[Feature]add MT2731_MP2_MR2_SVN388 baseline version
Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/drivers/input/touchscreen/ads7846.c b/src/kernel/linux/v4.14/drivers/input/touchscreen/ads7846.c
new file mode 100644
index 0000000..a2f45ae
--- /dev/null
+++ b/src/kernel/linux/v4.14/drivers/input/touchscreen/ads7846.c
@@ -0,0 +1,1509 @@
+/*
+ * ADS7846 based touchscreen and sensor driver
+ *
+ * Copyright (c) 2005 David Brownell
+ * Copyright (c) 2006 Nokia Corporation
+ * Various changes: Imre Deak <imre.deak@nokia.com>
+ *
+ * Using code from:
+ * - corgi_ts.c
+ * Copyright (C) 2004-2005 Richard Purdie
+ * - omap_ts.[hc], ads7846.h, ts_osk.c
+ * Copyright (C) 2002 MontaVista Software
+ * Copyright (C) 2004 Texas Instruments
+ * Copyright (C) 2005 Dirk Behme
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/types.h>
+#include <linux/hwmon.h>
+#include <linux/err.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/pm.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/of_device.h>
+#include <linux/gpio.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/ads7846.h>
+#include <linux/regulator/consumer.h>
+#include <linux/module.h>
+#include <asm/irq.h>
+
+/*
+ * This code has been heavily tested on a Nokia 770, and lightly
+ * tested on other ads7846 devices (OSK/Mistral, Lubbock, Spitz).
+ * TSC2046 is just newer ads7846 silicon.
+ * Support for ads7843 tested on Atmel at91sam926x-EK.
+ * Support for ads7845 has only been stubbed in.
+ * Support for Analog Devices AD7873 and AD7843 tested.
+ *
+ * IRQ handling needs a workaround because of a shortcoming in handling
+ * edge triggered IRQs on some platforms like the OMAP1/2. These
+ * platforms don't handle the ARM lazy IRQ disabling properly, thus we
+ * have to maintain our own SW IRQ disabled status. This should be
+ * removed as soon as the affected platform's IRQ handling is fixed.
+ *
+ * App note sbaa036 talks in more detail about accurate sampling...
+ * that ought to help in situations like LCDs inducing noise (which
+ * can also be helped by using synch signals) and more generally.
+ * This driver tries to utilize the measures described in the app
+ * note. The strength of filtering can be set in the board-* specific
+ * files.
+ */
+
+#define TS_POLL_DELAY 1 /* ms delay before the first sample */
+#define TS_POLL_PERIOD 5 /* ms delay between samples */
+
+/* this driver doesn't aim at the peak continuous sample rate */
+#define SAMPLE_BITS (8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after */)
+
+struct ts_event {
+ /*
+ * For portability, we can't read 12 bit values using SPI (which
+ * would make the controller deliver them as native byte order u16
+ * with msbs zeroed). Instead, we read them as two 8-bit values,
+ * *** WHICH NEED BYTESWAPPING *** and range adjustment.
+ */
+ u16 x;
+ u16 y;
+ u16 z1, z2;
+ bool ignore;
+ u8 x_buf[3];
+ u8 y_buf[3];
+};
+
+/*
+ * We allocate this separately to avoid cache line sharing issues when
+ * driver is used with DMA-based SPI controllers (like atmel_spi) on
+ * systems where main memory is not DMA-coherent (most non-x86 boards).
+ */
+struct ads7846_packet {
+ u8 read_x, read_y, read_z1, read_z2, pwrdown;
+ u16 dummy; /* for the pwrdown read */
+ struct ts_event tc;
+ /* for ads7845 with mpc5121 psc spi we use 3-byte buffers */
+ u8 read_x_cmd[3], read_y_cmd[3], pwrdown_cmd[3];
+};
+
+struct ads7846 {
+ struct input_dev *input;
+ char phys[32];
+ char name[32];
+
+ struct spi_device *spi;
+ struct regulator *reg;
+
+#if IS_ENABLED(CONFIG_HWMON)
+ struct device *hwmon;
+#endif
+
+ u16 model;
+ u16 vref_mv;
+ u16 vref_delay_usecs;
+ u16 x_plate_ohms;
+ u16 pressure_max;
+
+ bool swap_xy;
+ bool use_internal;
+
+ struct ads7846_packet *packet;
+
+ struct spi_transfer xfer[18];
+ struct spi_message msg[5];
+ int msg_count;
+ wait_queue_head_t wait;
+
+ bool pendown;
+
+ int read_cnt;
+ int read_rep;
+ int last_read;
+
+ u16 debounce_max;
+ u16 debounce_tol;
+ u16 debounce_rep;
+
+ u16 penirq_recheck_delay_usecs;
+
+ struct mutex lock;
+ bool stopped; /* P: lock */
+ bool disabled; /* P: lock */
+ bool suspended; /* P: lock */
+
+ int (*filter)(void *data, int data_idx, int *val);
+ void *filter_data;
+ void (*filter_cleanup)(void *data);
+ int (*get_pendown_state)(void);
+ int gpio_pendown;
+
+ void (*wait_for_sync)(void);
+};
+
+/* leave chip selected when we're done, for quicker re-select? */
+#if 0
+#define CS_CHANGE(xfer) ((xfer).cs_change = 1)
+#else
+#define CS_CHANGE(xfer) ((xfer).cs_change = 0)
+#endif
+
+/*--------------------------------------------------------------------------*/
+
+/* The ADS7846 has touchscreen and other sensors.
+ * Earlier ads784x chips are somewhat compatible.
