xref: /openbmc/linux/sound/core/compress_offload.c (revision 2596e07a)
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 /*
71  * a note on stream states used:
72  * we use follwing states in the compressed core
73  * SNDRV_PCM_STATE_OPEN: When stream has been opened.
74  * SNDRV_PCM_STATE_SETUP: When stream has been initialized. This is done by
75  *	calling SNDRV_COMPRESS_SET_PARAMS. running streams will come to this
76  *	state at stop by calling SNDRV_COMPRESS_STOP, or at end of drain.
77  * SNDRV_PCM_STATE_RUNNING: When stream has been started and is
78  *	decoding/encoding and rendering/capturing data.
79  * SNDRV_PCM_STATE_DRAINING: When stream is draining current data. This is done
80  *	by calling SNDRV_COMPRESS_DRAIN.
81  * SNDRV_PCM_STATE_PAUSED: When stream is paused. This is done by calling
82  *	SNDRV_COMPRESS_PAUSE. It can be stopped or resumed by calling
83  *	SNDRV_COMPRESS_STOP or SNDRV_COMPRESS_RESUME respectively.
84  */
85 static int snd_compr_open(struct inode *inode, struct file *f)
86 {
87 	struct snd_compr *compr;
88 	struct snd_compr_file *data;
89 	struct snd_compr_runtime *runtime;
90 	enum snd_compr_direction dirn;
91 	int maj = imajor(inode);
92 	int ret;
93 
94 	if ((f->f_flags & O_ACCMODE) == O_WRONLY)
95 		dirn = SND_COMPRESS_PLAYBACK;
96 	else if ((f->f_flags & O_ACCMODE) == O_RDONLY)
97 		dirn = SND_COMPRESS_CAPTURE;
98 	else
99 		return -EINVAL;
100 
101 	if (maj == snd_major)
102 		compr = snd_lookup_minor_data(iminor(inode),
103 					SNDRV_DEVICE_TYPE_COMPRESS);
104 	else
105 		return -EBADFD;
106 
107 	if (compr == NULL) {
108 		pr_err("no device data!!!\n");
109 		return -ENODEV;
110 	}
111 
112 	if (dirn != compr->direction) {
113 		pr_err("this device doesn't support this direction\n");
114 		snd_card_unref(compr->card);
115 		return -EINVAL;
116 	}
117 
118 	data = kzalloc(sizeof(*data), GFP_KERNEL);
119 	if (!data) {
120 		snd_card_unref(compr->card);
121 		return -ENOMEM;
122 	}
123 	data->stream.ops = compr->ops;
124 	data->stream.direction = dirn;
125 	data->stream.private_data = compr->private_data;
126 	data->stream.device = compr;
127 	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
128 	if (!runtime) {
129 		kfree(data);
130 		snd_card_unref(compr->card);
131 		return -ENOMEM;
132 	}
133 	runtime->state = SNDRV_PCM_STATE_OPEN;
134 	init_waitqueue_head(&runtime->sleep);
135 	data->stream.runtime = runtime;
136 	f->private_data = (void *)data;
137 	mutex_lock(&compr->lock);
138 	ret = compr->ops->open(&data->stream);
139 	mutex_unlock(&compr->lock);
140 	if (ret) {
141 		kfree(runtime);
142 		kfree(data);
143 	}
144 	snd_card_unref(compr->card);
145 	return ret;
146 }
147 
148 static int snd_compr_free(struct inode *inode, struct file *f)
149 {
150 	struct snd_compr_file *data = f->private_data;
151 	struct snd_compr_runtime *runtime = data->stream.runtime;
152 
153 	switch (runtime->state) {
154 	case SNDRV_PCM_STATE_RUNNING:
155 	case SNDRV_PCM_STATE_DRAINING:
156 	case SNDRV_PCM_STATE_PAUSED:
157 		data->stream.ops->trigger(&data->stream, SNDRV_PCM_TRIGGER_STOP);
158 		break;
159 	default:
160 		break;
161 	}
162 
163 	data->stream.ops->free(&data->stream);
164 	kfree(data->stream.runtime->buffer);
165 	kfree(data->stream.runtime);
166 	kfree(data);
167 	return 0;
168 }
169 
170 static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
171 		struct snd_compr_tstamp *tstamp)
172 {
173 	if (!stream->ops->pointer)
174 		return -ENOTSUPP;
175 	stream->ops->pointer(stream, tstamp);
176 	pr_debug("dsp consumed till %d total %d bytes\n",
177 		tstamp->byte_offset, tstamp->copied_total);
178 	if (stream->direction == SND_COMPRESS_PLAYBACK)
179 		stream->runtime->total_bytes_transferred = tstamp->copied_total;
180 	else
181 		stream->runtime->total_bytes_available = tstamp->copied_total;
182 	return 0;
183 }
184 
185 static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
