2 * compress_core.c - compress offload core
4 * Copyright (C) 2011 Intel Corporation
5 * Authors: Vinod Koul <vinod.koul@linux.intel.com>
6 * Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; version 2 of the License.
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25 #define FORMAT(fmt) "%s: %d: " fmt, __func__, __LINE__
26 #define pr_fmt(fmt) KBUILD_MODNAME ": " FORMAT(fmt)
28 #include <linux/file.h>
30 #include <linux/list.h>
31 #include <linux/math64.h>
33 #include <linux/mutex.h>
34 #include <linux/poll.h>
35 #include <linux/slab.h>
36 #include <linux/sched.h>
37 #include <linux/types.h>
38 #include <linux/uio.h>
39 #include <linux/uaccess.h>
40 #include <linux/module.h>
41 #include <sound/core.h>
42 #include <sound/initval.h>
43 #include <sound/compress_params.h>
44 #include <sound/compress_offload.h>
45 #include <sound/compress_driver.h>
48 * - add substream support for multiple devices in case of
49 * SND_DYNAMIC_MINORS is not used
50 * - Multiple node representation
51 * driver should be able to register multiple nodes
54 static DEFINE_MUTEX(device_mutex);
56 struct snd_compr_file {
58 struct snd_compr_stream stream;
62 * a note on stream states used:
63 * we use follwing states in the compressed core
64 * SNDRV_PCM_STATE_OPEN: When stream has been opened.
65 * SNDRV_PCM_STATE_SETUP: When stream has been initialized. This is done by
66 * calling SNDRV_COMPRESS_SET_PARAMS. running streams will come to this
67 * state at stop by calling SNDRV_COMPRESS_STOP, or at end of drain.
68 * SNDRV_PCM_STATE_RUNNING: When stream has been started and is
69 * decoding/encoding and rendering/capturing data.
70 * SNDRV_PCM_STATE_DRAINING: When stream is draining current data. This is done
71 * by calling SNDRV_COMPRESS_DRAIN.
72 * SNDRV_PCM_STATE_PAUSED: When stream is paused. This is done by calling
73 * SNDRV_COMPRESS_PAUSE. It can be stopped or resumed by calling
74 * SNDRV_COMPRESS_STOP or SNDRV_COMPRESS_RESUME respectively.
76 static int snd_compr_open(struct inode *inode, struct file *f)
78 struct snd_compr *compr;
79 struct snd_compr_file *data;
80 struct snd_compr_runtime *runtime;
81 enum snd_compr_direction dirn;
82 int maj = imajor(inode);
85 if ((f->f_flags & O_ACCMODE) == O_WRONLY)
86 dirn = SND_COMPRESS_PLAYBACK;
87 else if ((f->f_flags & O_ACCMODE) == O_RDONLY)
88 dirn = SND_COMPRESS_CAPTURE;
93 compr = snd_lookup_minor_data(iminor(inode),
94 SNDRV_DEVICE_TYPE_COMPRESS);
99 pr_err("no device data!!!\n");
103 if (dirn != compr->direction) {
104 pr_err("this device doesn't support this direction\n");
105 snd_card_unref(compr->card);
109 data = kzalloc(sizeof(*data), GFP_KERNEL);
111 snd_card_unref(compr->card);
114 data->stream.ops = compr->ops;
115 data->stream.direction = dirn;
116 data->stream.private_data = compr->private_data;
117 data->stream.device = compr;
118 runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
121 snd_card_unref(compr->card);
124 runtime->state = SNDRV_PCM_STATE_OPEN;
125 init_waitqueue_head(&runtime->sleep);
126 data->stream.runtime = runtime;
127 f->private_data = (void *)data;
128 mutex_lock(&compr->lock);
129 ret = compr->ops->open(&data->stream);
130 mutex_unlock(&compr->lock);
135 snd_card_unref(compr->card);
139 static int snd_compr_free(struct inode *inode, struct file *f)
141 struct snd_compr_file *data = f->private_data;
142 data->stream.ops->free(&data->stream);
143 kfree(data->stream.runtime->buffer);
144 kfree(data->stream.runtime);
149 static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
150 struct snd_compr_tstamp *tstamp)
152 if (!stream->ops->pointer)
154 stream->ops->pointer(stream, tstamp);
155 pr_debug("dsp consumed till %d total %d bytes\n",
156 tstamp->byte_offset, tstamp->copied_total);
157 if (stream->direction == SND_COMPRESS_PLAYBACK)
158 stream->runtime->total_bytes_transferred = tstamp->copied_total;
160 stream->runtime->total_bytes_available = tstamp->copied_total;
164 static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
165 struct snd_compr_avail *avail)
167 memset(avail, 0, sizeof(*avail));
168 snd_compr_update_tstamp(stream, &avail->tstamp);
169 /* Still need to return avail even if tstamp can't be filled in */
171 if (stream->runtime->total_bytes_available == 0 &&
172 stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
