xref: /openbmc/linux/sound/core/pcm_native.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Digital Audio (PCM) abstract layer
4  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5  */
6 
7 #include <linux/compat.h>
8 #include <linux/mm.h>
9 #include <linux/module.h>
10 #include <linux/file.h>
11 #include <linux/slab.h>
12 #include <linux/sched/signal.h>
13 #include <linux/time.h>
14 #include <linux/pm_qos.h>
15 #include <linux/io.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/vmalloc.h>
18 #include <sound/core.h>
19 #include <sound/control.h>
20 #include <sound/info.h>
21 #include <sound/pcm.h>
22 #include <sound/pcm_params.h>
23 #include <sound/timer.h>
24 #include <sound/minors.h>
25 #include <linux/uio.h>
26 #include <linux/delay.h>
27 
28 #include "pcm_local.h"
29 
30 #ifdef CONFIG_SND_DEBUG
31 #define CREATE_TRACE_POINTS
32 #include "pcm_param_trace.h"
33 #else
34 #define trace_hw_mask_param_enabled()		0
35 #define trace_hw_interval_param_enabled()	0
36 #define trace_hw_mask_param(substream, type, index, prev, curr)
37 #define trace_hw_interval_param(substream, type, index, prev, curr)
38 #endif
39 
40 /*
41  *  Compatibility
42  */
43 
44 struct snd_pcm_hw_params_old {
45 	unsigned int flags;
46 	unsigned int masks[SNDRV_PCM_HW_PARAM_SUBFORMAT -
47 			   SNDRV_PCM_HW_PARAM_ACCESS + 1];
48 	struct snd_interval intervals[SNDRV_PCM_HW_PARAM_TICK_TIME -
49 					SNDRV_PCM_HW_PARAM_SAMPLE_BITS + 1];
50 	unsigned int rmask;
51 	unsigned int cmask;
52 	unsigned int info;
53 	unsigned int msbits;
54 	unsigned int rate_num;
55 	unsigned int rate_den;
56 	snd_pcm_uframes_t fifo_size;
57 	unsigned char reserved[64];
58 };
59 
60 #ifdef CONFIG_SND_SUPPORT_OLD_API
61 #define SNDRV_PCM_IOCTL_HW_REFINE_OLD _IOWR('A', 0x10, struct snd_pcm_hw_params_old)
62 #define SNDRV_PCM_IOCTL_HW_PARAMS_OLD _IOWR('A', 0x11, struct snd_pcm_hw_params_old)
63 
64 static int snd_pcm_hw_refine_old_user(struct snd_pcm_substream *substream,
65 				      struct snd_pcm_hw_params_old __user * _oparams);
66 static int snd_pcm_hw_params_old_user(struct snd_pcm_substream *substream,
67 				      struct snd_pcm_hw_params_old __user * _oparams);
68 #endif
69 static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream);
70 
71 /*
72  *
73  */
74 
75 static DECLARE_RWSEM(snd_pcm_link_rwsem);
76 
77 void snd_pcm_group_init(struct snd_pcm_group *group)
78 {
79 	spin_lock_init(&group->lock);
80 	mutex_init(&group->mutex);
81 	INIT_LIST_HEAD(&group->substreams);
82 	refcount_set(&group->refs, 1);
83 }
84 
85 /* define group lock helpers */
86 #define DEFINE_PCM_GROUP_LOCK(action, mutex_action) \
87 static void snd_pcm_group_ ## action(struct snd_pcm_group *group, bool nonatomic) \
88 { \
89 	if (nonatomic) \
90 		mutex_ ## mutex_action(&group->mutex); \
91 	else \
92 		spin_ ## action(&group->lock); \
93 }
94 
95 DEFINE_PCM_GROUP_LOCK(lock, lock);
96 DEFINE_PCM_GROUP_LOCK(unlock, unlock);
97 DEFINE_PCM_GROUP_LOCK(lock_irq, lock);
98 DEFINE_PCM_GROUP_LOCK(unlock_irq, unlock);
99 
100 /**
101  * snd_pcm_stream_lock - Lock the PCM stream
102  * @substream: PCM substream
103  *
104  * This locks the PCM stream's spinlock or mutex depending on the nonatomic
105  * flag of the given substream.  This also takes the global link rw lock
106  * (or rw sem), too, for avoiding the race with linked streams.
107  */
108 void snd_pcm_stream_lock(struct snd_pcm_substream *substream)
109 {
110 	snd_pcm_group_lock(&substream->self_group, substream->pcm->nonatomic);
111 }
112 EXPORT_SYMBOL_GPL(snd_pcm_stream_lock);
113 
114 /**
115  * snd_pcm_stream_unlock - Unlock the PCM stream
116  * @substream: PCM substream
117  *
118  * This unlocks the PCM stream that has been locked via snd_pcm_stream_lock().
119  */
120 void snd_pcm_stream_unlock(struct snd_pcm_substream *substream)
121 {
122 	snd_pcm_group_unlock(&substream->self_group, substream->pcm->nonatomic);
123 }
124 EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock);
125 
126 /**
127  * snd_pcm_stream_lock_irq - Lock the PCM stream
128  * @substream: PCM substream
129  *
130  * This locks the PCM stream like snd_pcm_stream_lock() and disables the local
131  * IRQ (only when nonatomic is false).  In nonatomic case, this is identical
132  * as snd_pcm_stream_lock().
133  */
134 void snd_pcm_stream_lock_irq(struct snd_pcm_substream *substream)
135 {
136 	snd_pcm_group_lock_irq(&substream->self_group,
137 			       substream->pcm->nonatomic);
138 }
139 EXPORT_SYMBOL_GPL(snd_pcm_stream_lock_irq);
140 
141 static void snd_pcm_stream_lock_nested(struct snd_pcm_substream *substream)
142 {
143 	struct snd_pcm_group *group = &substream->self_group;
144 
145 	if (substream->pcm->nonatomic)
146 		mutex_lock_nested(&group->mutex, SINGLE_DEPTH_NESTING);
147 	else
148 		spin_lock_nested(&group->lock, SINGLE_DEPTH_NESTING);
149 }
150 
151 /**
152  * snd_pcm_stream_unlock_irq - Unlock the PCM stream
153  * @substream: PCM substream
154  *
155  * This is a counter-part of snd_pcm_stream_lock_irq().
156  */
157 void snd_pcm_stream_unlock_irq(struct snd_pcm_substream *substream)
158 {
159 	snd_pcm_group_unlock_irq(&substream->self_group,
160 				 substream->pcm->nonatomic);
161 }
162 EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irq);
163 
164 unsigned long _snd_pcm_stream_lock_irqsave(struct snd_pcm_substream *substream)
165 {
166 	unsigned long flags = 0;
167 	if (substream->pcm->nonatomic)
168 		mutex_lock(&substream->self_group.mutex);
169 	else
170 		spin_lock_irqsave(&substream->self_group.lock, flags);
171 	return flags;
172 }
173 EXPORT_SYMBOL_GPL(_snd_pcm_stream_lock_irqsave);
174 
175 /**
176  * snd_pcm_stream_unlock_irqrestore - Unlock the PCM stream
177  * @substream: PCM substream
178  * @flags: irq flags
179  *
180  * This is a counter-part of snd_pcm_stream_lock_irqsave().
181  */
182 void snd_pcm_stream_unlock_irqrestore(struct snd_pcm_substream *substream,
183 				      unsigned long flags)
184 {
185 	if (substream->pcm->nonatomic)
186 		mutex_unlock(&substream->self_group.mutex);
187 	else
188 		spin_unlock_irqrestore(&substream->self_group.lock, flags);
189 }
190 EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irqrestore);
191 
192 /* Run PCM ioctl ops */
193 static int snd_pcm_ops_ioctl(struct snd_pcm_substream *substream,
194 			     unsigned cmd, void *arg)
195 {
196 	if (substream->ops->ioctl)
197 		return substream->ops->ioctl(substream, cmd, arg);
198 	else
199 		return snd_pcm_lib_ioctl(substream, cmd, arg);
200 }
201 
202 int snd_pcm_info(struct snd_pcm_substream *substream, struct snd_pcm_info *info)
203 {
204 	struct snd_pcm *pcm = substream->pcm;
205 	struct snd_pcm_str *pstr = substream->pstr;
206 
207 	memset(info, 0, sizeof(*info));
208 	info->card = pcm->card->number;
209 	info->device = pcm->device;
210 	info->stream = substream->stream;
211 	info->subdevice = substream->number;
212 	strscpy(info->id, pcm->id, sizeof(info->id));
213 	strscpy(info->name, pcm->name, sizeof(info->name));
214 	info->dev_class = pcm->dev_class;
215 	info->dev_subclass = pcm->dev_subclass;
216 	info->subdevices_count = pstr->substream_count;
217 	info->subdevices_avail = pstr->substream_count - pstr->substream_opened;
218 	strscpy(info->subname, substream->name, sizeof(info->subname));
219 
220 	return 0;
221 }
222 
223 int snd_pcm_info_user(struct snd_pcm_substream *substream,
224 		      struct snd_pcm_info __user * _info)
225 {
226 	struct snd_pcm_info *info;
227 	int err;
228 
229 	info = kmalloc(sizeof(*info), GFP_KERNEL);
230 	if (! info)
231 		return -ENOMEM;
232 	err = snd_pcm_info(substream, info);
233 	if (err >= 0) {
234 		if (copy_to_user(_info, info, sizeof(*info)))
235 			err = -EFAULT;
236 	}
237 	kfree(info);
238 	return err;
239 }
240 
241 /* macro for simplified cast */
242 #define PARAM_MASK_BIT(b)	(1U << (__force int)(b))
243 
244 static bool hw_support_mmap(struct snd_pcm_substream *substream)
245 {
246 	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP))
247 		return false;
248 
249 	if (substream->ops->mmap ||
250 	    (substream->dma_buffer.dev.type != SNDRV_DMA_TYPE_DEV &&
251 	     substream->dma_buffer.dev.type != SNDRV_DMA_TYPE_DEV_UC))
252 		return true;
253 
254 	return dma_can_mmap(substream->dma_buffer.dev.dev);
255 }
256 
257 static int constrain_mask_params(struct snd_pcm_substream *substream,
258 				 struct snd_pcm_hw_params *params)
259 {
260 	struct snd_pcm_hw_constraints *constrs =
261 					&substream->runtime->hw_constraints;
262 	struct snd_mask *m;
263 	unsigned int k;
264 	struct snd_mask old_mask;
265 	int changed;
266 
267 	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++) {
268 		m = hw_param_mask(params, k);
269 		if (snd_mask_empty(m))
270 			return -EINVAL;
271 
272 		/* This parameter is not requested to change by a caller. */
273 		if (!(params->rmask & PARAM_MASK_BIT(k)))
274 			continue;
275 
276 		if (trace_hw_mask_param_enabled())
277 			old_mask = *m;
278 
279 		changed = snd_mask_refine(m, constrs_mask(constrs, k));
280 		if (changed < 0)
281 			return changed;
282 		if (changed == 0)
283 			continue;
284 
285 		/* Set corresponding flag so that the caller gets it. */
286 		trace_hw_mask_param(substream, k, 0, &old_mask, m);
287 		params->cmask |= PARAM_MASK_BIT(k);
288 	}
289 
290 	return 0;
291 }
292 
293 static int constrain_interval_params(struct snd_pcm_substream *substream,
294 				     struct snd_pcm_hw_params *params)
295 {
296 	struct snd_pcm_hw_constraints *constrs =
297 					&substream->runtime->hw_constraints;
298 	struct snd_interval *i;
299 	unsigned int k;
300 	struct snd_interval old_interval;
301 	int changed;
302 
303 	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++) {
304 		i = hw_param_interval(params, k);
305 		if (snd_interval_empty(i))
306 			return -EINVAL;
307 
308 		/* This parameter is not requested to change by a caller. */
309 		if (!(params->rmask & PARAM_MASK_BIT(k)))
310 			continue;
311 
312 		if (trace_hw_interval_param_enabled())
313 			old_interval = *i;
314 
315 		changed = snd_interval_refine(i, constrs_interval(constrs, k));
316 		if (changed < 0)
317 			return changed;
318 		if (changed == 0)
319 			continue;
320 
321 		/* Set corresponding flag so that the caller gets it. */
322 		trace_hw_interval_param(substream, k, 0, &old_interval, i);
323 		params->cmask |= PARAM_MASK_BIT(k);
324 	}
325 
326 	return 0;
327 }
328 
329 static int constrain_params_by_rules(struct snd_pcm_substream *substream,
330 				     struct snd_pcm_hw_params *params)
331 {
332 	struct snd_pcm_hw_constraints *constrs =
333 					&substream->runtime->hw_constraints;
334 	unsigned int k;
335 	unsigned int *rstamps;
336 	unsigned int vstamps[SNDRV_PCM_HW_PARAM_LAST_INTERVAL + 1];
337 	unsigned int stamp;
338 	struct snd_pcm_hw_rule *r;
339 	unsigned int d;
340 	struct snd_mask old_mask;
341 	struct snd_interval old_interval;
342 	bool again;
343 	int changed, err = 0;
344 
345 	/*
346 	 * Each application of rule has own sequence number.
347 	 *
348 	 * Each member of 'rstamps' array represents the sequence number of
349 	 * recent application of corresponding rule.
350 	 */
351 	rstamps = kcalloc(constrs->rules_num, sizeof(unsigned int), GFP_KERNEL);
352 	if (!rstamps)
353 		return -ENOMEM;
354 
355 	/*
356 	 * Each member of 'vstamps' array represents the sequence number of
357 	 * recent application of rule in which corresponding parameters were
358 	 * changed.
359 	 *
360 	 * In initial state, elements corresponding to parameters requested by
361 	 * a caller is 1. For unrequested parameters, corresponding members
362 	 * have 0 so that the parameters are never changed anymore.
363 	 */
364 	for (k = 0; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
365 		vstamps[k] = (params->rmask & PARAM_MASK_BIT(k)) ? 1 : 0;
366 
367 	/* Due to the above design, actual sequence number starts at 2. */
368 	stamp = 2;
369 retry:
370 	/* Apply all rules in order. */
371 	again = false;
372 	for (k = 0; k < constrs->rules_num; k++) {
373 		r = &constrs->rules[k];
374 
375 		/*
376 		 * Check condition bits of this rule. When the rule has
377 		 * some condition bits, parameter without the bits is
378 		 * never processed. SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP
379 		 * is an example of the condition bits.
380 		 */
381 		if (r->cond && !(r->cond & params->flags))
382 			continue;
383 
384 		/*
385 		 * The 'deps' array includes maximum four dependencies
386 		 * to SNDRV_PCM_HW_PARAM_XXXs for this rule. The fifth
387 		 * member of this array is a sentinel and should be
388 		 * negative value.
389 		 *
390 		 * This rule should be processed in this time when dependent
391 		 * parameters were changed at former applications of the other
392 		 * rules.
393 		 */
394 		for (d = 0; r->deps[d] >= 0; d++) {
395 			if (vstamps[r->deps[d]] > rstamps[k])
396 				break;
397 		}
398 		if (r->deps[d] < 0)
399 			continue;
400 
401 		if (trace_hw_mask_param_enabled()) {
402 			if (hw_is_mask(r->var))
403 				old_mask = *hw_param_mask(params, r->var);
404 		}
405 		if (trace_hw_interval_param_enabled()) {
406 			if (hw_is_interval(r->var))
407 				old_interval = *hw_param_interval(params, r->var);
408 		}
409 
410 		changed = r->func(params, r);
411 		if (changed < 0) {
412 			err = changed;
413 			goto out;
414 		}
415 
416 		/*
417 		 * When the parameter is changed, notify it to the caller
418 		 * by corresponding returned bit, then preparing for next
419 		 * iteration.
420 		 */
421 		if (changed && r->var >= 0) {
422 			if (hw_is_mask(r->var)) {
423 				trace_hw_mask_param(substream, r->var,
424 					k + 1, &old_mask,
425 					hw_param_mask(params, r->var));
426 			}
427 			if (hw_is_interval(r->var)) {
428 				trace_hw_interval_param(substream, r->var,
429 					k + 1, &old_interval,
430 					hw_param_interval(params, r->var));
431 			}
432 
433 			params->cmask |= PARAM_MASK_BIT(r->var);
434 			vstamps[r->var] = stamp;
435 			again = true;
436 		}
437 
438 		rstamps[k] = stamp++;
439 	}
440 
441 	/* Iterate to evaluate all rules till no parameters are changed. */
442 	if (again)
443 		goto retry;
444 
445  out:
446 	kfree(rstamps);
447 	return err;
448 }
449 
450 static int fixup_unreferenced_params(struct snd_pcm_substream *substream,
451 				     struct snd_pcm_hw_params *params)
452 {
453 	const struct snd_interval *i;
454 	const struct snd_mask *m;
455 	int err;
456 
457 	if (!params->msbits) {
458 		i = hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
459 		if (snd_interval_single(i))
460 			params->msbits = snd_interval_value(i);
461 	}
462 
463 	if (!params->rate_den) {
464 		i = hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_RATE);
465 		if (snd_interval_single(i)) {
466 			params->rate_num = snd_interval_value(i);
467 			params->rate_den = 1;
468 		}
469 	}
470 
471 	if (!params->fifo_size) {
472 		m = hw_param_mask_c(params, SNDRV_PCM_HW_PARAM_FORMAT);
473 		i = hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_CHANNELS);
474 		if (snd_mask_single(m) && snd_interval_single(i)) {
475 			err = snd_pcm_ops_ioctl(substream,
476 						SNDRV_PCM_IOCTL1_FIFO_SIZE,
477 						params);
478 			if (err < 0)
479 				return err;
480 		}
481 	}
482 
483 	if (!params->info) {
484 		params->info = substream->runtime->hw.info;
485 		params->info &= ~(SNDRV_PCM_INFO_FIFO_IN_FRAMES |
486 				  SNDRV_PCM_INFO_DRAIN_TRIGGER);
487 		if (!hw_support_mmap(substream))
488 			params->info &= ~(SNDRV_PCM_INFO_MMAP |
489 					  SNDRV_PCM_INFO_MMAP_VALID);
490 	}
491 
492 	return 0;
493 }
494 
495 int snd_pcm_hw_refine(struct snd_pcm_substream *substream,
496 		      struct snd_pcm_hw_params *params)
497 {
498 	int err;
499 
500 	params->info = 0;
501 	params->fifo_size = 0;
502 	if (params->rmask & PARAM_MASK_BIT(SNDRV_PCM_HW_PARAM_SAMPLE_BITS))
503 		params->msbits = 0;
504 	if (params->rmask & PARAM_MASK_BIT(SNDRV_PCM_HW_PARAM_RATE)) {
505 		params->rate_num = 0;
506 		params->rate_den = 0;
507 	}
508 
509 	err = constrain_mask_params(substream, params);
510 	if (err < 0)
511 		return err;
512 
513 	err = constrain_interval_params(substream, params);
514 	if (err < 0)
515 		return err;
516 
517 	err = constrain_params_by_rules(substream, params);
518 	if (err < 0)
519 		return err;
520 
521 	params->rmask = 0;
522 
523 	return 0;
524 }
525 EXPORT_SYMBOL(snd_pcm_hw_refine);
526 
527 static int snd_pcm_hw_refine_user(struct snd_pcm_substream *substream,
528 				  struct snd_pcm_hw_params __user * _params)
529 {
530 	struct snd_pcm_hw_params *params;
531 	int err;
532 
533 	params = memdup_user(_params, sizeof(*params));
534 	if (IS_ERR(params))
535 		return PTR_ERR(params);
536 
537 	err = snd_pcm_hw_refine(substream, params);
538 	if (err < 0)
539 		goto end;
540 
541 	err = fixup_unreferenced_params(substream, params);
542 	if (err < 0)
543 		goto end;
544 
545 	if (copy_to_user(_params, params, sizeof(*params)))
546 		err = -EFAULT;
547 end:
548 	kfree(params);
549 	return err;
550 }
551 
552 static int period_to_usecs(struct snd_pcm_runtime *runtime)
553 {
554 	int usecs;
555 
556 	if (! runtime->rate)
557 		return -1; /* invalid */
558 
559 	/* take 75% of period time as the deadline */
560 	usecs = (750000 / runtime->rate) * runtime->period_size;
561 	usecs += ((750000 % runtime->rate) * runtime->period_size) /
562 		runtime->rate;
563 
564 	return usecs;
565 }
566 
567 static void snd_pcm_set_state(struct snd_pcm_substream *substream,
568 			      snd_pcm_state_t state)
569 {
570 	snd_pcm_stream_lock_irq(substream);
571 	if (substream->runtime->status->state != SNDRV_PCM_STATE_DISCONNECTED)
572 		substream->runtime->status->state = state;
573 	snd_pcm_stream_unlock_irq(substream);
574 }
575 
576 static inline void snd_pcm_timer_notify(struct snd_pcm_substream *substream,
577 					int event)
578 {
579 #ifdef CONFIG_SND_PCM_TIMER
580 	if (substream->timer)
581 		snd_timer_notify(substream->timer, event,
582 					&substream->runtime->trigger_tstamp);
583 #endif
584 }
585 
586 void snd_pcm_sync_stop(struct snd_pcm_substream *substream, bool sync_irq)
587 {
588 	if (substream->runtime && substream->runtime->stop_operating) {
589 		substream->runtime->stop_operating = false;
590 		if (substream->ops && substream->ops->sync_stop)
591 			substream->ops->sync_stop(substream);
592 		else if (sync_irq && substream->pcm->card->sync_irq > 0)
593 			synchronize_irq(substream->pcm->card->sync_irq);
594 	}
595 }
596 
597 /**
598  * snd_pcm_hw_params_choose - choose a configuration defined by @params
599  * @pcm: PCM instance
600  * @params: the hw_params instance
601  *
602  * Choose one configuration from configuration space defined by @params.