186 		struct snd_compr_avail *avail)
187 {
188 	memset(avail, 0, sizeof(*avail));
189 	snd_compr_update_tstamp(stream, &avail->tstamp);
190 	/* Still need to return avail even if tstamp can't be filled in */
191 
192 	if (stream->runtime->total_bytes_available == 0 &&
193 			stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
194 			stream->direction == SND_COMPRESS_PLAYBACK) {
195 		pr_debug("detected init and someone forgot to do a write\n");
196 		return stream->runtime->buffer_size;
197 	}
198 	pr_debug("app wrote %lld, DSP consumed %lld\n",
199 			stream->runtime->total_bytes_available,
200 			stream->runtime->total_bytes_transferred);
201 	if (stream->runtime->total_bytes_available ==
202 				stream->runtime->total_bytes_transferred) {
203 		if (stream->direction == SND_COMPRESS_PLAYBACK) {
204 			pr_debug("both pointers are same, returning full avail\n");
205 			return stream->runtime->buffer_size;
206 		} else {
207 			pr_debug("both pointers are same, returning no avail\n");
208 			return 0;
209 		}
210 	}
211 
212 	avail->avail = stream->runtime->total_bytes_available -
213 			stream->runtime->total_bytes_transferred;
214 	if (stream->direction == SND_COMPRESS_PLAYBACK)
215 		avail->avail = stream->runtime->buffer_size - avail->avail;
216 
217 	pr_debug("ret avail as %lld\n", avail->avail);
218 	return avail->avail;
219 }
220 
221 static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
222 {
223 	struct snd_compr_avail avail;
224 
225 	return snd_compr_calc_avail(stream, &avail);
226 }
227 
228 static int
229 snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
230 {
231 	struct snd_compr_avail ioctl_avail;
232 	size_t avail;
233 
234 	avail = snd_compr_calc_avail(stream, &ioctl_avail);
235 	ioctl_avail.avail = avail;
236 
237 	if (copy_to_user((__u64 __user *)arg,
238 				&ioctl_avail, sizeof(ioctl_avail)))
239 		return -EFAULT;
240 	return 0;
241 }
242 
243 static int snd_compr_write_data(struct snd_compr_stream *stream,
244 	       const char __user *buf, size_t count)
245 {
246 	void *dstn;
247 	size_t copy;
248 	struct snd_compr_runtime *runtime = stream->runtime;
249 	/* 64-bit Modulus */
250 	u64 app_pointer = div64_u64(runtime->total_bytes_available,
251 				    runtime->buffer_size);
252 	app_pointer = runtime->total_bytes_available -
253 		      (app_pointer * runtime->buffer_size);
254 
255 	dstn = runtime->buffer + app_pointer;
256 	pr_debug("copying %ld at %lld\n",
257 			(unsigned long)count, app_pointer);
258 	if (count < runtime->buffer_size - app_pointer) {
259 		if (copy_from_user(dstn, buf, count))
260 			return -EFAULT;
261 	} else {
262 		copy = runtime->buffer_size - app_pointer;
263 		if (copy_from_user(dstn, buf, copy))
264 			return -EFAULT;
265 		if (copy_from_user(runtime->buffer, buf + copy, count - copy))
266 			return -EFAULT;
267 	}
268 	/* if DSP cares, let it know data has been written */
269 	if (stream->ops->ack)
270 		stream->ops->ack(stream, count);
271 	return count;
272 }
273 
274 static ssize_t snd_compr_write(struct file *f, const char __user *buf,
275 		size_t count, loff_t *offset)
276 {
277 	struct snd_compr_file *data = f->private_data;
278 	struct snd_compr_stream *stream;
279 	size_t avail;
280 	int retval;
281 
282 	if (snd_BUG_ON(!data))
283 		return -EFAULT;
284 
285 	stream = &data->stream;
286 	mutex_lock(&stream->device->lock);
287 	/* write is allowed when stream is running or has been steup */
288 	if (stream->runtime->state != SNDRV_PCM_STATE_SETUP &&
289 			stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
290 		mutex_unlock(&stream->device->lock);
291 		return -EBADFD;
292 	}
293 
294 	avail = snd_compr_get_avail(stream);
295 	pr_debug("avail returned %ld\n", (unsigned long)avail);
296 	/* calculate how much we can write to buffer */
297 	if (avail > count)
298 		avail = count;
299 
