xref: /openbmc/linux/sound/core/pcm_native.c (revision dbf563ee)
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_lock - 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 	strlcpy(info->id, pcm->id, sizeof(info->id));
213 	strlcpy(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 	strlcpy(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 three dependencies
386 		 * to SNDRV_PCM_HW_PARAM_XXXs for this rule. The fourth
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 static void snd_pcm_sync_stop(struct snd_pcm_substream *substream)
587 {
588 	if (substream->runtime->stop_operating) {
589 		substream->runtime->stop_operating = false;
590 		if (substream->ops->sync_stop)
591 			substream->ops->sync_stop(substream);
592 		else if (substream->pcm->card->sync_irq > 0)
593 			synchronize_irq(substream->pcm->card->sync_irq);
594 	}
595 }
596 
597 /**
598  * snd_pcm_hw_param_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);
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 		memset(runtime->dma_area, 0, runtime->dma_bytes);
760 
761 	snd_pcm_timer_resolution_change(substream);
762 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_SETUP);
763 
764 	if (cpu_latency_qos_request_active(&substream->latency_pm_qos_req))
765 		cpu_latency_qos_remove_request(&substream->latency_pm_qos_req);
766 	if ((usecs = period_to_usecs(runtime)) >= 0)
767 		cpu_latency_qos_add_request(&substream->latency_pm_qos_req,
768 					    usecs);
769 	return 0;
770  _error:
771 	/* hardware might be unusable from this time,
772 	   so we force application to retry to set
773 	   the correct hardware parameter settings */
774 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_OPEN);
775 	if (substream->ops->hw_free != NULL)
776 		substream->ops->hw_free(substream);
777 	if (substream->managed_buffer_alloc)
778 		snd_pcm_lib_free_pages(substream);
779 	return err;
780 }
781 
782 static int snd_pcm_hw_params_user(struct snd_pcm_substream *substream,
783 				  struct snd_pcm_hw_params __user * _params)
784 {
785 	struct snd_pcm_hw_params *params;
786 	int err;
787 
788 	params = memdup_user(_params, sizeof(*params));
789 	if (IS_ERR(params))
790 		return PTR_ERR(params);
791 
792 	err = snd_pcm_hw_params(substream, params);
793 	if (err < 0)
794 		goto end;
795 
796 	if (copy_to_user(_params, params, sizeof(*params)))
797 		err = -EFAULT;
798 end:
799 	kfree(params);
800 	return err;
801 }
802 
803 static int do_hw_free(struct snd_pcm_substream *substream)
804 {
805 	int result = 0;
806 
807 	snd_pcm_sync_stop(substream);
808 	if (substream->ops->hw_free)
809 		result = substream->ops->hw_free(substream);
810 	if (substream->managed_buffer_alloc)
811 		snd_pcm_lib_free_pages(substream);
812 	return result;
813 }
814 
815 static int snd_pcm_hw_free(struct snd_pcm_substream *substream)
816 {
817 	struct snd_pcm_runtime *runtime;
818 	int result;
819 
820 	if (PCM_RUNTIME_CHECK(substream))
821 		return -ENXIO;
822 	runtime = substream->runtime;
823 	snd_pcm_stream_lock_irq(substream);
824 	switch (runtime->status->state) {
825 	case SNDRV_PCM_STATE_SETUP:
826 	case SNDRV_PCM_STATE_PREPARED:
827 		break;
828 	default:
829 		snd_pcm_stream_unlock_irq(substream);
830 		return -EBADFD;
831 	}
832 	snd_pcm_stream_unlock_irq(substream);
833 	if (atomic_read(&substream->mmap_count))
834 		return -EBADFD;
835 	result = do_hw_free(substream);
836 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_OPEN);
837 	cpu_latency_qos_remove_request(&substream->latency_pm_qos_req);
838 	return result;
839 }
840 
841 static int snd_pcm_sw_params(struct snd_pcm_substream *substream,
842 			     struct snd_pcm_sw_params *params)
843 {
844 	struct snd_pcm_runtime *runtime;
845 	int err;
846 
847 	if (PCM_RUNTIME_CHECK(substream))
848 		return -ENXIO;
849 	runtime = substream->runtime;
850 	snd_pcm_stream_lock_irq(substream);
851 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
852 		snd_pcm_stream_unlock_irq(substream);
853 		return -EBADFD;
854 	}
855 	snd_pcm_stream_unlock_irq(substream);
856 
857 	if (params->tstamp_mode < 0 ||
858 	    params->tstamp_mode > SNDRV_PCM_TSTAMP_LAST)
859 		return -EINVAL;
860 	if (params->proto >= SNDRV_PROTOCOL_VERSION(2, 0, 12) &&
861 	    params->tstamp_type > SNDRV_PCM_TSTAMP_TYPE_LAST)
862 		return -EINVAL;
863 	if (params->avail_min == 0)
864 		return -EINVAL;
865 	if (params->silence_size >= runtime->boundary) {
866 		if (params->silence_threshold != 0)
867 			return -EINVAL;
868 	} else {
869 		if (params->silence_size > params->silence_threshold)
870 			return -EINVAL;
871 		if (params->silence_threshold > runtime->buffer_size)
872 			return -EINVAL;
873 	}
874 	err = 0;
875 	snd_pcm_stream_lock_irq(substream);
876 	runtime->tstamp_mode = params->tstamp_mode;
877 	if (params->proto >= SNDRV_PROTOCOL_VERSION(2, 0, 12))
878 		runtime->tstamp_type = params->tstamp_type;
879 	runtime->period_step = params->period_step;
880 	runtime->control->avail_min = params->avail_min;
881 	runtime->start_threshold = params->start_threshold;
882 	runtime->stop_threshold = params->stop_threshold;
883 	runtime->silence_threshold = params->silence_threshold;
884 	runtime->silence_size = params->silence_size;
885         params->boundary = runtime->boundary;
886 	if (snd_pcm_running(substream)) {
887 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
888 		    runtime->silence_size > 0)
889 			snd_pcm_playback_silence(substream, ULONG_MAX);
