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v3.15
  1/*
  2 *  compress_core.c - compress offload core
  3 *
  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 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  8 *
  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.
 12 *
 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.
 17 *
 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.
 21 *
 22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 23 *
 24 */
 25#define FORMAT(fmt) "%s: %d: " fmt, __func__, __LINE__
 26#define pr_fmt(fmt) KBUILD_MODNAME ": " FORMAT(fmt)
 27
 28#include <linux/file.h>
 29#include <linux/fs.h>
 30#include <linux/list.h>
 31#include <linux/math64.h>
 32#include <linux/mm.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>
 46
 
 
 
 
 
 
 
 47/* TODO:
 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
 52 */
 53
 54static DEFINE_MUTEX(device_mutex);
 55
 56struct snd_compr_file {
 57	unsigned long caps;
 58	struct snd_compr_stream stream;
 59};
 60
 61/*
 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.
 75 */
 76static int snd_compr_open(struct inode *inode, struct file *f)
 77{
 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);
 83	int ret;
 84
 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;
 89	else
 90		return -EINVAL;
 91
 92	if (maj == snd_major)
 93		compr = snd_lookup_minor_data(iminor(inode),
 94					SNDRV_DEVICE_TYPE_COMPRESS);
 95	else
 96		return -EBADFD;
 97
 98	if (compr == NULL) {
 99		pr_err("no device data!!!\n");
100		return -ENODEV;
101	}
102
103	if (dirn != compr->direction) {
104		pr_err("this device doesn't support this direction\n");
105		snd_card_unref(compr->card);
106		return -EINVAL;
107	}
108
109	data = kzalloc(sizeof(*data), GFP_KERNEL);
110	if (!data) {
111		snd_card_unref(compr->card);
112		return -ENOMEM;
113	}
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);
119	if (!runtime) {
120		kfree(data);
121		snd_card_unref(compr->card);
122		return -ENOMEM;
123	}
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);
131	if (ret) {
132		kfree(runtime);
133		kfree(data);
134	}
135	snd_card_unref(compr->card);
136	return ret;
137}
138
139static int snd_compr_free(struct inode *inode, struct file *f)
140{
141	struct snd_compr_file *data = f->private_data;
142	struct snd_compr_runtime *runtime = data->stream.runtime;
143
144	switch (runtime->state) {
145	case SNDRV_PCM_STATE_RUNNING:
146	case SNDRV_PCM_STATE_DRAINING:
147	case SNDRV_PCM_STATE_PAUSED:
148		data->stream.ops->trigger(&data->stream, SNDRV_PCM_TRIGGER_STOP);
149		break;
150	default:
151		break;
152	}
153
154	data->stream.ops->free(&data->stream);
155	kfree(data->stream.runtime->buffer);
156	kfree(data->stream.runtime);
157	kfree(data);
158	return 0;
159}
160
161static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
162		struct snd_compr_tstamp *tstamp)
163{
164	if (!stream->ops->pointer)
165		return -ENOTSUPP;
166	stream->ops->pointer(stream, tstamp);
167	pr_debug("dsp consumed till %d total %d bytes\n",
168		tstamp->byte_offset, tstamp->copied_total);
169	if (stream->direction == SND_COMPRESS_PLAYBACK)
170		stream->runtime->total_bytes_transferred = tstamp->copied_total;
171	else
172		stream->runtime->total_bytes_available = tstamp->copied_total;
173	return 0;
174}
175
176static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
177		struct snd_compr_avail *avail)
178{
179	memset(avail, 0, sizeof(*avail));
180	snd_compr_update_tstamp(stream, &avail->tstamp);
181	/* Still need to return avail even if tstamp can't be filled in */
182
183	if (stream->runtime->total_bytes_available == 0 &&
184			stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
185			stream->direction == SND_COMPRESS_PLAYBACK) {
186		pr_debug("detected init and someone forgot to do a write\n");
187		return stream->runtime->buffer_size;
188	}
189	pr_debug("app wrote %lld, DSP consumed %lld\n",
190			stream->runtime->total_bytes_available,
191			stream->runtime->total_bytes_transferred);
192	if (stream->runtime->total_bytes_available ==
193				stream->runtime->total_bytes_transferred) {
194		if (stream->direction == SND_COMPRESS_PLAYBACK) {
195			pr_debug("both pointers are same, returning full avail\n");
196			return stream->runtime->buffer_size;
197		} else {
198			pr_debug("both pointers are same, returning no avail\n");
199			return 0;
200		}
201	}
202
203	avail->avail = stream->runtime->total_bytes_available -
204			stream->runtime->total_bytes_transferred;
205	if (stream->direction == SND_COMPRESS_PLAYBACK)
206		avail->avail = stream->runtime->buffer_size - avail->avail;
207
208	pr_debug("ret avail as %lld\n", avail->avail);
209	return avail->avail;
210}
211
212static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
213{
214	struct snd_compr_avail avail;
215
216	return snd_compr_calc_avail(stream, &avail);
217}
218
219static int
220snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
221{
222	struct snd_compr_avail ioctl_avail;
223	size_t avail;
224
225	avail = snd_compr_calc_avail(stream, &ioctl_avail);
226	ioctl_avail.avail = avail;
227
228	if (copy_to_user((__u64 __user *)arg,
229				&ioctl_avail, sizeof(ioctl_avail)))
230		return -EFAULT;
231	return 0;
232}
233
234static int snd_compr_write_data(struct snd_compr_stream *stream,
235	       const char __user *buf, size_t count)
236{
237	void *dstn;
238	size_t copy;
239	struct snd_compr_runtime *runtime = stream->runtime;
240	/* 64-bit Modulus */
241	u64 app_pointer = div64_u64(runtime->total_bytes_available,
242				    runtime->buffer_size);
243	app_pointer = runtime->total_bytes_available -
244		      (app_pointer * runtime->buffer_size);
245
246	dstn = runtime->buffer + app_pointer;
247	pr_debug("copying %ld at %lld\n",
248			(unsigned long)count, app_pointer);
249	if (count < runtime->buffer_size - app_pointer) {
250		if (copy_from_user(dstn, buf, count))
251			return -EFAULT;
252	} else {
253		copy = runtime->buffer_size - app_pointer;
254		if (copy_from_user(dstn, buf, copy))
255			return -EFAULT;
256		if (copy_from_user(runtime->buffer, buf + copy, count - copy))
257			return -EFAULT;
258	}
259	/* if DSP cares, let it know data has been written */
260	if (stream->ops->ack)
261		stream->ops->ack(stream, count);
262	return count;
263}
264
265static ssize_t snd_compr_write(struct file *f, const char __user *buf,
266		size_t count, loff_t *offset)
267{
268	struct snd_compr_file *data = f->private_data;
269	struct snd_compr_stream *stream;
270	size_t avail;
271	int retval;
272
273	if (snd_BUG_ON(!data))
274		return -EFAULT;
275
276	stream = &data->stream;
277	mutex_lock(&stream->device->lock);
278	/* write is allowed when stream is running or has been steup */
279	if (stream->runtime->state != SNDRV_PCM_STATE_SETUP &&
 
