drivers/staging/line6/midi.c - kernel/skids - Git at Google

 /*
  * Line6 Linux USB driver - 0.8.0
  *
  * Copyright (C) 2004-2009 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 "driver.h"

 #include <linux/usb.h>
 #include <linux/slab.h>

 #include <sound/core.h>
 #include <sound/rawmidi.h>

 #include "audio.h"
 #include "midi.h"
 #include "pod.h"
 #include "usbdefs.h"


 #define USE_MIDIBUF      1
 #define OUTPUT_DUMP_ONLY 0


 #define line6_rawmidi_substream_midi(substream) \
 	((struct snd_line6_midi *)((substream)->rmidi->private_data))


 static int send_midi_async(struct usb_line6 *line6, unsigned char *data,
 			   int length);


 /*
 	Pass data received via USB to MIDI.
 */
 void line6_midi_receive(struct usb_line6 *line6, unsigned char *data,
 			int length)
 {
 	if (line6->line6midi->substream_receive)
 		snd_rawmidi_receive(line6->line6midi->substream_receive,
 				    data, length);
 }

 /*
 	Read data from MIDI buffer and transmit them via USB.
 */
 static void line6_midi_transmit(struct snd_rawmidi_substream *substream)
 {
 	struct usb_line6 *line6 = line6_rawmidi_substream_midi(substream)->line6;
 	struct snd_line6_midi *line6midi = line6->line6midi;
 	struct MidiBuffer *mb = &line6midi->midibuf_out;
 	unsigned long flags;
 	unsigned char chunk[line6->max_packet_size];
 	int req, done;

 	spin_lock_irqsave(&line6->line6midi->midi_transmit_lock, flags);

 	for (;;) {
 		req = min(midibuf_bytes_free(mb), line6->max_packet_size);
 		done = snd_rawmidi_transmit_peek(substream, chunk, req);

 		if (done == 0)
 			break;

 #if DO_DUMP_MIDI_SEND
 		line6_write_hexdump(line6, 's', chunk, done);
 #endif
 		midibuf_write(mb, chunk, done);
 		snd_rawmidi_transmit_ack(substream, done);
 	}

 	for (;;) {
 		done = midibuf_read(mb, chunk, line6->max_packet_size);

 		if (done == 0)
 			break;

 		if (midibuf_skip_message(mb, line6midi->midi_mask_transmit))
 			continue;

 		send_midi_async(line6, chunk, done);
 	}

 	spin_unlock_irqrestore(&line6->line6midi->midi_transmit_lock, flags);
 }

 /*
 	Notification of completion of MIDI transmission.
 */
 static void midi_sent(struct urb *urb)
 {
 	unsigned long flags;
 	int status;
 	int num;
 	struct usb_line6 *line6 = (struct usb_line6 *)urb->context;

 	status = urb->status;
 	kfree(urb->transfer_buffer);
 	usb_free_urb(urb);

 	if (status == -ESHUTDOWN)
 		return;

 	spin_lock_irqsave(&line6->line6midi->send_urb_lock, flags);
 	num = --line6->line6midi->num_active_send_urbs;

 	if (num == 0) {
 		line6_midi_transmit(line6->line6midi->substream_transmit);
 		num = line6->line6midi->num_active_send_urbs;
 	}

 	if (num == 0)
 		wake_up_interruptible(&line6->line6midi->send_wait);

 	spin_unlock_irqrestore(&line6->line6midi->send_urb_lock, flags);
 }

 /*
 	Send an asynchronous MIDI message.
 	Assumes that line6->line6midi->send_urb_lock is held
 	(i.e., this function is serialized).
 */
 static int send_midi_async(struct usb_line6 *line6, unsigned char *data,
 			   int length)
 {
 	struct urb *urb;
 	int retval;
 	unsigned char *transfer_buffer;

 	urb = usb_alloc_urb(0, GFP_ATOMIC);

 	if (urb == 0) {
 		dev_err(line6->ifcdev, "Out of memory\n");
 		return -ENOMEM;
 	}

