sound/firewire/speakers.c

/*
 * OXFW970-based speakers driver
 *
 * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
 * Licensed under the terms of the GNU General Public License, version 2.
 */

#include <linux/device.h>
#include <linux/firewire.h>
#include <linux/firewire-constants.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <sound/control.h>
#include <sound/core.h>
#include <sound/initval.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include "cmp.h"
#include "fcp.h"
#include "amdtp.h"
#include "lib.h"

#define OXFORD_FIRMWARE_ID_ADDRESS	(CSR_REGISTER_BASE + 0x50000)
/* 0x970?vvvv or 0x971?vvvv, where vvvv = firmware version */

#define OXFORD_HARDWARE_ID_ADDRESS	(CSR_REGISTER_BASE + 0x90020)
#define OXFORD_HARDWARE_ID_OXFW970	0x39443841
#define OXFORD_HARDWARE_ID_OXFW971	0x39373100

#define VENDOR_GRIFFIN		0x001292
#define VENDOR_LACIE		0x00d04b

#define SPECIFIER_1394TA	0x00a02d
#define VERSION_AVC		0x010001

struct device_info {
	const char *driver_name;
	const char *short_name;
	const char *long_name;
	int (*pcm_constraints)(struct snd_pcm_runtime *runtime);
	unsigned int mixer_channels;
	u8 mute_fb_id;
	u8 volume_fb_id;
};

struct fwspk {
	struct snd_card *card;
	struct fw_unit *unit;
	const struct device_info *device_info;
	struct snd_pcm_substream *pcm;
	struct mutex mutex;
	struct cmp_connection connection;
	struct amdtp_out_stream stream;
	bool stream_running;
	bool mute;
	s16 volume[6];
	s16 volume_min;
	s16 volume_max;
};

MODULE_DESCRIPTION("FireWire speakers driver");
MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
MODULE_LICENSE("GPL v2");

static int firewave_rate_constraint(struct snd_pcm_hw_params *params,
				    struct snd_pcm_hw_rule *rule)
{
	static unsigned int stereo_rates[] = { 48000, 96000 };
	struct snd_interval *channels =
			hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
	struct snd_interval *rate =
			hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);

	/* two channels work only at 48/96 kHz */
	if (snd_interval_max(channels) < 6)
		return snd_interval_list(rate, 2, stereo_rates, 0);
	return 0;
}

static int firewave_channels_constraint(struct snd_pcm_hw_params *params,
					struct snd_pcm_hw_rule *rule)
{
	static const struct snd_interval all_channels = { .min = 6, .max = 6 };
	struct snd_interval *rate =
			hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
	struct snd_interval *channels =
			hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);

	/* 32/44.1 kHz work only with all six channels */
	if (snd_interval_max(rate) < 48000)
		return snd_interval_refine(channels, &all_channels);
	return 0;
}

static int firewave_constraints(struct snd_pcm_runtime *runtime)
{
	static unsigned int channels_list[] = { 2, 6 };
	static struct snd_pcm_hw_constraint_list channels_list_constraint = {
		.count = 2,
		.list = channels_list,
	};
	int err;

	runtime->hw.rates = SNDRV_PCM_RATE_32000 |
			    SNDRV_PCM_RATE_44100 |
			    SNDRV_PCM_RATE_48000 |
			    SNDRV_PCM_RATE_96000;
	runtime->hw.channels_max = 6;

	err = snd_pcm_hw_constraint_list(runtime, 0,
					 SNDRV_PCM_HW_PARAM_CHANNELS,
					 &channels_list_constraint);
	if (err < 0)
		return err;
	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
				  firewave_rate_constraint, NULL,
				  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
	if (err < 0)
		return err;
	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
				  firewave_channels_constraint, NULL,
				  SNDRV_PCM_HW_PARAM_RATE, -1);
	if (err < 0)
		return err;

	return 0;
}

static int lacie_speakers_constraints(struct snd_pcm_runtime *runtime)
{
	runtime->hw.rates = SNDRV_PCM_RATE_32000 |
			    SNDRV_PCM_RATE_44100 |
			    SNDRV_PCM_RATE_48000 |
			    SNDRV_PCM_RATE_88200 |
			    SNDRV_PCM_RATE_96000;

