xref: /openbmc/linux/sound/core/compress_offload.c (revision ccb01374)
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 	if (!data->stream.runtime->dma_buffer_p)
175 		kfree(data->stream.runtime->buffer);
176 	kfree(data->stream.runtime);
177 	kfree(data);
178 	return 0;
179 }
180 
181 static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
182 		struct snd_compr_tstamp *tstamp)
183 {
184 	if (!stream->ops->pointer)
185 		return -ENOTSUPP;
186 	stream->ops->pointer(stream, tstamp);
187 	pr_debug("dsp consumed till %d total %d bytes\n",
188 		tstamp->byte_offset, tstamp->copied_total);
189 	if (stream->direction == SND_COMPRESS_PLAYBACK)
190 		stream->runtime->total_bytes_transferred = tstamp->copied_total;
191 	else
192 		stream->runtime->total_bytes_available = tstamp->copied_total;
193 	return 0;
194 }
195 
196 static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
197 		struct snd_compr_avail *avail)
198 {
199 	memset(avail, 0, sizeof(*avail));
200 	snd_compr_update_tstamp(stream, &avail->tstamp);
201 	/* Still need to return avail even if tstamp can't be filled in */
202 
203 	if (stream->runtime->total_bytes_available == 0 &&
204 			stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
205 			stream->direction == SND_COMPRESS_PLAYBACK) {
206 		pr_debug("detected init and someone forgot to do a write\n");
207 		return stream->runtime->buffer_size;
208 	}
209 	pr_debug("app wrote %lld, DSP consumed %lld\n",
210 			stream->runtime->total_bytes_available,
211 			stream->runtime->total_bytes_transferred);
212 	if (stream->runtime->total_bytes_available ==
213 				stream->runtime->total_bytes_transferred) {
214 		if (stream->direction == SND_COMPRESS_PLAYBACK) {
215 			pr_debug("both pointers are same, returning full avail\n");
216 			return stream->runtime->buffer_size;
217 		} else {
218 			pr_debug("both pointers are same, returning no avail\n");
219 			return 0;
220 		}
221 	}
222 
223 	avail->avail = stream->runtime->total_bytes_available -
224 			stream->runtime->total_bytes_transferred;
225 	if (stream->direction == SND_COMPRESS_PLAYBACK)
226 		avail->avail = stream->runtime->buffer_size - avail->avail;
227 
228 	pr_debug("ret avail as %lld\n", avail->avail);
229 	return avail->avail;
230 }
231 
232 static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
233 {
234 	struct snd_compr_avail avail;
235 
236 	return snd_compr_calc_avail(stream, &avail);
237 }
238 
239 static int
240 snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
241 {
242 	struct snd_compr_avail ioctl_avail;
243 	size_t avail;
244 
245 	avail = snd_compr_calc_avail(stream, &ioctl_avail);
246 	ioctl_avail.avail = avail;
247 
248 	switch (stream->runtime->state) {
249 	case SNDRV_PCM_STATE_OPEN:
250 		return -EBADFD;
251 	case SNDRV_PCM_STATE_XRUN:
252 		return -EPIPE;
253 	default:
254 		break;
255 	}
256 
257 	if (copy_to_user((__u64 __user *)arg,
258 				&ioctl_avail, sizeof(ioctl_avail)))
259 		return -EFAULT;
260 	return 0;
261 }
262 
263 static int snd_compr_write_data(struct snd_compr_stream *stream,
264 	       const char __user *buf, size_t count)
265 {
266 	void *dstn;
267 	size_t copy;
268 	struct snd_compr_runtime *runtime = stream->runtime;
269 	/* 64-bit Modulus */
270 	u64 app_pointer = div64_u64(runtime->total_bytes_available,
271 				    runtime->buffer_size);
272 	app_pointer = runtime->total_bytes_available -
273 		      (app_pointer * runtime->buffer_size);
274 
275 	dstn = runtime->buffer + app_pointer;
276 	pr_debug("copying %ld at %lld\n",
277 			(unsigned long)count, app_pointer);