 #if DO_DUMP_URB_SEND
 	line6_write_hexdump(line6, 'S', data, length);
 #endif

 	transfer_buffer = kmalloc(length, GFP_ATOMIC);

 	if (transfer_buffer == 0) {
 		usb_free_urb(urb);
 		dev_err(line6->ifcdev, "Out of memory\n");
 		return -ENOMEM;
 	}

 	memcpy(transfer_buffer, data, length);
 	usb_fill_int_urb(urb, line6->usbdev,
 			 usb_sndbulkpipe(line6->usbdev,
 					 line6->ep_control_write),
 			 transfer_buffer, length, midi_sent, line6,
 			 line6->interval);
 	urb->actual_length = 0;
 	retval = usb_submit_urb(urb, GFP_ATOMIC);

 	if (retval < 0) {
 		dev_err(line6->ifcdev, "usb_submit_urb failed\n");
 		usb_free_urb(urb);
 		return -EINVAL;
 	}

 	++line6->line6midi->num_active_send_urbs;

 	switch (line6->usbdev->descriptor.idProduct) {
 	case LINE6_DEVID_BASSPODXT:
 	case LINE6_DEVID_BASSPODXTLIVE:
 	case LINE6_DEVID_BASSPODXTPRO:
 	case LINE6_DEVID_PODXT:
 	case LINE6_DEVID_PODXTLIVE:
 	case LINE6_DEVID_PODXTPRO:
 	case LINE6_DEVID_POCKETPOD:
 		pod_midi_postprocess((struct usb_line6_pod *)line6, data,
 				     length);
 		break;

 	default:
 		MISSING_CASE;
 	}

 	return 0;
 }

 static int line6_midi_output_open(struct snd_rawmidi_substream *substream)
 {
 	return 0;
 }

 static int line6_midi_output_close(struct snd_rawmidi_substream *substream)
 {
 	return 0;
 }

 static void line6_midi_output_trigger(struct snd_rawmidi_substream *substream,
 				      int up)
 {
 	unsigned long flags;
 	struct usb_line6 *line6 = line6_rawmidi_substream_midi(substream)->line6;

 	line6->line6midi->substream_transmit = substream;
 	spin_lock_irqsave(&line6->line6midi->send_urb_lock, flags);

 	if (line6->line6midi->num_active_send_urbs == 0)
 		line6_midi_transmit(substream);

 	spin_unlock_irqrestore(&line6->line6midi->send_urb_lock, flags);
 }

 static void line6_midi_output_drain(struct snd_rawmidi_substream *substream)
 {
 	struct usb_line6 *line6 = line6_rawmidi_substream_midi(substream)->line6;
 	wait_queue_head_t *head = &line6->line6midi->send_wait;
 	DECLARE_WAITQUEUE(wait, current);
 	add_wait_queue(head, &wait);
 	current->state = TASK_INTERRUPTIBLE;

 	while (line6->line6midi->num_active_send_urbs > 0)
 		if (signal_pending(current))
 			break;
 		else
 			schedule();

 	current->state = TASK_RUNNING;
 	remove_wait_queue(head, &wait);
 }

 static int line6_midi_input_open(struct snd_rawmidi_substream *substream)
 {
 	return 0;
 }

 static int line6_midi_input_close(struct snd_rawmidi_substream *substream)
 {
 	return 0;
 }

 static void line6_midi_input_trigger(struct snd_rawmidi_substream *substream,
 				     int up)
 {
 	struct usb_line6 *line6 = line6_rawmidi_substream_midi(substream)->line6;

 	if (up)
 		line6->line6midi->substream_receive = substream;
 	else
 		line6->line6midi->substream_receive = 0;
 }

 static struct snd_rawmidi_ops line6_midi_output_ops = {
 	.open = line6_midi_output_open,
 	.close = line6_midi_output_close,
 	.trigger = line6_midi_output_trigger,
 	.drain = line6_midi_output_drain,
 };

 static struct snd_rawmidi_ops line6_midi_input_ops = {
 	.open = line6_midi_input_open,
 	.close = line6_midi_input_close,
 	.trigger = line6_midi_input_trigger,
 };

