xref: /openbmc/linux/sound/core/compress_offload.c (revision fb574682)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  compress_core.c - compress offload core
4  *
5  *  Copyright (C) 2011 Intel Corporation
6  *  Authors:	Vinod Koul <vinod.koul@linux.intel.com>
7  *		Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
8  *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *
10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11  */
12 #define FORMAT(fmt) "%s: %d: " fmt, __func__, __LINE__
13 #define pr_fmt(fmt) KBUILD_MODNAME ": " FORMAT(fmt)
14 
15 #include <linux/file.h>
16 #include <linux/fs.h>
17 #include <linux/list.h>
18 #include <linux/math64.h>
19 #include <linux/mm.h>
20 #include <linux/mutex.h>
21 #include <linux/poll.h>
22 #include <linux/slab.h>
23 #include <linux/sched.h>
24 #include <linux/types.h>
25 #include <linux/uio.h>
26 #include <linux/uaccess.h>
27 #include <linux/module.h>
28 #include <linux/compat.h>
29 #include <sound/core.h>
30 #include <sound/initval.h>
31 #include <sound/info.h>
32 #include <sound/compress_params.h>
33 #include <sound/compress_offload.h>
34 #include <sound/compress_driver.h>
35 
36 /* struct snd_compr_codec_caps overflows the ioctl bit size for some
37  * architectures, so we need to disable the relevant ioctls.
38  */
39 #if _IOC_SIZEBITS < 14
40 #define COMPR_CODEC_CAPS_OVERFLOW
41 #endif
42 
43 /* TODO:
44  * - add substream support for multiple devices in case of
45  *	SND_DYNAMIC_MINORS is not used
46  * - Multiple node representation
47  *	driver should be able to register multiple nodes
48  */
49 
50 static DEFINE_MUTEX(device_mutex);
51 
52 struct snd_compr_file {
53 	unsigned long caps;
54 	struct snd_compr_stream stream;
55 };
56 
57 static void error_delayed_work(struct work_struct *work);
58 
59 /*
60  * a note on stream states used:
61  * we use following states in the compressed core
62  * SNDRV_PCM_STATE_OPEN: When stream has been opened.
63  * SNDRV_PCM_STATE_SETUP: When stream has been initialized. This is done by
64  *	calling SNDRV_COMPRESS_SET_PARAMS. Running streams will come to this
65  *	state at stop by calling SNDRV_COMPRESS_STOP, or at end of drain.
66  * SNDRV_PCM_STATE_PREPARED: When a stream has been written to (for
67  *	playback only). User after setting up stream writes the data buffer
68  *	before starting the stream.
69  * SNDRV_PCM_STATE_RUNNING: When stream has been started and is
70  *	decoding/encoding and rendering/capturing data.
71  * SNDRV_PCM_STATE_DRAINING: When stream is draining current data. This is done
72  *	by calling SNDRV_COMPRESS_DRAIN.
73  * SNDRV_PCM_STATE_PAUSED: When stream is paused. This is done by calling
74  *	SNDRV_COMPRESS_PAUSE. It can be stopped or resumed by calling
75  *	SNDRV_COMPRESS_STOP or SNDRV_COMPRESS_RESUME respectively.
76  */
77 static int snd_compr_open(struct inode *inode, struct file *f)
78 {
79 	struct snd_compr *compr;
80 	struct snd_compr_file *data;
81 	struct snd_compr_runtime *runtime;
82 	enum snd_compr_direction dirn;
83 	int maj = imajor(inode);
84 	int ret;
85 
86 	if ((f->f_flags & O_ACCMODE) == O_WRONLY)
87 		dirn = SND_COMPRESS_PLAYBACK;
88 	else if ((f->f_flags & O_ACCMODE) == O_RDONLY)
89 		dirn = SND_COMPRESS_CAPTURE;
90 	else
91 		return -EINVAL;
92 
93 	if (maj == snd_major)
94 		compr = snd_lookup_minor_data(iminor(inode),
95 					SNDRV_DEVICE_TYPE_COMPRESS);
96 	else
97 		return -EBADFD;
98 
99 	if (compr == NULL) {
100 		pr_err("no device data!!!\n");
101 		return -ENODEV;
102 	}
103 
104 	if (dirn != compr->direction) {
105 		pr_err("this device doesn't support this direction\n");
106 		snd_card_unref(compr->card);
107 		return -EINVAL;
108 	}
109 
110 	data = kzalloc(sizeof(*data), GFP_KERNEL);
111 	if (!data) {
112 		snd_card_unref(compr->card);
113 		return -ENOMEM;
114 	}
115 
116 	INIT_DELAYED_WORK(&data->stream.error_work, error_delayed_work);
117 
118 	data->stream.ops = compr->ops;
119 	data->stream.direction = dirn;
120 	data->stream.private_data = compr->private_data;
121 	data->stream.device = compr;
122 	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
123 	if (!runtime) {
124 		kfree(data);
125 		snd_card_unref(compr->card);
126 		return -ENOMEM;
127 	}
128 	runtime->state = SNDRV_PCM_STATE_OPEN;
129 	init_waitqueue_head(&runtime->sleep);
130 	data->stream.runtime = runtime;
131 	f->private_data = (void *)data;
132 	mutex_lock(&compr->lock);
133 	ret = compr->ops->open(&data->stream);
134 	mutex_unlock(&compr->lock);
135 	if (ret) {
136 		kfree(runtime);
137 		kfree(data);
138 	}
139 	snd_card_unref(compr->card);
140 	return ret;
141 }
142 