300 	if (stream->ops->copy) {
301 		char __user* cbuf = (char __user*)buf;
302 		retval = stream->ops->copy(stream, cbuf, avail);
303 	} else {
304 		retval = snd_compr_write_data(stream, buf, avail);
305 	}
306 	if (retval > 0)
307 		stream->runtime->total_bytes_available += retval;
308 
309 	/* while initiating the stream, write should be called before START
310 	 * call, so in setup move state */
311 	if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
312 		stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
313 		pr_debug("stream prepared, Houston we are good to go\n");
314 	}
315 
316 	mutex_unlock(&stream->device->lock);
317 	return retval;
318 }
319 
320 
321 static ssize_t snd_compr_read(struct file *f, char __user *buf,
322 		size_t count, loff_t *offset)
323 {
324 	struct snd_compr_file *data = f->private_data;
325 	struct snd_compr_stream *stream;
326 	size_t avail;
327 	int retval;
328 
329 	if (snd_BUG_ON(!data))
330 		return -EFAULT;
331 
332 	stream = &data->stream;
333 	mutex_lock(&stream->device->lock);
334 
335 	/* read is allowed when stream is running, paused, draining and setup
336 	 * (yes setup is state which we transition to after stop, so if user
337 	 * wants to read data after stop we allow that)
338 	 */
339 	switch (stream->runtime->state) {
340 	case SNDRV_PCM_STATE_OPEN:
341 	case SNDRV_PCM_STATE_PREPARED:
342 	case SNDRV_PCM_STATE_XRUN:
343 	case SNDRV_PCM_STATE_SUSPENDED:
344 	case SNDRV_PCM_STATE_DISCONNECTED:
345 		retval = -EBADFD;
346 		goto out;
347 	}
348 
349 	avail = snd_compr_get_avail(stream);
350 	pr_debug("avail returned %ld\n", (unsigned long)avail);
351 	/* calculate how much we can read from buffer */
352 	if (avail > count)
353 		avail = count;
354 
355 	if (stream->ops->copy) {
356 		retval = stream->ops->copy(stream, buf, avail);
357 	} else {
358 		retval = -ENXIO;
359 		goto out;
360 	}
361 	if (retval > 0)
362 		stream->runtime->total_bytes_transferred += retval;
363 
364 out:
365 	mutex_unlock(&stream->device->lock);
366 	return retval;
367 }
368 
369 static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
370 {
371 	return -ENXIO;
372 }
373 
374 static inline int snd_compr_get_poll(struct snd_compr_stream *stream)
375 {
376 	if (stream->direction == SND_COMPRESS_PLAYBACK)
377 		return POLLOUT | POLLWRNORM;
378 	else
379 		return POLLIN | POLLRDNORM;
380 }
381 
382 static unsigned int snd_compr_poll(struct file *f, poll_table *wait)
383 {
384 	struct snd_compr_file *data = f->private_data;
385 	struct snd_compr_stream *stream;
386 	size_t avail;
387 	int retval = 0;
388 
389 	if (snd_BUG_ON(!data))
390 		return -EFAULT;
391 	stream = &data->stream;
392 	if (snd_BUG_ON(!stream))
393 		return -EFAULT;
394 
395 	mutex_lock(&stream->device->lock);
396 	if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
397 		retval = -EBADFD;
398 		goto out;
399 	}
400 	poll_wait(f, &stream->runtime->sleep, wait);
401 
402 	avail = snd_compr_get_avail(stream);
403 	pr_debug("avail is %ld\n", (unsigned long)avail);
404 	/* check if we have at least one fragment to fill */
405 	switch (stream->runtime->state) {
406 	case SNDRV_PCM_STATE_DRAINING:
407 		/* stream has been woken up after drain is complete
408 		 * draining done so set stream state to stopped
409 		 */
410 		retval = snd_compr_get_poll(stream);
411 		stream->runtime->state = SNDRV_PCM_STATE_SETUP;
412 		break;
413 	case SNDRV_PCM_STATE_RUNNING:
414 	case SNDRV_PCM_STATE_PREPARED:
415 	case SNDRV_PCM_STATE_PAUSED:
416 		if (avail >= stream->runtime->fragment_size)
417 			retval = snd_compr_get_poll(stream);
418 		break;
419 	default:
420 		if (stream->direction == SND_COMPRESS_PLAYBACK)
421 			retval = POLLOUT | POLLWRNORM | POLLERR;
422 		else
423 			retval = POLLIN | POLLRDNORM | POLLERR;
424 		break;
425 	}
426 out:
427 	mutex_unlock(&stream->device->lock);
428 	return retval;
429 }
430 
