xref: /openbmc/linux/sound/core/compress_offload.c (revision 6db6b729)
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 struct snd_compr_file {
51 	unsigned long caps;
52 	struct snd_compr_stream stream;
53 };
54 
55 static void error_delayed_work(struct work_struct *work);
56 
57 /*
58  * a note on stream states used:
59  * we use following states in the compressed core
60  * SNDRV_PCM_STATE_OPEN: When stream has been opened.
61  * SNDRV_PCM_STATE_SETUP: When stream has been initialized. This is done by
62  *	calling SNDRV_COMPRESS_SET_PARAMS. Running streams will come to this
63  *	state at stop by calling SNDRV_COMPRESS_STOP, or at end of drain.
64  * SNDRV_PCM_STATE_PREPARED: When a stream has been written to (for
65  *	playback only). User after setting up stream writes the data buffer
66  *	before starting the stream.
67  * SNDRV_PCM_STATE_RUNNING: When stream has been started and is
68  *	decoding/encoding and rendering/capturing data.
69  * SNDRV_PCM_STATE_DRAINING: When stream is draining current data. This is done
70  *	by calling SNDRV_COMPRESS_DRAIN.
71  * SNDRV_PCM_STATE_PAUSED: When stream is paused. This is done by calling
72  *	SNDRV_COMPRESS_PAUSE. It can be stopped or resumed by calling
73  *	SNDRV_COMPRESS_STOP or SNDRV_COMPRESS_RESUME respectively.
74  */
75 static int snd_compr_open(struct inode *inode, struct file *f)
76 {
77 	struct snd_compr *compr;
78 	struct snd_compr_file *data;
79 	struct snd_compr_runtime *runtime;
80 	enum snd_compr_direction dirn;
81 	int maj = imajor(inode);
82 	int ret;
83 
84 	if ((f->f_flags & O_ACCMODE) == O_WRONLY)
85 		dirn = SND_COMPRESS_PLAYBACK;
86 	else if ((f->f_flags & O_ACCMODE) == O_RDONLY)
87 		dirn = SND_COMPRESS_CAPTURE;
88 	else
89 		return -EINVAL;
90 
91 	if (maj == snd_major)
92 		compr = snd_lookup_minor_data(iminor(inode),
93 					SNDRV_DEVICE_TYPE_COMPRESS);
94 	else
95 		return -EBADFD;
96 
97 	if (compr == NULL) {
98 		pr_err("no device data!!!\n");
99 		return -ENODEV;
100 	}
101 
102 	if (dirn != compr->direction) {
103 		pr_err("this device doesn't support this direction\n");
104 		snd_card_unref(compr->card);
105 		return -EINVAL;
106 	}
107 
108 	data = kzalloc(sizeof(*data), GFP_KERNEL);
109 	if (!data) {
110 		snd_card_unref(compr->card);
111 		return -ENOMEM;
112 	}
113 
114 	INIT_DELAYED_WORK(&data->stream.error_work, error_delayed_work);
115 
116 	data->stream.ops = compr->ops;
117 	data->stream.direction = dirn;
118 	data->stream.private_data = compr->private_data;
119 	data->stream.device = compr;
120 	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
121 	if (!runtime) {
122 		kfree(data);
123 		snd_card_unref(compr->card);
124 		return -ENOMEM;
125 	}
126 	runtime->state = SNDRV_PCM_STATE_OPEN;
127 	init_waitqueue_head(&runtime->sleep);
128 	data->stream.runtime = runtime;
129 	f->private_data = (void *)data;
130 	mutex_lock(&compr->lock);
131 	ret = compr->ops->open(&data->stream);
132 	mutex_unlock(&compr->lock);
133 	if (ret) {
134 		kfree(runtime);
135 		kfree(data);
136 	}
137 	snd_card_unref(compr->card);
138 	return ret;
139 }
140 
141 static int snd_compr_free(struct inode *inode, struct file *f)
142 {
143 	struct snd_compr_file *data = f->private_data;
144 	struct snd_compr_runtime *runtime = data->stream.runtime;
145 
146 	cancel_delayed_work_sync(&data->stream.error_work);
147 
148 	switch (runtime->state) {
149 	case SNDRV_PCM_STATE_RUNNING:
150 	case SNDRV_PCM_STATE_DRAINING:
151 	case SNDRV_PCM_STATE_PAUSED:
152 		data->stream.ops->trigger(&data->stream, SNDRV_PCM_TRIGGER_STOP);
153 		break;
154 	default:
155 		break;
156 	}
157 
158 	data->stream.ops->free(&data->stream);
159 	if (!data->stream.runtime->dma_buffer_p)
160 		kfree(data->stream.runtime->buffer);
161 	kfree(data->stream.runtime);
162 	kfree(data);
163 	return 0;
164 }
165 
166 static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
167 		struct snd_compr_tstamp *tstamp)
168 {
169 	if (!stream->ops->pointer)
170 		return -ENOTSUPP;
171 	stream->ops->pointer(stream, tstamp);
172 	pr_debug("dsp consumed till %d total %d bytes\n",
173 		tstamp->byte_offset, tstamp->copied_total);
174 	if (stream->direction == SND_COMPRESS_PLAYBACK)
175 		stream->runtime->total_bytes_transferred = tstamp->copied_total;
176 	else
177 		stream->runtime->total_bytes_available = tstamp->copied_total;
178 	return 0;
179 }
180 
181 static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
182 		struct snd_compr_avail *avail)
183 {