890 		err = snd_pcm_update_state(substream, runtime);
891 	}
892 	snd_pcm_stream_unlock_irq(substream);
893 	return err;
894 }
895 
896 static int snd_pcm_sw_params_user(struct snd_pcm_substream *substream,
897 				  struct snd_pcm_sw_params __user * _params)
898 {
899 	struct snd_pcm_sw_params params;
900 	int err;
901 	if (copy_from_user(&params, _params, sizeof(params)))
902 		return -EFAULT;
903 	err = snd_pcm_sw_params(substream, &params);
904 	if (copy_to_user(_params, &params, sizeof(params)))
905 		return -EFAULT;
906 	return err;
907 }
908 
909 static inline snd_pcm_uframes_t
910 snd_pcm_calc_delay(struct snd_pcm_substream *substream)
911 {
912 	snd_pcm_uframes_t delay;
913 
914 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
915 		delay = snd_pcm_playback_hw_avail(substream->runtime);
916 	else
917 		delay = snd_pcm_capture_avail(substream->runtime);
918 	return delay + substream->runtime->delay;
919 }
920 
921 int snd_pcm_status64(struct snd_pcm_substream *substream,
922 		     struct snd_pcm_status64 *status)
923 {
924 	struct snd_pcm_runtime *runtime = substream->runtime;
925 
926 	snd_pcm_stream_lock_irq(substream);
927 
928 	snd_pcm_unpack_audio_tstamp_config(status->audio_tstamp_data,
929 					&runtime->audio_tstamp_config);
930 
931 	/* backwards compatible behavior */
932 	if (runtime->audio_tstamp_config.type_requested ==
933 		SNDRV_PCM_AUDIO_TSTAMP_TYPE_COMPAT) {
934 		if (runtime->hw.info & SNDRV_PCM_INFO_HAS_WALL_CLOCK)
935 			runtime->audio_tstamp_config.type_requested =
936 				SNDRV_PCM_AUDIO_TSTAMP_TYPE_LINK;
937 		else
938 			runtime->audio_tstamp_config.type_requested =
939 				SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT;
940 		runtime->audio_tstamp_report.valid = 0;
941 	} else
942 		runtime->audio_tstamp_report.valid = 1;
943 
944 	status->state = runtime->status->state;
945 	status->suspended_state = runtime->status->suspended_state;
946 	if (status->state == SNDRV_PCM_STATE_OPEN)
947 		goto _end;
948 	status->trigger_tstamp_sec = runtime->trigger_tstamp.tv_sec;
949 	status->trigger_tstamp_nsec = runtime->trigger_tstamp.tv_nsec;
950 	if (snd_pcm_running(substream)) {
951 		snd_pcm_update_hw_ptr(substream);
952 		if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
953 			status->tstamp_sec = runtime->status->tstamp.tv_sec;
954 			status->tstamp_nsec =
955 				runtime->status->tstamp.tv_nsec;
956 			status->driver_tstamp_sec =
957 				runtime->driver_tstamp.tv_sec;
958 			status->driver_tstamp_nsec =
959 				runtime->driver_tstamp.tv_nsec;
960 			status->audio_tstamp_sec =
961 				runtime->status->audio_tstamp.tv_sec;
962 			status->audio_tstamp_nsec =
963 				runtime->status->audio_tstamp.tv_nsec;
964 			if (runtime->audio_tstamp_report.valid == 1)
965 				/* backwards compatibility, no report provided in COMPAT mode */
966 				snd_pcm_pack_audio_tstamp_report(&status->audio_tstamp_data,
967 								&status->audio_tstamp_accuracy,
968 								&runtime->audio_tstamp_report);
969 
970 			goto _tstamp_end;
971 		}
972 	} else {
973 		/* get tstamp only in fallback mode and only if enabled */
974 		if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
975 			struct timespec64 tstamp;
976 
977 			snd_pcm_gettime(runtime, &tstamp);
978 			status->tstamp_sec = tstamp.tv_sec;
979 			status->tstamp_nsec = tstamp.tv_nsec;
980 		}
981 	}
982  _tstamp_end:
983 	status->appl_ptr = runtime->control->appl_ptr;
984 	status->hw_ptr = runtime->status->hw_ptr;
985 	status->avail = snd_pcm_avail(substream);
986 	status->delay = snd_pcm_running(substream) ?
987 		snd_pcm_calc_delay(substream) : 0;
988 	status->avail_max = runtime->avail_max;
989 	status->overrange = runtime->overrange;
990 	runtime->avail_max = 0;
991 	runtime->overrange = 0;
992  _end:
993  	snd_pcm_stream_unlock_irq(substream);
994 	return 0;
995 }
996 
997 static int snd_pcm_status_user64(struct snd_pcm_substream *substream,
998 				 struct snd_pcm_status64 __user * _status,
999 				 bool ext)
1000 {
1001 	struct snd_pcm_status64 status;
1002 	int res;
1003 
1004 	memset(&status, 0, sizeof(status));
1005 	/*
1006 	 * with extension, parameters are read/write,
1007 	 * get audio_tstamp_data from user,
1008 	 * ignore rest of status structure
1009 	 */
1010 	if (ext && get_user(status.audio_tstamp_data,
1011 				(u32 __user *)(&_status->audio_tstamp_data)))
1012 		return -EFAULT;
1013 	res = snd_pcm_status64(substream, &status);
1014 	if (res < 0)
1015 		return res;
1016 	if (copy_to_user(_status, &status, sizeof(status)))
1017 		return -EFAULT;
1018 	return 0;
1019 }
1020 
1021 static int snd_pcm_status_user32(struct snd_pcm_substream *substream,
1022 				 struct snd_pcm_status32 __user * _status,
1023 				 bool ext)
1024 {
1025 	struct snd_pcm_status64 status64;
1026 	struct snd_pcm_status32 status32;
1027 	int res;
1028 
1029 	memset(&status64, 0, sizeof(status64));
1030 	memset(&status32, 0, sizeof(status32));
1031 	/*
1032 	 * with extension, parameters are read/write,
1033 	 * get audio_tstamp_data from user,
1034 	 * ignore rest of status structure
1035 	 */
1036 	if (ext && get_user(status64.audio_tstamp_data,
1037 			    (u32 __user *)(&_status->audio_tstamp_data)))
1038 		return -EFAULT;
1039 	res = snd_pcm_status64(substream, &status64);
1040 	if (res < 0)
1041 		return res;
1042 
1043 	status32 = (struct snd_pcm_status32) {
1044 		.state = status64.state,
1045 		.trigger_tstamp_sec = status64.trigger_tstamp_sec,
1046 		.trigger_tstamp_nsec = status64.trigger_tstamp_nsec,