280			stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
281		mutex_unlock(&stream->device->lock);
282		return -EBADFD;
283	}
284
285	avail = snd_compr_get_avail(stream);
286	pr_debug("avail returned %ld\n", (unsigned long)avail);
287	/* calculate how much we can write to buffer */
288	if (avail > count)
289		avail = count;
290
291	if (stream->ops->copy) {
292		char __user* cbuf = (char __user*)buf;
293		retval = stream->ops->copy(stream, cbuf, avail);
294	} else {
295		retval = snd_compr_write_data(stream, buf, avail);
296	}
297	if (retval > 0)
298		stream->runtime->total_bytes_available += retval;
299
300	/* while initiating the stream, write should be called before START
301	 * call, so in setup move state */
302	if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
303		stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
304		pr_debug("stream prepared, Houston we are good to go\n");
305	}
306
307	mutex_unlock(&stream->device->lock);
308	return retval;
309}
310
311
312static ssize_t snd_compr_read(struct file *f, char __user *buf,
313		size_t count, loff_t *offset)
314{
315	struct snd_compr_file *data = f->private_data;
316	struct snd_compr_stream *stream;
317	size_t avail;
318	int retval;
319
320	if (snd_BUG_ON(!data))
321		return -EFAULT;
322
323	stream = &data->stream;
324	mutex_lock(&stream->device->lock);
325
326	/* read is allowed when stream is running, paused, draining and setup
327	 * (yes setup is state which we transition to after stop, so if user
328	 * wants to read data after stop we allow that)
329	 */
330	switch (stream->runtime->state) {
331	case SNDRV_PCM_STATE_OPEN:
332	case SNDRV_PCM_STATE_PREPARED:
333	case SNDRV_PCM_STATE_XRUN:
334	case SNDRV_PCM_STATE_SUSPENDED:
335	case SNDRV_PCM_STATE_DISCONNECTED:
336		retval = -EBADFD;
337		goto out;
338	}
339
340	avail = snd_compr_get_avail(stream);
341	pr_debug("avail returned %ld\n", (unsigned long)avail);
342	/* calculate how much we can read from buffer */
343	if (avail > count)
344		avail = count;
345
346	if (stream->ops->copy) {
347		retval = stream->ops->copy(stream, buf, avail);
348	} else {
349		retval = -ENXIO;
350		goto out;
351	}
352	if (retval > 0)
353		stream->runtime->total_bytes_transferred += retval;
354
355out:
356	mutex_unlock(&stream->device->lock);
357	return retval;
358}
359
360static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
361{
362	return -ENXIO;
363}
364
365static inline int snd_compr_get_poll(struct snd_compr_stream *stream)
366{
367	if (stream->direction == SND_COMPRESS_PLAYBACK)
368		return POLLOUT | POLLWRNORM;
369	else
370		return POLLIN | POLLRDNORM;
371}
372
373static unsigned int snd_compr_poll(struct file *f, poll_table *wait)
374{
375	struct snd_compr_file *data = f->private_data;
376	struct snd_compr_stream *stream;
377	size_t avail;
378	int retval = 0;
379
380	if (snd_BUG_ON(!data))
381		return -EFAULT;
382	stream = &data->stream;
383	if (snd_BUG_ON(!stream))
384		return -EFAULT;
385
386	mutex_lock(&stream->device->lock);
387	if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
388		retval = -EBADFD;
389		goto out;
390	}
391	poll_wait(f, &stream->runtime->sleep, wait);
392
393	avail = snd_compr_get_avail(stream);
394	pr_debug("avail is %ld\n", (unsigned long)avail);
395	/* check if we have at least one fragment to fill */
396	switch (stream->runtime->state) {
397	case SNDRV_PCM_STATE_DRAINING:
398		/* stream has been woken up after drain is complete
399		 * draining done so set stream state to stopped
400		 */
401		retval = snd_compr_get_poll(stream);
402		stream->runtime->state = SNDRV_PCM_STATE_SETUP;
403		break;
404	case SNDRV_PCM_STATE_RUNNING:
405	case SNDRV_PCM_STATE_PREPARED:
406	case SNDRV_PCM_STATE_PAUSED:
407		if (avail >= stream->runtime->fragment_size)
408			retval = snd_compr_get_poll(stream);
409		break;
410	default:
411		if (stream->direction == SND_COMPRESS_PLAYBACK)
412			retval = POLLOUT | POLLWRNORM | POLLERR;
413		else
414			retval = POLLIN | POLLRDNORM | POLLERR;
415		break;
416	}
417out:
418	mutex_unlock(&stream->device->lock);
419	return retval;
420}
421
422static int
423snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
424{
425	int retval;
426	struct snd_compr_caps caps;
427
428	if (!stream->ops->get_caps)
429		return -ENXIO;
430
431	memset(&caps, 0, sizeof(caps));
432	retval = stream->ops->get_caps(stream, &caps);
433	if (retval)
434		goto out;
435	if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
436		retval = -EFAULT;
437out:
438	return retval;
439}
440
 
441static int
442snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
443{
444	int retval;
445	struct snd_compr_codec_caps *caps;
446
447	if (!stream->ops->get_codec_caps)
448		return -ENXIO;
449
450	caps = kzalloc(sizeof(*caps), GFP_KERNEL);
451	if (!caps)
452		return -ENOMEM;
453
454	retval = stream->ops->get_codec_caps(stream, caps);
455	if (retval)
456		goto out;
457	if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
458		retval = -EFAULT;
459
460out:
461	kfree(caps);
462	return retval;
463}
 
