xref: /linux/sound/core/compress_offload.c (revision 071bf69a0220253a44acb8b2a27f7a262b9a46bf)
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 
63 static DEFINE_MUTEX(device_mutex);
64 
65 struct snd_compr_file {
66 	unsigned long caps;
67 	struct snd_compr_stream stream;
68 };
69 
70 static void error_delayed_work(struct work_struct *work);
71 
72 /*
73  * a note on stream states used:
74  * we use following states in the compressed core
75  * SNDRV_PCM_STATE_OPEN: When stream has been opened.
76  * SNDRV_PCM_STATE_SETUP: When stream has been initialized. This is done by
77  *	calling SNDRV_COMPRESS_SET_PARAMS. Running streams will come to this
78  *	state at stop by calling SNDRV_COMPRESS_STOP, or at end of drain.
79  * SNDRV_PCM_STATE_PREPARED: When a stream has been written to (for
80  *	playback only). User after setting up stream writes the data buffer
81  *	before starting the stream.
82  * SNDRV_PCM_STATE_RUNNING: When stream has been started and is
83  *	decoding/encoding and rendering/capturing data.
84  * SNDRV_PCM_STATE_DRAINING: When stream is draining current data. This is done
85  *	by calling SNDRV_COMPRESS_DRAIN.
86  * SNDRV_PCM_STATE_PAUSED: When stream is paused. This is done by calling
87  *	SNDRV_COMPRESS_PAUSE. It can be stopped or resumed by calling
88  *	SNDRV_COMPRESS_STOP or SNDRV_COMPRESS_RESUME respectively.
89  */
90 static int snd_compr_open(struct inode *inode, struct file *f)
91 {
92 	struct snd_compr *compr;
93 	struct snd_compr_file *data;
94 	struct snd_compr_runtime *runtime;
95 	enum snd_compr_direction dirn;
96 	int maj = imajor(inode);
97 	int ret;
98 
99 	if ((f->f_flags & O_ACCMODE) == O_WRONLY)
100 		dirn = SND_COMPRESS_PLAYBACK;
101 	else if ((f->f_flags & O_ACCMODE) == O_RDONLY)
102 		dirn = SND_COMPRESS_CAPTURE;
103 	else
104 		return -EINVAL;
105 
106 	if (maj == snd_major)
107 		compr = snd_lookup_minor_data(iminor(inode),
108 					SNDRV_DEVICE_TYPE_COMPRESS);
109 	else
110 		return -EBADFD;
111 
112 	if (compr == NULL) {
113 		pr_err("no device data!!!\n");
114 		return -ENODEV;
115 	}
116 
117 	if (dirn != compr->direction) {
118 		pr_err("this device doesn't support this direction\n");
119 		snd_card_unref(compr->card);
120 		return -EINVAL;
121 	}
122 
123 	data = kzalloc(sizeof(*data), GFP_KERNEL);
124 	if (!data) {
125 		snd_card_unref(compr->card);
126 		return -ENOMEM;
127 	}
128 
129 	INIT_DELAYED_WORK(&data->stream.error_work, error_delayed_work);
130 
131 	data->stream.ops = compr->ops;
132 	data->stream.direction = dirn;
133 	data->stream.private_data = compr->private_data;
134 	data->stream.device = compr;
135 	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
136 	if (!runtime) {
137 		kfree(data);
138 		snd_card_unref(compr->card);
139 		return -ENOMEM;
140 	}
141 	runtime->state = SNDRV_PCM_STATE_OPEN;
142 	init_waitqueue_head(&runtime->sleep);
143 	data->stream.runtime = runtime;
144 	f->private_data = (void *)data;
145 	mutex_lock(&compr->lock);
146 	ret = compr->ops->open(&data->stream);
147 	mutex_unlock(&compr->lock);
148 	if (ret) {
149 		kfree(runtime);
150 		kfree(data);
151 	}
152 	snd_card_unref(compr->card);
153 	return ret;
154 }
155 
156 static int snd_compr_free(struct inode *inode, struct file *f)
157 {
158 	struct snd_compr_file *data = f->private_data;
159 	struct snd_compr_runtime *runtime = data->stream.runtime;
160 
161 	cancel_delayed_work_sync(&data->stream.error_work);
162 
163 	switch (runtime->state) {
164 	case SNDRV_PCM_STATE_RUNNING:
165 	case SNDRV_PCM_STATE_DRAINING:
166 	case SNDRV_PCM_STATE_PAUSED:
167 		data->stream.ops->trigger(&data->stream, SNDRV_PCM_TRIGGER_STOP);
168 		break;
169 	default:
170 		break;
171 	}
172 
173 	data->stream.ops->free(&data->stream);
174 	kfree(data->stream.runtime->buffer);
175 	kfree(data->stream.runtime);
176 	kfree(data);
177 	return 0;
178 }
179 
180 static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
181 		struct snd_compr_tstamp *tstamp)
182 {
183 	if (!stream->ops->pointer)
184 		return -ENOTSUPP;
185 	stream->ops->pointer(stream, tstamp);
186 	pr_debug("dsp consumed till %d total %d bytes\n",
187 		tstamp->byte_offset, tstamp->copied_total);