1047 		.tstamp_sec = status64.tstamp_sec,
1048 		.tstamp_nsec = status64.tstamp_nsec,
1049 		.appl_ptr = status64.appl_ptr,
1050 		.hw_ptr = status64.hw_ptr,
1051 		.delay = status64.delay,
1052 		.avail = status64.avail,
1053 		.avail_max = status64.avail_max,
1054 		.overrange = status64.overrange,
1055 		.suspended_state = status64.suspended_state,
1056 		.audio_tstamp_data = status64.audio_tstamp_data,
1057 		.audio_tstamp_sec = status64.audio_tstamp_sec,
1058 		.audio_tstamp_nsec = status64.audio_tstamp_nsec,
1059 		.driver_tstamp_sec = status64.audio_tstamp_sec,
1060 		.driver_tstamp_nsec = status64.audio_tstamp_nsec,
1061 		.audio_tstamp_accuracy = status64.audio_tstamp_accuracy,
1062 	};
1063 
1064 	if (copy_to_user(_status, &status32, sizeof(status32)))
1065 		return -EFAULT;
1066 
1067 	return 0;
1068 }
1069 
1070 static int snd_pcm_channel_info(struct snd_pcm_substream *substream,
1071 				struct snd_pcm_channel_info * info)
1072 {
1073 	struct snd_pcm_runtime *runtime;
1074 	unsigned int channel;
1075 
1076 	channel = info->channel;
1077 	runtime = substream->runtime;
1078 	snd_pcm_stream_lock_irq(substream);
1079 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
1080 		snd_pcm_stream_unlock_irq(substream);
1081 		return -EBADFD;
1082 	}
1083 	snd_pcm_stream_unlock_irq(substream);
1084 	if (channel >= runtime->channels)
1085 		return -EINVAL;
1086 	memset(info, 0, sizeof(*info));
1087 	info->channel = channel;
1088 	return snd_pcm_ops_ioctl(substream, SNDRV_PCM_IOCTL1_CHANNEL_INFO, info);
1089 }
1090 
1091 static int snd_pcm_channel_info_user(struct snd_pcm_substream *substream,
1092 				     struct snd_pcm_channel_info __user * _info)
1093 {
1094 	struct snd_pcm_channel_info info;
1095 	int res;
1096 
1097 	if (copy_from_user(&info, _info, sizeof(info)))
1098 		return -EFAULT;
1099 	res = snd_pcm_channel_info(substream, &info);
1100 	if (res < 0)
1101 		return res;
1102 	if (copy_to_user(_info, &info, sizeof(info)))
1103 		return -EFAULT;
1104 	return 0;
1105 }
1106 
1107 static void snd_pcm_trigger_tstamp(struct snd_pcm_substream *substream)
1108 {
1109 	struct snd_pcm_runtime *runtime = substream->runtime;
1110 	if (runtime->trigger_master == NULL)
1111 		return;
1112 	if (runtime->trigger_master == substream) {
1113 		if (!runtime->trigger_tstamp_latched)
1114 			snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
1115 	} else {
1116 		snd_pcm_trigger_tstamp(runtime->trigger_master);
1117 		runtime->trigger_tstamp = runtime->trigger_master->runtime->trigger_tstamp;
1118 	}
1119 	runtime->trigger_master = NULL;
1120 }
1121 
1122 #define ACTION_ARG_IGNORE	(__force snd_pcm_state_t)0
1123 
1124 struct action_ops {
1125 	int (*pre_action)(struct snd_pcm_substream *substream,
1126 			  snd_pcm_state_t state);
1127 	int (*do_action)(struct snd_pcm_substream *substream,
1128 			 snd_pcm_state_t state);
1129 	void (*undo_action)(struct snd_pcm_substream *substream,
1130 			    snd_pcm_state_t state);
1131 	void (*post_action)(struct snd_pcm_substream *substream,
1132 			    snd_pcm_state_t state);
1133 };
1134 
1135 /*
1136  *  this functions is core for handling of linked stream
1137  *  Note: the stream state might be changed also on failure
1138  *  Note2: call with calling stream lock + link lock
1139  */
1140 static int snd_pcm_action_group(const struct action_ops *ops,
1141 				struct snd_pcm_substream *substream,
1142 				snd_pcm_state_t state,
1143 				bool do_lock)
1144 {
1145 	struct snd_pcm_substream *s = NULL;
1146 	struct snd_pcm_substream *s1;
1147 	int res = 0, depth = 1;
1148 
1149 	snd_pcm_group_for_each_entry(s, substream) {
1150 		if (do_lock && s != substream) {
1151 			if (s->pcm->nonatomic)
1152 				mutex_lock_nested(&s->self_group.mutex, depth);
1153 			else
1154 				spin_lock_nested(&s->self_group.lock, depth);
1155 			depth++;
1156 		}
1157 		res = ops->pre_action(s, state);
1158 		if (res < 0)
1159 			goto _unlock;
1160 	}
1161 	snd_pcm_group_for_each_entry(s, substream) {
1162 		res = ops->do_action(s, state);
1163 		if (res < 0) {
1164 			if (ops->undo_action) {
1165 				snd_pcm_group_for_each_entry(s1, substream) {
1166 					if (s1 == s) /* failed stream */
1167 						break;
1168 					ops->undo_action(s1, state);
1169 				}
1170 			}
1171 			s = NULL; /* unlock all */
1172 			goto _unlock;
1173 		}
1174 	}
1175 	snd_pcm_group_for_each_entry(s, substream) {
1176 		ops->post_action(s, state);
1177 	}
1178  _unlock:
1179 	if (do_lock) {
1180 		/* unlock streams */
1181 		snd_pcm_group_for_each_entry(s1, substream) {
1182 			if (s1 != substream) {
1183 				if (s1->pcm->nonatomic)
1184 					mutex_unlock(&s1->self_group.mutex);
1185 				else
1186 					spin_unlock(&s1->self_group.lock);
1187 			}
1188 			if (s1 == s)	/* end */
1189 				break;
1190 		}
1191 	}
1192 	return res;
1193 }
1194 
1195 /*
1196  *  Note: call with stream lock
1197  */
1198 static int snd_pcm_action_single(const struct action_ops *ops,
1199 				 struct snd_pcm_substream *substream,
1200 				 snd_pcm_state_t state)
1201 {
1202 	int res;
1203 
1204 	res = ops->pre_action(substream, state);
1205 	if (res < 0)
1206 		return res;
1207 	res = ops->do_action(substream, state);
1208 	if (res == 0)
1209 		ops->post_action(substream, state);
1210 	else if (ops->undo_action)
1211 		ops->undo_action(substream, state);
1212 	return res;
1213 }
1214 
1215 static void snd_pcm_group_assign(struct snd_pcm_substream *substream,
1216 				 struct snd_pcm_group *new_group)
1217 {