184 	memset(avail, 0, sizeof(*avail));
185 	snd_compr_update_tstamp(stream, &avail->tstamp);
186 	/* Still need to return avail even if tstamp can't be filled in */
187 
188 	if (stream->runtime->total_bytes_available == 0 &&
189 			stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
190 			stream->direction == SND_COMPRESS_PLAYBACK) {
191 		pr_debug("detected init and someone forgot to do a write\n");
192 		return stream->runtime->buffer_size;
193 	}
194 	pr_debug("app wrote %lld, DSP consumed %lld\n",
195 			stream->runtime->total_bytes_available,
196 			stream->runtime->total_bytes_transferred);
197 	if (stream->runtime->total_bytes_available ==
198 				stream->runtime->total_bytes_transferred) {
199 		if (stream->direction == SND_COMPRESS_PLAYBACK) {
200 			pr_debug("both pointers are same, returning full avail\n");
201 			return stream->runtime->buffer_size;
202 		} else {
203 			pr_debug("both pointers are same, returning no avail\n");
204 			return 0;
205 		}
206 	}
207 
208 	avail->avail = stream->runtime->total_bytes_available -
209 			stream->runtime->total_bytes_transferred;
210 	if (stream->direction == SND_COMPRESS_PLAYBACK)
211 		avail->avail = stream->runtime->buffer_size - avail->avail;
212 
213 	pr_debug("ret avail as %lld\n", avail->avail);
214 	return avail->avail;
215 }
216 
217 static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
218 {
219 	struct snd_compr_avail avail;
220 
221 	return snd_compr_calc_avail(stream, &avail);
222 }
223 
224 static int
225 snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
226 {
227 	struct snd_compr_avail ioctl_avail;
228 	size_t avail;
229 
230 	avail = snd_compr_calc_avail(stream, &ioctl_avail);
231 	ioctl_avail.avail = avail;
232 
233 	switch (stream->runtime->state) {
234 	case SNDRV_PCM_STATE_OPEN:
235 		return -EBADFD;
236 	case SNDRV_PCM_STATE_XRUN:
237 		return -EPIPE;
238 	default:
239 		break;
240 	}
241 
242 	if (copy_to_user((__u64 __user *)arg,
243 				&ioctl_avail, sizeof(ioctl_avail)))
244 		return -EFAULT;
245 	return 0;
246 }
247 
248 static int snd_compr_write_data(struct snd_compr_stream *stream,
249 	       const char __user *buf, size_t count)
250 {
251 	void *dstn;
252 	size_t copy;
253 	struct snd_compr_runtime *runtime = stream->runtime;
254 	/* 64-bit Modulus */
255 	u64 app_pointer = div64_u64(runtime->total_bytes_available,
256 				    runtime->buffer_size);
257 	app_pointer = runtime->total_bytes_available -
258 		      (app_pointer * runtime->buffer_size);
259 
260 	dstn = runtime->buffer + app_pointer;
261 	pr_debug("copying %ld at %lld\n",
262 			(unsigned long)count, app_pointer);
263 	if (count < runtime->buffer_size - app_pointer) {
264 		if (copy_from_user(dstn, buf, count))
265 			return -EFAULT;
266 	} else {
267 		copy = runtime->buffer_size - app_pointer;
268 		if (copy_from_user(dstn, buf, copy))
269 			return -EFAULT;
270 		if (copy_from_user(runtime->buffer, buf + copy, count - copy))
271 			return -EFAULT;
272 	}
273 	/* if DSP cares, let it know data has been written */
274 	if (stream->ops->ack)
275 		stream->ops->ack(stream, count);
276 	return count;
277 }
278 
279 static ssize_t snd_compr_write(struct file *f, const char __user *buf,
280 		size_t count, loff_t *offset)
281 {
282 	struct snd_compr_file *data = f->private_data;
283 	struct snd_compr_stream *stream;
284 	size_t avail;
285 	int retval;
286 
287 	if (snd_BUG_ON(!data))
288 		return -EFAULT;
289 
290 	stream = &data->stream;
291 	mutex_lock(&stream->device->lock);
292 	/* write is allowed when stream is running or has been steup */
293 	switch (stream->runtime->state) {
294 	case SNDRV_PCM_STATE_SETUP:
295 	case SNDRV_PCM_STATE_PREPARED:
296 	case SNDRV_PCM_STATE_RUNNING:
297 		break;
298 	default:
299 		mutex_unlock(&stream->device->lock);
300 		return -EBADFD;
301 	}
302 
303 	avail = snd_compr_get_avail(stream);
304 	pr_debug("avail returned %ld\n", (unsigned long)avail);
305 	/* calculate how much we can write to buffer */
306 	if (avail > count)
307 		avail = count;
308 
309 	if (stream->ops->copy) {
310 		char __user* cbuf = (char __user*)buf;
311 		retval = stream->ops->copy(stream, cbuf, avail);
312 	} else {
313 		retval = snd_compr_write_data(stream, buf, avail);
314 	}
315 	if (retval > 0)
316 		stream->runtime->total_bytes_available += retval;
317 
318 	/* while initiating the stream, write should be called before START
319 	 * call, so in setup move state */
320 	if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