278 	if (count < runtime->buffer_size - app_pointer) {
279 		if (copy_from_user(dstn, buf, count))
280 			return -EFAULT;
281 	} else {
282 		copy = runtime->buffer_size - app_pointer;
283 		if (copy_from_user(dstn, buf, copy))
284 			return -EFAULT;
285 		if (copy_from_user(runtime->buffer, buf + copy, count - copy))
286 			return -EFAULT;
287 	}
288 	/* if DSP cares, let it know data has been written */
289 	if (stream->ops->ack)
290 		stream->ops->ack(stream, count);
291 	return count;
292 }
293 
294 static ssize_t snd_compr_write(struct file *f, const char __user *buf,
295 		size_t count, loff_t *offset)
296 {
297 	struct snd_compr_file *data = f->private_data;
298 	struct snd_compr_stream *stream;
299 	size_t avail;
300 	int retval;
301 
302 	if (snd_BUG_ON(!data))
303 		return -EFAULT;
304 
305 	stream = &data->stream;
306 	mutex_lock(&stream->device->lock);
307 	/* write is allowed when stream is running or has been steup */
308 	switch (stream->runtime->state) {
309 	case SNDRV_PCM_STATE_SETUP:
310 	case SNDRV_PCM_STATE_PREPARED:
311 	case SNDRV_PCM_STATE_RUNNING:
312 		break;
313 	default:
314 		mutex_unlock(&stream->device->lock);
315 		return -EBADFD;
316 	}
317 
318 	avail = snd_compr_get_avail(stream);
319 	pr_debug("avail returned %ld\n", (unsigned long)avail);
320 	/* calculate how much we can write to buffer */
321 	if (avail > count)
322 		avail = count;
323 
324 	if (stream->ops->copy) {
325 		char __user* cbuf = (char __user*)buf;
326 		retval = stream->ops->copy(stream, cbuf, avail);
327 	} else {
328 		retval = snd_compr_write_data(stream, buf, avail);
329 	}
330 	if (retval > 0)
331 		stream->runtime->total_bytes_available += retval;
332 
333 	/* while initiating the stream, write should be called before START
334 	 * call, so in setup move state */
335 	if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
336 		stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
337 		pr_debug("stream prepared, Houston we are good to go\n");
338 	}
339 
340 	mutex_unlock(&stream->device->lock);
341 	return retval;
342 }
343 
344 
345 static ssize_t snd_compr_read(struct file *f, char __user *buf,
346 		size_t count, loff_t *offset)
347 {
348 	struct snd_compr_file *data = f->private_data;
349 	struct snd_compr_stream *stream;
350 	size_t avail;
351 	int retval;
352 
353 	if (snd_BUG_ON(!data))
354 		return -EFAULT;
355 
356 	stream = &data->stream;
357 	mutex_lock(&stream->device->lock);
358 
359 	/* read is allowed when stream is running, paused, draining and setup
360 	 * (yes setup is state which we transition to after stop, so if user
361 	 * wants to read data after stop we allow that)
362 	 */
363 	switch (stream->runtime->state) {
364 	case SNDRV_PCM_STATE_OPEN:
365 	case SNDRV_PCM_STATE_PREPARED:
366 	case SNDRV_PCM_STATE_SUSPENDED:
367 	case SNDRV_PCM_STATE_DISCONNECTED:
368 		retval = -EBADFD;
369 		goto out;
370 	case SNDRV_PCM_STATE_XRUN:
371 		retval = -EPIPE;
372 		goto out;
373 	}
374 
375 	avail = snd_compr_get_avail(stream);
376 	pr_debug("avail returned %ld\n", (unsigned long)avail);
377 	/* calculate how much we can read from buffer */
378 	if (avail > count)
379 		avail = count;
380 
381 	if (stream->ops->copy) {
382 		retval = stream->ops->copy(stream, buf, avail);
383 	} else {
384 		retval = -ENXIO;
385 		goto out;
386 	}
387 	if (retval > 0)
388 		stream->runtime->total_bytes_transferred += retval;
389 
390 out:
391 	mutex_unlock(&stream->device->lock);
392 	return retval;
393 }
394 
395 static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
396 {
397 	return -ENXIO;
