTK_FLP_MSG_T)), &partial_size, sizeof(int32_t));

+            memcpy((((char*)geo_header)+sizeof(MTK_FLP_MSG_T)+sizeof(MTK_FLP_MSG_T)+sizeof(int32_t)),&geofence_property[i],sizeof(MTK_GEOFENCE_PROPERTY_T));

+            LOGE("FLP HAL RECOVER: id=%"PRId32",type=%d,%d,%d,%lf,%d",geofence_property[i].geofence_id,geofence_property[i].last_transition,geofence_property[i].monitor_transition,

+            geofence_property[i].notification_period,geofence_property[i].latitude,geofence_property[i].unknown_timer);

+            offset = 0;

+            put_binary(buff, &offset, (const char*)geo_header, geo_header->length);

+            ret = gfc_send2mnl(buff, offset);

+            free(geo_header);

+            if(ret < 0) {

+                LOGE("MTK_HAL2GFC send error return error");

+                return;

+            }

+        }

+    }

+    return;

+}

+

+int mnl2gfchal_hdlr (char *buff) {

+    char data[1024] = {0};

+    int offset = 0;

+    int ret = MTK_GFC_ERROR, len;

+    unsigned int cmd, msg_len;

+    float geo_inject[3] = {0};

+    MTK_FLP_MSG_T *prmsg = NULL;

+

+    if(buff == NULL) {

+        LOGE("mnl2gfchal_hdlr, recv prmsg is null pointer\r\n");

+        return MTK_GFC_ERROR;

+    }

+    len = get_binary(buff, &offset, data, HAL_GFC_BUFF_SIZE, sizeof(data));

+    if((len > 0) && (len<=1024)) {

+        prmsg = (MTK_FLP_MSG_T *)&data[0];

+    } else {

+        LOGE("len err:%d",len);

+        return ret;

+    }

+    cmd = prmsg->type;

+    msg_len = prmsg->length;

+

+    LOGD("msg_len, recv prmsg, type %d, len %d\r\n", cmd, msg_len);

+    switch (cmd) {

+        case MTK_FLP_MSG_SYS_FLPD_RESET_NTF:

+            hal2_geofence_recover_geofences();

+            break;

+        case MTK_FLP_MSG_OFL_GEOFENCE_CALLBACK_NTF:

+            mtk_geofence_transition_callbacks_proc(prmsg);

+            break;

+        case MTK_FLP_MSG_HAL_GEOFENCE_CALLBACK_NTF:

+            mtk_geofence_callbacks_proc(prmsg);

+            break;

+        case GEOFENCE_INJECT_LOC_ENUM:

+            if(msg_len< 3*sizeof(float)) {

+                LOGE("GEOFENCE_INJECT_LOC_ENUM incrorrect size %d",msg_len);

+                return MTK_GFC_ERROR;

+            }

+            memcpy(geo_inject, (char *)prmsg + sizeof(MTK_FLP_MSG_T), 3*sizeof(float));

+            mtk_geo_inject_info_set((int)geo_inject[0],geo_inject[1],geo_inject[2]);

+            break;

+        default:

+            LOGE("invalid geofence cmd:0x%02x",cmd);

+            break;

+    }

+    return MTK_GFC_SUCCESS;

+}

+

+

+/*************************************************************/

+/*  mnl to GPS/Geofence HAL main thread                      */

+/*************************************************************/

+void mnl2gfchal_jni_thread(void) {

+

+    int ret = MTK_GFC_SUCCESS;

+    int offset = 0;

+    int read_len;

+    char buff[HAL_GFC_BUFF_SIZE] = {0};

+    MTK_FLP_MSG_T gfc_header;

+

+    LOGD("mtk_gfc_hal_jni_thread, Create\n");

+

+    g_gfc_server_socket_fd = create_mnl2gfchal_fd();

+

+    ///TODO: add system timer function here

+    //mtk_flp_sys_timer_create(FLP_TIMER_ID_CHECKCNN);

+    //Send SYS_INIT to HAL

+    gfc_header.type = MTK_FLP_MSG_HAL_INIT_CMD;

+    gfc_header.length = 0;

+    put_binary(buff, &offset, (const char*)&gfc_header, sizeof(MTK_FLP_MSG_T));

+    ret = gfc_send2mnl(buff, offset);

+    //LOGD("gfc:MTK_FLP_MSG_HAL_INIT_CMD");

+    if(ret < 0) {

+        LOGE("MTK_HAL2GFC send error return error");

+    }

+

+    if (g_gfc_server_socket_fd >= 0) {

+        while(!g_ThreadExitGfcJniSocket) {

+            // - recv msg from socket interface

+            read_len = safe_recvfrom(g_gfc_server_socket_fd, buff, sizeof(buff));

+            if ((read_len <= 0) || (read_len>HAL_GFC_BUFF_SIZE)) {

+                LOGE("mnl2gfc safe_recvfrom failed read_len=%d", read_len);

+            }

+

+            if (!g_ThreadExitGfcJniSocket) {

+                // Process received message

+                mnl2gfchal_hdlr(buff);

+            } else {

+                LOGE("mtk_flp_hal_jni_thread, read msg fail,exit socket thread\n");

+                //read msg fail...

+                g_ThreadExitGfcJniSocket = 1;

+            }

+        }

+    }

+

+    //close socket

+    LOGD("Closing server_fd,%d\r\n",g_gfc_server_socket_fd);

+    if(g_gfc_server_socket_fd >= 0) {

+        close(g_gfc_server_socket_fd);

+    }

+

+    LOGD("mnl2gfchal_jni_thread, exit\n");

+

+    g_ThreadExitGfcJniSocket = 1;

+    pthread_exit(NULL);

+

+    return;