321 		stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
322 		pr_debug("stream prepared, Houston we are good to go\n");
323 	}
324 
325 	mutex_unlock(&stream->device->lock);
326 	return retval;
327 }
328 
329 
330 static ssize_t snd_compr_read(struct file *f, char __user *buf,
331 		size_t count, loff_t *offset)
332 {
333 	struct snd_compr_file *data = f->private_data;
334 	struct snd_compr_stream *stream;
335 	size_t avail;
336 	int retval;
337 
338 	if (snd_BUG_ON(!data))
339 		return -EFAULT;
340 
341 	stream = &data->stream;
342 	mutex_lock(&stream->device->lock);
343 
344 	/* read is allowed when stream is running, paused, draining and setup
345 	 * (yes setup is state which we transition to after stop, so if user
346 	 * wants to read data after stop we allow that)
347 	 */
348 	switch (stream->runtime->state) {
349 	case SNDRV_PCM_STATE_OPEN:
350 	case SNDRV_PCM_STATE_PREPARED:
351 	case SNDRV_PCM_STATE_SUSPENDED:
352 	case SNDRV_PCM_STATE_DISCONNECTED:
353 		retval = -EBADFD;
354 		goto out;
355 	case SNDRV_PCM_STATE_XRUN:
356 		retval = -EPIPE;
357 		goto out;
358 	}
359 
360 	avail = snd_compr_get_avail(stream);
361 	pr_debug("avail returned %ld\n", (unsigned long)avail);
362 	/* calculate how much we can read from buffer */
363 	if (avail > count)
364 		avail = count;
365 
366 	if (stream->ops->copy) {
367 		retval = stream->ops->copy(stream, buf, avail);
368 	} else {
369 		retval = -ENXIO;
370 		goto out;
371 	}
372 	if (retval > 0)
373 		stream->runtime->total_bytes_transferred += retval;
374 
375 out:
376 	mutex_unlock(&stream->device->lock);
377 	return retval;
378 }
379 
380 static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
381 {
382 	return -ENXIO;
383 }
384 
385 static __poll_t snd_compr_get_poll(struct snd_compr_stream *stream)
386 {
387 	if (stream->direction == SND_COMPRESS_PLAYBACK)
388 		return EPOLLOUT | EPOLLWRNORM;
389 	else
390 		return EPOLLIN | EPOLLRDNORM;
391 }
392 
393 static __poll_t snd_compr_poll(struct file *f, poll_table *wait)
394 {
395 	struct snd_compr_file *data = f->private_data;
396 	struct snd_compr_stream *stream;
397 	size_t avail;
398 	__poll_t retval = 0;
399 
400 	if (snd_BUG_ON(!data))
401 		return EPOLLERR;
402 
403 	stream = &data->stream;
404 
405 	mutex_lock(&stream->device->lock);
406 
407 	switch (stream->runtime->state) {
408 	case SNDRV_PCM_STATE_OPEN:
409 	case SNDRV_PCM_STATE_XRUN:
410 		retval = snd_compr_get_poll(stream) | EPOLLERR;
411 		goto out;
412 	default:
413 		break;
414 	}
415 
416 	poll_wait(f, &stream->runtime->sleep, wait);
417 
418 	avail = snd_compr_get_avail(stream);
419 	pr_debug("avail is %ld\n", (unsigned long)avail);
420 	/* check if we have at least one fragment to fill */
421 	switch (stream->runtime->state) {
422 	case SNDRV_PCM_STATE_DRAINING:
423 		/* stream has been woken up after drain is complete
424 		 * draining done so set stream state to stopped
425 		 */
426 		retval = snd_compr_get_poll(stream);
427 		stream->runtime->state = SNDRV_PCM_STATE_SETUP;
428 		break;
429 	case SNDRV_PCM_STATE_RUNNING:
430 	case SNDRV_PCM_STATE_PREPARED:
431 	case SNDRV_PCM_STATE_PAUSED:
432 		if (avail >= stream->runtime->fragment_size)
433 			retval = snd_compr_get_poll(stream);
434 		break;
435 	default:
436 		retval = snd_compr_get_poll(stream) | EPOLLERR;
437 		break;
438 	}
439 out:
440 	mutex_unlock(&stream->device->lock);
441 	return retval;
442 }
443 
444 static int
445 snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
446 {
447 	int retval;
448 	struct snd_compr_caps caps;
449 
450 	if (!stream->ops->get_caps)
451 		return -ENXIO;
452 
453 	memset(&caps, 0, sizeof(caps));
454 	retval = stream->ops->get_caps(stream, &caps);
455 	if (retval)
456 		goto out;
457 	if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
458 		retval = -EFAULT;
459 out:
460 	return retval;
461 }
462 
463 #ifndef COMPR_CODEC_CAPS_OVERFLOW
464 static int
465 snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
466 {
467 	int retval;
468 	struct snd_compr_codec_caps *caps;
469 
470 	if (!stream->ops->get_codec_caps)
471 		return -ENXIO;
472 
473 	caps = kzalloc(sizeof(*caps), GFP_KERNEL);
474 	if (!caps)
475 		return -ENOMEM;
476 
477 	retval = stream->ops->get_codec_caps(stream, caps);
478 	if (retval)
479 		goto out;
480 	if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
481 		retval = -EFAULT;
482 
483 out:
484 	kfree(caps);
485 	return retval;
486 }
487 #endif /* !COMPR_CODEC_CAPS_OVERFLOW */
488 
