[Feature]add MT2731_MP2_MR2_SVN388 baseline version

Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/sound/usb/line6/driver.c b/src/kernel/linux/v4.14/sound/usb/line6/driver.c
new file mode 100644
index 0000000..bf4eacc
--- /dev/null
+++ b/src/kernel/linux/v4.14/sound/usb/line6/driver.c
@@ -0,0 +1,884 @@
+/*
+ * Line 6 Linux USB driver
+ *
+ * Copyright (C) 2004-2010 Markus Grabner (grabner@icg.tugraz.at)
+ *
+ *	This program is free software; you can redistribute it and/or
+ *	modify it under the terms of the GNU General Public License as
+ *	published by the Free Software Foundation, version 2.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+
+#include <sound/core.h>
+#include <sound/initval.h>
+#include <sound/hwdep.h>
+
+#include "capture.h"
+#include "driver.h"
+#include "midi.h"
+#include "playback.h"
+
+#define DRIVER_AUTHOR  "Markus Grabner <grabner@icg.tugraz.at>"
+#define DRIVER_DESC    "Line 6 USB Driver"
+
+/*
+	This is Line 6's MIDI manufacturer ID.
+*/
+const unsigned char line6_midi_id[3] = {
+	0x00, 0x01, 0x0c
+};
+EXPORT_SYMBOL_GPL(line6_midi_id);
+
+/*
+	Code to request version of POD, Variax interface
+	(and maybe other devices).
+*/
+static const char line6_request_version[] = {
+	0xf0, 0x7e, 0x7f, 0x06, 0x01, 0xf7
+};
+
+/*
+	 Class for asynchronous messages.
+*/
+struct message {
+	struct usb_line6 *line6;
+	const char *buffer;
+	int size;
+	int done;
+};
+
+/*
+	Forward declarations.
+*/
+static void line6_data_received(struct urb *urb);
+static int line6_send_raw_message_async_part(struct message *msg,
+					     struct urb *urb);
+
+/*
+	Start to listen on endpoint.
+*/
+static int line6_start_listen(struct usb_line6 *line6)
+{
+	int err;
+
+	if (line6->properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
+		usb_fill_int_urb(line6->urb_listen, line6->usbdev,
+			usb_rcvintpipe(line6->usbdev, line6->properties->ep_ctrl_r),
+			line6->buffer_listen, LINE6_BUFSIZE_LISTEN,
+			line6_data_received, line6, line6->interval);
+	} else {
+		usb_fill_bulk_urb(line6->urb_listen, line6->usbdev,
+			usb_rcvbulkpipe(line6->usbdev, line6->properties->ep_ctrl_r),
+			line6->buffer_listen, LINE6_BUFSIZE_LISTEN,
+			line6_data_received, line6);
+	}
+
+	/* sanity checks of EP before actually submitting */
+	if (usb_urb_ep_type_check(line6->urb_listen)) {
+		dev_err(line6->ifcdev, "invalid control EP\n");
+		return -EINVAL;
+	}
+
+	line6->urb_listen->actual_length = 0;
+	err = usb_submit_urb(line6->urb_listen, GFP_ATOMIC);
+	return err;
+}
+
+/*
+	Stop listening on endpoint.
+*/
+static void line6_stop_listen(struct usb_line6 *line6)
+{
+	usb_kill_urb(line6->urb_listen);
+}
+
+/*
+	Send raw message in pieces of wMaxPacketSize bytes.
+*/
+static int line6_send_raw_message(struct usb_line6 *line6, const char *buffer,
+				  int size)
+{
+	int i, done = 0;
+	const struct line6_properties *properties = line6->properties;
+
+	for (i = 0; i < size; i += line6->max_packet_size) {
+		int partial;
+		const char *frag_buf = buffer + i;
+		int frag_size = min(line6->max_packet_size, size - i);
+		int retval;
+
+		if (properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
+			retval = usb_interrupt_msg(line6->usbdev,
+						usb_sndintpipe(line6->usbdev, properties->ep_ctrl_w),
+						(char *)frag_buf, frag_size,
+						&partial, LINE6_TIMEOUT * HZ);
+		} else {
+			retval = usb_bulk_msg(line6->usbdev,
+						usb_sndbulkpipe(line6->usbdev, properties->ep_ctrl_w),
+						(char *)frag_buf, frag_size,
+						&partial, LINE6_TIMEOUT * HZ);
+		}
+
+		if (retval) {
+			dev_err(line6->ifcdev,
+				"usb_bulk_msg failed (%d)\n", retval);
+			break;
+		}
+
+		done += frag_size;
+	}
+
+	return done;
+}
+
+/*
+	Notification of completion of asynchronous request transmission.
