Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci
[linux-2.6.git] / sound / core / compress_offload.c
bloba68aed7fce0205462ce08183f560015eeb0060cb
1 /*
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>
29 #include <linux/fs.h>
30 #include <linux/list.h>
31 #include <linux/mm.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>
45 /* TODO:
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 {
55 unsigned long caps;
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);
81 int ret;
83 if (f->f_flags & O_WRONLY)
84 dirn = SND_COMPRESS_PLAYBACK;
85 else if (f->f_flags & O_RDONLY)
86 dirn = SND_COMPRESS_CAPTURE;
87 else {
88 pr_err("invalid direction\n");
89 return -EINVAL;
92 if (maj == snd_major)
93 compr = snd_lookup_minor_data(iminor(inode),
94 SNDRV_DEVICE_TYPE_COMPRESS);
95 else
96 return -EBADFD;
98 if (compr == NULL) {
99 pr_err("no device data!!!\n");
100 return -ENODEV;
103 if (dirn != compr->direction) {
104 pr_err("this device doesn't support this direction\n");
105 return -EINVAL;
108 data = kzalloc(sizeof(*data), GFP_KERNEL);
109 if (!data)
110 return -ENOMEM;
111 data->stream.ops = compr->ops;
112 data->stream.direction = dirn;
113 data->stream.private_data = compr->private_data;
114 data->stream.device = compr;
115 runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
116 if (!runtime) {
117 kfree(data);
118 return -ENOMEM;
120 runtime->state = SNDRV_PCM_STATE_OPEN;
121 init_waitqueue_head(&runtime->sleep);
122 data->stream.runtime = runtime;
123 f->private_data = (void *)data;
124 mutex_lock(&compr->lock);
125 ret = compr->ops->open(&data->stream);
126 mutex_unlock(&compr->lock);
127 if (ret) {
128 kfree(runtime);
129 kfree(data);
131 return ret;
134 static int snd_compr_free(struct inode *inode, struct file *f)
136 struct snd_compr_file *data = f->private_data;
137 data->stream.ops->free(&data->stream);
138 kfree(data->stream.runtime->buffer);
139 kfree(data->stream.runtime);
140 kfree(data);
141 return 0;
144 static void snd_compr_update_tstamp(struct snd_compr_stream *stream,
145 struct snd_compr_tstamp *tstamp)
147 if (!stream->ops->pointer)
148 return;
149 stream->ops->pointer(stream, tstamp);
150 pr_debug("dsp consumed till %d total %d bytes\n",
151 tstamp->byte_offset, tstamp->copied_total);
152 stream->runtime->hw_pointer = tstamp->byte_offset;
153 stream->runtime->total_bytes_transferred = tstamp->copied_total;
156 static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
157 struct snd_compr_avail *avail)
159 long avail_calc; /*this needs to be signed variable */
161 snd_compr_update_tstamp(stream, &avail->tstamp);
163 /* FIXME: This needs to be different for capture stream,
164 available is # of compressed data, for playback it's
165 remainder of buffer */
167 if (stream->runtime->total_bytes_available == 0 &&
168 stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
169 pr_debug("detected init and someone forgot to do a write\n");
170 return stream->runtime->buffer_size;
172 pr_debug("app wrote %lld, DSP consumed %lld\n",
173 stream->runtime->total_bytes_available,
174 stream->runtime->total_bytes_transferred);
175 if (stream->runtime->total_bytes_available ==
176 stream->runtime->total_bytes_transferred) {
177 pr_debug("both pointers are same, returning full avail\n");
178 return stream->runtime->buffer_size;
181 /* FIXME: this routine isn't consistent, in one test we use
182 * cumulative values and in the other byte offsets. Do we
183 * really need the byte offsets if the cumulative values have
184 * been updated? In the PCM interface app_ptr and hw_ptr are
185 * already cumulative */
187 avail_calc = stream->runtime->buffer_size -
188 (stream->runtime->app_pointer - stream->runtime->hw_pointer);
189 pr_debug("calc avail as %ld, app_ptr %lld, hw+ptr %lld\n", avail_calc,