 /*
 	Cleanup the Line6 MIDI device.
 */
 static void line6_cleanup_midi(struct snd_rawmidi *rmidi)
 {
 }

 /* Create a MIDI device */
 static int snd_line6_new_midi(struct snd_line6_midi *line6midi)
 {
 	struct snd_rawmidi *rmidi;
 	int err;

 	err = snd_rawmidi_new(line6midi->line6->card, "Line6 MIDI", 0, 1, 1,
 			      &rmidi);
 	if (err < 0)
 		return err;

 	rmidi->private_data = line6midi;
 	rmidi->private_free = line6_cleanup_midi;
 	strcpy(rmidi->name, line6midi->line6->properties->name);

 	rmidi->info_flags =
 		SNDRV_RAWMIDI_INFO_OUTPUT |
 		SNDRV_RAWMIDI_INFO_INPUT |
 		SNDRV_RAWMIDI_INFO_DUPLEX;

 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
 			    &line6_midi_output_ops);
 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
 			    &line6_midi_input_ops);
 	return 0;
 }

 /*
 	"read" request on "midi_mask_transmit" special file.
 */
 static ssize_t midi_get_midi_mask_transmit(struct device *dev,
 					   struct device_attribute *attr,
 					   char *buf)
 {
 	struct usb_interface *interface = to_usb_interface(dev);
 	struct usb_line6 *line6 = usb_get_intfdata(interface);
 	return sprintf(buf, "%d\n", line6->line6midi->midi_mask_transmit);
 }

 /*
 	"write" request on "midi_mask" special file.
 */
 static ssize_t midi_set_midi_mask_transmit(struct device *dev,
 					   struct device_attribute *attr,
 					   const char *buf, size_t count)
 {
 	struct usb_interface *interface = to_usb_interface(dev);
 	struct usb_line6 *line6 = usb_get_intfdata(interface);
 	unsigned long value;
 	int ret;

 	ret = strict_strtoul(buf, 10, &value);
 	if (ret)
 		return ret;

 	line6->line6midi->midi_mask_transmit = value;
 	return count;
 }

 /*
 	"read" request on "midi_mask_receive" special file.
 */
 static ssize_t midi_get_midi_mask_receive(struct device *dev,
 					  struct device_attribute *attr,
 					  char *buf)
 {
 	struct usb_interface *interface = to_usb_interface(dev);
 	struct usb_line6 *line6 = usb_get_intfdata(interface);
 	return sprintf(buf, "%d\n", line6->line6midi->midi_mask_receive);
 }

 /*
 	"write" request on "midi_mask" special file.
 */
 static ssize_t midi_set_midi_mask_receive(struct device *dev,
 					  struct device_attribute *attr,
 					  const char *buf, size_t count)
 {
 	struct usb_interface *interface = to_usb_interface(dev);
 	struct usb_line6 *line6 = usb_get_intfdata(interface);
 	unsigned long value;
 	int ret;

 	ret = strict_strtoul(buf, 10, &value);
 	if (ret)
 		return ret;

 	line6->line6midi->midi_mask_receive = value;
 	return count;
 }

 static DEVICE_ATTR(midi_mask_transmit, S_IWUSR | S_IRUGO, midi_get_midi_mask_transmit, midi_set_midi_mask_transmit);
 static DEVICE_ATTR(midi_mask_receive, S_IWUSR | S_IRUGO, midi_get_midi_mask_receive, midi_set_midi_mask_receive);