603  * The configuration chosen is that obtained fixing in this order:
604  * first access, first format, first subformat, min channels,
605  * min rate, min period time, max buffer size, min tick time
606  *
607  * Return: Zero if successful, or a negative error code on failure.
608  */
609 static int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
610 				    struct snd_pcm_hw_params *params)
611 {
612 	static const int vars[] = {
613 		SNDRV_PCM_HW_PARAM_ACCESS,
614 		SNDRV_PCM_HW_PARAM_FORMAT,
615 		SNDRV_PCM_HW_PARAM_SUBFORMAT,
616 		SNDRV_PCM_HW_PARAM_CHANNELS,
617 		SNDRV_PCM_HW_PARAM_RATE,
618 		SNDRV_PCM_HW_PARAM_PERIOD_TIME,
619 		SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
620 		SNDRV_PCM_HW_PARAM_TICK_TIME,
621 		-1
622 	};
623 	const int *v;
624 	struct snd_mask old_mask;
625 	struct snd_interval old_interval;
626 	int changed;
627 
628 	for (v = vars; *v != -1; v++) {
629 		/* Keep old parameter to trace. */
630 		if (trace_hw_mask_param_enabled()) {
631 			if (hw_is_mask(*v))
632 				old_mask = *hw_param_mask(params, *v);
633 		}
634 		if (trace_hw_interval_param_enabled()) {
635 			if (hw_is_interval(*v))
636 				old_interval = *hw_param_interval(params, *v);
637 		}
638 		if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
639 			changed = snd_pcm_hw_param_first(pcm, params, *v, NULL);
640 		else
641 			changed = snd_pcm_hw_param_last(pcm, params, *v, NULL);
642 		if (changed < 0)
643 			return changed;
644 		if (changed == 0)
645 			continue;
646 
647 		/* Trace the changed parameter. */
648 		if (hw_is_mask(*v)) {
649 			trace_hw_mask_param(pcm, *v, 0, &old_mask,
650 					    hw_param_mask(params, *v));
651 		}
652 		if (hw_is_interval(*v)) {
653 			trace_hw_interval_param(pcm, *v, 0, &old_interval,
654 						hw_param_interval(params, *v));
655 		}
656 	}
657 
658 	return 0;
659 }
660 
661 static int snd_pcm_hw_params(struct snd_pcm_substream *substream,
662 			     struct snd_pcm_hw_params *params)
663 {
664 	struct snd_pcm_runtime *runtime;
665 	int err, usecs;
666 	unsigned int bits;
667 	snd_pcm_uframes_t frames;
668 
669 	if (PCM_RUNTIME_CHECK(substream))
670 		return -ENXIO;
671 	runtime = substream->runtime;
672 	snd_pcm_stream_lock_irq(substream);
673 	switch (runtime->status->state) {
674 	case SNDRV_PCM_STATE_OPEN:
675 	case SNDRV_PCM_STATE_SETUP:
676 	case SNDRV_PCM_STATE_PREPARED:
677 		break;
678 	default:
679 		snd_pcm_stream_unlock_irq(substream);
680 		return -EBADFD;
681 	}
682 	snd_pcm_stream_unlock_irq(substream);
683 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
684 	if (!substream->oss.oss)
685 #endif
686 		if (atomic_read(&substream->mmap_count))
687 			return -EBADFD;
688 
689 	snd_pcm_sync_stop(substream, true);
690 
691 	params->rmask = ~0U;
692 	err = snd_pcm_hw_refine(substream, params);
693 	if (err < 0)
694 		goto _error;
695 
696 	err = snd_pcm_hw_params_choose(substream, params);
697 	if (err < 0)
698 		goto _error;
699 
700 	err = fixup_unreferenced_params(substream, params);
701 	if (err < 0)
702 		goto _error;
703 
704 	if (substream->managed_buffer_alloc) {
705 		err = snd_pcm_lib_malloc_pages(substream,
706 					       params_buffer_bytes(params));
707 		if (err < 0)
708 			goto _error;
709 		runtime->buffer_changed = err > 0;
710 	}
711 
712 	if (substream->ops->hw_params != NULL) {
713 		err = substream->ops->hw_params(substream, params);
714 		if (err < 0)
715 			goto _error;
716 	}
717 
718 	runtime->access = params_access(params);
719 	runtime->format = params_format(params);
720 	runtime->subformat = params_subformat(params);
721 	runtime->channels = params_channels(params);
722 	runtime->rate = params_rate(params);
723 	runtime->period_size = params_period_size(params);
724 	runtime->periods = params_periods(params);
725 	runtime->buffer_size = params_buffer_size(params);
726 	runtime->info = params->info;
727 	runtime->rate_num = params->rate_num;
728 	runtime->rate_den = params->rate_den;
729 	runtime->no_period_wakeup =
730 			(params->info & SNDRV_PCM_INFO_NO_PERIOD_WAKEUP) &&
731 			(params->flags & SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP);
732 
733 	bits = snd_pcm_format_physical_width(runtime->format);
734 	runtime->sample_bits = bits;
735 	bits *= runtime->channels;
736 	runtime->frame_bits = bits;
737 	frames = 1;
738 	while (bits % 8 != 0) {
739 		bits *= 2;
740 		frames *= 2;
741 	}
742 	runtime->byte_align = bits / 8;
743 	runtime->min_align = frames;
744 
745 	/* Default sw params */
746 	runtime->tstamp_mode = SNDRV_PCM_TSTAMP_NONE;
747 	runtime->period_step = 1;
748 	runtime->control->avail_min = runtime->period_size;
749 	runtime->start_threshold = 1;
750 	runtime->stop_threshold = runtime->buffer_size;
751 	runtime->silence_threshold = 0;
752 	runtime->silence_size = 0;
753 	runtime->boundary = runtime->buffer_size;
754 	while (runtime->boundary * 2 <= LONG_MAX - runtime->buffer_size)
755 		runtime->boundary *= 2;
756 
757 	/* clear the buffer for avoiding possible kernel info leaks */
758 	if (runtime->dma_area && !substream->ops->copy_user) {
759 		size_t size = runtime->dma_bytes;
760 
761 		if (runtime->info & SNDRV_PCM_INFO_MMAP)
762 			size = PAGE_ALIGN(size);
763 		memset(runtime->dma_area, 0, size);
764 	}
765 
766 	snd_pcm_timer_resolution_change(substream);
767 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_SETUP);
768 
769 	if (cpu_latency_qos_request_active(&substream->latency_pm_qos_req))
770 		cpu_latency_qos_remove_request(&substream->latency_pm_qos_req);
771 	if ((usecs = period_to_usecs(runtime)) >= 0)
772 		cpu_latency_qos_add_request(&substream->latency_pm_qos_req,
773 					    usecs);
774 	return 0;
775  _error:
776 	/* hardware might be unusable from this time,
777 	   so we force application to retry to set
778 	   the correct hardware parameter settings */
779 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_OPEN);
780 	if (substream->ops->hw_free != NULL)
781 		substream->ops->hw_free(substream);
782 	if (substream->managed_buffer_alloc)
783 		snd_pcm_lib_free_pages(substream);
784 	return err;
785 }
786 
787 static int snd_pcm_hw_params_user(struct snd_pcm_substream *substream,
788 				  struct snd_pcm_hw_params __user * _params)
789 {
790 	struct snd_pcm_hw_params *params;
791 	int err;
792 
793 	params = memdup_user(_params, sizeof(*params));
794 	if (IS_ERR(params))
795 		return PTR_ERR(params);
796 
797 	err = snd_pcm_hw_params(substream, params);
798 	if (err < 0)
799 		goto end;
800 
801 	if (copy_to_user(_params, params, sizeof(*params)))
802 		err = -EFAULT;
803 end:
804 	kfree(params);
805 	return err;
806 }
807 
808 static int do_hw_free(struct snd_pcm_substream *substream)
809 {
810 	int result = 0;
811 
812 	snd_pcm_sync_stop(substream, true);
813 	if (substream->ops->hw_free)
814 		result = substream->ops->hw_free(substream);
815 	if (substream->managed_buffer_alloc)
816 		snd_pcm_lib_free_pages(substream);
817 	return result;
818 }
819 
820 static int snd_pcm_hw_free(struct snd_pcm_substream *substream)
821 {
822 	struct snd_pcm_runtime *runtime;
823 	int result;
824 
825 	if (PCM_RUNTIME_CHECK(substream))
826 		return -ENXIO;
827 	runtime = substream->runtime;
828 	snd_pcm_stream_lock_irq(substream);
829 	switch (runtime->status->state) {
830 	case SNDRV_PCM_STATE_SETUP:
831 	case SNDRV_PCM_STATE_PREPARED:
832 		break;
833 	default:
834 		snd_pcm_stream_unlock_irq(substream);
835 		return -EBADFD;
836 	}
837 	snd_pcm_stream_unlock_irq(substream);
838 	if (atomic_read(&substream->mmap_count))
839 		return -EBADFD;
840 	result = do_hw_free(substream);
841 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_OPEN);
842 	cpu_latency_qos_remove_request(&substream->latency_pm_qos_req);
843 	return result;
844 }
845 
846 static int snd_pcm_sw_params(struct snd_pcm_substream *substream,
847 			     struct snd_pcm_sw_params *params)
848 {
849 	struct snd_pcm_runtime *runtime;
850 	int err;
851 
852 	if (PCM_RUNTIME_CHECK(substream))
853 		return -ENXIO;
854 	runtime = substream->runtime;
855 	snd_pcm_stream_lock_irq(substream);
856 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
857 		snd_pcm_stream_unlock_irq(substream);
858 		return -EBADFD;
859 	}
860 	snd_pcm_stream_unlock_irq(substream);
861 
862 	if (params->tstamp_mode < 0 ||
863 	    params->tstamp_mode > SNDRV_PCM_TSTAMP_LAST)
864 		return -EINVAL;
865 	if (params->proto >= SNDRV_PROTOCOL_VERSION(2, 0, 12) &&
866 	    params->tstamp_type > SNDRV_PCM_TSTAMP_TYPE_LAST)
867 		return -EINVAL;
868 	if (params->avail_min == 0)
869 		return -EINVAL;
870 	if (params->silence_size >= runtime->boundary) {
871 		if (params->silence_threshold != 0)
872 			return -EINVAL;
873 	} else {
874 		if (params->silence_size > params->silence_threshold)
875 			return -EINVAL;
876 		if (params->silence_threshold > runtime->buffer_size)
877 			return -EINVAL;
878 	}
879 	err = 0;
880 	snd_pcm_stream_lock_irq(substream);
881 	runtime->tstamp_mode = params->tstamp_mode;
882 	if (params->proto >= SNDRV_PROTOCOL_VERSION(2, 0, 12))
883 		runtime->tstamp_type = params->tstamp_type;
884 	runtime->period_step = params->period_step;
885 	runtime->control->avail_min = params->avail_min;
886 	runtime->start_threshold = params->start_threshold;
887 	runtime->stop_threshold = params->stop_threshold;
888 	runtime->silence_threshold = params->silence_threshold;
889 	runtime->silence_size = params->silence_size;
890         params->boundary = runtime->boundary;
891 	if (snd_pcm_running(substream)) {
892 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
893 		    runtime->silence_size > 0)
894 			snd_pcm_playback_silence(substream, ULONG_MAX);
895 		err = snd_pcm_update_state(substream, runtime);
896 	}
897 	snd_pcm_stream_unlock_irq(substream);
898 	return err;
899 }
900 
901 static int snd_pcm_sw_params_user(struct snd_pcm_substream *substream,
902 				  struct snd_pcm_sw_params __user * _params)
903 {
904 	struct snd_pcm_sw_params params;
905 	int err;
906 	if (copy_from_user(&params, _params, sizeof(params)))
907 		return -EFAULT;
908 	err = snd_pcm_sw_params(substream, &params);
909 	if (copy_to_user(_params, &params, sizeof(params)))
910 		return -EFAULT;
911 	return err;
912 }
913 
914 static inline snd_pcm_uframes_t
915 snd_pcm_calc_delay(struct snd_pcm_substream *substream)
916 {
917 	snd_pcm_uframes_t delay;
918 
919 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
920 		delay = snd_pcm_playback_hw_avail(substream->runtime);
921 	else
922 		delay = snd_pcm_capture_avail(substream->runtime);
923 	return delay + substream->runtime->delay;
924 }
925 
926 int snd_pcm_status64(struct snd_pcm_substream *substream,
927 		     struct snd_pcm_status64 *status)
928 {
929 	struct snd_pcm_runtime *runtime = substream->runtime;
930 
931 	snd_pcm_stream_lock_irq(substream);
932 
933 	snd_pcm_unpack_audio_tstamp_config(status->audio_tstamp_data,
934 					&runtime->audio_tstamp_config);
935 
936 	/* backwards compatible behavior */
937 	if (runtime->audio_tstamp_config.type_requested ==
938 		SNDRV_PCM_AUDIO_TSTAMP_TYPE_COMPAT) {
939 		if (runtime->hw.info & SNDRV_PCM_INFO_HAS_WALL_CLOCK)
940 			runtime->audio_tstamp_config.type_requested =
941 				SNDRV_PCM_AUDIO_TSTAMP_TYPE_LINK;
942 		else
943 			runtime->audio_tstamp_config.type_requested =
944 				SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT;
945 		runtime->audio_tstamp_report.valid = 0;
946 	} else
947 		runtime->audio_tstamp_report.valid = 1;
948 
949 	status->state = runtime->status->state;
950 	status->suspended_state = runtime->status->suspended_state;
951 	if (status->state == SNDRV_PCM_STATE_OPEN)
952 		goto _end;
953 	status->trigger_tstamp_sec = runtime->trigger_tstamp.tv_sec;
954 	status->trigger_tstamp_nsec = runtime->trigger_tstamp.tv_nsec;
955 	if (snd_pcm_running(substream)) {
956 		snd_pcm_update_hw_ptr(substream);
957 		if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
958 			status->tstamp_sec = runtime->status->tstamp.tv_sec;
959 			status->tstamp_nsec =
960 				runtime->status->tstamp.tv_nsec;
961 			status->driver_tstamp_sec =
962 				runtime->driver_tstamp.tv_sec;
963 			status->driver_tstamp_nsec =
964 				runtime->driver_tstamp.tv_nsec;
965 			status->audio_tstamp_sec =
966 				runtime->status->audio_tstamp.tv_sec;
967 			status->audio_tstamp_nsec =
968 				runtime->status->audio_tstamp.tv_nsec;
969 			if (runtime->audio_tstamp_report.valid == 1)
970 				/* backwards compatibility, no report provided in COMPAT mode */
971 				snd_pcm_pack_audio_tstamp_report(&status->audio_tstamp_data,
972 								&status->audio_tstamp_accuracy,
973 								&runtime->audio_tstamp_report);
974 
975 			goto _tstamp_end;
976 		}
977 	} else {
978 		/* get tstamp only in fallback mode and only if enabled */
979 		if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
980 			struct timespec64 tstamp;
981 
982 			snd_pcm_gettime(runtime, &tstamp);
983 			status->tstamp_sec = tstamp.tv_sec;
984 			status->tstamp_nsec = tstamp.tv_nsec;
985 		}
986 	}
987  _tstamp_end:
988 	status->appl_ptr = runtime->control->appl_ptr;
989 	status->hw_ptr = runtime->status->hw_ptr;
990 	status->avail = snd_pcm_avail(substream);
991 	status->delay = snd_pcm_running(substream) ?