190 stream->runtime->app_pointer,
191 stream->runtime->hw_pointer);
192 if (avail_calc >= stream->runtime->buffer_size)
193 avail_calc -= stream->runtime->buffer_size;
194 pr_debug("ret avail as %ld\n", avail_calc);
195 avail->avail = avail_calc;
196 return avail_calc;
199 static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
201 struct snd_compr_avail avail;
203 return snd_compr_calc_avail(stream, &avail);
206 static int
207 snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
209 struct snd_compr_avail ioctl_avail;
210 size_t avail;
212 avail = snd_compr_calc_avail(stream, &ioctl_avail);
213 ioctl_avail.avail = avail;
215 if (copy_to_user((__u64 __user *)arg,
216 &ioctl_avail, sizeof(ioctl_avail)))
217 return -EFAULT;
218 return 0;
221 static int snd_compr_write_data(struct snd_compr_stream *stream,
222 const char __user *buf, size_t count)
224 void *dstn;
225 size_t copy;
226 struct snd_compr_runtime *runtime = stream->runtime;
228 dstn = runtime->buffer + runtime->app_pointer;
229 pr_debug("copying %ld at %lld\n",
230 (unsigned long)count, runtime->app_pointer);
231 if (count < runtime->buffer_size - runtime->app_pointer) {
232 if (copy_from_user(dstn, buf, count))
233 return -EFAULT;
234 runtime->app_pointer += count;
235 } else {
236 copy = runtime->buffer_size - runtime->app_pointer;
237 if (copy_from_user(dstn, buf, copy))
238 return -EFAULT;
239 if (copy_from_user(runtime->buffer, buf + copy, count - copy))
240 return -EFAULT;
241 runtime->app_pointer = count - copy;
243 /* if DSP cares, let it know data has been written */
244 if (stream->ops->ack)
245 stream->ops->ack(stream, count);
246 return count;
249 static ssize_t snd_compr_write(struct file *f, const char __user *buf,
250 size_t count, loff_t *offset)
252 struct snd_compr_file *data = f->private_data;
253 struct snd_compr_stream *stream;
254 size_t avail;
255 int retval;
257 if (snd_BUG_ON(!data))
258 return -EFAULT;
260 stream = &data->stream;
261 mutex_lock(&stream->device->lock);
262 /* write is allowed when stream is running or has been steup */
263 if (stream->runtime->state != SNDRV_PCM_STATE_SETUP &&
264 stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
265 mutex_unlock(&stream->device->lock);
266 return -EBADFD;
269 avail = snd_compr_get_avail(stream);
270 pr_debug("avail returned %ld\n", (unsigned long)avail);
271 /* calculate how much we can write to buffer */
272 if (avail > count)
273 avail = count;
275 if (stream->ops->copy)
276 retval = stream->ops->copy(stream, buf, avail);
277 else
278 retval = snd_compr_write_data(stream, buf, avail);
279 if (retval > 0)
280 stream->runtime->total_bytes_available += retval;
282 /* while initiating the stream, write should be called before START
283 * call, so in setup move state */
284 if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
285 stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
286 pr_debug("stream prepared, Houston we are good to go\n");
289 mutex_unlock(&stream->device->lock);
290 return retval;
294 static ssize_t snd_compr_read(struct file *f, char __user *buf,
295 size_t count, loff_t *offset)
297 return -ENXIO;
300 static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
302 return -ENXIO;
305 static inline int snd_compr_get_poll(struct snd_compr_stream *stream)
307 if (stream->direction == SND_COMPRESS_PLAYBACK)
308 return POLLOUT | POLLWRNORM;
309 else
310 return POLLIN | POLLRDNORM;
313 static unsigned int snd_compr_poll(struct file *f, poll_table *wait)
315 struct snd_compr_file *data = f->private_data;
316 struct snd_compr_stream *stream;
317 size_t avail;
318 int retval = 0;
320 if (snd_BUG_ON(!data))
321 return -EFAULT;
322 stream = &data->stream;
323 if (snd_BUG_ON(!stream))
324 return -EFAULT;
326 mutex_lock(&stream->device->lock);
327 if (stream->runtime->state == SNDRV_PCM_STATE_PAUSED ||