 /* MIDI device destructor */
 static int snd_line6_midi_free(struct snd_device *device)
 {
 	struct snd_line6_midi *line6midi = device->device_data;
 	device_remove_file(line6midi->line6->ifcdev, &dev_attr_midi_mask_transmit);
 	device_remove_file(line6midi->line6->ifcdev, &dev_attr_midi_mask_receive);
 	midibuf_destroy(&line6midi->midibuf_in);
 	midibuf_destroy(&line6midi->midibuf_out);
 	return 0;
 }

 /*
 	Initialize the Line6 MIDI subsystem.
 */
 int line6_init_midi(struct usb_line6 *line6)
 {
 	static struct snd_device_ops midi_ops = {
 		.dev_free = snd_line6_midi_free,
 	};

 	int err;
 	struct snd_line6_midi *line6midi;

 	if (!(line6->properties->capabilities & LINE6_BIT_CONTROL))
 		return 0;  /* skip MIDI initialization and report success */

 	line6midi = kzalloc(sizeof(struct snd_line6_midi), GFP_KERNEL);

 	if (line6midi == NULL)
 		return -ENOMEM;

 	err = midibuf_init(&line6midi->midibuf_in, MIDI_BUFFER_SIZE, 0);
 	if (err < 0)
 		return err;

 	err = midibuf_init(&line6midi->midibuf_out, MIDI_BUFFER_SIZE, 1);
 	if (err < 0)
 		return err;

 	line6midi->line6 = line6;
 	line6midi->midi_mask_transmit = 1;
 	line6midi->midi_mask_receive = 4;
 	line6->line6midi = line6midi;

 	err = snd_device_new(line6->card, SNDRV_DEV_RAWMIDI, line6midi,
 			     &midi_ops);
 	if (err < 0)
 		return err;

 	snd_card_set_dev(line6->card, line6->ifcdev);

 	err = snd_line6_new_midi(line6midi);
 	if (err < 0)
 		return err;

 	err = device_create_file(line6->ifcdev, &dev_attr_midi_mask_transmit);
 	if (err < 0)
 		return err;

 	err = device_create_file(line6->ifcdev, &dev_attr_midi_mask_receive);
 	if (err < 0)
 		return err;

 	init_waitqueue_head(&line6midi->send_wait);
 	spin_lock_init(&line6midi->send_urb_lock);
 	spin_lock_init(&line6midi->midi_transmit_lock);
 	return 0;
 }
	/*
	* Line6 Linux USB driver - 0.8.0
	*
	* Copyright (C) 2004-2009 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 "driver.h"

	#include <linux/usb.h>
	#include <linux/slab.h>

	#include <sound/core.h>
	#include <sound/rawmidi.h>

	#include "audio.h"
	#include "midi.h"
	#include "pod.h"
	#include "usbdefs.h"


	#define USE_MIDIBUF 1
	#define OUTPUT_DUMP_ONLY 0


	#define line6_rawmidi_substream_midi(substream) \
	((struct snd_line6_midi *)((substream)->rmidi->private_data))


	static int send_midi_async(struct usb_line6 line6, unsigned char data,
	int length);


	/*
	Pass data received via USB to MIDI.
	*/
	void line6_midi_receive(struct usb_line6 line6, unsigned char data,
	int length)
	{
	if (line6->line6midi->substream_receive)
	snd_rawmidi_receive(line6->line6midi->substream_receive,
	data, length);
	}

	/*
	Read data from MIDI buffer and transmit them via USB.
	*/
	static void line6_midi_transmit(struct snd_rawmidi_substream *substream)
	{
	struct usb_line6 *line6 = line6_rawmidi_substream_midi(substream)->line6;
	struct snd_line6_midi *line6midi = line6->line6midi;
	struct MidiBuffer *mb = &line6midi->midibuf_out;
	unsigned long flags;
	unsigned char chunk[line6->max_packet_size];
	int req, done;

	spin_lock_irqsave(&line6->line6midi->midi_transmit_lock, flags);

	for (;;) {
	req = min(midibuf_bytes_free(mb), line6->max_packet_size);
	done = snd_rawmidi_transmit_peek(substream, chunk, req);

	if (done == 0)
	break;