+}

+

+

diff --git a/src/connectivity/gps/gps_hal/src/gpshal.c b/src/connectivity/gps/gps_hal/src/gpshal.c
new file mode 100644
index 0000000..41ac6a9
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/src/gpshal.c
@@ -0,0 +1,221 @@
+/* Copyright Statement:
+ *
+ * This software/firmware and related documentation ("MediaTek Software") are
+ * protected under relevant copyright laws. The information contained herein
+ * is confidential and proprietary to MediaTek Inc. and/or its licensors.
+ * Without the prior written permission of MediaTek inc. and/or its licensors,
+ * any reproduction, modification, use or disclosure of MediaTek Software,
+ * and information contained herein, in whole or in part, shall be strictly prohibited.
+ *
+ * MediaTek Inc. (C) 2016. All rights reserved.
+ *
+ * BY OPENING THIS FILE, RECEIVER HEREBY UNEQUIVOCALLY ACKNOWLEDGES AND AGREES
+ * THAT THE SOFTWARE/FIRMWARE AND ITS DOCUMENTATIONS ("MEDIATEK SOFTWARE")
+ * RECEIVED FROM MEDIATEK AND/OR ITS REPRESENTATIVES ARE PROVIDED TO RECEIVER ON
+ * AN "AS-IS" BASIS ONLY. MEDIATEK EXPRESSLY DISCLAIMS ANY AND ALL WARRANTIES,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NONINFRINGEMENT.
+ * NEITHER DOES MEDIATEK PROVIDE ANY WARRANTY WHATSOEVER WITH RESPECT TO THE
+ * SOFTWARE OF ANY THIRD PARTY WHICH MAY BE USED BY, INCORPORATED IN, OR
+ * SUPPLIED WITH THE MEDIATEK SOFTWARE, AND RECEIVER AGREES TO LOOK ONLY TO SUCH
+ * THIRD PARTY FOR ANY WARRANTY CLAIM RELATING THERETO. RECEIVER EXPRESSLY ACKNOWLEDGES
+ * THAT IT IS RECEIVER'S SOLE RESPONSIBILITY TO OBTAIN FROM ANY THIRD PARTY ALL PROPER LICENSES
+ * CONTAINED IN MEDIATEK SOFTWARE. MEDIATEK SHALL ALSO NOT BE RESPONSIBLE FOR ANY MEDIATEK
+ * SOFTWARE RELEASES MADE TO RECEIVER'S SPECIFICATION OR TO CONFORM TO A PARTICULAR
+ * STANDARD OR OPEN FORUM. RECEIVER'S SOLE AND EXCLUSIVE REMEDY AND MEDIATEK'S ENTIRE AND
+ * CUMULATIVE LIABILITY WITH RESPECT TO THE MEDIATEK SOFTWARE RELEASED HEREUNDER WILL BE,
+ * AT MEDIATEK'S OPTION, TO REVISE OR REPLACE THE MEDIATEK SOFTWARE AT ISSUE,
+ * OR REFUND ANY SOFTWARE LICENSE FEES OR SERVICE CHARGE PAID BY RECEIVER TO
+ * MEDIATEK FOR SUCH MEDIATEK SOFTWARE AT ISSUE.
+ *
+ * The following software/firmware and/or related documentation ("MediaTek Software")
+ * have been modified by MediaTek Inc. All revisions are subject to any receiver's
+ * applicable license agreements with MediaTek Inc.
+ */
+#include "gpshal.h"
+#include <sys/epoll.h>  // epoll_create, epoll_event
+#include <errno.h>     // errno
+#include <string.h>    // strerror
+
+#include "hal2mnl_interface.h"
+#include "mtk_lbs_utility.h"
+#include "gpshal_param_check.h"
+#include "mtk_auto_log.h"
+
+#if ANDROID_MNLD_PROP_SUPPORT
+#include <cutils/properties.h>
+#endif
+
+#ifdef LOG_TAG
+#undef LOG_TAG
+#define LOG_TAG "gpshal"
+#endif
+
+#define GPSHAL_WORKER_THREAD_NAME "gpshal_worker_thread"
+
+//=========================================================
+
+gpshal_context_t g_gpshal_ctx = {
+    .fd_mnl2hal        = -1,
+    .fd_worker_epoll   = -1,
+    .thd_worker        = 0,
+    .mutex_gps_state_intent = PTHREAD_MUTEX_INITIALIZER,
+    .gps_state_intent  = GPSHAL_STATE_UNKNOWN,
+    .gps_state         = GPSHAL_STATE_UNKNOWN,
+    .gps_cbs           = NULL,
+    .agps_cbs          = NULL,
+    .gpsni_cbs         = NULL,
+    .agpsril_cbs       = NULL,
+    .meas_cbs          = NULL,
+    .navimsg_cbs       = NULL,
+    .geofence_cbs      = NULL,
+    .vzw_debug_cbs     = NULL,
+};
+
+//=========================================================
+
+const char* gpshal_state_to_string(gpshal_state state) {
+    switch (state) {
+        case GPSHAL_STATE_UNKNOWN:  return "UNKNOWN";
+        case GPSHAL_STATE_RESOURCE: return "RESOURCE_INIT";
+        case GPSHAL_STATE_CLEANUP:  return "CLEANUP";
+        case GPSHAL_STATE_INIT:     return "INIT";
+        case GPSHAL_STATE_STOP:     return "STOP";
+        case GPSHAL_STATE_START:    return "START";
+        default:                    return "INVALID";
+    }
+}
+
+static void gpshal_set_gps_state(gpshal_state newState) {
+    /*LOGD("gps_state: %s -> %s (intent: %s)",
+            gpshal_state_to_string(g_gpshal_ctx.gps_state),
+            gpshal_state_to_string(newState),
+            gpshal_state_to_string(g_gpshal_ctx.gps_state_intent));*/
+    g_gpshal_ctx.gps_state = newState;
+}
+
+void gpshal_set_gps_state_intent(gpshal_state newState) {
+    /*LOGD("gps_state: %s (intent: %s -> %s)",
+            gpshal_state_to_string(g_gpshal_ctx.gps_state),
+            gpshal_state_to_string(g_gpshal_ctx.gps_state_intent),
+            gpshal_state_to_string(newState));*/
+    g_gpshal_ctx.gps_state_intent = newState;
+}
+
+static void gpshal_check_capability(unsigned int *capabilities, unsigned int *year) {
+    #if ANDROID_MNLD_PROP_SUPPORT
+    char chip_id[PROPERTY_VALUE_MAX]={0};
+    property_get("persist.vendor.connsys.chipid", chip_id, NULL);
+    #else
+    char chip_id[100]={0};
+    strncpy(chip_id, "0x6630",sizeof(chip_id));
+    #endif
+    LOGI("chip id = %s", chip_id);
+    if (strcmp(chip_id, "0x6739") == 0 || strcmp(chip_id, "0x6765") == 0 ||
+        strcmp(chip_id, "0x6761") == 0) {
+        /*our HIDL version is 1.0, if the year is 2018, CTS GnssHardwareInfoTest#testHardwareModelName will fail*/
+        //*year = 2018;
+        *year = 2017;
+        *capabilities = (GPS_CAP_MEASUREMENTS | GPS_CAP_MSB | GPS_CAP_MSA);
+    } else {
+        /*our HIDL version is 1.0, if the year is 2018, CTS GnssHardwareInfoTest#testHardwareModelName will fail*/
+        *year = 2017;
+        *capabilities = (GPS_CAP_MEASUREMENTS | GPS_CAP_MSB | GPS_CAP_MSA);
+    }
+}
+//=========================================================
+
+// Design policy
+//     Init resources at most once (no retry)
+//         Because we can not save an unstable system,
+//         we think "less system call is better" for an unstable system
+//     Do not deinit resources
+//         We want to have a simple design for a built-in service
+//         "Deinit" is for an installable / removable service
+static void gpshal_resource_init(GpsCallbacks_ext* src) {
+    unsigned int capabilities = 0;
+    unsigned int year = 0;
+    g_gpshal_ctx.gps_cbs = (GpsCallbacks_ext*)src;
+    if (GPSHAL_STATE_UNKNOWN != g_gpshal_ctx.gps_state_intent) return;  // at most once
+
+    gpshal_check_capability(&capabilities, &year);
+    LOGI("year = %d, capabilities = %d", year, capabilities);
+    g_gpshal_ctx.gps_cbs->set_capabilities_cb(capabilities);
+
+    GnssSystemInfo system_info;
+    system_info.year_of_hw = year;
+    system_info.size = sizeof(GnssSystemInfo);
+    g_gpshal_ctx.gps_cbs->set_system_info_cb(&system_info);
+
+    g_gpshal_ctx.fd_mnl2hal = create_mnl2hal_fd();
+    if (-1 == g_gpshal_ctx.fd_mnl2hal) return;  // error
+
+    g_gpshal_ctx.fd_worker_epoll = epoll_create(MAX_EPOLL_EVENT);
+    if (-1 == g_gpshal_ctx.fd_worker_epoll) {
+        LOGE("Fail to create epoll reason=[%s]%d",
+                strerror(errno), errno);
+        return;  // error
+    }
+
+    if (epoll_add_fd(
+            g_gpshal_ctx.fd_worker_epoll,
+            g_gpshal_ctx.fd_mnl2hal) == -1) {
+        LOGE("Fail to add fd_mnl2hal");
+        return;  // error
+    }
+
+    g_gpshal_ctx.thd_worker = g_gpshal_ctx.gps_cbs->create_thread_cb(
+            GPSHAL_WORKER_THREAD_NAME, gpshal_worker_thread, NULL);
+    if (!g_gpshal_ctx.thd_worker) {
+        LOGE("Fail to create %s", GPSHAL_WORKER_THREAD_NAME);
+        return;  // error
+    }
+
+    gpshal_set_gps_state(GPSHAL_STATE_RESOURCE);
+}
+
+int gpshal_gpscbs_save(GpsCallbacks_ext* src) {
+// assert(NULL != src);
+    if (sizeof(GpsCallbacks_ext) == src->size) {
+        LOGD("Use GpsCallbacks");
+        gpshal_resource_init(src);
+        return 0;
+    }
+    LOGE("Bad callback, size: %zd, expected: %zd",
+            src->size, sizeof(GpsCallbacks_ext));
+    return -1;    //  error
+}
+
+//=========================================================
+
+void gpshal2mnl_gps_init() {
+    if (GPSHAL_STATE_RESOURCE <= g_gpshal_ctx.gps_state) {  // Check this for unstable system
+        if (hal2mnl_gps_init() > 0) {
+            gpshal_set_gps_state(GPSHAL_STATE_INIT);
+        }
+    }
+}
+
+void gpshal2mnl_gps_start() {
+    if (GPSHAL_STATE_RESOURCE <= g_gpshal_ctx.gps_state) {
+        if (hal2mnl_gps_start() > 0) {
+            gpshal_set_gps_state(GPSHAL_STATE_START);
+        }
+    }
+}
+
+void gpshal2mnl_gps_stop() {
+    if (GPSHAL_STATE_RESOURCE <= g_gpshal_ctx.gps_state) {
+        if (hal2mnl_gps_stop() > 0) {
+            gpshal_set_gps_state(GPSHAL_STATE_STOP);
+        }
+    }
+}
+
+void gpshal2mnl_gps_cleanup() {
+    if (GPSHAL_STATE_RESOURCE <= g_gpshal_ctx.gps_state) {
+        if (hal2mnl_gps_cleanup() > 0) {
+            gpshal_set_gps_state(GPSHAL_STATE_CLEANUP);
+        }
+    }
+}
diff --git a/src/connectivity/gps/gps_hal/src/gpshal_worker.c b/src/connectivity/gps/gps_hal/src/gpshal_worker.c
new file mode 100644
index 0000000..e4012e5
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/src/gpshal_worker.c
@@ -0,0 +1,476 @@
+/* Copyright Statement:
+ *
+ * This software/firmware and related documentation ("MediaTek Software") are
+ * protected under relevant copyright laws. The information contained herein
+ * is confidential and proprietary to MediaTek Inc. and/or its licensors.
+ * Without the prior written permission of MediaTek inc. and/or its licensors,
+ * any reproduction, modification, use or disclosure of MediaTek Software,
+ * and information contained herein, in whole or in part, shall be strictly prohibited.
+ *
+ * MediaTek Inc. (C) 2016. All rights reserved.
+ *
+ * BY OPENING THIS FILE, RECEIVER HEREBY UNEQUIVOCALLY ACKNOWLEDGES AND AGREES
+ * THAT THE SOFTWARE/FIRMWARE AND ITS DOCUMENTATIONS ("MEDIATEK SOFTWARE")
+ * RECEIVED FROM MEDIATEK AND/OR ITS REPRESENTATIVES ARE PROVIDED TO RECEIVER ON
+ * AN "AS-IS" BASIS ONLY. MEDIATEK EXPRESSLY DISCLAIMS ANY AND ALL WARRANTIES,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NONINFRINGEMENT.
+ * NEITHER DOES MEDIATEK PROVIDE ANY WARRANTY WHATSOEVER WITH RESPECT TO THE
+ * SOFTWARE OF ANY THIRD PARTY WHICH MAY BE USED BY, INCORPORATED IN, OR
+ * SUPPLIED WITH THE MEDIATEK SOFTWARE, AND RECEIVER AGREES TO LOOK ONLY TO SUCH
+ * THIRD PARTY FOR ANY WARRANTY CLAIM RELATING THERETO. RECEIVER EXPRESSLY ACKNOWLEDGES
+ * THAT IT IS RECEIVER'S SOLE RESPONSIBILITY TO OBTAIN FROM ANY THIRD PARTY ALL PROPER LICENSES
+ * CONTAINED IN MEDIATEK SOFTWARE. MEDIATEK SHALL ALSO NOT BE RESPONSIBLE FOR ANY MEDIATEK
+ * SOFTWARE RELEASES MADE TO RECEIVER'S SPECIFICATION OR TO CONFORM TO A PARTICULAR
+ * STANDARD OR OPEN FORUM. RECEIVER'S SOLE AND EXCLUSIVE REMEDY AND MEDIATEK'S ENTIRE AND
+ * CUMULATIVE LIABILITY WITH RESPECT TO THE MEDIATEK SOFTWARE RELEASED HEREUNDER WILL BE,
+ * AT MEDIATEK'S OPTION, TO REVISE OR REPLACE THE MEDIATEK SOFTWARE AT ISSUE,
+ * OR REFUND ANY SOFTWARE LICENSE FEES OR SERVICE CHARGE PAID BY RECEIVER TO
+ * MEDIATEK FOR SUCH MEDIATEK SOFTWARE AT ISSUE.
+ *
+ * The following software/firmware and/or related documentation ("MediaTek Software")
+ * have been modified by MediaTek Inc. All revisions are subject to any receiver's
+ * applicable license agreements with MediaTek Inc.
+ */
+#include "gpshal.h"
+#include <sys/epoll.h>  // epoll_create, epoll_event
+#include <errno.h>     // errno
+#include <string.h>    // strerror
+// #include <linux/in.h>   // INADDR_NONE
+#include "hal2mnl_interface.h"
+#include "mtk_lbs_utility.h"
+#include "mtk_auto_log.h"
+
+#ifdef LOG_TAG
+#undef LOG_TAG
+#define LOG_TAG "gpshal_worker"
+#endif
+
+//=========================================================
+
+#define GPSHAL_WORKER_THREAD_TIMEOUT (30*1000)
+
+#define fieldp_copy(dst, src, f)  (dst)->f  = (src)->f
+#define field_copy(dst, src, f)  (dst).f   = (src).f
+
+DebugData mnlDebugData; //for GNSS HIDL v1.1 GPS debug interface
+
+//=========================================================
+
+static void update_mnld_reboot() {
+// GPSHAL_DEBUG_FUNC_SCOPE2(g_gpshal_ctx.mutex_gps_state_intent);
+    gpshal_state state = g_gpshal_ctx.gps_state_intent;
+    LOGD("state: (%d)", state);
+    switch (state) {
+        case GPSHAL_STATE_INIT:
+        case GPSHAL_STATE_STOP:
+            gpshal2mnl_gps_init();
+            break;
+        case GPSHAL_STATE_START:
+            gpshal2mnl_gps_init();
+            gpshal2mnl_gps_start();
+            break;
+        case GPSHAL_STATE_CLEANUP:
+        default:
+            LOGW("Current gps_state_intent: %s (%d)",
+                gpshal_state_to_string(state), state);
+    }
+}
+static void update_location(gps_location location) {
+    // Use mutex or not ?
+    //     If no, the issue may occur.
+    //     If yes, there will be a little performance impact.
+  //  GPSHAL_DEBUG_FUNC_SCOPE;
+    GpsLocation_ext loc;
+    //dump_gps_location(location);
+    gpshal_state state = g_gpshal_ctx.gps_state;
+    //LOGD("state: (%d)", state);
+    if (GPSHAL_STATE_START == state) {
+         loc.legacyLocation.size      = sizeof(loc);
+         loc.legacyLocation.flags     = location.flags;
+         loc.legacyLocation.latitude  = location.lat;
+         loc.legacyLocation.longitude = location.lng;
+         loc.legacyLocation.altitude  = location.alt;
+         loc.legacyLocation.speed     = location.speed;
+         loc.legacyLocation.bearing   = location.bearing;
+         loc.legacyLocation.accuracy  = loc.horizontalAccuracyMeters = location.h_accuracy;
+         loc.verticalAccuracyMeters       = location.v_accuracy;
+         loc.speedAccuracyMetersPerSecond = location.s_accuracy;
+         loc.bearingAccuracyDegrees       = location.b_accuracy;
+         loc.legacyLocation.timestamp = location.timestamp;
+         LOGD("hacc=%f,vacc=%f,sacc=%f,bacc=%f", loc.horizontalAccuracyMeters, loc.verticalAccuracyMeters,
+             loc.speedAccuracyMetersPerSecond, loc.bearingAccuracyDegrees);
+         g_gpshal_ctx.gps_cbs->location_cb(&loc);
+         //For GNSS HIDL v1.1 Gps debug interface
+         mnlDebugData.position.valid = true;
+         mnlDebugData.position.latitudeDegrees   = location.lat;
+         mnlDebugData.position.longitudeDegrees  = location.lng;
+         mnlDebugData.position.altitudeMeters    = location.alt;
+         mnlDebugData.position.speedMetersPerSec = location.speed;
+         mnlDebugData.position.bearingDegrees    = location.bearing;
+         mnlDebugData.position.horizontalAccuracyMeters     = location.h_accuracy;
+         mnlDebugData.position.verticalAccuracyMeters       = location.v_accuracy;
+         mnlDebugData.position.speedAccuracyMetersPerSecond = location.s_accuracy;
+         mnlDebugData.position.bearingAccuracyDegrees       = location.b_accuracy;
+    } else {
+        // Do not report this location to GLP to avoid strange TTFF time issue
+        LOGW("we have a location when gps_state_intent: %s (%d)",
+                gpshal_state_to_string(state), state);
+    }
+}
+static void update_gps_status(gps_status status) {
+    GpsStatus s;
+    LOGD("  status=%d", status);
+    s.size   = sizeof(s);
+    s.status = status;
+    g_gpshal_ctx.gps_cbs->status_cb(&s);
+}
+
+static void update_gps_sv(gnss_sv_info sv) {
+
+   // GPSHAL_DEBUG_FUNC_SCOPE;
+    int i;
+    GnssSvStatus_ext gss;
+    //dump_gnss_sv_info(sv);
+    gss.size = sizeof(gss);
+    gss.num_svs = sv.num_svs;
+    if (gss.num_svs > GNSS_MAX_SVS) {
+        gss.num_svs = GNSS_MAX_SVS;
+    }
+    for (i = 0; i < gss.num_svs; i++) {
+        GnssSvInfo* dst = &gss.gnss_sv_list[i].legacySvInfo;
+        gnss_sv*    src = &sv.sv_list[i];
+        dst->size = sizeof(*dst);
+        fieldp_copy(dst, src, svid);
+        fieldp_copy(dst, src, constellation);
+        fieldp_copy(dst, src, c_n0_dbhz);
+        fieldp_copy(dst, src, elevation);
+        fieldp_copy(dst, src, azimuth);
+        fieldp_copy(dst, src, flags);
+        fieldp_copy(&gss.gnss_sv_list[i], src, carrier_frequency);
+        mnlDebugData.satelliteDataArray[i].svid = gss.gnss_sv_list[i].legacySvInfo.svid;
+        mnlDebugData.satelliteDataArray[i].constellation = gss.gnss_sv_list[i].legacySvInfo.constellation;
+    }
+    g_gpshal_ctx.gps_cbs->gnss_sv_status_cb(&gss);
+}
+
+static void update_nmea(int64_t timestamp, const char* nmea, int length) {
+    /*LOGD("  timestamp=%lld nmea=[%s] length=%d",
+        timestamp, nmea, length);*/
+    g_gpshal_ctx.gps_cbs->nmea_cb(timestamp, nmea, length);
+}
+static void update_gps_capabilities(gps_capabilites capabilities) {
+    LOGD("  capabilities=0x%x", capabilities);
+    g_gpshal_ctx.gps_cbs->set_capabilities_cb(capabilities);
+}
+
+static void update_gps_measurements(gps_data data) {
+   // GPSHAL_DEBUG_FUNC_SCOPE;
+    size_t i;
+    GpsData gd;
+    //dump_gps_data(data);
+    gd.size = sizeof(gd);
+    field_copy(gd, data, measurement_count);
+    for (i = 0; i < GPS_MAX_MEASUREMENT; i++) {
+        GpsMeasurement*  dst = &gd.measurements[i];
+        gps_measurement* src = &data.measurements[i];
+        dst->size  = sizeof(*dst);
+        fieldp_copy(dst, src, flags);
+        fieldp_copy(dst, src, prn);
+        fieldp_copy(dst, src, time_offset_ns);
+        fieldp_copy(dst, src, state);
+        fieldp_copy(dst, src, received_gps_tow_ns);
+        fieldp_copy(dst, src, received_gps_tow_uncertainty_ns);
+        fieldp_copy(dst, src, c_n0_dbhz);
+        fieldp_copy(dst, src, pseudorange_rate_mps);
+        fieldp_copy(dst, src, pseudorange_rate_uncertainty_mps);
+        fieldp_copy(dst, src, accumulated_delta_range_state);
+        fieldp_copy(dst, src, accumulated_delta_range_m);
+        fieldp_copy(dst, src, accumulated_delta_range_uncertainty_m);
+        fieldp_copy(dst, src, pseudorange_m);
+        fieldp_copy(dst, src, pseudorange_uncertainty_m);
+        fieldp_copy(dst, src, code_phase_chips);
+        fieldp_copy(dst, src, code_phase_uncertainty_chips);
+        fieldp_copy(dst, src, carrier_frequency_hz);
+        fieldp_copy(dst, src, carrier_cycles);
+        fieldp_copy(dst, src, carrier_phase);
+        fieldp_copy(dst, src, carrier_phase_uncertainty);
+        fieldp_copy(dst, src, loss_of_lock);
+        fieldp_copy(dst, src, bit_number);
+        fieldp_copy(dst, src, time_from_last_bit_ms);
+        fieldp_copy(dst, src, doppler_shift_hz);
+        fieldp_copy(dst, src, doppler_shift_uncertainty_hz);
+        fieldp_copy(dst, src, multipath_indicator);
+        fieldp_copy(dst, src, snr_db);
+        fieldp_copy(dst, src, elevation_deg);
+        fieldp_copy(dst, src, elevation_uncertainty_deg);
+        fieldp_copy(dst, src, azimuth_deg);
+        fieldp_copy(dst, src, azimuth_uncertainty_deg);
+        fieldp_copy(dst, src, used_in_fix);
+    }
+
+    // To do things like field_copy(gd, data, clock)
+    {
+        GpsClock*  dst = &gd.clock;
+        gps_clock* src = &data.clock;
+        dst->size = sizeof(*dst);
+        fieldp_copy(dst, src, flags);
+        fieldp_copy(dst, src, leap_second);
+        fieldp_copy(dst, src, type);
+        fieldp_copy(dst, src, time_ns);
+        fieldp_copy(dst, src, time_uncertainty_ns);
+        fieldp_copy(dst, src, full_bias_ns);
+        fieldp_copy(dst, src, bias_ns);
+        fieldp_copy(dst, src, bias_uncertainty_ns);
+        fieldp_copy(dst, src, drift_nsps);
+        fieldp_copy(dst, src, drift_uncertainty_nsps);
+    }
+    g_gpshal_ctx.meas_cbs->measurement_callback(&gd);
+}
+
+static void update_gnss_measurements(gnss_data data) {
+    size_t i;
+    GnssData_ext gd;
+    //dump_gnss_data(data);
+    gd.size = sizeof(gd);
+    field_copy(gd, data, measurement_count);
+    for (i = 0; i < MTK_HAL_GNSS_MAX_MEASUREMENT; i++) {
+        GnssMeasurement*  dst = &gd.measurements[i].legacyMeasurement;
+        gnss_measurement*  src = &data.measurements[i];
+        dst->size  = sizeof(*dst);
+        fieldp_copy(dst, src, flags);
+        fieldp_copy(dst, src, svid);
+        fieldp_copy(dst, src, constellation);
+        fieldp_copy(dst, src, time_offset_ns);
+        fieldp_copy(dst, src, state);
+        fieldp_copy(dst, src, received_sv_time_in_ns);
+        fieldp_copy(dst, src, received_sv_time_uncertainty_in_ns);
+        fieldp_copy(dst, src, c_n0_dbhz);
+        fieldp_copy(dst, src, pseudorange_rate_mps);
+        fieldp_copy(dst, src, pseudorange_rate_uncertainty_mps);
+        fieldp_copy(dst, src, accumulated_delta_range_state);
+        fieldp_copy(dst, src, accumulated_delta_range_m);
+        fieldp_copy(dst, src, accumulated_delta_range_uncertainty_m);
+        fieldp_copy(dst, src, carrier_frequency_hz);
+        fieldp_copy(dst, src, carrier_cycles);
+        fieldp_copy(dst, src, carrier_phase);
+        fieldp_copy(dst, src, carrier_phase_uncertainty);
+        fieldp_copy(dst, src, multipath_indicator);
+        fieldp_copy(dst, src, snr_db);
+        fieldp_copy(&gd.measurements[i], src, agc_level_db);
+    }
+    // To do things like field_copy(gd, data, clock)
+    {
+        GnssClock*  dst = &gd.clock;
+        gnss_clock* src = &data.clock;
+        dst->size = sizeof(*dst);
+        fieldp_copy(dst, src, flags);
+        fieldp_copy(dst, src, leap_second);
+        fieldp_copy(dst, src, time_ns);
+        fieldp_copy(dst, src, time_uncertainty_ns);
+        fieldp_copy(dst, src, full_bias_ns);
+        fieldp_copy(dst, src, bias_ns);
+        fieldp_copy(dst, src, bias_uncertainty_ns);