	return 0;
}

static int fwspk_open(struct snd_pcm_substream *substream)
{
	static const struct snd_pcm_hardware hardware = {
		.info = SNDRV_PCM_INFO_MMAP |
			SNDRV_PCM_INFO_MMAP_VALID |
			SNDRV_PCM_INFO_BATCH |
			SNDRV_PCM_INFO_INTERLEAVED |
			SNDRV_PCM_INFO_BLOCK_TRANSFER,
		.formats = AMDTP_OUT_PCM_FORMAT_BITS,
		.channels_min = 2,
		.channels_max = 2,
		.buffer_bytes_max = 4 * 1024 * 1024,
		.period_bytes_min = 1,
		.period_bytes_max = UINT_MAX,
		.periods_min = 1,
		.periods_max = UINT_MAX,
	};
	struct fwspk *fwspk = substream->private_data;
	struct snd_pcm_runtime *runtime = substream->runtime;
	int err;

	runtime->hw = hardware;

	err = fwspk->device_info->pcm_constraints(runtime);
	if (err < 0)
		return err;
	err = snd_pcm_limit_hw_rates(runtime);
	if (err < 0)
		return err;

	err = snd_pcm_hw_constraint_minmax(runtime,
					   SNDRV_PCM_HW_PARAM_PERIOD_TIME,
					   5000, 8192000);
	if (err < 0)
		return err;

	err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
	if (err < 0)
		return err;

	return 0;
}

static int fwspk_close(struct snd_pcm_substream *substream)
{
	return 0;
}

static void fwspk_stop_stream(struct fwspk *fwspk)
{
	if (fwspk->stream_running) {
		amdtp_out_stream_stop(&fwspk->stream);
		cmp_connection_break(&fwspk->connection);
		fwspk->stream_running = false;
	}
}

static int fwspk_set_rate(struct fwspk *fwspk, unsigned int sfc)
{
	u8 *buf;
	int err;

	buf = kmalloc(8, GFP_KERNEL);
	if (!buf)
		return -ENOMEM;

	buf[0] = 0x00;		/* AV/C, CONTROL */
	buf[1] = 0xff;		/* unit */
	buf[2] = 0x19;		/* INPUT PLUG SIGNAL FORMAT */
	buf[3] = 0x00;		/* plug 0 */
	buf[4] = 0x90;		/* format: audio */
	buf[5] = 0x00 | sfc;	/* AM824, frequency */
	buf[6] = 0xff;		/* SYT (not used) */
	buf[7] = 0xff;

	err = fcp_avc_transaction(fwspk->unit, buf, 8, buf, 8,
				  BIT(1) | BIT(2) | BIT(3) | BIT(4) | BIT(5));
	if (err < 0)
		goto error;
	if (err < 6 || buf[0] != 0x09 /* ACCEPTED */) {
		dev_err(&fwspk->unit->device, "failed to set sample rate\n");
		err = -EIO;
		goto error;
	}

	err = 0;

error:
	kfree(buf);

	return err;
}

static int fwspk_hw_params(struct snd_pcm_substream *substream,
			   struct snd_pcm_hw_params *hw_params)
{
	struct fwspk *fwspk = substream->private_data;
	int err;

	mutex_lock(&fwspk->mutex);
	fwspk_stop_stream(fwspk);
	mutex_unlock(&fwspk->mutex);

	err = snd_pcm_lib_alloc_vmalloc_buffer(substream,
					       params_buffer_bytes(hw_params));
	if (err < 0)
		goto error;

	amdtp_out_stream_set_rate(&fwspk->stream, params_rate(hw_params));
	amdtp_out_stream_set_pcm(&fwspk->stream, params_channels(hw_params));

	amdtp_out_stream_set_pcm_format(&fwspk->stream,
					params_format(hw_params));

	err = fwspk_set_rate(fwspk, fwspk->stream.sfc);
	if (err < 0)
		goto err_buffer;

	return 0;

err_buffer:
	snd_pcm_lib_free_vmalloc_buffer(substream);
error:
	return err;
}

static int fwspk_hw_free(struct snd_pcm_substream *substream)
{
	struct fwspk *fwspk = substream->private_data;

	mutex_lock(&fwspk->mutex);
	fwspk_stop_stream(fwspk);
	mutex_unlock(&fwspk->mutex);

	return snd_pcm_lib_free_vmalloc_buffer(substream);
}

static int fwspk_prepare(struct snd_pcm_substream *substream)
{
	struct fwspk *fwspk = substream->private_data;
	int err;

	mutex_lock(&fwspk->mutex);

	if (amdtp_out_streaming_error(&fwspk->stream))
		fwspk_stop_stream(fwspk);