398 }
399 
400 static __poll_t snd_compr_get_poll(struct snd_compr_stream *stream)
401 {
402 	if (stream->direction == SND_COMPRESS_PLAYBACK)
403 		return EPOLLOUT | EPOLLWRNORM;
404 	else
405 		return EPOLLIN | EPOLLRDNORM;
406 }
407 
408 static __poll_t snd_compr_poll(struct file *f, poll_table *wait)
409 {
410 	struct snd_compr_file *data = f->private_data;
411 	struct snd_compr_stream *stream;
412 	size_t avail;
413 	__poll_t retval = 0;
414 
415 	if (snd_BUG_ON(!data))
416 		return EPOLLERR;
417 
418 	stream = &data->stream;
419 
420 	mutex_lock(&stream->device->lock);
421 
422 	switch (stream->runtime->state) {
423 	case SNDRV_PCM_STATE_OPEN:
424 	case SNDRV_PCM_STATE_XRUN:
425 		retval = snd_compr_get_poll(stream) | EPOLLERR;
426 		goto out;
427 	default:
428 		break;
429 	}
430 
431 	poll_wait(f, &stream->runtime->sleep, wait);
432 
433 	avail = snd_compr_get_avail(stream);
434 	pr_debug("avail is %ld\n", (unsigned long)avail);
435 	/* check if we have at least one fragment to fill */
436 	switch (stream->runtime->state) {
437 	case SNDRV_PCM_STATE_DRAINING:
438 		/* stream has been woken up after drain is complete
439 		 * draining done so set stream state to stopped
440 		 */
441 		retval = snd_compr_get_poll(stream);
442 		stream->runtime->state = SNDRV_PCM_STATE_SETUP;
443 		break;
444 	case SNDRV_PCM_STATE_RUNNING:
445 	case SNDRV_PCM_STATE_PREPARED:
446 	case SNDRV_PCM_STATE_PAUSED:
447 		if (avail >= stream->runtime->fragment_size)
448 			retval = snd_compr_get_poll(stream);
449 		break;
450 	default:
451 		retval = snd_compr_get_poll(stream) | EPOLLERR;
452 		break;
453 	}
454 out:
455 	mutex_unlock(&stream->device->lock);
456 	return retval;
457 }
458 
459 static int
460 snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
461 {
462 	int retval;
463 	struct snd_compr_caps caps;
464 
465 	if (!stream->ops->get_caps)
466 		return -ENXIO;
467 
468 	memset(&caps, 0, sizeof(caps));
469 	retval = stream->ops->get_caps(stream, &caps);
470 	if (retval)
471 		goto out;
472 	if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
473 		retval = -EFAULT;
474 out:
475 	return retval;
476 }
477 
478 #ifndef COMPR_CODEC_CAPS_OVERFLOW
479 static int
480 snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
481 {
482 	int retval;
483 	struct snd_compr_codec_caps *caps;
484 
485 	if (!stream->ops->get_codec_caps)
486 		return -ENXIO;
487 
488 	caps = kzalloc(sizeof(*caps), GFP_KERNEL);
489 	if (!caps)
490 		return -ENOMEM;
491 
492 	retval = stream->ops->get_codec_caps(stream, caps);
493 	if (retval)
494 		goto out;
495 	if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
496 		retval = -EFAULT;
497 
498 out:
499 	kfree(caps);
500 	return retval;
501 }
502 #endif /* !COMPR_CODEC_CAPS_OVERFLOW */
503 
504 /* revisit this with snd_pcm_preallocate_xxx */
505 static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
506 		struct snd_compr_params *params)
507 {
508 	unsigned int buffer_size;
509 	void *buffer = NULL;
510 
511 	buffer_size = params->buffer.fragment_size * params->buffer.fragments;
512 	if (stream->ops->copy) {
513 		buffer = NULL;
514 		/* if copy is defined the driver will be required to copy
515 		 * the data from core
516 		 */
517 	} else {
518 		if (stream->runtime->dma_buffer_p) {
519 
520 			if (buffer_size > stream->runtime->dma_buffer_p->bytes)
521 				dev_err(&stream->device->dev,
522 						"Not enough DMA buffer");
523 			else
524 				buffer = stream->runtime->dma_buffer_p->area;
525 
526 		} else {
527 			buffer = kmalloc(buffer_size, GFP_KERNEL);
528 		}
529 
530 		if (!buffer)
