ALSA: Fix memory leak on error in snd_compr_set_params()
[linux-2.6.git] / sound / core / compress_offload.c
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/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>
44
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
50  */
51
52 static DEFINE_MUTEX(device_mutex);
53
54 struct snd_compr_file {
55         unsigned long caps;
56         struct snd_compr_stream stream;
57 };
58
59 /*
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.
73  */
74 static int snd_compr_open(struct inode *inode, struct file *f)
75 {
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;
82
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;
90         }
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                 return -EINVAL;
106         }
107
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;
119         }
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);
130         }
131         return ret;
132 }
133
134 static int snd_compr_free(struct inode *inode, struct file *f)
135 {
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;
142 }
143
144 static void snd_compr_update_tstamp(struct snd_compr_stream *stream,
145                 struct snd_compr_tstamp *tstamp)
146 {
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;
154 }
155
156 static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
157                 struct snd_compr_avail *avail)
158 {
159         long avail_calc; /*this needs to be signed variable */
160
161         snd_compr_update_tstamp(stream, &avail->tstamp);
162
163         /* FIXME: This needs to be different for capture stream,
164            available is # of compressed data, for playback it's
165            remainder of buffer */
166
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;
171         }
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;
179         }
180
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 */
186
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;
197 }
198
199 static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
200 {
201         struct snd_compr_avail avail;
202
203         return snd_compr_calc_avail(stream, &avail);
204 }
205
206 static int
207 snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
208 {
209         struct snd_compr_avail ioctl_avail;
210         size_t avail;
211
212         avail = snd_compr_calc_avail(stream, &ioctl_avail);
213         ioctl_avail.avail = avail;
214
215         if (copy_to_user((__u64 __user *)arg,
216                                 &ioctl_avail, sizeof(ioctl_avail)))
217                 return -EFAULT;
218         return 0;
219 }
220
221 static int snd_compr_write_data(struct snd_compr_stream *stream,
222                const char __user *buf, size_t count)
223 {
224         void *dstn;
225         size_t copy;
226         struct snd_compr_runtime *runtime = stream->runtime;
227
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;
242         }
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;
247 }
248
249 static ssize_t snd_compr_write(struct file *f, const char __user *buf,
250                 size_t count, loff_t *offset)
251 {
252         struct snd_compr_file *data = f->private_data;
253         struct snd_compr_stream *stream;
254         size_t avail;
255         int retval;
256
257         if (snd_BUG_ON(!data))
258                 return -EFAULT;
259
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;
267         }
268
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;
274
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;
281
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");
287         }
288
289         mutex_unlock(&stream->device->lock);
290         return retval;
291 }
292
293
294 static ssize_t snd_compr_read(struct file *f, char __user *buf,
295                 size_t count, loff_t *offset)
296 {
297         return -ENXIO;
298 }
299
300 static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
301 {
302         return -ENXIO;
303 }
304
305 static inline int snd_compr_get_poll(struct snd_compr_stream *stream)
306 {
307         if (stream->direction == SND_COMPRESS_PLAYBACK)
308                 return POLLOUT | POLLWRNORM;
309         else
310                 return POLLIN | POLLRDNORM;
311 }
312
313 static unsigned int snd_compr_poll(struct file *f, poll_table *wait)
314 {
315         struct snd_compr_file *data = f->private_data;
316         struct snd_compr_stream *stream;
317         size_t avail;
318         int retval = 0;
319
320         if (snd_BUG_ON(!data))
321                 return -EFAULT;
322         stream = &data->stream;
323         if (snd_BUG_ON(!stream))
324                 return -EFAULT;
325
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;
331         }
332         poll_wait(f, &stream->runtime->sleep, wait);
333
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
341                  */
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;
357         }
358 out:
359         mutex_unlock(&stream->device->lock);
360         return retval;
361 }
362
363 static int
364 snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
365 {
366         int retval;
367         struct snd_compr_caps caps;
368
369         if (!stream->ops->get_caps)
370                 return -ENXIO;
371
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;
379 }
380
381 static int
382 snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
383 {
384         int retval;
385         struct snd_compr_codec_caps *caps;
386
387         if (!stream->ops->get_codec_caps)
388                 return -ENXIO;
389
390         caps = kmalloc(sizeof(*caps), GFP_KERNEL);
391         if (!caps)
392                 return -ENOMEM;
393
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;
399
400 out:
401         kfree(caps);
402         return retval;
403 }
404
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)
408 {
409         unsigned int buffer_size;
410         void *buffer;
411
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