489 int snd_compr_malloc_pages(struct snd_compr_stream *stream, size_t size)
490 {
491 	struct snd_dma_buffer *dmab;
492 	int ret;
493 
494 	if (snd_BUG_ON(!(stream) || !(stream)->runtime))
495 		return -EINVAL;
496 	dmab = kzalloc(sizeof(*dmab), GFP_KERNEL);
497 	if (!dmab)
498 		return -ENOMEM;
499 	dmab->dev = stream->dma_buffer.dev;
500 	ret = snd_dma_alloc_pages(dmab->dev.type, dmab->dev.dev, size, dmab);
501 	if (ret < 0) {
502 		kfree(dmab);
503 		return ret;
504 	}
505 
506 	snd_compr_set_runtime_buffer(stream, dmab);
507 	stream->runtime->dma_bytes = size;
508 	return 1;
509 }
510 EXPORT_SYMBOL(snd_compr_malloc_pages);
511 
512 int snd_compr_free_pages(struct snd_compr_stream *stream)
513 {
514 	struct snd_compr_runtime *runtime;
515 
516 	if (snd_BUG_ON(!(stream) || !(stream)->runtime))
517 		return -EINVAL;
518 	runtime = stream->runtime;
519 	if (runtime->dma_area == NULL)
520 		return 0;
521 	if (runtime->dma_buffer_p != &stream->dma_buffer) {
522 		/* It's a newly allocated buffer. Release it now. */
523 		snd_dma_free_pages(runtime->dma_buffer_p);
524 		kfree(runtime->dma_buffer_p);
525 	}
526 
527 	snd_compr_set_runtime_buffer(stream, NULL);
528 	return 0;
529 }
530 EXPORT_SYMBOL(snd_compr_free_pages);
531 
532 /* revisit this with snd_pcm_preallocate_xxx */
533 static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
534 		struct snd_compr_params *params)
535 {
536 	unsigned int buffer_size;
537 	void *buffer = NULL;
538 
539 	buffer_size = params->buffer.fragment_size * params->buffer.fragments;
540 	if (stream->ops->copy) {
541 		buffer = NULL;
542 		/* if copy is defined the driver will be required to copy
543 		 * the data from core
544 		 */
545 	} else {
546 		if (stream->runtime->dma_buffer_p) {
547 
548 			if (buffer_size > stream->runtime->dma_buffer_p->bytes)
549 				dev_err(stream->device->dev,
550 						"Not enough DMA buffer");
551 			else
552 				buffer = stream->runtime->dma_buffer_p->area;
553 
554 		} else {
555 			buffer = kmalloc(buffer_size, GFP_KERNEL);
556 		}
557 
558 		if (!buffer)
559 			return -ENOMEM;
560 	}
561 	stream->runtime->fragment_size = params->buffer.fragment_size;
562 	stream->runtime->fragments = params->buffer.fragments;
563 	stream->runtime->buffer = buffer;
564 	stream->runtime->buffer_size = buffer_size;
565 	return 0;
566 }
567 
568 static int snd_compress_check_input(struct snd_compr_params *params)
569 {
570 	/* first let's check the buffer parameter's */
571 	if (params->buffer.fragment_size == 0 ||
572 	    params->buffer.fragments > U32_MAX / params->buffer.fragment_size ||
573 	    params->buffer.fragments == 0)
574 		return -EINVAL;
575 
576 	/* now codec parameters */
577 	if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
578 		return -EINVAL;
579 
580 	if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
581 		return -EINVAL;
582 
583 	return 0;
584 }
585 
586 static int
587 snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
588 {
589 	struct snd_compr_params *params;
590 	int retval;
591 
592 	if (stream->runtime->state == SNDRV_PCM_STATE_OPEN || stream->next_track) {
593 		/*
594 		 * we should allow parameter change only when stream has been
595 		 * opened not in other cases
596 		 */
597 		params = memdup_user((void __user *)arg, sizeof(*params));
598 		if (IS_ERR(params))
599 			return PTR_ERR(params);
600 
601 		retval = snd_compress_check_input(params);
602 		if (retval)
603 			goto out;
604 
605 		retval = snd_compr_allocate_buffer(stream, params);
606 		if (retval) {
607 			retval = -ENOMEM;
608 			goto out;
609 		}
610 
611 		retval = stream->ops->set_params(stream, params);
612 		if (retval)
613 			goto out;
614 
615 		if (stream->next_track)
616 			goto out;
617 
618 		stream->metadata_set = false;
619 		stream->next_track = false;
620 
621 		stream->runtime->state = SNDRV_PCM_STATE_SETUP;
622 	} else {
623 		return -EPERM;
624 	}
625 out:
626 	kfree(params);
627 	return retval;
628 }
629 
630 static int
631 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
632 {
633 	struct snd_codec *params;
634 	int retval;
635 
636 	if (!stream->ops->get_params)
637 		return -EBADFD;
638 
639 	params = kzalloc(sizeof(*params), GFP_KERNEL);
640 	if (!params)
641 		return -ENOMEM;
642 	retval = stream->ops->get_params(stream, params);
643 	if (retval)
644 		goto out;
645 	if (copy_to_user((char __user *)arg, params, sizeof(*params)))
646 		retval = -EFAULT;
647 
648 out:
649 	kfree(params);
650 	return retval;
651 }
652 
653 static int