992 		snd_pcm_calc_delay(substream) : 0;
993 	status->avail_max = runtime->avail_max;
994 	status->overrange = runtime->overrange;
995 	runtime->avail_max = 0;
996 	runtime->overrange = 0;
997  _end:
998  	snd_pcm_stream_unlock_irq(substream);
999 	return 0;
1000 }
1001 
1002 static int snd_pcm_status_user64(struct snd_pcm_substream *substream,
1003 				 struct snd_pcm_status64 __user * _status,
1004 				 bool ext)
1005 {
1006 	struct snd_pcm_status64 status;
1007 	int res;
1008 
1009 	memset(&status, 0, sizeof(status));
1010 	/*
1011 	 * with extension, parameters are read/write,
1012 	 * get audio_tstamp_data from user,
1013 	 * ignore rest of status structure
1014 	 */
1015 	if (ext && get_user(status.audio_tstamp_data,
1016 				(u32 __user *)(&_status->audio_tstamp_data)))
1017 		return -EFAULT;
1018 	res = snd_pcm_status64(substream, &status);
1019 	if (res < 0)
1020 		return res;
1021 	if (copy_to_user(_status, &status, sizeof(status)))
1022 		return -EFAULT;
1023 	return 0;
1024 }
1025 
1026 static int snd_pcm_status_user32(struct snd_pcm_substream *substream,
1027 				 struct snd_pcm_status32 __user * _status,
1028 				 bool ext)
1029 {
1030 	struct snd_pcm_status64 status64;
1031 	struct snd_pcm_status32 status32;
1032 	int res;
1033 
1034 	memset(&status64, 0, sizeof(status64));
1035 	memset(&status32, 0, sizeof(status32));
1036 	/*
1037 	 * with extension, parameters are read/write,
1038 	 * get audio_tstamp_data from user,
1039 	 * ignore rest of status structure
1040 	 */
1041 	if (ext && get_user(status64.audio_tstamp_data,
1042 			    (u32 __user *)(&_status->audio_tstamp_data)))
1043 		return -EFAULT;
1044 	res = snd_pcm_status64(substream, &status64);
1045 	if (res < 0)
1046 		return res;
1047 
1048 	status32 = (struct snd_pcm_status32) {
1049 		.state = status64.state,
1050 		.trigger_tstamp_sec = status64.trigger_tstamp_sec,
1051 		.trigger_tstamp_nsec = status64.trigger_tstamp_nsec,
1052 		.tstamp_sec = status64.tstamp_sec,
1053 		.tstamp_nsec = status64.tstamp_nsec,
1054 		.appl_ptr = status64.appl_ptr,
1055 		.hw_ptr = status64.hw_ptr,
1056 		.delay = status64.delay,
1057 		.avail = status64.avail,
1058 		.avail_max = status64.avail_max,
1059 		.overrange = status64.overrange,
1060 		.suspended_state = status64.suspended_state,
1061 		.audio_tstamp_data = status64.audio_tstamp_data,
1062 		.audio_tstamp_sec = status64.audio_tstamp_sec,
1063 		.audio_tstamp_nsec = status64.audio_tstamp_nsec,
1064 		.driver_tstamp_sec = status64.audio_tstamp_sec,
1065 		.driver_tstamp_nsec = status64.audio_tstamp_nsec,
1066 		.audio_tstamp_accuracy = status64.audio_tstamp_accuracy,
1067 	};
1068 
1069 	if (copy_to_user(_status, &status32, sizeof(status32)))
1070 		return -EFAULT;
1071 
1072 	return 0;
1073 }
1074 
1075 static int snd_pcm_channel_info(struct snd_pcm_substream *substream,
1076 				struct snd_pcm_channel_info * info)
1077 {
1078 	struct snd_pcm_runtime *runtime;
1079 	unsigned int channel;
1080 
1081 	channel = info->channel;
1082 	runtime = substream->runtime;
1083 	snd_pcm_stream_lock_irq(substream);
1084 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
1085 		snd_pcm_stream_unlock_irq(substream);
1086 		return -EBADFD;
1087 	}
1088 	snd_pcm_stream_unlock_irq(substream);
1089 	if (channel >= runtime->channels)
1090 		return -EINVAL;
1091 	memset(info, 0, sizeof(*info));
1092 	info->channel = channel;
1093 	return snd_pcm_ops_ioctl(substream, SNDRV_PCM_IOCTL1_CHANNEL_INFO, info);
1094 }
1095 
1096 static int snd_pcm_channel_info_user(struct snd_pcm_substream *substream,
1097 				     struct snd_pcm_channel_info __user * _info)
1098 {
1099 	struct snd_pcm_channel_info info;
1100 	int res;
1101 
1102 	if (copy_from_user(&info, _info, sizeof(info)))
1103 		return -EFAULT;
1104 	res = snd_pcm_channel_info(substream, &info);
1105 	if (res < 0)
1106 		return res;
1107 	if (copy_to_user(_info, &info, sizeof(info)))
1108 		return -EFAULT;
1109 	return 0;
1110 }
1111 
1112 static void snd_pcm_trigger_tstamp(struct snd_pcm_substream *substream)
1113 {
1114 	struct snd_pcm_runtime *runtime = substream->runtime;
1115 	if (runtime->trigger_master == NULL)
1116 		return;
1117 	if (runtime->trigger_master == substream) {
1118 		if (!runtime->trigger_tstamp_latched)
1119 			snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
1120 	} else {
1121 		snd_pcm_trigger_tstamp(runtime->trigger_master);
1122 		runtime->trigger_tstamp = runtime->trigger_master->runtime->trigger_tstamp;
1123 	}
1124 	runtime->trigger_master = NULL;
1125 }
1126 
1127 #define ACTION_ARG_IGNORE	(__force snd_pcm_state_t)0
1128 
1129 struct action_ops {
1130 	int (*pre_action)(struct snd_pcm_substream *substream,
1131 			  snd_pcm_state_t state);
1132 	int (*do_action)(struct snd_pcm_substream *substream,
1133 			 snd_pcm_state_t state);
1134 	void (*undo_action)(struct snd_pcm_substream *substream,
1135 			    snd_pcm_state_t state);
1136 	void (*post_action)(struct snd_pcm_substream *substream,
1137 			    snd_pcm_state_t state);
1138 };
1139 
1140 /*
1141  *  this functions is core for handling of linked stream
1142  *  Note: the stream state might be changed also on failure
1143  *  Note2: call with calling stream lock + link lock
1144  */
1145 static int snd_pcm_action_group(const struct action_ops *ops,
1146 				struct snd_pcm_substream *substream,
1147 				snd_pcm_state_t state,
1148 				bool do_lock)
1149 {
1150 	struct snd_pcm_substream *s = NULL;
1151 	struct snd_pcm_substream *s1;
1152 	int res = 0, depth = 1;
1153 
1154 	snd_pcm_group_for_each_entry(s, substream) {
1155 		if (do_lock && s != substream) {
1156 			if (s->pcm->nonatomic)
1157 				mutex_lock_nested(&s->self_group.mutex, depth);
1158 			else
1159 				spin_lock_nested(&s->self_group.lock, depth);
1160 			depth++;
1161 		}
1162 		res = ops->pre_action(s, state);
1163 		if (res < 0)
1164 			goto _unlock;
1165 	}
1166 	snd_pcm_group_for_each_entry(s, substream) {
1167 		res = ops->do_action(s, state);
1168 		if (res < 0) {
1169 			if (ops->undo_action) {
1170 				snd_pcm_group_for_each_entry(s1, substream) {
1171 					if (s1 == s) /* failed stream */
1172 						break;
1173 					ops->undo_action(s1, state);
1174 				}
1175 			}
1176 			s = NULL; /* unlock all */
1177 			goto _unlock;
1178 		}
1179 	}
1180 	snd_pcm_group_for_each_entry(s, substream) {
1181 		ops->post_action(s, state);
1182 	}
1183  _unlock:
1184 	if (do_lock) {
1185 		/* unlock streams */
1186 		snd_pcm_group_for_each_entry(s1, substream) {
1187 			if (s1 != substream) {
1188 				if (s1->pcm->nonatomic)
1189 					mutex_unlock(&s1->self_group.mutex);
1190 				else
1191 					spin_unlock(&s1->self_group.lock);
1192 			}
1193 			if (s1 == s)	/* end */
1194 				break;
1195 		}
1196 	}
1197 	return res;
1198 }
1199 
1200 /*
1201  *  Note: call with stream lock
1202  */
1203 static int snd_pcm_action_single(const struct action_ops *ops,
1204 				 struct snd_pcm_substream *substream,
1205 				 snd_pcm_state_t state)
1206 {
1207 	int res;
1208 
1209 	res = ops->pre_action(substream, state);
1210 	if (res < 0)
1211 		return res;
1212 	res = ops->do_action(substream, state);
1213 	if (res == 0)
1214 		ops->post_action(substream, state);
1215 	else if (ops->undo_action)
1216 		ops->undo_action(substream, state);
1217 	return res;
1218 }
1219 
1220 static void snd_pcm_group_assign(struct snd_pcm_substream *substream,
1221 				 struct snd_pcm_group *new_group)
1222 {
1223 	substream->group = new_group;
1224 	list_move(&substream->link_list, &new_group->substreams);
1225 }
1226 
1227 /*
1228  * Unref and unlock the group, but keep the stream lock;
1229  * when the group becomes empty and no longer referred, destroy itself
1230  */
1231 static void snd_pcm_group_unref(struct snd_pcm_group *group,
1232 				struct snd_pcm_substream *substream)
1233 {
1234 	bool do_free;
1235 
1236 	if (!group)
1237 		return;
1238 	do_free = refcount_dec_and_test(&group->refs);
1239 	snd_pcm_group_unlock(group, substream->pcm->nonatomic);
1240 	if (do_free)
1241 		kfree(group);
1242 }
1243 
1244 /*
1245  * Lock the group inside a stream lock and reference it;
1246  * return the locked group object, or NULL if not linked
1247  */
1248 static struct snd_pcm_group *
1249 snd_pcm_stream_group_ref(struct snd_pcm_substream *substream)
1250 {
1251 	bool nonatomic = substream->pcm->nonatomic;
1252 	struct snd_pcm_group *group;
1253 	bool trylock;
1254 
1255 	for (;;) {
1256 		if (!snd_pcm_stream_linked(substream))
1257 			return NULL;
1258 		group = substream->group;
1259 		/* block freeing the group object */
1260 		refcount_inc(&group->refs);
1261 
1262 		trylock = nonatomic ? mutex_trylock(&group->mutex) :
1263 			spin_trylock(&group->lock);
1264 		if (trylock)
1265 			break; /* OK */
1266 
1267 		/* re-lock for avoiding ABBA deadlock */
1268 		snd_pcm_stream_unlock(substream);
1269 		snd_pcm_group_lock(group, nonatomic);
1270 		snd_pcm_stream_lock(substream);
1271 
1272 		/* check the group again; the above opens a small race window */
1273 		if (substream->group == group)
1274 			break; /* OK */
1275 		/* group changed, try again */
1276 		snd_pcm_group_unref(group, substream);
1277 	}
1278 	return group;
1279 }
1280 
1281 /*
1282  *  Note: call with stream lock
1283  */
1284 static int snd_pcm_action(const struct action_ops *ops,
1285 			  struct snd_pcm_substream *substream,
1286 			  snd_pcm_state_t state)
1287 {
1288 	struct snd_pcm_group *group;
1289 	int res;
1290 
1291 	group = snd_pcm_stream_group_ref(substream);
1292 	if (group)
1293 		res = snd_pcm_action_group(ops, substream, state, true);
1294 	else
1295 		res = snd_pcm_action_single(ops, substream, state);
1296 	snd_pcm_group_unref(group, substream);
1297 	return res;
1298 }
1299 
1300 /*
1301  *  Note: don't use any locks before
1302  */
1303 static int snd_pcm_action_lock_irq(const struct action_ops *ops,
1304 				   struct snd_pcm_substream *substream,
1305 				   snd_pcm_state_t state)
1306 {
1307 	int res;
1308 
1309 	snd_pcm_stream_lock_irq(substream);
1310 	res = snd_pcm_action(ops, substream, state);
1311 	snd_pcm_stream_unlock_irq(substream);
1312 	return res;
1313 }
1314 
1315 /*
1316  */
1317 static int snd_pcm_action_nonatomic(const struct action_ops *ops,
1318 				    struct snd_pcm_substream *substream,
1319 				    snd_pcm_state_t state)
1320 {
1321 	int res;
1322 
1323 	/* Guarantee the group members won't change during non-atomic action */
1324 	down_read(&snd_pcm_link_rwsem);
1325 	if (snd_pcm_stream_linked(substream))
1326 		res = snd_pcm_action_group(ops, substream, state, false);
1327 	else
1328 		res = snd_pcm_action_single(ops, substream, state);
1329 	up_read(&snd_pcm_link_rwsem);
1330 	return res;
1331 }
1332 
1333 /*
1334  * start callbacks
1335  */
1336 static int snd_pcm_pre_start(struct snd_pcm_substream *substream,
1337 			     snd_pcm_state_t state)
1338 {
1339 	struct snd_pcm_runtime *runtime = substream->runtime;
1340 	if (runtime->status->state != SNDRV_PCM_STATE_PREPARED)
1341 		return -EBADFD;
1342 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
1343 	    !snd_pcm_playback_data(substream))
1344 		return -EPIPE;
1345 	runtime->trigger_tstamp_latched = false;
1346 	runtime->trigger_master = substream;
1347 	return 0;
1348 }
1349 
1350 static int snd_pcm_do_start(struct snd_pcm_substream *substream,
1351 			    snd_pcm_state_t state)
1352 {
1353 	if (substream->runtime->trigger_master != substream)
1354 		return 0;
1355 	return substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_START);
1356 }
1357 
1358 static void snd_pcm_undo_start(struct snd_pcm_substream *substream,
1359 			       snd_pcm_state_t state)
1360 {
1361 	if (substream->runtime->trigger_master == substream)
1362 		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_STOP);
1363 }
1364 
1365 static void snd_pcm_post_start(struct snd_pcm_substream *substream,
1366 			       snd_pcm_state_t state)
1367 {
1368 	struct snd_pcm_runtime *runtime = substream->runtime;
1369 	snd_pcm_trigger_tstamp(substream);
1370 	runtime->hw_ptr_jiffies = jiffies;
1371 	runtime->hw_ptr_buffer_jiffies = (runtime->buffer_size * HZ) /
1372 							    runtime->rate;
1373 	runtime->status->state = state;
1374 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
1375 	    runtime->silence_size > 0)
1376 		snd_pcm_playback_silence(substream, ULONG_MAX);
1377 	snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MSTART);
1378 }
1379 
1380 static const struct action_ops snd_pcm_action_start = {
1381 	.pre_action = snd_pcm_pre_start,
1382 	.do_action = snd_pcm_do_start,
1383 	.undo_action = snd_pcm_undo_start,
1384 	.post_action = snd_pcm_post_start
1385 };
1386 
1387 /**
1388  * snd_pcm_start - start all linked streams
1389  * @substream: the PCM substream instance
1390  *
1391  * Return: Zero if successful, or a negative error code.
1392  * The stream lock must be acquired before calling this function.
1393  */
1394 int snd_pcm_start(struct snd_pcm_substream *substream)
1395 {
1396 	return snd_pcm_action(&snd_pcm_action_start, substream,
1397 			      SNDRV_PCM_STATE_RUNNING);
1398 }
1399 
1400 /* take the stream lock and start the streams */
1401 static int snd_pcm_start_lock_irq(struct snd_pcm_substream *substream)
1402 {
1403 	return snd_pcm_action_lock_irq(&snd_pcm_action_start, substream,
1404 				       SNDRV_PCM_STATE_RUNNING);
1405 }
1406 
1407 /*
1408  * stop callbacks
1409  */
1410 static int snd_pcm_pre_stop(struct snd_pcm_substream *substream,
1411 			    snd_pcm_state_t state)
1412 {
1413 	struct snd_pcm_runtime *runtime = substream->runtime;
1414 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1415 		return -EBADFD;
1416 	runtime->trigger_master = substream;
1417 	return 0;
1418 }
1419 
1420 static int snd_pcm_do_stop(struct snd_pcm_substream *substream,
1421 			   snd_pcm_state_t state)
1422 {
1423 	if (substream->runtime->trigger_master == substream &&
1424 	    snd_pcm_running(substream)) {
1425 		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_STOP);
1426 		substream->runtime->stop_operating = true;
1427 	}
1428 	return 0; /* unconditonally stop all substreams */
1429 }
1430 
1431 static void snd_pcm_post_stop(struct snd_pcm_substream *substream,
1432 			      snd_pcm_state_t state)
1433 {
1434 	struct snd_pcm_runtime *runtime = substream->runtime;
1435 	if (runtime->status->state != state) {
1436 		snd_pcm_trigger_tstamp(substream);
1437 		runtime->status->state = state;
1438 		snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MSTOP);
1439 	}
1440 	wake_up(&runtime->sleep);
1441 	wake_up(&runtime->tsleep);
1442 }
1443 
1444 static const struct action_ops snd_pcm_action_stop = {
1445 	.pre_action = snd_pcm_pre_stop,
1446 	.do_action = snd_pcm_do_stop,
1447 	.post_action = snd_pcm_post_stop
1448 };
1449 
1450 /**
1451  * snd_pcm_stop - try to stop all running streams in the substream group
1452  * @substream: the PCM substream instance
1453  * @state: PCM state after stopping the stream
1454  *
1455  * The state of each stream is then changed to the given state unconditionally.
1456  *
1457  * Return: Zero if successful, or a negative error code.
1458  */
1459 int snd_pcm_stop(struct snd_pcm_substream *substream, snd_pcm_state_t state)
1460 {
1461 	return snd_pcm_action(&snd_pcm_action_stop, substream, state);
1462 }
1463 EXPORT_SYMBOL(snd_pcm_stop);
1464 
1465 /**
1466  * snd_pcm_drain_done - stop the DMA only when the given stream is playback
1467  * @substream: the PCM substream
1468  *
1469  * After stopping, the state is changed to SETUP.
1470  * Unlike snd_pcm_stop(), this affects only the given stream.
1471  *
1472  * Return: Zero if succesful, or a negative error code.
1473  */
1474 int snd_pcm_drain_done(struct snd_pcm_substream *substream)
1475 {
1476 	return snd_pcm_action_single(&snd_pcm_action_stop, substream,
1477 				     SNDRV_PCM_STATE_SETUP);
1478 }
1479 
1480 /**
1481  * snd_pcm_stop_xrun - stop the running streams as XRUN
1482  * @substream: the PCM substream instance
1483  *
1484  * This stops the given running substream (and all linked substreams) as XRUN.
1485  * Unlike snd_pcm_stop(), this function takes the substream lock by itself.
1486  *
1487  * Return: Zero if successful, or a negative error code.
1488  */
1489 int snd_pcm_stop_xrun(struct snd_pcm_substream *substream)
1490 {
1491 	unsigned long flags;
1492 
1493 	snd_pcm_stream_lock_irqsave(substream, flags);
1494 	if (substream->runtime && snd_pcm_running(substream))
1495 		__snd_pcm_xrun(substream);
1496 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1497 	return 0;
1498 }
1499 EXPORT_SYMBOL_GPL(snd_pcm_stop_xrun);
1500 
1501 /*
1502  * pause callbacks: pass boolean (to start pause or resume) as state argument
1503  */
1504 #define pause_pushed(state)	(__force bool)(state)
1505 
1506 static int snd_pcm_pre_pause(struct snd_pcm_substream *substream,
1507 			     snd_pcm_state_t state)
1508 {
1509 	struct snd_pcm_runtime *runtime = substream->runtime;
1510 	if (!(runtime->info & SNDRV_PCM_INFO_PAUSE))
1511 		return -ENOSYS;
1512 	if (pause_pushed(state)) {
1513 		if (runtime->status->state != SNDRV_PCM_STATE_RUNNING)
1514 			return -EBADFD;
1515 	} else if (runtime->status->state != SNDRV_PCM_STATE_PAUSED)
1516 		return -EBADFD;
1517 	runtime->trigger_master = substream;
1518 	return 0;
1519 }
1520 
1521 static int snd_pcm_do_pause(struct snd_pcm_substream *substream,
1522 			    snd_pcm_state_t state)
1523 {
1524 	if (substream->runtime->trigger_master != substream)
1525 		return 0;
1526 	/* some drivers might use hw_ptr to recover from the pause -
1527 	   update the hw_ptr now */
1528 	if (pause_pushed(state))
1529 		snd_pcm_update_hw_ptr(substream);
1530 	/* The jiffies check in snd_pcm_update_hw_ptr*() is done by
1531 	 * a delta between the current jiffies, this gives a large enough
1532 	 * delta, effectively to skip the check once.
1533 	 */
1534 	substream->runtime->hw_ptr_jiffies = jiffies - HZ * 1000;
1535 	return substream->ops->trigger(substream,
1536 				       pause_pushed(state) ?
1537 				       SNDRV_PCM_TRIGGER_PAUSE_PUSH :
1538 				       SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
1539 }
1540 
1541 static void snd_pcm_undo_pause(struct snd_pcm_substream *substream,
1542 			       snd_pcm_state_t state)
1543 {
1544 	if (substream->runtime->trigger_master == substream)
1545 		substream->ops->trigger(substream,
1546 					pause_pushed(state) ?
1547 					SNDRV_PCM_TRIGGER_PAUSE_RELEASE :
1548 					SNDRV_PCM_TRIGGER_PAUSE_PUSH);
1549 }
1550 
1551 static void snd_pcm_post_pause(struct snd_pcm_substream *substream,
1552 			       snd_pcm_state_t state)
1553 {
1554 	struct snd_pcm_runtime *runtime = substream->runtime;
1555 	snd_pcm_trigger_tstamp(substream);
1556 	if (pause_pushed(state)) {
1557 		runtime->status->state = SNDRV_PCM_STATE_PAUSED;
1558 		snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MPAUSE);
1559 		wake_up(&runtime->sleep);
1560 		wake_up(&runtime->tsleep);
1561 	} else {
1562 		runtime->status->state = SNDRV_PCM_STATE_RUNNING;
1563 		snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MCONTINUE);
1564 	}
1565 }
1566 
1567 static const struct action_ops snd_pcm_action_pause = {
1568 	.pre_action = snd_pcm_pre_pause,
1569 	.do_action = snd_pcm_do_pause,
1570 	.undo_action = snd_pcm_undo_pause,
1571 	.post_action = snd_pcm_post_pause
1572 };
1573 
1574 /*
1575  * Push/release the pause for all linked streams.