+        fieldp_copy(dst, src, drift_nsps);
+        fieldp_copy(dst, src, drift_uncertainty_nsps);
+        fieldp_copy(dst, src, hw_clock_discontinuity_count);
+    }
+
+    g_gpshal_ctx.meas_cbs->gnss_measurement_callback(&gd);
+}
+static void update_gps_navigation(gps_nav_msg msg) {
+  //  GPSHAL_DEBUG_FUNC_SCOPE;
+    GpsNavigationMessage gnm;
+    //dump_gps_nav_msg(msg);
+    gnm.size = sizeof(gnm);
+    field_copy(gnm, msg, prn);
+    field_copy(gnm, msg, type);
+    field_copy(gnm, msg, status);
+    field_copy(gnm, msg, message_id);
+    field_copy(gnm, msg, submessage_id);
+    field_copy(gnm, msg, data_length);
+    gnm.data = (uint8_t*) msg.data;
+    g_gpshal_ctx.navimsg_cbs->navigation_message_callback(&gnm);
+}
+
+static void update_gnss_navigation(gnss_nav_msg msg) {
+    GnssNavigationMessage gnm;
+    //dump_gnss_nav_msg(msg);
+    gnm.size = sizeof(gnm);
+    field_copy(gnm, msg, svid);
+    field_copy(gnm, msg, type);
+    field_copy(gnm, msg, status);
+    field_copy(gnm, msg, message_id);
+    field_copy(gnm, msg, submessage_id);
+    field_copy(gnm, msg, data_length);
+    gnm.data = (uint8_t*) msg.data;
+    g_gpshal_ctx.navimsg_cbs->gnss_navigation_message_callback(&gnm);
+}
+
+static void request_wakelock() {
+   // GPSHAL_DEBUG_FUNC_SCOPE;
+    g_gpshal_ctx.gps_cbs->acquire_wakelock_cb();
+}
+static void release_wakelock() {
+   // GPSHAL_DEBUG_FUNC_SCOPE;
+    g_gpshal_ctx.gps_cbs->release_wakelock_cb();
+}
+static void request_utc_time() {
+   // GPSHAL_DEBUG_FUNC_SCOPE;
+    g_gpshal_ctx.gps_cbs->request_utc_time_cb();
+}
+static void request_data_conn(struct sockaddr_storage* addr) {
+  //  GPSHAL_DEBUG_FUNC_SCOPE;
+    UNUSED(addr);
+    AGpsStatus as;
+    as.size   = sizeof(AGpsStatus);  // our imp supports v3
+    as.type   = AGPS_TYPE_SUPL;
+    as.status = GPS_REQUEST_AGPS_DATA_CONN;
+    // as.ipaddr = INADDR_NONE; // not used in v3
+    as.addr   = *addr;
+    g_gpshal_ctx.agps_cbs->status_cb(&as);
+}
+static void release_data_conn() {
+    // GPSHAL_DEBUG_FUNC_SCOPE;
+    AGpsStatus as;
+    as.size   = sizeof(AGpsStatus_v1);  // use v1 size to omit optional fields
+    as.type   = AGPS_TYPE_SUPL;
+    as.status = GPS_RELEASE_AGPS_DATA_CONN;
+    g_gpshal_ctx.agps_cbs->status_cb(&as);
+}
+static void request_ni_notify(int session_id, agps_notify_type type, const char* requestor_id,
+        const char* client_name, ni_encoding_type requestor_id_encoding,
+        ni_encoding_type client_name_encoding) {
+    /*LOGD("  session_id=%d type=%d requestor_id=[%s] client_name=[%s] requestor_id_encoding=%d client_name_encoding=%d",
+        session_id, type, requestor_id, client_name, requestor_id_encoding, client_name_encoding);*/
+    GpsNiNotification gnn;
+    gnn.size = sizeof(gnn);
+    gnn.notification_id = session_id;
+    gnn.ni_type = GPS_NI_TYPE_UMTS_SUPL;
+    switch (type) {
+        case AGPS_NOTIFY_TYPE_NOTIFY_ONLY:
+            gnn.notify_flags = GPS_NI_NEED_NOTIFY;
+            break;
+        case AGPS_NOTIFY_TYPE_NOTIFY_ALLOW_NO_ANSWER:
+            gnn.notify_flags = GPS_NI_NEED_NOTIFY|GPS_NI_NEED_VERIFY;
+            break;
+        case AGPS_NOTIFY_TYPE_NOTIFY_DENY_NO_ANSWER:
+            gnn.notify_flags = GPS_NI_NEED_NOTIFY|GPS_NI_NEED_VERIFY;
+            break;
+        case AGPS_NOTIFY_TYPE_PRIVACY:
+            gnn.notify_flags = GPS_NI_PRIVACY_OVERRIDE;
+            break;
+        default:
+            gnn.notify_flags = 0;
+    }
+    gnn.timeout          = 8;
+    gnn.default_response = GPS_NI_RESPONSE_NORESP;
+    MNLD_STRNCPY(gnn.requestor_id, requestor_id,sizeof(gnn.requestor_id));
+    MNLD_STRNCPY(gnn.text,client_name,sizeof(gnn.text));
+    gnn.requestor_id_encoding = requestor_id_encoding;
+    gnn.text_encoding         = client_name_encoding;
+    gnn.extras[0] = 0;  // be an empty string ""
+    g_gpshal_ctx.gpsni_cbs->notify_cb(&gnn);
+}
+static void request_set_id(request_setid flags) {
+    //LOGD("  flags=0x%x", flags);
+    if (g_gpshal_ctx.agpsril_cbs) {
+        g_gpshal_ctx.agpsril_cbs->request_setid(flags);
+    }
+}
+static void request_ref_loc(request_refloc flags) {
+    //LOGD("  flags=0x%x", flags);
+    if (g_gpshal_ctx.agpsril_cbs) {
+        g_gpshal_ctx.agpsril_cbs->request_refloc(flags);
+    }
+}
+static void output_vzw_debug(const char* str) {
+    int len;
+    len = strlen(str)+1;
+    if (len > VZW_DEBUG_STRING_MAXLEN) {
+        len = VZW_DEBUG_STRING_MAXLEN;
+    }
+    LOGD("len=%d str=%s", len, str);
+    VzwDebugData vzwdebugdata;
+    vzwdebugdata.size = sizeof(VzwDebugData);
+    memcpy(vzwdebugdata.vzw_msg_data, str, len);
+    vzwdebugdata.vzw_msg_data[VZW_DEBUG_STRING_MAXLEN - 1] = 0;
+
+    if (g_gpshal_ctx.vzw_debug_cbs) {
+        g_gpshal_ctx.vzw_debug_cbs->vzw_debug_cb(&vzwdebugdata);
+    }
+}
+
+static void update_gnss_name(const char* name, int length) {
+    LOGD("length=%d, name=%s", length, name);
+    if (g_gpshal_ctx.gps_cbs) {
+        g_gpshal_ctx.gps_cbs->set_name_cb(name, length);
+    }
+}
+
+static void request_nlp(bool independentFromGnss) {
+    LOGD("request nlp[%d]", independentFromGnss);
+    if (g_gpshal_ctx.gps_cbs) {
+        g_gpshal_ctx.gps_cbs->request_location_cb(independentFromGnss);
+    }
+}
+
+static mnl2hal_interface gpshal_mnl2hal_interface = {
+    update_mnld_reboot,
+    update_location,
+    update_gps_status,
+    update_gps_sv,
+    update_nmea,
+    update_gps_capabilities,
+    update_gps_measurements,
+    update_gps_navigation,
+    update_gnss_measurements,
+    update_gnss_navigation,
+    request_wakelock,
+    release_wakelock,
+    request_utc_time,
+    request_data_conn,
+    release_data_conn,
+    request_ni_notify,
+    request_set_id,
+    request_ref_loc,
+    output_vzw_debug,
+    update_gnss_name,
+    request_nlp,
+};
+
+//=========================================================
+
+void gpshal_worker_thread(void *arg) {
+   // GPSHAL_DEBUG_FUNC_SCOPE;
+    struct epoll_event events[MAX_EPOLL_EVENT];
+    UNUSED(arg);
+
+    while (true) {
+        int i;
+        int n;
+
+        n = epoll_wait(g_gpshal_ctx.fd_worker_epoll, events, MAX_EPOLL_EVENT, -1);
+
+        if (n == -1) {
+            if (errno == EINTR) {
+                continue;
+            } else {
+                LOGE("epoll_wait failure reason=[%s]%d", strerror(errno), errno);
+                return;
+            }
+        }
+
+        for (i = 0; i < n; i++) {
+            if (events[i].data.fd == g_gpshal_ctx.fd_mnl2hal) {
+                if (events[i].events & EPOLLIN) {
+                    mnl2hal_hdlr(g_gpshal_ctx.fd_mnl2hal,
+                            &gpshal_mnl2hal_interface);
+                }
+            } else {
+                LOGE("%s() unknown fd=%d",
+                        __func__, events[i].data.fd);
+            }
+        }
+    }  // of while (true)
+}
diff --git a/src/connectivity/gps/gps_hal/src/gpsinf.c b/src/connectivity/gps/gps_hal/src/gpsinf.c
new file mode 100644
index 0000000..b8cb228
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/src/gpsinf.c
@@ -0,0 +1,395 @@
+/* Copyright Statement:
+ *
+ * This software/firmware and related documentation ("MediaTek Software") are
+ * protected under relevant copyright laws. The information contained herein
+ * is confidential and proprietary to MediaTek Inc. and/or its licensors.
+ * Without the prior written permission of MediaTek inc. and/or its licensors,
+ * any reproduction, modification, use or disclosure of MediaTek Software,
+ * and information contained herein, in whole or in part, shall be strictly prohibited.
+ *
+ * MediaTek Inc. (C) 2016. All rights reserved.
+ *
+ * BY OPENING THIS FILE, RECEIVER HEREBY UNEQUIVOCALLY ACKNOWLEDGES AND AGREES
+ * THAT THE SOFTWARE/FIRMWARE AND ITS DOCUMENTATIONS ("MEDIATEK SOFTWARE")
+ * RECEIVED FROM MEDIATEK AND/OR ITS REPRESENTATIVES ARE PROVIDED TO RECEIVER ON
+ * AN "AS-IS" BASIS ONLY. MEDIATEK EXPRESSLY DISCLAIMS ANY AND ALL WARRANTIES,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NONINFRINGEMENT.
+ * NEITHER DOES MEDIATEK PROVIDE ANY WARRANTY WHATSOEVER WITH RESPECT TO THE
+ * SOFTWARE OF ANY THIRD PARTY WHICH MAY BE USED BY, INCORPORATED IN, OR
+ * SUPPLIED WITH THE MEDIATEK SOFTWARE, AND RECEIVER AGREES TO LOOK ONLY TO SUCH
+ * THIRD PARTY FOR ANY WARRANTY CLAIM RELATING THERETO. RECEIVER EXPRESSLY ACKNOWLEDGES
+ * THAT IT IS RECEIVER'S SOLE RESPONSIBILITY TO OBTAIN FROM ANY THIRD PARTY ALL PROPER LICENSES
+ * CONTAINED IN MEDIATEK SOFTWARE. MEDIATEK SHALL ALSO NOT BE RESPONSIBLE FOR ANY MEDIATEK
+ * SOFTWARE RELEASES MADE TO RECEIVER'S SPECIFICATION OR TO CONFORM TO A PARTICULAR
+ * STANDARD OR OPEN FORUM. RECEIVER'S SOLE AND EXCLUSIVE REMEDY AND MEDIATEK'S ENTIRE AND
+ * CUMULATIVE LIABILITY WITH RESPECT TO THE MEDIATEK SOFTWARE RELEASED HEREUNDER WILL BE,
+ * AT MEDIATEK'S OPTION, TO REVISE OR REPLACE THE MEDIATEK SOFTWARE AT ISSUE,
+ * OR REFUND ANY SOFTWARE LICENSE FEES OR SERVICE CHARGE PAID BY RECEIVER TO
+ * MEDIATEK FOR SUCH MEDIATEK SOFTWARE AT ISSUE.
+ *
+ * The following software/firmware and/or related documentation ("MediaTek Software")
+ * have been modified by MediaTek Inc. All revisions are subject to any receiver's
+ * applicable license agreements with MediaTek Inc.
+ */
+#include "gpshal.h"
+#include "hal2mnl_interface.h"
+#include "mtk_lbs_utility.h"
+#include "gpshal_param_check.h"
+#include "mtk_auto_log.h"
+
+#ifdef LOG_TAG
+#undef LOG_TAG
+#define LOG_TAG "gpsinf"
+#endif
+
+extern DebugData mnlDebugData; //for GNSS HIDL v1.1 GPS debug interface
+
+//=========================================================
+
+extern struct hw_module_t HAL_MODULE_INFO_SYM;
+
+//=========================================================
+// Gps Measurement Interface
+
+// Thread: BackgroundThread
+//      GpsMeasurementsProvider uses GpsLocationProvider's handler
+static int measinf_init(GpsMeasurementCallbacks_ext* callbacks, bool enableFullTracking) {
+    g_gpshal_ctx.meas_cbs = callbacks;
+    int ret = hal2mnl_set_gps_measurement(true, enableFullTracking);
+    return (ret > 0)?
+            GPS_GEOFENCE_OPERATION_SUCCESS :
+            GPS_GEOFENCE_ERROR_GENERIC;
+}
+
+// Thread: BackgroundThread
+//      GpsMeasurementsProvider uses GpsLocationProvider's handler
+static void measinf_close(void) {
+    hal2mnl_set_gps_measurement(false, false);
+}
+
+const GpsMeasurementInterface_ext mtk_gps_meas_inf = {
+    sizeof(GpsMeasurementInterface_ext),
+    measinf_init,
+    measinf_close
+};
+
+//=========================================================
+// Gps Navigation Message Interface
+
+// Thread: BackgroundThread
+// GpsNavigationMessageProvider uses GpsLocationProvider's handler
+static int navimsginf_init(GpsNavigationMessageCallbacks* callbacks) {
+    g_gpshal_ctx.navimsg_cbs = callbacks;
+    int ret = hal2mnl_set_gps_navigation(true);
+    return (ret > 0)?
+            GPS_NAVIGATION_MESSAGE_OPERATION_SUCCESS :
+            GPS_NAVIGATION_MESSAGE_ERROR_GENERIC;
+}
+
+// Thread: BackgroundThread
+//      GpsNavigationMessageProvider uses GpsLocationProvider's handler
+static void navimsginf_close(void) {
+    hal2mnl_set_gps_navigation(false);
+}
+
+const GpsNavigationMessageInterface mtk_navi_msg_inf = {
+    sizeof(GpsNavigationMessageInterface),
+    navimsginf_init,
+    navimsginf_close
+};
+
+static int vzwdebuginf_init(VzwDebugCallbacks* callbacks) {
+    g_gpshal_ctx.vzw_debug_cbs = callbacks;
+    return 0;
+}
+
+static void vzwdebuginf_set(bool enabled) {
+    hal2mnl_set_vzw_debug(enabled);
+}
+
+const VzwDebugInterface mtk_vzw_debug_inf = {
+    sizeof(VzwDebugInterface),
+    vzwdebuginf_init,
+    vzwdebuginf_set
+};
+
+static void gnss_configuration_update(const char* config_data, int32_t length) {
+    hal2mnl_update_gnss_config(config_data, length);
+}
+
+static void gnss_setBlacklist(long long* blacklist, int32_t size) {
+    //hal2mnl_setBlacklist(blacklist, size);
+    UNUSED(blacklist);
+    UNUSED(size);
+}
+
+const GnssConfigurationInterface_ext mtk_gnss_config_inf = {
+    sizeof(GnssConfigurationInterface_ext),
+    gnss_configuration_update,
+    gnss_setBlacklist
+};
+
+static bool get_internal_state(DebugData* debugData) {
+    memcpy(debugData, &mnlDebugData, sizeof(DebugData));
+    return true;
+}
+
+const GpsDebugInterface_ext mtk_gps_debug_inf = {
+    sizeof(GpsDebugInterface_ext),
+    get_internal_state
+};
+
+//=========================================================
+// Implementation of
+//     Gps Iterface
+
+// Thread: Main thread of system server
+// Call seq:
+//     LocationManagerService.systemRunning
+//     LocationManagerService.loadProvidersLocked
+//     GpsLocationProvider.static
+//     android_location_GpsLocationProvider_class_init_native
+//     sGpsInterface->get_extension
+static const void* gpsinf_get_extension(const char* name) {
+#ifndef CONFIG_GPS_MT3303
+    if (strcmp(name, AGPS_INTERFACE) == 0) {
+        return &mtk_agps_inf;
+    }
+    if (strcmp(name, GPS_NI_INTERFACE) == 0) {
+        return &mtk_gps_ni_inf;
+    }
+    if (strcmp(name, AGPS_RIL_INTERFACE) == 0) {
+        return &mtk_agps_ril_inf;
+    }
+#endif
+    if (strcmp(name, GPS_MEASUREMENT_INTERFACE) == 0) {
+       return &mtk_gps_meas_inf;
+    }
+    if (strcmp(name, GPS_NAVIGATION_MESSAGE_INTERFACE) == 0) {
+       return &mtk_navi_msg_inf;
+    }
+
+    if (strcmp(name, VZW_DEBUG_INTERFACE) == 0) {
+       return &mtk_vzw_debug_inf;
+    }
+
+#if 0
+    if (strcmp(name, GPS_GEOFENCING_INTERFACE) == 0) {
+       return &mtkGeofence_inf;
+    }
+#endif
+
+#if 0  // not supported, even in our MP branches
+    if (!strcmp(name, GPS_GEOFENCING_INTERFACE))
+        return &mtk_gps_geofencing_inf;
+#endif
+
+    if (!strcmp(name, GNSS_CONFIGURATION_INTERFACE))
+        return &mtk_gnss_config_inf;
+
+#if 0  // not ready, even in Google's GPS JNI
+    if (strcmp(name, SUPL_CERTIFICATE_INTERFACE) == 0) {
+       return &mtk_supl_cert_inf;
+    }
+#endif
+#if 0  // Similar to our EPO but we will do it in mnld.
+    if (!strcmp(name, GPS_XTRA_INTERFACE))
+        return &mtk_gps_xtra_inf;
+#endif
+    if (!strcmp(name, GPS_DEBUG_INTERFACE)) {
+        return &mtk_gps_debug_inf;
+    }
+    return NULL;  // unsupported extension
+}
+
+// Thread: BackgroundThread
+//     Its looper is shared by a lot of services including
+//         LocationManagerService's handler
+//         GpsLocationProvider's handler
+//         GpsLocationProvider's broadcast receiver
+// Call seq:
+//     GpsLocationProvider.ProviderHandler.handleMessage
+//     GpsLocationProvider.handleEnable
+//     GpsLocationProvider.native_init
+//     android_location_GpsLocationProvider_init
+//     sGpsInterface->init
+static int gpsinf_init(GpsCallbacks_ext* callbacks) {
+    // GPSHAL_DEBUG_FUNC_SCOPE2(g_gpshal_ctx.mutex_gps_state_intent);
+    if (gpshal_gpscbs_save(callbacks) != 0) {
+        return -1;    //  error
+    }
+
+    gpshal_set_gps_state_intent(GPSHAL_STATE_INIT);
+    gpshal2mnl_gps_init();
+    return 0;  // OK to init
+}
+
+// Thread: BackgroundThread
+static int gpsinf_start(void) {
+    // GPSHAL_DEBUG_FUNC_SCOPE2(g_gpshal_ctx.mutex_gps_state_intent);
+    gpshal_set_gps_state_intent(GPSHAL_STATE_START);
+    gpshal2mnl_gps_start();
+    return 0;  // OK to start
+}
+
+// Thread: BackgroundThread
+static int gpsinf_stop(void) {
+    // GPSHAL_DEBUG_FUNC_SCOPE2(g_gpshal_ctx.mutex_gps_state_intent);
+    gpshal_set_gps_state_intent(GPSHAL_STATE_STOP);
+    gpshal2mnl_gps_stop();
+    return 0;  // OK to stop
+}
+
+// Thread: BackgroundThread
+static void gpsinf_cleanup(void) {
+    // GPSHAL_DEBUG_FUNC_SCOPE2(g_gpshal_ctx.mutex_gps_state_intent);
+    gpshal_set_gps_state_intent(GPSHAL_STATE_CLEANUP);
+    gpshal2mnl_gps_cleanup();
+}
+
+// Thread: BackgroundThread
+static int gpsinf_inject_time(GpsUtcTime time, int64_t timeReference, int uncertainty) {
+    hal2mnl_gps_inject_time(time, timeReference, uncertainty);
+    return 0;  // 0:ok,   non-zero: error; but GPS JNI will ignore it
+}
+
+// Thread: BackgroundThread
+//     NetworkLocationListener uses the looper of GpsLocationProvider's handler
+static int gpsinf_inject_location(
+        double latitude,
+        double longitude,
+        float  accuracy) {
+    hal2mnl_gps_inject_location(latitude, longitude, accuracy);
+    return 0;  // 0:ok,   non-zero: error; but GPS JNI will ignore it
+}
+
+// Thread: Binder Thread of LocationManagerService
+//
+// Call seq:
+//     LocationManagerService.sendExtraCommand
+//     GpsLocationProvider.sendExtraCommand
+//     GpsLocationProvider.deleteAidingData
+//     GpsLocationProvider.native_delete_aiding_data
+//     android_location_GpsLocationProvider_delete_aiding_data
+//     sGpsInterface->delete_aiding_data
+static void gpsinf_delete_aiding_data(GpsAidingData flags) {
+    hal2mnl_gps_delete_aiding_data(flags);
+}
+
+// Thread: BackgroundThread or ???
+//     GpsLocationProvider's handler may call it
+//     GpsLocationProvider's mBroadcastReceiver may call it (PowerManager's intent)
+static int gpsinf_set_position_mode(
+        GpsPositionMode mode,
+        GpsPositionRecurrence recurrence,
+        uint32_t min_interval,
+        uint32_t preferred_accuracy,
+        uint32_t preferred_time,
+        bool lowPowerMode) {
+    hal2mnl_gps_set_position_mode(
+            mode,
+            recurrence,
+            min_interval,
+            preferred_accuracy,
+            preferred_time,
+            lowPowerMode);
+    return 0;  // 0:ok,   non-zero: error; GLP will show log if error
+}
+
+static int gpsinf_inject_fused_location(
+        double latitude,
+        double longitude,
+        float  accuracy) {
+    // TODO:  hal2mnl_gps_inject_fused_location(latitude, longitude, accuracy);
+    UNUSED(latitude);
+    UNUSED(longitude);
+    UNUSED(accuracy);
+    return 0;  // 0:ok,   non-zero: error; but GPS JNI will ignore it
+}
+
+static const GpsInterface_ext  mtk_gps_inf = {
+    sizeof(GpsInterface_ext),
+    gpsinf_init,
+    gpsinf_start,
+    gpsinf_stop,
+    gpsinf_cleanup,
+    gpsinf_inject_time,
+    gpsinf_inject_location,
+    gpsinf_delete_aiding_data,
+    gpsinf_set_position_mode,
+    gpsinf_get_extension,
+    gpsinf_inject_fused_location,
+};
+
+#ifdef __ANDROID_OS__
+//=========================================================
+// Between
+//     Gps Interface
+//     Hardware Module Interface
+
+static const GpsInterface_ext* gps_device__get_gps_interface(
+        __unused struct gps_device_t_ext* device) {
+    GPS_DEVICE__GET_GPS_INTERFACE__CHECK_PARAM;
+    hal2mnl_hal_reboot();
+    return &mtk_gps_inf;
+}
+
+static const struct gps_device_t_ext gps_device = {
+    .common = {                           // hw_device_t
+        .tag     = HARDWARE_DEVICE_TAG,
+        .version = 0,                     // GPS JNI will not use it
+        .module  = &HAL_MODULE_INFO_SYM,
+        .reserved = {0},
+        .close   = NULL                   // GPS JNI will not call it
+        },
+    .get_gps_interface = gps_device__get_gps_interface
+};
+
+//=========================================================
+// Implementation of
+//     Hardware Module Interface
+
+static int gps_hw_module_open(
+        __unused const struct hw_module_t* module,
+        __unused char const* id,
+        struct hw_device_t** device) {
+    GPS_HW_MODULE_OPEN__CHECK_PARAM;
+    *device = (struct hw_device_t*)&gps_device;
+    return 0;  // OK: refer to the cpp of GPS JNI
+}
+
+static struct hw_module_methods_t gps_hw_module_methods = {
+    .open = gps_hw_module_open
+};
+
+struct hw_module_t HAL_MODULE_INFO_SYM = {
+    .tag = HARDWARE_MODULE_TAG,
+    .version_major = 1,
+    .version_minor = 0,
+    .id  = GPS_HARDWARE_MODULE_ID,
+    .name   = "MediaTek GPS Hardware Module",
+    .author = "MediaTek, Inc.",
+    .methods = &gps_hw_module_methods,
+    .dso     = NULL,
+    .reserved = {0}
+};
+#else
+//=========================================================
+// Between
+//     Gps Interface
+//     Hardware Module Interface
+
+const GpsInterface_ext* gps_device__get_gps_interface(struct gps_device_t_ext* device) 
+{
+    LOGD("welcome enter libgpshal world\n");
+    hal2mnl_hal_reboot();
+
+    return &mtk_gps_inf;
+}
+
+const struct gps_device_t_ext linux_gps_device = {
+    .get_gps_interface = gps_device__get_gps_interface
+};
+
+#endif //__ANDROID_OS__
diff --git a/src/connectivity/gps/gps_hal/src/gpsinf3337.c b/src/connectivity/gps/gps_hal/src/gpsinf3337.c
new file mode 100644
index 0000000..d59291c
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/src/gpsinf3337.c
@@ -0,0 +1,2290 @@
+/* Copyright Statement:
+ *
+ * This software/firmware and related documentation ("MediaTek Software") are
+ * protected under relevant copyright laws. The information contained herein
+ * is confidential and proprietary to MediaTek Inc. and/or its licensors.
+ * Without the prior written permission of MediaTek inc. and/or its licensors,
+ * any reproduction, modification, use or disclosure of MediaTek Software,
+ * and information contained herein, in whole or in part, shall be strictly prohibited.
+ *
+ * MediaTek Inc. (C) 2010. All rights reserved.
+ *
+ * BY OPENING THIS FILE, RECEIVER HEREBY UNEQUIVOCALLY ACKNOWLEDGES AND AGREES
+ * THAT THE SOFTWARE/FIRMWARE AND ITS DOCUMENTATIONS ("MEDIATEK SOFTWARE")
+ * RECEIVED FROM MEDIATEK AND/OR ITS REPRESENTATIVES ARE PROVIDED TO RECEIVER ON