654 snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
655 {
656 	struct snd_compr_metadata metadata;
657 	int retval;
658 
659 	if (!stream->ops->get_metadata)
660 		return -ENXIO;
661 
662 	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
663 		return -EFAULT;
664 
665 	retval = stream->ops->get_metadata(stream, &metadata);
666 	if (retval != 0)
667 		return retval;
668 
669 	if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
670 		return -EFAULT;
671 
672 	return 0;
673 }
674 
675 static int
676 snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
677 {
678 	struct snd_compr_metadata metadata;
679 	int retval;
680 
681 	if (!stream->ops->set_metadata)
682 		return -ENXIO;
683 	/*
684 	* we should allow parameter change only when stream has been
685 	* opened not in other cases
686 	*/
687 	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
688 		return -EFAULT;
689 
690 	retval = stream->ops->set_metadata(stream, &metadata);
691 	stream->metadata_set = true;
692 
693 	return retval;
694 }
695 
696 static inline int
697 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
698 {
699 	struct snd_compr_tstamp tstamp = {0};
700 	int ret;
701 
702 	ret = snd_compr_update_tstamp(stream, &tstamp);
703 	if (ret == 0)
704 		ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
705 			&tstamp, sizeof(tstamp)) ? -EFAULT : 0;
706 	return ret;
707 }
708 
709 static int snd_compr_pause(struct snd_compr_stream *stream)
710 {
711 	int retval;
712 
713 	switch (stream->runtime->state) {
714 	case SNDRV_PCM_STATE_RUNNING:
715 		retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
716 		if (!retval)
717 			stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
718 		break;
719 	case SNDRV_PCM_STATE_DRAINING:
720 		if (!stream->device->use_pause_in_draining)
721 			return -EPERM;
722 		retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
723 		if (!retval)
724 			stream->pause_in_draining = true;
725 		break;
726 	default:
727 		return -EPERM;
728 	}
729 	return retval;
730 }
731 
732 static int snd_compr_resume(struct snd_compr_stream *stream)
733 {
734 	int retval;
735 
736 	switch (stream->runtime->state) {
737 	case SNDRV_PCM_STATE_PAUSED:
738 		retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
739 		if (!retval)
740 			stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
741 		break;
742 	case SNDRV_PCM_STATE_DRAINING:
743 		if (!stream->pause_in_draining)
744 			return -EPERM;
745 		retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
746 		if (!retval)
747 			stream->pause_in_draining = false;
748 		break;
749 	default:
750 		return -EPERM;
751 	}
752 	return retval;
753 }
754 
755 static int snd_compr_start(struct snd_compr_stream *stream)
756 {
757 	int retval;
758 
759 	switch (stream->runtime->state) {
760 	case SNDRV_PCM_STATE_SETUP:
761 		if (stream->direction != SND_COMPRESS_CAPTURE)
762 			return -EPERM;
763 		break;
764 	case SNDRV_PCM_STATE_PREPARED:
765 		break;
766 	default:
767 		return -EPERM;
768 	}
769 
770 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
771 	if (!retval)
772 		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
773 	return retval;
774 }
775 
776 static int snd_compr_stop(struct snd_compr_stream *stream)
777 {
778 	int retval;
779 
780 	switch (stream->runtime->state) {
781 	case SNDRV_PCM_STATE_OPEN:
782 	case SNDRV_PCM_STATE_SETUP:
783 	case SNDRV_PCM_STATE_PREPARED:
784 		return -EPERM;
785 	default:
786 		break;
787 	}
788 
789 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
790 	if (!retval) {
791 		/* clear flags and stop any drain wait */
792 		stream->partial_drain = false;
793 		stream->metadata_set = false;
794 		stream->pause_in_draining = false;
795 		snd_compr_drain_notify(stream);
796 		stream->runtime->total_bytes_available = 0;
797 		stream->runtime->total_bytes_transferred = 0;
798 	}
799 	return retval;
800 }
801 
802 static void error_delayed_work(struct work_struct *work)
803 {
804 	struct snd_compr_stream *stream;
805 
806 	stream = container_of(work, struct snd_compr_stream, error_work.work);
807 
808 	mutex_lock(&stream->device->lock);
809 
810 	stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
811 	wake_up(&stream->runtime->sleep);
812 
813 	mutex_unlock(&stream->device->lock);
814 }
815 
816 /**
817  * snd_compr_stop_error: Report a fatal error on a stream
818  * @stream: pointer to stream
819  * @state: state to transition the stream to
820  *
821  * Stop the stream and set its state.