	if (!fwspk->stream_running) {
		err = cmp_connection_establish(&fwspk->connection,
			amdtp_out_stream_get_max_payload(&fwspk->stream));
		if (err < 0)
			goto err_mutex;

		err = amdtp_out_stream_start(&fwspk->stream,
					fwspk->connection.resources.channel,
					fwspk->connection.speed);
		if (err < 0)
			goto err_connection;

		fwspk->stream_running = true;
	}

	mutex_unlock(&fwspk->mutex);

	amdtp_out_stream_pcm_prepare(&fwspk->stream);

	return 0;

err_connection:
	cmp_connection_break(&fwspk->connection);
err_mutex:
	mutex_unlock(&fwspk->mutex);

	return err;
}

static int fwspk_trigger(struct snd_pcm_substream *substream, int cmd)
{
	struct fwspk *fwspk = substream->private_data;
	struct snd_pcm_substream *pcm;

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
		pcm = substream;
		break;
	case SNDRV_PCM_TRIGGER_STOP:
		pcm = NULL;
		break;
	default:
		return -EINVAL;
	}
	amdtp_out_stream_pcm_trigger(&fwspk->stream, pcm);
	return 0;
}

static snd_pcm_uframes_t fwspk_pointer(struct snd_pcm_substream *substream)
{
	struct fwspk *fwspk = substream->private_data;

	return amdtp_out_stream_pcm_pointer(&fwspk->stream);
}

static int fwspk_create_pcm(struct fwspk *fwspk)
{
	static struct snd_pcm_ops ops = {
		.open      = fwspk_open,
		.close     = fwspk_close,
		.ioctl     = snd_pcm_lib_ioctl,
		.hw_params = fwspk_hw_params,
		.hw_free   = fwspk_hw_free,
		.prepare   = fwspk_prepare,
		.trigger   = fwspk_trigger,
		.pointer   = fwspk_pointer,
		.page      = snd_pcm_lib_get_vmalloc_page,
		.mmap      = snd_pcm_lib_mmap_vmalloc,
	};
	struct snd_pcm *pcm;
	int err;

	err = snd_pcm_new(fwspk->card, "OXFW970", 0, 1, 0, &pcm);
	if (err < 0)
		return err;
	pcm->private_data = fwspk;
	strcpy(pcm->name, fwspk->device_info->short_name);
	fwspk->pcm = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
	fwspk->pcm->ops = &ops;
	return 0;
}

enum control_action { CTL_READ, CTL_WRITE };
enum control_attribute {
	CTL_MIN		= 0x02,
	CTL_MAX		= 0x03,
	CTL_CURRENT	= 0x10,
};

static int fwspk_mute_command(struct fwspk *fwspk, bool *value,
			      enum control_action action)
{
	u8 *buf;
	u8 response_ok;
	int err;

	buf = kmalloc(11, GFP_KERNEL);
	if (!buf)
		return -ENOMEM;

	if (action == CTL_READ) {
		buf[0] = 0x01;		/* AV/C, STATUS */
		response_ok = 0x0c;	/*       STABLE */
	} else {
		buf[0] = 0x00;		/* AV/C, CONTROL */
		response_ok = 0x09;	/*       ACCEPTED */
	}
	buf[1] = 0x08;			/* audio unit 0 */
	buf[2] = 0xb8;			/* FUNCTION BLOCK */
	buf[3] = 0x81;			/* function block type: feature */
	buf[4] = fwspk->device_info->mute_fb_id; /* function block ID */
	buf[5] = 0x10;			/* control attribute: current */
	buf[6] = 0x02;			/* selector length */
	buf[7] = 0x00;			/* audio channel number */
	buf[8] = 0x01;			/* control selector: mute */
	buf[9] = 0x01;			/* control data length */
	if (action == CTL_READ)
		buf[10] = 0xff;
	else
		buf[10] = *value ? 0x70 : 0x60;

	err = fcp_avc_transaction(fwspk->unit, buf, 11, buf, 11, 0x3fe);
	if (err < 0)
		goto error;
	if (err < 11) {
		dev_err(&fwspk->unit->device, "short FCP response\n");
		err = -EIO;
		goto error;
	}
	if (buf[0] != response_ok) {
		dev_err(&fwspk->unit->device, "mute command failed\n");
		err = -EIO;
		goto error;
	}
	if (action == CTL_READ)
		*value = buf[10] == 0x70;

	err = 0;

error:
	kfree(buf);

	return err;
}

static int fwspk_volume_command(struct fwspk *fwspk, s16 *value,
				unsigned int channel,
				enum control_attribute attribute,
				enum control_action action)
{
	u8 *buf;
	u8 response_ok;
	int err;