417                  */
418         } else {
419                 buffer = kmalloc(buffer_size, GFP_KERNEL);
420                 if (!buffer)
421                         return -ENOMEM;
422         }
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;
428 }
429
430 static int
431 snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
432 {
433         struct snd_compr_params *params;
434         int retval;
435
436         if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
437                 /*
438                  * we should allow parameter change only when stream has been
439                  * opened not in other cases
440                  */
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;
447                 }
448                 retval = snd_compr_allocate_buffer(stream, params);
449                 if (retval) {
450                         retval = -ENOMEM;
451                         goto out;
452                 }
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;
459         }
460 out:
461         kfree(params);
462         return retval;
463 }
464
465 static int
466 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
467 {
468         struct snd_codec *params;
469         int retval;
470
471         if (!stream->ops->get_params)
472                 return -EBADFD;
473
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;
482
483 out:
484         kfree(params);
485         return retval;
486 }
487
488 static inline int
489 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
490 {
491         struct snd_compr_tstamp tstamp;
492
493         snd_compr_update_tstamp(stream, &tstamp);
494         return copy_to_user((struct snd_compr_tstamp __user *)arg,
495                 &tstamp, sizeof(tstamp)) ? -EFAULT : 0;
496 }
497
498 static int snd_compr_pause(struct snd_compr_stream *stream)
499 {
500         int retval;
501
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);
508         }
509         return retval;
510 }
511
512 static int snd_compr_resume(struct snd_compr_stream *stream)
513 {
514         int retval;
515
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;
522 }
523
524 static int snd_compr_start(struct snd_compr_stream *stream)
525 {
526         int retval;
527
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;
534 }
535
536 static int snd_compr_stop(struct snd_compr_stream *stream)
537 {
538         int retval;
539
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);
547         }
548         return retval;
549 }
550
551 static int snd_compr_drain(struct snd_compr_stream *stream)
552 {
553         int retval;
554
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);
562         }
563         return retval;
564 }
565
566 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
567 {
568         struct snd_compr_file *data = f->private_data;
569         struct snd_compr_stream *stream;
570         int retval = -ENOTTY;
571
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;
616         }
617         mutex_unlock(&stream->device->lock);
618         return retval;
619 }
620
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,
630 };
631
632 static int snd_compress_dev_register(struct snd_device *device)
633 {
634         int ret = -EINVAL;
635         char str[16];
636         struct snd_compr *compr;
637
638         if (snd_BUG_ON(!device || !device->device_data))
639                 return -EBADFD;
640         compr = device->device_data;
641
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;
651         }
652         return ret;
653
654 }
655
656 static int snd_compress_dev_disconnect(struct snd_device *device)
657 {
658         struct snd_compr *compr;
659
660         compr = device->device_data;
661         snd_unregister_device(compr->direction, compr->card, compr->device);
662         return 0;
663 }
664
665 /*
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
671  */
672 int snd_compress_new(struct snd_card *card, int device,
673                         int dirn, struct snd_compr *compr)
674 {
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,
679         };
680
681         compr->card = card;
682         compr->device = device;
683         compr->direction = dirn;
684         return snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
685 }
686 EXPORT_SYMBOL_GPL(snd_compress_new);
687
688 static int snd_compress_add_device(struct snd_compr *device)
689 {
690         int ret;
691
692         if (!device->card)
693                 return -EINVAL;
694
695         /* register the card */
696         ret = snd_card_register(device->card);
697         if (ret)
698                 goto out;
699         return 0;
700
701 out:
702         pr_err("failed with %d\n", ret);
703         return ret;
704
705 }
706
707 static int snd_compress_remove_device(struct snd_compr *device)
708 {
709         return snd_card_free(device->card);
710 }
711
712 /**
713  * snd_compress_register - register compressed device
714  *
715  * @device: compressed device to register
716  */
717 int snd_compress_register(struct snd_compr *device)
718 {
719         int retval;
720
721         if (device->name == NULL || device->dev == NULL || device->ops == NULL)
722                 return -EINVAL;
723
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;
733
734         mutex_init(&device->lock);
735
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;
741 }
742 EXPORT_SYMBOL_GPL(snd_compress_register);
743
744 int snd_compress_deregister(struct snd_compr *device)
745 {
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;
751 }
752 EXPORT_SYMBOL_GPL(snd_compress_deregister);
753
754 static int __init snd_compress_init(void)
755 {
756         return 0;
757 }
758
759 static void __exit snd_compress_exit(void)
760 {
761 }
762
763 module_init(snd_compress_init);
764 module_exit(snd_compress_exit);
765
766 MODULE_DESCRIPTION("ALSA Compressed offload framework");
767 MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
768 MODULE_LICENSE("GPL v2");