822  *
823  * Should be called with compressed device lock held.
824  *
825  * Return: zero if successful, or a negative error code
826  */
827 int snd_compr_stop_error(struct snd_compr_stream *stream,
828 			 snd_pcm_state_t state)
829 {
830 	if (stream->runtime->state == state)
831 		return 0;
832 
833 	stream->runtime->state = state;
834 
835 	pr_debug("Changing state to: %d\n", state);
836 
837 	queue_delayed_work(system_power_efficient_wq, &stream->error_work, 0);
838 
839 	return 0;
840 }
841 EXPORT_SYMBOL_GPL(snd_compr_stop_error);
842 
843 static int snd_compress_wait_for_drain(struct snd_compr_stream *stream)
844 {
845 	int ret;
846 
847 	/*
848 	 * We are called with lock held. So drop the lock while we wait for
849 	 * drain complete notification from the driver
850 	 *
851 	 * It is expected that driver will notify the drain completion and then
852 	 * stream will be moved to SETUP state, even if draining resulted in an
853 	 * error. We can trigger next track after this.
854 	 */
855 	stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
856 	mutex_unlock(&stream->device->lock);
857 
858 	/* we wait for drain to complete here, drain can return when
859 	 * interruption occurred, wait returned error or success.
860 	 * For the first two cases we don't do anything different here and
861 	 * return after waking up
862 	 */
863 
864 	ret = wait_event_interruptible(stream->runtime->sleep,
865 			(stream->runtime->state != SNDRV_PCM_STATE_DRAINING));
866 	if (ret == -ERESTARTSYS)
867 		pr_debug("wait aborted by a signal\n");
868 	else if (ret)
869 		pr_debug("wait for drain failed with %d\n", ret);
870 
871 
872 	wake_up(&stream->runtime->sleep);
873 	mutex_lock(&stream->device->lock);
874 
875 	return ret;
876 }
877 
878 static int snd_compr_drain(struct snd_compr_stream *stream)
879 {
880 	int retval;
881 
882 	switch (stream->runtime->state) {
883 	case SNDRV_PCM_STATE_OPEN:
884 	case SNDRV_PCM_STATE_SETUP:
885 	case SNDRV_PCM_STATE_PREPARED:
886 	case SNDRV_PCM_STATE_PAUSED:
887 		return -EPERM;
888 	case SNDRV_PCM_STATE_XRUN:
889 		return -EPIPE;
890 	default:
891 		break;
892 	}
893 
894 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
895 	if (retval) {
896 		pr_debug("SND_COMPR_TRIGGER_DRAIN failed %d\n", retval);
897 		wake_up(&stream->runtime->sleep);
898 		return retval;
899 	}
900 
901 	return snd_compress_wait_for_drain(stream);
902 }
903 
904 static int snd_compr_next_track(struct snd_compr_stream *stream)
905 {
906 	int retval;
907 
908 	/* only a running stream can transition to next track */
909 	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
910 		return -EPERM;
911 
912 	/* next track doesn't have any meaning for capture streams */
913 	if (stream->direction == SND_COMPRESS_CAPTURE)
914 		return -EPERM;
915 
916 	/* you can signal next track if this is intended to be a gapless stream
917 	 * and current track metadata is set
918 	 */
919 	if (stream->metadata_set == false)
920 		return -EPERM;
921 
922 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
923 	if (retval != 0)
924 		return retval;
925 	stream->metadata_set = false;
926 	stream->next_track = true;
927 	return 0;
928 }
929 
930 static int snd_compr_partial_drain(struct snd_compr_stream *stream)
931 {
932 	int retval;
933 
934 	switch (stream->runtime->state) {
935 	case SNDRV_PCM_STATE_OPEN:
936 	case SNDRV_PCM_STATE_SETUP:
937 	case SNDRV_PCM_STATE_PREPARED:
938 	case SNDRV_PCM_STATE_PAUSED:
939 		return -EPERM;
940 	case SNDRV_PCM_STATE_XRUN:
941 		return -EPIPE;
942 	default:
943 		break;
944 	}
945 
946 	/* partial drain doesn't have any meaning for capture streams */
947 	if (stream->direction == SND_COMPRESS_CAPTURE)
948 		return -EPERM;
949 
950 	/* stream can be drained only when next track has been signalled */
951 	if (stream->next_track == false)
952 		return -EPERM;
953 
954 	stream->partial_drain = true;