	buf = kmalloc(12, GFP_KERNEL);
	if (!buf)
		return -ENOMEM;

	if (action == CTL_READ) {
		buf[0] = 0x01;		/* AV/C, STATUS */
		response_ok = 0x0c;	/*       STABLE */
	} else {
		buf[0] = 0x00;		/* AV/C, CONTROL */
		response_ok = 0x09;	/*       ACCEPTED */
	}
	buf[1] = 0x08;			/* audio unit 0 */
	buf[2] = 0xb8;			/* FUNCTION BLOCK */
	buf[3] = 0x81;			/* function block type: feature */
	buf[4] = fwspk->device_info->volume_fb_id; /* function block ID */
	buf[5] = attribute;		/* control attribute */
	buf[6] = 0x02;			/* selector length */
	buf[7] = channel;		/* audio channel number */
	buf[8] = 0x02;			/* control selector: volume */
	buf[9] = 0x02;			/* control data length */
	if (action == CTL_READ) {
		buf[10] = 0xff;
		buf[11] = 0xff;
	} else {
		buf[10] = *value >> 8;
		buf[11] = *value;
	}

	err = fcp_avc_transaction(fwspk->unit, buf, 12, buf, 12, 0x3fe);
	if (err < 0)
		goto error;
	if (err < 12) {
		dev_err(&fwspk->unit->device, "short FCP response\n");
		err = -EIO;
		goto error;
	}
	if (buf[0] != response_ok) {
		dev_err(&fwspk->unit->device, "volume command failed\n");
		err = -EIO;
		goto error;
	}
	if (action == CTL_READ)
		*value = (buf[10] << 8) | buf[11];

	err = 0;

error:
	kfree(buf);

	return err;
}

static int fwspk_mute_get(struct snd_kcontrol *control,
			  struct snd_ctl_elem_value *value)
{
	struct fwspk *fwspk = control->private_data;

	value->value.integer.value[0] = !fwspk->mute;

	return 0;
}

static int fwspk_mute_put(struct snd_kcontrol *control,
			  struct snd_ctl_elem_value *value)
{
	struct fwspk *fwspk = control->private_data;
	bool mute;
	int err;

	mute = !value->value.integer.value[0];

	if (mute == fwspk->mute)
		return 0;

	err = fwspk_mute_command(fwspk, &mute, CTL_WRITE);
	if (err < 0)
		return err;
	fwspk->mute = mute;

	return 1;
}

static int fwspk_volume_info(struct snd_kcontrol *control,
			     struct snd_ctl_elem_info *info)
{
	struct fwspk *fwspk = control->private_data;

	info->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
	info->count = fwspk->device_info->mixer_channels;
	info->value.integer.min = fwspk->volume_min;
	info->value.integer.max = fwspk->volume_max;

	return 0;
}

static const u8 channel_map[6] = { 0, 1, 4, 5, 2, 3 };

static int fwspk_volume_get(struct snd_kcontrol *control,
			    struct snd_ctl_elem_value *value)
{
	struct fwspk *fwspk = control->private_data;
	unsigned int i;

	for (i = 0; i < fwspk->device_info->mixer_channels; ++i)
		value->value.integer.value[channel_map[i]] = fwspk->volume[i];

	return 0;
}

static int fwspk_volume_put(struct snd_kcontrol *control,
			  struct snd_ctl_elem_value *value)
{
	struct fwspk *fwspk = control->private_data;
	unsigned int i, changed_channels;
	bool equal_values = true;
	s16 volume;
	int err;

	for (i = 0; i < fwspk->device_info->mixer_channels; ++i) {
		if (value->value.integer.value[i] < fwspk->volume_min ||
		    value->value.integer.value[i] > fwspk->volume_max)
			return -EINVAL;
		if (value->value.integer.value[i] !=
		    value->value.integer.value[0])
			equal_values = false;
	}

	changed_channels = 0;
	for (i = 0; i < fwspk->device_info->mixer_channels; ++i)
		if (value->value.integer.value[channel_map[i]] !=
							fwspk->volume[i])
			changed_channels |= 1 << (i + 1);

	if (equal_values && changed_channels != 0)
		changed_channels = 1 << 0;