173 stream->direction == SND_COMPRESS_PLAYBACK) {
174 pr_debug("detected init and someone forgot to do a write\n");
175 return stream->runtime->buffer_size;
177 pr_debug("app wrote %lld, DSP consumed %lld\n",
178 stream->runtime->total_bytes_available,
179 stream->runtime->total_bytes_transferred);
180 if (stream->runtime->total_bytes_available ==
181 stream->runtime->total_bytes_transferred) {
182 if (stream->direction == SND_COMPRESS_PLAYBACK) {
183 pr_debug("both pointers are same, returning full avail\n");
184 return stream->runtime->buffer_size;
186 pr_debug("both pointers are same, returning no avail\n");
191 avail->avail = stream->runtime->total_bytes_available -
192 stream->runtime->total_bytes_transferred;
193 if (stream->direction == SND_COMPRESS_PLAYBACK)
194 avail->avail = stream->runtime->buffer_size - avail->avail;
196 pr_debug("ret avail as %lld\n", avail->avail);
200 static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
202 struct snd_compr_avail avail;
204 return snd_compr_calc_avail(stream, &avail);
208 snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
210 struct snd_compr_avail ioctl_avail;
213 avail = snd_compr_calc_avail(stream, &ioctl_avail);
214 ioctl_avail.avail = avail;
216 if (copy_to_user((__u64 __user *)arg,
217 &ioctl_avail, sizeof(ioctl_avail)))
222 static int snd_compr_write_data(struct snd_compr_stream *stream,
223 const char __user *buf, size_t count)
227 struct snd_compr_runtime *runtime = stream->runtime;
229 u64 app_pointer = div64_u64(runtime->total_bytes_available,
230 runtime->buffer_size);
231 app_pointer = runtime->total_bytes_available -
232 (app_pointer * runtime->buffer_size);
234 dstn = runtime->buffer + app_pointer;
235 pr_debug("copying %ld at %lld\n",
236 (unsigned long)count, app_pointer);
237 if (count < runtime->buffer_size - app_pointer) {
238 if (copy_from_user(dstn, buf, count))
241 copy = runtime->buffer_size - app_pointer;
242 if (copy_from_user(dstn, buf, copy))
244 if (copy_from_user(runtime->buffer, buf + copy, count - copy))
247 /* if DSP cares, let it know data has been written */
248 if (stream->ops->ack)
249 stream->ops->ack(stream, count);
253 static ssize_t snd_compr_write(struct file *f, const char __user *buf,
254 size_t count, loff_t *offset)
256 struct snd_compr_file *data = f->private_data;
257 struct snd_compr_stream *stream;
261 if (snd_BUG_ON(!data))
264 stream = &data->stream;
265 mutex_lock(&stream->device->lock);
266 /* write is allowed when stream is running or has been steup */
267 if (stream->runtime->state != SNDRV_PCM_STATE_SETUP &&
268 stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
269 mutex_unlock(&stream->device->lock);
273 avail = snd_compr_get_avail(stream);
274 pr_debug("avail returned %ld\n", (unsigned long)avail);
275 /* calculate how much we can write to buffer */
279 if (stream->ops->copy) {
280 char __user* cbuf = (char __user*)buf;
281 retval = stream->ops->copy(stream, cbuf, avail);
283 retval = snd_compr_write_data(stream, buf, avail);
286 stream->runtime->total_bytes_available += retval;
288 /* while initiating the stream, write should be called before START
289 * call, so in setup move state */
290 if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
291 stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
292 pr_debug("stream prepared, Houston we are good to go\n");
295 mutex_unlock(&stream->device->lock);
300 static ssize_t snd_compr_read(struct file *f, char __user *buf,
301 size_t count, loff_t *offset)
303 struct snd_compr_file *data = f->private_data;
304 struct snd_compr_stream *stream;
308 if (snd_BUG_ON(!data))
311 stream = &data->stream;
312 mutex_lock(&stream->device->lock);
314 /* read is allowed when stream is running, paused, draining and setup
315 * (yes setup is state which we transition to after stop, so if user
316 * wants to read data after stop we allow that)
318 switch (stream->runtime->state) {
319 case SNDRV_PCM_STATE_OPEN:
320 case SNDRV_PCM_STATE_PREPARED:
321 case SNDRV_PCM_STATE_XRUN:
322 case SNDRV_PCM_STATE_SUSPENDED:
323 case SNDRV_PCM_STATE_DISCONNECTED:
328 avail = snd_compr_get_avail(stream);
329 pr_debug("avail returned %ld\n", (unsigned long)avail);
330 /* calculate how much we can read from buffer */
334 if (stream->ops->copy) {