143 static int snd_compr_free(struct inode *inode, struct file *f)
144 {
145 	struct snd_compr_file *data = f->private_data;
146 	struct snd_compr_runtime *runtime = data->stream.runtime;
147 
148 	cancel_delayed_work_sync(&data->stream.error_work);
149 
150 	switch (runtime->state) {
151 	case SNDRV_PCM_STATE_RUNNING:
152 	case SNDRV_PCM_STATE_DRAINING:
153 	case SNDRV_PCM_STATE_PAUSED:
154 		data->stream.ops->trigger(&data->stream, SNDRV_PCM_TRIGGER_STOP);
155 		break;
156 	default:
157 		break;
158 	}
159 
160 	data->stream.ops->free(&data->stream);
161 	if (!data->stream.runtime->dma_buffer_p)
162 		kfree(data->stream.runtime->buffer);
163 	kfree(data->stream.runtime);
164 	kfree(data);
165 	return 0;
166 }
167 
168 static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
169 		struct snd_compr_tstamp *tstamp)
170 {
171 	if (!stream->ops->pointer)
172 		return -ENOTSUPP;
173 	stream->ops->pointer(stream, tstamp);
174 	pr_debug("dsp consumed till %d total %d bytes\n",
175 		tstamp->byte_offset, tstamp->copied_total);
176 	if (stream->direction == SND_COMPRESS_PLAYBACK)
177 		stream->runtime->total_bytes_transferred = tstamp->copied_total;
178 	else
179 		stream->runtime->total_bytes_available = tstamp->copied_total;
180 	return 0;
181 }
182 
183 static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
184 		struct snd_compr_avail *avail)
185 {
186 	memset(avail, 0, sizeof(*avail));
187 	snd_compr_update_tstamp(stream, &avail->tstamp);
188 	/* Still need to return avail even if tstamp can't be filled in */
189 
190 	if (stream->runtime->total_bytes_available == 0 &&
191 			stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
192 			stream->direction == SND_COMPRESS_PLAYBACK) {
193 		pr_debug("detected init and someone forgot to do a write\n");
194 		return stream->runtime->buffer_size;
195 	}
196 	pr_debug("app wrote %lld, DSP consumed %lld\n",
197 			stream->runtime->total_bytes_available,
198 			stream->runtime->total_bytes_transferred);
199 	if (stream->runtime->total_bytes_available ==
200 				stream->runtime->total_bytes_transferred) {
201 		if (stream->direction == SND_COMPRESS_PLAYBACK) {
202 			pr_debug("both pointers are same, returning full avail\n");
203 			return stream->runtime->buffer_size;
204 		} else {
205 			pr_debug("both pointers are same, returning no avail\n");
206 			return 0;
207 		}
208 	}
209 
210 	avail->avail = stream->runtime->total_bytes_available -
211 			stream->runtime->total_bytes_transferred;
212 	if (stream->direction == SND_COMPRESS_PLAYBACK)
213 		avail->avail = stream->runtime->buffer_size - avail->avail;
214 
215 	pr_debug("ret avail as %lld\n", avail->avail);
216 	return avail->avail;
217 }
218 
219 static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
220 {
221 	struct snd_compr_avail avail;
222 
223 	return snd_compr_calc_avail(stream, &avail);
224 }
225 
226 static int
227 snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
228 {
229 	struct snd_compr_avail ioctl_avail;
230 	size_t avail;
231 
232 	avail = snd_compr_calc_avail(stream, &ioctl_avail);
233 	ioctl_avail.avail = avail;
234 
235 	switch (stream->runtime->state) {
236 	case SNDRV_PCM_STATE_OPEN:
237 		return -EBADFD;
238 	case SNDRV_PCM_STATE_XRUN:
239 		return -EPIPE;
240 	default:
241 		break;
242 	}
243 
244 	if (copy_to_user((__u64 __user *)arg,
245 				&ioctl_avail, sizeof(ioctl_avail)))
246 		return -EFAULT;
247 	return 0;
248 }
249 
250 static int snd_compr_write_data(struct snd_compr_stream *stream,
251 	       const char __user *buf, size_t count)
252 {
253 	void *dstn;
254 	size_t copy;
255 	struct snd_compr_runtime *runtime = stream->runtime;
256 	/* 64-bit Modulus */
257 	u64 app_pointer = div64_u64(runtime->total_bytes_available,
258 				    runtime->buffer_size);
259 	app_pointer = runtime->total_bytes_available -
260 		      (app_pointer * runtime->buffer_size);
261 
262 	dstn = runtime->buffer + app_pointer;
263 	pr_debug("copying %ld at %lld\n",
264 			(unsigned long)count, app_pointer);
265 	if (count < runtime->buffer_size - app_pointer) {
266 		if (copy_from_user(dstn, buf, count))
267 			return -EFAULT;
268 	} else {
269 		copy = runtime->buffer_size - app_pointer;
270 		if (copy_from_user(dstn, buf, copy))
271 			return -EFAULT;
272 		if (copy_from_user(runtime->buffer, buf + copy, count - copy))
273 			return -EFAULT;
274 	}
275 	/* if DSP cares, let it know data has been written */
276 	if (stream->ops->ack)
277 		stream->ops->ack(stream, count);
278 	return count;
279 }
280 
281 static ssize_t snd_compr_write(struct file *f, const char __user *buf,
282 		size_t count, loff_t *offset)
283 {