188 	if (stream->direction == SND_COMPRESS_PLAYBACK)
189 		stream->runtime->total_bytes_transferred = tstamp->copied_total;
190 	else
191 		stream->runtime->total_bytes_available = tstamp->copied_total;
192 	return 0;
193 }
194 
195 static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
196 		struct snd_compr_avail *avail)
197 {
198 	memset(avail, 0, sizeof(*avail));
199 	snd_compr_update_tstamp(stream, &avail->tstamp);
200 	/* Still need to return avail even if tstamp can't be filled in */
201 
202 	if (stream->runtime->total_bytes_available == 0 &&
203 			stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
204 			stream->direction == SND_COMPRESS_PLAYBACK) {
205 		pr_debug("detected init and someone forgot to do a write\n");
206 		return stream->runtime->buffer_size;
207 	}
208 	pr_debug("app wrote %lld, DSP consumed %lld\n",
209 			stream->runtime->total_bytes_available,
210 			stream->runtime->total_bytes_transferred);
211 	if (stream->runtime->total_bytes_available ==
212 				stream->runtime->total_bytes_transferred) {
213 		if (stream->direction == SND_COMPRESS_PLAYBACK) {
214 			pr_debug("both pointers are same, returning full avail\n");
215 			return stream->runtime->buffer_size;
216 		} else {
217 			pr_debug("both pointers are same, returning no avail\n");
218 			return 0;
219 		}
220 	}
221 
222 	avail->avail = stream->runtime->total_bytes_available -
223 			stream->runtime->total_bytes_transferred;
224 	if (stream->direction == SND_COMPRESS_PLAYBACK)
225 		avail->avail = stream->runtime->buffer_size - avail->avail;
226 
227 	pr_debug("ret avail as %lld\n", avail->avail);
228 	return avail->avail;
229 }
230 
231 static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
232 {
233 	struct snd_compr_avail avail;
234 
235 	return snd_compr_calc_avail(stream, &avail);
236 }
237 
238 static int
239 snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
240 {
241 	struct snd_compr_avail ioctl_avail;
242 	size_t avail;
243 
244 	avail = snd_compr_calc_avail(stream, &ioctl_avail);
245 	ioctl_avail.avail = avail;
246 
247 	switch (stream->runtime->state) {
248 	case SNDRV_PCM_STATE_OPEN:
249 		return -EBADFD;
250 	case SNDRV_PCM_STATE_XRUN:
251 		return -EPIPE;
252 	default:
253 		break;
254 	}
255 
256 	if (copy_to_user((__u64 __user *)arg,
257 				&ioctl_avail, sizeof(ioctl_avail)))
258 		return -EFAULT;
259 	return 0;
260 }
261 
262 static int snd_compr_write_data(struct snd_compr_stream *stream,
263 	       const char __user *buf, size_t count)
264 {
265 	void *dstn;
266 	size_t copy;
267 	struct snd_compr_runtime *runtime = stream->runtime;
268 	/* 64-bit Modulus */
269 	u64 app_pointer = div64_u64(runtime->total_bytes_available,
270 				    runtime->buffer_size);
271 	app_pointer = runtime->total_bytes_available -
272 		      (app_pointer * runtime->buffer_size);
273 
274 	dstn = runtime->buffer + app_pointer;
275 	pr_debug("copying %ld at %lld\n",
276 			(unsigned long)count, app_pointer);
277 	if (count < runtime->buffer_size - app_pointer) {
278 		if (copy_from_user(dstn, buf, count))
279 			return -EFAULT;
280 	} else {
281 		copy = runtime->buffer_size - app_pointer;
282 		if (copy_from_user(dstn, buf, copy))
283 			return -EFAULT;
284 		if (copy_from_user(runtime->buffer, buf + copy, count - copy))
285 			return -EFAULT;
286 	}
287 	/* if DSP cares, let it know data has been written */
288 	if (stream->ops->ack)
289 		stream->ops->ack(stream, count);
290 	return count;
291 }
292 
293 static ssize_t snd_compr_write(struct file *f, const char __user *buf,
294 		size_t count, loff_t *offset)
295 {
296 	struct snd_compr_file *data = f->private_data;
297 	struct snd_compr_stream *stream;
298 	size_t avail;
299 	int retval;
300 
301 	if (snd_BUG_ON(!data))
302 		return -EFAULT;
303 
304 	stream = &data->stream;
305 	mutex_lock(&stream->device->lock);
306 	/* write is allowed when stream is running or has been steup */
307 	switch (stream->runtime->state) {
308 	case SNDRV_PCM_STATE_SETUP:
309 	case SNDRV_PCM_STATE_PREPARED:
310 	case SNDRV_PCM_STATE_RUNNING:
311 		break;
312 	default:
313 		mutex_unlock(&stream->device->lock);
314 		return -EBADFD;
315 	}
316 
317 	avail = snd_compr_get_avail(stream);