531 			return -ENOMEM;
532 	}
533 	stream->runtime->fragment_size = params->buffer.fragment_size;
534 	stream->runtime->fragments = params->buffer.fragments;
535 	stream->runtime->buffer = buffer;
536 	stream->runtime->buffer_size = buffer_size;
537 	return 0;
538 }
539 
540 static int snd_compress_check_input(struct snd_compr_params *params)
541 {
542 	/* first let's check the buffer parameter's */
543 	if (params->buffer.fragment_size == 0 ||
544 	    params->buffer.fragments > INT_MAX / params->buffer.fragment_size)
545 		return -EINVAL;
546 
547 	/* now codec parameters */
548 	if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
549 		return -EINVAL;
550 
551 	if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
552 		return -EINVAL;
553 
554 	return 0;
555 }
556 
557 static int
558 snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
559 {
560 	struct snd_compr_params *params;
561 	int retval;
562 
563 	if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
564 		/*
565 		 * we should allow parameter change only when stream has been
566 		 * opened not in other cases
567 		 */
568 		params = memdup_user((void __user *)arg, sizeof(*params));
569 		if (IS_ERR(params))
570 			return PTR_ERR(params);
571 
572 		retval = snd_compress_check_input(params);
573 		if (retval)
574 			goto out;
575 
576 		retval = snd_compr_allocate_buffer(stream, params);
577 		if (retval) {
578 			retval = -ENOMEM;
579 			goto out;
580 		}
581 
582 		retval = stream->ops->set_params(stream, params);
583 		if (retval)
584 			goto out;
585 
586 		stream->metadata_set = false;
587 		stream->next_track = false;
588 
589 		if (stream->direction == SND_COMPRESS_PLAYBACK)
590 			stream->runtime->state = SNDRV_PCM_STATE_SETUP;
591 		else
592 			stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
593 	} else {
594 		return -EPERM;
595 	}
596 out:
597 	kfree(params);
598 	return retval;
599 }
600 
601 static int
602 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
603 {
604 	struct snd_codec *params;
605 	int retval;
606 
607 	if (!stream->ops->get_params)
608 		return -EBADFD;
609 
610 	params = kzalloc(sizeof(*params), GFP_KERNEL);
611 	if (!params)
612 		return -ENOMEM;
613 	retval = stream->ops->get_params(stream, params);
614 	if (retval)
615 		goto out;
616 	if (copy_to_user((char __user *)arg, params, sizeof(*params)))
617 		retval = -EFAULT;
618 
619 out:
620 	kfree(params);
621 	return retval;
622 }
623 
624 static int
625 snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
626 {
627 	struct snd_compr_metadata metadata;
628 	int retval;
629 
630 	if (!stream->ops->get_metadata)
631 		return -ENXIO;
632 
633 	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
634 		return -EFAULT;
635 
636 	retval = stream->ops->get_metadata(stream, &metadata);
637 	if (retval != 0)
638 		return retval;
639 
640 	if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
641 		return -EFAULT;
642 
643 	return 0;
644 }
645 
646 static int
647 snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
648 {
649 	struct snd_compr_metadata metadata;
650 	int retval;
651 
652 	if (!stream->ops->set_metadata)
653 		return -ENXIO;
654 	/*
655 	* we should allow parameter change only when stream has been
656 	* opened not in other cases
657 	*/
658 	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
659 		return -EFAULT;
660 
661 	retval = stream->ops->set_metadata(stream, &metadata);
662 	stream->metadata_set = true;
663 
664 	return retval;
665 }
666 
667 static inline int
668 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