1576  */
1577 static int snd_pcm_pause(struct snd_pcm_substream *substream, bool push)
1578 {
1579 	return snd_pcm_action(&snd_pcm_action_pause, substream,
1580 			      (__force snd_pcm_state_t)push);
1581 }
1582 
1583 static int snd_pcm_pause_lock_irq(struct snd_pcm_substream *substream,
1584 				  bool push)
1585 {
1586 	return snd_pcm_action_lock_irq(&snd_pcm_action_pause, substream,
1587 				       (__force snd_pcm_state_t)push);
1588 }
1589 
1590 #ifdef CONFIG_PM
1591 /* suspend callback: state argument ignored */
1592 
1593 static int snd_pcm_pre_suspend(struct snd_pcm_substream *substream,
1594 			       snd_pcm_state_t state)
1595 {
1596 	struct snd_pcm_runtime *runtime = substream->runtime;
1597 	switch (runtime->status->state) {
1598 	case SNDRV_PCM_STATE_SUSPENDED:
1599 		return -EBUSY;
1600 	/* unresumable PCM state; return -EBUSY for skipping suspend */
1601 	case SNDRV_PCM_STATE_OPEN:
1602 	case SNDRV_PCM_STATE_SETUP:
1603 	case SNDRV_PCM_STATE_DISCONNECTED:
1604 		return -EBUSY;
1605 	}
1606 	runtime->trigger_master = substream;
1607 	return 0;
1608 }
1609 
1610 static int snd_pcm_do_suspend(struct snd_pcm_substream *substream,
1611 			      snd_pcm_state_t state)
1612 {
1613 	struct snd_pcm_runtime *runtime = substream->runtime;
1614 	if (runtime->trigger_master != substream)
1615 		return 0;
1616 	if (! snd_pcm_running(substream))
1617 		return 0;
1618 	substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_SUSPEND);
1619 	runtime->stop_operating = true;
1620 	return 0; /* suspend unconditionally */
1621 }
1622 
1623 static void snd_pcm_post_suspend(struct snd_pcm_substream *substream,
1624 				 snd_pcm_state_t state)
1625 {
1626 	struct snd_pcm_runtime *runtime = substream->runtime;
1627 	snd_pcm_trigger_tstamp(substream);
1628 	runtime->status->suspended_state = runtime->status->state;
1629 	runtime->status->state = SNDRV_PCM_STATE_SUSPENDED;
1630 	snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MSUSPEND);
1631 	wake_up(&runtime->sleep);
1632 	wake_up(&runtime->tsleep);
1633 }
1634 
1635 static const struct action_ops snd_pcm_action_suspend = {
1636 	.pre_action = snd_pcm_pre_suspend,
1637 	.do_action = snd_pcm_do_suspend,
1638 	.post_action = snd_pcm_post_suspend
1639 };
1640 
1641 /*
1642  * snd_pcm_suspend - trigger SUSPEND to all linked streams
1643  * @substream: the PCM substream
1644  *
1645  * After this call, all streams are changed to SUSPENDED state.
1646  *
1647  * Return: Zero if successful, or a negative error code.
1648  */
1649 static int snd_pcm_suspend(struct snd_pcm_substream *substream)
1650 {
1651 	int err;
1652 	unsigned long flags;
1653 
1654 	snd_pcm_stream_lock_irqsave(substream, flags);
1655 	err = snd_pcm_action(&snd_pcm_action_suspend, substream,
1656 			     ACTION_ARG_IGNORE);
1657 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1658 	return err;
1659 }
1660 
1661 /**
1662  * snd_pcm_suspend_all - trigger SUSPEND to all substreams in the given pcm
1663  * @pcm: the PCM instance
1664  *
1665  * After this call, all streams are changed to SUSPENDED state.
1666  *
1667  * Return: Zero if successful (or @pcm is %NULL), or a negative error code.
1668  */
1669 int snd_pcm_suspend_all(struct snd_pcm *pcm)
1670 {
1671 	struct snd_pcm_substream *substream;
1672 	int stream, err = 0;
1673 
1674 	if (! pcm)
1675 		return 0;
1676 
1677 	for_each_pcm_substream(pcm, stream, substream) {
1678 		/* FIXME: the open/close code should lock this as well */
1679 		if (!substream->runtime)
1680 			continue;
1681 
1682 		/*
1683 		 * Skip BE dai link PCM's that are internal and may
1684 		 * not have their substream ops set.
1685 		 */
1686 		if (!substream->ops)
1687 			continue;
1688 
1689 		err = snd_pcm_suspend(substream);
1690 		if (err < 0 && err != -EBUSY)
1691 			return err;
1692 	}
1693 
1694 	for_each_pcm_substream(pcm, stream, substream)
1695 		snd_pcm_sync_stop(substream, false);
1696 
1697 	return 0;
1698 }
1699 EXPORT_SYMBOL(snd_pcm_suspend_all);
1700 
1701 /* resume callbacks: state argument ignored */
1702 
1703 static int snd_pcm_pre_resume(struct snd_pcm_substream *substream,
1704 			      snd_pcm_state_t state)
1705 {
1706 	struct snd_pcm_runtime *runtime = substream->runtime;
1707 	if (!(runtime->info & SNDRV_PCM_INFO_RESUME))
1708 		return -ENOSYS;
1709 	runtime->trigger_master = substream;
1710 	return 0;
1711 }
1712 
1713 static int snd_pcm_do_resume(struct snd_pcm_substream *substream,
1714 			     snd_pcm_state_t state)
1715 {
1716 	struct snd_pcm_runtime *runtime = substream->runtime;
1717 	if (runtime->trigger_master != substream)
1718 		return 0;
1719 	/* DMA not running previously? */
1720 	if (runtime->status->suspended_state != SNDRV_PCM_STATE_RUNNING &&
1721 	    (runtime->status->suspended_state != SNDRV_PCM_STATE_DRAINING ||
1722 	     substream->stream != SNDRV_PCM_STREAM_PLAYBACK))
1723 		return 0;
1724 	return substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_RESUME);
1725 }
1726 
1727 static void snd_pcm_undo_resume(struct snd_pcm_substream *substream,
1728 				snd_pcm_state_t state)
1729 {
1730 	if (substream->runtime->trigger_master == substream &&
1731 	    snd_pcm_running(substream))
1732 		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_SUSPEND);
1733 }
1734 
1735 static void snd_pcm_post_resume(struct snd_pcm_substream *substream,
1736 				snd_pcm_state_t state)
1737 {
1738 	struct snd_pcm_runtime *runtime = substream->runtime;
1739 	snd_pcm_trigger_tstamp(substream);
1740 	runtime->status->state = runtime->status->suspended_state;
1741 	snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MRESUME);
1742 }
1743 
1744 static const struct action_ops snd_pcm_action_resume = {
1745 	.pre_action = snd_pcm_pre_resume,
1746 	.do_action = snd_pcm_do_resume,
1747 	.undo_action = snd_pcm_undo_resume,
1748 	.post_action = snd_pcm_post_resume
1749 };
1750 
1751 static int snd_pcm_resume(struct snd_pcm_substream *substream)
1752 {
1753 	return snd_pcm_action_lock_irq(&snd_pcm_action_resume, substream,
1754 				       ACTION_ARG_IGNORE);
1755 }
1756 
1757 #else
1758 
1759 static int snd_pcm_resume(struct snd_pcm_substream *substream)
1760 {
1761 	return -ENOSYS;
1762 }
1763 
1764 #endif /* CONFIG_PM */
1765 
1766 /*
1767  * xrun ioctl
1768  *
1769  * Change the RUNNING stream(s) to XRUN state.
1770  */
1771 static int snd_pcm_xrun(struct snd_pcm_substream *substream)
1772 {
1773 	struct snd_pcm_runtime *runtime = substream->runtime;
1774 	int result;
1775 
1776 	snd_pcm_stream_lock_irq(substream);
1777 	switch (runtime->status->state) {
1778 	case SNDRV_PCM_STATE_XRUN:
1779 		result = 0;	/* already there */
1780 		break;
1781 	case SNDRV_PCM_STATE_RUNNING:
1782 		__snd_pcm_xrun(substream);
1783 		result = 0;
1784 		break;
1785 	default:
1786 		result = -EBADFD;
1787 	}
1788 	snd_pcm_stream_unlock_irq(substream);
1789 	return result;
1790 }
1791 
1792 /*
1793  * reset ioctl
1794  */
1795 /* reset callbacks:  state argument ignored */
1796 static int snd_pcm_pre_reset(struct snd_pcm_substream *substream,
1797 			     snd_pcm_state_t state)
1798 {
1799 	struct snd_pcm_runtime *runtime = substream->runtime;
1800 	switch (runtime->status->state) {
1801 	case SNDRV_PCM_STATE_RUNNING:
1802 	case SNDRV_PCM_STATE_PREPARED:
1803 	case SNDRV_PCM_STATE_PAUSED:
1804 	case SNDRV_PCM_STATE_SUSPENDED:
1805 		return 0;
1806 	default:
1807 		return -EBADFD;
1808 	}
1809 }
1810 
1811 static int snd_pcm_do_reset(struct snd_pcm_substream *substream,
1812 			    snd_pcm_state_t state)
1813 {
1814 	struct snd_pcm_runtime *runtime = substream->runtime;
1815 	int err = snd_pcm_ops_ioctl(substream, SNDRV_PCM_IOCTL1_RESET, NULL);
1816 	if (err < 0)
1817 		return err;
1818 	runtime->hw_ptr_base = 0;
1819 	runtime->hw_ptr_interrupt = runtime->status->hw_ptr -
1820 		runtime->status->hw_ptr % runtime->period_size;
1821 	runtime->silence_start = runtime->status->hw_ptr;
1822 	runtime->silence_filled = 0;
1823 	return 0;
1824 }
1825 
1826 static void snd_pcm_post_reset(struct snd_pcm_substream *substream,
1827 			       snd_pcm_state_t state)
1828 {
1829 	struct snd_pcm_runtime *runtime = substream->runtime;
1830 	runtime->control->appl_ptr = runtime->status->hw_ptr;
1831 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
1832 	    runtime->silence_size > 0)
1833 		snd_pcm_playback_silence(substream, ULONG_MAX);
1834 }
1835 
1836 static const struct action_ops snd_pcm_action_reset = {
1837 	.pre_action = snd_pcm_pre_reset,
1838 	.do_action = snd_pcm_do_reset,
1839 	.post_action = snd_pcm_post_reset
1840 };
1841 
1842 static int snd_pcm_reset(struct snd_pcm_substream *substream)
1843 {
1844 	return snd_pcm_action_nonatomic(&snd_pcm_action_reset, substream,
1845 					ACTION_ARG_IGNORE);
1846 }
1847 
1848 /*
1849  * prepare ioctl
1850  */
1851 /* pass f_flags as state argument */
1852 static int snd_pcm_pre_prepare(struct snd_pcm_substream *substream,
1853 			       snd_pcm_state_t state)
1854 {
1855 	struct snd_pcm_runtime *runtime = substream->runtime;
1856 	int f_flags = (__force int)state;
1857 
1858 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN ||
1859 	    runtime->status->state == SNDRV_PCM_STATE_DISCONNECTED)
1860 		return -EBADFD;
1861 	if (snd_pcm_running(substream))
1862 		return -EBUSY;
1863 	substream->f_flags = f_flags;
1864 	return 0;
1865 }
1866 
1867 static int snd_pcm_do_prepare(struct snd_pcm_substream *substream,
1868 			      snd_pcm_state_t state)
1869 {
1870 	int err;
1871 	snd_pcm_sync_stop(substream, true);
1872 	err = substream->ops->prepare(substream);
1873 	if (err < 0)
1874 		return err;
1875 	return snd_pcm_do_reset(substream, state);
1876 }
1877 
1878 static void snd_pcm_post_prepare(struct snd_pcm_substream *substream,
1879 				 snd_pcm_state_t state)
1880 {
1881 	struct snd_pcm_runtime *runtime = substream->runtime;
1882 	runtime->control->appl_ptr = runtime->status->hw_ptr;
1883 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_PREPARED);
1884 }
1885 
1886 static const struct action_ops snd_pcm_action_prepare = {
1887 	.pre_action = snd_pcm_pre_prepare,
1888 	.do_action = snd_pcm_do_prepare,
1889 	.post_action = snd_pcm_post_prepare
1890 };
1891 
1892 /**
1893  * snd_pcm_prepare - prepare the PCM substream to be triggerable
1894  * @substream: the PCM substream instance
1895  * @file: file to refer f_flags
1896  *
1897  * Return: Zero if successful, or a negative error code.
1898  */
1899 static int snd_pcm_prepare(struct snd_pcm_substream *substream,
1900 			   struct file *file)
1901 {
1902 	int f_flags;
1903 
1904 	if (file)
1905 		f_flags = file->f_flags;
1906 	else
1907 		f_flags = substream->f_flags;
1908 
1909 	snd_pcm_stream_lock_irq(substream);
1910 	switch (substream->runtime->status->state) {
1911 	case SNDRV_PCM_STATE_PAUSED:
1912 		snd_pcm_pause(substream, false);
1913 		fallthrough;
1914 	case SNDRV_PCM_STATE_SUSPENDED:
1915 		snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
1916 		break;
1917 	}
1918 	snd_pcm_stream_unlock_irq(substream);
1919 
1920 	return snd_pcm_action_nonatomic(&snd_pcm_action_prepare,
1921 					substream,
1922 					(__force snd_pcm_state_t)f_flags);
1923 }
1924 
1925 /*
1926  * drain ioctl
1927  */
1928 
1929 /* drain init callbacks: state argument ignored */
1930 static int snd_pcm_pre_drain_init(struct snd_pcm_substream *substream,
1931 				  snd_pcm_state_t state)
1932 {
1933 	struct snd_pcm_runtime *runtime = substream->runtime;
1934 	switch (runtime->status->state) {
1935 	case SNDRV_PCM_STATE_OPEN:
1936 	case SNDRV_PCM_STATE_DISCONNECTED:
1937 	case SNDRV_PCM_STATE_SUSPENDED:
1938 		return -EBADFD;
1939 	}
1940 	runtime->trigger_master = substream;
1941 	return 0;
1942 }
1943 
1944 static int snd_pcm_do_drain_init(struct snd_pcm_substream *substream,
1945 				 snd_pcm_state_t state)
1946 {
1947 	struct snd_pcm_runtime *runtime = substream->runtime;
1948 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
1949 		switch (runtime->status->state) {
1950 		case SNDRV_PCM_STATE_PREPARED:
1951 			/* start playback stream if possible */
1952 			if (! snd_pcm_playback_empty(substream)) {
1953 				snd_pcm_do_start(substream, SNDRV_PCM_STATE_DRAINING);
1954 				snd_pcm_post_start(substream, SNDRV_PCM_STATE_DRAINING);
1955 			} else {
1956 				runtime->status->state = SNDRV_PCM_STATE_SETUP;
1957 			}
1958 			break;
1959 		case SNDRV_PCM_STATE_RUNNING:
1960 			runtime->status->state = SNDRV_PCM_STATE_DRAINING;
1961 			break;
1962 		case SNDRV_PCM_STATE_XRUN:
1963 			runtime->status->state = SNDRV_PCM_STATE_SETUP;
1964 			break;
1965 		default:
1966 			break;
1967 		}
1968 	} else {
1969 		/* stop running stream */
1970 		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING) {
1971 			snd_pcm_state_t new_state;
1972 
1973 			new_state = snd_pcm_capture_avail(runtime) > 0 ?
1974 				SNDRV_PCM_STATE_DRAINING : SNDRV_PCM_STATE_SETUP;
1975 			snd_pcm_do_stop(substream, new_state);
1976 			snd_pcm_post_stop(substream, new_state);
1977 		}
1978 	}
1979 
1980 	if (runtime->status->state == SNDRV_PCM_STATE_DRAINING &&
1981 	    runtime->trigger_master == substream &&
1982 	    (runtime->hw.info & SNDRV_PCM_INFO_DRAIN_TRIGGER))
1983 		return substream->ops->trigger(substream,
1984 					       SNDRV_PCM_TRIGGER_DRAIN);
1985 
1986 	return 0;
1987 }
1988 
1989 static void snd_pcm_post_drain_init(struct snd_pcm_substream *substream,
1990 				    snd_pcm_state_t state)
1991 {
1992 }
1993 
1994 static const struct action_ops snd_pcm_action_drain_init = {
1995 	.pre_action = snd_pcm_pre_drain_init,
1996 	.do_action = snd_pcm_do_drain_init,
1997 	.post_action = snd_pcm_post_drain_init
1998 };
1999 
2000 /*
2001  * Drain the stream(s).
2002  * When the substream is linked, sync until the draining of all playback streams
2003  * is finished.
2004  * After this call, all streams are supposed to be either SETUP or DRAINING
2005  * (capture only) state.
2006  */
2007 static int snd_pcm_drain(struct snd_pcm_substream *substream,
2008 			 struct file *file)
2009 {
2010 	struct snd_card *card;
2011 	struct snd_pcm_runtime *runtime;
2012 	struct snd_pcm_substream *s;
2013 	struct snd_pcm_group *group;
2014 	wait_queue_entry_t wait;
2015 	int result = 0;
2016 	int nonblock = 0;
2017 
2018 	card = substream->pcm->card;
2019 	runtime = substream->runtime;
2020 
2021 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2022 		return -EBADFD;
2023 
2024 	if (file) {
2025 		if (file->f_flags & O_NONBLOCK)
2026 			nonblock = 1;
2027 	} else if (substream->f_flags & O_NONBLOCK)
2028 		nonblock = 1;
2029 
2030 	snd_pcm_stream_lock_irq(substream);
2031 	/* resume pause */
2032 	if (runtime->status->state == SNDRV_PCM_STATE_PAUSED)
2033 		snd_pcm_pause(substream, false);
2034 
2035 	/* pre-start/stop - all running streams are changed to DRAINING state */
2036 	result = snd_pcm_action(&snd_pcm_action_drain_init, substream,
2037 				ACTION_ARG_IGNORE);
2038 	if (result < 0)
2039 		goto unlock;
2040 	/* in non-blocking, we don't wait in ioctl but let caller poll */
2041 	if (nonblock) {
2042 		result = -EAGAIN;
2043 		goto unlock;
2044 	}
2045 
2046 	for (;;) {
2047 		long tout;
2048 		struct snd_pcm_runtime *to_check;
2049 		if (signal_pending(current)) {
2050 			result = -ERESTARTSYS;
2051 			break;
2052 		}
2053 		/* find a substream to drain */
2054 		to_check = NULL;
2055 		group = snd_pcm_stream_group_ref(substream);
2056 		snd_pcm_group_for_each_entry(s, substream) {
2057 			if (s->stream != SNDRV_PCM_STREAM_PLAYBACK)
2058 				continue;
2059 			runtime = s->runtime;
2060 			if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
2061 				to_check = runtime;
2062 				break;
2063 			}
2064 		}
2065 		snd_pcm_group_unref(group, substream);
2066 		if (!to_check)
2067 			break; /* all drained */
2068 		init_waitqueue_entry(&wait, current);
2069 		set_current_state(TASK_INTERRUPTIBLE);
2070 		add_wait_queue(&to_check->sleep, &wait);
2071 		snd_pcm_stream_unlock_irq(substream);
2072 		if (runtime->no_period_wakeup)
2073 			tout = MAX_SCHEDULE_TIMEOUT;
2074 		else {
2075 			tout = 10;
2076 			if (runtime->rate) {
2077 				long t = runtime->period_size * 2 / runtime->rate;
2078 				tout = max(t, tout);
2079 			}
2080 			tout = msecs_to_jiffies(tout * 1000);
2081 		}
2082 		tout = schedule_timeout(tout);
2083 
2084 		snd_pcm_stream_lock_irq(substream);
2085 		group = snd_pcm_stream_group_ref(substream);
2086 		snd_pcm_group_for_each_entry(s, substream) {
2087 			if (s->runtime == to_check) {
2088 				remove_wait_queue(&to_check->sleep, &wait);
2089 				break;
2090 			}
2091 		}
2092 		snd_pcm_group_unref(group, substream);
2093 
2094 		if (card->shutdown) {
2095 			result = -ENODEV;
2096 			break;
2097 		}
2098 		if (tout == 0) {
2099 			if (substream->runtime->status->state == SNDRV_PCM_STATE_SUSPENDED)
2100 				result = -ESTRPIPE;
2101 			else {
2102 				dev_dbg(substream->pcm->card->dev,
2103 					"playback drain error (DMA or IRQ trouble?)\n");
2104 				snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2105 				result = -EIO;
2106 			}
2107 			break;
2108 		}
2109 	}
2110 
2111  unlock:
2112 	snd_pcm_stream_unlock_irq(substream);
2113 
2114 	return result;
2115 }
2116 
2117 /*
2118  * drop ioctl
2119  *
2120  * Immediately put all linked substreams into SETUP state.