318 	pr_debug("avail returned %ld\n", (unsigned long)avail);
319 	/* calculate how much we can write to buffer */
320 	if (avail > count)
321 		avail = count;
322 
323 	if (stream->ops->copy) {
324 		char __user* cbuf = (char __user*)buf;
325 		retval = stream->ops->copy(stream, cbuf, avail);
326 	} else {
327 		retval = snd_compr_write_data(stream, buf, avail);
328 	}
329 	if (retval > 0)
330 		stream->runtime->total_bytes_available += retval;
331 
332 	/* while initiating the stream, write should be called before START
333 	 * call, so in setup move state */
334 	if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
335 		stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
336 		pr_debug("stream prepared, Houston we are good to go\n");
337 	}
338 
339 	mutex_unlock(&stream->device->lock);
340 	return retval;
341 }
342 
343 
344 static ssize_t snd_compr_read(struct file *f, char __user *buf,
345 		size_t count, loff_t *offset)
346 {
347 	struct snd_compr_file *data = f->private_data;
348 	struct snd_compr_stream *stream;
349 	size_t avail;
350 	int retval;
351 
352 	if (snd_BUG_ON(!data))
353 		return -EFAULT;
354 
355 	stream = &data->stream;
356 	mutex_lock(&stream->device->lock);
357 
358 	/* read is allowed when stream is running, paused, draining and setup
359 	 * (yes setup is state which we transition to after stop, so if user
360 	 * wants to read data after stop we allow that)
361 	 */
362 	switch (stream->runtime->state) {
363 	case SNDRV_PCM_STATE_OPEN:
364 	case SNDRV_PCM_STATE_PREPARED:
365 	case SNDRV_PCM_STATE_SUSPENDED:
366 	case SNDRV_PCM_STATE_DISCONNECTED:
367 		retval = -EBADFD;
368 		goto out;
369 	case SNDRV_PCM_STATE_XRUN:
370 		retval = -EPIPE;
371 		goto out;
372 	}
373 
374 	avail = snd_compr_get_avail(stream);
375 	pr_debug("avail returned %ld\n", (unsigned long)avail);
376 	/* calculate how much we can read from buffer */
377 	if (avail > count)
378 		avail = count;
379 
380 	if (stream->ops->copy) {
381 		retval = stream->ops->copy(stream, buf, avail);
382 	} else {
383 		retval = -ENXIO;
384 		goto out;
385 	}
386 	if (retval > 0)
387 		stream->runtime->total_bytes_transferred += retval;
388 
389 out:
390 	mutex_unlock(&stream->device->lock);
391 	return retval;
392 }
393 
394 static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
395 {
396 	return -ENXIO;
397 }
398 
399 static inline int snd_compr_get_poll(struct snd_compr_stream *stream)
400 {
401 	if (stream->direction == SND_COMPRESS_PLAYBACK)
402 		return POLLOUT | POLLWRNORM;
403 	else
404 		return POLLIN | POLLRDNORM;
405 }
406 
407 static unsigned int snd_compr_poll(struct file *f, poll_table *wait)
408 {
409 	struct snd_compr_file *data = f->private_data;
410 	struct snd_compr_stream *stream;
411 	size_t avail;
412 	int retval = 0;
413 
414 	if (snd_BUG_ON(!data))
415 		return POLLERR;
416 
417 	stream = &data->stream;
418 
419 	mutex_lock(&stream->device->lock);
420 
421 	switch (stream->runtime->state) {
422 	case SNDRV_PCM_STATE_OPEN:
423 	case SNDRV_PCM_STATE_XRUN:
424 		retval = snd_compr_get_poll(stream) | POLLERR;
425 		goto out;
426 	default:
427 		break;
428 	}
429 
430 	poll_wait(f, &stream->runtime->sleep, wait);
431 
432 	avail = snd_compr_get_avail(stream);
433 	pr_debug("avail is %ld\n", (unsigned long)avail);
434 	/* check if we have at least one fragment to fill */
435 	switch (stream->runtime->state) {
436 	case SNDRV_PCM_STATE_DRAINING:
437 		/* stream has been woken up after drain is complete
438 		 * draining done so set stream state to stopped
439 		 */
440 		retval = snd_compr_get_poll(stream);
441 		stream->runtime->state = SNDRV_PCM_STATE_SETUP;
442 		break;
443 	case SNDRV_PCM_STATE_RUNNING:
444 	case SNDRV_PCM_STATE_PREPARED:
445 	case SNDRV_PCM_STATE_PAUSED:
446 		if (avail >= stream->runtime->fragment_size)
447 			retval = snd_compr_get_poll(stream);
448 		break;
449 	default:
450 		retval = snd_compr_get_poll(stream) | POLLERR;
451 		break;
452 	}
453 out:
454 	mutex_unlock(&stream->device->lock);
455 	return retval;
456 }
457 
458 static int
459 snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
460 {
461 	int retval;
462 	struct snd_compr_caps caps;
463 
464 	if (!stream->ops->get_caps)
465 		return -ENXIO;
