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>
32 #include <linux/mutex.h>
33 #include <linux/poll.h>
34 #include <linux/slab.h>
35 #include <linux/sched.h>
36 #include <linux/uio.h>
37 #include <linux/uaccess.h>
38 #include <linux/module.h>
39 #include <sound/core.h>
40 #include <sound/initval.h>
41 #include <sound/compress_params.h>
42 #include <sound/compress_offload.h>
43 #include <sound/compress_driver.h>
46 * - add substream support for multiple devices in case of
47 * SND_DYNAMIC_MINORS is not used
48 * - Multiple node representation
49 * driver should be able to register multiple nodes
52 static DEFINE_MUTEX(device_mutex);
54 struct snd_compr_file {
56 struct snd_compr_stream stream;
60 * a note on stream states used:
61 * we use follwing states in the compressed core
62 * SNDRV_PCM_STATE_OPEN: When stream has been opened.
63 * SNDRV_PCM_STATE_SETUP: When stream has been initialized. This is done by
64 * calling SNDRV_COMPRESS_SET_PARAMS. running streams will come to this
65 * state at stop by calling SNDRV_COMPRESS_STOP, or at end of drain.
66 * SNDRV_PCM_STATE_RUNNING: When stream has been started and is
67 * decoding/encoding and rendering/capturing data.
68 * SNDRV_PCM_STATE_DRAINING: When stream is draining current data. This is done
69 * by calling SNDRV_COMPRESS_DRAIN.
70 * SNDRV_PCM_STATE_PAUSED: When stream is paused. This is done by calling
71 * SNDRV_COMPRESS_PAUSE. It can be stopped or resumed by calling
72 * SNDRV_COMPRESS_STOP or SNDRV_COMPRESS_RESUME respectively.
74 static int snd_compr_open(struct inode *inode, struct file *f)
76 struct snd_compr *compr;
77 struct snd_compr_file *data;
78 struct snd_compr_runtime *runtime;
79 enum snd_compr_direction dirn;
80 int maj = imajor(inode);
83 if ((f->f_flags & O_ACCMODE) == O_WRONLY)
84 dirn = SND_COMPRESS_PLAYBACK;
85 else if ((f->f_flags & O_ACCMODE) == O_RDONLY)
86 dirn = SND_COMPRESS_CAPTURE;
91 compr = snd_lookup_minor_data(iminor(inode),
92 SNDRV_DEVICE_TYPE_COMPRESS);
97 pr_err("no device data!!!\n");
101 if (dirn != compr->direction) {
102 pr_err("this device doesn't support this direction\n");
103 snd_card_unref(compr->card);
107 data = kzalloc(sizeof(*data), GFP_KERNEL);
109 snd_card_unref(compr->card);
112 data->stream.ops = compr->ops;
113 data->stream.direction = dirn;
114 data->stream.private_data = compr->private_data;
115 data->stream.device = compr;
116 runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
119 snd_card_unref(compr->card);
122 runtime->state = SNDRV_PCM_STATE_OPEN;
123 init_waitqueue_head(&runtime->sleep);
124 data->stream.runtime = runtime;
125 f->private_data = (void *)data;
126 mutex_lock(&compr->lock);
127 ret = compr->ops->open(&data->stream);
128 mutex_unlock(&compr->lock);
133 snd_card_unref(compr->card);
137 static int snd_compr_free(struct inode *inode, struct file *f)
139 struct snd_compr_file *data = f->private_data;
140 data->stream.ops->free(&data->stream);
141 kfree(data->stream.runtime->buffer);
142 kfree(data->stream.runtime);
147 static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
148 struct snd_compr_tstamp *tstamp)
150 if (!stream->ops->pointer)
152 stream->ops->pointer(stream, tstamp);
153 pr_debug("dsp consumed till %d total %d bytes\n",
154 tstamp->byte_offset, tstamp->copied_total);
155 if (stream->direction == SND_COMPRESS_PLAYBACK)
156 stream->runtime->total_bytes_transferred = tstamp->copied_total;
158 stream->runtime->total_bytes_available = tstamp->copied_total;
162 static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
163 struct snd_compr_avail *avail)
165 memset(avail, 0, sizeof(*avail));
166 snd_compr_update_tstamp(stream, &avail->tstamp);
167 /* Still need to return avail even if tstamp can't be filled in */
169 if (stream->runtime->total_bytes_available == 0 &&
170 stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
171 stream->direction == SND_COMPRESS_PLAYBACK) {
172 pr_debug("detected init and someone forgot to do a write\n");
173 return stream->runtime->buffer_size;
175 pr_debug("app wrote %lld, DSP consumed %lld\n",
176 stream->runtime->total_bytes_available,