	for (i = 0; i <= fwspk->device_info->mixer_channels; ++i) {
		volume = value->value.integer.value[channel_map[i ? i - 1 : 0]];
		if (changed_channels & (1 << i)) {
			err = fwspk_volume_command(fwspk, &volume, i,
						   CTL_CURRENT, CTL_WRITE);
			if (err < 0)
				return err;
		}
		if (i > 0)
			fwspk->volume[i - 1] = volume;
	}

	return changed_channels != 0;
}

static int fwspk_create_mixer(struct fwspk *fwspk)
{
	static const struct snd_kcontrol_new controls[] = {
		{
			.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
			.name = "PCM Playback Switch",
			.info = snd_ctl_boolean_mono_info,
			.get = fwspk_mute_get,
			.put = fwspk_mute_put,
		},
		{
			.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
			.name = "PCM Playback Volume",
			.info = fwspk_volume_info,
			.get = fwspk_volume_get,
			.put = fwspk_volume_put,
		},
	};
	unsigned int i, first_ch;
	int err;

	err = fwspk_volume_command(fwspk, &fwspk->volume_min,
				   0, CTL_MIN, CTL_READ);
	if (err < 0)
		return err;
	err = fwspk_volume_command(fwspk, &fwspk->volume_max,
				   0, CTL_MAX, CTL_READ);
	if (err < 0)
		return err;

	err = fwspk_mute_command(fwspk, &fwspk->mute, CTL_READ);
	if (err < 0)
		return err;

	first_ch = fwspk->device_info->mixer_channels == 1 ? 0 : 1;
	for (i = 0; i < fwspk->device_info->mixer_channels; ++i) {
		err = fwspk_volume_command(fwspk, &fwspk->volume[i],
					   first_ch + i, CTL_CURRENT, CTL_READ);
		if (err < 0)
			return err;
	}

	for (i = 0; i < ARRAY_SIZE(controls); ++i) {
		err = snd_ctl_add(fwspk->card,
				  snd_ctl_new1(&controls[i], fwspk));
		if (err < 0)
			return err;
	}

	return 0;
}

static u32 fwspk_read_firmware_version(struct fw_unit *unit)
{
	__be32 data;
	int err;

	err = snd_fw_transaction(unit, TCODE_READ_QUADLET_REQUEST,
				 OXFORD_FIRMWARE_ID_ADDRESS, &data, 4);
	return err >= 0 ? be32_to_cpu(data) : 0;
}

static void fwspk_card_free(struct snd_card *card)
{
	struct fwspk *fwspk = card->private_data;
	struct fw_device *dev = fw_parent_device(fwspk->unit);

	amdtp_out_stream_destroy(&fwspk->stream);
	cmp_connection_destroy(&fwspk->connection);
	fw_unit_put(fwspk->unit);
	fw_device_put(dev);
	mutex_destroy(&fwspk->mutex);
}

static const struct device_info *__devinit fwspk_detect(struct fw_device *dev)
{
	static const struct device_info griffin_firewave = {
		.driver_name = "FireWave",
		.short_name  = "FireWave",
		.long_name   = "Griffin FireWave Surround",
		.pcm_constraints = firewave_constraints,
		.mixer_channels = 6,
		.mute_fb_id   = 0x01,
		.volume_fb_id = 0x02,
	};
	static const struct device_info lacie_speakers = {
		.driver_name = "FWSpeakers",
		.short_name  = "FireWire Speakers",
		.long_name   = "LaCie FireWire Speakers",
		.pcm_constraints = lacie_speakers_constraints,
		.mixer_channels = 1,
		.mute_fb_id   = 0x01,
		.volume_fb_id = 0x01,
	};
	struct fw_csr_iterator i;
	int key, value;

	fw_csr_iterator_init(&i, dev->config_rom);
	while (fw_csr_iterator_next(&i, &key, &value))
		if (key == CSR_VENDOR)
			switch (value) {
			case VENDOR_GRIFFIN:
				return &griffin_firewave;
			case VENDOR_LACIE:
				return &lacie_speakers;
			}

	return NULL;
}

static int __devinit fwspk_probe(struct device *unit_dev)
{
	struct fw_unit *unit = fw_unit(unit_dev);
	struct fw_device *fw_dev = fw_parent_device(unit);
	struct snd_card *card;
	struct fwspk *fwspk;
	u32 firmware;
	int err;

	err = snd_card_create(-1, NULL, THIS_MODULE, sizeof(*fwspk), &card);
	if (err < 0)
		return err;
	snd_card_set_dev(card, unit_dev);