955 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
956 	if (retval) {
957 		pr_debug("Partial drain returned failure\n");
958 		wake_up(&stream->runtime->sleep);
959 		return retval;
960 	}
961 
962 	stream->next_track = false;
963 	return snd_compress_wait_for_drain(stream);
964 }
965 
966 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
967 {
968 	struct snd_compr_file *data = f->private_data;
969 	struct snd_compr_stream *stream;
970 	int retval = -ENOTTY;
971 
972 	if (snd_BUG_ON(!data))
973 		return -EFAULT;
974 
975 	stream = &data->stream;
976 
977 	mutex_lock(&stream->device->lock);
978 	switch (_IOC_NR(cmd)) {
979 	case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
980 		retval = put_user(SNDRV_COMPRESS_VERSION,
981 				(int __user *)arg) ? -EFAULT : 0;
982 		break;
983 	case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
984 		retval = snd_compr_get_caps(stream, arg);
985 		break;
986 #ifndef COMPR_CODEC_CAPS_OVERFLOW
987 	case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
988 		retval = snd_compr_get_codec_caps(stream, arg);
989 		break;
990 #endif
991 	case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
992 		retval = snd_compr_set_params(stream, arg);
993 		break;
994 	case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
995 		retval = snd_compr_get_params(stream, arg);
996 		break;
997 	case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
998 		retval = snd_compr_set_metadata(stream, arg);
999 		break;
1000 	case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
1001 		retval = snd_compr_get_metadata(stream, arg);
1002 		break;
1003 	case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
1004 		retval = snd_compr_tstamp(stream, arg);
1005 		break;
1006 	case _IOC_NR(SNDRV_COMPRESS_AVAIL):
1007 		retval = snd_compr_ioctl_avail(stream, arg);
1008 		break;
1009 	case _IOC_NR(SNDRV_COMPRESS_PAUSE):
1010 		retval = snd_compr_pause(stream);
1011 		break;
1012 	case _IOC_NR(SNDRV_COMPRESS_RESUME):
1013 		retval = snd_compr_resume(stream);
1014 		break;
1015 	case _IOC_NR(SNDRV_COMPRESS_START):
1016 		retval = snd_compr_start(stream);
1017 		break;
1018 	case _IOC_NR(SNDRV_COMPRESS_STOP):
1019 		retval = snd_compr_stop(stream);
1020 		break;
1021 	case _IOC_NR(SNDRV_COMPRESS_DRAIN):
1022 		retval = snd_compr_drain(stream);
1023 		break;
1024 	case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
1025 		retval = snd_compr_partial_drain(stream);
1026 		break;
1027 	case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
1028 		retval = snd_compr_next_track(stream);
1029 		break;
1030 
1031 	}
1032 	mutex_unlock(&stream->device->lock);
1033 	return retval;
1034 }
1035 
1036 /* support of 32bit userspace on 64bit platforms */
1037 #ifdef CONFIG_COMPAT
1038 static long snd_compr_ioctl_compat(struct file *file, unsigned int cmd,
1039 						unsigned long arg)
1040 {
1041 	return snd_compr_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
1042 }
1043 #endif
1044 
1045 static const struct file_operations snd_compr_file_ops = {
1046 		.owner =	THIS_MODULE,
1047 		.open =		snd_compr_open,
1048 		.release =	snd_compr_free,
1049 		.write =	snd_compr_write,
1050 		.read =		snd_compr_read,
1051 		.unlocked_ioctl = snd_compr_ioctl,
1052 #ifdef CONFIG_COMPAT
1053 		.compat_ioctl = snd_compr_ioctl_compat,
1054 #endif
1055 		.mmap =		snd_compr_mmap,
1056 		.poll =		snd_compr_poll,
1057 };
1058 
1059 static int snd_compress_dev_register(struct snd_device *device)
1060 {
1061 	int ret;
1062 	struct snd_compr *compr;
1063 
1064 	if (snd_BUG_ON(!device || !device->device_data))
1065 		return -EBADFD;
1066 	compr = device->device_data;
1067 
1068 	pr_debug("reg device %s, direction %d\n", compr->name,
1069 			compr->direction);
1070 	/* register compressed device */
1071 	ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS,
1072 				  compr->card, compr->device,
1073 				  &snd_compr_file_ops, compr, compr->dev);