2121  */
2122 static int snd_pcm_drop(struct snd_pcm_substream *substream)
2123 {
2124 	struct snd_pcm_runtime *runtime;
2125 	int result = 0;
2126 
2127 	if (PCM_RUNTIME_CHECK(substream))
2128 		return -ENXIO;
2129 	runtime = substream->runtime;
2130 
2131 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN ||
2132 	    runtime->status->state == SNDRV_PCM_STATE_DISCONNECTED)
2133 		return -EBADFD;
2134 
2135 	snd_pcm_stream_lock_irq(substream);
2136 	/* resume pause */
2137 	if (runtime->status->state == SNDRV_PCM_STATE_PAUSED)
2138 		snd_pcm_pause(substream, false);
2139 
2140 	snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2141 	/* runtime->control->appl_ptr = runtime->status->hw_ptr; */
2142 	snd_pcm_stream_unlock_irq(substream);
2143 
2144 	return result;
2145 }
2146 
2147 
2148 static bool is_pcm_file(struct file *file)
2149 {
2150 	struct inode *inode = file_inode(file);
2151 	struct snd_pcm *pcm;
2152 	unsigned int minor;
2153 
2154 	if (!S_ISCHR(inode->i_mode) || imajor(inode) != snd_major)
2155 		return false;
2156 	minor = iminor(inode);
2157 	pcm = snd_lookup_minor_data(minor, SNDRV_DEVICE_TYPE_PCM_PLAYBACK);
2158 	if (!pcm)
2159 		pcm = snd_lookup_minor_data(minor, SNDRV_DEVICE_TYPE_PCM_CAPTURE);
2160 	if (!pcm)
2161 		return false;
2162 	snd_card_unref(pcm->card);
2163 	return true;
2164 }
2165 
2166 /*
2167  * PCM link handling
2168  */
2169 static int snd_pcm_link(struct snd_pcm_substream *substream, int fd)
2170 {
2171 	int res = 0;
2172 	struct snd_pcm_file *pcm_file;
2173 	struct snd_pcm_substream *substream1;
2174 	struct snd_pcm_group *group, *target_group;
2175 	bool nonatomic = substream->pcm->nonatomic;
2176 	struct fd f = fdget(fd);
2177 
2178 	if (!f.file)
2179 		return -EBADFD;
2180 	if (!is_pcm_file(f.file)) {
2181 		res = -EBADFD;
2182 		goto _badf;
2183 	}
2184 	pcm_file = f.file->private_data;
2185 	substream1 = pcm_file->substream;
2186 
2187 	if (substream == substream1) {
2188 		res = -EINVAL;
2189 		goto _badf;
2190 	}
2191 
2192 	group = kzalloc(sizeof(*group), GFP_KERNEL);
2193 	if (!group) {
2194 		res = -ENOMEM;
2195 		goto _nolock;
2196 	}
2197 	snd_pcm_group_init(group);
2198 
2199 	down_write(&snd_pcm_link_rwsem);
2200 	if (substream->runtime->status->state == SNDRV_PCM_STATE_OPEN ||
2201 	    substream->runtime->status->state != substream1->runtime->status->state ||
2202 	    substream->pcm->nonatomic != substream1->pcm->nonatomic) {
2203 		res = -EBADFD;
2204 		goto _end;
2205 	}
2206 	if (snd_pcm_stream_linked(substream1)) {
2207 		res = -EALREADY;
2208 		goto _end;
2209 	}
2210 
2211 	snd_pcm_stream_lock_irq(substream);
2212 	if (!snd_pcm_stream_linked(substream)) {
2213 		snd_pcm_group_assign(substream, group);
2214 		group = NULL; /* assigned, don't free this one below */
2215 	}
2216 	target_group = substream->group;
2217 	snd_pcm_stream_unlock_irq(substream);
2218 
2219 	snd_pcm_group_lock_irq(target_group, nonatomic);
2220 	snd_pcm_stream_lock_nested(substream1);
2221 	snd_pcm_group_assign(substream1, target_group);
2222 	refcount_inc(&target_group->refs);
2223 	snd_pcm_stream_unlock(substream1);
2224 	snd_pcm_group_unlock_irq(target_group, nonatomic);
2225  _end:
2226 	up_write(&snd_pcm_link_rwsem);
2227  _nolock:
2228 	kfree(group);
2229  _badf:
2230 	fdput(f);
2231 	return res;
2232 }
2233 
2234 static void relink_to_local(struct snd_pcm_substream *substream)
2235 {
2236 	snd_pcm_stream_lock_nested(substream);
2237 	snd_pcm_group_assign(substream, &substream->self_group);
2238 	snd_pcm_stream_unlock(substream);
2239 }
2240 
2241 static int snd_pcm_unlink(struct snd_pcm_substream *substream)
2242 {
2243 	struct snd_pcm_group *group;
2244 	bool nonatomic = substream->pcm->nonatomic;
2245 	bool do_free = false;
2246 	int res = 0;
2247 
2248 	down_write(&snd_pcm_link_rwsem);
2249 
2250 	if (!snd_pcm_stream_linked(substream)) {
2251 		res = -EALREADY;
2252 		goto _end;
2253 	}
2254 
2255 	group = substream->group;
2256 	snd_pcm_group_lock_irq(group, nonatomic);
2257 
2258 	relink_to_local(substream);
2259 	refcount_dec(&group->refs);
2260 
2261 	/* detach the last stream, too */
2262 	if (list_is_singular(&group->substreams)) {
2263 		relink_to_local(list_first_entry(&group->substreams,
2264 						 struct snd_pcm_substream,
2265 						 link_list));
2266 		do_free = refcount_dec_and_test(&group->refs);
2267 	}
2268 
2269 	snd_pcm_group_unlock_irq(group, nonatomic);
2270 	if (do_free)
2271 		kfree(group);
2272 
2273        _end:
2274 	up_write(&snd_pcm_link_rwsem);
2275 	return res;
2276 }
2277 
2278 /*
2279  * hw configurator
2280  */
2281 static int snd_pcm_hw_rule_mul(struct snd_pcm_hw_params *params,
2282 			       struct snd_pcm_hw_rule *rule)
2283 {
2284 	struct snd_interval t;
2285 	snd_interval_mul(hw_param_interval_c(params, rule->deps[0]),
2286 		     hw_param_interval_c(params, rule->deps[1]), &t);
2287 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2288 }
2289 
2290 static int snd_pcm_hw_rule_div(struct snd_pcm_hw_params *params,
2291 			       struct snd_pcm_hw_rule *rule)
2292 {
2293 	struct snd_interval t;
2294 	snd_interval_div(hw_param_interval_c(params, rule->deps[0]),
2295 		     hw_param_interval_c(params, rule->deps[1]), &t);
2296 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2297 }
2298 
2299 static int snd_pcm_hw_rule_muldivk(struct snd_pcm_hw_params *params,
2300 				   struct snd_pcm_hw_rule *rule)
2301 {
2302 	struct snd_interval t;
2303 	snd_interval_muldivk(hw_param_interval_c(params, rule->deps[0]),
2304 			 hw_param_interval_c(params, rule->deps[1]),
2305 			 (unsigned long) rule->private, &t);
2306 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2307 }
2308 
2309 static int snd_pcm_hw_rule_mulkdiv(struct snd_pcm_hw_params *params,
2310 				   struct snd_pcm_hw_rule *rule)
2311 {
2312 	struct snd_interval t;
2313 	snd_interval_mulkdiv(hw_param_interval_c(params, rule->deps[0]),
2314 			 (unsigned long) rule->private,
2315 			 hw_param_interval_c(params, rule->deps[1]), &t);
2316 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2317 }
2318 
2319 static int snd_pcm_hw_rule_format(struct snd_pcm_hw_params *params,
2320 				  struct snd_pcm_hw_rule *rule)
2321 {
2322 	snd_pcm_format_t k;
2323 	const struct snd_interval *i =
2324 				hw_param_interval_c(params, rule->deps[0]);
2325 	struct snd_mask m;
2326 	struct snd_mask *mask = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
2327 	snd_mask_any(&m);
2328 	pcm_for_each_format(k) {
2329 		int bits;
2330 		if (!snd_mask_test_format(mask, k))
2331 			continue;
2332 		bits = snd_pcm_format_physical_width(k);
2333 		if (bits <= 0)
2334 			continue; /* ignore invalid formats */
2335 		if ((unsigned)bits < i->min || (unsigned)bits > i->max)
2336 			snd_mask_reset(&m, (__force unsigned)k);
2337 	}
2338 	return snd_mask_refine(mask, &m);
2339 }
2340 
2341 static int snd_pcm_hw_rule_sample_bits(struct snd_pcm_hw_params *params,
2342 				       struct snd_pcm_hw_rule *rule)
2343 {
2344 	struct snd_interval t;
2345 	snd_pcm_format_t k;
2346 
2347 	t.min = UINT_MAX;
2348 	t.max = 0;
2349 	t.openmin = 0;
2350 	t.openmax = 0;
2351 	pcm_for_each_format(k) {
2352 		int bits;
2353 		if (!snd_mask_test_format(hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT), k))
2354 			continue;
2355 		bits = snd_pcm_format_physical_width(k);
2356 		if (bits <= 0)
2357 			continue; /* ignore invalid formats */
2358 		if (t.min > (unsigned)bits)
2359 			t.min = bits;
2360 		if (t.max < (unsigned)bits)
2361 			t.max = bits;
2362 	}
2363 	t.integer = 1;
2364 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2365 }
2366 
2367 #if SNDRV_PCM_RATE_5512 != 1 << 0 || SNDRV_PCM_RATE_192000 != 1 << 12
2368 #error "Change this table"
2369 #endif
2370 
2371 static const unsigned int rates[] = {
2372 	5512, 8000, 11025, 16000, 22050, 32000, 44100,
2373 	48000, 64000, 88200, 96000, 176400, 192000, 352800, 384000
2374 };
2375 
2376 const struct snd_pcm_hw_constraint_list snd_pcm_known_rates = {
2377 	.count = ARRAY_SIZE(rates),
2378 	.list = rates,
2379 };
2380 
2381 static int snd_pcm_hw_rule_rate(struct snd_pcm_hw_params *params,
2382 				struct snd_pcm_hw_rule *rule)
2383 {
2384 	struct snd_pcm_hardware *hw = rule->private;
2385 	return snd_interval_list(hw_param_interval(params, rule->var),
2386 				 snd_pcm_known_rates.count,
2387 				 snd_pcm_known_rates.list, hw->rates);
2388 }
2389 
2390 static int snd_pcm_hw_rule_buffer_bytes_max(struct snd_pcm_hw_params *params,
2391 					    struct snd_pcm_hw_rule *rule)
2392 {
2393 	struct snd_interval t;
2394 	struct snd_pcm_substream *substream = rule->private;
2395 	t.min = 0;
2396 	t.max = substream->buffer_bytes_max;
2397 	t.openmin = 0;
2398 	t.openmax = 0;
2399 	t.integer = 1;
2400 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2401 }
2402 
2403 static int snd_pcm_hw_constraints_init(struct snd_pcm_substream *substream)
2404 {
2405 	struct snd_pcm_runtime *runtime = substream->runtime;
2406 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
2407 	int k, err;
2408 
2409 	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++) {
2410 		snd_mask_any(constrs_mask(constrs, k));
2411 	}
2412 
2413 	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++) {
2414 		snd_interval_any(constrs_interval(constrs, k));
2415 	}
2416 
2417 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_CHANNELS));
2418 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_BUFFER_SIZE));
2419 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_BUFFER_BYTES));
2420 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_SAMPLE_BITS));
2421 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_FRAME_BITS));
2422 
2423 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
2424 				   snd_pcm_hw_rule_format, NULL,
2425 				   SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
2426 	if (err < 0)
2427 		return err;
2428 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
2429 				  snd_pcm_hw_rule_sample_bits, NULL,
2430 				  SNDRV_PCM_HW_PARAM_FORMAT,
2431 				  SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
2432 	if (err < 0)
2433 		return err;
2434 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
2435 				  snd_pcm_hw_rule_div, NULL,
2436 				  SNDRV_PCM_HW_PARAM_FRAME_BITS, SNDRV_PCM_HW_PARAM_CHANNELS, -1);
2437 	if (err < 0)
2438 		return err;
2439 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS,
2440 				  snd_pcm_hw_rule_mul, NULL,
2441 				  SNDRV_PCM_HW_PARAM_SAMPLE_BITS, SNDRV_PCM_HW_PARAM_CHANNELS, -1);
2442 	if (err < 0)
2443 		return err;
2444 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS,
2445 				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
2446 				  SNDRV_PCM_HW_PARAM_PERIOD_BYTES, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
2447 	if (err < 0)
2448 		return err;
2449 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS,
2450 				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
2451 				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, -1);
2452 	if (err < 0)
2453 		return err;
2454 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
2455 				  snd_pcm_hw_rule_div, NULL,
2456 				  SNDRV_PCM_HW_PARAM_FRAME_BITS, SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
2457 	if (err < 0)
2458 		return err;
2459 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
2460 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2461 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_PERIOD_TIME, -1);
2462 	if (err < 0)
2463 		return err;
2464 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
2465 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2466 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_BUFFER_TIME, -1);
2467 	if (err < 0)
2468 		return err;
2469 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIODS,
2470 				  snd_pcm_hw_rule_div, NULL,
2471 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
2472 	if (err < 0)
2473 		return err;
2474 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
2475 				  snd_pcm_hw_rule_div, NULL,
2476 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_PERIODS, -1);
2477 	if (err < 0)
2478 		return err;
2479 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
2480 				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
2481 				  SNDRV_PCM_HW_PARAM_PERIOD_BYTES, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2482 	if (err < 0)
2483 		return err;
2484 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
2485 				  snd_pcm_hw_rule_muldivk, (void*) 1000000,
2486 				  SNDRV_PCM_HW_PARAM_PERIOD_TIME, SNDRV_PCM_HW_PARAM_RATE, -1);
2487 	if (err < 0)
2488 		return err;
2489 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
2490 				  snd_pcm_hw_rule_mul, NULL,
2491 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_PERIODS, -1);
2492 	if (err < 0)
2493 		return err;
2494 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
2495 				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
2496 				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2497 	if (err < 0)
2498 		return err;
2499 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
2500 				  snd_pcm_hw_rule_muldivk, (void*) 1000000,
2501 				  SNDRV_PCM_HW_PARAM_BUFFER_TIME, SNDRV_PCM_HW_PARAM_RATE, -1);
2502 	if (err < 0)
2503 		return err;
2504 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
2505 				  snd_pcm_hw_rule_muldivk, (void*) 8,
2506 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2507 	if (err < 0)
2508 		return err;
2509 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
2510 				  snd_pcm_hw_rule_muldivk, (void*) 8,
2511 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2512 	if (err < 0)
2513 		return err;
2514 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
2515 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2516 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_RATE, -1);
2517 	if (err < 0)
2518 		return err;
2519 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_TIME,
2520 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2521 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_RATE, -1);
2522 	if (err < 0)
2523 		return err;
2524 	return 0;
2525 }
2526 
2527 static int snd_pcm_hw_constraints_complete(struct snd_pcm_substream *substream)
2528 {
2529 	struct snd_pcm_runtime *runtime = substream->runtime;
2530 	struct snd_pcm_hardware *hw = &runtime->hw;
2531 	int err;
2532 	unsigned int mask = 0;
2533 
2534         if (hw->info & SNDRV_PCM_INFO_INTERLEAVED)
2535 		mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_RW_INTERLEAVED);
2536         if (hw->info & SNDRV_PCM_INFO_NONINTERLEAVED)
2537 		mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_RW_NONINTERLEAVED);
2538 	if (hw_support_mmap(substream)) {
2539 		if (hw->info & SNDRV_PCM_INFO_INTERLEAVED)
2540 			mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_MMAP_INTERLEAVED);
2541 		if (hw->info & SNDRV_PCM_INFO_NONINTERLEAVED)
2542 			mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED);
2543 		if (hw->info & SNDRV_PCM_INFO_COMPLEX)
2544 			mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_MMAP_COMPLEX);
2545 	}
2546 	err = snd_pcm_hw_constraint_mask(runtime, SNDRV_PCM_HW_PARAM_ACCESS, mask);
2547 	if (err < 0)
2548 		return err;
2549 
2550 	err = snd_pcm_hw_constraint_mask64(runtime, SNDRV_PCM_HW_PARAM_FORMAT, hw->formats);
2551 	if (err < 0)
2552 		return err;
2553 
2554 	err = snd_pcm_hw_constraint_mask(runtime, SNDRV_PCM_HW_PARAM_SUBFORMAT,
2555 					 PARAM_MASK_BIT(SNDRV_PCM_SUBFORMAT_STD));
2556 	if (err < 0)
2557 		return err;
2558 
2559 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_CHANNELS,
2560 					   hw->channels_min, hw->channels_max);
2561 	if (err < 0)
2562 		return err;
2563 
2564 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_RATE,
2565 					   hw->rate_min, hw->rate_max);
2566 	if (err < 0)
2567 		return err;
2568 
2569 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
2570 					   hw->period_bytes_min, hw->period_bytes_max);
2571 	if (err < 0)
2572 		return err;
2573 
2574 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIODS,
2575 					   hw->periods_min, hw->periods_max);
2576 	if (err < 0)
2577 		return err;
2578 
2579 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
2580 					   hw->period_bytes_min, hw->buffer_bytes_max);
2581 	if (err < 0)
2582 		return err;
2583 
2584 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
2585 				  snd_pcm_hw_rule_buffer_bytes_max, substream,
2586 				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, -1);
