xref: /openbmc/linux/sound/core/compress_offload.c (revision addee42a)
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 __poll_t snd_compr_get_poll(struct snd_compr_stream *stream)
400 {
401 	if (stream->direction == SND_COMPRESS_PLAYBACK)
402 		return EPOLLOUT | EPOLLWRNORM;
403 	else
404 		return EPOLLIN | EPOLLRDNORM;
405 }
406 
407 static __poll_t 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 	__poll_t retval = 0;
413 
414 	if (snd_BUG_ON(!data))
415 		return EPOLLERR;
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) | EPOLLERR;
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) | EPOLLERR;
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 = memdup_user((void __user *)arg, sizeof(*params));
557 		if (IS_ERR(params))
558 			return PTR_ERR(params);
559 
560 		retval = snd_compress_check_input(params);
561 		if (retval)
562 			goto out;
563 
564 		retval = snd_compr_allocate_buffer(stream, params);
565 		if (retval) {
566 			retval = -ENOMEM;
567 			goto out;
568 		}
569 
570 		retval = stream->ops->set_params(stream, params);
571 		if (retval)
572 			goto out;
573 
574 		stream->metadata_set = false;
575 		stream->next_track = false;
576 
577 		if (stream->direction == SND_COMPRESS_PLAYBACK)
578 			stream->runtime->state = SNDRV_PCM_STATE_SETUP;
579 		else
580 			stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
581 	} else {
582 		return -EPERM;
583 	}
584 out:
585 	kfree(params);
586 	return retval;
587 }
588 
589 static int
590 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
591 {
592 	struct snd_codec *params;
593 	int retval;
594 
595 	if (!stream->ops->get_params)
596 		return -EBADFD;
597 
598 	params = kzalloc(sizeof(*params), GFP_KERNEL);
599 	if (!params)
600 		return -ENOMEM;
601 	retval = stream->ops->get_params(stream, params);
602 	if (retval)
603 		goto out;
604 	if (copy_to_user((char __user *)arg, params, sizeof(*params)))
605 		retval = -EFAULT;
606 
607 out:
608 	kfree(params);
609 	return retval;
610 }
611 
612 static int
613 snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
614 {
615 	struct snd_compr_metadata metadata;
616 	int retval;
617 
618 	if (!stream->ops->get_metadata)
619 		return -ENXIO;
620 
621 	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
622 		return -EFAULT;
623 
624 	retval = stream->ops->get_metadata(stream, &metadata);
625 	if (retval != 0)
626 		return retval;
627 
628 	if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
629 		return -EFAULT;
630 
631 	return 0;
632 }
633 
634 static int
635 snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
636 {
637 	struct snd_compr_metadata metadata;
638 	int retval;
639 
640 	if (!stream->ops->set_metadata)
641 		return -ENXIO;
642 	/*
643 	* we should allow parameter change only when stream has been
644 	* opened not in other cases
645 	*/
646 	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
647 		return -EFAULT;
648 
649 	retval = stream->ops->set_metadata(stream, &metadata);
650 	stream->metadata_set = true;
651 
652 	return retval;
653 }
654 
655 static inline int
656 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
657 {
658 	struct snd_compr_tstamp tstamp = {0};
659 	int ret;
660 
661 	ret = snd_compr_update_tstamp(stream, &tstamp);
662 	if (ret == 0)
663 		ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
664 			&tstamp, sizeof(tstamp)) ? -EFAULT : 0;
665 	return ret;
666 }
667 
668 static int snd_compr_pause(struct snd_compr_stream *stream)
669 {
670 	int retval;
671 
672 	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
673 		return -EPERM;
674 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
675 	if (!retval)
676 		stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