+ */
+#define ADS_START (1 << 7)
+#define ADS_A2A1A0_d_y (1 << 4) /* differential */
+#define ADS_A2A1A0_d_z1 (3 << 4) /* differential */
+#define ADS_A2A1A0_d_z2 (4 << 4) /* differential */
+#define ADS_A2A1A0_d_x (5 << 4) /* differential */
+#define ADS_A2A1A0_temp0 (0 << 4) /* non-differential */
+#define ADS_A2A1A0_vbatt (2 << 4) /* non-differential */
+#define ADS_A2A1A0_vaux (6 << 4) /* non-differential */
+#define ADS_A2A1A0_temp1 (7 << 4) /* non-differential */
+#define ADS_8_BIT (1 << 3)
+#define ADS_12_BIT (0 << 3)
+#define ADS_SER (1 << 2) /* non-differential */
+#define ADS_DFR (0 << 2) /* differential */
+#define ADS_PD10_PDOWN (0 << 0) /* low power mode + penirq */
+#define ADS_PD10_ADC_ON (1 << 0) /* ADC on */
+#define ADS_PD10_REF_ON (2 << 0) /* vREF on + penirq */
+#define ADS_PD10_ALL_ON (3 << 0) /* ADC + vREF on */
+
+#define MAX_12BIT ((1<<12)-1)
+
+/* leave ADC powered up (disables penirq) between differential samples */
+#define READ_12BIT_DFR(x, adc, vref) (ADS_START | ADS_A2A1A0_d_ ## x \
+ | ADS_12_BIT | ADS_DFR | \
+ (adc ? ADS_PD10_ADC_ON : 0) | (vref ? ADS_PD10_REF_ON : 0))
+
+#define READ_Y(vref) (READ_12BIT_DFR(y, 1, vref))
+#define READ_Z1(vref) (READ_12BIT_DFR(z1, 1, vref))
+#define READ_Z2(vref) (READ_12BIT_DFR(z2, 1, vref))
+
+#define READ_X(vref) (READ_12BIT_DFR(x, 1, vref))
+#define PWRDOWN (READ_12BIT_DFR(y, 0, 0)) /* LAST */
+
+/* single-ended samples need to first power up reference voltage;
+ * we leave both ADC and VREF powered
+ */
+#define READ_12BIT_SER(x) (ADS_START | ADS_A2A1A0_ ## x \
+ | ADS_12_BIT | ADS_SER)
+
+#define REF_ON (READ_12BIT_DFR(x, 1, 1))
+#define REF_OFF (READ_12BIT_DFR(y, 0, 0))
+
+/* Must be called with ts->lock held */
+static void ads7846_stop(struct ads7846 *ts)
+{
+ if (!ts->disabled && !ts->suspended) {
+ /* Signal IRQ thread to stop polling and disable the handler. */
+ ts->stopped = true;
+ mb();
+ wake_up(&ts->wait);
+ disable_irq(ts->spi->irq);
+ }
+}
+
+/* Must be called with ts->lock held */
+static void ads7846_restart(struct ads7846 *ts)
+{
+ if (!ts->disabled && !ts->suspended) {
+ /* Tell IRQ thread that it may poll the device. */
+ ts->stopped = false;
+ mb();
+ enable_irq(ts->spi->irq);
+ }
+}
+
+/* Must be called with ts->lock held */
+static void __ads7846_disable(struct ads7846 *ts)
+{
+ ads7846_stop(ts);
+ regulator_disable(ts->reg);
+
+ /*
+ * We know the chip's in low power mode since we always
+ * leave it that way after every request
+ */
+}
+
+/* Must be called with ts->lock held */
+static void __ads7846_enable(struct ads7846 *ts)
+{
+ int error;
+
+ error = regulator_enable(ts->reg);
+ if (error != 0)
+ dev_err(&ts->spi->dev, "Failed to enable supply: %d\n", error);
+
+ ads7846_restart(ts);
+}
+
+static void ads7846_disable(struct ads7846 *ts)
+{
+ mutex_lock(&ts->lock);
+
+ if (!ts->disabled) {
+
+ if (!ts->suspended)
+ __ads7846_disable(ts);
+
+ ts->disabled = true;
+ }
+
+ mutex_unlock(&ts->lock);
+}
+
+static void ads7846_enable(struct ads7846 *ts)
+{
+ mutex_lock(&ts->lock);
+
+ if (ts->disabled) {
+
+ ts->disabled = false;
+
+ if (!ts->suspended)
+ __ads7846_enable(ts);
+ }
+
+ mutex_unlock(&ts->lock);
+}
+
+/*--------------------------------------------------------------------------*/
+
+/*
+ * Non-touchscreen sensors only use single-ended conversions.
+ * The range is GND..vREF. The ads7843 and ads7835 must use external vREF;
+ * ads7846 lets that pin be unconnected, to use internal vREF.