2587 	if (err < 0)
2588 		return err;
2589 
2590 	/* FIXME: remove */
2591 	if (runtime->dma_bytes) {
2592 		err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 0, runtime->dma_bytes);
2593 		if (err < 0)
2594 			return err;
2595 	}
2596 
2597 	if (!(hw->rates & (SNDRV_PCM_RATE_KNOT | SNDRV_PCM_RATE_CONTINUOUS))) {
2598 		err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
2599 					  snd_pcm_hw_rule_rate, hw,
2600 					  SNDRV_PCM_HW_PARAM_RATE, -1);
2601 		if (err < 0)
2602 			return err;
2603 	}
2604 
2605 	/* FIXME: this belong to lowlevel */
2606 	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
2607 
2608 	return 0;
2609 }
2610 
2611 static void pcm_release_private(struct snd_pcm_substream *substream)
2612 {
2613 	if (snd_pcm_stream_linked(substream))
2614 		snd_pcm_unlink(substream);
2615 }
2616 
2617 void snd_pcm_release_substream(struct snd_pcm_substream *substream)
2618 {
2619 	substream->ref_count--;
2620 	if (substream->ref_count > 0)
2621 		return;
2622 
2623 	snd_pcm_drop(substream);
2624 	if (substream->hw_opened) {
2625 		if (substream->runtime->status->state != SNDRV_PCM_STATE_OPEN)
2626 			do_hw_free(substream);
2627 		substream->ops->close(substream);
2628 		substream->hw_opened = 0;
2629 	}
2630 	if (cpu_latency_qos_request_active(&substream->latency_pm_qos_req))
2631 		cpu_latency_qos_remove_request(&substream->latency_pm_qos_req);
2632 	if (substream->pcm_release) {
2633 		substream->pcm_release(substream);
2634 		substream->pcm_release = NULL;
2635 	}
2636 	snd_pcm_detach_substream(substream);
2637 }
2638 EXPORT_SYMBOL(snd_pcm_release_substream);
2639 
2640 int snd_pcm_open_substream(struct snd_pcm *pcm, int stream,
2641 			   struct file *file,
2642 			   struct snd_pcm_substream **rsubstream)
2643 {
2644 	struct snd_pcm_substream *substream;
2645 	int err;
2646 
2647 	err = snd_pcm_attach_substream(pcm, stream, file, &substream);
2648 	if (err < 0)
2649 		return err;
2650 	if (substream->ref_count > 1) {
2651 		*rsubstream = substream;
2652 		return 0;
2653 	}
2654 
2655 	err = snd_pcm_hw_constraints_init(substream);
2656 	if (err < 0) {
2657 		pcm_dbg(pcm, "snd_pcm_hw_constraints_init failed\n");
2658 		goto error;
2659 	}
2660 
2661 	if ((err = substream->ops->open(substream)) < 0)
2662 		goto error;
2663 
2664 	substream->hw_opened = 1;
2665 
2666 	err = snd_pcm_hw_constraints_complete(substream);
2667 	if (err < 0) {
2668 		pcm_dbg(pcm, "snd_pcm_hw_constraints_complete failed\n");
2669 		goto error;
2670 	}
2671 
2672 	*rsubstream = substream;
2673 	return 0;
2674 
2675  error:
2676 	snd_pcm_release_substream(substream);
2677 	return err;
2678 }
2679 EXPORT_SYMBOL(snd_pcm_open_substream);
2680 
2681 static int snd_pcm_open_file(struct file *file,
2682 			     struct snd_pcm *pcm,
2683 			     int stream)
2684 {
2685 	struct snd_pcm_file *pcm_file;
2686 	struct snd_pcm_substream *substream;
2687 	int err;
2688 
2689 	err = snd_pcm_open_substream(pcm, stream, file, &substream);
2690 	if (err < 0)
2691 		return err;
2692 
2693 	pcm_file = kzalloc(sizeof(*pcm_file), GFP_KERNEL);
2694 	if (pcm_file == NULL) {
2695 		snd_pcm_release_substream(substream);
2696 		return -ENOMEM;
2697 	}
2698 	pcm_file->substream = substream;
2699 	if (substream->ref_count == 1)
2700 		substream->pcm_release = pcm_release_private;
2701 	file->private_data = pcm_file;
2702 
2703 	return 0;
2704 }
2705 
2706 static int snd_pcm_playback_open(struct inode *inode, struct file *file)
2707 {
2708 	struct snd_pcm *pcm;
2709 	int err = nonseekable_open(inode, file);
2710 	if (err < 0)
2711 		return err;
2712 	pcm = snd_lookup_minor_data(iminor(inode),
2713 				    SNDRV_DEVICE_TYPE_PCM_PLAYBACK);
2714 	err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_PLAYBACK);
2715 	if (pcm)
2716 		snd_card_unref(pcm->card);
2717 	return err;
2718 }
2719 
2720 static int snd_pcm_capture_open(struct inode *inode, struct file *file)
2721 {
2722 	struct snd_pcm *pcm;
2723 	int err = nonseekable_open(inode, file);
2724 	if (err < 0)
2725 		return err;
2726 	pcm = snd_lookup_minor_data(iminor(inode),
2727 				    SNDRV_DEVICE_TYPE_PCM_CAPTURE);
2728 	err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_CAPTURE);
2729 	if (pcm)
2730 		snd_card_unref(pcm->card);
2731 	return err;
2732 }
2733 
2734 static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream)
2735 {
2736 	int err;
2737 	wait_queue_entry_t wait;
2738 
2739 	if (pcm == NULL) {
2740 		err = -ENODEV;
2741 		goto __error1;
2742 	}
2743 	err = snd_card_file_add(pcm->card, file);
2744 	if (err < 0)
2745 		goto __error1;
2746 	if (!try_module_get(pcm->card->module)) {
2747 		err = -EFAULT;
2748 		goto __error2;
2749 	}
2750 	init_waitqueue_entry(&wait, current);
2751 	add_wait_queue(&pcm->open_wait, &wait);
2752 	mutex_lock(&pcm->open_mutex);
2753 	while (1) {
2754 		err = snd_pcm_open_file(file, pcm, stream);
2755 		if (err >= 0)
2756 			break;
2757 		if (err == -EAGAIN) {
2758 			if (file->f_flags & O_NONBLOCK) {
2759 				err = -EBUSY;
2760 				break;
2761 			}
2762 		} else
2763 			break;
2764 		set_current_state(TASK_INTERRUPTIBLE);
2765 		mutex_unlock(&pcm->open_mutex);
2766 		schedule();
2767 		mutex_lock(&pcm->open_mutex);
2768 		if (pcm->card->shutdown) {
2769 			err = -ENODEV;
2770 			break;
2771 		}
2772 		if (signal_pending(current)) {
2773 			err = -ERESTARTSYS;
2774 			break;
2775 		}
2776 	}
2777 	remove_wait_queue(&pcm->open_wait, &wait);
2778 	mutex_unlock(&pcm->open_mutex);
2779 	if (err < 0)
2780 		goto __error;
2781 	return err;
2782 
2783       __error:
2784 	module_put(pcm->card->module);
2785       __error2:
2786       	snd_card_file_remove(pcm->card, file);
2787       __error1:
2788       	return err;
2789 }
2790 
2791 static int snd_pcm_release(struct inode *inode, struct file *file)
2792 {
2793 	struct snd_pcm *pcm;
2794 	struct snd_pcm_substream *substream;
2795 	struct snd_pcm_file *pcm_file;
2796 
2797 	pcm_file = file->private_data;
2798 	substream = pcm_file->substream;
2799 	if (snd_BUG_ON(!substream))
2800 		return -ENXIO;
2801 	pcm = substream->pcm;
2802 	mutex_lock(&pcm->open_mutex);
2803 	snd_pcm_release_substream(substream);
2804 	kfree(pcm_file);
2805 	mutex_unlock(&pcm->open_mutex);
2806 	wake_up(&pcm->open_wait);
2807 	module_put(pcm->card->module);
2808 	snd_card_file_remove(pcm->card, file);
2809 	return 0;
2810 }
2811 
2812 /* check and update PCM state; return 0 or a negative error
2813  * call this inside PCM lock
2814  */
2815 static int do_pcm_hwsync(struct snd_pcm_substream *substream)
2816 {
2817 	switch (substream->runtime->status->state) {
2818 	case SNDRV_PCM_STATE_DRAINING:
2819 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
2820 			return -EBADFD;
2821 		fallthrough;
2822 	case SNDRV_PCM_STATE_RUNNING:
2823 		return snd_pcm_update_hw_ptr(substream);
2824 	case SNDRV_PCM_STATE_PREPARED:
2825 	case SNDRV_PCM_STATE_PAUSED:
2826 		return 0;
2827 	case SNDRV_PCM_STATE_SUSPENDED:
2828 		return -ESTRPIPE;
2829 	case SNDRV_PCM_STATE_XRUN:
2830 		return -EPIPE;
2831 	default:
2832 		return -EBADFD;
2833 	}
2834 }
2835 
2836 /* increase the appl_ptr; returns the processed frames or a negative error */
2837 static snd_pcm_sframes_t forward_appl_ptr(struct snd_pcm_substream *substream,
2838 					  snd_pcm_uframes_t frames,
2839 					   snd_pcm_sframes_t avail)
2840 {
2841 	struct snd_pcm_runtime *runtime = substream->runtime;
2842 	snd_pcm_sframes_t appl_ptr;
2843 	int ret;
2844 
2845 	if (avail <= 0)
2846 		return 0;
2847 	if (frames > (snd_pcm_uframes_t)avail)
2848 		frames = avail;
2849 	appl_ptr = runtime->control->appl_ptr + frames;
2850 	if (appl_ptr >= (snd_pcm_sframes_t)runtime->boundary)
2851 		appl_ptr -= runtime->boundary;
2852 	ret = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2853 	return ret < 0 ? ret : frames;
2854 }
2855 
2856 /* decrease the appl_ptr; returns the processed frames or zero for error */
2857 static snd_pcm_sframes_t rewind_appl_ptr(struct snd_pcm_substream *substream,
2858 					 snd_pcm_uframes_t frames,
2859 					 snd_pcm_sframes_t avail)
2860 {
2861 	struct snd_pcm_runtime *runtime = substream->runtime;
2862 	snd_pcm_sframes_t appl_ptr;
2863 	int ret;
2864 
2865 	if (avail <= 0)
2866 		return 0;
2867 	if (frames > (snd_pcm_uframes_t)avail)
2868 		frames = avail;
2869 	appl_ptr = runtime->control->appl_ptr - frames;
2870 	if (appl_ptr < 0)
2871 		appl_ptr += runtime->boundary;
2872 	ret = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2873 	/* NOTE: we return zero for errors because PulseAudio gets depressed
2874 	 * upon receiving an error from rewind ioctl and stops processing
2875 	 * any longer.  Returning zero means that no rewind is done, so
2876 	 * it's not absolutely wrong to answer like that.
2877 	 */
2878 	return ret < 0 ? 0 : frames;
2879 }
2880 
2881 static snd_pcm_sframes_t snd_pcm_rewind(struct snd_pcm_substream *substream,
2882 					snd_pcm_uframes_t frames)
2883 {
2884 	snd_pcm_sframes_t ret;
2885 
2886 	if (frames == 0)
2887 		return 0;
2888 
2889 	snd_pcm_stream_lock_irq(substream);
2890 	ret = do_pcm_hwsync(substream);
2891 	if (!ret)
2892 		ret = rewind_appl_ptr(substream, frames,
2893 				      snd_pcm_hw_avail(substream));
2894 	snd_pcm_stream_unlock_irq(substream);
2895 	return ret;
2896 }
2897 
2898 static snd_pcm_sframes_t snd_pcm_forward(struct snd_pcm_substream *substream,
2899 					 snd_pcm_uframes_t frames)
2900 {
2901 	snd_pcm_sframes_t ret;
2902 
2903 	if (frames == 0)
2904 		return 0;
2905 
2906 	snd_pcm_stream_lock_irq(substream);
2907 	ret = do_pcm_hwsync(substream);
2908 	if (!ret)
2909 		ret = forward_appl_ptr(substream, frames,
2910 				       snd_pcm_avail(substream));
2911 	snd_pcm_stream_unlock_irq(substream);
2912 	return ret;
2913 }
2914 
2915 static int snd_pcm_hwsync(struct snd_pcm_substream *substream)
2916 {
2917 	int err;
2918 
2919 	snd_pcm_stream_lock_irq(substream);
2920 	err = do_pcm_hwsync(substream);
2921 	snd_pcm_stream_unlock_irq(substream);
2922 	return err;
2923 }
2924 
2925 static int snd_pcm_delay(struct snd_pcm_substream *substream,
2926 			 snd_pcm_sframes_t *delay)
2927 {
2928 	int err;
2929 	snd_pcm_sframes_t n = 0;
2930 
2931 	snd_pcm_stream_lock_irq(substream);
2932 	err = do_pcm_hwsync(substream);
2933 	if (!err)
2934 		n = snd_pcm_calc_delay(substream);
2935 	snd_pcm_stream_unlock_irq(substream);
2936 	if (!err)
2937 		*delay = n;
2938 	return err;
2939 }
2940 
2941 static int snd_pcm_sync_ptr(struct snd_pcm_substream *substream,
2942 			    struct snd_pcm_sync_ptr __user *_sync_ptr)
2943 {
2944 	struct snd_pcm_runtime *runtime = substream->runtime;
2945 	struct snd_pcm_sync_ptr sync_ptr;
2946 	volatile struct snd_pcm_mmap_status *status;
2947 	volatile struct snd_pcm_mmap_control *control;
2948 	int err;
2949 
2950 	memset(&sync_ptr, 0, sizeof(sync_ptr));
2951 	if (get_user(sync_ptr.flags, (unsigned __user *)&(_sync_ptr->flags)))
2952 		return -EFAULT;
2953 	if (copy_from_user(&sync_ptr.c.control, &(_sync_ptr->c.control), sizeof(struct snd_pcm_mmap_control)))
2954 		return -EFAULT;
2955 	status = runtime->status;
2956 	control = runtime->control;
2957 	if (sync_ptr.flags & SNDRV_PCM_SYNC_PTR_HWSYNC) {
2958 		err = snd_pcm_hwsync(substream);
2959 		if (err < 0)
2960 			return err;
2961 	}
2962 	snd_pcm_stream_lock_irq(substream);
2963 	if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_APPL)) {
2964 		err = pcm_lib_apply_appl_ptr(substream,
2965 					     sync_ptr.c.control.appl_ptr);
2966 		if (err < 0) {
2967 			snd_pcm_stream_unlock_irq(substream);
2968 			return err;
2969 		}
2970 	} else {
2971 		sync_ptr.c.control.appl_ptr = control->appl_ptr;
2972 	}
2973 	if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_AVAIL_MIN))
2974 		control->avail_min = sync_ptr.c.control.avail_min;
2975 	else
2976 		sync_ptr.c.control.avail_min = control->avail_min;
2977 	sync_ptr.s.status.state = status->state;
2978 	sync_ptr.s.status.hw_ptr = status->hw_ptr;
2979 	sync_ptr.s.status.tstamp = status->tstamp;
2980 	sync_ptr.s.status.suspended_state = status->suspended_state;
2981 	sync_ptr.s.status.audio_tstamp = status->audio_tstamp;
2982 	snd_pcm_stream_unlock_irq(substream);
2983 	if (copy_to_user(_sync_ptr, &sync_ptr, sizeof(sync_ptr)))
2984 		return -EFAULT;
2985 	return 0;
2986 }
2987 
2988 struct snd_pcm_mmap_status32 {
2989 	snd_pcm_state_t state;
2990 	s32 pad1;
2991 	u32 hw_ptr;
2992 	s32 tstamp_sec;
2993 	s32 tstamp_nsec;
2994 	snd_pcm_state_t suspended_state;
2995 	s32 audio_tstamp_sec;
2996 	s32 audio_tstamp_nsec;
2997 } __attribute__((packed));
2998 
2999 struct snd_pcm_mmap_control32 {
3000 	u32 appl_ptr;
3001 	u32 avail_min;
3002 };
3003 
3004 struct snd_pcm_sync_ptr32 {
3005 	u32 flags;
3006 	union {
3007 		struct snd_pcm_mmap_status32 status;
3008 		unsigned char reserved[64];
3009 	} s;
3010 	union {
3011 		struct snd_pcm_mmap_control32 control;
3012 		unsigned char reserved[64];
3013 	} c;
3014 } __attribute__((packed));
3015 
3016 /* recalcuate the boundary within 32bit */
3017 static snd_pcm_uframes_t recalculate_boundary(struct snd_pcm_runtime *runtime)
3018 {
3019 	snd_pcm_uframes_t boundary;
3020 
3021 	if (! runtime->buffer_size)
3022 		return 0;
3023 	boundary = runtime->buffer_size;
3024 	while (boundary * 2 <= 0x7fffffffUL - runtime->buffer_size)
3025 		boundary *= 2;
3026 	return boundary;
3027 }
3028 
3029 static int snd_pcm_ioctl_sync_ptr_compat(struct snd_pcm_substream *substream,
3030 					 struct snd_pcm_sync_ptr32 __user *src)
3031 {
3032 	struct snd_pcm_runtime *runtime = substream->runtime;
3033 	volatile struct snd_pcm_mmap_status *status;
3034 	volatile struct snd_pcm_mmap_control *control;
3035 	u32 sflags;
3036 	struct snd_pcm_mmap_control scontrol;
3037 	struct snd_pcm_mmap_status sstatus;
3038 	snd_pcm_uframes_t boundary;
3039 	int err;
3040 
3041 	if (snd_BUG_ON(!runtime))
3042 		return -EINVAL;
3043 
3044 	if (get_user(sflags, &src->flags) ||
3045 	    get_user(scontrol.appl_ptr, &src->c.control.appl_ptr) ||
3046 	    get_user(scontrol.avail_min, &src->c.control.avail_min))
3047 		return -EFAULT;
3048 	if (sflags & SNDRV_PCM_SYNC_PTR_HWSYNC) {
3049 		err = snd_pcm_hwsync(substream);
3050 		if (err < 0)
3051 			return err;
3052 	}
3053 	status = runtime->status;
3054 	control = runtime->control;
3055 	boundary = recalculate_boundary(runtime);
3056 	if (! boundary)
3057 		boundary = 0x7fffffff;
3058 	snd_pcm_stream_lock_irq(substream);
3059 	/* FIXME: we should consider the boundary for the sync from app */
3060 	if (!(sflags & SNDRV_PCM_SYNC_PTR_APPL))
3061 		control->appl_ptr = scontrol.appl_ptr;
3062 	else
3063 		scontrol.appl_ptr = control->appl_ptr % boundary;
3064 	if (!(sflags & SNDRV_PCM_SYNC_PTR_AVAIL_MIN))
3065 		control->avail_min = scontrol.avail_min;
3066 	else
3067 		scontrol.avail_min = control->avail_min;
3068 	sstatus.state = status->state;
3069 	sstatus.hw_ptr = status->hw_ptr % boundary;
3070 	sstatus.tstamp = status->tstamp;
3071 	sstatus.suspended_state = status->suspended_state;
3072 	sstatus.audio_tstamp = status->audio_tstamp;
3073 	snd_pcm_stream_unlock_irq(substream);
3074 	if (put_user(sstatus.state, &src->s.status.state) ||
3075 	    put_user(sstatus.hw_ptr, &src->s.status.hw_ptr) ||
3076 	    put_user(sstatus.tstamp.tv_sec, &src->s.status.tstamp_sec) ||
3077 	    put_user(sstatus.tstamp.tv_nsec, &src->s.status.tstamp_nsec) ||
3078 	    put_user(sstatus.suspended_state, &src->s.status.suspended_state) ||
3079 	    put_user(sstatus.audio_tstamp.tv_sec, &src->s.status.audio_tstamp_sec) ||
3080 	    put_user(sstatus.audio_tstamp.tv_nsec, &src->s.status.audio_tstamp_nsec) ||
3081 	    put_user(scontrol.appl_ptr, &src->c.control.appl_ptr) ||
3082 	    put_user(scontrol.avail_min, &src->c.control.avail_min))
3083 		return -EFAULT;
3084 
3085 	return 0;
3086 }
3087 #define __SNDRV_PCM_IOCTL_SYNC_PTR32 _IOWR('A', 0x23, struct snd_pcm_sync_ptr32)
3088 
3089 static int snd_pcm_tstamp(struct snd_pcm_substream *substream, int __user *_arg)
3090 {
3091 	struct snd_pcm_runtime *runtime = substream->runtime;
3092 	int arg;
3093 
3094 	if (get_user(arg, _arg))
3095 		return -EFAULT;
3096 	if (arg < 0 || arg > SNDRV_PCM_TSTAMP_TYPE_LAST)
3097 		return -EINVAL;
3098 	runtime->tstamp_type = arg;
3099 	return 0;
3100 }
3101 
3102 static int snd_pcm_xferi_frames_ioctl(struct snd_pcm_substream *substream,
3103 				      struct snd_xferi __user *_xferi)
3104 {
3105 	struct snd_xferi xferi;
3106 	struct snd_pcm_runtime *runtime = substream->runtime;
3107 	snd_pcm_sframes_t result;
3108 