669 {
670 	struct snd_compr_tstamp tstamp = {0};
671 	int ret;
672 
673 	ret = snd_compr_update_tstamp(stream, &tstamp);
674 	if (ret == 0)
675 		ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
676 			&tstamp, sizeof(tstamp)) ? -EFAULT : 0;
677 	return ret;
678 }
679 
680 static int snd_compr_pause(struct snd_compr_stream *stream)
681 {
682 	int retval;
683 
684 	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
685 		return -EPERM;
686 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
687 	if (!retval)
688 		stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
689 	return retval;
690 }
691 
692 static int snd_compr_resume(struct snd_compr_stream *stream)
693 {
694 	int retval;
695 
696 	if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
697 		return -EPERM;
698 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
699 	if (!retval)
700 		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
701 	return retval;
702 }
703 
704 static int snd_compr_start(struct snd_compr_stream *stream)
705 {
706 	int retval;
707 
708 	if (stream->runtime->state != SNDRV_PCM_STATE_PREPARED)
709 		return -EPERM;
710 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
711 	if (!retval)
712 		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
713 	return retval;
714 }
715 
716 static int snd_compr_stop(struct snd_compr_stream *stream)
717 {
718 	int retval;
719 
720 	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
721 			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
722 		return -EPERM;
723 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
724 	if (!retval) {
725 		snd_compr_drain_notify(stream);
726 		stream->runtime->total_bytes_available = 0;
727 		stream->runtime->total_bytes_transferred = 0;
728 	}
729 	return retval;
730 }
731 
732 static void error_delayed_work(struct work_struct *work)
733 {
734 	struct snd_compr_stream *stream;
735 
736 	stream = container_of(work, struct snd_compr_stream, error_work.work);
737 
738 	mutex_lock(&stream->device->lock);
739 
740 	stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
741 	wake_up(&stream->runtime->sleep);
742 
743 	mutex_unlock(&stream->device->lock);
744 }
745 
746 /*
747  * snd_compr_stop_error: Report a fatal error on a stream
748  * @stream: pointer to stream
749  * @state: state to transition the stream to
750  *
751  * Stop the stream and set its state.
752  *
753  * Should be called with compressed device lock held.
754  */
755 int snd_compr_stop_error(struct snd_compr_stream *stream,
756 			 snd_pcm_state_t state)
757 {
758 	if (stream->runtime->state == state)
759 		return 0;
760 
761 	stream->runtime->state = state;
762 
763 	pr_debug("Changing state to: %d\n", state);
764 
765 	queue_delayed_work(system_power_efficient_wq, &stream->error_work, 0);
766 
767 	return 0;
768 }
769 EXPORT_SYMBOL_GPL(snd_compr_stop_error);
770 
771 static int snd_compress_wait_for_drain(struct snd_compr_stream *stream)
772 {
773 	int ret;
774 
775 	/*
776 	 * We are called with lock held. So drop the lock while we wait for
777 	 * drain complete notification from the driver
778 	 *
779 	 * It is expected that driver will notify the drain completion and then
780 	 * stream will be moved to SETUP state, even if draining resulted in an
781 	 * error. We can trigger next track after this.
782 	 */
783 	stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
784 	mutex_unlock(&stream->device->lock);
785 
786 	/* we wait for drain to complete here, drain can return when
787 	 * interruption occurred, wait returned error or success.