177 stream->runtime->total_bytes_transferred);
178 if (stream->runtime->total_bytes_available ==
179 stream->runtime->total_bytes_transferred) {
180 if (stream->direction == SND_COMPRESS_PLAYBACK) {
181 pr_debug("both pointers are same, returning full avail\n");
182 return stream->runtime->buffer_size;
184 pr_debug("both pointers are same, returning no avail\n");
189 avail->avail = stream->runtime->total_bytes_available -
190 stream->runtime->total_bytes_transferred;
191 if (stream->direction == SND_COMPRESS_PLAYBACK)
192 avail->avail = stream->runtime->buffer_size - avail->avail;
194 pr_debug("ret avail as %lld\n", avail->avail);
198 static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
200 struct snd_compr_avail avail;
202 return snd_compr_calc_avail(stream, &avail);
206 snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
208 struct snd_compr_avail ioctl_avail;
211 avail = snd_compr_calc_avail(stream, &ioctl_avail);
212 ioctl_avail.avail = avail;
214 if (copy_to_user((__u64 __user *)arg,
215 &ioctl_avail, sizeof(ioctl_avail)))
220 static int snd_compr_write_data(struct snd_compr_stream *stream,
221 const char __user *buf, size_t count)
225 struct snd_compr_runtime *runtime = stream->runtime;
227 dstn = runtime->buffer + runtime->app_pointer;
228 pr_debug("copying %ld at %lld\n",
229 (unsigned long)count, runtime->app_pointer);
230 if (count < runtime->buffer_size - runtime->app_pointer) {
231 if (copy_from_user(dstn, buf, count))
233 runtime->app_pointer += count;
235 copy = runtime->buffer_size - runtime->app_pointer;
236 if (copy_from_user(dstn, buf, copy))
238 if (copy_from_user(runtime->buffer, buf + copy, count - copy))
240 runtime->app_pointer = count - copy;
242 /* if DSP cares, let it know data has been written */
243 if (stream->ops->ack)
244 stream->ops->ack(stream, count);
248 static ssize_t snd_compr_write(struct file *f, const char __user *buf,
249 size_t count, loff_t *offset)
251 struct snd_compr_file *data = f->private_data;
252 struct snd_compr_stream *stream;
256 if (snd_BUG_ON(!data))
259 stream = &data->stream;
260 mutex_lock(&stream->device->lock);
261 /* write is allowed when stream is running or has been steup */
262 if (stream->runtime->state != SNDRV_PCM_STATE_SETUP &&
263 stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
264 mutex_unlock(&stream->device->lock);
268 avail = snd_compr_get_avail(stream);
269 pr_debug("avail returned %ld\n", (unsigned long)avail);
270 /* calculate how much we can write to buffer */
274 if (stream->ops->copy) {
275 char __user* cbuf = (char __user*)buf;
276 retval = stream->ops->copy(stream, cbuf, avail);
278 retval = snd_compr_write_data(stream, buf, avail);
281 stream->runtime->total_bytes_available += retval;
283 /* while initiating the stream, write should be called before START
284 * call, so in setup move state */
285 if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
286 stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
287 pr_debug("stream prepared, Houston we are good to go\n");
290 mutex_unlock(&stream->device->lock);
295 static ssize_t snd_compr_read(struct file *f, char __user *buf,
296 size_t count, loff_t *offset)
298 struct snd_compr_file *data = f->private_data;
299 struct snd_compr_stream *stream;
303 if (snd_BUG_ON(!data))
306 stream = &data->stream;
307 mutex_lock(&stream->device->lock);
309 /* read is allowed when stream is running */
310 if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
315 avail = snd_compr_get_avail(stream);
316 pr_debug("avail returned %ld\n", (unsigned long)avail);
317 /* calculate how much we can read from buffer */
321 if (stream->ops->copy) {
322 retval = stream->ops->copy(stream, buf, avail);
328 stream->runtime->total_bytes_transferred += retval;
331 mutex_unlock(&stream->device->lock);
335 static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
340 static inline int snd_compr_get_poll(struct snd_compr_stream *stream)
342 if (stream->direction == SND_COMPRESS_PLAYBACK)
343 return POLLOUT | POLLWRNORM;
345 return POLLIN | POLLRDNORM;
348 static unsigned int snd_compr_poll(struct file *f, poll_table *wait)