677 	return retval;
678 }
679 
680 static int snd_compr_resume(struct snd_compr_stream *stream)
681 {
682 	int retval;
683 
684 	if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
685 		return -EPERM;
686 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
687 	if (!retval)
688 		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
689 	return retval;
690 }
691 
692 static int snd_compr_start(struct snd_compr_stream *stream)
693 {
694 	int retval;
695 
696 	if (stream->runtime->state != SNDRV_PCM_STATE_PREPARED)
697 		return -EPERM;
698 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
699 	if (!retval)
700 		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
701 	return retval;
702 }
703 
704 static int snd_compr_stop(struct snd_compr_stream *stream)
705 {
706 	int retval;
707 
708 	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
709 			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
710 		return -EPERM;
711 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
712 	if (!retval) {
713 		snd_compr_drain_notify(stream);
714 		stream->runtime->total_bytes_available = 0;
715 		stream->runtime->total_bytes_transferred = 0;
716 	}
717 	return retval;
718 }
719 
720 static void error_delayed_work(struct work_struct *work)
721 {
722 	struct snd_compr_stream *stream;
723 
724 	stream = container_of(work, struct snd_compr_stream, error_work.work);
725 
726 	mutex_lock(&stream->device->lock);
727 
728 	stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
729 	wake_up(&stream->runtime->sleep);
730 
731 	mutex_unlock(&stream->device->lock);
732 }
733 
734 /*
735  * snd_compr_stop_error: Report a fatal error on a stream
736  * @stream: pointer to stream
737  * @state: state to transition the stream to
738  *
739  * Stop the stream and set its state.
740  *
741  * Should be called with compressed device lock held.
742  */
743 int snd_compr_stop_error(struct snd_compr_stream *stream,
744 			 snd_pcm_state_t state)
745 {
746 	if (stream->runtime->state == state)
747 		return 0;
748 
749 	stream->runtime->state = state;
750 
751 	pr_debug("Changing state to: %d\n", state);
752 
753 	queue_delayed_work(system_power_efficient_wq, &stream->error_work, 0);
754 
755 	return 0;
756 }
757 EXPORT_SYMBOL_GPL(snd_compr_stop_error);
758 
759 static int snd_compress_wait_for_drain(struct snd_compr_stream *stream)
760 {
761 	int ret;
762 
763 	/*
764 	 * We are called with lock held. So drop the lock while we wait for
765 	 * drain complete notification from the driver
766 	 *
767 	 * It is expected that driver will notify the drain completion and then
768 	 * stream will be moved to SETUP state, even if draining resulted in an
769 	 * error. We can trigger next track after this.
770 	 */
771 	stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
772 	mutex_unlock(&stream->device->lock);
773 
774 	/* we wait for drain to complete here, drain can return when
775 	 * interruption occurred, wait returned error or success.
776 	 * For the first two cases we don't do anything different here and
777 	 * return after waking up
778 	 */
779 
780 	ret = wait_event_interruptible(stream->runtime->sleep,
781 			(stream->runtime->state != SNDRV_PCM_STATE_DRAINING));
782 	if (ret == -ERESTARTSYS)
783 		pr_debug("wait aborted by a signal\n");
784 	else if (ret)
785 		pr_debug("wait for drain failed with %d\n", ret);
786 
787 
788 	wake_up(&stream->runtime->sleep);
789 	mutex_lock(&stream->device->lock);
790 
791 	return ret;
792 }
793 
794 static int snd_compr_drain(struct snd_compr_stream *stream)
795 {
796 	int retval;
797 
798 	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
799 			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