+ * AN "AS-IS" BASIS ONLY. MEDIATEK EXPRESSLY DISCLAIMS ANY AND ALL WARRANTIES,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NONINFRINGEMENT.
+ * NEITHER DOES MEDIATEK PROVIDE ANY WARRANTY WHATSOEVER WITH RESPECT TO THE
+ * SOFTWARE OF ANY THIRD PARTY WHICH MAY BE USED BY, INCORPORATED IN, OR
+ * SUPPLIED WITH THE MEDIATEK SOFTWARE, AND RECEIVER AGREES TO LOOK ONLY TO SUCH
+ * THIRD PARTY FOR ANY WARRANTY CLAIM RELATING THERETO. RECEIVER EXPRESSLY ACKNOWLEDGES
+ * THAT IT IS RECEIVER'S SOLE RESPONSIBILITY TO OBTAIN FROM ANY THIRD PARTY ALL PROPER LICENSES
+ * CONTAINED IN MEDIATEK SOFTWARE. MEDIATEK SHALL ALSO NOT BE RESPONSIBLE FOR ANY MEDIATEK
+ * SOFTWARE RELEASES MADE TO RECEIVER'S SPECIFICATION OR TO CONFORM TO A PARTICULAR
+ * STANDARD OR OPEN FORUM. RECEIVER'S SOLE AND EXCLUSIVE REMEDY AND MEDIATEK'S ENTIRE AND
+ * CUMULATIVE LIABILITY WITH RESPECT TO THE MEDIATEK SOFTWARE RELEASED HEREUNDER WILL BE,
+ * AT MEDIATEK'S OPTION, TO REVISE OR REPLACE THE MEDIATEK SOFTWARE AT ISSUE,
+ * OR REFUND ANY SOFTWARE LICENSE FEES OR SERVICE CHARGE PAID BY RECEIVER TO
+ * MEDIATEK FOR SUCH MEDIATEK SOFTWARE AT ISSUE.
+ *
+ * The following software/firmware and/or related documentation ("MediaTek Software")
+ * have been modified by MediaTek Inc. All revisions are subject to any receiver's
+ * applicable license agreements with MediaTek Inc.
+ */
+#include <errno.h>
+#include <pthread.h>
+#include <fcntl.h>
+#include <sys/epoll.h>
+#include <math.h>
+#include <time.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <semaphore.h>
+#include <sys/ioctl.h>
+#include <sys/time.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <signal.h>
+#include <linux/mtk_agps_common.h>
+#include <cutils/android_filesystem_config.h>
+
+#include "hardware/gps_mtk.h"
+#include "gpshal.h"
+#include "mtk_lbs_utility.h"
+#include "data_coder.h"
+#include <termios.h>
+#include "mtk_auto_log.h"
+
+#define LOCATION_NLP_FIX MTK_GPS_DATA_PATH"LOCATION.DAT"
+#define  LOG_TAG  "gps_mtk_3337"
+
+#if ANDROID_MNLD_PROP_SUPPORT
+#include <cutils/properties.h>
+#endif
+
+#ifdef HAVE_LIBC_SYSTEM_PROPERTIES
+#define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
+#include <sys/_system_properties.h>
+#endif
+
+
+
+/* the name of the controlled socket */
+#define  GPS_POWER_NAME       "/dev/gps"
+#define  GPS_TTY_NAME       "/dev/ttyMT1"
+
+#define  MNLD_HAL2GPS       "/dev/mt3337_gpsonly"
+#define MNL_CONFIG_STATUS   "persist.vendor.radio.mnl.prop"
+
+#define PMTK_SOCKET_COM_PORT 49995
+#define PMTK_SERVER_BACKLOG 5
+#define INVALID_SOCKET -1
+#define INVALID_FD -1
+#define  GPS_OP   "AT%GPS"
+#define  GNSS_OP  "AT%GNSS"
+#define  GPS_AT_ACK_SIZE        60
+
+#define MTKEPO_SV_NUMBER 32
+#define MTKEPO_RECORD_SIZE 72
+#define MTKEPO_SEGMENT_NUM (30 * 4)
+
+#define  GPS_DEBUG  1
+#define  NEMA_DEBUG 0   /*the flag works if GPS_DEBUG is defined*/
+#if GPS_DEBUG
+#define  TRC(f)       ALOGD("%s", __func__)
+#define  ERR(f, ...)  ALOGE("%s: line = %d" f, __func__,__LINE__, ##__VA_ARGS__)
+#define  WAN(f, ...)  ALOGW("%s: line = %d" f, __func__, __LINE__,##__VA_ARGS__)
+#define DBG(f, ...) ALOGD("%s: line = %d" f, __func__, __LINE__,##__VA_ARGS__)
+#define VER(f, ...) ((void)0) //((void)0)//
+#else
+#  define DBG(...)    ((void)0)
+#  define VER(...)    ((void)0)
+#endif
+
+#define GPS_POWER_IOCTL _IOW('G', 0, int)
+static int flag_unlock = 0;
+GpsStatus sta;
+
+extern struct hw_module_t HAL_MODULE_INFO_SYM;
+
+typedef  unsigned int             UINT4;
+typedef  signed int               INT4;
+typedef unsigned char           UINT8;
+typedef signed char             INT8;
+typedef unsigned short int      UINT16;
+typedef signed short int        INT16;
+typedef unsigned int            UINT32;
+typedef signed int              INT32;
+typedef signed long long       INT64;
+
+#pragma pack(4) // Align by 4 byte
+typedef struct
+{
+   UINT32 size;
+   UINT16 flag;
+   INT16 leapsecond;
+   UINT8 type;
+   INT64 TimeInNs;
+   double TimeUncertaintyInNs;
+   INT64 FullBiasInNs;
+   double BiasInNs;
+   double BiasUncertaintyInNs;
+   double DriftInNsPerSec;
+   double DriftUncertaintyInNsPerSec;
+}MTK_GPS_CLOCK;
+#pragma pack()
+
+typedef struct{
+    GpsUtcTime time;
+    int64_t timeReference;
+    int uncertainty;
+} ntp_context;
+
+typedef struct{
+    double latitude;
+    double longitude;
+    float accuracy;
+    struct timespec ts;
+    unsigned char  type;
+    unsigned char  started;
+} nlp_context;
+
+/*****************************************************************************/
+/*    MTK device control                                                  */
+/*****************************************************************************/
+enum {
+    MNL_CMD_UNKNOWN = -1,
+    /*command send from GPS HAL*/
+    MNL_CMD_INIT            = 0x00,
+    MNL_CMD_CLEANUP         = 0x01,
+    MNL_CMD_STOP            = 0x02,
+    MNL_CMD_START           = 0x03,
+    MNL_CMD_RESTART         = 0x04,    /*restart MNL process*/
+    MNL_CMD_RESTART_HOT     = 0x05,    /*restart MNL by PMTK command: hot start*/
+    MNL_CMD_RESTART_WARM    = 0x06,    /*restart MNL by PMTK command: warm start*/
+    MNL_CMD_RESTART_COLD    = 0x07,    /*restart MNL by PMTK command: cold start*/
+    MNL_CMD_RESTART_FULL    = 0x08,    /*restart MNL by PMTK command: full start*/
+    MNL_CMD_RESTART_AGPS    = 0x09,    /*restart MNL by PMTK command: AGPS start*/
+    MNL_CMD_GPSMEASUREMENT_INIT = 0x15,
+    MNL_CMD_GPSMEASUREMENT_CLOSE = 0x16,
+
+
+    MNL_CMD_GPSNAVIGATION_INIT = 0x17,
+    MNL_CMD_GPSNAVIGATION_CLOSE = 0x18,
+    MNL_CMD_GPS_LOG_WRITE = 0x40,
+
+    MNL_CMD_ENABLE_AGPS_DEBUG = 0x42,
+    MNL_CMD_DISABLE_AGPS_DEBUG = 0x43,
+};
+
+enum {
+    HAL_CMD_STOP_UNKNOWN = -1,
+    HAL_CMD_MNL_DIE = 0x41,
+    HAL_CMD_GPS_ICON = 0x42,
+
+    MNL_CMD_GPS_INJECT_TIME = 0x46,
+    MNL_CMD_GPS_INJECT_LOCATION = 0x47,
+    MNL_CMD_GPS_INJECT_TIME_REQ = 0x48,
+    MNL_CMD_GPS_INJECT_LOCATION_REQ = 0x49,
+
+    MNL_CMD_GPS_NLP_LOCATION_REQ = 0x4a,
+    HAL_CMD_MEASUREMENT= 0x76,
+    HAL_CMD_NAVIGATION= 0x77,
+    HAL_CMD_SWITCH_AGPS_DEBUG_DONE = 0x44,
+    HAL_CMD_SWITCH_AGPS_DEBUG_FAIL = 0X45,
+};
+
+
+
+#define M_START 0
+#define M_STOP 1
+#define M_CLEANUP 2
+#define M_INIT 3
+#define M_THREAD_EXIT 4
+#define M_MNLDIE 5
+typedef struct sync_lock
+{
+    pthread_mutex_t mutx;
+    pthread_cond_t con;
+    int condtion;
+}SYNC_LOCK_T;
+
+static SYNC_LOCK_T lock_for_sync[] = {{PTHREAD_MUTEX_INITIALIZER,PTHREAD_COND_INITIALIZER, 0},
+                                    {PTHREAD_MUTEX_INITIALIZER,PTHREAD_COND_INITIALIZER, 0},
+                                    {PTHREAD_MUTEX_INITIALIZER,PTHREAD_COND_INITIALIZER, 0},
+                                    {PTHREAD_MUTEX_INITIALIZER,PTHREAD_COND_INITIALIZER, 0},
+                                    {PTHREAD_MUTEX_INITIALIZER,PTHREAD_COND_INITIALIZER, 0},
+                                    {PTHREAD_MUTEX_INITIALIZER,PTHREAD_COND_INITIALIZER, 0}};
+
+const char* gps_native_thread = "GPS NATIVE THREAD";
+const char* gps_pmtk_thread = "GPS PMTK THREAD";
+const char* gps_nmea_read_thread = "GPS NMEA READ THREAD";
+const char* gps_send_epo_thread = "GPS SEND EPO THREAD";
+static GpsCallbacks callback_backup;
+static int start_flag = 0;
+static int g_delete_aiding_data_flag = 0;
+
+//for different SV parse
+typedef enum{
+    UNKNOWN_SV = 0,
+    GPS_SV,
+    GLONASS_SV,
+    BDS_SV,
+    GALILEO_SV,
+}SV_TYPE;
+static float report_time_interval = 0;
+static int started = 0;
+
+//#define  NMEA_MAX_SIZE  83
+#define  NMEA_MAX_SIZE  255
+/*maximum number of SV information in GPGSV*/
+#define  NMEA_MAX_SV_INFO 4
+#define  LOC_FIXED(pNmeaReader) ((pNmeaReader->fix_mode == 2) || (pNmeaReader->fix_mode ==3))
+typedef struct {
+    int     pos;
+    int     overflow;
+    int     utc_year;
+    int     utc_mon;
+    int     utc_day;
+    int     utc_diff;
+    GpsLocation  fix;
+
+    /*
+     * The fix flag extracted from GPGSA setence: 1: No fix; 2 = 2D; 3 = 3D
+     * if the fix mode is 0, no location will be reported via callback
+     * otherwise, the location will be reported via callback
+     */
+    int     fix_mode;
+    /*
+     * Indicate that the status of callback handling.
+     * The flag is used to report GPS_STATUS_SESSION_BEGIN or GPS_STATUS_SESSION_END:
+     * (0) The flag will be set as true when callback setting is changed via nmea_reader_set_callback
+     * (1) GPS_STATUS_SESSION_BEGIN: receive location fix + flag set + callback is set
+     * (2) GPS_STATUS_SESSION_END:   receive location fix + flag set + callback is null
+     */
+    int     cb_status_changed;
+    int     sv_count;           /*used to count the number of received SV information*/
+    GnssSvStatus  sv_status;
+    GpsCallbacks callbacks;
+    char    in[ NMEA_MAX_SIZE + 1 ];
+} NmeaReader;
+
+typedef struct {
+    pthread_t               thread;
+    int                     server_fd;
+}PMTKThread;
+
+/* this is the state of our connection to the daemon */
+typedef struct {
+    int                     init;  // to check whether, have been initialized
+    int                     pow_fd; //power ctrl
+    int                     tty_fd; //for read nmea
+    GpsCallbacks            callbacks; // up layer callback
+    pthread_t               thread;
+    PMTKThread              pmtk_thread[1];
+    pthread_t               nmea_read_thread;
+    int                     control[2];
+    int                     test_time;
+    int                     epoll_hd;
+    int                     flag;
+    int                     start_flag;
+} GpsState;
+
+static GpsState  _gps_state[1];
+
+/*****************************************************************/
+/*****************************************************************/
+/*****                                                       *****/
+/*****       C O N N E C T I O N   S T A T E                 *****/
+/*****                                                       *****/
+/*****************************************************************/
+/*****************************************************************/
+
+/* commands sent to the gps thread */
+enum {
+    CMD_QUIT  = 0,
+    CMD_START = 1,
+    CMD_STOP  = 2,
+    CMD_RESTART = 3,
+    CMD_DOWNLOAD = 4,
+
+    CMD_TEST_START = 10,
+    CMD_TEST_STOP = 11,
+    CMD_TEST_SMS_NO_RESULT = 12,
+    CMD_EPO_DOWNLOAD_DONE = 13,
+};
+
+
+static int gps_nmea_end_tag = 0;
+
+int sv_used_in_fix[256] = {0};    // for multiple sv display
+
+unsigned char calc_nmea_checksum( const char* sentence);
+void send_assistance_data (int iYr, int iMo, int iDay, int iHr, char * timeInfo, int iTimeLen);
+
+static void get_condition(SYNC_LOCK_T *lock)
+{
+    int ret = 0;
+
+    ret = pthread_mutex_lock(&(lock->mutx));
+    DBG("ret get_mutex lock = %d\n",ret);
+
+    while (!lock->condtion)
+    {
+        DBG("ret get_cond wait = %d\n" ,ret);
+        ret = pthread_cond_wait(&(lock->con), &(lock->mutx));
+    }
+
+    lock->condtion = 0;
+    DBG("ret get_mutex unlock = %d\n",ret);
+    ret = pthread_mutex_unlock(&(lock->mutx));
+    DBG("test");
+
+    return;
+}
+
+static void release_condition(SYNC_LOCK_T *lock)
+{
+    int ret = 0;
+
+
+    ret = pthread_mutex_lock(&(lock->mutx));
+    DBG("ret release_mutex lock = %d\n",ret);
+
+    lock->condtion= 1;
+    ret = pthread_cond_signal(&(lock->con));
+    DBG ("ret release_cond_signal = %d\n",ret);
+
+    ret = pthread_mutex_unlock(&(lock->mutx));
+    DBG("ret release_unlock= %d\n",ret);
+
+    return;
+}
+
+int mtk_restart(unsigned char cmd)
+{
+    char buf[] = {cmd};
+    TRC();
+    return 0;
+}
+
+/*****************************************************************/
+/*****************************************************************/
+/*****                                                       *****/
+/*****       N M E A   T O K E N I Z E R                     *****/
+/*****                                                       *****/
+/*****************************************************************/
+/*****************************************************************/
+
+typedef struct {
+    const char*  p;
+    const char*  end;
+} Token;
+
+#define  MAX_NMEA_TOKENS  24
+
+typedef struct {
+    int     count;
+    Token   tokens[ MAX_NMEA_TOKENS ];
+} NmeaTokenizer;
+
+static int
+nmea_tokenizer_init( NmeaTokenizer*  t, const char*  p, const char*  end ) {
+    int    count = 0;
+    char*  q;
+
+    // the initial '$' is optional
+    if (p < end && p[0] == '$')
+        p += 1;
+
+    // remove trailing newline
+    if (end > p && end[-1] == '\n') {
+        end -= 1;
+        if (end > p && end[-1] == '\r')
+            end -= 1;
+    }
+
+    // get rid of checksum at the end of the sentecne
+    if (end >= p+3 && end[-3] == '*') {
+        end -= 3;
+    }
+
+    while (p < end) {
+        const char*  q = p;
+
+        q = memchr(p, ',', end-p);
+        if (q == NULL)
+            q = end;
+
+        if (q >= p) {
+            if (count < MAX_NMEA_TOKENS) {
+                t->tokens[count].p   = p;
+                t->tokens[count].end = q;
+                count += 1;
+            }
+        }
+        if (q < end)
+            q += 1;
+
+        p = q;
+    }
+
+    t->count = count;
+    DBG(" t->count is %d", t->count);
+    return count;
+}
+
+static Token
+nmea_tokenizer_get( NmeaTokenizer*  t, int  index )
+{
+    Token  tok;
+    static const char*  dummy = "";
+
+    if (index < 0 || index >= t->count) {
+        tok.p = tok.end = dummy;
+    } else
+        tok = t->tokens[index];
+
+    return tok;
+}
+
+
+static int
+str2int( const char*  p, const char*  end )
+{
+    int   result = 0;
+    int   len    = end - p;
+    int   sign = 1;
+
+    if (*p == '-')
+    {
+        sign = -1;
+        p++;
+        len = end - p;
+    }
+
+    for ( ; len > 0; len--, p++ )
+    {
+        int  c;
+
+        if (p >= end)
+            goto Fail;
+
+        c = *p - '0';
+        if ((unsigned)c >= 10)
+            goto Fail;
+
+        result = result*10 + c;
+    }
+    return  sign*result;
+
+Fail:
+    return -1;
+}
+
+static double
+str2float( const char*  p, const char*  end )
+{
+    int   result = 0;
+    int   len    = end - p;
+    char  temp[16];
+
+    if (len >= (int)sizeof(temp))
+        return 0.;
+
+    memcpy( temp, p, len );
+    temp[len] = 0;
+    return strtod( temp, NULL );
+}
+
+static void mtk_gps_update_location(nlp_context * location)
+{
+    FILE *fp = NULL;
+
+    fp = fopen(LOCATION_NLP_FIX, "w");
+    if (fp != NULL)
+    {
+        size_t count = 0;
+        count = fwrite(location, sizeof(nlp_context), 1, fp);
+        if (count != 1)
+        {
+            DBG("write count:%d, errno:%s\n", count, strerror(errno));
+        }
+        fclose(fp);
+    }
+}
+
+static bool g_EpoSend = false;
+static void mtk_gps_send_EPO()
+{
+    time_t timep;
+    struct tm* pq;
+    time(&timep);
+    pq = gmtime(&timep);
+    char strBuf[200], outBuf[200];
+    memset(strBuf, 0, sizeof(strBuf));
+    memset(outBuf, 0, sizeof(outBuf));
+    sprintf(strBuf, "PMTK740,%d,%d,%d,%d,%d,%d",pq->tm_year + 1900, pq->tm_mon + 1, pq->tm_mday, pq->tm_hour, pq->tm_min, pq->tm_sec);
+    sprintf(outBuf, "$%s*%02X\r\n", strBuf, calc_nmea_checksum(strBuf));
+    DBG("final PMTK is %s, size is %d, len is %d", outBuf, sizeof(outBuf), strlen(outBuf));
+    send_assistance_data(pq->tm_year + 1900, pq->tm_mon + 1, pq->tm_mday, pq->tm_hour, outBuf, strlen(outBuf));
+}
+
+/*****************************************/
+/*****************************************/
+/*****                                                       *****/
+/*****       PowerGPS PMTK handle                 *****/
+/*****                                                       *****/
+/****************************************/
+/****************************************/
+
+static bool g_ThreadExitPMTKIn = false;//flag for PowerGPS thread exist
+static int g_hPowerGPS = INVALID_FD;//PowerGPS socket handle
+static NmeaReader  g_NmeaReader[1];
+
+/***************Receive From PowerGPS********************/
+void * pmtk_input_func(void * arg)
+{
+    int bytes = 0;
+    int ret = 0;
+    char pmtk_buf[200];
+    char  cmd = CMD_RESTART;
+    GpsState*   state = (GpsState*) arg;
+
+    while(g_ThreadExitPMTKIn)
+    {
+        memset(pmtk_buf, 0, sizeof(pmtk_buf));
+        bytes = read(g_hPowerGPS, pmtk_buf, 200);
+
+        if (bytes > 0)
+        {
+            DBG("!!!!!!!!!! PowerGPS pass : %s, lenth is %d", pmtk_buf, bytes);
+
+            do {
+                ret=write( state->control[0], &cmd, 1);
+            }
+            while (ret < 0 && errno == EINTR);
+            do {
+                ret=write( state->tty_fd, pmtk_buf, bytes);
+            }while (ret < 0 && errno == EINTR);
+            if (ret < 0)
+                DBG("!!!!!!!!!!!PowerGPS write FAIL, errno is %d  (%s)", errno, strerror(errno));
+            else
+                DBG("!!!!!!!!!!!!!!PowerGPS write succeed, ret is %d", ret);
+            if (strstr(pmtk_buf, "PMTK101")
+                || strstr(pmtk_buf, "PMTK102")
+                || strstr(pmtk_buf, "PMTK103")
+                || strstr(pmtk_buf, "PMTK104"))
+            {
+                g_EpoSend = true;
+                DBG("!!!!!!!PowerGPS got A START %s", pmtk_buf);
+            }
+        }
+        else
+        {
+            if (bytes == 0)
+            { //client close
+                DBG("!!!!!!socket client close");
+                break;
+            }
+            else
+            {
+                usleep(200000);  // sleep 200 ms
+                DBG("!!!!!!socket error = %d (%s)\r\n", errno, strerror(errno));
+            }
+        }
+    }
+    return NULL;
+}
+
+/***************Output To PowerGPS********************/
+void pmtk_output_func(char * buf, int * length)
+{
+    if (buf[(*length) - 2] != '\r'){
+        buf[(*length) - 1] = '\r';
+        buf[(*length)] = '\n';
+        (*length) += 1;
+    }
+    int len = (*length);
+    int ret = 0;
+    int written = 0;
+    int retry = 0;
+    if (g_hPowerGPS != INVALID_FD)
+    {
+        while( (written != len) && (retry <5))
+        {
+            ret = write(g_hPowerGPS, buf + written, len - written);
+            if (ret < 0)
+            {
+                retry++;
+            }
+            else
+            {
+                written += ret;
+            }
+        }
+    }
+}
+
+void powergps_thread_exit(int sig_no, int server_fd)
+{
+    if(server_fd != INVALID_SOCKET)
+    {
+        close(server_fd);
+        server_fd == INVALID_SOCKET;
+    }
+    pthread_exit((void *)0);
+}
+
+void signal_action_handle(int signum, siginfo_t * info, void *myact)
+{
+    DBG("######got Signal : %d", signum);
+}
+
+/*
+ *Create Socket Server to listen PMTK from PowerGPS
+ */
+void* powergps_pmtk_receive_thread( void*  arg )
+{
+    TRC();
+    g_ThreadExitPMTKIn = true;
+    GpsState*   state = (GpsState*) arg;
+    int server_fd = state->pmtk_thread->server_fd;
+
+    int conn_fd = INVALID_SOCKET, on;
+    struct sockaddr_in server_addr;
+    struct sockaddr_in client_addr;
+    socklen_t size;
+    int hdlsig = SIGUSR1;
+    struct sigaction sa;
+    char buf[128];
+
+    if ((server_fd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
+    {
+        DBG("socket error = %d (%s)\r\n", errno, strerror(errno));
+        pthread_exit((void *)0);
+        return NULL;
+    }
+    DBG("########### socket create SUCCESS - pid == %d, fd == %d", getpid(), server_fd);
+
+    /* Enable address reuse */
+    on = 1;
+    if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)))
+    {
+        close(server_fd);
+        pthread_exit((void *)0);
+        return NULL;
+    }
+    DBG("########### socket set SUCCESS");
+
+    server_addr.sin_family = AF_INET;   /*host byte order*/
+    server_addr.sin_port = htons(PMTK_SOCKET_COM_PORT); /*short, network byte order*/
+    server_addr.sin_addr.s_addr = htonl(INADDR_ANY); /*automatically fill with my IP*/
+    memset(server_addr.sin_zero, 0x00, sizeof(server_addr.sin_zero));
+
+    if (bind(server_fd, (struct sockaddr*)&server_addr, sizeof(server_addr)) == -1)
+    {
+        close(server_fd);
+        pthread_exit((void *)0);
+        return NULL;
+    }
+    DBG("########### socket bind SUCCESS");
+
+    if (listen(server_fd, PMTK_SERVER_BACKLOG) == -1)
+    {
+        close(server_fd);
+        pthread_exit((void *)0);
+        return NULL;
+    }
+    DBG("########### socket listen SUCCESS");
+
+    sa.sa_handler = SIG_IGN;
+    sa.sa_sigaction = signal_action_handle;
+    sa.sa_flags = (0 | SA_SIGINFO);
+    sigemptyset(&sa.sa_mask);
+   if (sigaction(SIGPIPE, &sa, NULL) < 0)
+    {
+        DBG("sigaction error \r\n");
+    }
+
+    while (g_ThreadExitPMTKIn)
+    {
+        size = sizeof(client_addr);
+        DBG("########### waiting the client..........");
+        conn_fd = accept(server_fd, (struct sockaddr*)&client_addr, &size);
+        DBG("########### client comes in..........");
+
+        if (conn_fd <= 0)
+        {
+            DBG("######### no client");
+            close(server_fd);
+            break;
+        }
+        else
+        {
+            g_hPowerGPS = conn_fd;
+            pmtk_input_func(state);
+        }
+    }
+    powergps_thread_exit(0, server_fd);//call pthread_exit() in this function, the code after this sentence will not be executed
+    return NULL;
+}
+
+/*****************************************************************/