788 	 * For the first two cases we don't do anything different here and
789 	 * return after waking up
790 	 */
791 
792 	ret = wait_event_interruptible(stream->runtime->sleep,
793 			(stream->runtime->state != SNDRV_PCM_STATE_DRAINING));
794 	if (ret == -ERESTARTSYS)
795 		pr_debug("wait aborted by a signal\n");
796 	else if (ret)
797 		pr_debug("wait for drain failed with %d\n", ret);
798 
799 
800 	wake_up(&stream->runtime->sleep);
801 	mutex_lock(&stream->device->lock);
802 
803 	return ret;
804 }
805 
806 static int snd_compr_drain(struct snd_compr_stream *stream)
807 {
808 	int retval;
809 
810 	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
811 			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
812 		return -EPERM;
813 
814 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
815 	if (retval) {
816 		pr_debug("SND_COMPR_TRIGGER_DRAIN failed %d\n", retval);
817 		wake_up(&stream->runtime->sleep);
818 		return retval;
819 	}
820 
821 	return snd_compress_wait_for_drain(stream);
822 }
823 
824 static int snd_compr_next_track(struct snd_compr_stream *stream)
825 {
826 	int retval;
827 
828 	/* only a running stream can transition to next track */
829 	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
830 		return -EPERM;
831 
832 	/* you can signal next track if this is intended to be a gapless stream
833 	 * and current track metadata is set
834 	 */
835 	if (stream->metadata_set == false)
836 		return -EPERM;
837 
838 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
839 	if (retval != 0)
840 		return retval;
841 	stream->metadata_set = false;
842 	stream->next_track = true;
843 	return 0;
844 }
845 
846 static int snd_compr_partial_drain(struct snd_compr_stream *stream)
847 {
848 	int retval;
849 	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
850 			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
851 		return -EPERM;
852 	/* stream can be drained only when next track has been signalled */
853 	if (stream->next_track == false)
854 		return -EPERM;
855 
856 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
857 	if (retval) {
858 		pr_debug("Partial drain returned failure\n");
859 		wake_up(&stream->runtime->sleep);
860 		return retval;
861 	}
862 
863 	stream->next_track = false;
864 	return snd_compress_wait_for_drain(stream);
865 }
866 
867 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
868 {
869 	struct snd_compr_file *data = f->private_data;
870 	struct snd_compr_stream *stream;
871 	int retval = -ENOTTY;
872 
873 	if (snd_BUG_ON(!data))
874 		return -EFAULT;
875 
876 	stream = &data->stream;
877 
878 	mutex_lock(&stream->device->lock);
879 	switch (_IOC_NR(cmd)) {
880 	case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
881 		retval = put_user(SNDRV_COMPRESS_VERSION,
882 				(int __user *)arg) ? -EFAULT : 0;
883 		break;
884 	case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
885 		retval = snd_compr_get_caps(stream, arg);
886 		break;
887 #ifndef COMPR_CODEC_CAPS_OVERFLOW
888 	case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
889 		retval = snd_compr_get_codec_caps(stream, arg);
890 		break;
891 #endif
892 	case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
893 		retval = snd_compr_set_params(stream, arg);
894 		break;
895 	case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
896 		retval = snd_compr_get_params(stream, arg);
897 		break;
898 	case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
899 		retval = snd_compr_set_metadata(stream, arg);
900 		break;
901 	case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
902 		retval = snd_compr_get_metadata(stream, arg);
903 		break;
904 	case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
905 		retval = snd_compr_tstamp(stream, arg);
906 		break;
907 	case _IOC_NR(SNDRV_COMPRESS_AVAIL):
908 		retval = snd_compr_ioctl_avail(stream, arg);