464
465/* revisit this with snd_pcm_preallocate_xxx */
466static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
467		struct snd_compr_params *params)
468{
469	unsigned int buffer_size;
470	void *buffer;
471
472	buffer_size = params->buffer.fragment_size * params->buffer.fragments;
473	if (stream->ops->copy) {
474		buffer = NULL;
475		/* if copy is defined the driver will be required to copy
476		 * the data from core
477		 */
478	} else {
479		buffer = kmalloc(buffer_size, GFP_KERNEL);
480		if (!buffer)
481			return -ENOMEM;
482	}
483	stream->runtime->fragment_size = params->buffer.fragment_size;
484	stream->runtime->fragments = params->buffer.fragments;
485	stream->runtime->buffer = buffer;
486	stream->runtime->buffer_size = buffer_size;
487	return 0;
488}
489
490static int snd_compress_check_input(struct snd_compr_params *params)
491{
492	/* first let's check the buffer parameter's */
493	if (params->buffer.fragment_size == 0 ||
494			params->buffer.fragments > SIZE_MAX / params->buffer.fragment_size)
495		return -EINVAL;
496
497	/* now codec parameters */
498	if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
499		return -EINVAL;
500
501	if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
502		return -EINVAL;
503
504	return 0;
505}
506
507static int
508snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
509{
510	struct snd_compr_params *params;
511	int retval;
512
513	if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
514		/*
515		 * we should allow parameter change only when stream has been
516		 * opened not in other cases
517		 */
518		params = kmalloc(sizeof(*params), GFP_KERNEL);
519		if (!params)
520			return -ENOMEM;
521		if (copy_from_user(params, (void __user *)arg, sizeof(*params))) {
522			retval = -EFAULT;
523			goto out;
524		}
525
526		retval = snd_compress_check_input(params);
527		if (retval)
528			goto out;
529
530		retval = snd_compr_allocate_buffer(stream, params);
531		if (retval) {
532			retval = -ENOMEM;
533			goto out;
534		}
535
536		retval = stream->ops->set_params(stream, params);
537		if (retval)
538			goto out;
539
540		stream->metadata_set = false;
541		stream->next_track = false;
542
543		if (stream->direction == SND_COMPRESS_PLAYBACK)
544			stream->runtime->state = SNDRV_PCM_STATE_SETUP;
545		else
546			stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
547	} else {
548		return -EPERM;
549	}
550out:
551	kfree(params);
552	return retval;
553}
554
555static int
556snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
557{
558	struct snd_codec *params;
559	int retval;
560
561	if (!stream->ops->get_params)
562		return -EBADFD;
563
564	params = kzalloc(sizeof(*params), GFP_KERNEL);
565	if (!params)
566		return -ENOMEM;
567	retval = stream->ops->get_params(stream, params);
568	if (retval)
569		goto out;
570	if (copy_to_user((char __user *)arg, params, sizeof(*params)))
571		retval = -EFAULT;
572
573out:
574	kfree(params);
575	return retval;
576}
577
578static int
579snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
580{
581	struct snd_compr_metadata metadata;
582	int retval;
583
584	if (!stream->ops->get_metadata)
585		return -ENXIO;
586
587	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
588		return -EFAULT;
589
590	retval = stream->ops->get_metadata(stream, &metadata);
591	if (retval != 0)
592		return retval;
593
594	if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
595		return -EFAULT;
596
597	return 0;
598}
599
600static int
601snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
602{
603	struct snd_compr_metadata metadata;
604	int retval;
605
606	if (!stream->ops->set_metadata)
607		return -ENXIO;
608	/*
609	* we should allow parameter change only when stream has been
610	* opened not in other cases
611	*/
612	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
613		return -EFAULT;
614
615	retval = stream->ops->set_metadata(stream, &metadata);
616	stream->metadata_set = true;
617
618	return retval;
619}
620
621static inline int
622snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
623{
624	struct snd_compr_tstamp tstamp = {0};
625	int ret;
626
627	ret = snd_compr_update_tstamp(stream, &tstamp);
628	if (ret == 0)
629		ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
630			&tstamp, sizeof(tstamp)) ? -EFAULT : 0;
631	return ret;
632}
633
634static int snd_compr_pause(struct snd_compr_stream *stream)
635{
636	int retval;
637
638	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
639		return -EPERM;
640	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
641	if (!retval)
642		stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
643	return retval;
644}
645
646static int snd_compr_resume(struct snd_compr_stream *stream)
647{
648	int retval;
649
650	if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
651		return -EPERM;
652	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
653	if (!retval)
654		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
655	return retval;
656}
657
658static int snd_compr_start(struct snd_compr_stream *stream)
659{
660	int retval;
661
662	if (stream->runtime->state != SNDRV_PCM_STATE_PREPARED)
663		return -EPERM;
664	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
665	if (!retval)
666		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
667	return retval;
668}
669
670static int snd_compr_stop(struct snd_compr_stream *stream)
671{
672	int retval;
673
674	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
675			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
676		return -EPERM;
677	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
678	if (!retval) {
679		snd_compr_drain_notify(stream);
680		stream->runtime->total_bytes_available = 0;
681		stream->runtime->total_bytes_transferred = 0;
682	}
683	return retval;
684}
685
686static int snd_compress_wait_for_drain(struct snd_compr_stream *stream)
687{
688	int ret;
689
690	/*
691	 * We are called with lock held. So drop the lock while we wait for
692	 * drain complete notfication from the driver
693	 *
694	 * It is expected that driver will notify the drain completion and then
695	 * stream will be moved to SETUP state, even if draining resulted in an
696	 * error. We can trigger next track after this.
697	 */
698	stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
699	mutex_unlock(&stream->device->lock);
700
701	/* we wait for drain to complete here, drain can return when
702	 * interruption occurred, wait returned error or success.
703	 * For the first two cases we don't do anything different here and
704	 * return after waking up
705	 */
706
707	ret = wait_event_interruptible(stream->runtime->sleep,
708			(stream->runtime->state != SNDRV_PCM_STATE_DRAINING));
709	if (ret == -ERESTARTSYS)
710		pr_debug("wait aborted by a signal");
711	else if (ret)
712		pr_debug("wait for drain failed with %d\n", ret);
713
714
715	wake_up(&stream->runtime->sleep);
716	mutex_lock(&stream->device->lock);
717
718	return ret;
719}
720
721static int snd_compr_drain(struct snd_compr_stream *stream)
722{
723	int retval;
724
725	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
726			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
727		return -EPERM;
728
729	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
730	if (retval) {
731		pr_debug("SND_COMPR_TRIGGER_DRAIN failed %d\n", retval);
732		wake_up(&stream->runtime->sleep);
733		return retval;
734	}
735
736	return snd_compress_wait_for_drain(stream);
737}
738
739static int snd_compr_next_track(struct snd_compr_stream *stream)
740{
741	int retval;
742
743	/* only a running stream can transition to next track */
744	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
745		return -EPERM;
746
747	/* you can signal next track isf this is intended to be a gapless stream
748	 * and current track metadata is set
749	 */
750	if (stream->metadata_set == false)
751		return -EPERM;
752
753	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
754	if (retval != 0)
755		return retval;
756	stream->metadata_set = false;
757	stream->next_track = true;
758	return 0;
759}
760
761static int snd_compr_partial_drain(struct snd_compr_stream *stream)
762{
763	int retval;
764	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
765			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
766		return -EPERM;
767	/* stream can be drained only when next track has been signalled */
768	if (stream->next_track == false)
769		return -EPERM;
770
771	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
772	if (retval) {
773		pr_debug("Partial drain returned failure\n");
774		wake_up(&stream->runtime->sleep);
775		return retval;
776	}
777
778	stream->next_track = false;
779	return snd_compress_wait_for_drain(stream);
780}
781
782static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
783{
784	struct snd_compr_file *data = f->private_data;
785	struct snd_compr_stream *stream;
786	int retval = -ENOTTY;
787
788	if (snd_BUG_ON(!data))
789		return -EFAULT;
790	stream = &data->stream;
791	if (snd_BUG_ON(!stream))
792		return -EFAULT;
793	mutex_lock(&stream->device->lock);
794	switch (_IOC_NR(cmd)) {
795	case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
796		retval = put_user(SNDRV_COMPRESS_VERSION,
797				(int __user *)arg) ? -EFAULT : 0;
798		break;
799	case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
800		retval = snd_compr_get_caps(stream, arg);
801		break;
 
802	case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
803		retval = snd_compr_get_codec_caps(stream, arg);
804		break;
 
805	case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
806		retval = snd_compr_set_params(stream, arg);
807		break;
808	case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
809		retval = snd_compr_get_params(stream, arg);
810		break;
811	case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
812		retval = snd_compr_set_metadata(stream, arg);
813		break;
814	case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
815		retval = snd_compr_get_metadata(stream, arg);
816		break;
817	case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
818		retval = snd_compr_tstamp(stream, arg);
819		break;
820	case _IOC_NR(SNDRV_COMPRESS_AVAIL):
821		retval = snd_compr_ioctl_avail(stream, arg);
822		break;
823	case _IOC_NR(SNDRV_COMPRESS_PAUSE):
824		retval = snd_compr_pause(stream);
825		break;
826	case _IOC_NR(SNDRV_COMPRESS_RESUME):
827		retval = snd_compr_resume(stream);
828		break;
829	case _IOC_NR(SNDRV_COMPRESS_START):
830		retval = snd_compr_start(stream);
831		break;
832	case _IOC_NR(SNDRV_COMPRESS_STOP):
833		retval = snd_compr_stop(stream);
834		break;
835	case _IOC_NR(SNDRV_COMPRESS_DRAIN):
836		retval = snd_compr_drain(stream);
837		break;
838	case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
839		retval = snd_compr_partial_drain(stream);
840		break;
841	case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
842		retval = snd_compr_next_track(stream);
843		break;
844
845	}
846	mutex_unlock(&stream->device->lock);
847	return retval;
848}
849
 
 
 
 
 
 
 
 
 
850static const struct file_operations snd_compr_file_ops = {
851		.owner =	THIS_MODULE,
852		.open =		snd_compr_open,
853		.release =	snd_compr_free,
854		.write =	snd_compr_write,
855		.read =		snd_compr_read,
856		.unlocked_ioctl = snd_compr_ioctl,
 
 
 
857		.mmap =		snd_compr_mmap,
858		.poll =		snd_compr_poll,
859};
860
861static int snd_compress_dev_register(struct snd_device *device)
862{
863	int ret = -EINVAL;
864	char str[16];
865	struct snd_compr *compr;
866
867	if (snd_BUG_ON(!device || !device->device_data))
868		return -EBADFD;
869	compr = device->device_data;
870
871	sprintf(str, "comprC%iD%i", compr->card->number, compr->device);
872	pr_debug("reg %s for device %s, direction %d\n", str, compr->name,
873			compr->direction);
874	/* register compressed device */
875	ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS, compr->card,
876			compr->device, &snd_compr_file_ops, compr, str);
 