+ */
+
+struct ser_req {
+ u8 ref_on;
+ u8 command;
+ u8 ref_off;
+ u16 scratch;
+ struct spi_message msg;
+ struct spi_transfer xfer[6];
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+ __be16 sample ____cacheline_aligned;
+};
+
+struct ads7845_ser_req {
+ u8 command[3];
+ struct spi_message msg;
+ struct spi_transfer xfer[2];
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+ u8 sample[3] ____cacheline_aligned;
+};
+
+static int ads7846_read12_ser(struct device *dev, unsigned command)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ struct ads7846 *ts = dev_get_drvdata(dev);
+ struct ser_req *req;
+ int status;
+
+ req = kzalloc(sizeof *req, GFP_KERNEL);
+ if (!req)
+ return -ENOMEM;
+
+ spi_message_init(&req->msg);
+
+ /* maybe turn on internal vREF, and let it settle */
+ if (ts->use_internal) {
+ req->ref_on = REF_ON;
+ req->xfer[0].tx_buf = &req->ref_on;
+ req->xfer[0].len = 1;
+ spi_message_add_tail(&req->xfer[0], &req->msg);
+
+ req->xfer[1].rx_buf = &req->scratch;
+ req->xfer[1].len = 2;
+
+ /* for 1uF, settle for 800 usec; no cap, 100 usec. */
+ req->xfer[1].delay_usecs = ts->vref_delay_usecs;
+ spi_message_add_tail(&req->xfer[1], &req->msg);
+
+ /* Enable reference voltage */
+ command |= ADS_PD10_REF_ON;
+ }
+
+ /* Enable ADC in every case */
+ command |= ADS_PD10_ADC_ON;
+
+ /* take sample */
+ req->command = (u8) command;
+ req->xfer[2].tx_buf = &req->command;
+ req->xfer[2].len = 1;
+ spi_message_add_tail(&req->xfer[2], &req->msg);
+
+ req->xfer[3].rx_buf = &req->sample;
+ req->xfer[3].len = 2;
+ spi_message_add_tail(&req->xfer[3], &req->msg);
+
+ /* REVISIT: take a few more samples, and compare ... */
+
+ /* converter in low power mode & enable PENIRQ */
+ req->ref_off = PWRDOWN;
+ req->xfer[4].tx_buf = &req->ref_off;
+ req->xfer[4].len = 1;
+ spi_message_add_tail(&req->xfer[4], &req->msg);
+
+ req->xfer[5].rx_buf = &req->scratch;
+ req->xfer[5].len = 2;
+ CS_CHANGE(req->xfer[5]);
+ spi_message_add_tail(&req->xfer[5], &req->msg);
+
+ mutex_lock(&ts->lock);
+ ads7846_stop(ts);
+ status = spi_sync(spi, &req->msg);
+ ads7846_restart(ts);
+ mutex_unlock(&ts->lock);
+
+ if (status == 0) {
+ /* on-wire is a must-ignore bit, a BE12 value, then padding */
+ status = be16_to_cpu(req->sample);
+ status = status >> 3;
+ status &= 0x0fff;
+ }
+
+ kfree(req);
+ return status;
+}
+
+static int ads7845_read12_ser(struct device *dev, unsigned command)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ struct ads7846 *ts = dev_get_drvdata(dev);
+ struct ads7845_ser_req *req;
+ int status;
+
+ req = kzalloc(sizeof *req, GFP_KERNEL);
+ if (!req)
+ return -ENOMEM;
+
+ spi_message_init(&req->msg);
+
+ req->command[0] = (u8) command;
+ req->xfer[0].tx_buf = req->command;
+ req->xfer[0].rx_buf = req->sample;
+ req->xfer[0].len = 3;
+ spi_message_add_tail(&req->xfer[0], &req->msg);
+
+ mutex_lock(&ts->lock);
+ ads7846_stop(ts);
+ status = spi_sync(spi, &req->msg);
+ ads7846_restart(ts);
+ mutex_unlock(&ts->lock);
+
+ if (status == 0) {
+ /* BE12 value, then padding */
+ status = be16_to_cpu(*((u16 *)&req->sample[1]));
+ status = status >> 3;
+ status &= 0x0fff;
+ }
+
+ kfree(req);
+ return status;
+}
+
+#if IS_ENABLED(CONFIG_HWMON)
+
+#define SHOW(name, var, adjust) static ssize_t \
+name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \
+{ \
+ struct ads7846 *ts = dev_get_drvdata(dev); \
+ ssize_t v = ads7846_read12_ser(&ts->spi->dev, \
+ READ_12BIT_SER(var)); \
+ if (v < 0) \
+ return v; \
+ return sprintf(buf, "%u\n", adjust(ts, v)); \
+} \
+static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL);
+
+
+/* Sysfs conventions report temperatures in millidegrees Celsius.
+ * ADS7846 could use the low-accuracy two-sample scheme, but can't do the high
+ * accuracy scheme without calibration data. For now we won't try either;
+ * userspace sees raw sensor values, and must scale/calibrate appropriately.
+ */
+static inline unsigned null_adjust(struct ads7846 *ts, ssize_t v)
+{
+ return v;
+}
+
+SHOW(temp0, temp0, null_adjust) /* temp1_input */
+SHOW(temp1, temp1, null_adjust) /* temp2_input */
+
+
+/* sysfs conventions report voltages in millivolts. We can convert voltages
+ * if we know vREF. userspace may need to scale vAUX to match the board's
+ * external resistors; we assume that vBATT only uses the internal ones.
+ */
+static inline unsigned vaux_adjust(struct ads7846 *ts, ssize_t v)
+{
+ unsigned retval = v;
+
+ /* external resistors may scale vAUX into 0..vREF */
+ retval *= ts->vref_mv;
+ retval = retval >> 12;
+
+ return retval;
+}
+
+static inline unsigned vbatt_adjust(struct ads7846 *ts, ssize_t v)
+{
+ unsigned retval = vaux_adjust(ts, v);
+
+ /* ads7846 has a resistor ladder to scale this signal down */
+ if (ts->model == 7846)
+ retval *= 4;
+
+ return retval;
+}
+
+SHOW(in0_input, vaux, vaux_adjust)
+SHOW(in1_input, vbatt, vbatt_adjust)
+
+static umode_t ads7846_is_visible(struct kobject *kobj, struct attribute *attr,
+ int index)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct ads7846 *ts = dev_get_drvdata(dev);
+
+ if (ts->model == 7843 && index < 2) /* in0, in1 */
+ return 0;
+ if (ts->model == 7845 && index != 2) /* in0 */
+ return 0;
+
+ return attr->mode;
+}
+
+static struct attribute *ads7846_attributes[] = {
+ &dev_attr_temp0.attr, /* 0 */
+ &dev_attr_temp1.attr, /* 1 */
+ &dev_attr_in0_input.attr, /* 2 */
+ &dev_attr_in1_input.attr, /* 3 */
+ NULL,
+};
+
+static const struct attribute_group ads7846_attr_group = {
+ .attrs = ads7846_attributes,