+/*****************************************************************/
+/*****                                                       *****/
+/*****       N M E A   P A R S E R                           *****/
+/*****                                                       *****/
+/*****************************************************************/
+/*****************************************************************/
+
+static void
+nmea_reader_update_utc_diff( NmeaReader* const r )
+{
+    time_t         now = time(NULL);
+    struct tm      tm_local;
+    struct tm      tm_utc;
+    unsigned long  time_local, time_utc;
+
+    gmtime_r( &now, &tm_utc );
+    localtime_r( &now, &tm_local );
+
+    time_local = mktime(&tm_local);
+    time_utc = mktime(&tm_utc);
+    r->utc_diff = time_utc - time_local;
+}
+
+
+static void
+nmea_reader_init( NmeaReader* const r )
+{
+    memset( r, 0, sizeof(*r) );
+
+    r->pos      = 0;
+    r->overflow = 0;
+    r->utc_year = -1;
+    r->utc_mon  = -1;
+    r->utc_day  = -1;
+    r->utc_diff = 0;
+    r->callbacks.location_cb= NULL;
+    r->callbacks.status_cb= NULL;
+    r->callbacks.gnss_sv_status_cb= NULL;
+    r->sv_count = 0;
+    r->fix_mode = 0;    /*no fix*/
+    r->cb_status_changed = 0;
+    memset((void*)&r->sv_status, 0x00, sizeof(r->sv_status));
+    memset((void*)&r->in, 0x00, sizeof(r->in));
+
+    nmea_reader_update_utc_diff( r );
+    r->fix.flags |= GPS_LOCATION_HAS_ACCURACY;
+    r->fix.accuracy = 10;
+}
+
+static void
+nmea_reader_set_callback( NmeaReader* const r, GpsCallbacks* const cbs)
+{
+    if (!r) {           /*this should not happen*/
+        return;
+    } else if (!cbs) {  /*unregister the callback */
+        return ;
+    } else {/*register the callback*/
+        r->sv_count = r->sv_status.num_svs = 0;
+        r->fix.flags |= GPS_LOCATION_HAS_ACCURACY;
+        r->fix.accuracy = 10;
+    }
+}
+
+
+static int
+nmea_reader_update_time( NmeaReader* const r, Token  tok ) {
+    int        hour, minute;
+    double     seconds;
+    struct tm  tm;
+    time_t     fix_time;
+
+    if (tok.p + 6 > tok.end)
+        return -1;
+
+    memset((void*)&tm, 0x00, sizeof(tm));
+    if (r->utc_year < 0) {
+        // no date yet, get current one
+        time_t  now = time(NULL);
+        gmtime_r( &now, &tm );
+        r->utc_year = tm.tm_year + 1900;
+        r->utc_mon  = tm.tm_mon + 1;
+        r->utc_day  = tm.tm_mday;
+    }
+
+    hour    = str2int(tok.p,   tok.p+2);
+    minute  = str2int(tok.p+2, tok.p+4);
+    seconds = str2float(tok.p+4, tok.end);
+
+    tm.tm_hour = hour;
+    tm.tm_min  = minute;
+    tm.tm_sec  = (int) seconds;
+    tm.tm_year = r->utc_year - 1900;
+    tm.tm_mon  = r->utc_mon - 1;
+    tm.tm_mday = r->utc_day;
+    tm.tm_isdst = -1;
+
+    if (mktime(&tm) == (time_t)-1)
+        ERR("mktime error: %d %s\n", errno, strerror(errno));
+
+    nmea_reader_update_utc_diff(r);
+
+    fix_time = mktime(&tm) - r->utc_diff;
+    DBG("fix_time: %d\n",fix_time);
+    r->fix.timestamp = (long long)fix_time * 1000;
+    return 0;
+}
+
+static int
+nmea_reader_update_date( NmeaReader* const r, Token  date, Token  time )
+{
+    Token  tok = date;
+    int    day, mon, year;
+
+    if (tok.p + 6 != tok.end) {
+        ERR("date not properly formatted: '%.*s'", tok.end-tok.p, tok.p);
+        return -1;
+    }
+    day  = str2int(tok.p, tok.p+2);
+    mon  = str2int(tok.p+2, tok.p+4);
+    year = str2int(tok.p+4, tok.p+6) + 2000;
+
+    if ((day|mon|year) < 0) {
+        ERR("date not properly formatted: '%.*s'", tok.end-tok.p, tok.p);
+        return -1;
+    }
+
+    r->utc_year  = year;
+    r->utc_mon   = mon;
+    r->utc_day   = day;
+
+    return nmea_reader_update_time( r, time );
+}
+
+
+static double
+convert_from_hhmm( Token  tok )
+{
+    double  val     = str2float(tok.p, tok.end);
+    int     degrees = (int)(floor(val) / 100);
+    double  minutes = val - degrees*100.;
+    double  dcoord  = degrees + minutes / 60.0;
+    return dcoord;
+}
+
+
+static int
+nmea_reader_update_latlong( NmeaReader* const r,
+                            Token        latitude,
+                            char         latitudeHemi,
+                            Token        longitude,
+                            char         longitudeHemi ) {
+    double   lat, lon;
+    Token    tok;
+
+    tok = latitude;
+    if (tok.p + 6 > tok.end) {
+        return -1;
+    }
+    lat = convert_from_hhmm(tok);
+    if (latitudeHemi == 'S')
+        lat = -lat;
+
+    tok = longitude;
+    if (tok.p + 6 > tok.end) {
+        return -1;
+    }
+    lon = convert_from_hhmm(tok);
+    if (longitudeHemi == 'W')
+        lon = -lon;
+
+    r->fix.flags    |= GPS_LOCATION_HAS_LAT_LONG;
+    r->fix.latitude  = lat;
+    r->fix.longitude = lon;
+    return 0;
+}
+
+static int
+nmea_reader_update_altitude( NmeaReader* const r,
+                             Token        altitude,
+                             Token        units ) {
+    double  alt;
+    Token   tok = altitude;
+
+    if (tok.p >= tok.end)
+        return -1;
+
+    r->fix.flags   |= GPS_LOCATION_HAS_ALTITUDE;
+    r->fix.altitude = str2float(tok.p, tok.end);
+    return 0;
+}
+
+
+static int
+nmea_reader_update_bearing( NmeaReader* const r,
+                            Token        bearing )
+{
+    double  alt;
+    Token   tok = bearing;
+
+    if (tok.p >= tok.end)
+        return -1;
+
+    r->fix.flags   |= GPS_LOCATION_HAS_BEARING;
+    r->fix.bearing  = str2float(tok.p, tok.end);
+    return 0;
+}
+
+
+static int
+nmea_reader_update_speed( NmeaReader* const r,
+                          Token        speed )
+{
+    double  alt;
+    Token   tok = speed;
+
+    if (tok.p >= tok.end)
+        return -1;
+
+    r->fix.flags   |= GPS_LOCATION_HAS_SPEED;
+
+    //Modify by ZQH to convert the speed unit from knot to m/s
+    //r->fix.speed    = str2float(tok.p, tok.end);
+    r->fix.speed = str2float(tok.p, tok.end) / 1.942795467;
+    return 0;
+}
+
+//Add by LCH for accuracy
+static int
+nmea_reader_update_accuracy( NmeaReader* const r,
+                             Token accuracy )
+{
+    double  alt;
+    Token   tok = accuracy;
+
+    if (tok.p >= tok.end)
+        return -1;
+
+    r->fix.flags   |= GPS_LOCATION_HAS_ACCURACY;
+    r->fix.accuracy = str2float(tok.p, tok.end);
+    return 0;
+}
+
+static int
+nmea_reader_update_sv_status( NmeaReader* r, int sv_index,
+                              int id, Token elevation,
+                              Token azimuth, Token snr)
+{
+    //int prn = str2int(id.p, id.end);
+    int prn = id;
+
+    if ((prn <= 0) || (prn < 65 && prn > GPS_MAX_SVS)|| ((prn > 96) && (prn < 200)) || (prn > 232) || (r->sv_count >= GNSS_MAX_SVS)) {
+        VER("sv_status: ignore (%d)", prn);
+        return 0;
+    }
+    sv_index = r->sv_count+r->sv_status.num_svs;
+    if(GNSS_MAX_SVS <= sv_index)
+    {
+        ERR("ERR: sv_index=[%d] is larger than GNSS_MAX_SVS.\n", sv_index);
+        return 0;
+    }
+
+    if ((prn > 0) && (prn < 32)) {
+        r->sv_status.gnss_sv_list[sv_index].svid = prn;
+        r->sv_status.gnss_sv_list[sv_index].constellation = GPS_SV;
+    } else if ((prn >= 65) && (prn <= 96)) {
+        r->sv_status.gnss_sv_list[sv_index].svid = prn-64;
+        r->sv_status.gnss_sv_list[sv_index].constellation = GLONASS_SV;
+    } else if ((prn >= 201) && (prn <= 237)) {
+        r->sv_status.gnss_sv_list[sv_index].svid = prn-200;
+        r->sv_status.gnss_sv_list[sv_index].constellation = BDS_SV;
+    } else if ((prn >= 401) && (prn <= 436)) {
+        r->sv_status.gnss_sv_list[sv_index].svid = prn-400;
+        r->sv_status.gnss_sv_list[sv_index].constellation = GALILEO_SV;
+    } else {
+        DBG("sv_status: ignore (%d)", prn);
+        return 0;
+    }
+
+    r->sv_status.gnss_sv_list[sv_index].c_n0_dbhz = str2float(snr.p, snr.end);
+    r->sv_status.gnss_sv_list[sv_index].elevation = str2int(elevation.p, elevation.end);
+    r->sv_status.gnss_sv_list[sv_index].azimuth = str2int(azimuth.p, azimuth.end);
+    if(1 == sv_used_in_fix[prn]){
+        r->sv_status.gnss_sv_list[sv_index].flags |= 0x04;;
+    }else{
+        r->sv_status.gnss_sv_list[sv_index].flags &= 0xFB;
+    }
+    r->sv_count++;
+    DBG("sv_status(%2d): %2d, %d, %2f, %3f, %2f, %d",
+        sv_index, r->sv_status.gnss_sv_list[sv_index].svid, r->sv_status.gnss_sv_list[sv_index].constellation,
+        r->sv_status.gnss_sv_list[sv_index].elevation, r->sv_status.gnss_sv_list[sv_index].azimuth,
+        r->sv_status.gnss_sv_list[sv_index].c_n0_dbhz, r->sv_status.gnss_sv_list[sv_index].flags);
+    return 0;
+}
+
+static int
+nmea_reader_parse( NmeaReader* const r )
+{
+   /* we received a complete sentence, now parse it to generate
+    * a new GPS fix...
+    */
+    NmeaTokenizer  tzer[1];
+    Token          tok;
+    Token          mtok;
+    SV_TYPE sv_type = 0;
+
+  /*
+    if (r->pos < 9) {
+        ERR("Too short. discarded. '%.*s'", r->pos, r->in);
+        return;
+    }
+    */
+
+    nmea_tokenizer_init(tzer, r->in, r->in + r->pos);
+
+#if NEMA_DEBUG
+    {
+        int  n;
+        DBG("Found %d tokens", tzer->count);
+        for (n = 0; n < tzer->count; n++) {
+            Token  tok = nmea_tokenizer_get(tzer,n);
+            DBG("%2d: '%.*s'", n, tok.end-tok.p, tok.p);
+        }
+    }
+#endif
+
+    tok = nmea_tokenizer_get(tzer, 0);
+    if (tok.p + 5 > tok.end) {
+        ERR("sentence id '%.*s' too short, ignored.", tok.end-tok.p, tok.p);
+        return -1;
+    }
+
+    // ignore first two characters.
+    mtok.p = tok.p; //Mark the first two char for GPS,GLONASS,BDS SV parse.
+    if(!memcmp(mtok.p, "BD", 2)){
+        sv_type = BDS_SV;
+        DBG("BDS SV type");
+    } else if (!memcmp(mtok.p, "GP", 2)) {
+        sv_type = GPS_SV;
+    } else if (!memcmp(mtok.p, "GL", 2)) {
+        sv_type = GLONASS_SV;
+    } else if (!memcmp(mtok.p, "GA", 2)) {
+        sv_type = GALILEO_SV;
+    }
+    #if NEMA_DEBUG
+    LOGD("SV type: %d", sv_type);
+    #endif
+    tok.p += 2;
+    if ( !memcmp(tok.p, "GGA", 3) )
+    {
+        if (tzer->count < 14)
+            return 0;
+        // GPS fix
+        Token  tok_time          = nmea_tokenizer_get(tzer,1);
+        Token  tok_latitude      = nmea_tokenizer_get(tzer,2);
+        Token  tok_latitudeHemi  = nmea_tokenizer_get(tzer,3);
+        Token  tok_longitude     = nmea_tokenizer_get(tzer,4);
+        Token  tok_longitudeHemi = nmea_tokenizer_get(tzer,5);
+        Token  tok_altitude      = nmea_tokenizer_get(tzer,9);
+        Token  tok_altitudeUnits = nmea_tokenizer_get(tzer,10);
+
+        nmea_reader_update_time(r, tok_time);
+        nmea_reader_update_latlong(r, tok_latitude,
+                                      tok_latitudeHemi.p[0],
+                                      tok_longitude,
+                                      tok_longitudeHemi.p[0]);
+        nmea_reader_update_altitude(r, tok_altitude, tok_altitudeUnits);
+
+    }
+    else if ( !memcmp(mtok.p, "GPGSA", 5)||!memcmp(mtok.p, "BDGSA", 5)||!memcmp(mtok.p, "GLGSA", 5)) {
+        if (tzer->count < 18)
+            return 0;
+        Token tok_fix = nmea_tokenizer_get(tzer, 2);
+        int idx, max = 12; /*the number of satellites in GPGSA*/
+
+        r->fix_mode = str2int(tok_fix.p, tok_fix.end);
+
+        if (LOC_FIXED(r)) { /* 1: No fix; 2: 2D; 3: 3D*/
+            for (idx = 0; idx < max; idx++) {
+                Token tok_satellite = nmea_tokenizer_get(tzer, idx+3);
+                if (tok_satellite.p == tok_satellite.end) {
+                    break;
+                }
+                int sate_id = str2int(tok_satellite.p, tok_satellite.end);
+                if (sv_type == BDS_SV){
+                    sate_id += 200;
+                }
+                if (sate_id >= 1 && sate_id <= 32) {  //GP
+                    sv_used_in_fix[sate_id] = 1;
+                }else if(sate_id >= 193 && sate_id <= 197){
+                    sv_used_in_fix[sate_id] = 0;
+                    continue;
+                }else if(sate_id >= 65 && sate_id <= 96){  //GL
+                    sv_used_in_fix[sate_id] = 1;
+                }else if(sate_id >= 201 && sate_id <= 232){  //BD
+                    sv_used_in_fix[sate_id] = 1;
+
+                }
+                else{
+                    break;
+                }
+            }
+        }
+    }
+ //VER("GPGSA: mask 0x%x", r->sv_status.used_in_fix_mask);
+    else if ( !memcmp(tok.p, "RMC", 3) ) {
+        if (tzer->count < 13)
+            return 0;
+        Token  tok_time          = nmea_tokenizer_get(tzer,1);
+        Token  tok_fixStatus     = nmea_tokenizer_get(tzer,2);
+        Token  tok_latitude      = nmea_tokenizer_get(tzer,3);
+        Token  tok_latitudeHemi  = nmea_tokenizer_get(tzer,4);
+        Token  tok_longitude     = nmea_tokenizer_get(tzer,5);
+        Token  tok_longitudeHemi = nmea_tokenizer_get(tzer,6);
+        Token  tok_speed         = nmea_tokenizer_get(tzer,7);
+        Token  tok_bearing       = nmea_tokenizer_get(tzer,8);
+        Token  tok_date          = nmea_tokenizer_get(tzer,9);
+
+        if (tok_fixStatus.p[0] == 'A') {
+            nmea_reader_update_date( r, tok_date, tok_time );
+            nmea_reader_update_latlong( r, tok_latitude,
+                    tok_latitudeHemi.p[0],
+                    tok_longitude,
+                    tok_longitudeHemi.p[0] );
+            nmea_reader_update_bearing( r, tok_bearing );
+            nmea_reader_update_speed( r, tok_speed );
+        }
+    }
+    else if ( !memcmp(tok.p, "GSV", 3) ) {
+        if (tzer->count < 4)
+            return 0;
+        Token tok_num = nmea_tokenizer_get(tzer,1); //number of messages
+        Token tok_seq = nmea_tokenizer_get(tzer,2); //sequence number
+        Token tok_cnt = nmea_tokenizer_get(tzer,3); //Satellites in view
+        int num = str2int(tok_num.p, tok_num.end);
+        int seq = str2int(tok_seq.p, tok_seq.end);
+        int cnt = str2int(tok_cnt.p, tok_cnt.end);
+        int sv_base = (seq - 1)*NMEA_MAX_SV_INFO;
+        int sv_num = cnt - sv_base;
+        int idx, base = 4, base_idx;
+        if (sv_num > NMEA_MAX_SV_INFO)
+            sv_num = NMEA_MAX_SV_INFO;
+        if (seq == 1)   /*if sequence number is 1, a new set of GSV will be parsed*/
+            r->sv_count = 0;
+        for (idx = 0; idx < sv_num; idx++) {
+            base_idx = base*(idx+1);
+            Token tok_id  = nmea_tokenizer_get(tzer, base_idx+0);
+            int sv_id = str2int(tok_id.p, tok_id.end);
+            if (sv_type == BDS_SV)
+                sv_id += 200;
+            else if (sv_type == GALILEO_SV)
+                sv_id += 400;
+            Token tok_ele = nmea_tokenizer_get(tzer, base_idx+1);
+            Token tok_azi = nmea_tokenizer_get(tzer, base_idx+2);
+            Token tok_snr = nmea_tokenizer_get(tzer, base_idx+3);
+            nmea_reader_update_sv_status(r, sv_base+idx, sv_id, tok_ele, tok_azi, tok_snr);
+        }
+        if (seq == num) {
+            if (r->sv_count <= cnt) {
+                r->sv_status.num_svs += r->sv_count;
+            }
+            else {
+                ERR("GPGSV incomplete (%d/%d), ignored!", r->sv_count, cnt);
+                r->sv_count = r->sv_status.num_svs = 0;
+            }
+        }
+    }
+    //Add for Accuracy
+    else if ( !memcmp(tok.p, "ACCURACY", 8)) {
+        if((r->fix_mode == 3)||(r->fix_mode == 2)) {
+            Token  tok_accuracy = nmea_tokenizer_get(tzer,1);
+            nmea_reader_update_accuracy(r, tok_accuracy);
+        }
+    }
+    else if ( !(memcmp(mtok.p, "GPBOD", 5)
+              && memcmp(mtok.p, "GPBWC", 5)
+              && memcmp(mtok.p, "GPGLL", 5)
+              && memcmp(mtok.p, "GPHDT", 5)
+              && memcmp(mtok.p, "GPROO", 5)
+              && memcmp(mtok.p, "GPRMA", 5)
+              && memcmp(mtok.p, "GPRMB", 5)
+              && memcmp(mtok.p, "GPRTE", 5)
+              && memcmp(mtok.p, "GPTRF", 5)
+              && memcmp(mtok.p, "GPSTN", 5)
+              && memcmp(mtok.p, "GPVBW", 5)
+              && memcmp(mtok.p, "GPVTG", 5)
+              && memcmp(mtok.p, "GPWPL", 5)
+              && memcmp(mtok.p, "GPXTE", 5)
+              && memcmp(mtok.p, "GPZDA", 5)))
+    {
+        tok.p -= 2;
+    }
+    else if ( !memcmp(mtok.p, "PMTK", 4))
+    {
+        tok.p -=2;
+        DBG("PMTK is %s", r->in);
+        if ( !memcmp(mtok.p, "PMTK010,002", 11) && g_EpoSend)
+        {
+            DBG("we got some START, ready to send EPO data");
+            callback_backup.create_thread_cb(gps_send_epo_thread, mtk_gps_send_EPO, NULL);
+            g_EpoSend = false;
+        }
+		/* disable QZSS start */
+        else if ( !memcmp(mtok.p, "PMTK010,001", 11))
+        {
+            DBG("we got some START, ready to send 352 cmd");
+			int temp_ret = 0;
+            temp_ret = write(_gps_state->tty_fd, "$PMTK352,1*2B\r\n", 15);
+			DBG("hao test : temp_ret is %d", temp_ret);
+            //g_EpoSend = false;
+        }
+        else if ( !memcmp(mtok.p, "PMTK001,352,3", 13))
+        {
+            DBG("received 352,3 response");
+        }
+        /* disable QZSS end */
+        return 0;
+    }
+    else {
+        tok.p -= 2;
+        return 0;
+    }
+    if (!LOC_FIXED(r)) {
+        VER("Location is not fixed, ignored callback\n");
+    }
+    else if (r->fix.flags != 0 && gps_nmea_end_tag) {
+#if NEMA_DEBUG
+        char   temp[256];
+        char*  p   = temp;
+        char*  end = p + sizeof(temp);
+        struct tm   utc;
+
+        p += snprintf( p, end-p, "sending fix" );
+        if (r->fix.flags & GPS_LOCATION_HAS_LAT_LONG) {
+            p += snprintf(p, end-p, " lat=%g lon=%g", r->fix.latitude, r->fix.longitude);
+        }
+        if (r->fix.flags & GPS_LOCATION_HAS_ALTITUDE) {
+            p += snprintf(p, end-p, " altitude=%g", r->fix.altitude);
+        }
+        if (r->fix.flags & GPS_LOCATION_HAS_SPEED) {
+            p += snprintf(p, end-p, " speed=%g", r->fix.speed);
+        }
+        if (r->fix.flags & GPS_LOCATION_HAS_BEARING) {
+            p += snprintf(p, end-p, " bearing=%g", r->fix.bearing);
+        }
+        if (r->fix.flags & GPS_LOCATION_HAS_ACCURACY) {
+            p += snprintf(p,end-p, " accuracy=%g", r->fix.accuracy);
+            DBG("GPS accuracy=%g\n", r->fix.accuracy);
+        }
+        gmtime_r( (time_t*) &r->fix.timestamp, &utc );
+        p += snprintf(p, end-p, " time=%s", asctime( &utc ) );
+        VER(temp);
+#endif
+        callback_backup.location_cb(&r->fix);
+        {
+            nlp_context fix_location;
+            fix_location.latitude = r->fix.latitude;
+            fix_location.longitude= r->fix.longitude;
+            fix_location.accuracy= r->fix.accuracy;
+            fix_location.type = 1;
+            fix_location.started = started;
+            fix_location.ts.tv_sec = r->fix.timestamp/1000;
+            fix_location.ts.tv_nsec = (r->fix.timestamp%1000) * 1000*1000;
+            mtk_gps_update_location(&fix_location);
+        }
+        r->fix.flags = GPS_LOCATION_HAS_ACCURACY;
+    }
+
+    DBG("r->sv_status.num_svs = %d, gps_nmea_end_tag = %d", r->sv_status.num_svs,gps_nmea_end_tag);
+    if (r->sv_status.num_svs != 0 && gps_nmea_end_tag)
+    {
+        int idx;
+        r->sv_status.size = sizeof(GnssSvStatus);
+        callback_backup.gnss_sv_status_cb(&r->sv_status);
+        r->sv_count = r->sv_status.num_svs = 0;
+        memset( sv_used_in_fix, 0, 256*sizeof(int));
+    }
+    return 1;
+}
+
+
+static void
+nmea_reader_addc( NmeaReader* const r, int  c )
+{
+    int ret = 0;
+    if (r->overflow) {
+        r->overflow = (c != '\n');
+        return;
+    }
+
+    if (r->pos >= (int) sizeof(r->in)-1 ) {
+        r->overflow = 1;
+        r->pos      = 0;
+        DBG("nmea sentence overflow\n");
+        return;
+    }
+
+    r->in[r->pos] = (char)c;
+    r->pos       += 1;
+    //DBG(" r->in[%d] is %c, r->pos is %d", r->pos, r->in[r->pos], r->pos);
+    if (c == '\n')
+    {
+        //r->pos < 9 :too short
+        if (gps_nmea_end_tag == 1 && r->pos >= 9) {
+            ret = nmea_reader_parse( r );
+            if (ret == 1)
+            {
+                DBG("ready to send : %s, strlen is %d, sizeof is %d", r->in, strlen(r->in), sizeof(r->in));
+                callback_backup.nmea_cb( r->fix.timestamp, r->in, r->pos );
+                pmtk_output_func( r->in, &(r->pos));
+            }
+            if (ret == 0)
+            {
+                pmtk_output_func(r->in, &(r->pos));
+            }
+            r->pos = 0;
+        }
+        else {
+            r->pos -=1;
+        }
+    }
+}
+
+static int
+epoll_register( int  epoll_fd, int  fd )
+{
+    struct epoll_event  ev;
+    int                 ret, flags;
+
+    /* important: make the fd non-blocking */
+    flags = fcntl(fd, F_GETFL);
+    fcntl(fd, F_SETFL, flags | O_NONBLOCK);
+
+    ev.events  = EPOLLIN;
+    ev.data.fd = fd;
+    do {
+        ret = epoll_ctl( epoll_fd, EPOLL_CTL_ADD, fd, &ev );
+    } while (ret < 0 && errno == EINTR);
+    if(ret < 0)
+        ERR("epoll ctl error, error num is %d\n, message is %s\n", errno, strerror(errno));
+    return ret;
+}
+
+
+static int
+epoll_deregister( int  epoll_fd, int  fd )
+{
+    int  ret;
+    do {
+        ret = epoll_ctl( epoll_fd, EPOLL_CTL_DEL, fd, NULL );
+    } while (ret < 0 && errno == EINTR);
+    return ret;
+}
+
+void
+mtk_gps_start_driver()
+{
+    int fp = open("/dev/mt3337_gpsonly", O_RDWR);