800 		return -EPERM;
801 
802 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
803 	if (retval) {
804 		pr_debug("SND_COMPR_TRIGGER_DRAIN failed %d\n", retval);
805 		wake_up(&stream->runtime->sleep);
806 		return retval;
807 	}
808 
809 	return snd_compress_wait_for_drain(stream);
810 }
811 
812 static int snd_compr_next_track(struct snd_compr_stream *stream)
813 {
814 	int retval;
815 
816 	/* only a running stream can transition to next track */
817 	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
818 		return -EPERM;
819 
820 	/* you can signal next track if this is intended to be a gapless stream
821 	 * and current track metadata is set
822 	 */
823 	if (stream->metadata_set == false)
824 		return -EPERM;
825 
826 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
827 	if (retval != 0)
828 		return retval;
829 	stream->metadata_set = false;
830 	stream->next_track = true;
831 	return 0;
832 }
833 
834 static int snd_compr_partial_drain(struct snd_compr_stream *stream)
835 {
836 	int retval;
837 	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
838 			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
839 		return -EPERM;
840 	/* stream can be drained only when next track has been signalled */
841 	if (stream->next_track == false)
842 		return -EPERM;
843 
844 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
845 	if (retval) {
846 		pr_debug("Partial drain returned failure\n");
847 		wake_up(&stream->runtime->sleep);
848 		return retval;
849 	}
850 
851 	stream->next_track = false;
852 	return snd_compress_wait_for_drain(stream);
853 }
854 
855 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
856 {
857 	struct snd_compr_file *data = f->private_data;
858 	struct snd_compr_stream *stream;
859 	int retval = -ENOTTY;
860 
861 	if (snd_BUG_ON(!data))
862 		return -EFAULT;
863 
864 	stream = &data->stream;
865 
866 	mutex_lock(&stream->device->lock);
867 	switch (_IOC_NR(cmd)) {
868 	case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
869 		retval = put_user(SNDRV_COMPRESS_VERSION,
870 				(int __user *)arg) ? -EFAULT : 0;
871 		break;
872 	case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
873 		retval = snd_compr_get_caps(stream, arg);
874 		break;
875 #ifndef COMPR_CODEC_CAPS_OVERFLOW
876 	case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
877 		retval = snd_compr_get_codec_caps(stream, arg);
878 		break;
879 #endif
880 	case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
881 		retval = snd_compr_set_params(stream, arg);
882 		break;
883 	case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
884 		retval = snd_compr_get_params(stream, arg);
885 		break;
886 	case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
887 		retval = snd_compr_set_metadata(stream, arg);
888 		break;
889 	case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
890 		retval = snd_compr_get_metadata(stream, arg);
891 		break;
892 	case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
893 		retval = snd_compr_tstamp(stream, arg);
894 		break;
895 	case _IOC_NR(SNDRV_COMPRESS_AVAIL):
896 		retval = snd_compr_ioctl_avail(stream, arg);
897 		break;
898 	case _IOC_NR(SNDRV_COMPRESS_PAUSE):
899 		retval = snd_compr_pause(stream);
900 		break;
901 	case _IOC_NR(SNDRV_COMPRESS_RESUME):
902 		retval = snd_compr_resume(stream);
903 		break;
904 	case _IOC_NR(SNDRV_COMPRESS_START):
905 		retval = snd_compr_start(stream);
906 		break;
907 	case _IOC_NR(SNDRV_COMPRESS_STOP):
908 		retval = snd_compr_stop(stream);
909 		break;
910 	case _IOC_NR(SNDRV_COMPRESS_DRAIN):
911 		retval = snd_compr_drain(stream);
912 		break;
913 	case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