909 		break;
910 	case _IOC_NR(SNDRV_COMPRESS_PAUSE):
911 		retval = snd_compr_pause(stream);
912 		break;
913 	case _IOC_NR(SNDRV_COMPRESS_RESUME):
914 		retval = snd_compr_resume(stream);
915 		break;
916 	case _IOC_NR(SNDRV_COMPRESS_START):
917 		retval = snd_compr_start(stream);
918 		break;
919 	case _IOC_NR(SNDRV_COMPRESS_STOP):
920 		retval = snd_compr_stop(stream);
921 		break;
922 	case _IOC_NR(SNDRV_COMPRESS_DRAIN):
923 		retval = snd_compr_drain(stream);
924 		break;
925 	case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
926 		retval = snd_compr_partial_drain(stream);
927 		break;
928 	case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
929 		retval = snd_compr_next_track(stream);
930 		break;
931 
932 	}
933 	mutex_unlock(&stream->device->lock);
934 	return retval;
935 }
936 
937 /* support of 32bit userspace on 64bit platforms */
938 #ifdef CONFIG_COMPAT
939 static long snd_compr_ioctl_compat(struct file *file, unsigned int cmd,
940 						unsigned long arg)
941 {
942 	return snd_compr_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
943 }
944 #endif
945 
946 static const struct file_operations snd_compr_file_ops = {
947 		.owner =	THIS_MODULE,
948 		.open =		snd_compr_open,
949 		.release =	snd_compr_free,
950 		.write =	snd_compr_write,
951 		.read =		snd_compr_read,
952 		.unlocked_ioctl = snd_compr_ioctl,
953 #ifdef CONFIG_COMPAT
954 		.compat_ioctl = snd_compr_ioctl_compat,
955 #endif
956 		.mmap =		snd_compr_mmap,
957 		.poll =		snd_compr_poll,
958 };
959 
960 static int snd_compress_dev_register(struct snd_device *device)
961 {
962 	int ret = -EINVAL;
963 	struct snd_compr *compr;
964 
965 	if (snd_BUG_ON(!device || !device->device_data))
966 		return -EBADFD;
967 	compr = device->device_data;
968 
969 	pr_debug("reg device %s, direction %d\n", compr->name,
970 			compr->direction);
971 	/* register compressed device */
972 	ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS,
973 				  compr->card, compr->device,
974 				  &snd_compr_file_ops, compr, &compr->dev);
975 	if (ret < 0) {
976 		pr_err("snd_register_device failed %d\n", ret);
977 		return ret;
978 	}
979 	return ret;
980 
981 }
982 
983 static int snd_compress_dev_disconnect(struct snd_device *device)
984 {
985 	struct snd_compr *compr;
986 
987 	compr = device->device_data;
988 	snd_unregister_device(&compr->dev);
989 	return 0;
990 }
991 
992 #ifdef CONFIG_SND_VERBOSE_PROCFS
993 static void snd_compress_proc_info_read(struct snd_info_entry *entry,
994 					struct snd_info_buffer *buffer)
995 {
996 	struct snd_compr *compr = (struct snd_compr *)entry->private_data;
997 
998 	snd_iprintf(buffer, "card: %d\n", compr->card->number);
999 	snd_iprintf(buffer, "device: %d\n", compr->device);
1000 	snd_iprintf(buffer, "stream: %s\n",
1001 			compr->direction == SND_COMPRESS_PLAYBACK
1002 				? "PLAYBACK" : "CAPTURE");
1003 	snd_iprintf(buffer, "id: %s\n", compr->id);
1004 }
1005 
1006 static int snd_compress_proc_init(struct snd_compr *compr)
1007 {
1008 	struct snd_info_entry *entry;
1009 	char name[16];
1010 
1011 	sprintf(name, "compr%i", compr->device);
1012 	entry = snd_info_create_card_entry(compr->card, name,
1013 					   compr->card->proc_root);
1014 	if (!entry)
1015 		return -ENOMEM;
1016 	entry->mode = S_IFDIR | 0555;
1017 	if (snd_info_register(entry) < 0) {
1018 		snd_info_free_entry(entry);
1019 		return -ENOMEM;
1020 	}
1021 	compr->proc_root = entry;
1022 
1023 	entry = snd_info_create_card_entry(compr->card, "info",
1024 					   compr->proc_root);
1025 	if (entry) {
1026 		snd_info_set_text_ops(entry, compr,
1027 				      snd_compress_proc_info_read);
1028 		if (snd_info_register(entry) < 0) {
1029 			snd_info_free_entry(entry);
1030 			entry = NULL;
1031 		}
1032 	}
1033 	compr->proc_info_entry = entry;
1034 
1035 	return 0;
1036 }
1037 