+    if (fp == -1) {
+        DBG("open dev/mt3337_gpsonly fail, errorno is %d", errno);
+    }
+    else {
+        ioctl(fp, GPS_POWER_IOCTL, 1);
+        usleep(1000*200);
+        ioctl(fp, GPS_POWER_IOCTL, 0);
+        usleep(1000*200);
+        ioctl(fp, GPS_POWER_IOCTL, 1);
+    }
+    close(fp);
+}
+
+void
+mtk_gps_reset_driver()
+{
+    int fp = open("/dev/mt3337_gpsonly", O_RDWR);
+    if (fp == -1) {
+        DBG("open dev/mt3337_gpsonly fail, errorno is %d", errno);
+    }
+    else {
+        ioctl(fp, GPS_POWER_IOCTL, 0);
+        usleep(1000*1000);
+        ioctl(fp, GPS_POWER_IOCTL, 1);
+    }
+    close(fp);
+}
+
+void
+mtk_gps_stop_driver()
+{
+    int fp = open("/dev/mt3337_gpsonly", O_RDWR);
+    if (fp == -1) {
+        DBG("open dev/mt3337_gpsonly fail, errorno is %d", errno);
+    }
+    else {
+        ioctl(fp, GPS_POWER_IOCTL, 0);
+    }
+    close(fp);
+}
+
+void
+mnl_load_property()
+{
+    char result[512] = {0};
+    int iEpoDisable = 0;
+    int iHotstillEnable = 0;
+    GpsState*  s = _gps_state;
+    int ret = 0;
+    if (property_get(MNL_CONFIG_STATUS, result, NULL))
+    {
+        iEpoDisable = result[7] - '0';
+        if (iEpoDisable == 0)
+        {
+            ret = write(s->tty_fd, "$PMTK127*36\r\n", 13);
+            DBG("we r going to clear EPO data, ret is %d", ret);
+        }
+        iHotstillEnable = result[4] - '0';
+        if (iHotstillEnable == 1)
+        {
+            ret = write(s->tty_fd, "$PMTK869,1,1*35\r\n", 17);
+            DBG("we r going to enable easy, ret is %d", ret);
+        }
+        else
+        {
+            ret = write(s->tty_fd, "$PMTK869,1,0*36\r\n", 17);
+            DBG("we r going to disable easy, ret is %d", ret);
+        }
+    }
+    else
+    {
+        DBG("YGPS config not set yet");
+    }
+}
+
+unsigned char
+calc_nmea_checksum( const char* sentence)
+{
+    unsigned char checksum = 0;
+    while (*sentence)
+    {
+        checksum ^= (unsigned char)*sentence++;
+    }
+
+    return checksum;
+}
+
+//translate UTC to GPS_Hour
+int
+utc_to_gps_hour( int iYr, int iMo, int iDay, int iHr)
+{
+    int iYearsElapsed;
+    int iDaysElapsed;
+    int iLeapDays;
+    int i;
+
+    const unsigned short doy[12] = {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334};
+    iYearsElapsed = iYr - 1980;
+    i = 0;
+    iLeapDays = 0;
+
+    while (i <= iYearsElapsed)
+    {
+        if ((i % 100) == 20)
+        {
+            if ((i % 400) == 20)
+            {
+                iLeapDays++;
+            }
+        }
+        else if ((i % 4) == 0)
+        {
+            iLeapDays++;
+        }
+        i++;
+    }
+    if ((iYearsElapsed % 100) == 20)
+    {
+        if (((iYearsElapsed % 400) == 20) && (iMo <= 2))
+        {
+            iLeapDays--;
+        }
+    }
+    else if (((iYearsElapsed % 4) == 0) && (iMo <= 2))
+    {
+        iLeapDays--;
+    }
+    iDaysElapsed = iYearsElapsed*365 + (int)doy[iMo - 1] + iDay + iLeapDays - 6;
+
+    return (iDaysElapsed * 24 + iHr);
+}
+
+void
+send_assistance_data (int iYr, int iMo, int iDay, int iHr, char * timeInfo, int iTimeLen)
+{
+    TRC();
+    int fp, ret = 0;
+    int i, segment, epo_gps_hour, current_gps_hour;
+    unsigned epobuf[MTKEPO_RECORD_SIZE/sizeof(unsigned)];
+    char strbuf[200], outbuf[200];
+    GpsState*  s = _gps_state;
+    // open EPO file and read the header (assume EPO file has passed integrity check)
+    fp = open(MTK_GPS_DATA_PATH"EPOHAL.DAT", O_RDONLY);
+    if (fp < 0)
+    {
+        DBG("!!!!!!no EPO file ERROR: %d, %s", errno, strerror(errno));
+        return;
+    }
+    ret = read(fp, &epo_gps_hour, sizeof(int));
+    epo_gps_hour &= 0x00FFFFFF;
+
+    current_gps_hour = utc_to_gps_hour(iYr, iMo, iDay, iHr);
+    segment = (current_gps_hour - epo_gps_hour) / 6;
+    if ((segment < 0) || (segment >= MTKEPO_SEGMENT_NUM))
+    {
+        DBG("!!!!!segment ERROR : %d", segment);
+        return;
+    }
+    // read binary EPO data and sent it to MT3339
+    lseek(fp, segment*(MTKEPO_RECORD_SIZE)*(MTKEPO_SV_NUMBER), SEEK_SET);
+    DBG("ready to write time info before send EPO data");
+    ret = write(s->tty_fd, timeInfo, iTimeLen);
+    usleep(1000*200);
+    for (i = 0; i < MTKEPO_SV_NUMBER; i++)
+    {
+        read(fp, epobuf, MTKEPO_RECORD_SIZE);
+        // assume host system is little-endian
+        sprintf(strbuf,"PMTK721,%X,%X,%X,%X,%X,%X,%X,%X,%X,%X,%X,%X,%X,%X,%X,%X,%X,%X,%X",
+        i+1,
+        epobuf[0], epobuf[1], epobuf[2], epobuf[3], epobuf[4], epobuf[5],
+        epobuf[6], epobuf[7], epobuf[8], epobuf[9], epobuf[10], epobuf[11],
+        epobuf[12], epobuf[13], epobuf[14], epobuf[15], epobuf[16], epobuf[17]);
+        sprintf(outbuf, "$%s*%02X\r\n", strbuf, calc_nmea_checksum(strbuf));
+        // send them by UART
+        DBG("!!!!this EPO data len is %d,data is : %s", strlen(outbuf), outbuf); // for demo
+        for (int j = 0; j < 3; j++)
+        {
+            ret = write(s->tty_fd, outbuf, strlen(outbuf));
+            if (ret < 0)
+                DBG("Write EPO data fail, errno is %d", errno);
+            else
+                j = 3;
+        }
+        if (i%10 == 0)
+            usleep(1000*200);
+    }
+    close(fp);
+}
+
+/*for reducing the function call to get data from kernel*/
+static char buffGGA[2048];
+/*gps nmea read thread */
+static bool g_NmeaReadStart = false;
+static bool g_ThreadExistNmeaRead = false;
+static bool g_GpsDriverStart = false;
+static pthread_mutex_t g_mutx;
+
+void
+gps_read_nmea_from_uart_thread(void* arg)
+{
+    g_ThreadExistNmeaRead = true;
+    GpsState*   state = (GpsState*) arg;
+    int fd = state->tty_fd;
+    while (g_ThreadExistNmeaRead)
+    {
+        if(g_GpsDriverStart && g_NmeaReadStart)
+        {
+            int  nn, ret;
+            memset(buffGGA, 0, sizeof(buffGGA));
+            ret = read( fd, buffGGA, sizeof(buffGGA) );
+            gps_nmea_end_tag = 0;
+
+            DBG("before PARSE buffer[%d] is:%s.", ret, buffGGA);
+            memset(g_NmeaReader->in, 0, sizeof(g_NmeaReader->in));
+            for (nn = 0; nn < ret && g_GpsDriverStart; nn++)
+            {
+                if(nn == (ret-1))
+                    gps_nmea_end_tag = 1;
+
+                nmea_reader_addc( g_NmeaReader, buffGGA[nn] );
+            }
+            g_NmeaReadStart = false;
+        }
+        usleep(100);
+    }
+    DBG("gps_read_nmea_from_uart_thread exit!");
+}
+/* this is the main thread, it waits for commands from gps_state_start/stop and,
+ * when started, messages from the GPS daemon. these are simple NMEA sentences
+ * that must be parsed to be converted into GPS fixes sent to the framework
+ */
+void
+gps_state_thread( void*  arg )
+{
+    static float count = 0;
+    GpsState*   state = (GpsState*) arg;
+    state->test_time += 1;
+    int         tty_fd     = state->tty_fd;
+    int         control_fd = state->control[1];
+    int         pow_fd     = state->pow_fd;
+
+    int epoll_fd = state->epoll_hd;
+    int         test_started = 0;
+
+    nmea_reader_init( g_NmeaReader );
+
+    // register control file descriptors for polling
+    if(epoll_register( epoll_fd, control_fd ) < 0)
+        ERR("control_fd register control_fd error, error num is %d\n, message is %s\n", errno, strerror(errno));
+    if(epoll_register( epoll_fd, tty_fd) < 0)
+        ERR("tty_fd register control_fd error, error num is %d\n, message is %s\n", errno, strerror(errno));
+    //if(epoll_register( epoll_fd, pow_fd) < 0)
+    if(epoll_add_fd( epoll_fd, pow_fd) < 0)
+        ERR("pow_fd register control_fd error, error num is %d\n, message is %s\n", errno, strerror(errno));
+
+    release_condition(&lock_for_sync[M_INIT]);
+
+    // now loop
+    for (;;)
+    {
+        struct epoll_event   events[5];
+        int                  ne, nevents;
+        nevents = epoll_wait( epoll_fd, events, 5, -1 );
+        if (nevents < 0)
+        {
+            if (errno != EINTR)
+                ERR("epoll_wait() unexpected error: %s", strerror(errno));
+            continue;
+        }
+
+        for (ne = 0; ne < nevents; ne++)
+        {
+            if ((events[ne].events & (EPOLLERR|EPOLLHUP)) != 0)
+            {
+                ERR("EPOLLERR or EPOLLHUP after epoll_wait() !?");
+                goto Exit;
+            }
+            if ((events[ne].events & EPOLLIN) != 0)
+            {
+                int  fd = events[ne].data.fd;
+
+                if (fd == pow_fd)
+                {
+                    ERR("!!!!!!!!!!!EPO donwload done");
+                    char  cmd = 255;
+                    int   ret;
+
+                    //socket
+                    char epo_buff[100] = {0};
+                    int offset = 0;
+                    int read_len;
+
+                    read_len = safe_recvfrom(fd, epo_buff, sizeof(epo_buff));
+                    if (read_len <= 0) {
+                        DBG("@@@@@@@@@gpsinf3337() safe_recvfrom() failed read_len=%d", read_len);
+                        break;
+                    }
+                    cmd = get_int(epo_buff, &offset, sizeof(epo_buff));
+
+                    if (cmd == CMD_EPO_DOWNLOAD_DONE) {
+                        DBG("@@@@@@@@@@@@got the EPO download msg");
+                        callback_backup.create_thread_cb(gps_send_epo_thread, mtk_gps_send_EPO, NULL);
+                    }
+                }
+                else if (fd == control_fd)
+                {
+                    char  cmd = 255;
+                    int   ret;
+                    do {
+                        ret = read( fd, &cmd, 1 );
+                    } while (ret < 0 && errno == EINTR);
+
+                    if (cmd == CMD_QUIT) {
+                        DBG("gps thread quitting on demand");
+                        goto Exit;
+                    }
+                    else if (cmd == CMD_START) {
+                        if (!started) {
+                            started = 1;
+                            nmea_reader_set_callback( g_NmeaReader, &state->callbacks);
+                            switch (g_delete_aiding_data_flag) {
+                                case 1:
+                                    DBG("Last time's delete_aiding : hot start");
+                                    ret = write(tty_fd, "$PMTK101*32\r\n", 13);
+                                    g_EpoSend = true;
+                                    break;
+                                case 2:
+                                    DBG("Last time's delete_aiding : warm start");
+                                    ret = write(tty_fd, "$PMTK102*31\r\n", 13);
+                                    g_EpoSend = true;
+                                    break;
+                                case 3:
+                                    DBG("Last time's delete_aiding : cold start");
+                                    ret = write(tty_fd, "$PMTK103*30\r\n", 13);
+                                    g_EpoSend = true;
+                                    break;
+                                case 4:
+                                    DBG("Last time's delete_aiding : full start");
+                                    ret = write(tty_fd, "$PMTK104*37\r\n", 13);
+                                    g_EpoSend = true;
+                                    break;
+                                default:
+                                    break;
+                            }
+                            g_delete_aiding_data_flag = 0;
+                        }
+                    }
+                    else if (cmd == CMD_STOP) {
+                        if (started) {
+                            started = 0;
+                            nmea_reader_set_callback( g_NmeaReader, NULL );
+                            release_condition(&lock_for_sync[M_STOP]);
+                            DBG("CMD_STOP has been receiving from HAL thread, release lock so can handle CLEAN_UP\n");
+                        }
+                    }
+                    else if (cmd == CMD_RESTART) {
+                        g_NmeaReader->fix_mode = 0;
+                        DBG("gps 3337 restart!!!!");
+                    }
+                }
+                else if (fd == tty_fd)
+                {
+                    if(!flag_unlock)
+                    {
+                        release_condition(&lock_for_sync[M_START]);
+                        flag_unlock = 1;
+                        DBG("got first NMEA sentence, release lock to set state ENGINE ON, SESSION BEGIN");
+                    }
+                    if(report_time_interval > ++count){
+                        DBG("[trace]count is %f\n", count);
+                        //int ret = read( fd, buff, sizeof(buff) );
+                        continue;
+                    }
+                    count = 0;
+                    g_NmeaReadStart = true;
+                }
+            }
+        }
+    }
+Exit:
+    DBG("HAL thread is exiting, release lock to clean resources\n");
+    release_condition(&lock_for_sync[M_CLEANUP]);
+    return;
+}
+static void
+gps_state_done( GpsState*  s )
+{
+    TRC();
+    char   cmd = CMD_QUIT;
+
+    write( s->control[0], &cmd, 1 );
+    get_condition(&lock_for_sync[M_CLEANUP]);
+
+    g_ThreadExitPMTKIn = false;
+    g_hPowerGPS = INVALID_FD;
+    pthread_join(s->pmtk_thread->thread, NULL);
+    g_ThreadExistNmeaRead = false;
+    pthread_join(s->nmea_read_thread, NULL);
+
+    close( s->control[0] ); s->control[0] = -1;
+    close( s->control[1] ); s->control[1] = -1;
+    close( s->pow_fd ); s->pow_fd = -1;
+    close( s->tty_fd ); s->tty_fd = -1;
+    close(s->epoll_hd); s->epoll_hd = -1;
+    s->init = 0;
+    s->test_time -= 1;
+    DBG("GPS cleanup done");
+
+    return;
+}
+
+
+static void
+gps_state_start( GpsState*  s )
+{
+    char  cmd = CMD_START;
+    int   ret;
+
+    do { ret=write( s->control[0], &cmd, 1 ); }
+    while (ret < 0 && errno == EINTR);
+
+    if (ret != 1)
+        ERR("%s: could not send CMD_START command: ret=%d: %s",
+          __FUNCTION__, ret, strerror(errno));
+}
+
+static void
+gps_state_stop( GpsState*  s )
+{
+    char  cmd = CMD_STOP;
+    int   ret;
+
+    do { ret=write( s->control[0], &cmd, 1 ); }
+    while (ret < 0 && errno == EINTR);
+
+    if (ret != 1)
+        ERR("%s: could not send CMD_STOP command: ret=%d: %s",
+          __FUNCTION__, ret, strerror(errno));
+}
+
+static void
+gps_state_restart( GpsState*  s )
+{
+    char  cmd = CMD_RESTART;
+    int   ret;
+
+    do { ret=write( s->control[0], &cmd, 1 ); }
+    while (ret < 0 && errno == EINTR);
+
+    if (ret != 1)
+        ERR("%s: could not send CMD_RESTART command: ret=%d: %s",
+          __FUNCTION__, ret, strerror(errno));
+}
+
+
+static void
+gps_state_init( GpsState*  state )
+{
+    state->control[0] = -1;
+    state->control[1] = -1;
+    state->pow_fd     = -1;
+    state->tty_fd     = -1;
+
+    TRC();
+
+    //socket
+    state->pow_fd = socket_bind_udp(MNLD_HAL2GPS);
+    socket_set_blocking(state->pow_fd, 0);
+    if (state->pow_fd < 0) {
+        ERR("no gps hardware detected: %s:%d, %s", MNLD_HAL2GPS, state->pow_fd, strerror(errno));
+        return;
+    }
+
+    state->tty_fd = open(GPS_TTY_NAME, O_RDWR | O_NOCTTY | O_NONBLOCK);
+    if (state->tty_fd < 0) {
+        close(state->pow_fd);
+        state->pow_fd = -1;
+        ERR("no gps hardware detected: %s:%d, %s", GPS_TTY_NAME, state->tty_fd, strerror(errno));
+        return;
+    }
+    struct termios options;
+    int i4_baud = B115200;
+    tcgetattr(state->tty_fd, &options);
+    cfsetispeed(&options, i4_baud);
+    cfsetospeed(&options, i4_baud);
+
+    options.c_cflag |= (CLOCAL | CREAD);
+    options.c_cflag &= ~PARENB;
+    options.c_cflag &= ~CSTOPB;
+    options.c_cflag &= ~CSIZE;
+    options.c_cflag &= ~PARODD;
+    options.c_cflag |= CS8;
+    options.c_cflag &= ~CRTSCTS;
+    options.c_lflag &= ~(ISIG | ECHO);
+    options.c_oflag &= ~OPOST;
+    options.c_iflag &= ~(INLCR | INPCK | ISTRIP | IXON | BRKINT );
+    options.c_cc[VMIN] = 1;
+    options.c_cc[VTIME] = 0;
+    tcsetattr(state->tty_fd, TCSANOW, &options);
+
+    int epoll_fd = epoll_create(3);
+    state->epoll_hd = epoll_fd;
+
+    if ( socketpair( AF_LOCAL, SOCK_STREAM, 0, state->control ) < 0 ) {
+        ERR("could not create thread control socket pair: %s", strerror(errno));
+        goto Fail;
+    }
+    state->thread = callback_backup.create_thread_cb(gps_native_thread, gps_state_thread, state);
+    if (!state->thread){
+        ERR("could not create gps thread: %s", strerror(errno));
+        goto Fail;
+    }
+
+    DBG("gps state initialized, the thread is %d\n", (int)state->thread);
+    if (!g_ThreadExitPMTKIn)
+    {
+    state->pmtk_thread->thread= callback_backup.create_thread_cb(gps_pmtk_thread, powergps_pmtk_receive_thread, state);
+    if (!state->pmtk_thread->thread){
+        ERR("could not create gps pmtk thread: %s", strerror(errno));
+        goto Fail;
+        }
+    }
+
+    if (!g_ThreadExistNmeaRead)
+    {
+        state->nmea_read_thread = callback_backup.create_thread_cb(gps_nmea_read_thread, gps_read_nmea_from_uart_thread, state);
+        if (!state->nmea_read_thread){
+            ERR("could not create nmea read thread: %s", strerror(errno));
+            goto Fail;
+        }
+    }
+
+    DBG("gps PMTK initialized, the thread is %d\n", (int)state->pmtk_thread->thread);
+
+    return;
+
+Fail:
+    gps_state_done( state );
+}
+
+
+/*****************************************************************/
+/*****************************************************************/
+/*****                                                       *****/
+/*****       I N T E R F A C E                               *****/
+/*****                                                       *****/
+/*****************************************************************/
+/*****************************************************************/
+static int
+mtk_gps_mt3337_init(GpsCallbacks* callbacks)
+{
+    TRC();
+    GpsState*  s = _gps_state;
+    int get_time = 20;
+    int res = 0;
+    if(s->init)
+        return 0;
+    s->callbacks = *callbacks;
+    callback_backup = *callbacks;
+
+    gps_state_init(s);
+    get_condition(&lock_for_sync[M_INIT]);
+    usleep(1000*1);
+    s->init = 1;
+    DBG("Set GPS_CAPABILITY_SCHEDULING \n");
+    callback_backup.set_capabilities_cb(GPS_CAPABILITY_SCHEDULING);
+
+    if (gpshal_gpscbs_save(callbacks) != 0) {
+        return -1;    //  error
+    }
+
+    gpshal_set_gps_state_intent(GPSHAL_STATE_INIT);
+    gpshal2mnl_gps_init();
+    return 0;
+}
+
+static void
+mtk_gps_mt3337_cleanup(void)
+{
+    GpsState*  s = _gps_state;
+
+    TRC();
+
+    if(s->start_flag)
+    get_condition(&lock_for_sync[M_STOP]); //make sure gps_stop has set state to GPS_STATUS_ENGINE_OFF by callback function
+    if(lock_for_sync[M_STOP].condtion == 1)
+    {
+        lock_for_sync[M_STOP].condtion = 0; //make sure gps_stop has set state to GPS_STATUS_ENGINE_OFF in next time
+    }
+    if (s->init)
+        gps_state_done(s);
+    gpshal_set_gps_state_intent(GPSHAL_STATE_CLEANUP);
+    gpshal2mnl_gps_cleanup();
+    DBG("mtk_gps_cleanup done");
+}
+
+int
+mtk_gps_mt3337_start()
+{
+    TRC();
+    GpsState*  s = _gps_state;
+    int err;
+    int count=0;
+
+
+    if (!s->init) {
+        ERR("%s: called with uninitialized state !!", __FUNCTION__);
+        return -1;
+    }
+
+    while(s->start_flag == 1)
+    {
+        usleep(100000);
+        count++;
+        DBG("mtk_gps_start:start_flag = %d delay=%d \n",s->start_flag,count*100);
+    }
+    mtk_gps_start_driver();
+    g_GpsDriverStart = true;
+    DBG("mtk_gps_mt3337_start done!!!!");
+    mnl_load_property();
+
+    get_condition(&lock_for_sync[M_START]);
+    gps_state_start(s);
+
+    sta.status = GPS_STATUS_ENGINE_ON;
+    callback_backup.status_cb(&sta);
+    sta.status = GPS_STATUS_SESSION_BEGIN;
+    callback_backup.status_cb(&sta);
+
+    callback_backup.acquire_wakelock_cb();//avoid cpu to sleep
+    s->start_flag = 1;
+
+    gpshal_set_gps_state_intent(GPSHAL_STATE_START);
+    gpshal2mnl_gps_start();
+    return 0;
+}
+
+int
+mtk_gps_mt3337_stop()
+{
+    TRC();
+    GpsState*  s = _gps_state;
+    int err;
+    int count=0;
+
+    if (!s->init) {
+        ERR("%s: called with uninitialized state !!", __FUNCTION__);
+        return -1;
+    }
+
+    while(s->start_flag == 0)
+    {
+        usleep(100000);
+        count++;
+        DBG("mtk_gps_stop:start_flag = %d delay=%d \n",s->start_flag,count*100);
+    }
+    s->start_flag = 0;
+
+    mtk_gps_stop_driver();
+    g_GpsDriverStart = false;
+    flag_unlock = 0;
+    gps_state_stop(s);
+    gpshal_set_gps_state_intent(GPSHAL_STATE_STOP);
+    gpshal2mnl_gps_stop();
+
+    callback_backup.release_wakelock_cb();
+    DBG("mtk_gps_mt3337_STOP done!!!!");
+    return 0;
+}
+
+static int
+mtk_gps_mt3337_inject_time(GpsUtcTime time, int64_t timeReference, int uncertainty)
+{
+    ntp_context inject_ntp;
+    long long time_s = 0;
+    int offset = 0;
+
+    TRC();
+    time_s = time/1000;
+    DBG("inject time= %lld,ctime = %s, timeReference = %lld,uncertainty =%d\n", time,ctime(&time_s), timeReference,uncertainty);
+    memcpy(&(inject_ntp.time),&time,sizeof(GpsUtcTime));
+    inject_ntp.timeReference = timeReference;
+    inject_ntp.uncertainty = uncertainty;
+
+    //do not support detail function