1074 	if (ret < 0) {
1075 		pr_err("snd_register_device failed %d\n", ret);
1076 		return ret;
1077 	}
1078 	return ret;
1079 
1080 }
1081 
1082 static int snd_compress_dev_disconnect(struct snd_device *device)
1083 {
1084 	struct snd_compr *compr;
1085 
1086 	compr = device->device_data;
1087 	snd_unregister_device(compr->dev);
1088 	return 0;
1089 }
1090 
1091 #ifdef CONFIG_SND_VERBOSE_PROCFS
1092 static void snd_compress_proc_info_read(struct snd_info_entry *entry,
1093 					struct snd_info_buffer *buffer)
1094 {
1095 	struct snd_compr *compr = (struct snd_compr *)entry->private_data;
1096 
1097 	snd_iprintf(buffer, "card: %d\n", compr->card->number);
1098 	snd_iprintf(buffer, "device: %d\n", compr->device);
1099 	snd_iprintf(buffer, "stream: %s\n",
1100 			compr->direction == SND_COMPRESS_PLAYBACK
1101 				? "PLAYBACK" : "CAPTURE");
1102 	snd_iprintf(buffer, "id: %s\n", compr->id);
1103 }
1104 
1105 static int snd_compress_proc_init(struct snd_compr *compr)
1106 {
1107 	struct snd_info_entry *entry;
1108 	char name[16];
1109 
1110 	sprintf(name, "compr%i", compr->device);
1111 	entry = snd_info_create_card_entry(compr->card, name,
1112 					   compr->card->proc_root);
1113 	if (!entry)
1114 		return -ENOMEM;
1115 	entry->mode = S_IFDIR | 0555;
1116 	compr->proc_root = entry;
1117 
1118 	entry = snd_info_create_card_entry(compr->card, "info",
1119 					   compr->proc_root);
1120 	if (entry)
1121 		snd_info_set_text_ops(entry, compr,
1122 				      snd_compress_proc_info_read);
1123 	compr->proc_info_entry = entry;
1124 
1125 	return 0;
1126 }
1127 
1128 static void snd_compress_proc_done(struct snd_compr *compr)
1129 {
1130 	snd_info_free_entry(compr->proc_info_entry);
1131 	compr->proc_info_entry = NULL;
1132 	snd_info_free_entry(compr->proc_root);
1133 	compr->proc_root = NULL;
1134 }
1135 
1136 static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
1137 {
1138 	strscpy(compr->id, id, sizeof(compr->id));
1139 }
1140 #else
1141 static inline int snd_compress_proc_init(struct snd_compr *compr)
1142 {
1143 	return 0;
1144 }
1145 
1146 static inline void snd_compress_proc_done(struct snd_compr *compr)
1147 {
1148 }
1149 
1150 static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
1151 {
1152 }
1153 #endif
1154 
1155 static int snd_compress_dev_free(struct snd_device *device)
1156 {
1157 	struct snd_compr *compr;
1158 
1159 	compr = device->device_data;
1160 	snd_compress_proc_done(compr);
1161 	put_device(compr->dev);
1162 	return 0;
1163 }
1164 
1165 /**
1166  * snd_compress_new: create new compress device
1167  * @card: sound card pointer
1168  * @device: device number
1169  * @dirn: device direction, should be of type enum snd_compr_direction
1170  * @id: ID string
1171  * @compr: compress device pointer
1172  *
1173  * Return: zero if successful, or a negative error code
1174  */
1175 int snd_compress_new(struct snd_card *card, int device,
1176 			int dirn, const char *id, struct snd_compr *compr)
1177 {
1178 	static const struct snd_device_ops ops = {
1179 		.dev_free = snd_compress_dev_free,
1180 		.dev_register = snd_compress_dev_register,
1181 		.dev_disconnect = snd_compress_dev_disconnect,
1182 	};
1183 	int ret;
1184 
1185 	compr->card = card;
1186 	compr->device = device;
1187 	compr->direction = dirn;
1188 	mutex_init(&compr->lock);
1189 
1190 	snd_compress_set_id(compr, id);
1191 
1192 	ret = snd_device_alloc(&compr->dev, card);
1193 	if (ret)
1194 		return ret;
1195 	dev_set_name(compr->dev, "comprC%iD%i", card->number, device);
1196 
1197 	ret = snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
1198 	if (ret == 0)
1199 		snd_compress_proc_init(compr);
1200 	else
1201 		put_device(compr->dev);
1202 
1203 	return ret;
1204 }
1205 EXPORT_SYMBOL_GPL(snd_compress_new);
1206 
1207 MODULE_DESCRIPTION("ALSA Compressed offload framework");
1208 MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
1209 MODULE_LICENSE("GPL v2");
1210