350 struct snd_compr_file *data = f->private_data;
351 struct snd_compr_stream *stream;
355 if (snd_BUG_ON(!data))
357 stream = &data->stream;
358 if (snd_BUG_ON(!stream))
361 mutex_lock(&stream->device->lock);
362 if (stream->runtime->state == SNDRV_PCM_STATE_PAUSED ||
363 stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
367 poll_wait(f, &stream->runtime->sleep, wait);
369 avail = snd_compr_get_avail(stream);
370 pr_debug("avail is %ld\n", (unsigned long)avail);
371 /* check if we have at least one fragment to fill */
372 switch (stream->runtime->state) {
373 case SNDRV_PCM_STATE_DRAINING:
374 /* stream has been woken up after drain is complete
375 * draining done so set stream state to stopped
377 retval = snd_compr_get_poll(stream);
378 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
380 case SNDRV_PCM_STATE_RUNNING:
381 case SNDRV_PCM_STATE_PREPARED:
382 case SNDRV_PCM_STATE_PAUSED:
383 if (avail >= stream->runtime->fragment_size)
384 retval = snd_compr_get_poll(stream);
387 if (stream->direction == SND_COMPRESS_PLAYBACK)
388 retval = POLLOUT | POLLWRNORM | POLLERR;
390 retval = POLLIN | POLLRDNORM | POLLERR;
394 mutex_unlock(&stream->device->lock);
399 snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
402 struct snd_compr_caps caps;
404 if (!stream->ops->get_caps)
407 retval = stream->ops->get_caps(stream, &caps);
410 if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
417 snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
420 struct snd_compr_codec_caps *caps;
422 if (!stream->ops->get_codec_caps)
425 caps = kmalloc(sizeof(*caps), GFP_KERNEL);
429 retval = stream->ops->get_codec_caps(stream, caps);
432 if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
440 /* revisit this with snd_pcm_preallocate_xxx */
441 static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
442 struct snd_compr_params *params)
444 unsigned int buffer_size;
447 buffer_size = params->buffer.fragment_size * params->buffer.fragments;
448 if (stream->ops->copy) {
450 /* if copy is defined the driver will be required to copy
454 buffer = kmalloc(buffer_size, GFP_KERNEL);
458 stream->runtime->fragment_size = params->buffer.fragment_size;
459 stream->runtime->fragments = params->buffer.fragments;
460 stream->runtime->buffer = buffer;
461 stream->runtime->buffer_size = buffer_size;
465 static int snd_compress_check_input(struct snd_compr_params *params)
467 /* first let's check the buffer parameter's */
468 if (params->buffer.fragment_size == 0 ||
469 params->buffer.fragments > SIZE_MAX / params->buffer.fragment_size)
472 /* now codec parameters */
473 if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
476 if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
479 if (!(params->codec.sample_rate & SNDRV_PCM_RATE_8000_192000))
486 snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
488 struct snd_compr_params *params;
491 if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
493 * we should allow parameter change only when stream has been
494 * opened not in other cases
496 params = kmalloc(sizeof(*params), GFP_KERNEL);
499 if (copy_from_user(params, (void __user *)arg, sizeof(*params))) {
504 retval = snd_compress_check_input(params);
508 retval = snd_compr_allocate_buffer(stream, params);
514 retval = stream->ops->set_params(stream, params);
518 stream->metadata_set = false;
519 stream->next_track = false;
521 if (stream->direction == SND_COMPRESS_PLAYBACK)
522 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
524 stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
534 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
536 struct snd_codec *params;
539 if (!stream->ops->get_params)
542 params = kmalloc(sizeof(*params), GFP_KERNEL);
545 retval = stream->ops->get_params(stream, params);
548 if (copy_to_user((char __user *)arg, params, sizeof(*params)))
557 snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
559 struct snd_compr_metadata metadata;
562 if (!stream->ops->get_metadata)
565 if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
568 retval = stream->ops->get_metadata(stream, &metadata);
572 if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