	#if DO_DUMP_MIDI_SEND
	line6_write_hexdump(line6, 's', chunk, done);
	#endif
	midibuf_write(mb, chunk, done);
	snd_rawmidi_transmit_ack(substream, done);
	}

	for (;;) {
	done = midibuf_read(mb, chunk, line6->max_packet_size);

	if (done == 0)
	break;

	if (midibuf_skip_message(mb, line6midi->midi_mask_transmit))
	continue;

	send_midi_async(line6, chunk, done);
	}

	spin_unlock_irqrestore(&line6->line6midi->midi_transmit_lock, flags);
	}

	/*
	Notification of completion of MIDI transmission.
	*/
	static void midi_sent(struct urb *urb)
	{
	unsigned long flags;
	int status;
	int num;
	struct usb_line6 line6 = (struct usb_line6 )urb->context;

	status = urb->status;
	kfree(urb->transfer_buffer);
	usb_free_urb(urb);

	if (status == -ESHUTDOWN)
	return;

	spin_lock_irqsave(&line6->line6midi->send_urb_lock, flags);
	num = --line6->line6midi->num_active_send_urbs;

	if (num == 0) {
	line6_midi_transmit(line6->line6midi->substream_transmit);
	num = line6->line6midi->num_active_send_urbs;
	}

	if (num == 0)
	wake_up_interruptible(&line6->line6midi->send_wait);

	spin_unlock_irqrestore(&line6->line6midi->send_urb_lock, flags);
	}

	/*
	Send an asynchronous MIDI message.
	Assumes that line6->line6midi->send_urb_lock is held
	(i.e., this function is serialized).
	*/
	static int send_midi_async(struct usb_line6 line6, unsigned char data,
	int length)
	{
	struct urb *urb;
	int retval;
	unsigned char *transfer_buffer;

	urb = usb_alloc_urb(0, GFP_ATOMIC);

	if (urb == 0) {
	dev_err(line6->ifcdev, "Out of memory\n");
	return -ENOMEM;
	}

	#if DO_DUMP_URB_SEND
	line6_write_hexdump(line6, 'S', data, length);
	#endif

	transfer_buffer = kmalloc(length, GFP_ATOMIC);

	if (transfer_buffer == 0) {
	usb_free_urb(urb);
	dev_err(line6->ifcdev, "Out of memory\n");
	return -ENOMEM;
	}

	memcpy(transfer_buffer, data, length);
	usb_fill_int_urb(urb, line6->usbdev,
	usb_sndbulkpipe(line6->usbdev,
	line6->ep_control_write),
	transfer_buffer, length, midi_sent, line6,
	line6->interval);
	urb->actual_length = 0;
	retval = usb_submit_urb(urb, GFP_ATOMIC);

	if (retval < 0) {
	dev_err(line6->ifcdev, "usb_submit_urb failed\n");
	usb_free_urb(urb);
	return -EINVAL;
	}

	++line6->line6midi->num_active_send_urbs;

	switch (line6->usbdev->descriptor.idProduct) {
	case LINE6_DEVID_BASSPODXT:
	case LINE6_DEVID_BASSPODXTLIVE:
	case LINE6_DEVID_BASSPODXTPRO:
	case LINE6_DEVID_PODXT:
	case LINE6_DEVID_PODXTLIVE:
	case LINE6_DEVID_PODXTPRO:
	case LINE6_DEVID_POCKETPOD:
	pod_midi_postprocess((struct usb_line6_pod *)line6, data,
	length);
	break;

	default:
	MISSING_CASE;
	}

	return 0;
	}

	static int line6_midi_output_open(struct snd_rawmidi_substream *substream)
	{
	return 0;
	}

	static int line6_midi_output_close(struct snd_rawmidi_substream *substream)
	{
	return 0;
	}