877	if (ret < 0) {
878		pr_err("snd_register_device failed\n %d", ret);
879		return ret;
880	}
881	return ret;
882
883}
884
885static int snd_compress_dev_disconnect(struct snd_device *device)
886{
887	struct snd_compr *compr;
888
889	compr = device->device_data;
890	snd_unregister_device(SNDRV_DEVICE_TYPE_COMPRESS, compr->card,
891		compr->device);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
892	return 0;
893}
894
895/*
896 * snd_compress_new: create new compress device
897 * @card: sound card pointer
898 * @device: device number
899 * @dirn: device direction, should be of type enum snd_compr_direction
900 * @compr: compress device pointer
901 */
902int snd_compress_new(struct snd_card *card, int device,
903			int dirn, struct snd_compr *compr)
904{
905	static struct snd_device_ops ops = {
906		.dev_free = NULL,
907		.dev_register = snd_compress_dev_register,
908		.dev_disconnect = snd_compress_dev_disconnect,
909	};
 
910
911	compr->card = card;
912	compr->device = device;
913	compr->direction = dirn;
914	return snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
 
 
 
 
 
 
 
 
 
 
915}
916EXPORT_SYMBOL_GPL(snd_compress_new);
917
918static int snd_compress_add_device(struct snd_compr *device)
919{
920	int ret;
921
922	if (!device->card)
923		return -EINVAL;
924
925	/* register the card */
926	ret = snd_card_register(device->card);
927	if (ret)
928		goto out;
929	return 0;
930
931out:
932	pr_err("failed with %d\n", ret);
933	return ret;
934
935}
936
937static int snd_compress_remove_device(struct snd_compr *device)
938{
939	return snd_card_free(device->card);
940}
941
942/**
943 * snd_compress_register - register compressed device
944 *
945 * @device: compressed device to register
946 */
947int snd_compress_register(struct snd_compr *device)
948{
949	int retval;
950
951	if (device->name == NULL || device->dev == NULL || device->ops == NULL)
952		return -EINVAL;
953
954	pr_debug("Registering compressed device %s\n", device->name);
955	if (snd_BUG_ON(!device->ops->open))
956		return -EINVAL;
957	if (snd_BUG_ON(!device->ops->free))
958		return -EINVAL;
959	if (snd_BUG_ON(!device->ops->set_params))
960		return -EINVAL;
961	if (snd_BUG_ON(!device->ops->trigger))
962		return -EINVAL;
963
964	mutex_init(&device->lock);
965
966	/* register a compressed card */
967	mutex_lock(&device_mutex);
968	retval = snd_compress_add_device(device);
969	mutex_unlock(&device_mutex);
970	return retval;
971}
972EXPORT_SYMBOL_GPL(snd_compress_register);
973
974int snd_compress_deregister(struct snd_compr *device)
975{
976	pr_debug("Removing compressed device %s\n", device->name);
977	mutex_lock(&device_mutex);
978	snd_compress_remove_device(device);
979	mutex_unlock(&device_mutex);
980	return 0;
981}
982EXPORT_SYMBOL_GPL(snd_compress_deregister);
983
984static int __init snd_compress_init(void)
985{
986	return 0;
987}
988
989static void __exit snd_compress_exit(void)
990{
991}
992
993module_init(snd_compress_init);
994module_exit(snd_compress_exit);
995
996MODULE_DESCRIPTION("ALSA Compressed offload framework");
997MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
998MODULE_LICENSE("GPL v2");
v4.6
   1/*
   2 *  compress_core.c - compress offload core
   3 *
   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 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   8 *
   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.
  12 *
  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.
  17 *
  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.
  21 *
  22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  23 *
  24 */
  25#define FORMAT(fmt) "%s: %d: " fmt, __func__, __LINE__
  26#define pr_fmt(fmt) KBUILD_MODNAME ": " FORMAT(fmt)
  27
  28#include <linux/file.h>
  29#include <linux/fs.h>
  30#include <linux/list.h>
  31#include <linux/math64.h>
  32#include <linux/mm.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 <linux/compat.h>
  42#include <sound/core.h>
  43#include <sound/initval.h>
  44#include <sound/info.h>
  45#include <sound/compress_params.h>
  46#include <sound/compress_offload.h>
  47#include <sound/compress_driver.h>
  48
  49/* struct snd_compr_codec_caps overflows the ioctl bit size for some
  50 * architectures, so we need to disable the relevant ioctls.
  51 */
  52#if _IOC_SIZEBITS < 14
  53#define COMPR_CODEC_CAPS_OVERFLOW
  54#endif
  55
  56/* TODO:
  57 * - add substream support for multiple devices in case of
  58 *	SND_DYNAMIC_MINORS is not used
  59 * - Multiple node representation
  60 *	driver should be able to register multiple nodes
  61 */
  62
  63static DEFINE_MUTEX(device_mutex);
  64
  65struct snd_compr_file {
  66	unsigned long caps;
  67	struct snd_compr_stream stream;
  68};
  69
  70/*
  71 * a note on stream states used:
  72 * we use following states in the compressed core
  73 * SNDRV_PCM_STATE_OPEN: When stream has been opened.
  74 * SNDRV_PCM_STATE_SETUP: When stream has been initialized. This is done by
  75 *	calling SNDRV_COMPRESS_SET_PARAMS. Running streams will come to this
  76 *	state at stop by calling SNDRV_COMPRESS_STOP, or at end of drain.
  77 * SNDRV_PCM_STATE_PREPARED: When a stream has been written to (for
  78 *	playback only). User after setting up stream writes the data buffer
  79 *	before starting the stream.
  80 * SNDRV_PCM_STATE_RUNNING: When stream has been started and is
  81 *	decoding/encoding and rendering/capturing data.
  82 * SNDRV_PCM_STATE_DRAINING: When stream is draining current data. This is done
  83 *	by calling SNDRV_COMPRESS_DRAIN.
  84 * SNDRV_PCM_STATE_PAUSED: When stream is paused. This is done by calling
  85 *	SNDRV_COMPRESS_PAUSE. It can be stopped or resumed by calling
  86 *	SNDRV_COMPRESS_STOP or SNDRV_COMPRESS_RESUME respectively.
  87 */
  88static int snd_compr_open(struct inode *inode, struct file *f)
  89{
  90	struct snd_compr *compr;
  91	struct snd_compr_file *data;
  92	struct snd_compr_runtime *runtime;
  93	enum snd_compr_direction dirn;
  94	int maj = imajor(inode);
  95	int ret;
  96
  97	if ((f->f_flags & O_ACCMODE) == O_WRONLY)
  98		dirn = SND_COMPRESS_PLAYBACK;
  99	else if ((f->f_flags & O_ACCMODE) == O_RDONLY)
 100		dirn = SND_COMPRESS_CAPTURE;
 101	else
 102		return -EINVAL;
 103
 104	if (maj == snd_major)
 105		compr = snd_lookup_minor_data(iminor(inode),
 106					SNDRV_DEVICE_TYPE_COMPRESS);
 107	else
 108		return -EBADFD;
 109
 110	if (compr == NULL) {
 111		pr_err("no device data!!!\n");
 112		return -ENODEV;
 113	}
 114
 115	if (dirn != compr->direction) {
 116		pr_err("this device doesn't support this direction\n");
 117		snd_card_unref(compr->card);
 118		return -EINVAL;
 119	}
 120
 121	data = kzalloc(sizeof(*data), GFP_KERNEL);
 122	if (!data) {
 123		snd_card_unref(compr->card);
 124		return -ENOMEM;
 125	}
 126	data->stream.ops = compr->ops;
 127	data->stream.direction = dirn;
 128	data->stream.private_data = compr->private_data;
 129	data->stream.device = compr;
 130	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
 131	if (!runtime) {
 132		kfree(data);
 133		snd_card_unref(compr->card);
 134		return -ENOMEM;
 135	}
 136	runtime->state = SNDRV_PCM_STATE_OPEN;
 137	init_waitqueue_head(&runtime->sleep);
 138	data->stream.runtime = runtime;
 139	f->private_data = (void *)data;
 140	mutex_lock(&compr->lock);
 141	ret = compr->ops->open(&data->stream);
 142	mutex_unlock(&compr->lock);
 143	if (ret) {
 144		kfree(runtime);
 145		kfree(data);
 146	}
 147	snd_card_unref(compr->card);
 148	return ret;