431 static int
432 snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
433 {
434 	int retval;
435 	struct snd_compr_caps caps;
436 
437 	if (!stream->ops->get_caps)
438 		return -ENXIO;
439 
440 	memset(&caps, 0, sizeof(caps));
441 	retval = stream->ops->get_caps(stream, &caps);
442 	if (retval)
443 		goto out;
444 	if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
445 		retval = -EFAULT;
446 out:
447 	return retval;
448 }
449 
450 #ifndef COMPR_CODEC_CAPS_OVERFLOW
451 static int
452 snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
453 {
454 	int retval;
455 	struct snd_compr_codec_caps *caps;
456 
457 	if (!stream->ops->get_codec_caps)
458 		return -ENXIO;
459 
460 	caps = kzalloc(sizeof(*caps), GFP_KERNEL);
461 	if (!caps)
462 		return -ENOMEM;
463 
464 	retval = stream->ops->get_codec_caps(stream, caps);
465 	if (retval)
466 		goto out;
467 	if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
468 		retval = -EFAULT;
469 
470 out:
471 	kfree(caps);
472 	return retval;
473 }
474 #endif /* !COMPR_CODEC_CAPS_OVERFLOW */
475 
476 /* revisit this with snd_pcm_preallocate_xxx */
477 static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
478 		struct snd_compr_params *params)
479 {
480 	unsigned int buffer_size;
481 	void *buffer;
482 
483 	buffer_size = params->buffer.fragment_size * params->buffer.fragments;
484 	if (stream->ops->copy) {
485 		buffer = NULL;
486 		/* if copy is defined the driver will be required to copy
487 		 * the data from core
488 		 */
489 	} else {
490 		buffer = kmalloc(buffer_size, GFP_KERNEL);
491 		if (!buffer)
492 			return -ENOMEM;
493 	}
494 	stream->runtime->fragment_size = params->buffer.fragment_size;
495 	stream->runtime->fragments = params->buffer.fragments;
496 	stream->runtime->buffer = buffer;
497 	stream->runtime->buffer_size = buffer_size;
498 	return 0;
499 }
500 
501 static int snd_compress_check_input(struct snd_compr_params *params)
502 {
503 	/* first let's check the buffer parameter's */
504 	if (params->buffer.fragment_size == 0 ||
505 	    params->buffer.fragments > INT_MAX / params->buffer.fragment_size)
506 		return -EINVAL;
507 
508 	/* now codec parameters */
509 	if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
510 		return -EINVAL;
511 
512 	if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
513 		return -EINVAL;
514 
515 	return 0;
516 }
517 
518 static int
519 snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
520 {
521 	struct snd_compr_params *params;
522 	int retval;
523 
524 	if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
525 		/*
526 		 * we should allow parameter change only when stream has been
527 		 * opened not in other cases
528 		 */
529 		params = kmalloc(sizeof(*params), GFP_KERNEL);
530 		if (!params)
531 			return -ENOMEM;
532 		if (copy_from_user(params, (void __user *)arg, sizeof(*params))) {
533 			retval = -EFAULT;
534 			goto out;
535 		}
536 
537 		retval = snd_compress_check_input(params);
538 		if (retval)
539 			goto out;
540 
541 		retval = snd_compr_allocate_buffer(stream, params);
542 		if (retval) {
543 			retval = -ENOMEM;
544 			goto out;
545 		}
546 
547 		retval = stream->ops->set_params(stream, params);
548 		if (retval)
549 			goto out;
550 
551 		stream->metadata_set = false;
552 		stream->next_track = false;
553 
554 		if (stream->direction == SND_COMPRESS_PLAYBACK)
555 			stream->runtime->state = SNDRV_PCM_STATE_SETUP;
556 		else
557 			stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
558 	} else {
559 		return -EPERM;
560 	}
561 out:
562 	kfree(params);
563 	return retval;
564 }
565 
566 static int
567 snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
568 {
569 	struct snd_codec *params;
570 	int retval;
571 
572 	if (!stream->ops->get_params)
573 		return -EBADFD;
574 
575 	params = kzalloc(sizeof(*params), GFP_KERNEL);
576 	if (!params)
577 		return -ENOMEM;