+    return 0;
+}
+
+static int
+mtk_gps_mt3337_inject_location(double latitude, double longitude, float accuracy)
+{
+    nlp_context nlp_location;
+    int offset = 0;
+
+    if(clock_gettime(CLOCK_MONOTONIC , &nlp_location.ts) == -1)
+    {
+        ERR("clock_gettime failed reason=[%s]\n",strerror(errno));
+        return -1;
+    }
+    DBG("ts.tv_sec= %lld,ts.tv_nsec = %lld\n", nlp_location.ts.tv_sec,nlp_location.ts.tv_nsec);
+    DBG("inject location lati= %f, longi = %f,accuracy =%f\n", latitude, longitude,accuracy);
+
+    //do not support detail function
+    return 0;
+}
+
+static void
+mtk_gps_mt3337_delete_aiding_data(GpsAidingData flags)
+{
+    /*workaround to trigger hot/warm/cold/full start*/
+    #define FLAG_HOT_START  GPS_DELETE_RTI
+    #define FLAG_WARM_START GPS_DELETE_EPHEMERIS
+    #define FLAG_COLD_START (GPS_DELETE_EPHEMERIS | GPS_DELETE_POSITION | GPS_DELETE_TIME | GPS_DELETE_IONO | GPS_DELETE_UTC | GPS_DELETE_HEALTH)
+    #define FLAG_FULL_START (GPS_DELETE_ALL)
+    #define FLAG_AGPS_START (GPS_DELETE_EPHEMERIS | GPS_DELETE_ALMANAC | GPS_DELETE_POSITION | GPS_DELETE_TIME | GPS_DELETE_IONO | GPS_DELETE_UTC)
+    GpsState*  s = _gps_state;
+    int ret;
+
+    DBG("%s:0x%X\n", __FUNCTION__, flags);
+
+    gps_state_restart(s);
+
+    if (flags == FLAG_HOT_START)
+    {
+        mtk_restart(MNL_CMD_RESTART_HOT);
+        if (g_GpsDriverStart)
+        {
+            DBG("GPS driver still start!!! send it HOT_START!!!");
+            ret = write(s->tty_fd, "$PMTK101*32\r\n", 13);
+            if (ret < 0)
+                DBG("HOT_START FAILED!!! error is %d : %s", errno, strerror(errno));
+            g_EpoSend = true;
+        }
+        else
+        {
+            g_delete_aiding_data_flag = 1;
+        }
+    }
+    else if (flags == FLAG_WARM_START)
+    {
+        mtk_restart(MNL_CMD_RESTART_WARM);
+        if (g_GpsDriverStart)
+        {
+            DBG("GPS driver still start!!! send it WARM_START!!!");
+            ret = write(s->tty_fd, "$PMTK102*31\r\n", 13);
+            if (ret < 0)
+                DBG("WARM_START FAILED!!! error is %d : %s", errno, strerror(errno));
+            g_EpoSend = true;
+        }
+        else
+        {
+            g_delete_aiding_data_flag = 2;
+        }
+    }
+    else if (flags == FLAG_COLD_START)
+    {
+        mtk_restart(MNL_CMD_RESTART_HOT);
+        if (g_GpsDriverStart)
+        {
+            DBG("GPS driver still start!!! send it COLD_START!!!");
+            ret = write(s->tty_fd, "$PMTK103*30\r\n", 13);
+            if (ret < 0)
+                DBG("COLD_START FAILED!!! error is %d : %s", errno, strerror(errno));
+            g_EpoSend = true;
+        }
+        else
+        {
+            g_delete_aiding_data_flag = 3;
+        }
+    }
+    else if (flags == FLAG_FULL_START)
+    {
+        mtk_restart(MNL_CMD_RESTART_HOT);
+        if (g_GpsDriverStart)
+        {
+            DBG("GPS driver still start!!! send it COLD_START!!!");
+            ret = write(s->tty_fd, "$PMTK104*37\r\n", 13);
+            if (ret < 0)
+                DBG("FULL_START FAILED!!! error is %d : %s", errno, strerror(errno));
+            g_EpoSend = true;
+        }
+        else
+        {
+            g_delete_aiding_data_flag = 4;
+        }
+    }
+    else if(flags == FLAG_AGPS_START)
+    {
+        DBG("Send MNL_CMD_RESTART_AGPS in HAL\n");
+        mtk_restart(MNL_CMD_RESTART_AGPS);
+    }
+}
+
+static int mtk_gps_mt3337_set_position_mode(GpsPositionMode mode, GpsPositionRecurrence recurrence,
+            uint32_t min_interval, uint32_t preferred_accuracy, uint32_t preferred_time)
+{
+    // FIXME - support fix_frequency
+    // only standalone supported for now.
+    DBG("set report location time interval is %d\n", min_interval);
+    if(min_interval <= 1000)
+        report_time_interval = 1;
+    else
+        report_time_interval = (float)min_interval/1000;
+    DBG("set report location time interval is %f s\n", report_time_interval);
+    TRC();
+    return 0;
+}
+
+static const void*
+mtk_gps_mt3337_get_extension(const char* name)
+{
+    TRC();
+    DBG("mtk_gps_get_extension name=[%s]\n", name);
+    if (strcmp(name, AGPS_RIL_INTERFACE) == 0) {
+        return &mtk_agps_ril_inf;
+    }
+/*
+#if EPO_SUPPORT
+    if (!strcmp(name, GPS_XTRA_INTERFACE))
+        return (void*)(&mtkGpsXtraInterface);
+#endif
+*/
+    return NULL;
+}
+
+static const GpsInterface  mtkGpsInterface = {
+    sizeof(GpsInterface),
+    mtk_gps_mt3337_init,
+    mtk_gps_mt3337_start,
+    mtk_gps_mt3337_stop,
+    mtk_gps_mt3337_cleanup,
+    mtk_gps_mt3337_inject_time,
+    mtk_gps_mt3337_inject_location,
+    mtk_gps_mt3337_delete_aiding_data,
+    mtk_gps_mt3337_set_position_mode,
+    mtk_gps_mt3337_get_extension,
+};
+
+//=========================================================
+// Between
+//     Gps Interface
+//     Hardware Module Interface
+
+static const GpsInterface* gps_device__get_gps_interface(
+        __unused struct gps_device_t* device) {
+    /*
+     * hao mt3337 modify
+     * GPS_DEVICE__GET_GPS_INTERFACE__CHECK_PARAM;
+     * hal2mnl_hal_reboot();
+     */
+    return &mtkGpsInterface;
+}
+
+static const struct gps_device_t gps_device = {
+    .common = {                           // hw_device_t
+        .tag     = HARDWARE_DEVICE_TAG,
+        .version = 0,                     // GPS JNI will not use it
+        .module  = &HAL_MODULE_INFO_SYM,
+        .reserved = {0},
+        .close   = NULL                   // GPS JNI will not call it
+        },
+    .get_gps_interface = gps_device__get_gps_interface
+};
+
+
+static int open_gps(const struct hw_module_t* module, char const* name,
+        struct hw_device_t** device)
+{
+    DBG("open_gps HAL 1\n");
+    *device = (struct hw_device_t*)&gps_device;
+    return 0;
+}
+
+
+static struct hw_module_methods_t gps_module_methods = {
+    .open = open_gps
+};
+
+
+struct hw_module_t HAL_MODULE_INFO_SYM = {
+    .tag = HARDWARE_MODULE_TAG,
+    .version_major = 1,
+    .version_minor = 0,
+    .id  = GPS_HARDWARE_MODULE_ID,
+    .name   = "MediaTek GPS Hardware Module",
+    .author = "MediaTek, Inc.",
+    .methods = &gps_module_methods,
+    .dso     = NULL,
+    .reserved = {0}
+};
diff --git a/src/connectivity/gps/gps_hal/src/hal2mnl_interface.c b/src/connectivity/gps/gps_hal/src/hal2mnl_interface.c
new file mode 100644
index 0000000..4d6945b
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/src/hal2mnl_interface.c
@@ -0,0 +1,623 @@
+#include "hal2mnl_interface.h"
+#include "mtk_lbs_utility.h"
+#include "data_coder.h"
+#include "mtk_auto_log.h"
+
+int log_dbg_level = L_DEBUG;
+
+#ifdef LOG_TAG
+#undef LOG_TAG
+#define LOG_TAG "hal2mnl"
+#endif
+
+#ifndef MIN
+#define MIN(A,B) ((A)<(B)?(A):(B))
+#endif
+
+static float count = 0;
+static float report_time_interval = 0;
+
+int hal2mnl_hal_reboot() {
+    LOGI("hal2mnl_hal_reboot");
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+    put_int(buff, &offset, HAL2MNL_HAL_REBOOT);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_gps_init() {
+    LOGI("hal2mnl_gps_init");
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_GPS_INIT);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_gps_start() {
+    LOGI("hal2mnl_gps_start");
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_GPS_START);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+int hal2mnl_gps_stop() {
+    LOGI("hal2mnl_gps_stop");
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_GPS_STOP);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_gps_cleanup() {
+    LOGI("hal2mnl_gps_cleanup");
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_GPS_CLEANUP);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_gps_inject_time(int64_t time, int64_t time_reference, int uncertainty) {
+    /*LOGD("hal2mnl_gps_inject_time  time=%zd time_reference=%zd uncertainty=%d",
+        time, time_reference, uncertainty);*/
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_GPS_INJECT_TIME);
+    put_long(buff, &offset, time);
+    put_long(buff, &offset, time_reference);
+    put_int(buff, &offset, uncertainty);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_gps_inject_location(double lat, double lng, float acc) {
+    // LOGD("hal2mnl_gps_inject_location  lat,lng %f,%f acc=%f", lat, lng, acc);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_GPS_INJECT_LOCATION);
+    put_double(buff, &offset, lat);
+    put_double(buff, &offset, lng);
+    put_float(buff, &offset, acc);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_gps_delete_aiding_data(int flags) {
+    LOGD("flag=0x%x", flags);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_GPS_DELETE_AIDING_DATA);
+    put_int(buff, &offset, flags);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_gps_set_position_mode(gps_pos_mode mode, gps_pos_recurrence recurrence,
+    int min_interval, int preferred_acc, int preferred_time, bool lowPowerMode) {
+    LOGD("mode=%d recurrence=%d min_interval=%d preferred_acc=%d preferred_time=%d lowpowermode=%d",
+        mode, recurrence, min_interval, preferred_acc, preferred_time, lowPowerMode);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_GPS_SET_POSITION_MODE);
+    put_int(buff, &offset, mode);
+    put_int(buff, &offset, recurrence);
+    put_int(buff, &offset, min_interval);
+    put_int(buff, &offset, preferred_acc);
+    put_int(buff, &offset, preferred_time);
+    put_byte(buff, &offset, lowPowerMode);
+
+    if (min_interval <= 1000) {
+        report_time_interval = 1;
+    } else {
+        report_time_interval = (float)min_interval/1000;
+    }
+    LOGD("set report location time interval is %f s\n", report_time_interval);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_data_conn_open(const char* apn) {
+    LOGD("apn=[%s]", apn);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_DATA_CONN_OPEN);
+    put_string(buff, &offset, apn);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_data_conn_open_with_apn_ip_type(const char* apn, apn_ip_type ip_type) {
+    LOGD("apn=[%s] ip_type=%d",
+        apn, ip_type);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_DATA_CONN_OPEN_WITH_APN_IP_TYPE);
+    put_string(buff, &offset, apn);
+    put_int(buff, &offset, ip_type);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_data_conn_closed() {
+    LOGD("hal2mnl_data_conn_closed");
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_DATA_CONN_CLOSED);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_data_conn_failed() {
+    LOGD("hal2mnl_data_conn_failed");
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_DATA_CONN_FAILED);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_set_server(agps_type type, const char* hostname, int port) {
+    LOGD("type=%d hostname=[%s] port=%d",
+        type, hostname, port);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_SET_SERVER);
+    put_int(buff, &offset, type);
+    put_string(buff, &offset, hostname);
+    put_int(buff, &offset, port);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+    return 0;
+}
+
+int hal2mnl_set_ref_location(cell_type type, int mcc, int mnc, int lac, int cid) {
+    LOGD("ype=%d mcc=%d mnc=%d lac=%d cid=%d",
+        type, mcc, mnc, lac, cid);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_SET_REF_LOCATION);
+    put_int(buff, &offset, type);
+    put_int(buff, &offset, mcc);
+    put_int(buff, &offset, mnc);
+    put_int(buff, &offset, lac);
+    put_int(buff, &offset, cid);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_set_id(agps_id_type type, const char* setid) {
+    LOGD("type=%d setid=[%s]", type, setid);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_SET_ID);
+    put_int(buff, &offset, type);
+    put_string(buff, &offset, setid);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+
+int hal2mnl_ni_message(char* msg, int len) {
+    LOGD("len=%d", len);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_NI_MESSAGE);
+    put_binary(buff, &offset, msg, len);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+#if defined(__LINUX_OS__)
+int hal2mnl_send_pmtk(char* msg, int len) {
+    LOGD("len=%d", len);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_SEND_PMTK);
+    put_binary(buff, &offset, msg, len);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+#endif
+
+int hal2mnl_ni_respond(int notif_id, ni_user_response_type user_response) {
+    LOGD("notif_id=%d user_response=%d",
+        notif_id, user_response);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_NI_RESPOND);
+    put_int(buff, &offset, notif_id);
+    put_int(buff, &offset, user_response);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_update_network_state(int connected, network_type type, int roaming,
+    const char* extra_info) {
+    LOGD("connected=%d type=%d roaming=%d extra_info=[%s]",
+        connected, type, roaming, extra_info);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_UPDATE_NETWORK_STATE);
+    put_int(buff, &offset, connected);
+    put_int(buff, &offset, type);
+    put_int(buff, &offset, roaming);
+    put_string(buff, &offset, extra_info);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_update_network_availability(int available, const char* apn) {
+    LOGD("available=%d apn=[%s]",
+        available, apn);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_UPDATE_NETWORK_AVAILABILITY);
+    put_int(buff, &offset, available);
+    put_string(buff, &offset, apn);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_set_gps_measurement(bool enabled, bool enableFullTracking) {
+    LOGD("enabled=%d, flag=%d", enabled, enableFullTracking);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_GPS_MEASUREMENT);
+    put_int(buff, &offset, enabled);
+    put_int(buff, &offset, enableFullTracking);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_set_gps_navigation(bool enabled) {
+    LOGD("enabled=%d", enabled);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_GPS_NAVIGATION);
+    put_int(buff, &offset, enabled);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_set_vzw_debug(bool enabled) {
+    LOGD("enabled = %d\n", enabled);
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_VZW_DEBUG);
+    put_int(buff, &offset, enabled);
+
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+int hal2mnl_update_gnss_config(const char* config_data, int length) {
+    LOGD("data length:%d\n", length);
+    int offset = 0;
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    put_int(buff, &offset, HAL_MNL_INTERFACE_VERSION);
+
+    put_int(buff, &offset, HAL2MNL_GNSS_CONFIG);
+    put_int(buff, &offset, length);
+    put_string(buff, &offset, config_data);
+    return safe_sendto(MTK_HAL2MNL, buff, offset);
+}
+
+// -1 means failure
+int mnl2hal_hdlr(int fd, mnl2hal_interface* hdlr) {
+    char buff[HAL_MNL_BUFF_SIZE] = {0};
+    int offset = 0;
+    int ver;
+    mnl2hal_cmd cmd;
+    int read_len;
+    int ret = 0;
+
+    read_len = safe_recvfrom(fd, buff, sizeof(buff));
+    if (read_len <= 0) {
+        LOGE("mnl2hal_hdlr() safe_recvfrom() failed read_len=%d", read_len);
+        return -1;
+    }
+    ver = get_int(buff, &offset, sizeof(buff));
+    UNUSED(ver);
+    cmd = get_int(buff, &offset, sizeof(buff));
+
+    switch (cmd) {
+    case MNL2HAL_MNLD_REBOOT: {
+        if (hdlr->mnld_reboot) {
+            hdlr->mnld_reboot();
+        } else {
+            LOGE("mnl2hal_hdlr() mnld_reboot is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_LOCATION: {
+        if (report_time_interval > ++count) {
+            LOGD("count is %f, interval is %f\n", count, report_time_interval);
+            break;
+        }
+        count = 0;
+
+        if (hdlr->location) {
+            gps_location location;
+            get_binary(buff, &offset, (char*)&location, sizeof(buff), sizeof(gps_location));
+            hdlr->location(location);
+        } else {
+            LOGE("mnl2hal_hdlr() location is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_GPS_STATUS: {
+        if (hdlr->gps_status) {
+            gps_status status;
+            get_binary(buff, &offset, (char*)&status, sizeof(buff), sizeof(gps_status));
+            hdlr->gps_status(status);
+        } else {
+            LOGE("mnl2hal_hdlr() gps_status is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_GPS_SV: {
+        if (hdlr->gps_sv) {
+            gnss_sv_info sv;
+            get_binary(buff, &offset, (char*)&sv, sizeof(buff), sizeof(gnss_sv_info));
+            hdlr->gps_sv(sv);
+        } else {
+            LOGE("mnl2hal_hdlr() gps_sv is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_NMEA: {
+        if (hdlr->nmea) {
+            int64_t timestamp = get_long(buff, &offset, sizeof(buff));
+            char* nmea = get_string(buff, &offset, sizeof(buff));
+            int used_length = nmea - buff;
+            int max_length = sizeof(buff) - used_length;
+            int length = get_int(buff, &offset, sizeof(buff));
+            length = MIN(length,max_length);
+            hdlr->nmea(timestamp, nmea, length);
+        } else {
+            LOGE("mnl2hal_hdlr() nmea is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_GPS_CAPABILITIES: {
+        if (hdlr->gps_capabilities) {
+            gps_capabilites capabilities;
+            get_binary(buff, &offset, (char*)&capabilities, sizeof(buff), sizeof(gps_capabilites));
+            hdlr->gps_capabilities(capabilities);
+        } else {
+            LOGE("mnl2hal_hdlr() gps_capabilities is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_GPS_MEASUREMENTS: {
+        if (hdlr->gps_measurements) {
+            gps_data data;
+            get_binary(buff, &offset, (char*)&data, sizeof(buff), sizeof(gps_data));
+            hdlr->gps_measurements(data);
+        } else {
+            LOGE("mnl2hal_hdlr() gps_measurements is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_GPS_NAVIGATION: {
+        if (hdlr->gps_navigation) {
+            gps_nav_msg msg;
+            get_binary(buff, &offset, (char*)&msg, sizeof(buff), sizeof(gps_nav_msg));
+            hdlr->gps_navigation(msg);
+        } else {
+            LOGE("mnl2hal_hdlr() gps_navigation is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_GNSS_MEASUREMENTS: {
+        if (hdlr->gnss_measurements) {
+            gnss_data data;
+            get_binary(buff, &offset, (char*)&data, sizeof(buff), sizeof(gnss_data));
+            hdlr->gnss_measurements(data);
+        } else {
+            LOGE("mnl2hal_hdlr() gnss_measurements is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_GNSS_NAVIGATION: {
+        if (hdlr->gnss_navigation) {
+            gnss_nav_msg msg;
+            get_binary(buff, &offset, (char*)&msg, sizeof(buff), sizeof(gnss_nav_msg));
+            hdlr->gnss_navigation(msg);
+        } else {
+            LOGE("mnl2hal_hdlr() gnss_navigation is NULL");
+            ret = -1;
+        }
+        break;
+    }
+
+    case MNL2HAL_REQUEST_WAKELOCK: {
+        if (hdlr->request_wakelock) {
+            hdlr->request_wakelock();
+        } else {
+            LOGE("mnl2hal_hdlr() request_wakelock is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_RELEASE_WAKELOCK: {
+        if (hdlr->release_wakelock) {
+            hdlr->release_wakelock();
+        } else {
+            LOGE("mnl2hal_hdlr() release_wakelock is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_REQUEST_UTC_TIME: {
+        if (hdlr->request_utc_time) {
+            hdlr->request_utc_time();
+        } else {
+            LOGE("mnl2hal_hdlr() request_utc_time is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_REQUEST_DATA_CONN: {
+        if (hdlr->request_data_conn) {
+            struct sockaddr_storage addr;
+            get_binary(buff, &offset, (char*)&addr, sizeof(buff), sizeof(addr));
+            hdlr->request_data_conn(&addr);
+        } else {
+            LOGE("mnl2hal_hdlr() request_data_conn is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_RELEASE_DATA_CONN: {
+        if (hdlr->release_data_conn) {
+            hdlr->release_data_conn();
+        } else {
+            LOGE("mnl2hal_hdlr() release_data_conn is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_REQUEST_NI_NOTIFY: {
+        if (hdlr->request_ni_notify) {
+            int session_id = get_int(buff, &offset, sizeof(buff));
+            agps_notify_type type = get_int(buff, &offset, sizeof(buff));
+            char* requestor_id = get_string(buff, &offset, sizeof(buff));
+            char* client_name = get_string(buff, &offset, sizeof(buff));
+            ni_encoding_type requestor_id_encoding = get_int(buff, &offset, sizeof(buff));
+            ni_encoding_type client_name_encoding  = get_int(buff, &offset, sizeof(buff));
+            hdlr->request_ni_notify(session_id, type, requestor_id, client_name,
+                requestor_id_encoding, client_name_encoding);
+        } else {
+            LOGE("mnl2hal_hdlr() request_ni_notify is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_REQUEST_SET_ID: {
+        if (hdlr->request_set_id) {
+            request_setid flags = get_int(buff, &offset, sizeof(buff));
+            hdlr->request_set_id(flags);
+        } else {
+            LOGE("mnl2hal_hdlr() request_set_id is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_REQUEST_REF_LOC: {
+        if (hdlr->request_ref_loc) {
+            request_refloc flags = get_int(buff, &offset, sizeof(buff));