+*/
+static void line6_async_request_sent(struct urb *urb)
+{
+	struct message *msg = (struct message *)urb->context;
+
+	if (msg->done >= msg->size) {
+		usb_free_urb(urb);
+		kfree(msg);
+	} else
+		line6_send_raw_message_async_part(msg, urb);
+}
+
+/*
+	Asynchronously send part of a raw message.
+*/
+static int line6_send_raw_message_async_part(struct message *msg,
+					     struct urb *urb)
+{
+	int retval;
+	struct usb_line6 *line6 = msg->line6;
+	int done = msg->done;
+	int bytes = min(msg->size - done, line6->max_packet_size);
+
+	if (line6->properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
+		usb_fill_int_urb(urb, line6->usbdev,
+			usb_sndintpipe(line6->usbdev, line6->properties->ep_ctrl_w),
+			(char *)msg->buffer + done, bytes,
+			line6_async_request_sent, msg, line6->interval);
+	} else {
+		usb_fill_bulk_urb(urb, line6->usbdev,
+			usb_sndbulkpipe(line6->usbdev, line6->properties->ep_ctrl_w),
+			(char *)msg->buffer + done, bytes,
+			line6_async_request_sent, msg);
+	}
+
+	msg->done += bytes;
+	retval = usb_submit_urb(urb, GFP_ATOMIC);
+
+	if (retval < 0) {
+		dev_err(line6->ifcdev, "%s: usb_submit_urb failed (%d)\n",
+			__func__, retval);
+		usb_free_urb(urb);
+		kfree(msg);
+		return retval;
+	}
+
+	return 0;
+}
+
+/*
+	Setup and start timer.
+*/
+void line6_start_timer(struct timer_list *timer, unsigned long msecs,
+		       void (*function)(unsigned long), unsigned long data)
+{
+	setup_timer(timer, function, data);
+	mod_timer(timer, jiffies + msecs_to_jiffies(msecs));
+}
+EXPORT_SYMBOL_GPL(line6_start_timer);
+
+/*
+	Asynchronously send raw message.
+*/
+int line6_send_raw_message_async(struct usb_line6 *line6, const char *buffer,
+				 int size)
+{
+	struct message *msg;
+	struct urb *urb;
+
+	/* create message: */
+	msg = kmalloc(sizeof(struct message), GFP_ATOMIC);
+	if (msg == NULL)
+		return -ENOMEM;
+
+	/* create URB: */
+	urb = usb_alloc_urb(0, GFP_ATOMIC);
+
+	if (urb == NULL) {
+		kfree(msg);
+		return -ENOMEM;
+	}
+
+	/* set message data: */
+	msg->line6 = line6;
+	msg->buffer = buffer;
+	msg->size = size;
+	msg->done = 0;
+
+	/* start sending: */
+	return line6_send_raw_message_async_part(msg, urb);
+}
+EXPORT_SYMBOL_GPL(line6_send_raw_message_async);
+
+/*
+	Send asynchronous device version request.
+*/
+int line6_version_request_async(struct usb_line6 *line6)
+{
+	char *buffer;
+	int retval;
+
+	buffer = kmemdup(line6_request_version,
+			sizeof(line6_request_version), GFP_ATOMIC);
+	if (buffer == NULL)
+		return -ENOMEM;
+
+	retval = line6_send_raw_message_async(line6, buffer,
+					      sizeof(line6_request_version));
+	kfree(buffer);
+	return retval;
+}
+EXPORT_SYMBOL_GPL(line6_version_request_async);
+
+/*
+	Send sysex message in pieces of wMaxPacketSize bytes.