466 
467 	memset(&caps, 0, sizeof(caps));
468 	retval = stream->ops->get_caps(stream, &caps);
469 	if (retval)
470 		goto out;
471 	if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
472 		retval = -EFAULT;
473 out:
474 	return retval;
475 }
476 
477 #ifndef COMPR_CODEC_CAPS_OVERFLOW
478 static int
479 snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
480 {
481 	int retval;
482 	struct snd_compr_codec_caps *caps;
483 
484 	if (!stream->ops->get_codec_caps)
485 		return -ENXIO;
486 
487 	caps = kzalloc(sizeof(*caps), GFP_KERNEL);
488 	if (!caps)
489 		return -ENOMEM;
490 
491 	retval = stream->ops->get_codec_caps(stream, caps);
492 	if (retval)
493 		goto out;
494 	if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
495 		retval = -EFAULT;
496 
497 out:
498 	kfree(caps);
499 	return retval;
500 }
501 #endif /* !COMPR_CODEC_CAPS_OVERFLOW */
502 
503 /* revisit this with snd_pcm_preallocate_xxx */
504 static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
505 		struct snd_compr_params *params)
506 {
507 	unsigned int buffer_size;
508 	void *buffer;
509 
510 	buffer_size = params->buffer.fragment_size * params->buffer.fragments;
511 	if (stream->ops->copy) {
512 		buffer = NULL;
513 		/* if copy is defined the driver will be required to copy
514 		 * the data from core
515 		 */
516 	} else {
517 		buffer = kmalloc(buffer_size, GFP_KERNEL);
518 		if (!buffer)
519 			return -ENOMEM;
520 	}
521 	stream->runtime->fragment_size = params->buffer.fragment_size;
522 	stream->runtime->fragments = params->buffer.fragments;
523 	stream->runtime->buffer = buffer;
524 	stream->runtime->buffer_size = buffer_size;
525 	return 0;
526 }
527 
528 static int snd_compress_check_input(struct snd_compr_params *params)
529 {
530 	/* first let's check the buffer parameter's */
531 	if (params->buffer.fragment_size == 0 ||
532 	    params->buffer.fragments > INT_MAX / params->buffer.fragment_size)
533 		return -EINVAL;
534 
535 	/* now codec parameters */
536 	if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
537 		return -EINVAL;
538 
539 	if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
540 		return -EINVAL;
541 
542 	return 0;
543 }
544 
545 static int
546 snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
547 {
548 	struct snd_compr_params *params;
549 	int retval;
550 
551 	if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
552 		/*
553 		 * we should allow parameter change only when stream has been
554 		 * opened not in other cases
555 		 */
556 		params = kmalloc(sizeof(*params), GFP_KERNEL);
557 		if (!params)
558 			return -ENOMEM;
559 		if (copy_from_user(params, (void __user *)arg, sizeof(*params))) {
560 			retval = -EFAULT;
561 			goto out;
562 		}
563 
564 		retval = snd_compress_check_input(params);
565 		if (retval)
566 			goto out;
567 
568 		retval = snd_compr_allocate_buffer(stream, params);
569 		if (retval) {
570 			retval = -ENOMEM;
571 			goto out;
572 		}
573 
574 		retval = stream->ops->set_params(stream, params);
575 		if (retval)
576 			goto out;
577 
578 		stream->metadata_set = false;
579 		stream->next_track = false;
580 
581 		if (stream->direction == SND_COMPRESS_PLAYBACK)
582 			stream->runtime->state = SNDRV_PCM_STATE_SETUP;
583 		else
584 			stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
585 	} else {
586 		return -EPERM;
587 	}
588 out:
589 	kfree(params);
590 	return retval;
591 }
592 
593 static int
594 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
595 {
596 	struct snd_codec *params;
597 	int retval;
598 
599 	if (!stream->ops->get_params)
600 		return -EBADFD;
601 
602 	params = kzalloc(sizeof(*params), GFP_KERNEL);
603 	if (!params)
604 		return -ENOMEM;
605 	retval = stream->ops->get_params(stream, params);
606 	if (retval)
607 		goto out;
608 	if (copy_to_user((char __user *)arg, params, sizeof(*params)))
609 		retval = -EFAULT;
610 
611 out:
612 	kfree(params);
613 	return retval;
614 }
615 
616 static int
617 snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
618 {
619 	struct snd_compr_metadata metadata;
620 	int retval;
621 
622 	if (!stream->ops->get_metadata)
623 		return -ENXIO;
624 
625 	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