	fwspk = card->private_data;
	fwspk->card = card;
	mutex_init(&fwspk->mutex);
	fw_device_get(fw_dev);
	fwspk->unit = fw_unit_get(unit);
	fwspk->device_info = fwspk_detect(fw_dev);
	if (!fwspk->device_info) {
		err = -ENODEV;
		goto err_unit;
	}

	err = cmp_connection_init(&fwspk->connection, unit, 0);
	if (err < 0)
		goto err_unit;

	err = amdtp_out_stream_init(&fwspk->stream, unit, CIP_NONBLOCKING);
	if (err < 0)
		goto err_connection;

	card->private_free = fwspk_card_free;

	strcpy(card->driver, fwspk->device_info->driver_name);
	strcpy(card->shortname, fwspk->device_info->short_name);
	firmware = fwspk_read_firmware_version(unit);
	snprintf(card->longname, sizeof(card->longname),
		 "%s (OXFW%x %04x), GUID %08x%08x at %s, S%d",
		 fwspk->device_info->long_name,
		 firmware >> 20, firmware & 0xffff,
		 fw_dev->config_rom[3], fw_dev->config_rom[4],
		 dev_name(&unit->device), 100 << fw_dev->max_speed);
	strcpy(card->mixername, "OXFW970");

	err = fwspk_create_pcm(fwspk);
	if (err < 0)
		goto error;

	err = fwspk_create_mixer(fwspk);
	if (err < 0)
		goto error;

	err = snd_card_register(card);
	if (err < 0)
		goto error;

	dev_set_drvdata(unit_dev, fwspk);

	return 0;

err_connection:
	cmp_connection_destroy(&fwspk->connection);
err_unit:
	fw_unit_put(fwspk->unit);
	fw_device_put(fw_dev);
	mutex_destroy(&fwspk->mutex);
error:
	snd_card_free(card);
	return err;
}

static int __devexit fwspk_remove(struct device *dev)
{
	struct fwspk *fwspk = dev_get_drvdata(dev);

	mutex_lock(&fwspk->mutex);
	amdtp_out_stream_pcm_abort(&fwspk->stream);
	snd_card_disconnect(fwspk->card);
	fwspk_stop_stream(fwspk);
	mutex_unlock(&fwspk->mutex);

	snd_card_free_when_closed(fwspk->card);

	return 0;
}

static void fwspk_bus_reset(struct fw_unit *unit)
{
	struct fwspk *fwspk = dev_get_drvdata(&unit->device);

	fcp_bus_reset(fwspk->unit);

	if (cmp_connection_update(&fwspk->connection) < 0) {
		mutex_lock(&fwspk->mutex);
		amdtp_out_stream_pcm_abort(&fwspk->stream);
		fwspk_stop_stream(fwspk);
		mutex_unlock(&fwspk->mutex);
		return;
	}

	amdtp_out_stream_update(&fwspk->stream);
}

static const struct ieee1394_device_id fwspk_id_table[] = {
	{
		.match_flags  = IEEE1394_MATCH_VENDOR_ID |
				IEEE1394_MATCH_MODEL_ID |
				IEEE1394_MATCH_SPECIFIER_ID |
				IEEE1394_MATCH_VERSION,
		.vendor_id    = VENDOR_GRIFFIN,
		.model_id     = 0x00f970,
		.specifier_id = SPECIFIER_1394TA,
		.version      = VERSION_AVC,
	},
	{
		.match_flags  = IEEE1394_MATCH_VENDOR_ID |
				IEEE1394_MATCH_MODEL_ID |
				IEEE1394_MATCH_SPECIFIER_ID |
				IEEE1394_MATCH_VERSION,
		.vendor_id    = VENDOR_LACIE,
		.model_id     = 0x00f970,
		.specifier_id = SPECIFIER_1394TA,
		.version      = VERSION_AVC,
	},
	{ }
};
MODULE_DEVICE_TABLE(ieee1394, fwspk_id_table);

static struct fw_driver fwspk_driver = {
	.driver   = {
		.owner	= THIS_MODULE,
		.name	= KBUILD_MODNAME,
		.bus	= &fw_bus_type,
		.probe	= fwspk_probe,
		.remove	= __devexit_p(fwspk_remove),
	},
	.update   = fwspk_bus_reset,
	.id_table = fwspk_id_table,
};

static int __init alsa_fwspk_init(void)
{
	return driver_register(&fwspk_driver.driver);
}

static void __exit alsa_fwspk_exit(void)
{
	driver_unregister(&fwspk_driver.driver);
}

module_init(alsa_fwspk_init);
module_exit(alsa_fwspk_exit);