284 	struct snd_compr_file *data = f->private_data;
285 	struct snd_compr_stream *stream;
286 	size_t avail;
287 	int retval;
288 
289 	if (snd_BUG_ON(!data))
290 		return -EFAULT;
291 
292 	stream = &data->stream;
293 	mutex_lock(&stream->device->lock);
294 	/* write is allowed when stream is running or has been steup */
295 	switch (stream->runtime->state) {
296 	case SNDRV_PCM_STATE_SETUP:
297 	case SNDRV_PCM_STATE_PREPARED:
298 	case SNDRV_PCM_STATE_RUNNING:
299 		break;
300 	default:
301 		mutex_unlock(&stream->device->lock);
302 		return -EBADFD;
303 	}
304 
305 	avail = snd_compr_get_avail(stream);
306 	pr_debug("avail returned %ld\n", (unsigned long)avail);
307 	/* calculate how much we can write to buffer */
308 	if (avail > count)
309 		avail = count;
310 
311 	if (stream->ops->copy) {
312 		char __user* cbuf = (char __user*)buf;
313 		retval = stream->ops->copy(stream, cbuf, avail);
314 	} else {
315 		retval = snd_compr_write_data(stream, buf, avail);
316 	}
317 	if (retval > 0)
318 		stream->runtime->total_bytes_available += retval;
319 
320 	/* while initiating the stream, write should be called before START
321 	 * call, so in setup move state */
322 	if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
323 		stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
324 		pr_debug("stream prepared, Houston we are good to go\n");
325 	}
326 
327 	mutex_unlock(&stream->device->lock);
328 	return retval;
329 }
330 
331 
332 static ssize_t snd_compr_read(struct file *f, char __user *buf,
333 		size_t count, loff_t *offset)
334 {
335 	struct snd_compr_file *data = f->private_data;
336 	struct snd_compr_stream *stream;
337 	size_t avail;
338 	int retval;
339 
340 	if (snd_BUG_ON(!data))
341 		return -EFAULT;
342 
343 	stream = &data->stream;
344 	mutex_lock(&stream->device->lock);
345 
346 	/* read is allowed when stream is running, paused, draining and setup
347 	 * (yes setup is state which we transition to after stop, so if user
348 	 * wants to read data after stop we allow that)
349 	 */
350 	switch (stream->runtime->state) {
351 	case SNDRV_PCM_STATE_OPEN:
352 	case SNDRV_PCM_STATE_PREPARED:
353 	case SNDRV_PCM_STATE_SUSPENDED:
354 	case SNDRV_PCM_STATE_DISCONNECTED:
355 		retval = -EBADFD;
356 		goto out;
357 	case SNDRV_PCM_STATE_XRUN:
358 		retval = -EPIPE;
359 		goto out;
360 	}
361 
362 	avail = snd_compr_get_avail(stream);
363 	pr_debug("avail returned %ld\n", (unsigned long)avail);
364 	/* calculate how much we can read from buffer */
365 	if (avail > count)
366 		avail = count;
367 
368 	if (stream->ops->copy) {
369 		retval = stream->ops->copy(stream, buf, avail);
370 	} else {
371 		retval = -ENXIO;
372 		goto out;
373 	}
374 	if (retval > 0)
375 		stream->runtime->total_bytes_transferred += retval;
376 
377 out:
378 	mutex_unlock(&stream->device->lock);
379 	return retval;
380 }
381 
382 static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
383 {
384 	return -ENXIO;
385 }
386 
387 static __poll_t snd_compr_get_poll(struct snd_compr_stream *stream)
388 {
389 	if (stream->direction == SND_COMPRESS_PLAYBACK)
390 		return EPOLLOUT | EPOLLWRNORM;
391 	else
392 		return EPOLLIN | EPOLLRDNORM;
393 }
394 
395 static __poll_t snd_compr_poll(struct file *f, poll_table *wait)
396 {
397 	struct snd_compr_file *data = f->private_data;
398 	struct snd_compr_stream *stream;
399 	size_t avail;
400 	__poll_t retval = 0;
401 
402 	if (snd_BUG_ON(!data))
403 		return EPOLLERR;
404 
405 	stream = &data->stream;
406 
407 	mutex_lock(&stream->device->lock);
408 
409 	switch (stream->runtime->state) {
410 	case SNDRV_PCM_STATE_OPEN:
411 	case SNDRV_PCM_STATE_XRUN:
412 		retval = snd_compr_get_poll(stream) | EPOLLERR;
413 		goto out;
414 	default:
415 		break;
416 	}
417 
418 	poll_wait(f, &stream->runtime->sleep, wait);
419 
420 	avail = snd_compr_get_avail(stream);
421 	pr_debug("avail is %ld\n", (unsigned long)avail);
422 	/* check if we have at least one fragment to fill */
423 	switch (stream->runtime->state) {
424 	case SNDRV_PCM_STATE_DRAINING:
425 		/* stream has been woken up after drain is complete
426 		 * draining done so set stream state to stopped
427 		 */
428 		retval = snd_compr_get_poll(stream);
429 		stream->runtime->state = SNDRV_PCM_STATE_SETUP;
430 		break;
431 	case SNDRV_PCM_STATE_RUNNING:
432 	case SNDRV_PCM_STATE_PREPARED:
433 	case SNDRV_PCM_STATE_PAUSED:
434 		if (avail >= stream->runtime->fragment_size)
435 			retval = snd_compr_get_poll(stream);
436 		break;
437 	default:
438 		retval = snd_compr_get_poll(stream) | EPOLLERR;
439 		break;
440 	}
441 out:
442 	mutex_unlock(&stream->device->lock);