578 	retval = stream->ops->get_params(stream, params);
579 	if (retval)
580 		goto out;
581 	if (copy_to_user((char __user *)arg, params, sizeof(*params)))
582 		retval = -EFAULT;
583 
584 out:
585 	kfree(params);
586 	return retval;
587 }
588 
589 static int
590 snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
591 {
592 	struct snd_compr_metadata metadata;
593 	int retval;
594 
595 	if (!stream->ops->get_metadata)
596 		return -ENXIO;
597 
598 	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
599 		return -EFAULT;
600 
601 	retval = stream->ops->get_metadata(stream, &metadata);
602 	if (retval != 0)
603 		return retval;
604 
605 	if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
606 		return -EFAULT;
607 
608 	return 0;
609 }
610 
611 static int
612 snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
613 {
614 	struct snd_compr_metadata metadata;
615 	int retval;
616 
617 	if (!stream->ops->set_metadata)
618 		return -ENXIO;
619 	/*
620 	* we should allow parameter change only when stream has been
621 	* opened not in other cases
622 	*/
623 	if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
624 		return -EFAULT;
625 
626 	retval = stream->ops->set_metadata(stream, &metadata);
627 	stream->metadata_set = true;
628 
629 	return retval;
630 }
631 
632 static inline int
633 snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
634 {
635 	struct snd_compr_tstamp tstamp = {0};
636 	int ret;
637 
638 	ret = snd_compr_update_tstamp(stream, &tstamp);
639 	if (ret == 0)
640 		ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
641 			&tstamp, sizeof(tstamp)) ? -EFAULT : 0;
642 	return ret;
643 }
644 
645 static int snd_compr_pause(struct snd_compr_stream *stream)
646 {
647 	int retval;
648 
649 	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
650 		return -EPERM;
651 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
652 	if (!retval)
653 		stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
654 	return retval;
655 }
656 
657 static int snd_compr_resume(struct snd_compr_stream *stream)
658 {
659 	int retval;
660 
661 	if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
662 		return -EPERM;
663 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
664 	if (!retval)
665 		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
666 	return retval;
667 }
668 
669 static int snd_compr_start(struct snd_compr_stream *stream)
670 {
671 	int retval;
672 
673 	if (stream->runtime->state != SNDRV_PCM_STATE_PREPARED)
674 		return -EPERM;
675 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
676 	if (!retval)
677 		stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
678 	return retval;
679 }
680 
681 static int snd_compr_stop(struct snd_compr_stream *stream)
682 {
683 	int retval;
684 
685 	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
686 			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
687 		return -EPERM;
688 	retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
689 	if (!retval) {
690 		snd_compr_drain_notify(stream);
691 		stream->runtime->total_bytes_available = 0;
692 		stream->runtime->total_bytes_transferred = 0;
693 	}
694 	return retval;
695 }
696 
697 static int snd_compress_wait_for_drain(struct snd_compr_stream *stream)
698 {
699 	int ret;
700 
701 	/*
702 	 * We are called with lock held. So drop the lock while we wait for
703 	 * drain complete notfication from the driver
704 	 *
705 	 * It is expected that driver will notify the drain completion and then
706 	 * stream will be moved to SETUP state, even if draining resulted in an
707 	 * error. We can trigger next track after this.
708 	 */
709 	stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
710 	mutex_unlock(&stream->device->lock);
711 
712 	/* we wait for drain to complete here, drain can return when
713 	 * interruption occurred, wait returned error or success.