328 stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
329 retval = -EBADFD;
330 goto out;
332 poll_wait(f, &stream->runtime->sleep, wait);
334 avail = snd_compr_get_avail(stream);
335 pr_debug("avail is %ld\n", (unsigned long)avail);
336 /* check if we have at least one fragment to fill */
337 switch (stream->runtime->state) {
338 case SNDRV_PCM_STATE_DRAINING:
339 /* stream has been woken up after drain is complete
340 * draining done so set stream state to stopped
342 retval = snd_compr_get_poll(stream);
343 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
344 break;
345 case SNDRV_PCM_STATE_RUNNING:
346 case SNDRV_PCM_STATE_PREPARED:
347 case SNDRV_PCM_STATE_PAUSED:
348 if (avail >= stream->runtime->fragment_size)
349 retval = snd_compr_get_poll(stream);
350 break;
351 default:
352 if (stream->direction == SND_COMPRESS_PLAYBACK)
353 retval = POLLOUT | POLLWRNORM | POLLERR;
354 else
355 retval = POLLIN | POLLRDNORM | POLLERR;
356 break;
358 out:
359 mutex_unlock(&stream->device->lock);
360 return retval;
363 static int
364 snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
366 int retval;
367 struct snd_compr_caps caps;
369 if (!stream->ops->get_caps)
370 return -ENXIO;
372 retval = stream->ops->get_caps(stream, &caps);
373 if (retval)
374 goto out;
375 if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
376 retval = -EFAULT;
377 out:
378 return retval;
381 static int
382 snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
384 int retval;
385 struct snd_compr_codec_caps *caps;
387 if (!stream->ops->get_codec_caps)
388 return -ENXIO;
390 caps = kmalloc(sizeof(*caps), GFP_KERNEL);
391 if (!caps)
392 return -ENOMEM;
394 retval = stream->ops->get_codec_caps(stream, caps);
395 if (retval)
396 goto out;
397 if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
398 retval = -EFAULT;
400 out:
401 kfree(caps);
402 return retval;
405 /* revisit this with snd_pcm_preallocate_xxx */
406 static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
407 struct snd_compr_params *params)
409 unsigned int buffer_size;
410 void *buffer;
412 buffer_size = params->buffer.fragment_size * params->buffer.fragments;
413 if (stream->ops->copy) {
414 buffer = NULL;
415 /* if copy is defined the driver will be required to copy
416 * the data from core
418 } else {
419 buffer = kmalloc(buffer_size, GFP_KERNEL);
420 if (!buffer)
421 return -ENOMEM;
423 stream->runtime->fragment_size = params->buffer.fragment_size;
424 stream->runtime->fragments = params->buffer.fragments;
425 stream->runtime->buffer = buffer;
426 stream->runtime->buffer_size = buffer_size;
427 return 0;
430 static int
431 snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
433 struct snd_compr_params *params;
434 int retval;
436 if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
438 * we should allow parameter change only when stream has been
439 * opened not in other cases
441 params = kmalloc(sizeof(*params), GFP_KERNEL);
442 if (!params)
443 return -ENOMEM;
444 if (copy_from_user(params, (void __user *)arg, sizeof(*params))) {
445 retval = -EFAULT;
446 goto out;
448 retval = snd_compr_allocate_buffer(stream, params);
449 if (retval) {
450 retval = -ENOMEM;
451 goto out;
453 retval = stream->ops->set_params(stream, params);
454 if (retval)
455 goto out;
456 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
457 } else {
458 return -EPERM;
460 out:
461 kfree(params);
462 return retval;
465 static int
466 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
468 struct snd_codec *params;
469 int retval;
471 if (!stream->ops->get_params)
472 return -EBADFD;
474 params = kmalloc(sizeof(*params), GFP_KERNEL);
475 if (!params)
476 return -ENOMEM;
477 retval = stream->ops->get_params(stream, params);
478 if (retval)
479 goto out;