	static void line6_midi_output_trigger(struct snd_rawmidi_substream *substream,
	int up)
	{
	unsigned long flags;
	struct usb_line6 *line6 = line6_rawmidi_substream_midi(substream)->line6;

	line6->line6midi->substream_transmit = substream;
	spin_lock_irqsave(&line6->line6midi->send_urb_lock, flags);

	if (line6->line6midi->num_active_send_urbs == 0)
	line6_midi_transmit(substream);

	spin_unlock_irqrestore(&line6->line6midi->send_urb_lock, flags);
	}

	static void line6_midi_output_drain(struct snd_rawmidi_substream *substream)
	{
	struct usb_line6 *line6 = line6_rawmidi_substream_midi(substream)->line6;
	wait_queue_head_t *head = &line6->line6midi->send_wait;
	DECLARE_WAITQUEUE(wait, current);
	add_wait_queue(head, &wait);
	current->state = TASK_INTERRUPTIBLE;

	while (line6->line6midi->num_active_send_urbs > 0)
	if (signal_pending(current))
	break;
	else
	schedule();

	current->state = TASK_RUNNING;
	remove_wait_queue(head, &wait);
	}

	static int line6_midi_input_open(struct snd_rawmidi_substream *substream)
	{
	return 0;
	}

	static int line6_midi_input_close(struct snd_rawmidi_substream *substream)
	{
	return 0;
	}

	static void line6_midi_input_trigger(struct snd_rawmidi_substream *substream,
	int up)
	{
	struct usb_line6 *line6 = line6_rawmidi_substream_midi(substream)->line6;

	if (up)
	line6->line6midi->substream_receive = substream;
	else
	line6->line6midi->substream_receive = 0;
	}

	static struct snd_rawmidi_ops line6_midi_output_ops = {
	.open = line6_midi_output_open,
	.close = line6_midi_output_close,
	.trigger = line6_midi_output_trigger,
	.drain = line6_midi_output_drain,
	};

	static struct snd_rawmidi_ops line6_midi_input_ops = {
	.open = line6_midi_input_open,
	.close = line6_midi_input_close,
	.trigger = line6_midi_input_trigger,
	};

	/*
	Cleanup the Line6 MIDI device.
	*/
	static void line6_cleanup_midi(struct snd_rawmidi *rmidi)
	{
	}

	/* Create a MIDI device */
	static int snd_line6_new_midi(struct snd_line6_midi *line6midi)
	{
	struct snd_rawmidi *rmidi;
	int err;

	err = snd_rawmidi_new(line6midi->line6->card, "Line6 MIDI", 0, 1, 1,
	&rmidi);
	if (err < 0)
	return err;

	rmidi->private_data = line6midi;
	rmidi->private_free = line6_cleanup_midi;
	strcpy(rmidi->name, line6midi->line6->properties->name);

	rmidi->info_flags =
	SNDRV_RAWMIDI_INFO_OUTPUT \|
	SNDRV_RAWMIDI_INFO_INPUT \|
	SNDRV_RAWMIDI_INFO_DUPLEX;

	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
	&line6_midi_output_ops);
	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
	&line6_midi_input_ops);
	return 0;
	}

	/*
	"read" request on "midi_mask_transmit" special file.
	*/
	static ssize_t midi_get_midi_mask_transmit(struct device *dev,
	struct device_attribute *attr,
	char *buf)
	{
	struct usb_interface *interface = to_usb_interface(dev);
	struct usb_line6 *line6 = usb_get_intfdata(interface);
	return sprintf(buf, "%d\n", line6->line6midi->midi_mask_transmit);
	}