+*/
+int line6_send_sysex_message(struct usb_line6 *line6, const char *buffer,
+			     int size)
+{
+	return line6_send_raw_message(line6, buffer,
+				      size + SYSEX_EXTRA_SIZE) -
+	    SYSEX_EXTRA_SIZE;
+}
+EXPORT_SYMBOL_GPL(line6_send_sysex_message);
+
+/*
+	Allocate buffer for sysex message and prepare header.
+	@param code sysex message code
+	@param size number of bytes between code and sysex end
+*/
+char *line6_alloc_sysex_buffer(struct usb_line6 *line6, int code1, int code2,
+			       int size)
+{
+	char *buffer = kmalloc(size + SYSEX_EXTRA_SIZE, GFP_ATOMIC);
+
+	if (!buffer)
+		return NULL;
+
+	buffer[0] = LINE6_SYSEX_BEGIN;
+	memcpy(buffer + 1, line6_midi_id, sizeof(line6_midi_id));
+	buffer[sizeof(line6_midi_id) + 1] = code1;
+	buffer[sizeof(line6_midi_id) + 2] = code2;
+	buffer[sizeof(line6_midi_id) + 3 + size] = LINE6_SYSEX_END;
+	return buffer;
+}
+EXPORT_SYMBOL_GPL(line6_alloc_sysex_buffer);
+
+/*
+	Notification of data received from the Line 6 device.
+*/
+static void line6_data_received(struct urb *urb)
+{
+	struct usb_line6 *line6 = (struct usb_line6 *)urb->context;
+	struct midi_buffer *mb = &line6->line6midi->midibuf_in;
+	int done;
+
+	if (urb->status == -ESHUTDOWN)
+		return;
+
+	if (line6->properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
+		done =
+			line6_midibuf_write(mb, urb->transfer_buffer, urb->actual_length);
+
+		if (done < urb->actual_length) {
+			line6_midibuf_ignore(mb, done);
+			dev_dbg(line6->ifcdev, "%d %d buffer overflow - message skipped\n",
+				done, urb->actual_length);
+		}
+
+		for (;;) {
+			done =
+				line6_midibuf_read(mb, line6->buffer_message,
+						LINE6_MIDI_MESSAGE_MAXLEN);
+
+			if (done <= 0)
+				break;
+
+			line6->message_length = done;
+			line6_midi_receive(line6, line6->buffer_message, done);
+
+			if (line6->process_message)
+				line6->process_message(line6);
+		}
+	} else {
+		line6->buffer_message = urb->transfer_buffer;
+		line6->message_length = urb->actual_length;
+		if (line6->process_message)
+			line6->process_message(line6);
+		line6->buffer_message = NULL;
+	}
+
+	line6_start_listen(line6);
+}
+
+#define LINE6_READ_WRITE_STATUS_DELAY 2  /* milliseconds */
+#define LINE6_READ_WRITE_MAX_RETRIES 50
+
+/*
+	Read data from device.