+            hdlr->request_ref_loc(flags);
+        } else {
+            LOGE("mnl2hal_hdlr() request_ref_loc is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_VZW_DEBUG_OUTPUT: {
+        if (hdlr->output_vzw_debug) {
+            char* str = get_string(buff, &offset, sizeof(buff));
+            hdlr->output_vzw_debug(str);
+        } else {
+            LOGE("mnl2hal_hdlr() output_vzw_debug is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_UPDATE_GNSS_NAME: {
+        if (hdlr->update_gnss_name) {
+            int length = get_int(buff, &offset, sizeof(buff));
+            char* name = get_string(buff, &offset, sizeof(buff));
+            hdlr->update_gnss_name(name, length);
+        } else {
+            LOGE("mnl2hal_hdlr() update_gnss_name is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    case MNL2HAL_REQUEST_NLP: {
+        if (hdlr->request_nlp) {
+            bool independentFromGnss = get_byte(buff, &offset, sizeof(buff));
+            hdlr->request_nlp(independentFromGnss);
+        } else {
+            LOGE("mnl2hal_hdlr() update_gnss_name is NULL");
+            ret = -1;
+        }
+        break;
+    }
+    default: {
+        LOGE("mnl2hal_hdlr() unknown cmd=%d", cmd);
+        ret = -1;
+        break;
+    }
+    }
+
+    return ret;
+}
+
+// -1 means failure
+int create_mnl2hal_fd() {
+    int fd = socket_bind_udp(MTK_MNL2HAL);
+    socket_set_blocking(fd, 0);
+    return fd;
+}
+
diff --git a/src/connectivity/gps/gps_hal/src/hal_mnl_interface_common.c b/src/connectivity/gps/gps_hal/src/hal_mnl_interface_common.c
new file mode 100644
index 0000000..5a691a1
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/src/hal_mnl_interface_common.c
@@ -0,0 +1,173 @@
+#include <inttypes.h>
+
+#include "hal_mnl_interface_common.h"
+#include "mtk_lbs_utility.h"
+#include "mtk_auto_log.h"
+
+#ifdef LOG_TAG
+#undef LOG_TAG
+#define LOG_TAG "gpshal_dump"
+#endif
+
+#if 0
+void dump_gps_location(gps_location in) {
+    LOGD("===== dump_gps_location ====");
+    LOGD("flags=0x%x", in.flags);
+    LOGD("lat=%f", in.lat);
+    LOGD("lng=%f", in.lng);
+    LOGD("alt=%f", in.alt);
+    LOGD("speed=%f", in.speed);
+    LOGD("bearing=%f", in.bearing);
+    LOGD("accuracy=%f", in.accuracy);
+    LOGD("timestamp=%"PRId64, in.timestamp);
+}
+
+void dump_gnss_sv(gnss_sv in) {
+    LOGD("===== dump_gnss_sv ====");
+    LOGD("prn=%d", in.svid);
+    LOGD("constellation=%d", in.constellation);
+    LOGD("snr=%f", in.c_n0_dbhz);
+    LOGD("elevation=%f", in.elevation);
+    LOGD("azimuth=%f", in.azimuth);
+    LOGD("flags=%d", in.flags);
+}
+
+void dump_gnss_sv_info(gnss_sv_info in) {
+    int i = 0;
+    LOGD("===== dump_gnss_sv_info ====");
+    LOGD("num_svs=%d", in.num_svs);
+    for (i = 0; i < in.num_svs; i++) {
+        LOGD("i=%d", i);
+        dump_gnss_sv(in.sv_list[i]);
+    }
+}
+
+void dump_gps_measurement(gps_measurement in) {
+    LOGD("===== dump_gps_measurement ====");
+    LOGD("flags=0x%x", in.flags);
+    LOGD("prn=%d", in.prn);
+    LOGD("time_offset_ns=%f", in.time_offset_ns);
+    LOGD("state=0x%x", in.state);
+    LOGD("received_gps_tow_ns=%"PRId64, in.received_gps_tow_ns);
+    LOGD("received_gps_tow_uncertainty_ns=%"PRId64, in.received_gps_tow_uncertainty_ns);
+    LOGD("c_n0_dbhz=%f", in.c_n0_dbhz);
+    LOGD("pseudorange_rate_mps=%f", in.pseudorange_rate_mps);
+    LOGD("pseudorange_rate_uncertainty_mps=%f", in.pseudorange_rate_uncertainty_mps);
+    LOGD("accumulated_delta_range_state=0x%x", in.accumulated_delta_range_state);
+    LOGD("accumulated_delta_range_m=%f", in.accumulated_delta_range_m);
+    LOGD("accumulated_delta_range_uncertainty_m=%f", in.accumulated_delta_range_uncertainty_m);
+    LOGD("pseudorange_m=%f", in.pseudorange_m);
+    LOGD("pseudorange_uncertainty_m=%f", in.pseudorange_uncertainty_m);
+    LOGD("code_phase_chips=%f", in.code_phase_chips);
+    LOGD("code_phase_uncertainty_chips=%f", in.code_phase_uncertainty_chips);
+    LOGD("carrier_frequency_hz=%f", in.carrier_frequency_hz);
+    LOGD("carrier_cycles=%"PRId64, in.carrier_cycles);
+    LOGD("carrier_phase=%f", in.carrier_phase);
+    LOGD("carrier_phase_uncertainty=%f", in.carrier_phase_uncertainty);
+    LOGD("loss_of_lock=%d", in.loss_of_lock);
+    LOGD("bit_number=%d", in.bit_number);
+    LOGD("time_from_last_bit_ms=%d", in.time_from_last_bit_ms);
+    LOGD("doppler_shift_hz=%f", in.doppler_shift_hz);
+    LOGD("doppler_shift_uncertainty_hz=%f", in.doppler_shift_uncertainty_hz);
+    LOGD("multipath_indicator=%d", in.multipath_indicator);
+    LOGD("snr_db=%f", in.snr_db);
+    LOGD("elevation_deg=%f", in.elevation_deg);
+    LOGD("elevation_uncertainty_deg=%f", in.elevation_uncertainty_deg);
+    LOGD("azimuth_deg=%f", in.azimuth_deg);
+    LOGD("azimuth_uncertainty_deg=%f", in.azimuth_uncertainty_deg);
+    LOGD("used_in_fix=%d", in.used_in_fix);
+}
+
+void dump_gps_clock(gps_clock in) {
+    LOGD("===== dump_gps_clock ====");
+    LOGD("flags=0x%x", in.flags);
+    LOGD("leap_second=%d", in.leap_second);
+    LOGD("type=%d", in.type);
+    LOGD("time_ns=%"PRId64, in.time_ns);
+    LOGD("time_uncertainty_ns=%f", in.time_uncertainty_ns);
+    LOGD("full_bias_ns=%"PRId64, in.full_bias_ns);
+    LOGD("bias_ns=%f", in.bias_ns);
+    LOGD("bias_uncertainty_ns=%f", in.bias_uncertainty_ns);
+    LOGD("drift_nsps=%f", in.drift_nsps);
+    LOGD("drift_uncertainty_nsps=%f", in.drift_uncertainty_nsps);
+}
+
+void dump_gps_data(gps_data in) {
+    size_t i = 0;
+    LOGD("===== dump_gps_data ====");
+    LOGD("measurement_count=%zu", in.measurement_count);
+    for (i = 0; i < in.measurement_count; i++) {
+        LOGD("i=%zu", i);
+        dump_gps_measurement(in.measurements[i]);
+    }
+    dump_gps_clock(in.clock);
+}
+
+void dump_gps_nav_msg(gps_nav_msg in) {
+    LOGD("===== dump_gps_nav_msg ====");
+    LOGD("prn=%d", in.prn);
+    LOGD("type=%d", in.type);
+    LOGD("status=0x%x", in.status);
+    LOGD("message_id=%d", in.message_id);
+    LOGD("submessage_id=%d", in.submessage_id);
+    LOGD("data_length=%zu", in.data_length);
+}
+
+void dump_gnss_data(gnss_data in) {
+    size_t i = 0;
+    LOGD("===== dump_gnss_data ====");
+    LOGD("measurement_count=%zu", in.measurement_count);
+    for (i = 0; i < in.measurement_count; i++) {
+        LOGD("i=%zu", i);
+        dump_gnss_measurement(in.measurements[i]);
+    }
+    dump_gnss_clock(in.clock);
+}
+
+void dump_gnss_measurement(gnss_measurement in) {
+    LOGD("===== dump_gnss_measurement ====");
+    LOGD("flags=0x%x", in.flags);
+    LOGD("svid=%d", in.svid);
+    LOGD("constellation=0x%x", in.constellation);
+    LOGD("time_offset_ns=%f", in.time_offset_ns);
+    LOGD("state=0x%x", in.state);
+    LOGD("received_gps_tow_ns=%"PRId64, in.received_sv_time_in_ns);
+    LOGD("received_gps_tow_uncertainty_ns=%"PRId64, in.received_sv_time_uncertainty_in_ns);
+    LOGD("c_n0_dbhz=%f", in.c_n0_dbhz);
+    LOGD("pseudorange_rate_mps=%f", in.pseudorange_rate_mps);
+    LOGD("pseudorange_rate_uncertainty_mps=%f", in.pseudorange_rate_uncertainty_mps);
+    LOGD("accumulated_delta_range_state=0x%x", in.accumulated_delta_range_state);
+    LOGD("accumulated_delta_range_m=%f", in.accumulated_delta_range_m);
+    LOGD("accumulated_delta_range_uncertainty_m=%f", in.accumulated_delta_range_uncertainty_m);;
+    LOGD("carrier_frequency_hz=%f", in.carrier_frequency_hz);
+    LOGD("carrier_cycles=%"PRId64, in.carrier_cycles);
+    LOGD("carrier_phase=%f", in.carrier_phase);
+    LOGD("carrier_phase_uncertainty=%f", in.carrier_phase_uncertainty);
+    LOGD("multipath_indicator=%d", in.multipath_indicator);
+    LOGD("snr_db=%f", in.snr_db);
+}
+
+void dump_gnss_clock(gnss_clock in) {
+    LOGD("===== dump_gnss_clock ====");
+    LOGD("flags=0x%x", in.flags);
+    LOGD("leap_second=%d", in.leap_second);
+    LOGD("time_ns=%"PRId64, in.time_ns);
+    LOGD("time_uncertainty_ns=%f", in.time_uncertainty_ns);
+    LOGD("full_bias_ns=%"PRId64, in.full_bias_ns);
+    LOGD("bias_ns=%f", in.bias_ns);
+    LOGD("bias_uncertainty_ns=%f", in.bias_uncertainty_ns);
+    LOGD("drift_nsps=%f", in.drift_nsps);
+    LOGD("drift_uncertainty_nsps=%f", in.drift_uncertainty_nsps);
+    LOGD("hw_clock_discontinuity_count=%d", in.hw_clock_discontinuity_count);
+}
+
+void dump_gnss_nav_msg(gnss_nav_msg in) {
+    LOGD("===== dump_gnss_nav_msg ====");
+    LOGD("svid=%d", in.svid);
+    LOGD("type=%d", in.type);
+    LOGD("status=0x%x", in.status);
+    LOGD("message_id=%d", in.message_id);
+    LOGD("submessage_id=%d", in.submessage_id);
+    LOGD("data_length=%zu", in.data_length);
+}
+#endif
diff --git a/src/connectivity/gps/gps_hal/src/mtk_auto_log.c b/src/connectivity/gps/gps_hal/src/mtk_auto_log.c
new file mode 100644
index 0000000..33ab38f
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/src/mtk_auto_log.c
@@ -0,0 +1,109 @@
+/*
+* Copyright Statement:
+*
+* This software/firmware and related documentation ("MediaTek Software") are
+* protected under relevant copyright laws. The information contained herein is
+* confidential and proprietary to MediaTek Inc. and/or its licensors. Without
+* the prior written permission of MediaTek inc. and/or its licensors, any
+* reproduction, modification, use or disclosure of MediaTek Software, and
+* information contained herein, in whole or in part, shall be strictly
+* prohibited.
+*
+* MediaTek Inc. (C) 2017. All rights reserved.
+*
+* BY OPENING THIS FILE, RECEIVER HEREBY UNEQUIVOCALLY ACKNOWLEDGES AND AGREES
+* THAT THE SOFTWARE/FIRMWARE AND ITS DOCUMENTATIONS ("MEDIATEK SOFTWARE")
+* RECEIVED FROM MEDIATEK AND/OR ITS REPRESENTATIVES ARE PROVIDED TO RECEIVER
+* ON AN "AS-IS" BASIS ONLY. MEDIATEK EXPRESSLY DISCLAIMS ANY AND ALL
+* WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED
+* WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR
+* NONINFRINGEMENT. NEITHER DOES MEDIATEK PROVIDE ANY WARRANTY WHATSOEVER WITH
+* RESPECT TO THE SOFTWARE OF ANY THIRD PARTY WHICH MAY BE USED BY,
+* INCORPORATED IN, OR SUPPLIED WITH THE MEDIATEK SOFTWARE, AND RECEIVER AGREES
+* TO LOOK ONLY TO SUCH THIRD PARTY FOR ANY WARRANTY CLAIM RELATING THERETO.
+* RECEIVER EXPRESSLY ACKNOWLEDGES THAT IT IS RECEIVER'S SOLE RESPONSIBILITY TO
+* OBTAIN FROM ANY THIRD PARTY ALL PROPER LICENSES CONTAINED IN MEDIATEK
+* SOFTWARE. MEDIATEK SHALL ALSO NOT BE RESPONSIBLE FOR ANY MEDIATEK SOFTWARE
+* RELEASES MADE TO RECEIVER'S SPECIFICATION OR TO CONFORM TO A PARTICULAR
+* STANDARD OR OPEN FORUM. RECEIVER'S SOLE AND EXCLUSIVE REMEDY AND MEDIATEK'S
+* ENTIRE AND CUMULATIVE LIABILITY WITH RESPECT TO THE MEDIATEK SOFTWARE
+* RELEASED HEREUNDER WILL BE, AT MEDIATEK'S OPTION, TO REVISE OR REPLACE THE
+* MEDIATEK SOFTWARE AT ISSUE, OR REFUND ANY SOFTWARE LICENSE FEES OR SERVICE
+* CHARGE PAID BY RECEIVER TO MEDIATEK FOR SUCH MEDIATEK SOFTWARE AT ISSUE.
+*/
+#include <sys/time.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <time.h>
+#include <memory.h>
+
+#include "mtk_auto_log.h"
+
+#if defined(__LINUX_OS__)
+// -1 means failure
+int get_time_str(char* buf, int len) {
+    struct timeval  tv;
+    struct timezone tz;
+    struct tm      *tm;
+
+    gettimeofday(&tv, &tz);
+    tm = localtime(&tv.tv_sec);
+
+    memset(buf, 0, len);
+    sprintf(buf, "%04d/%02d/%02d %02d:%02d:%02d.%03d",
+        tm->tm_year + 1900, 1 + tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min,
+        tm->tm_sec, (int)(tv.tv_usec / 1000));
+
+    return 0;
+}
+#endif
+
+int set_log_level(int *dst_level, int src_level)
+{
+#if defined(__ANDROID_OS__)
+
+    ALOGI("Current debug level=%d", *dst_level);
+
+    if (src_level < L_VERBOSE || src_level >  L_SUPPRESS)
+    {
+        ALOGE("Invalid debug level, level=%d", src_level);
+        ALOGE("  [level] -");
+        ALOGE("  QUIET      = 6");
+        ALOGE("  ASSERT     = 5");
+        ALOGE("  ERROR      = 4");
+        ALOGE("  WARNING    = 3");
+        ALOGE("  INFO       = 2");
+        ALOGE("  DEBUG      = 1");
+        ALOGE("  LOGALL     = 0");
+        return -1;
+    }
+
+    *dst_level = src_level;
+
+    ALOGI("New debug level=%d", *dst_level);
+
+#elif defined(__LINUX_OS__)
+
+    printf("Current debug level=%d\n", *dst_level);
+
+    if (src_level < L_VERBOSE || src_level >  L_SUPPRESS)
+    {
+        printf("Invalid debug level, level=%d\n", src_level);
+        printf("  [level] -\n");
+        printf("  QUIET      = 6\n");
+        printf("  ASSERT     = 5\n");
+        printf("  ERROR      = 4\n");
+        printf("  WARNING    = 3\n");
+        printf("  INFO       = 2\n");
+        printf("  DEBUG      = 1\n");
+        printf("  LOGALL     = 0\n");
+        return -1;
+    }
+
+    *dst_level = src_level;
+
+    printf("New debug level=%d\n", *dst_level);
+
+#endif
+    return 0;
+}
diff --git a/src/connectivity/gps/gps_hal/src/mtk_lbs_utility.c b/src/connectivity/gps/gps_hal/src/mtk_lbs_utility.c
new file mode 100644
index 0000000..cd51ad9
--- /dev/null
+++ b/src/connectivity/gps/gps_hal/src/mtk_lbs_utility.c
@@ -0,0 +1,296 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <sys/time.h>
+#include <time.h>
+#include <stddef.h>  // offsetof
+#include <stdarg.h>
+#include <sys/stat.h>
+#include <unistd.h>  // usleep
+#include <sys/socket.h>
+#include <string.h>
+#include <fcntl.h>
+#include <arpa/inet.h>  // inet_addr
+#include <sys/un.h>  // struct sockaddr_un
+#include <pthread.h>
+#include <sys/epoll.h>
+#include <signal.h>
+#include <semaphore.h>
+
+#include "mtk_lbs_utility.h"
+#include "mtk_auto_log.h"
+
+#ifdef LOG_TAG
+#undef LOG_TAG
+#define LOG_TAG "mtk_lbs_utility"
+#endif
+
+void msleep(int interval) {
+    usleep(interval * 1000);
+}
+
+// in millisecond
+time_t get_tick() {
+    struct timespec ts;
+    if (clock_gettime(CLOCK_MONOTONIC, &ts) == -1) {
+        LOGE("clock_gettime failed reason=[%s]", strerror(errno));
+        return -1;
+    }
+    return (ts.tv_sec*1000) + (ts.tv_nsec/1000000);
+}
+
+// in millisecond
+time_t get_time_in_millisecond() {
+    struct timespec ts;
+    if (clock_gettime(CLOCK_REALTIME, &ts) == -1) {
+        LOGE("get_time_in_millisecond  failed reason=[%s]", strerror(errno));
+        return -1;
+    }
+    return ((long long)ts.tv_sec*1000) + ((long long)ts.tv_nsec/1000000);
+}
+#ifdef __LINUX_OS__ 
+/*************************************************
+* Timer
+**************************************************/
+// -1 means failure
+timer_t init_timer_id(timer_callback cb, int id) {
+    struct sigevent sevp;
+    timer_t timerid;
+
+    memset(&sevp, 0, sizeof(sevp));
+    sevp.sigev_value.sival_int = id;
+    sevp.sigev_notify = SIGEV_THREAD;
+    sevp.sigev_notify_function = cb;
+
+    if (timer_create(CLOCK_MONOTONIC, &sevp, &timerid) == -1) {
+        LOGE("timer_create  failed reason=[%s]", strerror(errno));
+        return (timer_t)-1;
+    }
+    return timerid;
+}
+
+// -1 means failure
+timer_t init_timer(timer_callback cb) {
+    return init_timer_id(cb, 0);
+}
+
+// -1 means failure
+int start_timer(timer_t timerid, int milliseconds) {
+    struct itimerspec expire;
+    expire.it_interval.tv_sec = 0;
+    expire.it_interval.tv_nsec = 0;
+    expire.it_value.tv_sec = milliseconds/1000;
+    expire.it_value.tv_nsec = (milliseconds%1000)*1000000;
+    return timer_settime(timerid, 0, &expire, NULL);
+}
+
+// -1 means failure
+int stop_timer(timer_t timerid) {
+    return start_timer(timerid, 0);
+}
+
+// -1 means failure
+int deinit_timer(timer_t timerid) {
+    if (timer_delete(timerid) == -1) {
+        // errno
+        return -1;
+    }
+    return 0;
+}
+
+#endif
+/*************************************************
+* Epoll
+**************************************************/
+// -1 means failure
+int epoll_add_fd(int epfd, int fd) {
+    struct epoll_event ev;
+    memset(&ev, 0, sizeof(ev));
+    ev.data.fd = fd;
+    ev.events = EPOLLIN;
+    // don't set the fd to edge trigger
+    // the some event like accept may be lost if two or more clients are connecting to server at the same time
+    // level trigger is preferred to avoid event lost
+    // do not set EPOLLOUT due to it will always trigger when write is available
+    if (epoll_ctl(epfd, EPOLL_CTL_ADD, fd, &ev) == -1) {
+        LOGE("epoll_add_fd() epoll_ctl() failed reason=[%s]%d epfd=%d fd=%d",
+            strerror(errno), errno, epfd, fd);
+        return -1;
+    }
+    return 0;
+}
+
+// -1 failed
+int epoll_add_fd2(int epfd, int fd, uint32_t events) {
+    struct epoll_event ev;
+    memset(&ev, 0, sizeof(ev));
+    ev.data.fd = fd;
+    ev.events = events;
+    // don't set the fd to edge trigger
+    // the some event like accept may be lost if two or more clients are connecting to server at the same time
+    // level trigger is preferred to avoid event lost
+    // do not set EPOLLOUT due to it will always trigger when write is available
+    if (epoll_ctl(epfd, EPOLL_CTL_ADD, fd, &ev) == -1) {
+        LOGE("epoll_add_fd2() epoll_ctl() failed reason=[%s]%d epfd=%d fd=%d",
+            strerror(errno), errno, epfd, fd);
+        return -1;
+    }
+    return 0;
+}
+
+int epoll_del_fd(int epfd, int fd) {
+    struct epoll_event  ev;
+    int                 ret;
+
+    if (epfd == -1)
+        return -1;
+
+    ev.events  = EPOLLIN;
+    ev.data.fd = fd;
+    do {
+        ret = epoll_ctl(epfd, EPOLL_CTL_DEL, fd, &ev);
+    } while (ret < 0 && errno == EINTR);
+    return ret;
+}
+
+// -1 failed
+int epoll_mod_fd(int epfd, int fd, uint32_t events) {
+    struct epoll_event ev;
+    memset(&ev, 0, sizeof(ev));
+    ev.data.fd = fd;
+    ev.events = events;
+    if (epoll_ctl(epfd, EPOLL_CTL_MOD, fd, &ev) == -1) {
+        LOGE("epoll_mod_fd() epoll_ctl() failed reason=[%s]%d epfd=%d fd=%d",
+            strerror(errno), errno, epfd, fd);
+        return -1;
+    }
+    return 0;
+}
+
+/*************************************************
+* Local UDP Socket
+**************************************************/
+// -1 means failure
+int socket_bind_udp(const char* path) {
+    int fd;
+    struct sockaddr_un addr;
+
+    fd = socket(PF_LOCAL, SOCK_DGRAM, 0);
+    if (fd < 0) {
+        LOGE("socket_bind_udp() socket() failed reason=[%s]%d",
+            strerror(errno), errno);
+        return -1;
+    }
+    LOGD("fd=%d,path=%s\n", fd, path);
+
+    memset(&addr, 0, sizeof(addr));
+    addr.sun_path[0] = 0;
+    MNLD_STRNCPY(addr.sun_path + 1, path,sizeof(addr.sun_path) - 1);
+    addr.sun_family = AF_UNIX;
+    unlink(path);
+
+    if (bind(fd, (const struct sockaddr *)&addr, sizeof(addr)) < 0) {
+        LOGE("socket_bind_udp() bind() failed path=[%s] reason=[%s]%d",
+            addr.sun_path+1, strerror(errno), errno);
+        close(fd);
+        return -1;
+    }else
+        LOGI("bind ok path=[%s]", addr.sun_path+1);
+    return fd;
+}
+
+// -1 means failure
+int socket_set_blocking(int fd, int blocking) {
+    if (fd < 0) {
+        LOGE("socket_set_blocking() invalid fd=%d", fd);
+        return -1;
+    }
+
+    int flags = fcntl(fd, F_GETFL, 0);
+    if (flags == -1) {
+        LOGE("socket_set_blocking() fcntl() failed invalid flags=%d reason=[%s]%d",
+            flags, strerror(errno), errno);
+        return -1;
+    }
+
+    flags = blocking ? (flags&~O_NONBLOCK) : (flags|O_NONBLOCK);
+    return (fcntl(fd, F_SETFL, flags) == 0) ? 0 : -1;
+}
+
+// -1 means failure
+int safe_sendto(const char* path, const char* buff, int len) {
+    int ret = 0;
+    struct sockaddr_un addr;
+    int retry = 10;
+    int fd = socket(PF_LOCAL, SOCK_DGRAM, 0);
+    if (fd < 0) {
+        LOGE("safe_sendto() socket() failed reason=[%s]%d",
+            strerror(errno), errno);
+        return -1;
+    }
+
+    int flags = fcntl(fd, F_GETFL, 0);
+    if (fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1){
+        LOGE("fcntl failed reason=[%s]%d",
+                    strerror(errno), errno);
+
+        close(fd);
+        return -1;
+    }
+
+    memset(&addr, 0, sizeof(addr));
+    addr.sun_path[0] = 0;
+    MNLD_STRNCPY(addr.sun_path + 1, path,sizeof(addr.sun_path) - 1);
+    addr.sun_family = AF_UNIX;
+
+    while ((ret = sendto(fd, buff, len, 0,
+        (const struct sockaddr *)&addr, sizeof(addr))) == -1) {
+        if (errno == EINTR) {
+            LOGE("errno==EINTR\n");
+            continue;
+        }
+        if (errno == EAGAIN) {
+            if (retry-- > 0) {
+                usleep(100 * 1000);
+                LOGE("errno==EAGAIN\n");
+                continue;
+            }
+        }
+        LOGE("safe_sendto() sendto() failed path=[%s] ret=%d reason=[%s]%d",
+            path, ret, strerror(errno), errno);
+        break;
+    }
+
+    close(fd);
+    return ret;
+}
+
+// -1 means failure
+int safe_recvfrom(int fd, char* buff, int len) {
+    int ret = 0;
+    int retry = 10;
+    int flags = fcntl(fd, F_GETFL, 0);
+    if (fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1){
+        LOGE("fcntl failed reason=[%s]%d",
+                    strerror(errno), errno);
+
+        close(fd);
+        return -1;
+    }
+
+    while ((ret = recvfrom(fd, buff, len, 0,
+         NULL, NULL)) == -1) {
+        LOGW("safe_recvfrom() ret=%d len=%d", ret, len);
+        if (errno == EINTR) continue;
+        if (errno == EAGAIN) {
+            if (retry-- > 0) {
+                usleep(100 * 1000);
+                continue;
+            }
+        }
+        LOGE("safe_recvfrom() recvfrom() failed reason=[%s]%d",
+            strerror(errno), errno);
+        break;
+    }
+    return ret;
+}