714 	 * For the first two cases we don't do anything different here and
715 	 * return after waking up
716 	 */
717 
718 	ret = wait_event_interruptible(stream->runtime->sleep,
719 			(stream->runtime->state != SNDRV_PCM_STATE_DRAINING));
720 	if (ret == -ERESTARTSYS)
721 		pr_debug("wait aborted by a signal");
722 	else if (ret)
723 		pr_debug("wait for drain failed with %d\n", ret);
724 
725 
726 	wake_up(&stream->runtime->sleep);
727 	mutex_lock(&stream->device->lock);
728 
729 	return ret;
730 }
731 
732 static int snd_compr_drain(struct snd_compr_stream *stream)
733 {
734 	int retval;
735 
736 	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
737 			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
738 		return -EPERM;
739 
740 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
741 	if (retval) {
742 		pr_debug("SND_COMPR_TRIGGER_DRAIN failed %d\n", retval);
743 		wake_up(&stream->runtime->sleep);
744 		return retval;
745 	}
746 
747 	return snd_compress_wait_for_drain(stream);
748 }
749 
750 static int snd_compr_next_track(struct snd_compr_stream *stream)
751 {
752 	int retval;
753 
754 	/* only a running stream can transition to next track */
755 	if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
756 		return -EPERM;
757 
758 	/* you can signal next track isf this is intended to be a gapless stream
759 	 * and current track metadata is set
760 	 */
761 	if (stream->metadata_set == false)
762 		return -EPERM;
763 
764 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
765 	if (retval != 0)
766 		return retval;
767 	stream->metadata_set = false;
768 	stream->next_track = true;
769 	return 0;
770 }
771 
772 static int snd_compr_partial_drain(struct snd_compr_stream *stream)
773 {
774 	int retval;
775 	if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
776 			stream->runtime->state == SNDRV_PCM_STATE_SETUP)
777 		return -EPERM;
778 	/* stream can be drained only when next track has been signalled */
779 	if (stream->next_track == false)
780 		return -EPERM;
781 
782 	retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
783 	if (retval) {
784 		pr_debug("Partial drain returned failure\n");
785 		wake_up(&stream->runtime->sleep);
786 		return retval;
787 	}
788 
789 	stream->next_track = false;
790 	return snd_compress_wait_for_drain(stream);
791 }
792 
793 static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
794 {
795 	struct snd_compr_file *data = f->private_data;
796 	struct snd_compr_stream *stream;
797 	int retval = -ENOTTY;
798 
799 	if (snd_BUG_ON(!data))
800 		return -EFAULT;
801 	stream = &data->stream;
802 	if (snd_BUG_ON(!stream))
803 		return -EFAULT;
804 	mutex_lock(&stream->device->lock);
805 	switch (_IOC_NR(cmd)) {
806 	case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
807 		retval = put_user(SNDRV_COMPRESS_VERSION,
808 				(int __user *)arg) ? -EFAULT : 0;
809 		break;
810 	case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
811 		retval = snd_compr_get_caps(stream, arg);
812 		break;
813 #ifndef COMPR_CODEC_CAPS_OVERFLOW
814 	case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
815 		retval = snd_compr_get_codec_caps(stream, arg);
816 		break;
817 #endif
818 	case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
819 		retval = snd_compr_set_params(stream, arg);
820 		break;
821 	case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
822 		retval = snd_compr_get_params(stream, arg);
823 		break;
824 	case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
825 		retval = snd_compr_set_metadata(stream, arg);
826 		break;
827 	case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
828 		retval = snd_compr_get_metadata(stream, arg);
829 		break;
830 	case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
831 		retval = snd_compr_tstamp(stream, arg);
832 		break;
833 	case _IOC_NR(SNDRV_COMPRESS_AVAIL):
834 		retval = snd_compr_ioctl_avail(stream, arg);
835 		break;