 149}
 150
 151static int snd_compr_free(struct inode *inode, struct file *f)
 152{
 153	struct snd_compr_file *data = f->private_data;
 154	struct snd_compr_runtime *runtime = data->stream.runtime;
 155
 156	switch (runtime->state) {
 157	case SNDRV_PCM_STATE_RUNNING:
 158	case SNDRV_PCM_STATE_DRAINING:
 159	case SNDRV_PCM_STATE_PAUSED:
 160		data->stream.ops->trigger(&data->stream, SNDRV_PCM_TRIGGER_STOP);
 161		break;
 162	default:
 163		break;
 164	}
 165
 166	data->stream.ops->free(&data->stream);
 167	kfree(data->stream.runtime->buffer);
 168	kfree(data->stream.runtime);
 169	kfree(data);
 170	return 0;
 171}
 172
 173static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
 174		struct snd_compr_tstamp *tstamp)
 175{
 176	if (!stream->ops->pointer)
 177		return -ENOTSUPP;
 178	stream->ops->pointer(stream, tstamp);
 179	pr_debug("dsp consumed till %d total %d bytes\n",
 180		tstamp->byte_offset, tstamp->copied_total);
 181	if (stream->direction == SND_COMPRESS_PLAYBACK)
 182		stream->runtime->total_bytes_transferred = tstamp->copied_total;
 183	else
 184		stream->runtime->total_bytes_available = tstamp->copied_total;
 185	return 0;
 186}
 187
 188static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
 189		struct snd_compr_avail *avail)
 190{
 191	memset(avail, 0, sizeof(*avail));
 192	snd_compr_update_tstamp(stream, &avail->tstamp);
 193	/* Still need to return avail even if tstamp can't be filled in */
 194
 195	if (stream->runtime->total_bytes_available == 0 &&
 196			stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
 197			stream->direction == SND_COMPRESS_PLAYBACK) {
 198		pr_debug("detected init and someone forgot to do a write\n");
 199		return stream->runtime->buffer_size;
 200	}
 201	pr_debug("app wrote %lld, DSP consumed %lld\n",
 202			stream->runtime->total_bytes_available,
 203			stream->runtime->total_bytes_transferred);
 204	if (stream->runtime->total_bytes_available ==
 205				stream->runtime->total_bytes_transferred) {
 206		if (stream->direction == SND_COMPRESS_PLAYBACK) {
 207			pr_debug("both pointers are same, returning full avail\n");
 208			return stream->runtime->buffer_size;
 209		} else {
 210			pr_debug("both pointers are same, returning no avail\n");
 211			return 0;
 212		}
 213	}
 214
 215	avail->avail = stream->runtime->total_bytes_available -
 216			stream->runtime->total_bytes_transferred;
 217	if (stream->direction == SND_COMPRESS_PLAYBACK)
 218		avail->avail = stream->runtime->buffer_size - avail->avail;
 219
 220	pr_debug("ret avail as %lld\n", avail->avail);
 221	return avail->avail;
 222}
 223
 224static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
 225{
 226	struct snd_compr_avail avail;
 227
 228	return snd_compr_calc_avail(stream, &avail);
 229}
 230
 231static int
 232snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
 233{
 234	struct snd_compr_avail ioctl_avail;
 235	size_t avail;
 236
 237	avail = snd_compr_calc_avail(stream, &ioctl_avail);
 238	ioctl_avail.avail = avail;
 239
 240	if (copy_to_user((__u64 __user *)arg,
 241				&ioctl_avail, sizeof(ioctl_avail)))
 242		return -EFAULT;
 243	return 0;
 244}
 245
 246static int snd_compr_write_data(struct snd_compr_stream *stream,
 247	       const char __user *buf, size_t count)
 248{
 249	void *dstn;
 250	size_t copy;
 251	struct snd_compr_runtime *runtime = stream->runtime;
 252	/* 64-bit Modulus */
 253	u64 app_pointer = div64_u64(runtime->total_bytes_available,
 254				    runtime->buffer_size);
 255	app_pointer = runtime->total_bytes_available -
 256		      (app_pointer * runtime->buffer_size);
 257
 258	dstn = runtime->buffer + app_pointer;
 259	pr_debug("copying %ld at %lld\n",
 260			(unsigned long)count, app_pointer);
 261	if (count < runtime->buffer_size - app_pointer) {
 262		if (copy_from_user(dstn, buf, count))
 263			return -EFAULT;
 264	} else {
 265		copy = runtime->buffer_size - app_pointer;
 266		if (copy_from_user(dstn, buf, copy))
 267			return -EFAULT;
 268		if (copy_from_user(runtime->buffer, buf + copy, count - copy))
 269			return -EFAULT;
 270	}
 271	/* if DSP cares, let it know data has been written */
 272	if (stream->ops->ack)
 273		stream->ops->ack(stream, count);
 274	return count;
 275}
 276
 277static ssize_t snd_compr_write(struct file *f, const char __user *buf,
 278		size_t count, loff_t *offset)
 279{
 280	struct snd_compr_file *data = f->private_data;
 281	struct snd_compr_stream *stream;
 282	size_t avail;
 283	int retval;
 284
 285	if (snd_BUG_ON(!data))
 286		return -EFAULT;
 287
 288	stream = &data->stream;
 289	mutex_lock(&stream->device->lock);
 290	/* write is allowed when stream is running or has been steup */
 291	if (stream->runtime->state != SNDRV_PCM_STATE_SETUP &&
 292	    stream->runtime->state != SNDRV_PCM_STATE_PREPARED &&
 293			stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
 294		mutex_unlock(&stream->device->lock);
 295		return -EBADFD;
 296	}
 297
 298	avail = snd_compr_get_avail(stream);
 299	pr_debug("avail returned %ld\n", (unsigned long)avail);
 300	/* calculate how much we can write to buffer */
 301	if (avail > count)
 302		avail = count;
 303
 304	if (stream->ops->copy) {
 305		char __user* cbuf = (char __user*)buf;
 306		retval = stream->ops->copy(stream, cbuf, avail);
 307	} else {
 308		retval = snd_compr_write_data(stream, buf, avail);
 309	}
 310	if (retval > 0)
 311		stream->runtime->total_bytes_available += retval;
 312
 313	/* while initiating the stream, write should be called before START
 314	 * call, so in setup move state */
 315	if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
 316		stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
 317		pr_debug("stream prepared, Houston we are good to go\n");
 318	}
 319
 320	mutex_unlock(&stream->device->lock);
 321	return retval;
 322}
 323
 324
 325static ssize_t snd_compr_read(struct file *f, char __user *buf,
 326		size_t count, loff_t *offset)
 327{
 328	struct snd_compr_file *data = f->private_data;
 329	struct snd_compr_stream *stream;
 330	size_t avail;
 331	int retval;
 332
 333	if (snd_BUG_ON(!data))
 334		return -EFAULT;
 335
 336	stream = &data->stream;
 337	mutex_lock(&stream->device->lock);
 338
 339	/* read is allowed when stream is running, paused, draining and setup
 340	 * (yes setup is state which we transition to after stop, so if user
 341	 * wants to read data after stop we allow that)
 342	 */
 343	switch (stream->runtime->state) {
 344	case SNDRV_PCM_STATE_OPEN:
 345	case SNDRV_PCM_STATE_PREPARED:
 346	case SNDRV_PCM_STATE_XRUN:
 347	case SNDRV_PCM_STATE_SUSPENDED:
 348	case SNDRV_PCM_STATE_DISCONNECTED:
 349		retval = -EBADFD;
 350		goto out;
 351	}
 352
 353	avail = snd_compr_get_avail(stream);
 354	pr_debug("avail returned %ld\n", (unsigned long)avail);
 355	/* calculate how much we can read from buffer */
 356	if (avail > count)
 357		avail = count;
 358
 359	if (stream->ops->copy) {
 360		retval = stream->ops->copy(stream, buf, avail);
 361	} else {
 362		retval = -ENXIO;
 363		goto out;
 364	}
 365	if (retval > 0)
 366		stream->runtime->total_bytes_transferred += retval;
 367
 368out:
 369	mutex_unlock(&stream->device->lock);
 370	return retval;
 371}
 372
 373static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
 374{
 375	return -ENXIO;
 376}
 377
 378static inline int snd_compr_get_poll(struct snd_compr_stream *stream)
 379{
 380	if (stream->direction == SND_COMPRESS_PLAYBACK)
 381		return POLLOUT | POLLWRNORM;
 382	else
 383		return POLLIN | POLLRDNORM;