+*/
+int line6_read_data(struct usb_line6 *line6, unsigned address, void *data,
+		    unsigned datalen)
+{
+	struct usb_device *usbdev = line6->usbdev;
+	int ret;
+	unsigned char *len;
+	unsigned count;
+
+	if (address > 0xffff || datalen > 0xff)
+		return -EINVAL;
+
+	len = kmalloc(sizeof(*len), GFP_KERNEL);
+	if (!len)
+		return -ENOMEM;
+
+	/* query the serial number: */
+	ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0), 0x67,
+			      USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
+			      (datalen << 8) | 0x21, address,
+			      NULL, 0, LINE6_TIMEOUT * HZ);
+
+	if (ret < 0) {
+		dev_err(line6->ifcdev, "read request failed (error %d)\n", ret);
+		goto exit;
+	}
+
+	/* Wait for data length. We'll get 0xff until length arrives. */
+	for (count = 0; count < LINE6_READ_WRITE_MAX_RETRIES; count++) {
+		mdelay(LINE6_READ_WRITE_STATUS_DELAY);
+
+		ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0), 0x67,
+				      USB_TYPE_VENDOR | USB_RECIP_DEVICE |
+				      USB_DIR_IN,
+				      0x0012, 0x0000, len, 1,
+				      LINE6_TIMEOUT * HZ);
+		if (ret < 0) {
+			dev_err(line6->ifcdev,
+				"receive length failed (error %d)\n", ret);
+			goto exit;
+		}
+
+		if (*len != 0xff)
+			break;
+	}
+
+	ret = -EIO;
+	if (*len == 0xff) {
+		dev_err(line6->ifcdev, "read failed after %d retries\n",
+			count);
+		goto exit;
+	} else if (*len != datalen) {
+		/* should be equal or something went wrong */
+		dev_err(line6->ifcdev,
+			"length mismatch (expected %d, got %d)\n",
+			(int)datalen, (int)*len);
+		goto exit;
+	}
+
+	/* receive the result: */
+	ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0), 0x67,
+			      USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
+			      0x0013, 0x0000, data, datalen,
+			      LINE6_TIMEOUT * HZ);
+
+	if (ret < 0)
+		dev_err(line6->ifcdev, "read failed (error %d)\n", ret);
+
+exit:
+	kfree(len);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(line6_read_data);
+
+/*
+	Write data to device.
+*/
+int line6_write_data(struct usb_line6 *line6, unsigned address, void *data,
+		     unsigned datalen)
+{
+	struct usb_device *usbdev = line6->usbdev;
+	int ret;
+	unsigned char *status;
+	int count;
+
+	if (address > 0xffff || datalen > 0xffff)
+		return -EINVAL;
+
+	status = kmalloc(sizeof(*status), GFP_KERNEL);
+	if (!status)
+		return -ENOMEM;
+
+	ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0), 0x67,
+			      USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
+			      0x0022, address, data, datalen,
+			      LINE6_TIMEOUT * HZ);
+
+	if (ret < 0) {
+		dev_err(line6->ifcdev,
+			"write request failed (error %d)\n", ret);
+		goto exit;
+	}
+
+	for (count = 0; count < LINE6_READ_WRITE_MAX_RETRIES; count++) {
+		mdelay(LINE6_READ_WRITE_STATUS_DELAY);
+
+		ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0),
+				      0x67,
+				      USB_TYPE_VENDOR | USB_RECIP_DEVICE |
+				      USB_DIR_IN,
+				      0x0012, 0x0000,
+				      status, 1, LINE6_TIMEOUT * HZ);
+
+		if (ret < 0) {
+			dev_err(line6->ifcdev,
+				"receiving status failed (error %d)\n", ret);
+			goto exit;
+		}
+
+		if (*status != 0xff)
+			break;
+	}
+
+	if (*status == 0xff) {
+		dev_err(line6->ifcdev, "write failed after %d retries\n",
+			count);
+		ret = -EIO;
+	} else if (*status != 0) {
+		dev_err(line6->ifcdev, "write failed (error %d)\n", ret);
+		ret = -EIO;
+	}
+exit:
+	kfree(status);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(line6_write_data);
+
+/*
+	Read Line 6 device serial number.
+	(POD, TonePort, GuitarPort)
+*/
+int line6_read_serial_number(struct usb_line6 *line6, u32 *serial_number)
+{
+	return line6_read_data(line6, 0x80d0, serial_number,
+			       sizeof(*serial_number));
+}
+EXPORT_SYMBOL_GPL(line6_read_serial_number);
+
+/*
+	Card destructor.