443 	return retval;
444 }
445 
446 static int
447 snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
448 {
449 	int retval;
450 	struct snd_compr_caps caps;
451 
452 	if (!stream->ops->get_caps)
453 		return -ENXIO;
454 
455 	memset(&caps, 0, sizeof(caps));
456 	retval = stream->ops->get_caps(stream, &caps);
457 	if (retval)
458 		goto out;
459 	if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
460 		retval = -EFAULT;
461 out:
462 	return retval;
463 }
464 
465 #ifndef COMPR_CODEC_CAPS_OVERFLOW
466 static int
467 snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
468 {
469 	int retval;
470 	struct snd_compr_codec_caps *caps;
471 
472 	if (!stream->ops->get_codec_caps)
473 		return -ENXIO;
474 
475 	caps = kzalloc(sizeof(*caps), GFP_KERNEL);
476 	if (!caps)
477 		return -ENOMEM;
478 
479 	retval = stream->ops->get_codec_caps(stream, caps);
480 	if (retval)
481 		goto out;
482 	if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
483 		retval = -EFAULT;
484 
485 out:
486 	kfree(caps);
487 	return retval;
488 }
489 #endif /* !COMPR_CODEC_CAPS_OVERFLOW */
490 
491 int snd_compr_malloc_pages(struct snd_compr_stream *stream, size_t size)
492 {
493 	struct snd_dma_buffer *dmab;
494 	int ret;
495 
496 	if (snd_BUG_ON(!(stream) || !(stream)->runtime))
497 		return -EINVAL;
498 	dmab = kzalloc(sizeof(*dmab), GFP_KERNEL);
499 	if (!dmab)
500 		return -ENOMEM;
501 	dmab->dev = stream->dma_buffer.dev;
502 	ret = snd_dma_alloc_pages(dmab->dev.type, dmab->dev.dev, size, dmab);
503 	if (ret < 0) {
504 		kfree(dmab);
505 		return ret;
506 	}
507 
508 	snd_compr_set_runtime_buffer(stream, dmab);
509 	stream->runtime->dma_bytes = size;
510 	return 1;
511 }
512 EXPORT_SYMBOL(snd_compr_malloc_pages);
513 
514 int snd_compr_free_pages(struct snd_compr_stream *stream)
515 {
516 	struct snd_compr_runtime *runtime = stream->runtime;
517 
518 	if (snd_BUG_ON(!(stream) || !(stream)->runtime))
519 		return -EINVAL;
520 	if (runtime->dma_area == NULL)
521 		return 0;
522 	if (runtime->dma_buffer_p != &stream->dma_buffer) {
523 		/* It's a newly allocated buffer. Release it now. */
524 		snd_dma_free_pages(runtime->dma_buffer_p);
525 		kfree(runtime->dma_buffer_p);
526 	}
527 
528 	snd_compr_set_runtime_buffer(stream, NULL);
529 	return 0;
530 }
531 EXPORT_SYMBOL(snd_compr_free_pages);
532 
533 /* revisit this with snd_pcm_preallocate_xxx */
534 static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
535 		struct snd_compr_params *params)
536 {
537 	unsigned int buffer_size;
538 	void *buffer = NULL;
539 
540 	buffer_size = params->buffer.fragment_size * params->buffer.fragments;
541 	if (stream->ops->copy) {
542 		buffer = NULL;
543 		/* if copy is defined the driver will be required to copy
544 		 * the data from core
545 		 */
546 	} else {
547 		if (stream->runtime->dma_buffer_p) {
548 
549 			if (buffer_size > stream->runtime->dma_buffer_p->bytes)
550 				dev_err(&stream->device->dev,
551 						"Not enough DMA buffer");
552 			else
553 				buffer = stream->runtime->dma_buffer_p->area;
554 
555 		} else {
556 			buffer = kmalloc(buffer_size, GFP_KERNEL);
557 		}
558 
559 		if (!buffer)
560 			return -ENOMEM;
561 	}
562 	stream->runtime->fragment_size = params->buffer.fragment_size;
563 	stream->runtime->fragments = params->buffer.fragments;
564 	stream->runtime->buffer = buffer;
565 	stream->runtime->buffer_size = buffer_size;
566 	return 0;
567 }
568 
569 static int snd_compress_check_input(struct snd_compr_params *params)
570 {
571 	/* first let's check the buffer parameter's */
572 	if (params->buffer.fragment_size == 0 ||
573 	    params->buffer.fragments > U32_MAX / params->buffer.fragment_size ||
574 	    params->buffer.fragments == 0)
575 		return -EINVAL;
576 
577 	/* now codec parameters */
578 	if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
579 		return -EINVAL;
580 
581 	if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
582 		return -EINVAL;
583 
584 	return 0;
585 }
586 
587 static int
588 snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
589 {
590 	struct snd_compr_params *params;
591 	int retval;
592 
593 	if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
594 		/*
595 		 * we should allow parameter change only when stream has been
596 		 * opened not in other cases
597 		 */
598 		params = memdup_user((void __user *)arg, sizeof(*params));
599 		if (IS_ERR(params))
600 			return PTR_ERR(params);
601 
602 		retval = snd_compress_check_input(params);
603 		if (retval)
604 			goto out;
605 
606 		retval = snd_compr_allocate_buffer(stream, params);
607 		if (retval) {
608 			retval = -ENOMEM;
609 			goto out;