914 		retval = snd_compr_partial_drain(stream);
915 		break;
916 	case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
917 		retval = snd_compr_next_track(stream);
918 		break;
919 
920 	}
921 	mutex_unlock(&stream->device->lock);
922 	return retval;
923 }
924 
925 /* support of 32bit userspace on 64bit platforms */
926 #ifdef CONFIG_COMPAT
927 static long snd_compr_ioctl_compat(struct file *file, unsigned int cmd,
928 						unsigned long arg)
929 {
930 	return snd_compr_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
931 }
932 #endif
933 
934 static const struct file_operations snd_compr_file_ops = {
935 		.owner =	THIS_MODULE,
936 		.open =		snd_compr_open,
937 		.release =	snd_compr_free,
938 		.write =	snd_compr_write,
939 		.read =		snd_compr_read,
940 		.unlocked_ioctl = snd_compr_ioctl,
941 #ifdef CONFIG_COMPAT
942 		.compat_ioctl = snd_compr_ioctl_compat,
943 #endif
944 		.mmap =		snd_compr_mmap,
945 		.poll =		snd_compr_poll,
946 };
947 
948 static int snd_compress_dev_register(struct snd_device *device)
949 {
950 	int ret = -EINVAL;
951 	struct snd_compr *compr;
952 
953 	if (snd_BUG_ON(!device || !device->device_data))
954 		return -EBADFD;
955 	compr = device->device_data;
956 
957 	pr_debug("reg device %s, direction %d\n", compr->name,
958 			compr->direction);
959 	/* register compressed device */
960 	ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS,
961 				  compr->card, compr->device,
962 				  &snd_compr_file_ops, compr, &compr->dev);
963 	if (ret < 0) {
964 		pr_err("snd_register_device failed %d\n", ret);
965 		return ret;
966 	}
967 	return ret;
968 
969 }
970 
971 static int snd_compress_dev_disconnect(struct snd_device *device)
972 {
973 	struct snd_compr *compr;
974 
975 	compr = device->device_data;
976 	snd_unregister_device(&compr->dev);
977 	return 0;
978 }
979 
980 #ifdef CONFIG_SND_VERBOSE_PROCFS
981 static void snd_compress_proc_info_read(struct snd_info_entry *entry,
982 					struct snd_info_buffer *buffer)
983 {
984 	struct snd_compr *compr = (struct snd_compr *)entry->private_data;
985 
986 	snd_iprintf(buffer, "card: %d\n", compr->card->number);
987 	snd_iprintf(buffer, "device: %d\n", compr->device);
988 	snd_iprintf(buffer, "stream: %s\n",
989 			compr->direction == SND_COMPRESS_PLAYBACK
990 				? "PLAYBACK" : "CAPTURE");
991 	snd_iprintf(buffer, "id: %s\n", compr->id);
992 }
993 
994 static int snd_compress_proc_init(struct snd_compr *compr)
995 {
996 	struct snd_info_entry *entry;
997 	char name[16];
998 
999 	sprintf(name, "compr%i", compr->device);
1000 	entry = snd_info_create_card_entry(compr->card, name,
1001 					   compr->card->proc_root);
1002 	if (!entry)
1003 		return -ENOMEM;
1004 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
1005 	if (snd_info_register(entry) < 0) {
1006 		snd_info_free_entry(entry);
1007 		return -ENOMEM;
1008 	}
1009 	compr->proc_root = entry;
1010 
1011 	entry = snd_info_create_card_entry(compr->card, "info",
1012 					   compr->proc_root);
1013 	if (entry) {
1014 		snd_info_set_text_ops(entry, compr,
1015 				      snd_compress_proc_info_read);
1016 		if (snd_info_register(entry) < 0) {
1017 			snd_info_free_entry(entry);
1018 			entry = NULL;
1019 		}
1020 	}
1021 	compr->proc_info_entry = entry;
1022 
1023 	return 0;
1024 }
1025 
1026 static void snd_compress_proc_done(struct snd_compr *compr)
1027 {
1028 	snd_info_free_entry(compr->proc_info_entry);
1029 	compr->proc_info_entry = NULL;
1030 	snd_info_free_entry(compr->proc_root);
1031 	compr->proc_root = NULL;
1032 }
1033 
1034 static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
1035 {
1036 	strlcpy(compr->id, id, sizeof(compr->id));
1037 }
1038 #else