3109 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3110 		return -EBADFD;
3111 	if (put_user(0, &_xferi->result))
3112 		return -EFAULT;
3113 	if (copy_from_user(&xferi, _xferi, sizeof(xferi)))
3114 		return -EFAULT;
3115 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
3116 		result = snd_pcm_lib_write(substream, xferi.buf, xferi.frames);
3117 	else
3118 		result = snd_pcm_lib_read(substream, xferi.buf, xferi.frames);
3119 	if (put_user(result, &_xferi->result))
3120 		return -EFAULT;
3121 	return result < 0 ? result : 0;
3122 }
3123 
3124 static int snd_pcm_xfern_frames_ioctl(struct snd_pcm_substream *substream,
3125 				      struct snd_xfern __user *_xfern)
3126 {
3127 	struct snd_xfern xfern;
3128 	struct snd_pcm_runtime *runtime = substream->runtime;
3129 	void *bufs;
3130 	snd_pcm_sframes_t result;
3131 
3132 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3133 		return -EBADFD;
3134 	if (runtime->channels > 128)
3135 		return -EINVAL;
3136 	if (put_user(0, &_xfern->result))
3137 		return -EFAULT;
3138 	if (copy_from_user(&xfern, _xfern, sizeof(xfern)))
3139 		return -EFAULT;
3140 
3141 	bufs = memdup_user(xfern.bufs, sizeof(void *) * runtime->channels);
3142 	if (IS_ERR(bufs))
3143 		return PTR_ERR(bufs);
3144 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
3145 		result = snd_pcm_lib_writev(substream, bufs, xfern.frames);
3146 	else
3147 		result = snd_pcm_lib_readv(substream, bufs, xfern.frames);
3148 	kfree(bufs);
3149 	if (put_user(result, &_xfern->result))
3150 		return -EFAULT;
3151 	return result < 0 ? result : 0;
3152 }
3153 
3154 static int snd_pcm_rewind_ioctl(struct snd_pcm_substream *substream,
3155 				snd_pcm_uframes_t __user *_frames)
3156 {
3157 	snd_pcm_uframes_t frames;
3158 	snd_pcm_sframes_t result;
3159 
3160 	if (get_user(frames, _frames))
3161 		return -EFAULT;
3162 	if (put_user(0, _frames))
3163 		return -EFAULT;
3164 	result = snd_pcm_rewind(substream, frames);
3165 	if (put_user(result, _frames))
3166 		return -EFAULT;
3167 	return result < 0 ? result : 0;
3168 }
3169 
3170 static int snd_pcm_forward_ioctl(struct snd_pcm_substream *substream,
3171 				 snd_pcm_uframes_t __user *_frames)
3172 {
3173 	snd_pcm_uframes_t frames;
3174 	snd_pcm_sframes_t result;
3175 
3176 	if (get_user(frames, _frames))
3177 		return -EFAULT;
3178 	if (put_user(0, _frames))
3179 		return -EFAULT;
3180 	result = snd_pcm_forward(substream, frames);
3181 	if (put_user(result, _frames))
3182 		return -EFAULT;
3183 	return result < 0 ? result : 0;
3184 }
3185 
3186 static int snd_pcm_common_ioctl(struct file *file,
3187 				 struct snd_pcm_substream *substream,
3188 				 unsigned int cmd, void __user *arg)
3189 {
3190 	struct snd_pcm_file *pcm_file = file->private_data;
3191 	int res;
3192 
3193 	if (PCM_RUNTIME_CHECK(substream))
3194 		return -ENXIO;
3195 
3196 	res = snd_power_wait(substream->pcm->card, SNDRV_CTL_POWER_D0);
3197 	if (res < 0)
3198 		return res;
3199 
3200 	switch (cmd) {
3201 	case SNDRV_PCM_IOCTL_PVERSION:
3202 		return put_user(SNDRV_PCM_VERSION, (int __user *)arg) ? -EFAULT : 0;
3203 	case SNDRV_PCM_IOCTL_INFO:
3204 		return snd_pcm_info_user(substream, arg);
3205 	case SNDRV_PCM_IOCTL_TSTAMP:	/* just for compatibility */
3206 		return 0;
3207 	case SNDRV_PCM_IOCTL_TTSTAMP:
3208 		return snd_pcm_tstamp(substream, arg);
3209 	case SNDRV_PCM_IOCTL_USER_PVERSION:
3210 		if (get_user(pcm_file->user_pversion,
3211 			     (unsigned int __user *)arg))
3212 			return -EFAULT;
3213 		return 0;
3214 	case SNDRV_PCM_IOCTL_HW_REFINE:
3215 		return snd_pcm_hw_refine_user(substream, arg);
3216 	case SNDRV_PCM_IOCTL_HW_PARAMS:
3217 		return snd_pcm_hw_params_user(substream, arg);
3218 	case SNDRV_PCM_IOCTL_HW_FREE:
3219 		return snd_pcm_hw_free(substream);
3220 	case SNDRV_PCM_IOCTL_SW_PARAMS:
3221 		return snd_pcm_sw_params_user(substream, arg);
3222 	case SNDRV_PCM_IOCTL_STATUS32:
3223 		return snd_pcm_status_user32(substream, arg, false);
3224 	case SNDRV_PCM_IOCTL_STATUS_EXT32:
3225 		return snd_pcm_status_user32(substream, arg, true);
3226 	case SNDRV_PCM_IOCTL_STATUS64:
3227 		return snd_pcm_status_user64(substream, arg, false);
3228 	case SNDRV_PCM_IOCTL_STATUS_EXT64:
3229 		return snd_pcm_status_user64(substream, arg, true);
3230 	case SNDRV_PCM_IOCTL_CHANNEL_INFO:
3231 		return snd_pcm_channel_info_user(substream, arg);
3232 	case SNDRV_PCM_IOCTL_PREPARE:
3233 		return snd_pcm_prepare(substream, file);
3234 	case SNDRV_PCM_IOCTL_RESET:
3235 		return snd_pcm_reset(substream);
3236 	case SNDRV_PCM_IOCTL_START:
3237 		return snd_pcm_start_lock_irq(substream);
3238 	case SNDRV_PCM_IOCTL_LINK:
3239 		return snd_pcm_link(substream, (int)(unsigned long) arg);
3240 	case SNDRV_PCM_IOCTL_UNLINK:
3241 		return snd_pcm_unlink(substream);
3242 	case SNDRV_PCM_IOCTL_RESUME:
3243 		return snd_pcm_resume(substream);
3244 	case SNDRV_PCM_IOCTL_XRUN:
3245 		return snd_pcm_xrun(substream);
3246 	case SNDRV_PCM_IOCTL_HWSYNC:
3247 		return snd_pcm_hwsync(substream);
3248 	case SNDRV_PCM_IOCTL_DELAY:
3249 	{
3250 		snd_pcm_sframes_t delay;
3251 		snd_pcm_sframes_t __user *res = arg;
3252 		int err;
3253 
3254 		err = snd_pcm_delay(substream, &delay);
3255 		if (err)
3256 			return err;
3257 		if (put_user(delay, res))
3258 			return -EFAULT;
3259 		return 0;
3260 	}
3261 	case __SNDRV_PCM_IOCTL_SYNC_PTR32:
3262 		return snd_pcm_ioctl_sync_ptr_compat(substream, arg);
3263 	case __SNDRV_PCM_IOCTL_SYNC_PTR64:
3264 		return snd_pcm_sync_ptr(substream, arg);
3265 #ifdef CONFIG_SND_SUPPORT_OLD_API
3266 	case SNDRV_PCM_IOCTL_HW_REFINE_OLD:
3267 		return snd_pcm_hw_refine_old_user(substream, arg);
3268 	case SNDRV_PCM_IOCTL_HW_PARAMS_OLD:
3269 		return snd_pcm_hw_params_old_user(substream, arg);
3270 #endif
3271 	case SNDRV_PCM_IOCTL_DRAIN:
3272 		return snd_pcm_drain(substream, file);
3273 	case SNDRV_PCM_IOCTL_DROP:
3274 		return snd_pcm_drop(substream);
3275 	case SNDRV_PCM_IOCTL_PAUSE:
3276 		return snd_pcm_pause_lock_irq(substream, (unsigned long)arg);
3277 	case SNDRV_PCM_IOCTL_WRITEI_FRAMES:
3278 	case SNDRV_PCM_IOCTL_READI_FRAMES:
3279 		return snd_pcm_xferi_frames_ioctl(substream, arg);
3280 	case SNDRV_PCM_IOCTL_WRITEN_FRAMES:
3281 	case SNDRV_PCM_IOCTL_READN_FRAMES:
3282 		return snd_pcm_xfern_frames_ioctl(substream, arg);
3283 	case SNDRV_PCM_IOCTL_REWIND:
3284 		return snd_pcm_rewind_ioctl(substream, arg);
3285 	case SNDRV_PCM_IOCTL_FORWARD:
3286 		return snd_pcm_forward_ioctl(substream, arg);
3287 	}
3288 	pcm_dbg(substream->pcm, "unknown ioctl = 0x%x\n", cmd);
3289 	return -ENOTTY;
3290 }
3291 
3292 static long snd_pcm_ioctl(struct file *file, unsigned int cmd,
3293 			  unsigned long arg)
3294 {
3295 	struct snd_pcm_file *pcm_file;
3296 
3297 	pcm_file = file->private_data;
3298 
3299 	if (((cmd >> 8) & 0xff) != 'A')
3300 		return -ENOTTY;
3301 
3302 	return snd_pcm_common_ioctl(file, pcm_file->substream, cmd,
3303 				     (void __user *)arg);
3304 }
3305 
3306 /**
3307  * snd_pcm_kernel_ioctl - Execute PCM ioctl in the kernel-space
3308  * @substream: PCM substream
3309  * @cmd: IOCTL cmd
3310  * @arg: IOCTL argument
3311  *
3312  * The function is provided primarily for OSS layer and USB gadget drivers,
3313  * and it allows only the limited set of ioctls (hw_params, sw_params,
3314  * prepare, start, drain, drop, forward).
3315  */
3316 int snd_pcm_kernel_ioctl(struct snd_pcm_substream *substream,
3317 			 unsigned int cmd, void *arg)
3318 {
3319 	snd_pcm_uframes_t *frames = arg;
3320 	snd_pcm_sframes_t result;
3321 
3322 	switch (cmd) {
3323 	case SNDRV_PCM_IOCTL_FORWARD:
3324 	{
3325 		/* provided only for OSS; capture-only and no value returned */
3326 		if (substream->stream != SNDRV_PCM_STREAM_CAPTURE)
3327 			return -EINVAL;
3328 		result = snd_pcm_forward(substream, *frames);
3329 		return result < 0 ? result : 0;
3330 	}
3331 	case SNDRV_PCM_IOCTL_HW_PARAMS:
3332 		return snd_pcm_hw_params(substream, arg);
3333 	case SNDRV_PCM_IOCTL_SW_PARAMS:
3334 		return snd_pcm_sw_params(substream, arg);
3335 	case SNDRV_PCM_IOCTL_PREPARE:
3336 		return snd_pcm_prepare(substream, NULL);
3337 	case SNDRV_PCM_IOCTL_START:
3338 		return snd_pcm_start_lock_irq(substream);
3339 	case SNDRV_PCM_IOCTL_DRAIN:
3340 		return snd_pcm_drain(substream, NULL);
3341 	case SNDRV_PCM_IOCTL_DROP:
3342 		return snd_pcm_drop(substream);
3343 	case SNDRV_PCM_IOCTL_DELAY:
3344 		return snd_pcm_delay(substream, frames);
3345 	default:
3346 		return -EINVAL;
3347 	}
3348 }
3349 EXPORT_SYMBOL(snd_pcm_kernel_ioctl);
3350 
3351 static ssize_t snd_pcm_read(struct file *file, char __user *buf, size_t count,
3352 			    loff_t * offset)
3353 {
3354 	struct snd_pcm_file *pcm_file;
3355 	struct snd_pcm_substream *substream;
3356 	struct snd_pcm_runtime *runtime;
3357 	snd_pcm_sframes_t result;
3358 
3359 	pcm_file = file->private_data;
3360 	substream = pcm_file->substream;
3361 	if (PCM_RUNTIME_CHECK(substream))
3362 		return -ENXIO;
3363 	runtime = substream->runtime;
3364 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3365 		return -EBADFD;
3366 	if (!frame_aligned(runtime, count))
3367 		return -EINVAL;
3368 	count = bytes_to_frames(runtime, count);
3369 	result = snd_pcm_lib_read(substream, buf, count);
3370 	if (result > 0)
3371 		result = frames_to_bytes(runtime, result);
3372 	return result;
3373 }
3374 
3375 static ssize_t snd_pcm_write(struct file *file, const char __user *buf,
3376 			     size_t count, loff_t * offset)
3377 {
3378 	struct snd_pcm_file *pcm_file;
3379 	struct snd_pcm_substream *substream;
3380 	struct snd_pcm_runtime *runtime;
3381 	snd_pcm_sframes_t result;
3382 
3383 	pcm_file = file->private_data;
3384 	substream = pcm_file->substream;
3385 	if (PCM_RUNTIME_CHECK(substream))
3386 		return -ENXIO;
3387 	runtime = substream->runtime;
3388 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3389 		return -EBADFD;
3390 	if (!frame_aligned(runtime, count))
3391 		return -EINVAL;
3392 	count = bytes_to_frames(runtime, count);
3393 	result = snd_pcm_lib_write(substream, buf, count);
3394 	if (result > 0)
3395 		result = frames_to_bytes(runtime, result);
3396 	return result;
3397 }
3398 
3399 static ssize_t snd_pcm_readv(struct kiocb *iocb, struct iov_iter *to)
3400 {
3401 	struct snd_pcm_file *pcm_file;
3402 	struct snd_pcm_substream *substream;
3403 	struct snd_pcm_runtime *runtime;
3404 	snd_pcm_sframes_t result;
3405 	unsigned long i;
3406 	void __user **bufs;
3407 	snd_pcm_uframes_t frames;
3408 
3409 	pcm_file = iocb->ki_filp->private_data;
3410 	substream = pcm_file->substream;
3411 	if (PCM_RUNTIME_CHECK(substream))
3412 		return -ENXIO;
3413 	runtime = substream->runtime;
3414 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3415 		return -EBADFD;
3416 	if (!iter_is_iovec(to))
3417 		return -EINVAL;
3418 	if (to->nr_segs > 1024 || to->nr_segs != runtime->channels)
3419 		return -EINVAL;
3420 	if (!frame_aligned(runtime, to->iov->iov_len))
3421 		return -EINVAL;
3422 	frames = bytes_to_samples(runtime, to->iov->iov_len);
3423 	bufs = kmalloc_array(to->nr_segs, sizeof(void *), GFP_KERNEL);
3424 	if (bufs == NULL)
3425 		return -ENOMEM;
3426 	for (i = 0; i < to->nr_segs; ++i)
3427 		bufs[i] = to->iov[i].iov_base;
3428 	result = snd_pcm_lib_readv(substream, bufs, frames);
3429 	if (result > 0)
3430 		result = frames_to_bytes(runtime, result);
3431 	kfree(bufs);
3432 	return result;
3433 }
3434 
3435 static ssize_t snd_pcm_writev(struct kiocb *iocb, struct iov_iter *from)
3436 {
3437 	struct snd_pcm_file *pcm_file;
3438 	struct snd_pcm_substream *substream;
3439 	struct snd_pcm_runtime *runtime;
3440 	snd_pcm_sframes_t result;
3441 	unsigned long i;
3442 	void __user **bufs;
3443 	snd_pcm_uframes_t frames;
3444 
3445 	pcm_file = iocb->ki_filp->private_data;
3446 	substream = pcm_file->substream;
3447 	if (PCM_RUNTIME_CHECK(substream))
3448 		return -ENXIO;
3449 	runtime = substream->runtime;
3450 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3451 		return -EBADFD;
3452 	if (!iter_is_iovec(from))
3453 		return -EINVAL;
3454 	if (from->nr_segs > 128 || from->nr_segs != runtime->channels ||
3455 	    !frame_aligned(runtime, from->iov->iov_len))
3456 		return -EINVAL;
3457 	frames = bytes_to_samples(runtime, from->iov->iov_len);
3458 	bufs = kmalloc_array(from->nr_segs, sizeof(void *), GFP_KERNEL);
3459 	if (bufs == NULL)
3460 		return -ENOMEM;
3461 	for (i = 0; i < from->nr_segs; ++i)
3462 		bufs[i] = from->iov[i].iov_base;
3463 	result = snd_pcm_lib_writev(substream, bufs, frames);
3464 	if (result > 0)
3465 		result = frames_to_bytes(runtime, result);
3466 	kfree(bufs);
3467 	return result;
3468 }
3469 
3470 static __poll_t snd_pcm_poll(struct file *file, poll_table *wait)
3471 {
3472 	struct snd_pcm_file *pcm_file;
3473 	struct snd_pcm_substream *substream;
3474 	struct snd_pcm_runtime *runtime;
3475 	__poll_t mask, ok;
3476 	snd_pcm_uframes_t avail;
3477 
3478 	pcm_file = file->private_data;
3479 
3480 	substream = pcm_file->substream;
3481 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
3482 		ok = EPOLLOUT | EPOLLWRNORM;
3483 	else
3484 		ok = EPOLLIN | EPOLLRDNORM;
3485 	if (PCM_RUNTIME_CHECK(substream))
3486 		return ok | EPOLLERR;
3487 
3488 	runtime = substream->runtime;
3489 	poll_wait(file, &runtime->sleep, wait);
3490 
3491 	mask = 0;
3492 	snd_pcm_stream_lock_irq(substream);
3493 	avail = snd_pcm_avail(substream);
3494 	switch (runtime->status->state) {
3495 	case SNDRV_PCM_STATE_RUNNING:
3496 	case SNDRV_PCM_STATE_PREPARED:
3497 	case SNDRV_PCM_STATE_PAUSED:
3498 		if (avail >= runtime->control->avail_min)
3499 			mask = ok;
3500 		break;
3501 	case SNDRV_PCM_STATE_DRAINING:
3502 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
3503 			mask = ok;
3504 			if (!avail)
3505 				mask |= EPOLLERR;
3506 		}
3507 		break;
3508 	default:
3509 		mask = ok | EPOLLERR;
3510 		break;
3511 	}
3512 	snd_pcm_stream_unlock_irq(substream);
3513 	return mask;
3514 }
3515 
3516 /*
3517  * mmap support
3518  */
3519 
3520 /*
3521  * Only on coherent architectures, we can mmap the status and the control records
3522  * for effcient data transfer.  On others, we have to use HWSYNC ioctl...
3523  */
3524 #if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_ALPHA)
3525 /*
3526  * mmap status record
3527  */
3528 static vm_fault_t snd_pcm_mmap_status_fault(struct vm_fault *vmf)
3529 {
3530 	struct snd_pcm_substream *substream = vmf->vma->vm_private_data;
3531 	struct snd_pcm_runtime *runtime;
3532 
3533 	if (substream == NULL)
3534 		return VM_FAULT_SIGBUS;
3535 	runtime = substream->runtime;
3536 	vmf->page = virt_to_page(runtime->status);
3537 	get_page(vmf->page);
3538 	return 0;
3539 }
3540 
3541 static const struct vm_operations_struct snd_pcm_vm_ops_status =
3542 {
3543 	.fault =	snd_pcm_mmap_status_fault,
3544 };
3545 
3546 static int snd_pcm_mmap_status(struct snd_pcm_substream *substream, struct file *file,
3547 			       struct vm_area_struct *area)
3548 {
3549 	long size;
3550 	if (!(area->vm_flags & VM_READ))
3551 		return -EINVAL;
3552 	size = area->vm_end - area->vm_start;
3553 	if (size != PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)))
3554 		return -EINVAL;
3555 	area->vm_ops = &snd_pcm_vm_ops_status;
3556 	area->vm_private_data = substream;
3557 	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
3558 	return 0;
3559 }
3560 
3561 /*
3562  * mmap control record
3563  */
3564 static vm_fault_t snd_pcm_mmap_control_fault(struct vm_fault *vmf)
3565 {
3566 	struct snd_pcm_substream *substream = vmf->vma->vm_private_data;
3567 	struct snd_pcm_runtime *runtime;
3568 
3569 	if (substream == NULL)
3570 		return VM_FAULT_SIGBUS;
3571 	runtime = substream->runtime;
3572 	vmf->page = virt_to_page(runtime->control);
3573 	get_page(vmf->page);
3574 	return 0;
3575 }
3576 
3577 static const struct vm_operations_struct snd_pcm_vm_ops_control =
3578 {
3579 	.fault =	snd_pcm_mmap_control_fault,
3580 };
3581 
3582 static int snd_pcm_mmap_control(struct snd_pcm_substream *substream, struct file *file,
3583 				struct vm_area_struct *area)
3584 {
3585 	long size;
3586 	if (!(area->vm_flags & VM_READ))
3587 		return -EINVAL;
3588 	size = area->vm_end - area->vm_start;
3589 	if (size != PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)))
3590 		return -EINVAL;
3591 	area->vm_ops = &snd_pcm_vm_ops_control;
3592 	area->vm_private_data = substream;
3593 	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
3594 	return 0;
3595 }
3596 
3597 static bool pcm_status_mmap_allowed(struct snd_pcm_file *pcm_file)
3598 {
3599 	/* See pcm_control_mmap_allowed() below.