610 		}
611 
612 		retval = stream->ops->set_params(stream, params);
613 		if (retval)
614 			goto out;
615 
616 		stream->metadata_set = false;
617 		stream->next_track = false;
618 
619 		stream->runtime->state = SNDRV_PCM_STATE_SETUP;
620 	} else {
621 		return -EPERM;
622 	}
623 out:
624 	kfree(params);
625 	return retval;
626 }
627 
628 static int
629 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
630 {
631 	struct snd_codec *params;
632 	int retval;
633 
634 	if (!stream->ops->get_params)
635 		return -EBADFD;
636 
637 	params = kzalloc(sizeof(*params), GFP_KERNEL);
638 	if (!params)
639 		return -ENOMEM;
640 	retval = stream->ops->get_params(stream, params);
641 	if (retval)
642 		goto out;
643 	if (copy_to_user((char __user *)arg, params, sizeof(*params)))
644 		retval = -EFAULT;
645 
646 out:
647 	kfree(params);
648 	return retval;
649 }
650 
651 static int
652 snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
653 {
654 	struct snd_compr_metadata metadata;
655 	int retval;
656 
657 	if (!stream->ops->get_metadata)
658 		return -ENXIO;
659 
660 	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
661 		return -EFAULT;
662 
663 	retval = stream->ops->get_metadata(stream, &metadata);
664 	if (retval != 0)
665 		return retval;
666 
667 	if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
668 		return -EFAULT;
669 
670 	return 0;
671 }
672 
673 static int
674 snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
675 {
676 	struct snd_compr_metadata metadata;
677 	int retval;
678 
679 	if (!stream->ops->set_metadata)
680 		return -ENXIO;
681 	/*
682 	* we should allow parameter change only when stream has been
683 	* opened not in other cases
684 	*/
685 	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
686 		return -EFAULT;
687 
688 	retval = stream->ops->set_metadata(stream, &metadata);
689 	stream->metadata_set = true;
690 
691 	return retval;
692 }
693 
694 static inline int
695 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
696 {
697 	struct snd_compr_tstamp tstamp = {0};
698 	int ret;
699 
700 	ret = snd_compr_update_tstamp(stream, &tstamp);
701 	if (ret == 0)
702 		ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
703 			&tstamp, sizeof(tstamp)) ? -EFAULT : 0;
704 	return ret;
705 }
706 
707 static int snd_compr_pause(struct snd_compr_stream *stream)
708 {
709 	int retval;
710 
711 	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
712 		return -EPERM;
713 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
714 	if (!retval)
715 		stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
716 	return retval;
717 }
718 
719 static int snd_compr_resume(struct snd_compr_stream *stream)
720 {
721 	int retval;
722 
723 	if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
724 		return -EPERM;
725 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
726 	if (!retval)
727 		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
728 	return retval;
729 }
730 
731 static int snd_compr_start(struct snd_compr_stream *stream)
732 {
733 	int retval;
734 
735 	switch (stream->runtime->state) {
736 	case SNDRV_PCM_STATE_SETUP:
737 		if (stream->direction != SND_COMPRESS_CAPTURE)
738 			return -EPERM;
739 		break;
740 	case SNDRV_PCM_STATE_PREPARED:
741 		break;
742 	default:
743 		return -EPERM;
744 	}
745 
746 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
747 	if (!retval)
748 		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
749 	return retval;
750 }
751 
752 static int snd_compr_stop(struct snd_compr_stream *stream)
753 {
754 	int retval;
755 
756 	switch (stream->runtime->state) {
757 	case SNDRV_PCM_STATE_OPEN:
758 	case SNDRV_PCM_STATE_SETUP:
759 	case SNDRV_PCM_STATE_PREPARED:
760 		return -EPERM;
761 	default:
762 		break;
763 	}
764 
765 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
766 	if (!retval) {
767 		snd_compr_drain_notify(stream);
768 		stream->runtime->total_bytes_available = 0;
769 		stream->runtime->total_bytes_transferred = 0;
770 	}
771 	return retval;
772 }
773 
774 static void error_delayed_work(struct work_struct *work)
775 {
776 	struct snd_compr_stream *stream;
777 
778 	stream = container_of(work, struct snd_compr_stream, error_work.work);
779 
780 	mutex_lock(&stream->device->lock);
781 
782 	stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
783 	wake_up(&stream->runtime->sleep);
784 
785 	mutex_unlock(&stream->device->lock);
786 }
787 
788 /*
789  * snd_compr_stop_error: Report a fatal error on a stream
790  * @stream: pointer to stream
791  * @state: state to transition the stream to
792  *
793  * Stop the stream and set its state.
