linux_dsm_epyc7002/sound/firewire/speakers.c

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/*
* 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 mutex mutex;
struct cmp_connection connection;
struct amdtp_out_stream stream;
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, UINT_MAX);
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 (amdtp_out_stream_running(&fwspk->stream)) {
amdtp_out_stream_stop(&fwspk->stream);
cmp_connection_break(&fwspk->connection);
}
}
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_parameters(&fwspk->stream,
params_rate(hw_params),
params_channels(hw_params),
0);
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 (!amdtp_out_stream_running(&fwspk->stream)) {
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;
}
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);
snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &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, 0);
return err >= 0 ? be32_to_cpu(data) : 0;
}
static void fwspk_card_free(struct snd_card *card)
{
struct fwspk *fwspk = card->private_data;
amdtp_out_stream_destroy(&fwspk->stream);
cmp_connection_destroy(&fwspk->connection);
fw_unit_put(fwspk->unit);
mutex_destroy(&fwspk->mutex);
}
static int fwspk_probe(struct fw_unit *unit,
const struct ieee1394_device_id *id)
{
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->device);
fwspk = card->private_data;
fwspk->card = card;
mutex_init(&fwspk->mutex);
fwspk->unit = fw_unit_get(unit);
fwspk->device_info = (const struct device_info *)id->driver_data;
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->device, fwspk);
return 0;
err_connection:
cmp_connection_destroy(&fwspk->connection);
err_unit:
fw_unit_put(fwspk->unit);
mutex_destroy(&fwspk->mutex);
error:
snd_card_free(card);
return err;
}
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) {
amdtp_out_stream_pcm_abort(&fwspk->stream);
mutex_lock(&fwspk->mutex);
fwspk_stop_stream(fwspk);
mutex_unlock(&fwspk->mutex);
return;
}
amdtp_out_stream_update(&fwspk->stream);
}
static void fwspk_remove(struct fw_unit *unit)
{
struct fwspk *fwspk = dev_get_drvdata(&unit->device);
amdtp_out_stream_pcm_abort(&fwspk->stream);
snd_card_disconnect(fwspk->card);
mutex_lock(&fwspk->mutex);
fwspk_stop_stream(fwspk);
mutex_unlock(&fwspk->mutex);
snd_card_free_when_closed(fwspk->card);
}
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,
};
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,
.driver_data = (kernel_ulong_t)&griffin_firewave,
},
{
.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,
.driver_data = (kernel_ulong_t)&lacie_speakers,
},
{ }
};
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,
.update = fwspk_bus_reset,
.remove = fwspk_remove,
.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);