+ .is_visible = ads7846_is_visible,
+};
+__ATTRIBUTE_GROUPS(ads7846_attr);
+
+static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts)
+{
+ /* hwmon sensors need a reference voltage */
+ switch (ts->model) {
+ case 7846:
+ if (!ts->vref_mv) {
+ dev_dbg(&spi->dev, "assuming 2.5V internal vREF\n");
+ ts->vref_mv = 2500;
+ ts->use_internal = true;
+ }
+ break;
+ case 7845:
+ case 7843:
+ if (!ts->vref_mv) {
+ dev_warn(&spi->dev,
+ "external vREF for ADS%d not specified\n",
+ ts->model);
+ return 0;
+ }
+ break;
+ }
+
+ ts->hwmon = hwmon_device_register_with_groups(&spi->dev, spi->modalias,
+ ts, ads7846_attr_groups);
+
+ return PTR_ERR_OR_ZERO(ts->hwmon);
+}
+
+static void ads784x_hwmon_unregister(struct spi_device *spi,
+ struct ads7846 *ts)
+{
+ if (ts->hwmon)
+ hwmon_device_unregister(ts->hwmon);
+}
+
+#else
+static inline int ads784x_hwmon_register(struct spi_device *spi,
+ struct ads7846 *ts)
+{
+ return 0;
+}
+
+static inline void ads784x_hwmon_unregister(struct spi_device *spi,
+ struct ads7846 *ts)
+{
+}
+#endif
+
+static ssize_t ads7846_pen_down_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ads7846 *ts = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%u\n", ts->pendown);
+}
+
+static DEVICE_ATTR(pen_down, S_IRUGO, ads7846_pen_down_show, NULL);
+
+static ssize_t ads7846_disable_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ads7846 *ts = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%u\n", ts->disabled);
+}
+
+static ssize_t ads7846_disable_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ads7846 *ts = dev_get_drvdata(dev);
+ unsigned int i;
+ int err;
+
+ err = kstrtouint(buf, 10, &i);
+ if (err)
+ return err;
+
+ if (i)
+ ads7846_disable(ts);
+ else
+ ads7846_enable(ts);
+
+ return count;
+}
+
+static DEVICE_ATTR(disable, 0664, ads7846_disable_show, ads7846_disable_store);
+
+static struct attribute *ads784x_attributes[] = {
+ &dev_attr_pen_down.attr,
+ &dev_attr_disable.attr,
+ NULL,
+};
+
+static const struct attribute_group ads784x_attr_group = {
+ .attrs = ads784x_attributes,
+};
+
+/*--------------------------------------------------------------------------*/
+
+static int get_pendown_state(struct ads7846 *ts)
+{
+ if (ts->get_pendown_state)
+ return ts->get_pendown_state();
+
+ return !gpio_get_value(ts->gpio_pendown);
+}
+
+static void null_wait_for_sync(void)
+{
+}
+
+static int ads7846_debounce_filter(void *ads, int data_idx, int *val)
+{
+ struct ads7846 *ts = ads;
+
+ if (!ts->read_cnt || (abs(ts->last_read - *val) > ts->debounce_tol)) {
+ /* Start over collecting consistent readings. */
+ ts->read_rep = 0;
+ /*
+ * Repeat it, if this was the first read or the read
+ * wasn't consistent enough.
+ */
+ if (ts->read_cnt < ts->debounce_max) {
+ ts->last_read = *val;
+ ts->read_cnt++;
+ return ADS7846_FILTER_REPEAT;
+ } else {
+ /*
+ * Maximum number of debouncing reached and still
+ * not enough number of consistent readings. Abort
+ * the whole sample, repeat it in the next sampling
+ * period.
+ */
+ ts->read_cnt = 0;
+ return ADS7846_FILTER_IGNORE;
+ }
+ } else {
+ if (++ts->read_rep > ts->debounce_rep) {
+ /*
+ * Got a good reading for this coordinate,
+ * go for the next one.
+ */
+ ts->read_cnt = 0;
+ ts->read_rep = 0;
+ return ADS7846_FILTER_OK;
+ } else {
+ /* Read more values that are consistent. */
+ ts->read_cnt++;
+ return ADS7846_FILTER_REPEAT;
+ }
+ }
+}
+
+static int ads7846_no_filter(void *ads, int data_idx, int *val)
+{
+ return ADS7846_FILTER_OK;
+}
+
+static int ads7846_get_value(struct ads7846 *ts, struct spi_message *m)
+{
+ int value;
+ struct spi_transfer *t =
+ list_entry(m->transfers.prev, struct spi_transfer, transfer_list);
+
+ if (ts->model == 7845) {
+ value = be16_to_cpup((__be16 *)&(((char *)t->rx_buf)[1]));
+ } else {
+ /*
+ * adjust: on-wire is a must-ignore bit, a BE12 value, then
+ * padding; built from two 8 bit values written msb-first.
+ */
+ value = be16_to_cpup((__be16 *)t->rx_buf);
+ }
+
+ /* enforce ADC output is 12 bits width */
+ return (value >> 3) & 0xfff;
+}
+
+static void ads7846_update_value(struct spi_message *m, int val)
+{
+ struct spi_transfer *t =
+ list_entry(m->transfers.prev, struct spi_transfer, transfer_list);
+
+ *(u16 *)t->rx_buf = val;
+}
+
+static void ads7846_read_state(struct ads7846 *ts)
+{
+ struct ads7846_packet *packet = ts->packet;
+ struct spi_message *m;
+ int msg_idx = 0;
+ int val;
+ int action;
+ int error;
+
+ while (msg_idx < ts->msg_count) {
+
+ ts->wait_for_sync();
+
+ m = &ts->msg[msg_idx];
+ error = spi_sync(ts->spi, m);
+ if (error) {
+ dev_err(&ts->spi->dev, "spi_sync --> %d\n", error);
+ packet->tc.ignore = true;
+ return;
+ }
+
+ /*
+ * Last message is power down request, no need to convert
+ * or filter the value.
+ */
+ if (msg_idx < ts->msg_count - 1) {
+
+ val = ads7846_get_value(ts, m);
+
+ action = ts->filter(ts->filter_data, msg_idx, &val);
+ switch (action) {
+ case ADS7846_FILTER_REPEAT:
+ continue;
+
+ case ADS7846_FILTER_IGNORE:
+ packet->tc.ignore = true;
+ msg_idx = ts->msg_count - 1;
+ continue;
+
+ case ADS7846_FILTER_OK:
+ ads7846_update_value(m, val);
+ packet->tc.ignore = false;
+ msg_idx++;
+ break;
+
+ default:
+ BUG();
+ }
+ } else {
+ msg_idx++;
+ }
+ }
+}
+
+static void ads7846_report_state(struct ads7846 *ts)
+{
+ struct ads7846_packet *packet = ts->packet;
+ unsigned int Rt;
+ u16 x, y, z1, z2;
+
+ /*
+ * ads7846_get_value() does in-place conversion (including byte swap)
+ * from on-the-wire format as part of debouncing to get stable
+ * readings.