794  *
795  * Should be called with compressed device lock held.
796  */
797 int snd_compr_stop_error(struct snd_compr_stream *stream,
798 			 snd_pcm_state_t state)
799 {
800 	if (stream->runtime->state == state)
801 		return 0;
802 
803 	stream->runtime->state = state;
804 
805 	pr_debug("Changing state to: %d\n", state);
806 
807 	queue_delayed_work(system_power_efficient_wq, &stream->error_work, 0);
808 
809 	return 0;
810 }
811 EXPORT_SYMBOL_GPL(snd_compr_stop_error);
812 
813 static int snd_compress_wait_for_drain(struct snd_compr_stream *stream)
814 {
815 	int ret;
816 
817 	/*
818 	 * We are called with lock held. So drop the lock while we wait for
819 	 * drain complete notification from the driver
820 	 *
821 	 * It is expected that driver will notify the drain completion and then
822 	 * stream will be moved to SETUP state, even if draining resulted in an
823 	 * error. We can trigger next track after this.
824 	 */
825 	stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
826 	mutex_unlock(&stream->device->lock);
827 
828 	/* we wait for drain to complete here, drain can return when
829 	 * interruption occurred, wait returned error or success.
830 	 * For the first two cases we don't do anything different here and
831 	 * return after waking up
832 	 */
833 
834 	ret = wait_event_interruptible(stream->runtime->sleep,
835 			(stream->runtime->state != SNDRV_PCM_STATE_DRAINING));
836 	if (ret == -ERESTARTSYS)
837 		pr_debug("wait aborted by a signal\n");
838 	else if (ret)
839 		pr_debug("wait for drain failed with %d\n", ret);
840 
841 
842 	wake_up(&stream->runtime->sleep);
843 	mutex_lock(&stream->device->lock);
844 
845 	return ret;
846 }
847 
848 static int snd_compr_drain(struct snd_compr_stream *stream)
849 {
850 	int retval;
851 
852 	switch (stream->runtime->state) {
853 	case SNDRV_PCM_STATE_OPEN:
854 	case SNDRV_PCM_STATE_SETUP:
855 	case SNDRV_PCM_STATE_PREPARED:
856 	case SNDRV_PCM_STATE_PAUSED:
857 		return -EPERM;
858 	case SNDRV_PCM_STATE_XRUN:
859 		return -EPIPE;
860 	default:
861 		break;
862 	}
863 
864 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
865 	if (retval) {
866 		pr_debug("SND_COMPR_TRIGGER_DRAIN failed %d\n", retval);
867 		wake_up(&stream->runtime->sleep);
868 		return retval;
869 	}
870 
871 	return snd_compress_wait_for_drain(stream);
872 }
873 
874 static int snd_compr_next_track(struct snd_compr_stream *stream)
875 {
876 	int retval;
877 
878 	/* only a running stream can transition to next track */
879 	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
880 		return -EPERM;
881 
882 	/* next track doesn't have any meaning for capture streams */
883 	if (stream->direction == SND_COMPRESS_CAPTURE)
884 		return -EPERM;
885 
886 	/* you can signal next track if this is intended to be a gapless stream
887 	 * and current track metadata is set
888 	 */
889 	if (stream->metadata_set == false)
890 		return -EPERM;
891 
892 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
893 	if (retval != 0)
894 		return retval;
895 	stream->metadata_set = false;
896 	stream->next_track = true;
897 	return 0;
898 }
899 
900 static int snd_compr_partial_drain(struct snd_compr_stream *stream)
901 {
902 	int retval;
903 
904 	switch (stream->runtime->state) {
905 	case SNDRV_PCM_STATE_OPEN:
906 	case SNDRV_PCM_STATE_SETUP:
907 	case SNDRV_PCM_STATE_PREPARED:
908 	case SNDRV_PCM_STATE_PAUSED:
909 		return -EPERM;
910 	case SNDRV_PCM_STATE_XRUN:
911 		return -EPIPE;
912 	default:
913 		break;
914 	}
915 
916 	/* partial drain doesn't have any meaning for capture streams */
917 	if (stream->direction == SND_COMPRESS_CAPTURE)
918 		return -EPERM;
919 
920 	/* stream can be drained only when next track has been signalled */
921 	if (stream->next_track == false)
922 		return -EPERM;
923 
924 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
925 	if (retval) {
926 		pr_debug("Partial drain returned failure\n");
927 		wake_up(&stream->runtime->sleep);
928 		return retval;
929 	}
930 
931 	stream->next_track = false;
932 	return snd_compress_wait_for_drain(stream);
933 }
934 
935 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
936 {
937 	struct snd_compr_file *data = f->private_data;
938 	struct snd_compr_stream *stream;
939 	int retval = -ENOTTY;
940 
941 	if (snd_BUG_ON(!data))
942 		return -EFAULT;
943 
944 	stream = &data->stream;
945 
946 	mutex_lock(&stream->device->lock);