	/*
	"write" request on "midi_mask" special file.
	*/
	static ssize_t midi_set_midi_mask_transmit(struct device *dev,
	struct device_attribute *attr,
	const char *buf, size_t count)
	{
	struct usb_interface *interface = to_usb_interface(dev);
	struct usb_line6 *line6 = usb_get_intfdata(interface);
	unsigned long value;
	int ret;

	ret = strict_strtoul(buf, 10, &value);
	if (ret)
	return ret;

	line6->line6midi->midi_mask_transmit = value;
	return count;
	}

	/*
	"read" request on "midi_mask_receive" special file.
	*/
	static ssize_t midi_get_midi_mask_receive(struct device *dev,
	struct device_attribute *attr,
	char *buf)
	{
	struct usb_interface *interface = to_usb_interface(dev);
	struct usb_line6 *line6 = usb_get_intfdata(interface);
	return sprintf(buf, "%d\n", line6->line6midi->midi_mask_receive);
	}

	/*
	"write" request on "midi_mask" special file.
	*/
	static ssize_t midi_set_midi_mask_receive(struct device *dev,
	struct device_attribute *attr,
	const char *buf, size_t count)
	{
	struct usb_interface *interface = to_usb_interface(dev);
	struct usb_line6 *line6 = usb_get_intfdata(interface);
	unsigned long value;
	int ret;

	ret = strict_strtoul(buf, 10, &value);
	if (ret)
	return ret;

	line6->line6midi->midi_mask_receive = value;
	return count;
	}

	static DEVICE_ATTR(midi_mask_transmit, S_IWUSR \| S_IRUGO, midi_get_midi_mask_transmit, midi_set_midi_mask_transmit);
	static DEVICE_ATTR(midi_mask_receive, S_IWUSR \| S_IRUGO, midi_get_midi_mask_receive, midi_set_midi_mask_receive);

	/* MIDI device destructor */
	static int snd_line6_midi_free(struct snd_device *device)
	{
	struct snd_line6_midi *line6midi = device->device_data;
	device_remove_file(line6midi->line6->ifcdev, &dev_attr_midi_mask_transmit);
	device_remove_file(line6midi->line6->ifcdev, &dev_attr_midi_mask_receive);
	midibuf_destroy(&line6midi->midibuf_in);
	midibuf_destroy(&line6midi->midibuf_out);
	return 0;
	}

	/*
	Initialize the Line6 MIDI subsystem.
	*/
	int line6_init_midi(struct usb_line6 *line6)
	{
	static struct snd_device_ops midi_ops = {
	.dev_free = snd_line6_midi_free,
	};

	int err;
	struct snd_line6_midi *line6midi;

	if (!(line6->properties->capabilities & LINE6_BIT_CONTROL))
	return 0; /* skip MIDI initialization and report success */

	line6midi = kzalloc(sizeof(struct snd_line6_midi), GFP_KERNEL);

	if (line6midi == NULL)
	return -ENOMEM;

	err = midibuf_init(&line6midi->midibuf_in, MIDI_BUFFER_SIZE, 0);
	if (err < 0)
	return err;

	err = midibuf_init(&line6midi->midibuf_out, MIDI_BUFFER_SIZE, 1);
	if (err < 0)
	return err;

	line6midi->line6 = line6;
	line6midi->midi_mask_transmit = 1;
	line6midi->midi_mask_receive = 4;
	line6->line6midi = line6midi;

	err = snd_device_new(line6->card, SNDRV_DEV_RAWMIDI, line6midi,
	&midi_ops);
	if (err < 0)
	return err;

	snd_card_set_dev(line6->card, line6->ifcdev);

	err = snd_line6_new_midi(line6midi);
	if (err < 0)
	return err;

	err = device_create_file(line6->ifcdev, &dev_attr_midi_mask_transmit);
	if (err < 0)
	return err;

	err = device_create_file(line6->ifcdev, &dev_attr_midi_mask_receive);
	if (err < 0)
	return err;

	init_waitqueue_head(&line6midi->send_wait);
	spin_lock_init(&line6midi->send_urb_lock);
	spin_lock_init(&line6midi->midi_transmit_lock);
	return 0;
	}