626 		return -EFAULT;
627 
628 	retval = stream->ops->get_metadata(stream, &metadata);
629 	if (retval != 0)
630 		return retval;
631 
632 	if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
633 		return -EFAULT;
634 
635 	return 0;
636 }
637 
638 static int
639 snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
640 {
641 	struct snd_compr_metadata metadata;
642 	int retval;
643 
644 	if (!stream->ops->set_metadata)
645 		return -ENXIO;
646 	/*
647 	* we should allow parameter change only when stream has been
648 	* opened not in other cases
649 	*/
650 	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
651 		return -EFAULT;
652 
653 	retval = stream->ops->set_metadata(stream, &metadata);
654 	stream->metadata_set = true;
655 
656 	return retval;
657 }
658 
659 static inline int
660 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
661 {
662 	struct snd_compr_tstamp tstamp = {0};
663 	int ret;
664 
665 	ret = snd_compr_update_tstamp(stream, &tstamp);
666 	if (ret == 0)
667 		ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
668 			&tstamp, sizeof(tstamp)) ? -EFAULT : 0;
669 	return ret;
670 }
671 
672 static int snd_compr_pause(struct snd_compr_stream *stream)
673 {
674 	int retval;
675 
676 	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
677 		return -EPERM;
678 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
679 	if (!retval)
680 		stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
681 	return retval;
682 }
683 
684 static int snd_compr_resume(struct snd_compr_stream *stream)
685 {
686 	int retval;
687 
688 	if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
689 		return -EPERM;
690 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
691 	if (!retval)
692 		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
693 	return retval;
694 }
695 
696 static int snd_compr_start(struct snd_compr_stream *stream)
697 {
698 	int retval;
699 
700 	if (stream->runtime->state != SNDRV_PCM_STATE_PREPARED)
701 		return -EPERM;
702 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
703 	if (!retval)
704 		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
705 	return retval;
706 }
707 
708 static int snd_compr_stop(struct snd_compr_stream *stream)
709 {
710 	int retval;
711 
712 	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
713 			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
714 		return -EPERM;
715 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
716 	if (!retval) {
717 		snd_compr_drain_notify(stream);
718 		stream->runtime->total_bytes_available = 0;
719 		stream->runtime->total_bytes_transferred = 0;
720 	}
721 	return retval;
722 }
723 
724 static void error_delayed_work(struct work_struct *work)
725 {
726 	struct snd_compr_stream *stream;
727 
728 	stream = container_of(work, struct snd_compr_stream, error_work.work);
729 
730 	mutex_lock(&stream->device->lock);
731 
732 	stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
733 	wake_up(&stream->runtime->sleep);
734 
735 	mutex_unlock(&stream->device->lock);
736 }
737 
738 /*
739  * snd_compr_stop_error: Report a fatal error on a stream
740  * @stream: pointer to stream
741  * @state: state to transition the stream to
742  *
743  * Stop the stream and set its state.
744  *
745  * Should be called with compressed device lock held.
746  */
747 int snd_compr_stop_error(struct snd_compr_stream *stream,
748 			 snd_pcm_state_t state)
749 {
750 	if (stream->runtime->state == state)
751 		return 0;
752 
753 	stream->runtime->state = state;
754 
755 	pr_debug("Changing state to: %d\n", state);
756 
757 	queue_delayed_work(system_power_efficient_wq, &stream->error_work, 0);
758 
759 	return 0;
760 }
761 EXPORT_SYMBOL_GPL(snd_compr_stop_error);
762 
763 static int snd_compress_wait_for_drain(struct snd_compr_stream *stream)
764 {
765 	int ret;
766 
767 	/*
768 	 * We are called with lock held. So drop the lock while we wait for
769 	 * drain complete notification from the driver
770 	 *
771 	 * It is expected that driver will notify the drain completion and then
772 	 * stream will be moved to SETUP state, even if draining resulted in an
773 	 * error. We can trigger next track after this.