579 snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
581 struct snd_compr_metadata metadata;
584 if (!stream->ops->set_metadata)
587 * we should allow parameter change only when stream has been
588 * opened not in other cases
590 if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
593 retval = stream->ops->set_metadata(stream, &metadata);
594 stream->metadata_set = true;
600 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
602 struct snd_compr_tstamp tstamp = {0};
605 ret = snd_compr_update_tstamp(stream, &tstamp);
607 ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
608 &tstamp, sizeof(tstamp)) ? -EFAULT : 0;
612 static int snd_compr_pause(struct snd_compr_stream *stream)
616 if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
618 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
620 stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
624 static int snd_compr_resume(struct snd_compr_stream *stream)
628 if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
630 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
632 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
636 static int snd_compr_start(struct snd_compr_stream *stream)
640 if (stream->runtime->state != SNDRV_PCM_STATE_PREPARED)
642 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
644 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
648 static int snd_compr_stop(struct snd_compr_stream *stream)
652 if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
653 stream->runtime->state == SNDRV_PCM_STATE_SETUP)
655 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
657 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
658 wake_up(&stream->runtime->sleep);
659 stream->runtime->app_pointer = 0;
660 stream->runtime->total_bytes_available = 0;
661 stream->runtime->total_bytes_transferred = 0;
666 static int snd_compr_drain(struct snd_compr_stream *stream)
670 if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
671 stream->runtime->state == SNDRV_PCM_STATE_SETUP)
673 retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
675 stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
676 wake_up(&stream->runtime->sleep);
681 static int snd_compr_next_track(struct snd_compr_stream *stream)
685 /* only a running stream can transition to next track */
686 if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
689 /* you can signal next track isf this is intended to be a gapless stream
690 * and current track metadata is set
692 if (stream->metadata_set == false)
695 retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
698 stream->metadata_set = false;
699 stream->next_track = true;
703 static int snd_compr_partial_drain(struct snd_compr_stream *stream)
706 if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
707 stream->runtime->state == SNDRV_PCM_STATE_SETUP)
709 /* stream can be drained only when next track has been signalled */
710 if (stream->next_track == false)
713 retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
715 stream->next_track = false;
719 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
721 struct snd_compr_file *data = f->private_data;
722 struct snd_compr_stream *stream;
723 int retval = -ENOTTY;
725 if (snd_BUG_ON(!data))
727 stream = &data->stream;
728 if (snd_BUG_ON(!stream))
730 mutex_lock(&stream->device->lock);
731 switch (_IOC_NR(cmd)) {
732 case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
733 put_user(SNDRV_COMPRESS_VERSION,
734 (int __user *)arg) ? -EFAULT : 0;
736 case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
737 retval = snd_compr_get_caps(stream, arg);
739 case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
740 retval = snd_compr_get_codec_caps(stream, arg);
742 case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
743 retval = snd_compr_set_params(stream, arg);
745 case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
746 retval = snd_compr_get_params(stream, arg);
748 case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
749 retval = snd_compr_set_metadata(stream, arg);
751 case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