 384}
 385
 386static unsigned int snd_compr_poll(struct file *f, poll_table *wait)
 387{
 388	struct snd_compr_file *data = f->private_data;
 389	struct snd_compr_stream *stream;
 390	size_t avail;
 391	int retval = 0;
 392
 393	if (snd_BUG_ON(!data))
 394		return -EFAULT;
 395	stream = &data->stream;
 396	if (snd_BUG_ON(!stream))
 397		return -EFAULT;
 398
 399	mutex_lock(&stream->device->lock);
 400	if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
 401		retval = -EBADFD;
 402		goto out;
 403	}
 404	poll_wait(f, &stream->runtime->sleep, wait);
 405
 406	avail = snd_compr_get_avail(stream);
 407	pr_debug("avail is %ld\n", (unsigned long)avail);
 408	/* check if we have at least one fragment to fill */
 409	switch (stream->runtime->state) {
 410	case SNDRV_PCM_STATE_DRAINING:
 411		/* stream has been woken up after drain is complete
 412		 * draining done so set stream state to stopped
 413		 */
 414		retval = snd_compr_get_poll(stream);
 415		stream->runtime->state = SNDRV_PCM_STATE_SETUP;
 416		break;
 417	case SNDRV_PCM_STATE_RUNNING:
 418	case SNDRV_PCM_STATE_PREPARED:
 419	case SNDRV_PCM_STATE_PAUSED:
 420		if (avail >= stream->runtime->fragment_size)
 421			retval = snd_compr_get_poll(stream);
 422		break;
 423	default:
 424		if (stream->direction == SND_COMPRESS_PLAYBACK)
 425			retval = POLLOUT | POLLWRNORM | POLLERR;
 426		else
 427			retval = POLLIN | POLLRDNORM | POLLERR;
 428		break;
 429	}
 430out:
 431	mutex_unlock(&stream->device->lock);
 432	return retval;
 433}
 434
 435static int
 436snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
 437{
 438	int retval;
 439	struct snd_compr_caps caps;
 440
 441	if (!stream->ops->get_caps)
 442		return -ENXIO;
 443
 444	memset(&caps, 0, sizeof(caps));
 445	retval = stream->ops->get_caps(stream, &caps);
 446	if (retval)
 447		goto out;
 448	if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
 449		retval = -EFAULT;
 450out:
 451	return retval;
 452}
 453
 454#ifndef COMPR_CODEC_CAPS_OVERFLOW
 455static int
 456snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
 457{
 458	int retval;
 459	struct snd_compr_codec_caps *caps;
 460
 461	if (!stream->ops->get_codec_caps)
 462		return -ENXIO;
 463
 464	caps = kzalloc(sizeof(*caps), GFP_KERNEL);
 465	if (!caps)
 466		return -ENOMEM;
 467
 468	retval = stream->ops->get_codec_caps(stream, caps);
 469	if (retval)
 470		goto out;
 471	if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
 472		retval = -EFAULT;
 473
 474out:
 475	kfree(caps);
 476	return retval;
 477}
 478#endif /* !COMPR_CODEC_CAPS_OVERFLOW */
 479
 480/* revisit this with snd_pcm_preallocate_xxx */
 481static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
 482		struct snd_compr_params *params)
 483{
 484	unsigned int buffer_size;
 485	void *buffer;
 486
 487	buffer_size = params->buffer.fragment_size * params->buffer.fragments;
 488	if (stream->ops->copy) {
 489		buffer = NULL;
 490		/* if copy is defined the driver will be required to copy
 491		 * the data from core
 492		 */
 493	} else {
 494		buffer = kmalloc(buffer_size, GFP_KERNEL);
 495		if (!buffer)
 496			return -ENOMEM;
 497	}
 498	stream->runtime->fragment_size = params->buffer.fragment_size;
 499	stream->runtime->fragments = params->buffer.fragments;
 500	stream->runtime->buffer = buffer;
 501	stream->runtime->buffer_size = buffer_size;
 502	return 0;
 503}
 504
 505static int snd_compress_check_input(struct snd_compr_params *params)
 506{
 507	/* first let's check the buffer parameter's */
 508	if (params->buffer.fragment_size == 0 ||
 509	    params->buffer.fragments > INT_MAX / params->buffer.fragment_size)
 510		return -EINVAL;
 511
 512	/* now codec parameters */
 513	if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
 514		return -EINVAL;
 515
 516	if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
 517		return -EINVAL;
 518
 519	return 0;
 520}
 521
 522static int
 523snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
 524{
 525	struct snd_compr_params *params;
 526	int retval;
 527
 528	if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
 529		/*
 530		 * we should allow parameter change only when stream has been
 531		 * opened not in other cases
 532		 */
 533		params = kmalloc(sizeof(*params), GFP_KERNEL);
 534		if (!params)
 535			return -ENOMEM;
 536		if (copy_from_user(params, (void __user *)arg, sizeof(*params))) {
 537			retval = -EFAULT;
 538			goto out;
 539		}
 540
 541		retval = snd_compress_check_input(params);
 542		if (retval)
 543			goto out;
 544
 545		retval = snd_compr_allocate_buffer(stream, params);
 546		if (retval) {
 547			retval = -ENOMEM;
 548			goto out;
 549		}
 550
 551		retval = stream->ops->set_params(stream, params);
 552		if (retval)
 553			goto out;
 554
 555		stream->metadata_set = false;
 556		stream->next_track = false;
 557
 558		if (stream->direction == SND_COMPRESS_PLAYBACK)
 559			stream->runtime->state = SNDRV_PCM_STATE_SETUP;
 560		else
 561			stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
 562	} else {
 563		return -EPERM;
 564	}
 565out:
 566	kfree(params);
 567	return retval;
 568}
 569
 570static int
 571snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
 572{
 573	struct snd_codec *params;
 574	int retval;
 575
 576	if (!stream->ops->get_params)
 577		return -EBADFD;
 578
 579	params = kzalloc(sizeof(*params), GFP_KERNEL);
 580	if (!params)
 581		return -ENOMEM;
 582	retval = stream->ops->get_params(stream, params);
 583	if (retval)
 584		goto out;
 585	if (copy_to_user((char __user *)arg, params, sizeof(*params)))
 586		retval = -EFAULT;
 587
 588out:
 589	kfree(params);
 590	return retval;
 591}
 592
 593static int
 594snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
 595{
 596	struct snd_compr_metadata metadata;
 597	int retval;
 598
 599	if (!stream->ops->get_metadata)
 600		return -ENXIO;
 601
 602	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
 603		return -EFAULT;
 604
 605	retval = stream->ops->get_metadata(stream, &metadata);
 606	if (retval != 0)
 607		return retval;
 608
 609	if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
 610		return -EFAULT;
 611
 612	return 0;
 613}
 614
 615static int
 616snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
 617{
 618	struct snd_compr_metadata metadata;
 619	int retval;
 620
 621	if (!stream->ops->set_metadata)
 622		return -ENXIO;
 623	/*
 624	* we should allow parameter change only when stream has been
 625	* opened not in other cases
 626	*/
 627	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
 628		return -EFAULT;
 629
 630	retval = stream->ops->set_metadata(stream, &metadata);
 631	stream->metadata_set = true;
 632
 633	return retval;
 634}
 635
 636static inline int
 637snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
 638{
 639	struct snd_compr_tstamp tstamp = {0};
 640	int ret;
 641
 642	ret = snd_compr_update_tstamp(stream, &tstamp);
 643	if (ret == 0)
 644		ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
 645			&tstamp, sizeof(tstamp)) ? -EFAULT : 0;
 646	return ret;
 647}
 648
 649static int snd_compr_pause(struct snd_compr_stream *stream)
 650{
 651	int retval;
 652
 653	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
 654		return -EPERM;
 655	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
 656	if (!retval)
 657		stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
 658	return retval;
 659}
 660
 661static int snd_compr_resume(struct snd_compr_stream *stream)
 662{