774 	 */
775 	stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
776 	mutex_unlock(&stream->device->lock);
777 
778 	/* we wait for drain to complete here, drain can return when
779 	 * interruption occurred, wait returned error or success.
780 	 * For the first two cases we don't do anything different here and
781 	 * return after waking up
782 	 */
783 
784 	ret = wait_event_interruptible(stream->runtime->sleep,
785 			(stream->runtime->state != SNDRV_PCM_STATE_DRAINING));
786 	if (ret == -ERESTARTSYS)
787 		pr_debug("wait aborted by a signal");
788 	else if (ret)
789 		pr_debug("wait for drain failed with %d\n", ret);
790 
791 
792 	wake_up(&stream->runtime->sleep);
793 	mutex_lock(&stream->device->lock);
794 
795 	return ret;
796 }
797 
798 static int snd_compr_drain(struct snd_compr_stream *stream)
799 {
800 	int retval;
801 
802 	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
803 			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
804 		return -EPERM;
805 
806 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
807 	if (retval) {
808 		pr_debug("SND_COMPR_TRIGGER_DRAIN failed %d\n", retval);
809 		wake_up(&stream->runtime->sleep);
810 		return retval;
811 	}
812 
813 	return snd_compress_wait_for_drain(stream);
814 }
815 
816 static int snd_compr_next_track(struct snd_compr_stream *stream)
817 {
818 	int retval;
819 
820 	/* only a running stream can transition to next track */
821 	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
822 		return -EPERM;
823 
824 	/* you can signal next track if this is intended to be a gapless stream
825 	 * and current track metadata is set
826 	 */
827 	if (stream->metadata_set == false)
828 		return -EPERM;
829 
830 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
831 	if (retval != 0)
832 		return retval;
833 	stream->metadata_set = false;
834 	stream->next_track = true;
835 	return 0;
836 }
837 
838 static int snd_compr_partial_drain(struct snd_compr_stream *stream)
839 {
840 	int retval;
841 	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
842 			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
843 		return -EPERM;
844 	/* stream can be drained only when next track has been signalled */
845 	if (stream->next_track == false)
846 		return -EPERM;
847 
848 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
849 	if (retval) {
850 		pr_debug("Partial drain returned failure\n");
851 		wake_up(&stream->runtime->sleep);
852 		return retval;
853 	}
854 
855 	stream->next_track = false;
856 	return snd_compress_wait_for_drain(stream);
857 }
858 
859 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
860 {
861 	struct snd_compr_file *data = f->private_data;
862 	struct snd_compr_stream *stream;
863 	int retval = -ENOTTY;
864 
865 	if (snd_BUG_ON(!data))
866 		return -EFAULT;
867 
868 	stream = &data->stream;
869 
870 	mutex_lock(&stream->device->lock);
871 	switch (_IOC_NR(cmd)) {
872 	case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
873 		retval = put_user(SNDRV_COMPRESS_VERSION,
874 				(int __user *)arg) ? -EFAULT : 0;
875 		break;
876 	case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
877 		retval = snd_compr_get_caps(stream, arg);
878 		break;
879 #ifndef COMPR_CODEC_CAPS_OVERFLOW
880 	case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
881 		retval = snd_compr_get_codec_caps(stream, arg);
882 		break;
883 #endif
884 	case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
885 		retval = snd_compr_set_params(stream, arg);
886 		break;
887 	case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
888 		retval = snd_compr_get_params(stream, arg);
889 		break;
890 	case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
891 		retval = snd_compr_set_metadata(stream, arg);
892 		break;
893 	case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
894 		retval = snd_compr_get_metadata(stream, arg);
895 		break;
896 	case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
897 		retval = snd_compr_tstamp(stream, arg);
898 		break;