335 retval = stream->ops->copy(stream, buf, avail);
341 stream->runtime->total_bytes_transferred += retval;
344 mutex_unlock(&stream->device->lock);
348 static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
353 static inline int snd_compr_get_poll(struct snd_compr_stream *stream)
355 if (stream->direction == SND_COMPRESS_PLAYBACK)
356 return POLLOUT | POLLWRNORM;
358 return POLLIN | POLLRDNORM;
361 static unsigned int snd_compr_poll(struct file *f, poll_table *wait)
363 struct snd_compr_file *data = f->private_data;
364 struct snd_compr_stream *stream;
368 if (snd_BUG_ON(!data))
370 stream = &data->stream;
371 if (snd_BUG_ON(!stream))
374 mutex_lock(&stream->device->lock);
375 if (stream->runtime->state == SNDRV_PCM_STATE_PAUSED ||
376 stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
380 poll_wait(f, &stream->runtime->sleep, wait);
382 avail = snd_compr_get_avail(stream);
383 pr_debug("avail is %ld\n", (unsigned long)avail);
384 /* check if we have at least one fragment to fill */
385 switch (stream->runtime->state) {
386 case SNDRV_PCM_STATE_DRAINING:
387 /* stream has been woken up after drain is complete
388 * draining done so set stream state to stopped
390 retval = snd_compr_get_poll(stream);
391 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
393 case SNDRV_PCM_STATE_RUNNING:
394 case SNDRV_PCM_STATE_PREPARED:
395 case SNDRV_PCM_STATE_PAUSED:
396 if (avail >= stream->runtime->fragment_size)
397 retval = snd_compr_get_poll(stream);
400 if (stream->direction == SND_COMPRESS_PLAYBACK)
401 retval = POLLOUT | POLLWRNORM | POLLERR;
403 retval = POLLIN | POLLRDNORM | POLLERR;
407 mutex_unlock(&stream->device->lock);
412 snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
415 struct snd_compr_caps caps;
417 if (!stream->ops->get_caps)
420 memset(&caps, 0, sizeof(caps));
421 retval = stream->ops->get_caps(stream, &caps);
424 if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
431 snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
434 struct snd_compr_codec_caps *caps;
436 if (!stream->ops->get_codec_caps)
439 caps = kzalloc(sizeof(*caps), GFP_KERNEL);
443 retval = stream->ops->get_codec_caps(stream, caps);
446 if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
454 /* revisit this with snd_pcm_preallocate_xxx */
455 static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
456 struct snd_compr_params *params)
458 unsigned int buffer_size;
461 buffer_size = params->buffer.fragment_size * params->buffer.fragments;
462 if (stream->ops->copy) {
464 /* if copy is defined the driver will be required to copy
468 buffer = kmalloc(buffer_size, GFP_KERNEL);
472 stream->runtime->fragment_size = params->buffer.fragment_size;
473 stream->runtime->fragments = params->buffer.fragments;
474 stream->runtime->buffer = buffer;
475 stream->runtime->buffer_size = buffer_size;
479 static int snd_compress_check_input(struct snd_compr_params *params)
481 /* first let's check the buffer parameter's */
482 if (params->buffer.fragment_size == 0 ||
483 params->buffer.fragments > SIZE_MAX / params->buffer.fragment_size)
486 /* now codec parameters */
487 if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
490 if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
493 if (!(params->codec.sample_rate & SNDRV_PCM_RATE_8000_192000))
500 snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
502 struct snd_compr_params *params;
505 if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
507 * we should allow parameter change only when stream has been
508 * opened not in other cases
510 params = kmalloc(sizeof(*params), GFP_KERNEL);
513 if (copy_from_user(params, (void __user *)arg, sizeof(*params))) {
518 retval = snd_compress_check_input(params);
522 retval = snd_compr_allocate_buffer(stream, params);
528 retval = stream->ops->set_params(stream, params);
532 stream->metadata_set = false;
533 stream->next_track = false;
535 if (stream->direction == SND_COMPRESS_PLAYBACK)
536 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
538 stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
548 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
550 struct snd_codec *params;
553 if (!stream->ops->get_params)
556 params = kzalloc(sizeof(*params), GFP_KERNEL);
559 retval = stream->ops->get_params(stream, params);