947 	switch (_IOC_NR(cmd)) {
948 	case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
949 		retval = put_user(SNDRV_COMPRESS_VERSION,
950 				(int __user *)arg) ? -EFAULT : 0;
951 		break;
952 	case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
953 		retval = snd_compr_get_caps(stream, arg);
954 		break;
955 #ifndef COMPR_CODEC_CAPS_OVERFLOW
956 	case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
957 		retval = snd_compr_get_codec_caps(stream, arg);
958 		break;
959 #endif
960 	case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
961 		retval = snd_compr_set_params(stream, arg);
962 		break;
963 	case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
964 		retval = snd_compr_get_params(stream, arg);
965 		break;
966 	case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
967 		retval = snd_compr_set_metadata(stream, arg);
968 		break;
969 	case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
970 		retval = snd_compr_get_metadata(stream, arg);
971 		break;
972 	case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
973 		retval = snd_compr_tstamp(stream, arg);
974 		break;
975 	case _IOC_NR(SNDRV_COMPRESS_AVAIL):
976 		retval = snd_compr_ioctl_avail(stream, arg);
977 		break;
978 	case _IOC_NR(SNDRV_COMPRESS_PAUSE):
979 		retval = snd_compr_pause(stream);
980 		break;
981 	case _IOC_NR(SNDRV_COMPRESS_RESUME):
982 		retval = snd_compr_resume(stream);
983 		break;
984 	case _IOC_NR(SNDRV_COMPRESS_START):
985 		retval = snd_compr_start(stream);
986 		break;
987 	case _IOC_NR(SNDRV_COMPRESS_STOP):
988 		retval = snd_compr_stop(stream);
989 		break;
990 	case _IOC_NR(SNDRV_COMPRESS_DRAIN):
991 		retval = snd_compr_drain(stream);
992 		break;
993 	case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
994 		retval = snd_compr_partial_drain(stream);
995 		break;
996 	case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
997 		retval = snd_compr_next_track(stream);
998 		break;
999 
1000 	}
1001 	mutex_unlock(&stream->device->lock);
1002 	return retval;
1003 }
1004 
1005 /* support of 32bit userspace on 64bit platforms */
1006 #ifdef CONFIG_COMPAT
1007 static long snd_compr_ioctl_compat(struct file *file, unsigned int cmd,
1008 						unsigned long arg)
1009 {
1010 	return snd_compr_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
1011 }
1012 #endif
1013 
1014 static const struct file_operations snd_compr_file_ops = {
1015 		.owner =	THIS_MODULE,
1016 		.open =		snd_compr_open,
1017 		.release =	snd_compr_free,
1018 		.write =	snd_compr_write,
1019 		.read =		snd_compr_read,
1020 		.unlocked_ioctl = snd_compr_ioctl,
1021 #ifdef CONFIG_COMPAT
1022 		.compat_ioctl = snd_compr_ioctl_compat,
1023 #endif
1024 		.mmap =		snd_compr_mmap,
1025 		.poll =		snd_compr_poll,
1026 };
1027 
1028 static int snd_compress_dev_register(struct snd_device *device)
1029 {
1030 	int ret = -EINVAL;
1031 	struct snd_compr *compr;
1032 
1033 	if (snd_BUG_ON(!device || !device->device_data))
1034 		return -EBADFD;
1035 	compr = device->device_data;
1036 
1037 	pr_debug("reg device %s, direction %d\n", compr->name,
1038 			compr->direction);
1039 	/* register compressed device */
1040 	ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS,
1041 				  compr->card, compr->device,
1042 				  &snd_compr_file_ops, compr, &compr->dev);
1043 	if (ret < 0) {
1044 		pr_err("snd_register_device failed %d\n", ret);
1045 		return ret;
1046 	}
1047 	return ret;
1048 
1049 }
1050 
1051 static int snd_compress_dev_disconnect(struct snd_device *device)
1052 {
1053 	struct snd_compr *compr;
1054 
1055 	compr = device->device_data;
1056 	snd_unregister_device(&compr->dev);
1057 	return 0;
1058 }
1059 
1060 #ifdef CONFIG_SND_VERBOSE_PROCFS
1061 static void snd_compress_proc_info_read(struct snd_info_entry *entry,
1062 					struct snd_info_buffer *buffer)
1063 {
1064 	struct snd_compr *compr = (struct snd_compr *)entry->private_data;
1065 
1066 	snd_iprintf(buffer, "card: %d\n", compr->card->number);
1067 	snd_iprintf(buffer, "device: %d\n", compr->device);
1068 	snd_iprintf(buffer, "stream: %s\n",
1069 			compr->direction == SND_COMPRESS_PLAYBACK
1070 				? "PLAYBACK" : "CAPTURE");
1071 	snd_iprintf(buffer, "id: %s\n", compr->id);
1072 }
1073 
1074 static int snd_compress_proc_init(struct snd_compr *compr)
1075 {
1076 	struct snd_info_entry *entry;
1077 	char name[16];
1078 
1079 	sprintf(name, "compr%i", compr->device);