836 	case _IOC_NR(SNDRV_COMPRESS_PAUSE):
837 		retval = snd_compr_pause(stream);
838 		break;
839 	case _IOC_NR(SNDRV_COMPRESS_RESUME):
840 		retval = snd_compr_resume(stream);
841 		break;
842 	case _IOC_NR(SNDRV_COMPRESS_START):
843 		retval = snd_compr_start(stream);
844 		break;
845 	case _IOC_NR(SNDRV_COMPRESS_STOP):
846 		retval = snd_compr_stop(stream);
847 		break;
848 	case _IOC_NR(SNDRV_COMPRESS_DRAIN):
849 		retval = snd_compr_drain(stream);
850 		break;
851 	case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
852 		retval = snd_compr_partial_drain(stream);
853 		break;
854 	case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
855 		retval = snd_compr_next_track(stream);
856 		break;
857 
858 	}
859 	mutex_unlock(&stream->device->lock);
860 	return retval;
861 }
862 
863 /* support of 32bit userspace on 64bit platforms */
864 #ifdef CONFIG_COMPAT
865 static long snd_compr_ioctl_compat(struct file *file, unsigned int cmd,
866 						unsigned long arg)
867 {
868 	return snd_compr_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
869 }
870 #endif
871 
872 static const struct file_operations snd_compr_file_ops = {
873 		.owner =	THIS_MODULE,
874 		.open =		snd_compr_open,
875 		.release =	snd_compr_free,
876 		.write =	snd_compr_write,
877 		.read =		snd_compr_read,
878 		.unlocked_ioctl = snd_compr_ioctl,
879 #ifdef CONFIG_COMPAT
880 		.compat_ioctl = snd_compr_ioctl_compat,
881 #endif
882 		.mmap =		snd_compr_mmap,
883 		.poll =		snd_compr_poll,
884 };
885 
886 static int snd_compress_dev_register(struct snd_device *device)
887 {
888 	int ret = -EINVAL;
889 	char str[16];
890 	struct snd_compr *compr;
891 
892 	if (snd_BUG_ON(!device || !device->device_data))
893 		return -EBADFD;
894 	compr = device->device_data;
895 
896 	pr_debug("reg %s for device %s, direction %d\n", str, compr->name,
897 			compr->direction);
898 	/* register compressed device */
899 	ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS,
900 				  compr->card, compr->device,
901 				  &snd_compr_file_ops, compr, &compr->dev);
902 	if (ret < 0) {
903 		pr_err("snd_register_device failed\n %d", ret);
904 		return ret;
905 	}
906 	return ret;
907 
908 }
909 
910 static int snd_compress_dev_disconnect(struct snd_device *device)
911 {
912 	struct snd_compr *compr;
913 
914 	compr = device->device_data;
915 	snd_unregister_device(&compr->dev);
916 	return 0;
917 }
918 
919 #ifdef CONFIG_SND_VERBOSE_PROCFS
920 static void snd_compress_proc_info_read(struct snd_info_entry *entry,
921 					struct snd_info_buffer *buffer)
922 {
923 	struct snd_compr *compr = (struct snd_compr *)entry->private_data;
924 
925 	snd_iprintf(buffer, "card: %d\n", compr->card->number);
926 	snd_iprintf(buffer, "device: %d\n", compr->device);
927 	snd_iprintf(buffer, "stream: %s\n",
928 			compr->direction == SND_COMPRESS_PLAYBACK
929 				? "PLAYBACK" : "CAPTURE");
930 	snd_iprintf(buffer, "id: %s\n", compr->id);
931 }
932 
933 static int snd_compress_proc_init(struct snd_compr *compr)
934 {
935 	struct snd_info_entry *entry;
936 	char name[16];
937 
938 	sprintf(name, "compr%i", compr->device);
939 	entry = snd_info_create_card_entry(compr->card, name,
940 					   compr->card->proc_root);
941 	if (!entry)
942 		return -ENOMEM;
943 	entry->mode = S_IFDIR | S_IRUGO | S_IXUGO;
944 	if (snd_info_register(entry) < 0) {
945 		snd_info_free_entry(entry);
946 		return -ENOMEM;
947 	}
948 	compr->proc_root = entry;
949 
950 	entry = snd_info_create_card_entry(compr->card, "info",
951 					   compr->proc_root);
952 	if (entry) {
953 		snd_info_set_text_ops(entry, compr,
954 				      snd_compress_proc_info_read);
955 		if (snd_info_register(entry) < 0) {
956 			snd_info_free_entry(entry);
957 			entry = NULL;
958 		}
959 	}
960 	compr->proc_info_entry = entry;
961 
962 	return 0;
963 }
964 
965 static void snd_compress_proc_done(struct snd_compr *compr)
966 {
967 	snd_info_free_entry(compr->proc_info_entry);
968 	compr->proc_info_entry = NULL;