562 if (copy_to_user((char __user *)arg, params, sizeof(*params)))
571 snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
573 struct snd_compr_metadata metadata;
576 if (!stream->ops->get_metadata)
579 if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
582 retval = stream->ops->get_metadata(stream, &metadata);
586 if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
593 snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
595 struct snd_compr_metadata metadata;
598 if (!stream->ops->set_metadata)
601 * we should allow parameter change only when stream has been
602 * opened not in other cases
604 if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
607 retval = stream->ops->set_metadata(stream, &metadata);
608 stream->metadata_set = true;
614 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
616 struct snd_compr_tstamp tstamp = {0};
619 ret = snd_compr_update_tstamp(stream, &tstamp);
621 ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
622 &tstamp, sizeof(tstamp)) ? -EFAULT : 0;
626 static int snd_compr_pause(struct snd_compr_stream *stream)
630 if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
632 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
634 stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
638 static int snd_compr_resume(struct snd_compr_stream *stream)
642 if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
644 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
646 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
650 static int snd_compr_start(struct snd_compr_stream *stream)
654 if (stream->runtime->state != SNDRV_PCM_STATE_PREPARED)
656 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
658 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
662 static int snd_compr_stop(struct snd_compr_stream *stream)
666 if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
667 stream->runtime->state == SNDRV_PCM_STATE_SETUP)
669 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
671 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
672 wake_up(&stream->runtime->sleep);
673 stream->runtime->total_bytes_available = 0;
674 stream->runtime->total_bytes_transferred = 0;
679 static int snd_compr_drain(struct snd_compr_stream *stream)
683 if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
684 stream->runtime->state == SNDRV_PCM_STATE_SETUP)
686 retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
688 stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
689 wake_up(&stream->runtime->sleep);
694 static int snd_compr_next_track(struct snd_compr_stream *stream)
698 /* only a running stream can transition to next track */
699 if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
702 /* you can signal next track isf this is intended to be a gapless stream
703 * and current track metadata is set
705 if (stream->metadata_set == false)
708 retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
711 stream->metadata_set = false;
712 stream->next_track = true;
716 static int snd_compr_partial_drain(struct snd_compr_stream *stream)
719 if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
720 stream->runtime->state == SNDRV_PCM_STATE_SETUP)
722 /* stream can be drained only when next track has been signalled */
723 if (stream->next_track == false)
726 retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
728 stream->next_track = false;
732 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
734 struct snd_compr_file *data = f->private_data;
735 struct snd_compr_stream *stream;
736 int retval = -ENOTTY;
738 if (snd_BUG_ON(!data))
740 stream = &data->stream;
741 if (snd_BUG_ON(!stream))
743 mutex_lock(&stream->device->lock);
744 switch (_IOC_NR(cmd)) {
745 case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
746 retval = put_user(SNDRV_COMPRESS_VERSION,
747 (int __user *)arg) ? -EFAULT : 0;
749 case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
750 retval = snd_compr_get_caps(stream, arg);
752 case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
753 retval = snd_compr_get_codec_caps(stream, arg);
755 case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
756 retval = snd_compr_set_params(stream, arg);
758 case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
759 retval = snd_compr_get_params(stream, arg);