752 retval = snd_compr_get_metadata(stream, arg);
754 case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
755 retval = snd_compr_tstamp(stream, arg);
757 case _IOC_NR(SNDRV_COMPRESS_AVAIL):
758 retval = snd_compr_ioctl_avail(stream, arg);
760 case _IOC_NR(SNDRV_COMPRESS_PAUSE):
761 retval = snd_compr_pause(stream);
763 case _IOC_NR(SNDRV_COMPRESS_RESUME):
764 retval = snd_compr_resume(stream);
766 case _IOC_NR(SNDRV_COMPRESS_START):
767 retval = snd_compr_start(stream);
769 case _IOC_NR(SNDRV_COMPRESS_STOP):
770 retval = snd_compr_stop(stream);
772 case _IOC_NR(SNDRV_COMPRESS_DRAIN):
773 retval = snd_compr_drain(stream);
775 case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
776 retval = snd_compr_partial_drain(stream);
778 case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
779 retval = snd_compr_next_track(stream);
783 mutex_unlock(&stream->device->lock);
787 static const struct file_operations snd_compr_file_ops = {
788 .owner = THIS_MODULE,
789 .open = snd_compr_open,
790 .release = snd_compr_free,
791 .write = snd_compr_write,
792 .read = snd_compr_read,
793 .unlocked_ioctl = snd_compr_ioctl,
794 .mmap = snd_compr_mmap,
795 .poll = snd_compr_poll,
798 static int snd_compress_dev_register(struct snd_device *device)
802 struct snd_compr *compr;
804 if (snd_BUG_ON(!device || !device->device_data))
806 compr = device->device_data;
808 sprintf(str, "comprC%iD%i", compr->card->number, compr->device);
809 pr_debug("reg %s for device %s, direction %d\n", str, compr->name,
811 /* register compressed device */
812 ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS, compr->card,
813 compr->device, &snd_compr_file_ops, compr, str);
815 pr_err("snd_register_device failed\n %d", ret);
822 static int snd_compress_dev_disconnect(struct snd_device *device)
824 struct snd_compr *compr;
826 compr = device->device_data;
827 snd_unregister_device(compr->direction, compr->card, compr->device);
832 * snd_compress_new: create new compress device
833 * @card: sound card pointer
834 * @device: device number
835 * @dirn: device direction, should be of type enum snd_compr_direction
836 * @compr: compress device pointer
838 int snd_compress_new(struct snd_card *card, int device,
839 int dirn, struct snd_compr *compr)
841 static struct snd_device_ops ops = {
843 .dev_register = snd_compress_dev_register,
844 .dev_disconnect = snd_compress_dev_disconnect,
848 compr->device = device;
849 compr->direction = dirn;
850 return snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
852 EXPORT_SYMBOL_GPL(snd_compress_new);
854 static int snd_compress_add_device(struct snd_compr *device)
861 /* register the card */
862 ret = snd_card_register(device->card);
868 pr_err("failed with %d\n", ret);
873 static int snd_compress_remove_device(struct snd_compr *device)
875 return snd_card_free(device->card);
879 * snd_compress_register - register compressed device
881 * @device: compressed device to register
883 int snd_compress_register(struct snd_compr *device)
887 if (device->name == NULL || device->dev == NULL || device->ops == NULL)
890 pr_debug("Registering compressed device %s\n", device->name);
891 if (snd_BUG_ON(!device->ops->open))
893 if (snd_BUG_ON(!device->ops->free))
895 if (snd_BUG_ON(!device->ops->set_params))
897 if (snd_BUG_ON(!device->ops->trigger))
900 mutex_init(&device->lock);
902 /* register a compressed card */
903 mutex_lock(&device_mutex);
904 retval = snd_compress_add_device(device);
905 mutex_unlock(&device_mutex);
908 EXPORT_SYMBOL_GPL(snd_compress_register);
910 int snd_compress_deregister(struct snd_compr *device)
912 pr_debug("Removing compressed device %s\n", device->name);
913 mutex_lock(&device_mutex);
914 snd_compress_remove_device(device);
915 mutex_unlock(&device_mutex);
918 EXPORT_SYMBOL_GPL(snd_compress_deregister);
920 static int __init snd_compress_init(void)
925 static void __exit snd_compress_exit(void)
929 module_init(snd_compress_init);
930 module_exit(snd_compress_exit);
932 MODULE_DESCRIPTION("ALSA Compressed offload framework");
933 MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
934 MODULE_LICENSE("GPL v2");