+ */
+ if (ts->model == 7845) {
+ x = *(u16 *)packet->tc.x_buf;
+ y = *(u16 *)packet->tc.y_buf;
+ z1 = 0;
+ z2 = 0;
+ } else {
+ x = packet->tc.x;
+ y = packet->tc.y;
+ z1 = packet->tc.z1;
+ z2 = packet->tc.z2;
+ }
+
+ /* range filtering */
+ if (x == MAX_12BIT)
+ x = 0;
+
+ if (ts->model == 7843) {
+ Rt = ts->pressure_max / 2;
+ } else if (ts->model == 7845) {
+ if (get_pendown_state(ts))
+ Rt = ts->pressure_max / 2;
+ else
+ Rt = 0;
+ dev_vdbg(&ts->spi->dev, "x/y: %d/%d, PD %d\n", x, y, Rt);
+ } else if (likely(x && z1)) {
+ /* compute touch pressure resistance using equation #2 */
+ Rt = z2;
+ Rt -= z1;
+ Rt *= x;
+ Rt *= ts->x_plate_ohms;
+ Rt /= z1;
+ Rt = (Rt + 2047) >> 12;
+ } else {
+ Rt = 0;
+ }
+
+ /*
+ * Sample found inconsistent by debouncing or pressure is beyond
+ * the maximum. Don't report it to user space, repeat at least
+ * once more the measurement
+ */
+ if (packet->tc.ignore || Rt > ts->pressure_max) {
+ dev_vdbg(&ts->spi->dev, "ignored %d pressure %d\n",
+ packet->tc.ignore, Rt);
+ return;
+ }
+
+ /*
+ * Maybe check the pendown state before reporting. This discards
+ * false readings when the pen is lifted.
+ */
+ if (ts->penirq_recheck_delay_usecs) {
+ udelay(ts->penirq_recheck_delay_usecs);
+ if (!get_pendown_state(ts))
+ Rt = 0;
+ }
+
+ /*
+ * NOTE: We can't rely on the pressure to determine the pen down
+ * state, even this controller has a pressure sensor. The pressure
+ * value can fluctuate for quite a while after lifting the pen and
+ * in some cases may not even settle at the expected value.
+ *
+ * The only safe way to check for the pen up condition is in the
+ * timer by reading the pen signal state (it's a GPIO _and_ IRQ).
+ */
+ if (Rt) {
+ struct input_dev *input = ts->input;
+
+ if (ts->swap_xy)
+ swap(x, y);
+
+ if (!ts->pendown) {
+ input_report_key(input, BTN_TOUCH, 1);
+ ts->pendown = true;
+ dev_vdbg(&ts->spi->dev, "DOWN\n");
+ }
+
+ input_report_abs(input, ABS_X, x);
+ input_report_abs(input, ABS_Y, y);
+ input_report_abs(input, ABS_PRESSURE, ts->pressure_max - Rt);
+
+ input_sync(input);
+ dev_vdbg(&ts->spi->dev, "%4d/%4d/%4d\n", x, y, Rt);
+ }
+}
+
+static irqreturn_t ads7846_hard_irq(int irq, void *handle)
+{
+ struct ads7846 *ts = handle;
+
+ return get_pendown_state(ts) ? IRQ_WAKE_THREAD : IRQ_HANDLED;
+}
+
+
+static irqreturn_t ads7846_irq(int irq, void *handle)
+{
+ struct ads7846 *ts = handle;
+
+ /* Start with a small delay before checking pendown state */
+ msleep(TS_POLL_DELAY);
+
+ while (!ts->stopped && get_pendown_state(ts)) {
+
+ /* pen is down, continue with the measurement */
+ ads7846_read_state(ts);
+
+ if (!ts->stopped)
+ ads7846_report_state(ts);
+
+ wait_event_timeout(ts->wait, ts->stopped,
+ msecs_to_jiffies(TS_POLL_PERIOD));
+ }
+
+ if (ts->pendown && !ts->stopped) {
+ struct input_dev *input = ts->input;
+
+ input_report_key(input, BTN_TOUCH, 0);
+ input_report_abs(input, ABS_PRESSURE, 0);
+ input_sync(input);
+
+ ts->pendown = false;
+ dev_vdbg(&ts->spi->dev, "UP\n");
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int __maybe_unused ads7846_suspend(struct device *dev)
+{
+ struct ads7846 *ts = dev_get_drvdata(dev);
+
+ mutex_lock(&ts->lock);
+
+ if (!ts->suspended) {
+
+ if (!ts->disabled)
+ __ads7846_disable(ts);
+
+ if (device_may_wakeup(&ts->spi->dev))
+ enable_irq_wake(ts->spi->irq);
+
+ ts->suspended = true;
+ }
+
+ mutex_unlock(&ts->lock);
+
+ return 0;
+}
+
+static int __maybe_unused ads7846_resume(struct device *dev)
+{
+ struct ads7846 *ts = dev_get_drvdata(dev);
+
+ mutex_lock(&ts->lock);
+
+ if (ts->suspended) {
+
+ ts->suspended = false;
+
+ if (device_may_wakeup(&ts->spi->dev))
+ disable_irq_wake(ts->spi->irq);
+
+ if (!ts->disabled)
+ __ads7846_enable(ts);
+ }
+
+ mutex_unlock(&ts->lock);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(ads7846_pm, ads7846_suspend, ads7846_resume);
+
+static int ads7846_setup_pendown(struct spi_device *spi,
+ struct ads7846 *ts,
+ const struct ads7846_platform_data *pdata)
+{
+ int err;
+
+ /*
+ * REVISIT when the irq can be triggered active-low, or if for some
+ * reason the touchscreen isn't hooked up, we don't need to access
+ * the pendown state.