 663	int retval;
 664
 665	if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
 666		return -EPERM;
 667	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
 668	if (!retval)
 669		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
 670	return retval;
 671}
 672
 673static int snd_compr_start(struct snd_compr_stream *stream)
 674{
 675	int retval;
 676
 677	if (stream->runtime->state != SNDRV_PCM_STATE_PREPARED)
 678		return -EPERM;
 679	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
 680	if (!retval)
 681		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
 682	return retval;
 683}
 684
 685static int snd_compr_stop(struct snd_compr_stream *stream)
 686{
 687	int retval;
 688
 689	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 690			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 691		return -EPERM;
 692	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
 693	if (!retval) {
 694		snd_compr_drain_notify(stream);
 695		stream->runtime->total_bytes_available = 0;
 696		stream->runtime->total_bytes_transferred = 0;
 697	}
 698	return retval;
 699}
 700
 701static int snd_compress_wait_for_drain(struct snd_compr_stream *stream)
 702{
 703	int ret;
 704
 705	/*
 706	 * We are called with lock held. So drop the lock while we wait for
 707	 * drain complete notification from the driver
 708	 *
 709	 * It is expected that driver will notify the drain completion and then
 710	 * stream will be moved to SETUP state, even if draining resulted in an
 711	 * error. We can trigger next track after this.
 712	 */
 713	stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
 714	mutex_unlock(&stream->device->lock);
 715
 716	/* we wait for drain to complete here, drain can return when
 717	 * interruption occurred, wait returned error or success.
 718	 * For the first two cases we don't do anything different here and
 719	 * return after waking up
 720	 */
 721
 722	ret = wait_event_interruptible(stream->runtime->sleep,
 723			(stream->runtime->state != SNDRV_PCM_STATE_DRAINING));
 724	if (ret == -ERESTARTSYS)
 725		pr_debug("wait aborted by a signal");
 726	else if (ret)
 727		pr_debug("wait for drain failed with %d\n", ret);
 728
 729
 730	wake_up(&stream->runtime->sleep);
 731	mutex_lock(&stream->device->lock);
 732
 733	return ret;
 734}
 735
 736static int snd_compr_drain(struct snd_compr_stream *stream)
 737{
 738	int retval;
 739
 740	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 741			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 742		return -EPERM;
 743
 744	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
 745	if (retval) {
 746		pr_debug("SND_COMPR_TRIGGER_DRAIN failed %d\n", retval);
 747		wake_up(&stream->runtime->sleep);
 748		return retval;
 749	}
 750
 751	return snd_compress_wait_for_drain(stream);
 752}
 753
 754static int snd_compr_next_track(struct snd_compr_stream *stream)
 755{
 756	int retval;
 757
 758	/* only a running stream can transition to next track */
 759	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
 760		return -EPERM;
 761
 762	/* you can signal next track if this is intended to be a gapless stream
 763	 * and current track metadata is set
 764	 */
 765	if (stream->metadata_set == false)
 766		return -EPERM;
 767
 768	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
 769	if (retval != 0)
 770		return retval;
 771	stream->metadata_set = false;
 772	stream->next_track = true;
 773	return 0;
 774}
 775
 776static int snd_compr_partial_drain(struct snd_compr_stream *stream)
 777{
 778	int retval;
 779	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
 780			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
 781		return -EPERM;
 782	/* stream can be drained only when next track has been signalled */
 783	if (stream->next_track == false)
 784		return -EPERM;
 785
 786	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
 787	if (retval) {
 788		pr_debug("Partial drain returned failure\n");
 789		wake_up(&stream->runtime->sleep);
 790		return retval;
 791	}
 792
 793	stream->next_track = false;
 794	return snd_compress_wait_for_drain(stream);
 795}
 796
 797static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
 798{
 799	struct snd_compr_file *data = f->private_data;
 800	struct snd_compr_stream *stream;
 801	int retval = -ENOTTY;
 802
 803	if (snd_BUG_ON(!data))
 804		return -EFAULT;
 805	stream = &data->stream;
 806	if (snd_BUG_ON(!stream))
 807		return -EFAULT;
 808	mutex_lock(&stream->device->lock);
 809	switch (_IOC_NR(cmd)) {
 810	case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
 811		retval = put_user(SNDRV_COMPRESS_VERSION,
 812				(int __user *)arg) ? -EFAULT : 0;
 813		break;
 814	case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
 815		retval = snd_compr_get_caps(stream, arg);
 816		break;
 817#ifndef COMPR_CODEC_CAPS_OVERFLOW
 818	case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
 819		retval = snd_compr_get_codec_caps(stream, arg);
 820		break;
 821#endif
 822	case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
 823		retval = snd_compr_set_params(stream, arg);
 824		break;
 825	case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
 826		retval = snd_compr_get_params(stream, arg);
 827		break;
 828	case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
 829		retval = snd_compr_set_metadata(stream, arg);
 830		break;
 831	case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
 832		retval = snd_compr_get_metadata(stream, arg);
 833		break;
 834	case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
 835		retval = snd_compr_tstamp(stream, arg);
 836		break;
 837	case _IOC_NR(SNDRV_COMPRESS_AVAIL):
 838		retval = snd_compr_ioctl_avail(stream, arg);
 839		break;
 840	case _IOC_NR(SNDRV_COMPRESS_PAUSE):
 841		retval = snd_compr_pause(stream);
 842		break;
 843	case _IOC_NR(SNDRV_COMPRESS_RESUME):
 844		retval = snd_compr_resume(stream);
 845		break;
 846	case _IOC_NR(SNDRV_COMPRESS_START):
 847		retval = snd_compr_start(stream);
 848		break;
 849	case _IOC_NR(SNDRV_COMPRESS_STOP):
 850		retval = snd_compr_stop(stream);
 851		break;
 852	case _IOC_NR(SNDRV_COMPRESS_DRAIN):
 853		retval = snd_compr_drain(stream);
 854		break;
 855	case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
 856		retval = snd_compr_partial_drain(stream);
 857		break;
 858	case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
 859		retval = snd_compr_next_track(stream);
 860		break;
 861
 862	}
 863	mutex_unlock(&stream->device->lock);
 864	return retval;
 865}
 866
 867/* support of 32bit userspace on 64bit platforms */
 868#ifdef CONFIG_COMPAT
 869static long snd_compr_ioctl_compat(struct file *file, unsigned int cmd,
 870						unsigned long arg)
 871{
 872	return snd_compr_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
 873}
 874#endif
 875
 876static const struct file_operations snd_compr_file_ops = {
 877		.owner =	THIS_MODULE,
 878		.open =		snd_compr_open,
 879		.release =	snd_compr_free,
 880		.write =	snd_compr_write,
 881		.read =		snd_compr_read,
 882		.unlocked_ioctl = snd_compr_ioctl,
 883#ifdef CONFIG_COMPAT
 884		.compat_ioctl = snd_compr_ioctl_compat,
 885#endif
 886		.mmap =		snd_compr_mmap,
 887		.poll =		snd_compr_poll,
 888};
 889
 890static int snd_compress_dev_register(struct snd_device *device)
 891{
 892	int ret = -EINVAL;
 893	char str[16];
 894	struct snd_compr *compr;
 895
 896	if (snd_BUG_ON(!device || !device->device_data))
 897		return -EBADFD;
 898	compr = device->device_data;
 899
 