899 	case _IOC_NR(SNDRV_COMPRESS_AVAIL):
900 		retval = snd_compr_ioctl_avail(stream, arg);
901 		break;
902 	case _IOC_NR(SNDRV_COMPRESS_PAUSE):
903 		retval = snd_compr_pause(stream);
904 		break;
905 	case _IOC_NR(SNDRV_COMPRESS_RESUME):
906 		retval = snd_compr_resume(stream);
907 		break;
908 	case _IOC_NR(SNDRV_COMPRESS_START):
909 		retval = snd_compr_start(stream);
910 		break;
911 	case _IOC_NR(SNDRV_COMPRESS_STOP):
912 		retval = snd_compr_stop(stream);
913 		break;
914 	case _IOC_NR(SNDRV_COMPRESS_DRAIN):
915 		retval = snd_compr_drain(stream);
916 		break;
917 	case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
918 		retval = snd_compr_partial_drain(stream);
919 		break;
920 	case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
921 		retval = snd_compr_next_track(stream);
922 		break;
923 
924 	}
925 	mutex_unlock(&stream->device->lock);
926 	return retval;
927 }
928 
929 /* support of 32bit userspace on 64bit platforms */
930 #ifdef CONFIG_COMPAT
931 static long snd_compr_ioctl_compat(struct file *file, unsigned int cmd,
932 						unsigned long arg)
933 {
934 	return snd_compr_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
935 }
936 #endif
937 
938 static const struct file_operations snd_compr_file_ops = {
939 		.owner =	THIS_MODULE,
940 		.open =		snd_compr_open,
941 		.release =	snd_compr_free,
942 		.write =	snd_compr_write,
943 		.read =		snd_compr_read,
944 		.unlocked_ioctl = snd_compr_ioctl,
945 #ifdef CONFIG_COMPAT
946 		.compat_ioctl = snd_compr_ioctl_compat,
947 #endif
948 		.mmap =		snd_compr_mmap,
949 		.poll =		snd_compr_poll,
950 };
951 
952 static int snd_compress_dev_register(struct snd_device *device)
953 {
954 	int ret = -EINVAL;
955 	char str[16];
956 	struct snd_compr *compr;
957 
958 	if (snd_BUG_ON(!device || !device->device_data))
959 		return -EBADFD;
960 	compr = device->device_data;
961 
962 	pr_debug("reg %s for device %s, direction %d\n", str, compr->name,
963 			compr->direction);
964 	/* register compressed device */
965 	ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS,
966 				  compr->card, compr->device,
967 				  &snd_compr_file_ops, compr, &compr->dev);
968 	if (ret < 0) {
969 		pr_err("snd_register_device failed\n %d", ret);
970 		return ret;
971 	}
972 	return ret;
973 
974 }
975 
976 static int snd_compress_dev_disconnect(struct snd_device *device)
977 {
978 	struct snd_compr *compr;
979 
980 	compr = device->device_data;
981 	snd_unregister_device(&compr->dev);
982 	return 0;
983 }
984 
985 #ifdef CONFIG_SND_VERBOSE_PROCFS
986 static void snd_compress_proc_info_read(struct snd_info_entry *entry,
987 					struct snd_info_buffer *buffer)
988 {
989 	struct snd_compr *compr = (struct snd_compr *)entry->private_data;
990 
991 	snd_iprintf(buffer, "card: %d\n", compr->card->number);
992 	snd_iprintf(buffer, "device: %d\n", compr->device);
993 	snd_iprintf(buffer, "stream: %s\n",
994 			compr->direction == SND_COMPRESS_PLAYBACK
995 				? "PLAYBACK" : "CAPTURE");
996 	snd_iprintf(buffer, "id: %s\n", compr->id);
997 }
998 
999 static int snd_compress_proc_init(struct snd_compr *compr)
1000 {
1001 	struct snd_info_entry *entry;
1002 	char name[16];
1003 
1004 	sprintf(name, "compr%i", compr->device);
1005 	entry = snd_info_create_card_entry(compr->card, name,
1006 					   compr->card->proc_root);
1007 	if (!entry)
1008 		return -ENOMEM;
1009 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
1010 	if (snd_info_register(entry) < 0) {
1011 		snd_info_free_entry(entry);
1012 		return -ENOMEM;
1013 	}
1014 	compr->proc_root = entry;
1015 
1016 	entry = snd_info_create_card_entry(compr->card, "info",
1017 					   compr->proc_root);
1018 	if (entry) {
1019 		snd_info_set_text_ops(entry, compr,
1020 				      snd_compress_proc_info_read);
1021 		if (snd_info_register(entry) < 0) {
1022 			snd_info_free_entry(entry);
1023 			entry = NULL;
1024 		}
1025 	}
1026 	compr->proc_info_entry = entry;
1027 
1028 	return 0;
1029 }
1030 
1031 static void snd_compress_proc_done(struct snd_compr *compr)
1032 {