1218 	substream->group = new_group;
1219 	list_move(&substream->link_list, &new_group->substreams);
1220 }
1221 
1222 /*
1223  * Unref and unlock the group, but keep the stream lock;
1224  * when the group becomes empty and no longer referred, destroy itself
1225  */
1226 static void snd_pcm_group_unref(struct snd_pcm_group *group,
1227 				struct snd_pcm_substream *substream)
1228 {
1229 	bool do_free;
1230 
1231 	if (!group)
1232 		return;
1233 	do_free = refcount_dec_and_test(&group->refs);
1234 	snd_pcm_group_unlock(group, substream->pcm->nonatomic);
1235 	if (do_free)
1236 		kfree(group);
1237 }
1238 
1239 /*
1240  * Lock the group inside a stream lock and reference it;
1241  * return the locked group object, or NULL if not linked
1242  */
1243 static struct snd_pcm_group *
1244 snd_pcm_stream_group_ref(struct snd_pcm_substream *substream)
1245 {
1246 	bool nonatomic = substream->pcm->nonatomic;
1247 	struct snd_pcm_group *group;
1248 	bool trylock;
1249 
1250 	for (;;) {
1251 		if (!snd_pcm_stream_linked(substream))
1252 			return NULL;
1253 		group = substream->group;
1254 		/* block freeing the group object */
1255 		refcount_inc(&group->refs);
1256 
1257 		trylock = nonatomic ? mutex_trylock(&group->mutex) :
1258 			spin_trylock(&group->lock);
1259 		if (trylock)
1260 			break; /* OK */
1261 
1262 		/* re-lock for avoiding ABBA deadlock */
1263 		snd_pcm_stream_unlock(substream);
1264 		snd_pcm_group_lock(group, nonatomic);
1265 		snd_pcm_stream_lock(substream);
1266 
1267 		/* check the group again; the above opens a small race window */
1268 		if (substream->group == group)
1269 			break; /* OK */
1270 		/* group changed, try again */
1271 		snd_pcm_group_unref(group, substream);
1272 	}
1273 	return group;
1274 }
1275 
1276 /*
1277  *  Note: call with stream lock
1278  */
1279 static int snd_pcm_action(const struct action_ops *ops,
1280 			  struct snd_pcm_substream *substream,
1281 			  snd_pcm_state_t state)
1282 {
1283 	struct snd_pcm_group *group;
1284 	int res;
1285 
1286 	group = snd_pcm_stream_group_ref(substream);
1287 	if (group)
1288 		res = snd_pcm_action_group(ops, substream, state, true);
1289 	else
1290 		res = snd_pcm_action_single(ops, substream, state);
1291 	snd_pcm_group_unref(group, substream);
1292 	return res;
1293 }
1294 
1295 /*
1296  *  Note: don't use any locks before
1297  */
1298 static int snd_pcm_action_lock_irq(const struct action_ops *ops,
1299 				   struct snd_pcm_substream *substream,
1300 				   snd_pcm_state_t state)
1301 {
1302 	int res;
1303 
1304 	snd_pcm_stream_lock_irq(substream);
1305 	res = snd_pcm_action(ops, substream, state);
1306 	snd_pcm_stream_unlock_irq(substream);
1307 	return res;
1308 }
1309 
1310 /*
1311  */
1312 static int snd_pcm_action_nonatomic(const struct action_ops *ops,
1313 				    struct snd_pcm_substream *substream,
1314 				    snd_pcm_state_t state)
1315 {
1316 	int res;
1317 
1318 	/* Guarantee the group members won't change during non-atomic action */
1319 	down_read(&snd_pcm_link_rwsem);
1320 	if (snd_pcm_stream_linked(substream))
1321 		res = snd_pcm_action_group(ops, substream, state, false);
1322 	else
1323 		res = snd_pcm_action_single(ops, substream, state);
1324 	up_read(&snd_pcm_link_rwsem);
1325 	return res;
1326 }
1327 
1328 /*
1329  * start callbacks
1330  */
1331 static int snd_pcm_pre_start(struct snd_pcm_substream *substream,
1332 			     snd_pcm_state_t state)
1333 {
1334 	struct snd_pcm_runtime *runtime = substream->runtime;
1335 	if (runtime->status->state != SNDRV_PCM_STATE_PREPARED)
1336 		return -EBADFD;
1337 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
1338 	    !snd_pcm_playback_data(substream))
1339 		return -EPIPE;
1340 	runtime->trigger_tstamp_latched = false;
1341 	runtime->trigger_master = substream;
1342 	return 0;
1343 }
1344 
1345 static int snd_pcm_do_start(struct snd_pcm_substream *substream,
1346 			    snd_pcm_state_t state)
1347 {
1348 	if (substream->runtime->trigger_master != substream)
1349 		return 0;
1350 	return substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_START);
1351 }
1352 
1353 static void snd_pcm_undo_start(struct snd_pcm_substream *substream,
1354 			       snd_pcm_state_t state)
1355 {
1356 	if (substream->runtime->trigger_master == substream)
1357 		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_STOP);
1358 }
1359 
1360 static void snd_pcm_post_start(struct snd_pcm_substream *substream,
1361 			       snd_pcm_state_t state)
1362 {
1363 	struct snd_pcm_runtime *runtime = substream->runtime;
1364 	snd_pcm_trigger_tstamp(substream);
1365 	runtime->hw_ptr_jiffies = jiffies;
1366 	runtime->hw_ptr_buffer_jiffies = (runtime->buffer_size * HZ) /
1367 							    runtime->rate;
1368 	runtime->status->state = state;
1369 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
1370 	    runtime->silence_size > 0)
1371 		snd_pcm_playback_silence(substream, ULONG_MAX);
1372 	snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MSTART);
1373 }
1374 
1375 static const struct action_ops snd_pcm_action_start = {
1376 	.pre_action = snd_pcm_pre_start,
1377 	.do_action = snd_pcm_do_start,
1378 	.undo_action = snd_pcm_undo_start,
1379 	.post_action = snd_pcm_post_start
1380 };
1381 
1382 /**
1383  * snd_pcm_start - start all linked streams
1384  * @substream: the PCM substream instance
1385  *
1386  * Return: Zero if successful, or a negative error code.
1387  * The stream lock must be acquired before calling this function.