480 if (copy_to_user((char __user *)arg, params, sizeof(*params)))
481 retval = -EFAULT;
483 out:
484 kfree(params);
485 return retval;
488 static inline int
489 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
491 struct snd_compr_tstamp tstamp;
493 snd_compr_update_tstamp(stream, &tstamp);
494 return copy_to_user((struct snd_compr_tstamp __user *)arg,
495 &tstamp, sizeof(tstamp)) ? -EFAULT : 0;
498 static int snd_compr_pause(struct snd_compr_stream *stream)
500 int retval;
502 if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
503 return -EPERM;
504 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
505 if (!retval) {
506 stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
507 wake_up(&stream->runtime->sleep);
509 return retval;
512 static int snd_compr_resume(struct snd_compr_stream *stream)
514 int retval;
516 if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
517 return -EPERM;
518 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
519 if (!retval)
520 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
521 return retval;
524 static int snd_compr_start(struct snd_compr_stream *stream)
526 int retval;
528 if (stream->runtime->state != SNDRV_PCM_STATE_PREPARED)
529 return -EPERM;
530 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
531 if (!retval)
532 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
533 return retval;
536 static int snd_compr_stop(struct snd_compr_stream *stream)
538 int retval;
540 if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
541 stream->runtime->state == SNDRV_PCM_STATE_SETUP)
542 return -EPERM;
543 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
544 if (!retval) {
545 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
546 wake_up(&stream->runtime->sleep);
548 return retval;
551 static int snd_compr_drain(struct snd_compr_stream *stream)
553 int retval;
555 if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
556 stream->runtime->state == SNDRV_PCM_STATE_SETUP)
557 return -EPERM;
558 retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
559 if (!retval) {
560 stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
561 wake_up(&stream->runtime->sleep);
563 return retval;
566 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
568 struct snd_compr_file *data = f->private_data;
569 struct snd_compr_stream *stream;
570 int retval = -ENOTTY;
572 if (snd_BUG_ON(!data))
573 return -EFAULT;
574 stream = &data->stream;
575 if (snd_BUG_ON(!stream))
576 return -EFAULT;
577 mutex_lock(&stream->device->lock);
578 switch (_IOC_NR(cmd)) {
579 case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
580 put_user(SNDRV_COMPRESS_VERSION,
581 (int __user *)arg) ? -EFAULT : 0;
582 break;
583 case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
584 retval = snd_compr_get_caps(stream, arg);
585 break;
586 case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
587 retval = snd_compr_get_codec_caps(stream, arg);
588 break;
589 case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
590 retval = snd_compr_set_params(stream, arg);
591 break;
592 case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
593 retval = snd_compr_get_params(stream, arg);
594 break;
595 case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
596 retval = snd_compr_tstamp(stream, arg);
597 break;
598 case _IOC_NR(SNDRV_COMPRESS_AVAIL):
599 retval = snd_compr_ioctl_avail(stream, arg);
600 break;
601 case _IOC_NR(SNDRV_COMPRESS_PAUSE):
602 retval = snd_compr_pause(stream);
603 break;
604 case _IOC_NR(SNDRV_COMPRESS_RESUME):
605 retval = snd_compr_resume(stream);
606 break;
607 case _IOC_NR(SNDRV_COMPRESS_START):
608 retval = snd_compr_start(stream);
609 break;
610 case _IOC_NR(SNDRV_COMPRESS_STOP):
611 retval = snd_compr_stop(stream);
612 break;
613 case _IOC_NR(SNDRV_COMPRESS_DRAIN):