3600 	 * Since older alsa-lib requires both status and control mmaps to be
3601 	 * coupled, we have to disable the status mmap for old alsa-lib, too.
3602 	 */
3603 	if (pcm_file->user_pversion < SNDRV_PROTOCOL_VERSION(2, 0, 14) &&
3604 	    (pcm_file->substream->runtime->hw.info & SNDRV_PCM_INFO_SYNC_APPLPTR))
3605 		return false;
3606 	return true;
3607 }
3608 
3609 static bool pcm_control_mmap_allowed(struct snd_pcm_file *pcm_file)
3610 {
3611 	if (pcm_file->no_compat_mmap)
3612 		return false;
3613 	/* Disallow the control mmap when SYNC_APPLPTR flag is set;
3614 	 * it enforces the user-space to fall back to snd_pcm_sync_ptr(),
3615 	 * thus it effectively assures the manual update of appl_ptr.
3616 	 */
3617 	if (pcm_file->substream->runtime->hw.info & SNDRV_PCM_INFO_SYNC_APPLPTR)
3618 		return false;
3619 	return true;
3620 }
3621 
3622 #else /* ! coherent mmap */
3623 /*
3624  * don't support mmap for status and control records.
3625  */
3626 #define pcm_status_mmap_allowed(pcm_file)	false
3627 #define pcm_control_mmap_allowed(pcm_file)	false
3628 
3629 static int snd_pcm_mmap_status(struct snd_pcm_substream *substream, struct file *file,
3630 			       struct vm_area_struct *area)
3631 {
3632 	return -ENXIO;
3633 }
3634 static int snd_pcm_mmap_control(struct snd_pcm_substream *substream, struct file *file,
3635 				struct vm_area_struct *area)
3636 {
3637 	return -ENXIO;
3638 }
3639 #endif /* coherent mmap */
3640 
3641 static inline struct page *
3642 snd_pcm_default_page_ops(struct snd_pcm_substream *substream, unsigned long ofs)
3643 {
3644 	void *vaddr = substream->runtime->dma_area + ofs;
3645 
3646 	switch (substream->dma_buffer.dev.type) {
3647 #ifdef CONFIG_SND_DMA_SGBUF
3648 	case SNDRV_DMA_TYPE_DEV_SG:
3649 	case SNDRV_DMA_TYPE_DEV_UC_SG:
3650 		return snd_pcm_sgbuf_ops_page(substream, ofs);
3651 #endif /* CONFIG_SND_DMA_SGBUF */
3652 	case SNDRV_DMA_TYPE_VMALLOC:
3653 		return vmalloc_to_page(vaddr);
3654 	default:
3655 		return virt_to_page(vaddr);
3656 	}
3657 }
3658 
3659 /*
3660  * fault callback for mmapping a RAM page
3661  */
3662 static vm_fault_t snd_pcm_mmap_data_fault(struct vm_fault *vmf)
3663 {
3664 	struct snd_pcm_substream *substream = vmf->vma->vm_private_data;
3665 	struct snd_pcm_runtime *runtime;
3666 	unsigned long offset;
3667 	struct page * page;
3668 	size_t dma_bytes;
3669 
3670 	if (substream == NULL)
3671 		return VM_FAULT_SIGBUS;
3672 	runtime = substream->runtime;
3673 	offset = vmf->pgoff << PAGE_SHIFT;
3674 	dma_bytes = PAGE_ALIGN(runtime->dma_bytes);
3675 	if (offset > dma_bytes - PAGE_SIZE)
3676 		return VM_FAULT_SIGBUS;
3677 	if (substream->ops->page)
3678 		page = substream->ops->page(substream, offset);
3679 	else
3680 		page = snd_pcm_default_page_ops(substream, offset);
3681 	if (!page)
3682 		return VM_FAULT_SIGBUS;
3683 	get_page(page);
3684 	vmf->page = page;
3685 	return 0;
3686 }
3687 
3688 static const struct vm_operations_struct snd_pcm_vm_ops_data = {
3689 	.open =		snd_pcm_mmap_data_open,
3690 	.close =	snd_pcm_mmap_data_close,
3691 };
3692 
3693 static const struct vm_operations_struct snd_pcm_vm_ops_data_fault = {
3694 	.open =		snd_pcm_mmap_data_open,
3695 	.close =	snd_pcm_mmap_data_close,
3696 	.fault =	snd_pcm_mmap_data_fault,
3697 };
3698 
3699 /*
3700  * mmap the DMA buffer on RAM
3701  */
3702 
3703 /**
3704  * snd_pcm_lib_default_mmap - Default PCM data mmap function
3705  * @substream: PCM substream
3706  * @area: VMA
3707  *
3708  * This is the default mmap handler for PCM data.  When mmap pcm_ops is NULL,
3709  * this function is invoked implicitly.
3710  */
3711 int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
3712 			     struct vm_area_struct *area)
3713 {
3714 	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
3715 #ifdef CONFIG_GENERIC_ALLOCATOR
3716 	if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV_IRAM) {
3717 		area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
3718 		return remap_pfn_range(area, area->vm_start,
3719 				substream->dma_buffer.addr >> PAGE_SHIFT,
3720 				area->vm_end - area->vm_start, area->vm_page_prot);
3721 	}
3722 #endif /* CONFIG_GENERIC_ALLOCATOR */
3723 	if (IS_ENABLED(CONFIG_HAS_DMA) && !substream->ops->page &&
3724 	    (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV ||
3725 	     substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV_UC))
3726 		return dma_mmap_coherent(substream->dma_buffer.dev.dev,
3727 					 area,
3728 					 substream->runtime->dma_area,
3729 					 substream->runtime->dma_addr,
3730 					 substream->runtime->dma_bytes);
3731 	/* mmap with fault handler */
3732 	area->vm_ops = &snd_pcm_vm_ops_data_fault;
3733 	return 0;
3734 }
3735 EXPORT_SYMBOL_GPL(snd_pcm_lib_default_mmap);
3736 
3737 /*
3738  * mmap the DMA buffer on I/O memory area
3739  */
3740 #if SNDRV_PCM_INFO_MMAP_IOMEM
3741 /**
3742  * snd_pcm_lib_mmap_iomem - Default PCM data mmap function for I/O mem
3743  * @substream: PCM substream
3744  * @area: VMA
3745  *
3746  * When your hardware uses the iomapped pages as the hardware buffer and
3747  * wants to mmap it, pass this function as mmap pcm_ops.  Note that this
3748  * is supposed to work only on limited architectures.
3749  */
3750 int snd_pcm_lib_mmap_iomem(struct snd_pcm_substream *substream,
3751 			   struct vm_area_struct *area)
3752 {
3753 	struct snd_pcm_runtime *runtime = substream->runtime;
3754 
3755 	area->vm_page_prot = pgprot_noncached(area->vm_page_prot);
3756 	return vm_iomap_memory(area, runtime->dma_addr, runtime->dma_bytes);
3757 }
3758 EXPORT_SYMBOL(snd_pcm_lib_mmap_iomem);
3759 #endif /* SNDRV_PCM_INFO_MMAP */
3760 
3761 /*
3762  * mmap DMA buffer
3763  */
3764 int snd_pcm_mmap_data(struct snd_pcm_substream *substream, struct file *file,
3765 		      struct vm_area_struct *area)
3766 {
3767 	struct snd_pcm_runtime *runtime;
3768 	long size;
3769 	unsigned long offset;
3770 	size_t dma_bytes;
3771 	int err;
3772 
3773 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
3774 		if (!(area->vm_flags & (VM_WRITE|VM_READ)))
3775 			return -EINVAL;
3776 	} else {
3777 		if (!(area->vm_flags & VM_READ))
3778 			return -EINVAL;
3779 	}
3780 	runtime = substream->runtime;
3781 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3782 		return -EBADFD;
3783 	if (!(runtime->info & SNDRV_PCM_INFO_MMAP))
3784 		return -ENXIO;
3785 	if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
3786 	    runtime->access == SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
3787 		return -EINVAL;
3788 	size = area->vm_end - area->vm_start;
3789 	offset = area->vm_pgoff << PAGE_SHIFT;
3790 	dma_bytes = PAGE_ALIGN(runtime->dma_bytes);
3791 	if ((size_t)size > dma_bytes)
3792 		return -EINVAL;
3793 	if (offset > dma_bytes - size)
3794 		return -EINVAL;
3795 
3796 	area->vm_ops = &snd_pcm_vm_ops_data;
3797 	area->vm_private_data = substream;
3798 	if (substream->ops->mmap)
3799 		err = substream->ops->mmap(substream, area);
3800 	else
3801 		err = snd_pcm_lib_default_mmap(substream, area);
3802 	if (!err)
3803 		atomic_inc(&substream->mmap_count);
3804 	return err;
3805 }
3806 EXPORT_SYMBOL(snd_pcm_mmap_data);
3807 
3808 static int snd_pcm_mmap(struct file *file, struct vm_area_struct *area)
3809 {
3810 	struct snd_pcm_file * pcm_file;
3811 	struct snd_pcm_substream *substream;
3812 	unsigned long offset;
3813 
3814 	pcm_file = file->private_data;
3815 	substream = pcm_file->substream;
3816 	if (PCM_RUNTIME_CHECK(substream))
3817 		return -ENXIO;
3818 
3819 	offset = area->vm_pgoff << PAGE_SHIFT;
3820 	switch (offset) {
3821 	case SNDRV_PCM_MMAP_OFFSET_STATUS_OLD:
3822 		if (pcm_file->no_compat_mmap || !IS_ENABLED(CONFIG_64BIT))
3823 			return -ENXIO;
3824 		fallthrough;
3825 	case SNDRV_PCM_MMAP_OFFSET_STATUS_NEW:
3826 		if (!pcm_status_mmap_allowed(pcm_file))
3827 			return -ENXIO;
3828 		return snd_pcm_mmap_status(substream, file, area);
3829 	case SNDRV_PCM_MMAP_OFFSET_CONTROL_OLD:
3830 		if (pcm_file->no_compat_mmap || !IS_ENABLED(CONFIG_64BIT))
3831 			return -ENXIO;
3832 		fallthrough;
3833 	case SNDRV_PCM_MMAP_OFFSET_CONTROL_NEW:
3834 		if (!pcm_control_mmap_allowed(pcm_file))
3835 			return -ENXIO;
3836 		return snd_pcm_mmap_control(substream, file, area);
3837 	default:
3838 		return snd_pcm_mmap_data(substream, file, area);
3839 	}
3840 	return 0;
3841 }
3842 
3843 static int snd_pcm_fasync(int fd, struct file * file, int on)
3844 {
3845 	struct snd_pcm_file * pcm_file;
3846 	struct snd_pcm_substream *substream;
3847 	struct snd_pcm_runtime *runtime;
3848 
3849 	pcm_file = file->private_data;
3850 	substream = pcm_file->substream;
3851 	if (PCM_RUNTIME_CHECK(substream))
3852 		return -ENXIO;
3853 	runtime = substream->runtime;
3854 	return fasync_helper(fd, file, on, &runtime->fasync);
3855 }
3856 
3857 /*
3858  * ioctl32 compat
3859  */
3860 #ifdef CONFIG_COMPAT
3861 #include "pcm_compat.c"
3862 #else
3863 #define snd_pcm_ioctl_compat	NULL
3864 #endif
3865 
3866 /*
3867  *  To be removed helpers to keep binary compatibility
3868  */
3869 
3870 #ifdef CONFIG_SND_SUPPORT_OLD_API
3871 #define __OLD_TO_NEW_MASK(x) ((x&7)|((x&0x07fffff8)<<5))
3872 #define __NEW_TO_OLD_MASK(x) ((x&7)|((x&0xffffff00)>>5))
3873 
3874 static void snd_pcm_hw_convert_from_old_params(struct snd_pcm_hw_params *params,
3875 					       struct snd_pcm_hw_params_old *oparams)
3876 {
3877 	unsigned int i;
3878 
3879 	memset(params, 0, sizeof(*params));
3880 	params->flags = oparams->flags;
3881 	for (i = 0; i < ARRAY_SIZE(oparams->masks); i++)
3882 		params->masks[i].bits[0] = oparams->masks[i];
3883 	memcpy(params->intervals, oparams->intervals, sizeof(oparams->intervals));
3884 	params->rmask = __OLD_TO_NEW_MASK(oparams->rmask);
3885 	params->cmask = __OLD_TO_NEW_MASK(oparams->cmask);
3886 	params->info = oparams->info;
3887 	params->msbits = oparams->msbits;
3888 	params->rate_num = oparams->rate_num;
3889 	params->rate_den = oparams->rate_den;
3890 	params->fifo_size = oparams->fifo_size;
3891 }
3892 
3893 static void snd_pcm_hw_convert_to_old_params(struct snd_pcm_hw_params_old *oparams,
3894 					     struct snd_pcm_hw_params *params)
3895 {
3896 	unsigned int i;
3897 
3898 	memset(oparams, 0, sizeof(*oparams));
3899 	oparams->flags = params->flags;
3900 	for (i = 0; i < ARRAY_SIZE(oparams->masks); i++)
3901 		oparams->masks[i] = params->masks[i].bits[0];
3902 	memcpy(oparams->intervals, params->intervals, sizeof(oparams->intervals));
3903 	oparams->rmask = __NEW_TO_OLD_MASK(params->rmask);
3904 	oparams->cmask = __NEW_TO_OLD_MASK(params->cmask);
3905 	oparams->info = params->info;
3906 	oparams->msbits = params->msbits;
3907 	oparams->rate_num = params->rate_num;
3908 	oparams->rate_den = params->rate_den;
3909 	oparams->fifo_size = params->fifo_size;
3910 }
3911 
3912 static int snd_pcm_hw_refine_old_user(struct snd_pcm_substream *substream,
3913 				      struct snd_pcm_hw_params_old __user * _oparams)
3914 {
3915 	struct snd_pcm_hw_params *params;
3916 	struct snd_pcm_hw_params_old *oparams = NULL;
3917 	int err;
3918 
3919 	params = kmalloc(sizeof(*params), GFP_KERNEL);
3920 	if (!params)
3921 		return -ENOMEM;
3922 
3923 	oparams = memdup_user(_oparams, sizeof(*oparams));
3924 	if (IS_ERR(oparams)) {
3925 		err = PTR_ERR(oparams);
3926 		goto out;
3927 	}
3928 	snd_pcm_hw_convert_from_old_params(params, oparams);
3929 	err = snd_pcm_hw_refine(substream, params);
3930 	if (err < 0)
3931 		goto out_old;
3932 
3933 	err = fixup_unreferenced_params(substream, params);
3934 	if (err < 0)
3935 		goto out_old;
3936 
3937 	snd_pcm_hw_convert_to_old_params(oparams, params);
3938 	if (copy_to_user(_oparams, oparams, sizeof(*oparams)))
3939 		err = -EFAULT;
3940 out_old:
3941 	kfree(oparams);
3942 out:
3943 	kfree(params);
3944 	return err;
3945 }
3946 
3947 static int snd_pcm_hw_params_old_user(struct snd_pcm_substream *substream,
3948 				      struct snd_pcm_hw_params_old __user * _oparams)
3949 {
3950 	struct snd_pcm_hw_params *params;
3951 	struct snd_pcm_hw_params_old *oparams = NULL;
3952 	int err;
3953 
3954 	params = kmalloc(sizeof(*params), GFP_KERNEL);
3955 	if (!params)
3956 		return -ENOMEM;
3957 
3958 	oparams = memdup_user(_oparams, sizeof(*oparams));
3959 	if (IS_ERR(oparams)) {
3960 		err = PTR_ERR(oparams);
3961 		goto out;
3962 	}
3963 
3964 	snd_pcm_hw_convert_from_old_params(params, oparams);
3965 	err = snd_pcm_hw_params(substream, params);
3966 	if (err < 0)
3967 		goto out_old;
3968 
3969 	snd_pcm_hw_convert_to_old_params(oparams, params);
3970 	if (copy_to_user(_oparams, oparams, sizeof(*oparams)))
3971 		err = -EFAULT;
3972 out_old:
3973 	kfree(oparams);
3974 out:
3975 	kfree(params);
3976 	return err;
3977 }
3978 #endif /* CONFIG_SND_SUPPORT_OLD_API */
3979 
3980 #ifndef CONFIG_MMU
3981 static unsigned long snd_pcm_get_unmapped_area(struct file *file,
3982 					       unsigned long addr,
3983 					       unsigned long len,
3984 					       unsigned long pgoff,
3985 					       unsigned long flags)
3986 {
3987 	struct snd_pcm_file *pcm_file = file->private_data;
3988 	struct snd_pcm_substream *substream = pcm_file->substream;
3989 	struct snd_pcm_runtime *runtime = substream->runtime;
3990 	unsigned long offset = pgoff << PAGE_SHIFT;
3991 
3992 	switch (offset) {
3993 	case SNDRV_PCM_MMAP_OFFSET_STATUS_NEW:
3994 		return (unsigned long)runtime->status;
3995 	case SNDRV_PCM_MMAP_OFFSET_CONTROL_NEW:
3996 		return (unsigned long)runtime->control;
3997 	default:
3998 		return (unsigned long)runtime->dma_area + offset;
3999 	}
4000 }
4001 #else
4002 # define snd_pcm_get_unmapped_area NULL
4003 #endif
4004 
4005 /*
4006  *  Register section
4007  */
4008 
4009 const struct file_operations snd_pcm_f_ops[2] = {
4010 	{
4011 		.owner =		THIS_MODULE,
4012 		.write =		snd_pcm_write,
4013 		.write_iter =		snd_pcm_writev,
4014 		.open =			snd_pcm_playback_open,
4015 		.release =		snd_pcm_release,
4016 		.llseek =		no_llseek,
4017 		.poll =			snd_pcm_poll,
4018 		.unlocked_ioctl =	snd_pcm_ioctl,
4019 		.compat_ioctl = 	snd_pcm_ioctl_compat,
4020 		.mmap =			snd_pcm_mmap,
4021 		.fasync =		snd_pcm_fasync,
4022 		.get_unmapped_area =	snd_pcm_get_unmapped_area,
4023 	},
4024 	{
4025 		.owner =		THIS_MODULE,
4026 		.read =			snd_pcm_read,
4027 		.read_iter =		snd_pcm_readv,
4028 		.open =			snd_pcm_capture_open,
4029 		.release =		snd_pcm_release,
4030 		.llseek =		no_llseek,
4031 		.poll =			snd_pcm_poll,
4032 		.unlocked_ioctl =	snd_pcm_ioctl,
4033 		.compat_ioctl = 	snd_pcm_ioctl_compat,
4034 		.mmap =			snd_pcm_mmap,
4035 		.fasync =		snd_pcm_fasync,
4036 		.get_unmapped_area =	snd_pcm_get_unmapped_area,
4037 	}
4038 };
4039