1388  */
1389 int snd_pcm_start(struct snd_pcm_substream *substream)
1390 {
1391 	return snd_pcm_action(&snd_pcm_action_start, substream,
1392 			      SNDRV_PCM_STATE_RUNNING);
1393 }
1394 
1395 /* take the stream lock and start the streams */
1396 static int snd_pcm_start_lock_irq(struct snd_pcm_substream *substream)
1397 {
1398 	return snd_pcm_action_lock_irq(&snd_pcm_action_start, substream,
1399 				       SNDRV_PCM_STATE_RUNNING);
1400 }
1401 
1402 /*
1403  * stop callbacks
1404  */
1405 static int snd_pcm_pre_stop(struct snd_pcm_substream *substream,
1406 			    snd_pcm_state_t state)
1407 {
1408 	struct snd_pcm_runtime *runtime = substream->runtime;
1409 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1410 		return -EBADFD;
1411 	runtime->trigger_master = substream;
1412 	return 0;
1413 }
1414 
1415 static int snd_pcm_do_stop(struct snd_pcm_substream *substream,
1416 			   snd_pcm_state_t state)
1417 {
1418 	if (substream->runtime->trigger_master == substream &&
1419 	    snd_pcm_running(substream))
1420 		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_STOP);
1421 	return 0; /* unconditonally stop all substreams */
1422 }
1423 
1424 static void snd_pcm_post_stop(struct snd_pcm_substream *substream,
1425 			      snd_pcm_state_t state)
1426 {
1427 	struct snd_pcm_runtime *runtime = substream->runtime;
1428 	if (runtime->status->state != state) {
1429 		snd_pcm_trigger_tstamp(substream);
1430 		runtime->status->state = state;
1431 		snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MSTOP);
1432 	}
1433 	runtime->stop_operating = true;
1434 	wake_up(&runtime->sleep);
1435 	wake_up(&runtime->tsleep);
1436 }
1437 
1438 static const struct action_ops snd_pcm_action_stop = {
1439 	.pre_action = snd_pcm_pre_stop,
1440 	.do_action = snd_pcm_do_stop,
1441 	.post_action = snd_pcm_post_stop
1442 };
1443 
1444 /**
1445  * snd_pcm_stop - try to stop all running streams in the substream group
1446  * @substream: the PCM substream instance
1447  * @state: PCM state after stopping the stream
1448  *
1449  * The state of each stream is then changed to the given state unconditionally.
1450  *
1451  * Return: Zero if successful, or a negative error code.
1452  */
1453 int snd_pcm_stop(struct snd_pcm_substream *substream, snd_pcm_state_t state)
1454 {
1455 	return snd_pcm_action(&snd_pcm_action_stop, substream, state);
1456 }
1457 EXPORT_SYMBOL(snd_pcm_stop);
1458 
1459 /**
1460  * snd_pcm_drain_done - stop the DMA only when the given stream is playback
1461  * @substream: the PCM substream
1462  *
1463  * After stopping, the state is changed to SETUP.
1464  * Unlike snd_pcm_stop(), this affects only the given stream.
1465  *
1466  * Return: Zero if succesful, or a negative error code.
1467  */
1468 int snd_pcm_drain_done(struct snd_pcm_substream *substream)
1469 {
1470 	return snd_pcm_action_single(&snd_pcm_action_stop, substream,
1471 				     SNDRV_PCM_STATE_SETUP);
1472 }
1473 
1474 /**
1475  * snd_pcm_stop_xrun - stop the running streams as XRUN
1476  * @substream: the PCM substream instance
1477  *
1478  * This stops the given running substream (and all linked substreams) as XRUN.
1479  * Unlike snd_pcm_stop(), this function takes the substream lock by itself.
1480  *
1481  * Return: Zero if successful, or a negative error code.
1482  */
1483 int snd_pcm_stop_xrun(struct snd_pcm_substream *substream)
1484 {
1485 	unsigned long flags;
1486 
1487 	snd_pcm_stream_lock_irqsave(substream, flags);
1488 	if (substream->runtime && snd_pcm_running(substream))
1489 		__snd_pcm_xrun(substream);
1490 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1491 	return 0;
1492 }
1493 EXPORT_SYMBOL_GPL(snd_pcm_stop_xrun);
1494 
1495 /*
1496  * pause callbacks: pass boolean (to start pause or resume) as state argument
1497  */
1498 #define pause_pushed(state)	(__force bool)(state)
1499 
1500 static int snd_pcm_pre_pause(struct snd_pcm_substream *substream,
1501 			     snd_pcm_state_t state)
1502 {
1503 	struct snd_pcm_runtime *runtime = substream->runtime;
1504 	if (!(runtime->info & SNDRV_PCM_INFO_PAUSE))
1505 		return -ENOSYS;
1506 	if (pause_pushed(state)) {
1507 		if (runtime->status->state != SNDRV_PCM_STATE_RUNNING)
1508 			return -EBADFD;
1509 	} else if (runtime->status->state != SNDRV_PCM_STATE_PAUSED)
1510 		return -EBADFD;
1511 	runtime->trigger_master = substream;
1512 	return 0;
1513 }
1514 
1515 static int snd_pcm_do_pause(struct snd_pcm_substream *substream,
1516 			    snd_pcm_state_t state)
1517 {
1518 	if (substream->runtime->trigger_master != substream)
1519 		return 0;
1520 	/* some drivers might use hw_ptr to recover from the pause -
1521 	   update the hw_ptr now */
1522 	if (pause_pushed(state))
1523 		snd_pcm_update_hw_ptr(substream);
1524 	/* The jiffies check in snd_pcm_update_hw_ptr*() is done by
1525 	 * a delta between the current jiffies, this gives a large enough
1526 	 * delta, effectively to skip the check once.
1527 	 */
1528 	substream->runtime->hw_ptr_jiffies = jiffies - HZ * 1000;
1529 	return substream->ops->trigger(substream,
1530 				       pause_pushed(state) ?
1531 				       SNDRV_PCM_TRIGGER_PAUSE_PUSH :
1532 				       SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
1533 }
1534 
1535 static void snd_pcm_undo_pause(struct snd_pcm_substream *substream,
1536 			       snd_pcm_state_t state)
1537 {
1538 	if (substream->runtime->trigger_master == substream)
1539 		substream->ops->trigger(substream,
1540 					pause_pushed(state) ?