+*/
+static void line6_destruct(struct snd_card *card)
+{
+	struct usb_line6 *line6 = card->private_data;
+	struct usb_device *usbdev = line6->usbdev;
+
+	/* Free buffer memory first. We cannot depend on the existence of private
+	 * data from the (podhd) module, it may be gone already during this call
+	 */
+	kfree(line6->buffer_message);
+
+	kfree(line6->buffer_listen);
+
+	/* then free URBs: */
+	usb_free_urb(line6->urb_listen);
+	line6->urb_listen = NULL;
+
+	/* decrement reference counters: */
+	usb_put_dev(usbdev);
+}
+
+static void line6_get_usb_properties(struct usb_line6 *line6)
+{
+	struct usb_device *usbdev = line6->usbdev;
+	const struct line6_properties *properties = line6->properties;
+	int pipe;
+	struct usb_host_endpoint *ep = NULL;
+
+	if (properties->capabilities & LINE6_CAP_CONTROL) {
+		if (properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
+			pipe = usb_rcvintpipe(line6->usbdev,
+				line6->properties->ep_ctrl_r);
+		} else {
+			pipe = usb_rcvbulkpipe(line6->usbdev,
+				line6->properties->ep_ctrl_r);
+		}
+		ep = usbdev->ep_in[usb_pipeendpoint(pipe)];
+	}
+
+	/* Control data transfer properties */
+	if (ep) {
+		line6->interval = ep->desc.bInterval;
+		line6->max_packet_size = le16_to_cpu(ep->desc.wMaxPacketSize);
+	} else {
+		if (properties->capabilities & LINE6_CAP_CONTROL) {
+			dev_err(line6->ifcdev,
+				"endpoint not available, using fallback values");
+		}
+		line6->interval = LINE6_FALLBACK_INTERVAL;
+		line6->max_packet_size = LINE6_FALLBACK_MAXPACKETSIZE;
+	}
+
+	/* Isochronous transfer properties */
+	if (usbdev->speed == USB_SPEED_LOW) {
+		line6->intervals_per_second = USB_LOW_INTERVALS_PER_SECOND;
+		line6->iso_buffers = USB_LOW_ISO_BUFFERS;
+	} else {
+		line6->intervals_per_second = USB_HIGH_INTERVALS_PER_SECOND;
+		line6->iso_buffers = USB_HIGH_ISO_BUFFERS;
+	}
+}
+
+/* Enable buffering of incoming messages, flush the buffer */
+static int line6_hwdep_open(struct snd_hwdep *hw, struct file *file)
+{
+	struct usb_line6 *line6 = hw->private_data;
+
+	/* NOTE: hwdep layer provides atomicity here */
+
+	line6->messages.active = 1;
+
+	return 0;
+}
+
+/* Stop buffering */
+static int line6_hwdep_release(struct snd_hwdep *hw, struct file *file)
+{
+	struct usb_line6 *line6 = hw->private_data;
+
+	line6->messages.active = 0;
+
+	return 0;
+}
+
+/* Read from circular buffer, return to user */
+static long
+line6_hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count,
+					loff_t *offset)
+{
+	struct usb_line6 *line6 = hwdep->private_data;
+	long rv = 0;
+	unsigned int out_count;
+
+	if (mutex_lock_interruptible(&line6->messages.read_lock))
+		return -ERESTARTSYS;
+
+	while (kfifo_len(&line6->messages.fifo) == 0) {
+		mutex_unlock(&line6->messages.read_lock);
+
+		rv = wait_event_interruptible(
+			line6->messages.wait_queue,
+			kfifo_len(&line6->messages.fifo) != 0);
+		if (rv < 0)
+			return rv;
+
+		if (mutex_lock_interruptible(&line6->messages.read_lock))
+			return -ERESTARTSYS;