1080 	entry = snd_info_create_card_entry(compr->card, name,
1081 					   compr->card->proc_root);
1082 	if (!entry)
1083 		return -ENOMEM;
1084 	entry->mode = S_IFDIR | 0555;
1085 	compr->proc_root = entry;
1086 
1087 	entry = snd_info_create_card_entry(compr->card, "info",
1088 					   compr->proc_root);
1089 	if (entry)
1090 		snd_info_set_text_ops(entry, compr,
1091 				      snd_compress_proc_info_read);
1092 	compr->proc_info_entry = entry;
1093 
1094 	return 0;
1095 }
1096 
1097 static void snd_compress_proc_done(struct snd_compr *compr)
1098 {
1099 	snd_info_free_entry(compr->proc_info_entry);
1100 	compr->proc_info_entry = NULL;
1101 	snd_info_free_entry(compr->proc_root);
1102 	compr->proc_root = NULL;
1103 }
1104 
1105 static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
1106 {
1107 	strlcpy(compr->id, id, sizeof(compr->id));
1108 }
1109 #else
1110 static inline int snd_compress_proc_init(struct snd_compr *compr)
1111 {
1112 	return 0;
1113 }
1114 
1115 static inline void snd_compress_proc_done(struct snd_compr *compr)
1116 {
1117 }
1118 
1119 static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
1120 {
1121 }
1122 #endif
1123 
1124 static int snd_compress_dev_free(struct snd_device *device)
1125 {
1126 	struct snd_compr *compr;
1127 
1128 	compr = device->device_data;
1129 	snd_compress_proc_done(compr);
1130 	put_device(&compr->dev);
1131 	return 0;
1132 }
1133 
1134 /*
1135  * snd_compress_new: create new compress device
1136  * @card: sound card pointer
1137  * @device: device number
1138  * @dirn: device direction, should be of type enum snd_compr_direction
1139  * @compr: compress device pointer
1140  */
1141 int snd_compress_new(struct snd_card *card, int device,
1142 			int dirn, const char *id, struct snd_compr *compr)
1143 {
1144 	static const struct snd_device_ops ops = {
1145 		.dev_free = snd_compress_dev_free,
1146 		.dev_register = snd_compress_dev_register,
1147 		.dev_disconnect = snd_compress_dev_disconnect,
1148 	};
1149 	int ret;
1150 
1151 	compr->card = card;
1152 	compr->device = device;
1153 	compr->direction = dirn;
1154 
1155 	snd_compress_set_id(compr, id);
1156 
1157 	snd_device_initialize(&compr->dev, card);
1158 	dev_set_name(&compr->dev, "comprC%iD%i", card->number, device);
1159 
1160 	ret = snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
1161 	if (ret == 0)
1162 		snd_compress_proc_init(compr);
1163 
1164 	return ret;
1165 }
1166 EXPORT_SYMBOL_GPL(snd_compress_new);
1167 
1168 static int snd_compress_add_device(struct snd_compr *device)
1169 {
1170 	int ret;
1171 
1172 	if (!device->card)
1173 		return -EINVAL;
1174 
1175 	/* register the card */
1176 	ret = snd_card_register(device->card);
1177 	if (ret)
1178 		goto out;
1179 	return 0;
1180 
1181 out:
1182 	pr_err("failed with %d\n", ret);
1183 	return ret;
1184 
1185 }
1186 
1187 static int snd_compress_remove_device(struct snd_compr *device)
1188 {
1189 	return snd_card_free(device->card);
1190 }
1191 
1192 /**
1193  * snd_compress_register - register compressed device
1194  *
1195  * @device: compressed device to register
1196  */
1197 int snd_compress_register(struct snd_compr *device)
1198 {
1199 	int retval;
1200 
1201 	if (device->name == NULL || device->ops == NULL)
1202 		return -EINVAL;
1203 
1204 	pr_debug("Registering compressed device %s\n", device->name);
1205 	if (snd_BUG_ON(!device->ops->open))
1206 		return -EINVAL;
1207 	if (snd_BUG_ON(!device->ops->free))
1208 		return -EINVAL;
1209 	if (snd_BUG_ON(!device->ops->set_params))
1210 		return -EINVAL;
1211 	if (snd_BUG_ON(!device->ops->trigger))
1212 		return -EINVAL;
1213 
1214 	mutex_init(&device->lock);
1215 
1216 	/* register a compressed card */
1217 	mutex_lock(&device_mutex);
1218 	retval = snd_compress_add_device(device);
1219 	mutex_unlock(&device_mutex);
1220 	return retval;
1221 }
1222 EXPORT_SYMBOL_GPL(snd_compress_register);
1223 
1224 int snd_compress_deregister(struct snd_compr *device)
1225 {
1226 	pr_debug("Removing compressed device %s\n", device->name);
1227 	mutex_lock(&device_mutex);
1228 	snd_compress_remove_device(device);
1229 	mutex_unlock(&device_mutex);
1230 	return 0;
1231 }
1232 EXPORT_SYMBOL_GPL(snd_compress_deregister);
1233 
1234 MODULE_DESCRIPTION("ALSA Compressed offload framework");
1235 MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
1236 MODULE_LICENSE("GPL v2");
1237