+ */
+
+ if (pdata->get_pendown_state) {
+ ts->get_pendown_state = pdata->get_pendown_state;
+ } else if (gpio_is_valid(pdata->gpio_pendown)) {
+
+ err = gpio_request_one(pdata->gpio_pendown, GPIOF_IN,
+ "ads7846_pendown");
+ if (err) {
+ dev_err(&spi->dev,
+ "failed to request/setup pendown GPIO%d: %d\n",
+ pdata->gpio_pendown, err);
+ return err;
+ }
+
+ ts->gpio_pendown = pdata->gpio_pendown;
+
+ if (pdata->gpio_pendown_debounce)
+ gpio_set_debounce(pdata->gpio_pendown,
+ pdata->gpio_pendown_debounce);
+ } else {
+ dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/*
+ * Set up the transfers to read touchscreen state; this assumes we
+ * use formula #2 for pressure, not #3.
+ */
+static void ads7846_setup_spi_msg(struct ads7846 *ts,
+ const struct ads7846_platform_data *pdata)
+{
+ struct spi_message *m = &ts->msg[0];
+ struct spi_transfer *x = ts->xfer;
+ struct ads7846_packet *packet = ts->packet;
+ int vref = pdata->keep_vref_on;
+
+ if (ts->model == 7873) {
+ /*
+ * The AD7873 is almost identical to the ADS7846
+ * keep VREF off during differential/ratiometric
+ * conversion modes.
+ */
+ ts->model = 7846;
+ vref = 0;
+ }
+
+ ts->msg_count = 1;
+ spi_message_init(m);
+ m->context = ts;
+
+ if (ts->model == 7845) {
+ packet->read_y_cmd[0] = READ_Y(vref);
+ packet->read_y_cmd[1] = 0;
+ packet->read_y_cmd[2] = 0;
+ x->tx_buf = &packet->read_y_cmd[0];
+ x->rx_buf = &packet->tc.y_buf[0];
+ x->len = 3;
+ spi_message_add_tail(x, m);
+ } else {
+ /* y- still on; turn on only y+ (and ADC) */
+ packet->read_y = READ_Y(vref);
+ x->tx_buf = &packet->read_y;
+ x->len = 1;
+ spi_message_add_tail(x, m);
+
+ x++;
+ x->rx_buf = &packet->tc.y;
+ x->len = 2;
+ spi_message_add_tail(x, m);
+ }
+
+ /*
+ * The first sample after switching drivers can be low quality;
+ * optionally discard it, using a second one after the signals
+ * have had enough time to stabilize.
+ */
+ if (pdata->settle_delay_usecs) {
+ x->delay_usecs = pdata->settle_delay_usecs;
+
+ x++;
+ x->tx_buf = &packet->read_y;
+ x->len = 1;
+ spi_message_add_tail(x, m);
+
+ x++;
+ x->rx_buf = &packet->tc.y;
+ x->len = 2;
+ spi_message_add_tail(x, m);
+ }
+
+ ts->msg_count++;
+ m++;
+ spi_message_init(m);
+ m->context = ts;
+
+ if (ts->model == 7845) {
+ x++;
+ packet->read_x_cmd[0] = READ_X(vref);
+ packet->read_x_cmd[1] = 0;
+ packet->read_x_cmd[2] = 0;
+ x->tx_buf = &packet->read_x_cmd[0];
+ x->rx_buf = &packet->tc.x_buf[0];
+ x->len = 3;
+ spi_message_add_tail(x, m);
+ } else {
+ /* turn y- off, x+ on, then leave in lowpower */
+ x++;
+ packet->read_x = READ_X(vref);
+ x->tx_buf = &packet->read_x;
+ x->len = 1;
+ spi_message_add_tail(x, m);
+
+ x++;
+ x->rx_buf = &packet->tc.x;
+ x->len = 2;
+ spi_message_add_tail(x, m);
+ }
+
+ /* ... maybe discard first sample ... */
+ if (pdata->settle_delay_usecs) {
+ x->delay_usecs = pdata->settle_delay_usecs;
+
+ x++;
+ x->tx_buf = &packet->read_x;
+ x->len = 1;
+ spi_message_add_tail(x, m);
+
+ x++;
+ x->rx_buf = &packet->tc.x;
+ x->len = 2;
+ spi_message_add_tail(x, m);
+ }
+
+ /* turn y+ off, x- on; we'll use formula #2 */
+ if (ts->model == 7846) {
+ ts->msg_count++;
+ m++;
+ spi_message_init(m);
+ m->context = ts;
+
+ x++;
+ packet->read_z1 = READ_Z1(vref);
+ x->tx_buf = &packet->read_z1;
+ x->len = 1;
+ spi_message_add_tail(x, m);
+
+ x++;
+ x->rx_buf = &packet->tc.z1;
+ x->len = 2;
+ spi_message_add_tail(x, m);
+
+ /* ... maybe discard first sample ... */
+ if (pdata->settle_delay_usecs) {
+ x->delay_usecs = pdata->settle_delay_usecs;
+
+ x++;
+ x->tx_buf = &packet->read_z1;
+ x->len = 1;
+ spi_message_add_tail(x, m);
+
+ x++;
+ x->rx_buf = &packet->tc.z1;
+ x->len = 2;
+ spi_message_add_tail(x, m);
+ }
+
+ ts->msg_count++;
+ m++;
+ spi_message_init(m);
+ m->context = ts;
+
+ x++;
+ packet->read_z2 = READ_Z2(vref);
+ x->tx_buf = &packet->read_z2;
+ x->len = 1;
+ spi_message_add_tail(x, m);
+
+ x++;
+ x->rx_buf = &packet->tc.z2;
+ x->len = 2;
+ spi_message_add_tail(x, m);
+
+ /* ... maybe discard first sample ... */
+ if (pdata->settle_delay_usecs) {
+ x->delay_usecs = pdata->settle_delay_usecs;