1541 					SNDRV_PCM_TRIGGER_PAUSE_RELEASE :
1542 					SNDRV_PCM_TRIGGER_PAUSE_PUSH);
1543 }
1544 
1545 static void snd_pcm_post_pause(struct snd_pcm_substream *substream,
1546 			       snd_pcm_state_t state)
1547 {
1548 	struct snd_pcm_runtime *runtime = substream->runtime;
1549 	snd_pcm_trigger_tstamp(substream);
1550 	if (pause_pushed(state)) {
1551 		runtime->status->state = SNDRV_PCM_STATE_PAUSED;
1552 		snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MPAUSE);
1553 		wake_up(&runtime->sleep);
1554 		wake_up(&runtime->tsleep);
1555 	} else {
1556 		runtime->status->state = SNDRV_PCM_STATE_RUNNING;
1557 		snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MCONTINUE);
1558 	}
1559 }
1560 
1561 static const struct action_ops snd_pcm_action_pause = {
1562 	.pre_action = snd_pcm_pre_pause,
1563 	.do_action = snd_pcm_do_pause,
1564 	.undo_action = snd_pcm_undo_pause,
1565 	.post_action = snd_pcm_post_pause
1566 };
1567 
1568 /*
1569  * Push/release the pause for all linked streams.
1570  */
1571 static int snd_pcm_pause(struct snd_pcm_substream *substream, bool push)
1572 {
1573 	return snd_pcm_action(&snd_pcm_action_pause, substream,
1574 			      (__force snd_pcm_state_t)push);
1575 }
1576 
1577 static int snd_pcm_pause_lock_irq(struct snd_pcm_substream *substream,
1578 				  bool push)
1579 {
1580 	return snd_pcm_action_lock_irq(&snd_pcm_action_pause, substream,
1581 				       (__force snd_pcm_state_t)push);
1582 }
1583 
1584 #ifdef CONFIG_PM
1585 /* suspend callback: state argument ignored */
1586 
1587 static int snd_pcm_pre_suspend(struct snd_pcm_substream *substream,
1588 			       snd_pcm_state_t state)
1589 {
1590 	struct snd_pcm_runtime *runtime = substream->runtime;
1591 	switch (runtime->status->state) {
1592 	case SNDRV_PCM_STATE_SUSPENDED:
1593 		return -EBUSY;
1594 	/* unresumable PCM state; return -EBUSY for skipping suspend */
1595 	case SNDRV_PCM_STATE_OPEN:
1596 	case SNDRV_PCM_STATE_SETUP:
1597 	case SNDRV_PCM_STATE_DISCONNECTED:
1598 		return -EBUSY;
1599 	}
1600 	runtime->trigger_master = substream;
1601 	return 0;
1602 }
1603 
1604 static int snd_pcm_do_suspend(struct snd_pcm_substream *substream,
1605 			      snd_pcm_state_t state)
1606 {
1607 	struct snd_pcm_runtime *runtime = substream->runtime;
1608 	if (runtime->trigger_master != substream)
1609 		return 0;
1610 	if (! snd_pcm_running(substream))
1611 		return 0;
1612 	substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_SUSPEND);
1613 	return 0; /* suspend unconditionally */
1614 }
1615 
1616 static void snd_pcm_post_suspend(struct snd_pcm_substream *substream,
1617 				 snd_pcm_state_t state)
1618 {
1619 	struct snd_pcm_runtime *runtime = substream->runtime;
1620 	snd_pcm_trigger_tstamp(substream);
1621 	runtime->status->suspended_state = runtime->status->state;
1622 	runtime->status->state = SNDRV_PCM_STATE_SUSPENDED;
1623 	snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MSUSPEND);
1624 	wake_up(&runtime->sleep);
1625 	wake_up(&runtime->tsleep);
1626 }
1627 
1628 static const struct action_ops snd_pcm_action_suspend = {
1629 	.pre_action = snd_pcm_pre_suspend,
1630 	.do_action = snd_pcm_do_suspend,
1631 	.post_action = snd_pcm_post_suspend
1632 };
1633 
1634 /*
1635  * snd_pcm_suspend - trigger SUSPEND to all linked streams
1636  * @substream: the PCM substream
1637  *
1638  * After this call, all streams are changed to SUSPENDED state.
1639  *
1640  * Return: Zero if successful, or a negative error code.
1641  */
1642 static int snd_pcm_suspend(struct snd_pcm_substream *substream)
1643 {
1644 	int err;
1645 	unsigned long flags;
1646 
1647 	snd_pcm_stream_lock_irqsave(substream, flags);
1648 	err = snd_pcm_action(&snd_pcm_action_suspend, substream,
1649 			     ACTION_ARG_IGNORE);
1650 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1651 	return err;
1652 }
1653 
1654 /**
1655  * snd_pcm_suspend_all - trigger SUSPEND to all substreams in the given pcm
1656  * @pcm: the PCM instance
1657  *
1658  * After this call, all streams are changed to SUSPENDED state.
1659  *
1660  * Return: Zero if successful (or @pcm is %NULL), or a negative error code.
1661  */
1662 int snd_pcm_suspend_all(struct snd_pcm *pcm)
1663 {
1664 	struct snd_pcm_substream *substream;
1665 	int stream, err = 0;
1666 
1667 	if (! pcm)
1668 		return 0;
1669 
1670 	for (stream = 0; stream < 2; stream++) {
1671 		for (substream = pcm->streams[stream].substream;
1672 		     substream; substream = substream->next) {
1673 			/* FIXME: the open/close code should lock this as well */
1674 			if (substream->runtime == NULL)
1675 				continue;
1676 
1677 			/*
1678 			 * Skip BE dai link PCM's that are internal and may
1679 			 * not have their substream ops set.