+	}
+
+	if (kfifo_peek_len(&line6->messages.fifo) > count) {
+		/* Buffer too small; allow re-read of the current item... */
+		rv = -EINVAL;
+	} else {
+		rv = kfifo_to_user(&line6->messages.fifo, buf, count, &out_count);
+		if (rv == 0)
+			rv = out_count;
+	}
+
+	mutex_unlock(&line6->messages.read_lock);
+	return rv;
+}
+
+/* Write directly (no buffering) to device by user*/
+static long
+line6_hwdep_write(struct snd_hwdep *hwdep, const char __user *data, long count,
+					loff_t *offset)
+{
+	struct usb_line6 *line6 = hwdep->private_data;
+	int rv;
+	char *data_copy;
+
+	if (count > line6->max_packet_size * LINE6_RAW_MESSAGES_MAXCOUNT) {
+		/* This is an arbitrary limit - still better than nothing... */
+		return -EINVAL;
+	}
+
+	data_copy = memdup_user(data, count);
+	if (IS_ERR(data_copy))
+		return PTR_ERR(data_copy);
+
+	rv = line6_send_raw_message(line6, data_copy, count);
+
+	kfree(data_copy);
+	return rv;
+}
+
+static const struct snd_hwdep_ops hwdep_ops = {
+	.open    = line6_hwdep_open,
+	.release = line6_hwdep_release,
+	.read    = line6_hwdep_read,
+	.write   = line6_hwdep_write,
+};
+
+/* Insert into circular buffer */
+static void line6_hwdep_push_message(struct usb_line6 *line6)
+{
+	if (!line6->messages.active)
+		return;
+
+	if (kfifo_avail(&line6->messages.fifo) >= line6->message_length) {
+		/* No race condition here, there's only one writer */
+		kfifo_in(&line6->messages.fifo,
+			line6->buffer_message, line6->message_length);
+	} /* else TODO: signal overflow */
+
+	wake_up_interruptible(&line6->messages.wait_queue);
+}
+
+static int line6_hwdep_init(struct usb_line6 *line6)
+{
+	int err;
+	struct snd_hwdep *hwdep;
+
+	/* TODO: usb_driver_claim_interface(); */
+	line6->process_message = line6_hwdep_push_message;
+	line6->messages.active = 0;
+	init_waitqueue_head(&line6->messages.wait_queue);
+	mutex_init(&line6->messages.read_lock);
+	INIT_KFIFO(line6->messages.fifo);
+
+	err = snd_hwdep_new(line6->card, "config", 0, &hwdep);
+	if (err < 0)
+		goto end;
+	strcpy(hwdep->name, "config");
+	hwdep->iface = SNDRV_HWDEP_IFACE_LINE6;
+	hwdep->ops = hwdep_ops;
+	hwdep->private_data = line6;
+	hwdep->exclusive = true;
+
+end:
+	return err;
+}
+
+static int line6_init_cap_control(struct usb_line6 *line6)
+{
+	int ret;
+
+	/* initialize USB buffers: */
+	line6->buffer_listen = kmalloc(LINE6_BUFSIZE_LISTEN, GFP_KERNEL);
+	if (!line6->buffer_listen)
+		return -ENOMEM;
+
+	line6->urb_listen = usb_alloc_urb(0, GFP_KERNEL);
+	if (!line6->urb_listen)
+		return -ENOMEM;
+
+	if (line6->properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
+		line6->buffer_message = kmalloc(LINE6_MIDI_MESSAGE_MAXLEN, GFP_KERNEL);
+		if (!line6->buffer_message)
+			return -ENOMEM;
+	} else {
+		ret = line6_hwdep_init(line6);
+		if (ret < 0)
+			return ret;
+	}
+
+	ret = line6_start_listen(line6);
+	if (ret < 0) {
+		dev_err(line6->ifcdev, "cannot start listening: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+/*
+	Probe USB device.