614 retval = snd_compr_drain(stream);
615 break;
617 mutex_unlock(&stream->device->lock);
618 return retval;
621 static const struct file_operations snd_compr_file_ops = {
622 .owner = THIS_MODULE,
623 .open = snd_compr_open,
624 .release = snd_compr_free,
625 .write = snd_compr_write,
626 .read = snd_compr_read,
627 .unlocked_ioctl = snd_compr_ioctl,
628 .mmap = snd_compr_mmap,
629 .poll = snd_compr_poll,
632 static int snd_compress_dev_register(struct snd_device *device)
634 int ret = -EINVAL;
635 char str[16];
636 struct snd_compr *compr;
638 if (snd_BUG_ON(!device || !device->device_data))
639 return -EBADFD;
640 compr = device->device_data;
642 sprintf(str, "comprC%iD%i", compr->card->number, compr->device);
643 pr_debug("reg %s for device %s, direction %d\n", str, compr->name,
644 compr->direction);
645 /* register compressed device */
646 ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS, compr->card,
647 compr->device, &snd_compr_file_ops, compr, str);
648 if (ret < 0) {
649 pr_err("snd_register_device failed\n %d", ret);
650 return ret;
652 return ret;
656 static int snd_compress_dev_disconnect(struct snd_device *device)
658 struct snd_compr *compr;
660 compr = device->device_data;
661 snd_unregister_device(compr->direction, compr->card, compr->device);
662 return 0;
666 * snd_compress_new: create new compress device
667 * @card: sound card pointer
668 * @device: device number
669 * @dirn: device direction, should be of type enum snd_compr_direction
670 * @compr: compress device pointer
672 int snd_compress_new(struct snd_card *card, int device,
673 int dirn, struct snd_compr *compr)
675 static struct snd_device_ops ops = {
676 .dev_free = NULL,
677 .dev_register = snd_compress_dev_register,
678 .dev_disconnect = snd_compress_dev_disconnect,
681 compr->card = card;
682 compr->device = device;
683 compr->direction = dirn;
684 return snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
686 EXPORT_SYMBOL_GPL(snd_compress_new);
688 static int snd_compress_add_device(struct snd_compr *device)
690 int ret;
692 if (!device->card)
693 return -EINVAL;
695 /* register the card */
696 ret = snd_card_register(device->card);
697 if (ret)
698 goto out;
699 return 0;
701 out:
702 pr_err("failed with %d\n", ret);
703 return ret;
707 static int snd_compress_remove_device(struct snd_compr *device)
709 return snd_card_free(device->card);
713 * snd_compress_register - register compressed device
715 * @device: compressed device to register
717 int snd_compress_register(struct snd_compr *device)
719 int retval;
721 if (device->name == NULL || device->dev == NULL || device->ops == NULL)
722 return -EINVAL;
724 pr_debug("Registering compressed device %s\n", device->name);
725 if (snd_BUG_ON(!device->ops->open))
726 return -EINVAL;
727 if (snd_BUG_ON(!device->ops->free))
728 return -EINVAL;
729 if (snd_BUG_ON(!device->ops->set_params))
730 return -EINVAL;
731 if (snd_BUG_ON(!device->ops->trigger))
732 return -EINVAL;
734 mutex_init(&device->lock);
736 /* register a compressed card */
737 mutex_lock(&device_mutex);
738 retval = snd_compress_add_device(device);
739 mutex_unlock(&device_mutex);
740 return retval;
742 EXPORT_SYMBOL_GPL(snd_compress_register);
744 int snd_compress_deregister(struct snd_compr *device)
746 pr_debug("Removing compressed device %s\n", device->name);
747 mutex_lock(&device_mutex);
748 snd_compress_remove_device(device);
749 mutex_unlock(&device_mutex);
750 return 0;
752 EXPORT_SYMBOL_GPL(snd_compress_deregister);
754 static int __init snd_compress_init(void)
756 return 0;
759 static void __exit snd_compress_exit(void)
763 module_init(snd_compress_init);
764 module_exit(snd_compress_exit);
766 MODULE_DESCRIPTION("ALSA Compressed offload framework");
767 MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
768 MODULE_LICENSE("GPL v2");