1680 			 */
1681 			if (!substream->ops)
1682 				continue;
1683 
1684 			err = snd_pcm_suspend(substream);
1685 			if (err < 0 && err != -EBUSY)
1686 				return err;
1687 		}
1688 	}
1689 	return 0;
1690 }
1691 EXPORT_SYMBOL(snd_pcm_suspend_all);
1692 
1693 /* resume callbacks: state argument ignored */
1694 
1695 static int snd_pcm_pre_resume(struct snd_pcm_substream *substream,
1696 			      snd_pcm_state_t state)
1697 {
1698 	struct snd_pcm_runtime *runtime = substream->runtime;
1699 	if (!(runtime->info & SNDRV_PCM_INFO_RESUME))
1700 		return -ENOSYS;
1701 	runtime->trigger_master = substream;
1702 	return 0;
1703 }
1704 
1705 static int snd_pcm_do_resume(struct snd_pcm_substream *substream,
1706 			     snd_pcm_state_t state)
1707 {
1708 	struct snd_pcm_runtime *runtime = substream->runtime;
1709 	if (runtime->trigger_master != substream)
1710 		return 0;
1711 	/* DMA not running previously? */
1712 	if (runtime->status->suspended_state != SNDRV_PCM_STATE_RUNNING &&
1713 	    (runtime->status->suspended_state != SNDRV_PCM_STATE_DRAINING ||
1714 	     substream->stream != SNDRV_PCM_STREAM_PLAYBACK))
1715 		return 0;
1716 	return substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_RESUME);
1717 }
1718 
1719 static void snd_pcm_undo_resume(struct snd_pcm_substream *substream,
1720 				snd_pcm_state_t state)
1721 {
1722 	if (substream->runtime->trigger_master == substream &&
1723 	    snd_pcm_running(substream))
1724 		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_SUSPEND);
1725 }
1726 
1727 static void snd_pcm_post_resume(struct snd_pcm_substream *substream,
1728 				snd_pcm_state_t state)
1729 {
1730 	struct snd_pcm_runtime *runtime = substream->runtime;
1731 	snd_pcm_trigger_tstamp(substream);
1732 	runtime->status->state = runtime->status->suspended_state;
1733 	snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MRESUME);
1734 	snd_pcm_sync_stop(substream);
1735 }
1736 
1737 static const struct action_ops snd_pcm_action_resume = {
1738 	.pre_action = snd_pcm_pre_resume,
1739 	.do_action = snd_pcm_do_resume,
1740 	.undo_action = snd_pcm_undo_resume,
1741 	.post_action = snd_pcm_post_resume
1742 };
1743 
1744 static int snd_pcm_resume(struct snd_pcm_substream *substream)
1745 {
1746 	return snd_pcm_action_lock_irq(&snd_pcm_action_resume, substream,
1747 				       ACTION_ARG_IGNORE);
1748 }
1749 
1750 #else
1751 
1752 static int snd_pcm_resume(struct snd_pcm_substream *substream)
1753 {
1754 	return -ENOSYS;
1755 }
1756 
1757 #endif /* CONFIG_PM */
1758 
1759 /*
1760  * xrun ioctl
1761  *
1762  * Change the RUNNING stream(s) to XRUN state.
1763  */
1764 static int snd_pcm_xrun(struct snd_pcm_substream *substream)
1765 {
1766 	struct snd_pcm_runtime *runtime = substream->runtime;
1767 	int result;
1768 
1769 	snd_pcm_stream_lock_irq(substream);
1770 	switch (runtime->status->state) {
1771 	case SNDRV_PCM_STATE_XRUN:
1772 		result = 0;	/* already there */
1773 		break;
1774 	case SNDRV_PCM_STATE_RUNNING:
1775 		__snd_pcm_xrun(substream);
1776 		result = 0;
1777 		break;
1778 	default:
1779 		result = -EBADFD;
1780 	}
1781 	snd_pcm_stream_unlock_irq(substream);
1782 	return result;
1783 }
1784 
1785 /*
1786  * reset ioctl
1787  */
1788 /* reset callbacks:  state argument ignored */
1789 static int snd_pcm_pre_reset(struct snd_pcm_substream *substream,
1790 			     snd_pcm_state_t state)
1791 {
1792 	struct snd_pcm_runtime *runtime = substream->runtime;
1793 	switch (runtime->status->state) {
1794 	case SNDRV_PCM_STATE_RUNNING:
1795 	case SNDRV_PCM_STATE_PREPARED:
1796 	case SNDRV_PCM_STATE_PAUSED:
1797 	case SNDRV_PCM_STATE_SUSPENDED:
1798 		return 0;
1799 	default:
1800 		return -EBADFD;
1801 	}
1802 }
1803 
1804 static int snd_pcm_do_reset(struct snd_pcm_substream *substream,
1805 			    snd_pcm_state_t state)
1806 {
1807 	struct snd_pcm_runtime *runtime = substream->runtime;
1808 	int err = snd_pcm_ops_ioctl(substream, SNDRV_PCM_IOCTL1_RESET, NULL);
1809 	if (err < 0)
1810 		return err;
1811 	runtime->hw_ptr_base = 0;
1812 	runtime->hw_ptr_interrupt = runtime->status->hw_ptr -
1813 		runtime->status->hw_ptr % runtime->period_size;
1814 	runtime->silence_start = runtime->status->hw_ptr;
1815 	runtime->silence_filled = 0;
1816 	return 0;
1817 }
1818 
1819 static void snd_pcm_post_reset(struct snd_pcm_substream *substream,
1820 			       snd_pcm_state_t state)
1821 {
1822 	struct snd_pcm_runtime *runtime = substream->runtime;
1823 	runtime->control->appl_ptr = runtime->status->hw_ptr;
1824 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
1825 	    runtime->silence_size > 0)
1826 		snd_pcm_playback_silence(substream, ULONG_MAX);
1827 }
1828 
1829 static const struct action_ops snd_pcm_action_reset = {
1830 	.pre_action = snd_pcm_pre_reset,
1831 	.do_action = snd_pcm_do_reset,
1832 	.post_action = snd_pcm_post_reset
1833 };
1834 
1835 static int snd_pcm_reset(struct snd_pcm_substream *substream)
1836 {
1837 	return snd_pcm_action_nonatomic(&snd_pcm_action_reset, substream,
1838 					ACTION_ARG_IGNORE);
1839 }
1840 
1841 /*
1842  * prepare ioctl
1843  */
1844 /* pass f_flags as state argument */
1845 static int snd_pcm_pre_prepare(struct snd_pcm_substream *substream,
1846 			       snd_pcm_state_t state)
1847 {
1848 	struct snd_pcm_runtime *runtime = substream->runtime;
1849 	int f_flags = (__force int)state;
1850 
1851 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN ||
1852 	    runtime->status->state == SNDRV_PCM_STATE_DISCONNECTED)
1853 		return -EBADFD;
1854 	if (snd_pcm_running(substream))
1855 		return -EBUSY;
1856 	substream->f_flags = f_flags;
1857 	return 0;
1858 }
1859 
1860 static int snd_pcm_do_prepare(struct snd_pcm_substream *substream,
1861 			      snd_pcm_state_t state)
1862 {
1863 	int err;
1864 	snd_pcm_sync_stop(substream);
1865 	err = substream->ops->prepare(substream);
1866 	if (err < 0)
1867 		return err;
1868 	return snd_pcm_do_reset(substream, state);
1869 }
1870 
1871 static void snd_pcm_post_prepare(struct snd_pcm_substream *substream,
1872 				 snd_pcm_state_t state)
1873 {
1874 	struct snd_pcm_runtime *runtime = substream->runtime;
1875 	runtime->control->appl_ptr = runtime->status->hw_ptr;
1876 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_PREPARED);
1877 }
1878 
1879 static const struct action_ops snd_pcm_action_prepare = {
1880 	.pre_action = snd_pcm_pre_prepare,
1881 	.do_action = snd_pcm_do_prepare,
1882 	.post_action = snd_pcm_post_prepare
1883 };
1884 
1885 /**
1886  * snd_pcm_prepare - prepare the PCM substream to be triggerable
1887  * @substream: the PCM substream instance
1888  * @file: file to refer f_flags
1889  *
1890  * Return: Zero if successful, or a negative error code.