761 case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
762 retval = snd_compr_set_metadata(stream, arg);
764 case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
765 retval = snd_compr_get_metadata(stream, arg);
767 case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
768 retval = snd_compr_tstamp(stream, arg);
770 case _IOC_NR(SNDRV_COMPRESS_AVAIL):
771 retval = snd_compr_ioctl_avail(stream, arg);
773 case _IOC_NR(SNDRV_COMPRESS_PAUSE):
774 retval = snd_compr_pause(stream);
776 case _IOC_NR(SNDRV_COMPRESS_RESUME):
777 retval = snd_compr_resume(stream);
779 case _IOC_NR(SNDRV_COMPRESS_START):
780 retval = snd_compr_start(stream);
782 case _IOC_NR(SNDRV_COMPRESS_STOP):
783 retval = snd_compr_stop(stream);
785 case _IOC_NR(SNDRV_COMPRESS_DRAIN):
786 retval = snd_compr_drain(stream);
788 case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
789 retval = snd_compr_partial_drain(stream);
791 case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
792 retval = snd_compr_next_track(stream);
796 mutex_unlock(&stream->device->lock);
800 static const struct file_operations snd_compr_file_ops = {
801 .owner = THIS_MODULE,
802 .open = snd_compr_open,
803 .release = snd_compr_free,
804 .write = snd_compr_write,
805 .read = snd_compr_read,
806 .unlocked_ioctl = snd_compr_ioctl,
807 .mmap = snd_compr_mmap,
808 .poll = snd_compr_poll,
811 static int snd_compress_dev_register(struct snd_device *device)
815 struct snd_compr *compr;
817 if (snd_BUG_ON(!device || !device->device_data))
819 compr = device->device_data;
821 sprintf(str, "comprC%iD%i", compr->card->number, compr->device);
822 pr_debug("reg %s for device %s, direction %d\n", str, compr->name,
824 /* register compressed device */
825 ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS, compr->card,
826 compr->device, &snd_compr_file_ops, compr, str);
828 pr_err("snd_register_device failed\n %d", ret);
835 static int snd_compress_dev_disconnect(struct snd_device *device)
837 struct snd_compr *compr;
839 compr = device->device_data;
840 snd_unregister_device(compr->direction, compr->card, compr->device);
845 * snd_compress_new: create new compress device
846 * @card: sound card pointer
847 * @device: device number
848 * @dirn: device direction, should be of type enum snd_compr_direction
849 * @compr: compress device pointer
851 int snd_compress_new(struct snd_card *card, int device,
852 int dirn, struct snd_compr *compr)
854 static struct snd_device_ops ops = {
856 .dev_register = snd_compress_dev_register,
857 .dev_disconnect = snd_compress_dev_disconnect,
861 compr->device = device;
862 compr->direction = dirn;
863 return snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
865 EXPORT_SYMBOL_GPL(snd_compress_new);
867 static int snd_compress_add_device(struct snd_compr *device)
874 /* register the card */
875 ret = snd_card_register(device->card);
881 pr_err("failed with %d\n", ret);
886 static int snd_compress_remove_device(struct snd_compr *device)
888 return snd_card_free(device->card);
892 * snd_compress_register - register compressed device
894 * @device: compressed device to register
896 int snd_compress_register(struct snd_compr *device)
900 if (device->name == NULL || device->dev == NULL || device->ops == NULL)
903 pr_debug("Registering compressed device %s\n", device->name);
904 if (snd_BUG_ON(!device->ops->open))
906 if (snd_BUG_ON(!device->ops->free))
908 if (snd_BUG_ON(!device->ops->set_params))
910 if (snd_BUG_ON(!device->ops->trigger))
913 mutex_init(&device->lock);
915 /* register a compressed card */
916 mutex_lock(&device_mutex);
917 retval = snd_compress_add_device(device);
918 mutex_unlock(&device_mutex);
921 EXPORT_SYMBOL_GPL(snd_compress_register);
923 int snd_compress_deregister(struct snd_compr *device)
925 pr_debug("Removing compressed device %s\n", device->name);
926 mutex_lock(&device_mutex);
927 snd_compress_remove_device(device);
928 mutex_unlock(&device_mutex);
931 EXPORT_SYMBOL_GPL(snd_compress_deregister);
933 static int __init snd_compress_init(void)
938 static void __exit snd_compress_exit(void)
942 module_init(snd_compress_init);
943 module_exit(snd_compress_exit);
945 MODULE_DESCRIPTION("ALSA Compressed offload framework");
946 MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
947 MODULE_LICENSE("GPL v2");