+
+ x++;
+ x->tx_buf = &packet->read_z2;
+ x->len = 1;
+ spi_message_add_tail(x, m);
+
+ x++;
+ x->rx_buf = &packet->tc.z2;
+ x->len = 2;
+ spi_message_add_tail(x, m);
+ }
+ }
+
+ /* power down */
+ ts->msg_count++;
+ m++;
+ spi_message_init(m);
+ m->context = ts;
+
+ if (ts->model == 7845) {
+ x++;
+ packet->pwrdown_cmd[0] = PWRDOWN;
+ packet->pwrdown_cmd[1] = 0;
+ packet->pwrdown_cmd[2] = 0;
+ x->tx_buf = &packet->pwrdown_cmd[0];
+ x->len = 3;
+ } else {
+ x++;
+ packet->pwrdown = PWRDOWN;
+ x->tx_buf = &packet->pwrdown;
+ x->len = 1;
+ spi_message_add_tail(x, m);
+
+ x++;
+ x->rx_buf = &packet->dummy;
+ x->len = 2;
+ }
+
+ CS_CHANGE(*x);
+ spi_message_add_tail(x, m);
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id ads7846_dt_ids[] = {
+ { .compatible = "ti,tsc2046", .data = (void *) 7846 },
+ { .compatible = "ti,ads7843", .data = (void *) 7843 },
+ { .compatible = "ti,ads7845", .data = (void *) 7845 },
+ { .compatible = "ti,ads7846", .data = (void *) 7846 },
+ { .compatible = "ti,ads7873", .data = (void *) 7873 },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ads7846_dt_ids);
+
+static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev)
+{
+ struct ads7846_platform_data *pdata;
+ struct device_node *node = dev->of_node;
+ const struct of_device_id *match;
+
+ if (!node) {
+ dev_err(dev, "Device does not have associated DT data\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ match = of_match_device(ads7846_dt_ids, dev);
+ if (!match) {
+ dev_err(dev, "Unknown device model\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return ERR_PTR(-ENOMEM);
+
+ pdata->model = (unsigned long)match->data;
+
+ of_property_read_u16(node, "ti,vref-delay-usecs",
+ &pdata->vref_delay_usecs);
+ of_property_read_u16(node, "ti,vref-mv", &pdata->vref_mv);
+ pdata->keep_vref_on = of_property_read_bool(node, "ti,keep-vref-on");
+
+ pdata->swap_xy = of_property_read_bool(node, "ti,swap-xy");
+
+ of_property_read_u16(node, "ti,settle-delay-usec",
+ &pdata->settle_delay_usecs);
+ of_property_read_u16(node, "ti,penirq-recheck-delay-usecs",
+ &pdata->penirq_recheck_delay_usecs);
+
+ of_property_read_u16(node, "ti,x-plate-ohms", &pdata->x_plate_ohms);
+ of_property_read_u16(node, "ti,y-plate-ohms", &pdata->y_plate_ohms);
+
+ of_property_read_u16(node, "ti,x-min", &pdata->x_min);
+ of_property_read_u16(node, "ti,y-min", &pdata->y_min);
+ of_property_read_u16(node, "ti,x-max", &pdata->x_max);
+ of_property_read_u16(node, "ti,y-max", &pdata->y_max);
+
+ of_property_read_u16(node, "ti,pressure-min", &pdata->pressure_min);
+ of_property_read_u16(node, "ti,pressure-max", &pdata->pressure_max);
+
+ of_property_read_u16(node, "ti,debounce-max", &pdata->debounce_max);
+ of_property_read_u16(node, "ti,debounce-tol", &pdata->debounce_tol);
+ of_property_read_u16(node, "ti,debounce-rep", &pdata->debounce_rep);
+
+ of_property_read_u32(node, "ti,pendown-gpio-debounce",
+ &pdata->gpio_pendown_debounce);
+
+ pdata->wakeup = of_property_read_bool(node, "wakeup-source") ||
+ of_property_read_bool(node, "linux,wakeup");
+
+ pdata->gpio_pendown = of_get_named_gpio(dev->of_node, "pendown-gpio", 0);
+
+ return pdata;
+}
+#else
+static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev)
+{
+ dev_err(dev, "no platform data defined\n");
+ return ERR_PTR(-EINVAL);
+}
+#endif
+
+static int ads7846_probe(struct spi_device *spi)
+{
+ const struct ads7846_platform_data *pdata;
+ struct ads7846 *ts;
+ struct ads7846_packet *packet;
+ struct input_dev *input_dev;
+ unsigned long irq_flags;
+ int err;
+
+ if (!spi->irq) {
+ dev_dbg(&spi->dev, "no IRQ?\n");
+ return -EINVAL;
+ }
+
+ /* don't exceed max specified sample rate */
+ if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) {
+ dev_err(&spi->dev, "f(sample) %d KHz?\n",
+ (spi->max_speed_hz/SAMPLE_BITS)/1000);
+ return -EINVAL;
+ }
+
+ /*
+ * We'd set TX word size 8 bits and RX word size to 13 bits ... except
+ * that even if the hardware can do that, the SPI controller driver
+ * may not. So we stick to very-portable 8 bit words, both RX and TX.