969 	snd_info_free_entry(compr->proc_root);
970 	compr->proc_root = NULL;
971 }
972 
973 static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
974 {
975 	strlcpy(compr->id, id, sizeof(compr->id));
976 }
977 #else
978 static inline int snd_compress_proc_init(struct snd_compr *compr)
979 {
980 	return 0;
981 }
982 
983 static inline void snd_compress_proc_done(struct snd_compr *compr)
984 {
985 }
986 
987 static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
988 {
989 }
990 #endif
991 
992 static int snd_compress_dev_free(struct snd_device *device)
993 {
994 	struct snd_compr *compr;
995 
996 	compr = device->device_data;
997 	snd_compress_proc_done(compr);
998 	put_device(&compr->dev);
999 	return 0;
1000 }
1001 
1002 /*
1003  * snd_compress_new: create new compress device
1004  * @card: sound card pointer
1005  * @device: device number
1006  * @dirn: device direction, should be of type enum snd_compr_direction
1007  * @compr: compress device pointer
1008  */
1009 int snd_compress_new(struct snd_card *card, int device,
1010 			int dirn, const char *id, struct snd_compr *compr)
1011 {
1012 	static struct snd_device_ops ops = {
1013 		.dev_free = snd_compress_dev_free,
1014 		.dev_register = snd_compress_dev_register,
1015 		.dev_disconnect = snd_compress_dev_disconnect,
1016 	};
1017 	int ret;
1018 
1019 	compr->card = card;
1020 	compr->device = device;
1021 	compr->direction = dirn;
1022 
1023 	snd_compress_set_id(compr, id);
1024 
1025 	snd_device_initialize(&compr->dev, card);
1026 	dev_set_name(&compr->dev, "comprC%iD%i", card->number, device);
1027 
1028 	ret = snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
1029 	if (ret == 0)
1030 		snd_compress_proc_init(compr);
1031 
1032 	return ret;
1033 }
1034 EXPORT_SYMBOL_GPL(snd_compress_new);
1035 
1036 static int snd_compress_add_device(struct snd_compr *device)
1037 {
1038 	int ret;
1039 
1040 	if (!device->card)
1041 		return -EINVAL;
1042 
1043 	/* register the card */
1044 	ret = snd_card_register(device->card);
1045 	if (ret)
1046 		goto out;
1047 	return 0;
1048 
1049 out:
1050 	pr_err("failed with %d\n", ret);
1051 	return ret;
1052 
1053 }
1054 
1055 static int snd_compress_remove_device(struct snd_compr *device)
1056 {
1057 	return snd_card_free(device->card);
1058 }
1059 
1060 /**
1061  * snd_compress_register - register compressed device
1062  *
1063  * @device: compressed device to register
1064  */
1065 int snd_compress_register(struct snd_compr *device)
1066 {
1067 	int retval;
1068 
1069 	if (device->name == NULL || device->ops == NULL)
1070 		return -EINVAL;
1071 
1072 	pr_debug("Registering compressed device %s\n", device->name);
1073 	if (snd_BUG_ON(!device->ops->open))
1074 		return -EINVAL;
1075 	if (snd_BUG_ON(!device->ops->free))
1076 		return -EINVAL;
1077 	if (snd_BUG_ON(!device->ops->set_params))
1078 		return -EINVAL;
1079 	if (snd_BUG_ON(!device->ops->trigger))
1080 		return -EINVAL;
1081 
1082 	mutex_init(&device->lock);
1083 
1084 	/* register a compressed card */
1085 	mutex_lock(&device_mutex);
1086 	retval = snd_compress_add_device(device);
1087 	mutex_unlock(&device_mutex);
1088 	return retval;
1089 }
1090 EXPORT_SYMBOL_GPL(snd_compress_register);
1091 
1092 int snd_compress_deregister(struct snd_compr *device)
1093 {
1094 	pr_debug("Removing compressed device %s\n", device->name);
1095 	mutex_lock(&device_mutex);
1096 	snd_compress_remove_device(device);
1097 	mutex_unlock(&device_mutex);
1098 	return 0;
1099 }
1100 EXPORT_SYMBOL_GPL(snd_compress_deregister);
1101 
1102 static int __init snd_compress_init(void)
1103 {
1104 	return 0;
1105 }
1106 
1107 static void __exit snd_compress_exit(void)
1108 {
1109 }
1110 
1111 module_init(snd_compress_init);
1112 module_exit(snd_compress_exit);
1113 
1114 MODULE_DESCRIPTION("ALSA Compressed offload framework");
1115 MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
1116 MODULE_LICENSE("GPL v2");
1117