 900	pr_debug("reg %s for device %s, direction %d\n", str, compr->name,
 901			compr->direction);
 902	/* register compressed device */
 903	ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS,
 904				  compr->card, compr->device,
 905				  &snd_compr_file_ops, compr, &compr->dev);
 906	if (ret < 0) {
 907		pr_err("snd_register_device failed\n %d", ret);
 908		return ret;
 909	}
 910	return ret;
 911
 912}
 913
 914static int snd_compress_dev_disconnect(struct snd_device *device)
 915{
 916	struct snd_compr *compr;
 917
 918	compr = device->device_data;
 919	snd_unregister_device(&compr->dev);
 920	return 0;
 921}
 922
 923#ifdef CONFIG_SND_VERBOSE_PROCFS
 924static void snd_compress_proc_info_read(struct snd_info_entry *entry,
 925					struct snd_info_buffer *buffer)
 926{
 927	struct snd_compr *compr = (struct snd_compr *)entry->private_data;
 928
 929	snd_iprintf(buffer, "card: %d\n", compr->card->number);
 930	snd_iprintf(buffer, "device: %d\n", compr->device);
 931	snd_iprintf(buffer, "stream: %s\n",
 932			compr->direction == SND_COMPRESS_PLAYBACK
 933				? "PLAYBACK" : "CAPTURE");
 934	snd_iprintf(buffer, "id: %s\n", compr->id);
 935}
 936
 937static int snd_compress_proc_init(struct snd_compr *compr)
 938{
 939	struct snd_info_entry *entry;
 940	char name[16];
 941
 942	sprintf(name, "compr%i", compr->device);
 943	entry = snd_info_create_card_entry(compr->card, name,
 944					   compr->card->proc_root);
 945	if (!entry)
 946		return -ENOMEM;
 947	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
 948	if (snd_info_register(entry) < 0) {
 949		snd_info_free_entry(entry);
 950		return -ENOMEM;
 951	}
 952	compr->proc_root = entry;
 953
 954	entry = snd_info_create_card_entry(compr->card, "info",
 955					   compr->proc_root);
 956	if (entry) {
 957		snd_info_set_text_ops(entry, compr,
 958				      snd_compress_proc_info_read);
 959		if (snd_info_register(entry) < 0) {
 960			snd_info_free_entry(entry);
 961			entry = NULL;
 962		}
 963	}
 964	compr->proc_info_entry = entry;
 965
 966	return 0;
 967}
 968
 969static void snd_compress_proc_done(struct snd_compr *compr)
 970{
 971	snd_info_free_entry(compr->proc_info_entry);
 972	compr->proc_info_entry = NULL;
 973	snd_info_free_entry(compr->proc_root);
 974	compr->proc_root = NULL;
 975}
 976
 977static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
 978{
 979	strlcpy(compr->id, id, sizeof(compr->id));
 980}
 981#else
 982static inline int snd_compress_proc_init(struct snd_compr *compr)
 983{
 984	return 0;
 985}
 986
 987static inline void snd_compress_proc_done(struct snd_compr *compr)
 988{
 989}
 990
 991static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
 992{
 993}
 994#endif
 995
 996static int snd_compress_dev_free(struct snd_device *device)
 997{
 998	struct snd_compr *compr;
 999
1000	compr = device->device_data;
1001	snd_compress_proc_done(compr);
1002	put_device(&compr->dev);
1003	return 0;
1004}
1005
1006/*
1007 * snd_compress_new: create new compress device
1008 * @card: sound card pointer
1009 * @device: device number
1010 * @dirn: device direction, should be of type enum snd_compr_direction
1011 * @compr: compress device pointer
1012 */
1013int snd_compress_new(struct snd_card *card, int device,
1014			int dirn, const char *id, struct snd_compr *compr)
1015{
1016	static struct snd_device_ops ops = {
1017		.dev_free = snd_compress_dev_free,
1018		.dev_register = snd_compress_dev_register,
1019		.dev_disconnect = snd_compress_dev_disconnect,
1020	};
1021	int ret;
1022
1023	compr->card = card;
1024	compr->device = device;
1025	compr->direction = dirn;
1026
1027	snd_compress_set_id(compr, id);
1028
1029	snd_device_initialize(&compr->dev, card);
1030	dev_set_name(&compr->dev, "comprC%iD%i", card->number, device);
1031
1032	ret = snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
1033	if (ret == 0)
1034		snd_compress_proc_init(compr);
1035
1036	return ret;
1037}
1038EXPORT_SYMBOL_GPL(snd_compress_new);
1039
1040static int snd_compress_add_device(struct snd_compr *device)
1041{
1042	int ret;
1043
1044	if (!device->card)
1045		return -EINVAL;
1046
1047	/* register the card */
1048	ret = snd_card_register(device->card);
1049	if (ret)
1050		goto out;
1051	return 0;
1052
1053out:
1054	pr_err("failed with %d\n", ret);
1055	return ret;
1056
1057}
1058
1059static int snd_compress_remove_device(struct snd_compr *device)
1060{
1061	return snd_card_free(device->card);
1062}
1063
1064/**
1065 * snd_compress_register - register compressed device
1066 *
1067 * @device: compressed device to register
1068 */
1069int snd_compress_register(struct snd_compr *device)
1070{
1071	int retval;
1072
1073	if (device->name == NULL || device->ops == NULL)
1074		return -EINVAL;
1075
1076	pr_debug("Registering compressed device %s\n", device->name);
1077	if (snd_BUG_ON(!device->ops->open))
1078		return -EINVAL;
1079	if (snd_BUG_ON(!device->ops->free))
1080		return -EINVAL;
1081	if (snd_BUG_ON(!device->ops->set_params))
1082		return -EINVAL;
1083	if (snd_BUG_ON(!device->ops->trigger))
1084		return -EINVAL;
1085
1086	mutex_init(&device->lock);
1087
1088	/* register a compressed card */
1089	mutex_lock(&device_mutex);
1090	retval = snd_compress_add_device(device);
1091	mutex_unlock(&device_mutex);
1092	return retval;
1093}
1094EXPORT_SYMBOL_GPL(snd_compress_register);
1095
1096int snd_compress_deregister(struct snd_compr *device)
1097{
1098	pr_debug("Removing compressed device %s\n", device->name);
1099	mutex_lock(&device_mutex);
1100	snd_compress_remove_device(device);
1101	mutex_unlock(&device_mutex);
1102	return 0;
1103}
1104EXPORT_SYMBOL_GPL(snd_compress_deregister);
1105
1106static int __init snd_compress_init(void)
1107{
1108	return 0;
1109}
1110
1111static void __exit snd_compress_exit(void)
1112{
1113}
1114
1115module_init(snd_compress_init);
1116module_exit(snd_compress_exit);
1117
1118MODULE_DESCRIPTION("ALSA Compressed offload framework");
1119MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
1120MODULE_LICENSE("GPL v2");