+ */
+ spi->bits_per_word = 8;
+ spi->mode = SPI_MODE_0;
+ err = spi_setup(spi);
+ if (err < 0)
+ return err;
+
+ ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL);
+ packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL);
+ input_dev = input_allocate_device();
+ if (!ts || !packet || !input_dev) {
+ err = -ENOMEM;
+ goto err_free_mem;
+ }
+
+ spi_set_drvdata(spi, ts);
+
+ ts->packet = packet;
+ ts->spi = spi;
+ ts->input = input_dev;
+
+ mutex_init(&ts->lock);
+ init_waitqueue_head(&ts->wait);
+
+ pdata = dev_get_platdata(&spi->dev);
+ if (!pdata) {
+ pdata = ads7846_probe_dt(&spi->dev);
+ if (IS_ERR(pdata)) {
+ err = PTR_ERR(pdata);
+ goto err_free_mem;
+ }
+ }
+
+ ts->model = pdata->model ? : 7846;
+ ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100;
+ ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
+ ts->pressure_max = pdata->pressure_max ? : ~0;
+
+ ts->vref_mv = pdata->vref_mv;
+ ts->swap_xy = pdata->swap_xy;
+
+ if (pdata->filter != NULL) {
+ if (pdata->filter_init != NULL) {
+ err = pdata->filter_init(pdata, &ts->filter_data);
+ if (err < 0)
+ goto err_free_mem;
+ }
+ ts->filter = pdata->filter;
+ ts->filter_cleanup = pdata->filter_cleanup;
+ } else if (pdata->debounce_max) {
+ ts->debounce_max = pdata->debounce_max;
+ if (ts->debounce_max < 2)
+ ts->debounce_max = 2;
+ ts->debounce_tol = pdata->debounce_tol;
+ ts->debounce_rep = pdata->debounce_rep;
+ ts->filter = ads7846_debounce_filter;
+ ts->filter_data = ts;
+ } else {
+ ts->filter = ads7846_no_filter;
+ }
+
+ err = ads7846_setup_pendown(spi, ts, pdata);
+ if (err)
+ goto err_cleanup_filter;
+
+ if (pdata->penirq_recheck_delay_usecs)
+ ts->penirq_recheck_delay_usecs =
+ pdata->penirq_recheck_delay_usecs;
+
+ ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync;
+
+ snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev));
+ snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model);
+
+ input_dev->name = ts->name;
+ input_dev->phys = ts->phys;
+ input_dev->dev.parent = &spi->dev;
+
+ input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+ input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+ input_set_abs_params(input_dev, ABS_X,
+ pdata->x_min ? : 0,
+ pdata->x_max ? : MAX_12BIT,
+ 0, 0);
+ input_set_abs_params(input_dev, ABS_Y,
+ pdata->y_min ? : 0,
+ pdata->y_max ? : MAX_12BIT,
+ 0, 0);
+ input_set_abs_params(input_dev, ABS_PRESSURE,
+ pdata->pressure_min, pdata->pressure_max, 0, 0);
+
+ ads7846_setup_spi_msg(ts, pdata);
+
+ ts->reg = regulator_get(&spi->dev, "vcc");
+ if (IS_ERR(ts->reg)) {
+ err = PTR_ERR(ts->reg);
+ dev_err(&spi->dev, "unable to get regulator: %d\n", err);
+ goto err_free_gpio;
+ }
+
+ err = regulator_enable(ts->reg);
+ if (err) {
+ dev_err(&spi->dev, "unable to enable regulator: %d\n", err);
+ goto err_put_regulator;
+ }
+
+ irq_flags = pdata->irq_flags ? : IRQF_TRIGGER_FALLING;
+ irq_flags |= IRQF_ONESHOT;
+
+ err = request_threaded_irq(spi->irq, ads7846_hard_irq, ads7846_irq,
+ irq_flags, spi->dev.driver->name, ts);
+ if (err && !pdata->irq_flags) {
+ dev_info(&spi->dev,
+ "trying pin change workaround on irq %d\n", spi->irq);
+ irq_flags |= IRQF_TRIGGER_RISING;
+ err = request_threaded_irq(spi->irq,
+ ads7846_hard_irq, ads7846_irq,
+ irq_flags, spi->dev.driver->name, ts);
+ }
+
+ if (err) {
+ dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq);
+ goto err_disable_regulator;
+ }
+
+ err = ads784x_hwmon_register(spi, ts);
+ if (err)
+ goto err_free_irq;
+
+ dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq);
+
+ /*
+ * Take a first sample, leaving nPENIRQ active and vREF off; avoid
+ * the touchscreen, in case it's not connected.
+ */
+ if (ts->model == 7845)
+ ads7845_read12_ser(&spi->dev, PWRDOWN);
+ else
+ (void) ads7846_read12_ser(&spi->dev, READ_12BIT_SER(vaux));
+
+ err = sysfs_create_group(&spi->dev.kobj, &ads784x_attr_group);
+ if (err)
+ goto err_remove_hwmon;
+
+ err = input_register_device(input_dev);
+ if (err)
+ goto err_remove_attr_group;
+
+ device_init_wakeup(&spi->dev, pdata->wakeup);
+
+ /*
+ * If device does not carry platform data we must have allocated it
+ * when parsing DT data.
+ */
+ if (!dev_get_platdata(&spi->dev))
+ devm_kfree(&spi->dev, (void *)pdata);
+
+ return 0;
+
+ err_remove_attr_group:
+ sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group);
+ err_remove_hwmon:
+ ads784x_hwmon_unregister(spi, ts);
+ err_free_irq:
+ free_irq(spi->irq, ts);
+ err_disable_regulator:
+ regulator_disable(ts->reg);
+ err_put_regulator:
+ regulator_put(ts->reg);
+ err_free_gpio:
+ if (!ts->get_pendown_state)
+ gpio_free(ts->gpio_pendown);
+ err_cleanup_filter:
+ if (ts->filter_cleanup)
+ ts->filter_cleanup(ts->filter_data);
+ err_free_mem:
+ input_free_device(input_dev);
+ kfree(packet);
+ kfree(ts);
+ return err;
+}
+
+static int ads7846_remove(struct spi_device *spi)
+{
+ struct ads7846 *ts = spi_get_drvdata(spi);
+
+ sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group);
+
+ ads7846_disable(ts);
+ free_irq(ts->spi->irq, ts);
+
+ input_unregister_device(ts->input);
+
+ ads784x_hwmon_unregister(spi, ts);
+
+ regulator_put(ts->reg);
+
+ if (!ts->get_pendown_state) {
+ /*
+ * If we are not using specialized pendown method we must
+ * have been relying on gpio we set up ourselves.
+ */
+ gpio_free(ts->gpio_pendown);
+ }
+
+ if (ts->filter_cleanup)
+ ts->filter_cleanup(ts->filter_data);
+
+ kfree(ts->packet);
+ kfree(ts);
+
+ dev_dbg(&spi->dev, "unregistered touchscreen\n");
+
+ return 0;
+}
+
+static struct spi_driver ads7846_driver = {
+ .driver = {
+ .name = "ads7846",
+ .pm = &ads7846_pm,
+ .of_match_table = of_match_ptr(ads7846_dt_ids),
+ },
+ .probe = ads7846_probe,
+ .remove = ads7846_remove,
+};
+
+module_spi_driver(ads7846_driver);
+
+MODULE_DESCRIPTION("ADS7846 TouchScreen Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:ads7846");