+*/
+int line6_probe(struct usb_interface *interface,
+		const struct usb_device_id *id,
+		const char *driver_name,
+		const struct line6_properties *properties,
+		int (*private_init)(struct usb_line6 *, const struct usb_device_id *id),
+		size_t data_size)
+{
+	struct usb_device *usbdev = interface_to_usbdev(interface);
+	struct snd_card *card;
+	struct usb_line6 *line6;
+	int interface_number;
+	int ret;
+
+	if (WARN_ON(data_size < sizeof(*line6)))
+		return -EINVAL;
+
+	/* we don't handle multiple configurations */
+	if (usbdev->descriptor.bNumConfigurations != 1)
+		return -ENODEV;
+
+	ret = snd_card_new(&interface->dev,
+			   SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
+			   THIS_MODULE, data_size, &card);
+	if (ret < 0)
+		return ret;
+
+	/* store basic data: */
+	line6 = card->private_data;
+	line6->card = card;
+	line6->properties = properties;
+	line6->usbdev = usbdev;
+	line6->ifcdev = &interface->dev;
+
+	strcpy(card->id, properties->id);
+	strcpy(card->driver, driver_name);
+	strcpy(card->shortname, properties->name);
+	sprintf(card->longname, "Line 6 %s at USB %s", properties->name,
+		dev_name(line6->ifcdev));
+	card->private_free = line6_destruct;
+
+	usb_set_intfdata(interface, line6);
+
+	/* increment reference counters: */
+	usb_get_dev(usbdev);
+
+	/* initialize device info: */
+	dev_info(&interface->dev, "Line 6 %s found\n", properties->name);
+
+	/* query interface number */
+	interface_number = interface->cur_altsetting->desc.bInterfaceNumber;
+
+	/* TODO reserves the bus bandwidth even without actual transfer */
+	ret = usb_set_interface(usbdev, interface_number,
+				properties->altsetting);
+	if (ret < 0) {
+		dev_err(&interface->dev, "set_interface failed\n");
+		goto error;
+	}
+
+	line6_get_usb_properties(line6);
+
+	if (properties->capabilities & LINE6_CAP_CONTROL) {
+		ret = line6_init_cap_control(line6);
+		if (ret < 0)
+			goto error;
+	}
+
+	/* initialize device data based on device: */
+	ret = private_init(line6, id);
+	if (ret < 0)
+		goto error;
+
+	/* creation of additional special files should go here */
+
+	dev_info(&interface->dev, "Line 6 %s now attached\n",
+		 properties->name);
+
+	return 0;
+
+ error:
+	/* we can call disconnect callback here because no close-sync is
+	 * needed yet at this point
+	 */
+	line6_disconnect(interface);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(line6_probe);
+
+/*
+	Line 6 device disconnected.
+*/
+void line6_disconnect(struct usb_interface *interface)
+{
+	struct usb_line6 *line6 = usb_get_intfdata(interface);
+	struct usb_device *usbdev = interface_to_usbdev(interface);
+
+	if (!line6)
+		return;
+
+	if (WARN_ON(usbdev != line6->usbdev))
+		return;
+
+	if (line6->urb_listen != NULL)
+		line6_stop_listen(line6);
+
+	snd_card_disconnect(line6->card);
+	if (line6->line6pcm)
+		line6_pcm_disconnect(line6->line6pcm);
+	if (line6->disconnect)
+		line6->disconnect(line6);
+
+	dev_info(&interface->dev, "Line 6 %s now disconnected\n",
+		 line6->properties->name);
+
+	/* make sure the device isn't destructed twice: */
+	usb_set_intfdata(interface, NULL);
+
+	snd_card_free_when_closed(line6->card);
+}
+EXPORT_SYMBOL_GPL(line6_disconnect);
+
+#ifdef CONFIG_PM
+
+/*
+	Suspend Line 6 device.
+*/
+int line6_suspend(struct usb_interface *interface, pm_message_t message)
+{
+	struct usb_line6 *line6 = usb_get_intfdata(interface);
+	struct snd_line6_pcm *line6pcm = line6->line6pcm;
+
+	snd_power_change_state(line6->card, SNDRV_CTL_POWER_D3hot);
+
+	if (line6->properties->capabilities & LINE6_CAP_CONTROL)
+		line6_stop_listen(line6);
+
+	if (line6pcm != NULL) {
+		snd_pcm_suspend_all(line6pcm->pcm);
+		line6pcm->flags = 0;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(line6_suspend);
+
+/*
+	Resume Line 6 device.
+*/
+int line6_resume(struct usb_interface *interface)
+{
+	struct usb_line6 *line6 = usb_get_intfdata(interface);
+
+	if (line6->properties->capabilities & LINE6_CAP_CONTROL)
+		line6_start_listen(line6);
+
+	snd_power_change_state(line6->card, SNDRV_CTL_POWER_D0);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(line6_resume);
+
+#endif /* CONFIG_PM */
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+