1039 static inline int snd_compress_proc_init(struct snd_compr *compr)
1040 {
1041 	return 0;
1042 }
1043 
1044 static inline void snd_compress_proc_done(struct snd_compr *compr)
1045 {
1046 }
1047 
1048 static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
1049 {
1050 }
1051 #endif
1052 
1053 static int snd_compress_dev_free(struct snd_device *device)
1054 {
1055 	struct snd_compr *compr;
1056 
1057 	compr = device->device_data;
1058 	snd_compress_proc_done(compr);
1059 	put_device(&compr->dev);
1060 	return 0;
1061 }
1062 
1063 /*
1064  * snd_compress_new: create new compress device
1065  * @card: sound card pointer
1066  * @device: device number
1067  * @dirn: device direction, should be of type enum snd_compr_direction
1068  * @compr: compress device pointer
1069  */
1070 int snd_compress_new(struct snd_card *card, int device,
1071 			int dirn, const char *id, struct snd_compr *compr)
1072 {
1073 	static struct snd_device_ops ops = {
1074 		.dev_free = snd_compress_dev_free,
1075 		.dev_register = snd_compress_dev_register,
1076 		.dev_disconnect = snd_compress_dev_disconnect,
1077 	};
1078 	int ret;
1079 
1080 	compr->card = card;
1081 	compr->device = device;
1082 	compr->direction = dirn;
1083 
1084 	snd_compress_set_id(compr, id);
1085 
1086 	snd_device_initialize(&compr->dev, card);
1087 	dev_set_name(&compr->dev, "comprC%iD%i", card->number, device);
1088 
1089 	ret = snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
1090 	if (ret == 0)
1091 		snd_compress_proc_init(compr);
1092 
1093 	return ret;
1094 }
1095 EXPORT_SYMBOL_GPL(snd_compress_new);
1096 
1097 static int snd_compress_add_device(struct snd_compr *device)
1098 {
1099 	int ret;
1100 
1101 	if (!device->card)
1102 		return -EINVAL;
1103 
1104 	/* register the card */
1105 	ret = snd_card_register(device->card);
1106 	if (ret)
1107 		goto out;
1108 	return 0;
1109 
1110 out:
1111 	pr_err("failed with %d\n", ret);
1112 	return ret;
1113 
1114 }
1115 
1116 static int snd_compress_remove_device(struct snd_compr *device)
1117 {
1118 	return snd_card_free(device->card);
1119 }
1120 
1121 /**
1122  * snd_compress_register - register compressed device
1123  *
1124  * @device: compressed device to register
1125  */
1126 int snd_compress_register(struct snd_compr *device)
1127 {
1128 	int retval;
1129 
1130 	if (device->name == NULL || device->ops == NULL)
1131 		return -EINVAL;
1132 
1133 	pr_debug("Registering compressed device %s\n", device->name);
1134 	if (snd_BUG_ON(!device->ops->open))
1135 		return -EINVAL;
1136 	if (snd_BUG_ON(!device->ops->free))
1137 		return -EINVAL;
1138 	if (snd_BUG_ON(!device->ops->set_params))
1139 		return -EINVAL;
1140 	if (snd_BUG_ON(!device->ops->trigger))
1141 		return -EINVAL;
1142 
1143 	mutex_init(&device->lock);
1144 
1145 	/* register a compressed card */
1146 	mutex_lock(&device_mutex);
1147 	retval = snd_compress_add_device(device);
1148 	mutex_unlock(&device_mutex);
1149 	return retval;
1150 }
1151 EXPORT_SYMBOL_GPL(snd_compress_register);
1152 
1153 int snd_compress_deregister(struct snd_compr *device)
1154 {
1155 	pr_debug("Removing compressed device %s\n", device->name);
1156 	mutex_lock(&device_mutex);
1157 	snd_compress_remove_device(device);
1158 	mutex_unlock(&device_mutex);
1159 	return 0;
1160 }
1161 EXPORT_SYMBOL_GPL(snd_compress_deregister);
1162 
1163 static int __init snd_compress_init(void)
1164 {
1165 	return 0;
1166 }
1167 
1168 static void __exit snd_compress_exit(void)
1169 {
1170 }
1171 
1172 module_init(snd_compress_init);
1173 module_exit(snd_compress_exit);
1174 
1175 MODULE_DESCRIPTION("ALSA Compressed offload framework");
1176 MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
1177 MODULE_LICENSE("GPL v2");
1178