1038 static void snd_compress_proc_done(struct snd_compr *compr)
1039 {
1040 	snd_info_free_entry(compr->proc_info_entry);
1041 	compr->proc_info_entry = NULL;
1042 	snd_info_free_entry(compr->proc_root);
1043 	compr->proc_root = NULL;
1044 }
1045 
1046 static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
1047 {
1048 	strlcpy(compr->id, id, sizeof(compr->id));
1049 }
1050 #else
1051 static inline int snd_compress_proc_init(struct snd_compr *compr)
1052 {
1053 	return 0;
1054 }
1055 
1056 static inline void snd_compress_proc_done(struct snd_compr *compr)
1057 {
1058 }
1059 
1060 static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
1061 {
1062 }
1063 #endif
1064 
1065 static int snd_compress_dev_free(struct snd_device *device)
1066 {
1067 	struct snd_compr *compr;
1068 
1069 	compr = device->device_data;
1070 	snd_compress_proc_done(compr);
1071 	put_device(&compr->dev);
1072 	return 0;
1073 }
1074 
1075 /*
1076  * snd_compress_new: create new compress device
1077  * @card: sound card pointer
1078  * @device: device number
1079  * @dirn: device direction, should be of type enum snd_compr_direction
1080  * @compr: compress device pointer
1081  */
1082 int snd_compress_new(struct snd_card *card, int device,
1083 			int dirn, const char *id, struct snd_compr *compr)
1084 {
1085 	static struct snd_device_ops ops = {
1086 		.dev_free = snd_compress_dev_free,
1087 		.dev_register = snd_compress_dev_register,
1088 		.dev_disconnect = snd_compress_dev_disconnect,
1089 	};
1090 	int ret;
1091 
1092 	compr->card = card;
1093 	compr->device = device;
1094 	compr->direction = dirn;
1095 
1096 	snd_compress_set_id(compr, id);
1097 
1098 	snd_device_initialize(&compr->dev, card);
1099 	dev_set_name(&compr->dev, "comprC%iD%i", card->number, device);
1100 
1101 	ret = snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
1102 	if (ret == 0)
1103 		snd_compress_proc_init(compr);
1104 
1105 	return ret;
1106 }
1107 EXPORT_SYMBOL_GPL(snd_compress_new);
1108 
1109 static int snd_compress_add_device(struct snd_compr *device)
1110 {
1111 	int ret;
1112 
1113 	if (!device->card)
1114 		return -EINVAL;
1115 
1116 	/* register the card */
1117 	ret = snd_card_register(device->card);
1118 	if (ret)
1119 		goto out;
1120 	return 0;
1121 
1122 out:
1123 	pr_err("failed with %d\n", ret);
1124 	return ret;
1125 
1126 }
1127 
1128 static int snd_compress_remove_device(struct snd_compr *device)
1129 {
1130 	return snd_card_free(device->card);
1131 }
1132 
1133 /**
1134  * snd_compress_register - register compressed device
1135  *
1136  * @device: compressed device to register
1137  */
1138 int snd_compress_register(struct snd_compr *device)
1139 {
1140 	int retval;
1141 
1142 	if (device->name == NULL || device->ops == NULL)
1143 		return -EINVAL;
1144 
1145 	pr_debug("Registering compressed device %s\n", device->name);
1146 	if (snd_BUG_ON(!device->ops->open))
1147 		return -EINVAL;
1148 	if (snd_BUG_ON(!device->ops->free))
1149 		return -EINVAL;
1150 	if (snd_BUG_ON(!device->ops->set_params))
1151 		return -EINVAL;
1152 	if (snd_BUG_ON(!device->ops->trigger))
1153 		return -EINVAL;
1154 
1155 	mutex_init(&device->lock);
1156 
1157 	/* register a compressed card */
1158 	mutex_lock(&device_mutex);
1159 	retval = snd_compress_add_device(device);
1160 	mutex_unlock(&device_mutex);
1161 	return retval;
1162 }
1163 EXPORT_SYMBOL_GPL(snd_compress_register);
1164 
1165 int snd_compress_deregister(struct snd_compr *device)
1166 {
1167 	pr_debug("Removing compressed device %s\n", device->name);
1168 	mutex_lock(&device_mutex);
1169 	snd_compress_remove_device(device);
1170 	mutex_unlock(&device_mutex);
1171 	return 0;
1172 }
1173 EXPORT_SYMBOL_GPL(snd_compress_deregister);
1174 
1175 MODULE_DESCRIPTION("ALSA Compressed offload framework");
1176 MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
1177 MODULE_LICENSE("GPL v2");
1178