1033 	snd_info_free_entry(compr->proc_info_entry);
1034 	compr->proc_info_entry = NULL;
1035 	snd_info_free_entry(compr->proc_root);
1036 	compr->proc_root = NULL;
1037 }
1038 
1039 static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
1040 {
1041 	strlcpy(compr->id, id, sizeof(compr->id));
1042 }
1043 #else
1044 static inline int snd_compress_proc_init(struct snd_compr *compr)
1045 {
1046 	return 0;
1047 }
1048 
1049 static inline void snd_compress_proc_done(struct snd_compr *compr)
1050 {
1051 }
1052 
1053 static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
1054 {
1055 }
1056 #endif
1057 
1058 static int snd_compress_dev_free(struct snd_device *device)
1059 {
1060 	struct snd_compr *compr;
1061 
1062 	compr = device->device_data;
1063 	snd_compress_proc_done(compr);
1064 	put_device(&compr->dev);
1065 	return 0;
1066 }
1067 
1068 /*
1069  * snd_compress_new: create new compress device
1070  * @card: sound card pointer
1071  * @device: device number
1072  * @dirn: device direction, should be of type enum snd_compr_direction
1073  * @compr: compress device pointer
1074  */
1075 int snd_compress_new(struct snd_card *card, int device,
1076 			int dirn, const char *id, struct snd_compr *compr)
1077 {
1078 	static struct snd_device_ops ops = {
1079 		.dev_free = snd_compress_dev_free,
1080 		.dev_register = snd_compress_dev_register,
1081 		.dev_disconnect = snd_compress_dev_disconnect,
1082 	};
1083 	int ret;
1084 
1085 	compr->card = card;
1086 	compr->device = device;
1087 	compr->direction = dirn;
1088 
1089 	snd_compress_set_id(compr, id);
1090 
1091 	snd_device_initialize(&compr->dev, card);
1092 	dev_set_name(&compr->dev, "comprC%iD%i", card->number, device);
1093 
1094 	ret = snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
1095 	if (ret == 0)
1096 		snd_compress_proc_init(compr);
1097 
1098 	return ret;
1099 }
1100 EXPORT_SYMBOL_GPL(snd_compress_new);
1101 
1102 static int snd_compress_add_device(struct snd_compr *device)
1103 {
1104 	int ret;
1105 
1106 	if (!device->card)
1107 		return -EINVAL;
1108 
1109 	/* register the card */
1110 	ret = snd_card_register(device->card);
1111 	if (ret)
1112 		goto out;
1113 	return 0;
1114 
1115 out:
1116 	pr_err("failed with %d\n", ret);
1117 	return ret;
1118 
1119 }
1120 
1121 static int snd_compress_remove_device(struct snd_compr *device)
1122 {
1123 	return snd_card_free(device->card);
1124 }
1125 
1126 /**
1127  * snd_compress_register - register compressed device
1128  *
1129  * @device: compressed device to register
1130  */
1131 int snd_compress_register(struct snd_compr *device)
1132 {
1133 	int retval;
1134 
1135 	if (device->name == NULL || device->ops == NULL)
1136 		return -EINVAL;
1137 
1138 	pr_debug("Registering compressed device %s\n", device->name);
1139 	if (snd_BUG_ON(!device->ops->open))
1140 		return -EINVAL;
1141 	if (snd_BUG_ON(!device->ops->free))
1142 		return -EINVAL;
1143 	if (snd_BUG_ON(!device->ops->set_params))
1144 		return -EINVAL;
1145 	if (snd_BUG_ON(!device->ops->trigger))
1146 		return -EINVAL;
1147 
1148 	mutex_init(&device->lock);
1149 
1150 	/* register a compressed card */
1151 	mutex_lock(&device_mutex);
1152 	retval = snd_compress_add_device(device);
1153 	mutex_unlock(&device_mutex);
1154 	return retval;
1155 }
1156 EXPORT_SYMBOL_GPL(snd_compress_register);
1157 
1158 int snd_compress_deregister(struct snd_compr *device)
1159 {
1160 	pr_debug("Removing compressed device %s\n", device->name);
1161 	mutex_lock(&device_mutex);
1162 	snd_compress_remove_device(device);
1163 	mutex_unlock(&device_mutex);
1164 	return 0;
1165 }
1166 EXPORT_SYMBOL_GPL(snd_compress_deregister);
1167 
1168 static int __init snd_compress_init(void)
1169 {
1170 	return 0;
1171 }
1172 
1173 static void __exit snd_compress_exit(void)
1174 {
1175 }
1176 
1177 module_init(snd_compress_init);
1178 module_exit(snd_compress_exit);
1179 
1180 MODULE_DESCRIPTION("ALSA Compressed offload framework");
1181 MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
1182 MODULE_LICENSE("GPL v2");
1183