1891  */
1892 static int snd_pcm_prepare(struct snd_pcm_substream *substream,
1893 			   struct file *file)
1894 {
1895 	int f_flags;
1896 
1897 	if (file)
1898 		f_flags = file->f_flags;
1899 	else
1900 		f_flags = substream->f_flags;
1901 
1902 	snd_pcm_stream_lock_irq(substream);
1903 	switch (substream->runtime->status->state) {
1904 	case SNDRV_PCM_STATE_PAUSED:
1905 		snd_pcm_pause(substream, false);
1906 		fallthrough;
1907 	case SNDRV_PCM_STATE_SUSPENDED:
1908 		snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
1909 		break;
1910 	}
1911 	snd_pcm_stream_unlock_irq(substream);
1912 
1913 	return snd_pcm_action_nonatomic(&snd_pcm_action_prepare,
1914 					substream,
1915 					(__force snd_pcm_state_t)f_flags);
1916 }
1917 
1918 /*
1919  * drain ioctl
1920  */
1921 
1922 /* drain init callbacks: state argument ignored */
1923 static int snd_pcm_pre_drain_init(struct snd_pcm_substream *substream,
1924 				  snd_pcm_state_t state)
1925 {
1926 	struct snd_pcm_runtime *runtime = substream->runtime;
1927 	switch (runtime->status->state) {
1928 	case SNDRV_PCM_STATE_OPEN:
1929 	case SNDRV_PCM_STATE_DISCONNECTED:
1930 	case SNDRV_PCM_STATE_SUSPENDED:
1931 		return -EBADFD;
1932 	}
1933 	runtime->trigger_master = substream;
1934 	return 0;
1935 }
1936 
1937 static int snd_pcm_do_drain_init(struct snd_pcm_substream *substream,
1938 				 snd_pcm_state_t state)
1939 {
1940 	struct snd_pcm_runtime *runtime = substream->runtime;
1941 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
1942 		switch (runtime->status->state) {
1943 		case SNDRV_PCM_STATE_PREPARED:
1944 			/* start playback stream if possible */
1945 			if (! snd_pcm_playback_empty(substream)) {
1946 				snd_pcm_do_start(substream, SNDRV_PCM_STATE_DRAINING);
1947 				snd_pcm_post_start(substream, SNDRV_PCM_STATE_DRAINING);
1948 			} else {
1949 				runtime->status->state = SNDRV_PCM_STATE_SETUP;
1950 			}
1951 			break;
1952 		case SNDRV_PCM_STATE_RUNNING:
1953 			runtime->status->state = SNDRV_PCM_STATE_DRAINING;
1954 			break;
1955 		case SNDRV_PCM_STATE_XRUN:
1956 			runtime->status->state = SNDRV_PCM_STATE_SETUP;
1957 			break;
1958 		default:
1959 			break;
1960 		}
1961 	} else {
1962 		/* stop running stream */
1963 		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING) {
1964 			snd_pcm_state_t new_state;
1965 
1966 			new_state = snd_pcm_capture_avail(runtime) > 0 ?
1967 				SNDRV_PCM_STATE_DRAINING : SNDRV_PCM_STATE_SETUP;
1968 			snd_pcm_do_stop(substream, new_state);
1969 			snd_pcm_post_stop(substream, new_state);
1970 		}
1971 	}
1972 
1973 	if (runtime->status->state == SNDRV_PCM_STATE_DRAINING &&
1974 	    runtime->trigger_master == substream &&
1975 	    (runtime->hw.info & SNDRV_PCM_INFO_DRAIN_TRIGGER))
1976 		return substream->ops->trigger(substream,
1977 					       SNDRV_PCM_TRIGGER_DRAIN);
1978 
1979 	return 0;
1980 }
1981 
1982 static void snd_pcm_post_drain_init(struct snd_pcm_substream *substream,
1983 				    snd_pcm_state_t state)
1984 {
1985 }
1986 
1987 static const struct action_ops snd_pcm_action_drain_init = {
1988 	.pre_action = snd_pcm_pre_drain_init,
1989 	.do_action = snd_pcm_do_drain_init,
1990 	.post_action = snd_pcm_post_drain_init
1991 };
1992 
1993 /*
1994  * Drain the stream(s).
1995  * When the substream is linked, sync until the draining of all playback streams
1996  * is finished.
1997  * After this call, all streams are supposed to be either SETUP or DRAINING
1998  * (capture only) state.
1999  */
2000 static int snd_pcm_drain(struct snd_pcm_substream *substream,
2001 			 struct file *file)
2002 {
2003 	struct snd_card *card;
2004 	struct snd_pcm_runtime *runtime;
2005 	struct snd_pcm_substream *s;
2006 	struct snd_pcm_group *group;
2007 	wait_queue_entry_t wait;
2008 	int result = 0;
2009 	int nonblock = 0;
2010 
2011 	card = substream->pcm->card;
2012 	runtime = substream->runtime;
2013 
2014 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2015 		return -EBADFD;
2016 
2017 	if (file) {
2018 		if (file->f_flags & O_NONBLOCK)
2019 			nonblock = 1;
2020 	} else if (substream->f_flags & O_NONBLOCK)
2021 		nonblock = 1;
2022 
2023 	snd_pcm_stream_lock_irq(substream);
2024 	/* resume pause */
2025 	if (runtime->status->state == SNDRV_PCM_STATE_PAUSED)
2026 		snd_pcm_pause(substream, false);
2027 
2028 	/* pre-start/stop - all running streams are changed to DRAINING state */
2029 	result = snd_pcm_action(&snd_pcm_action_drain_init, substream,
2030 				ACTION_ARG_IGNORE);
2031 	if (result < 0)
2032 		goto unlock;
2033 	/* in non-blocking, we don't wait in ioctl but let caller poll */
2034 	if (nonblock) {
2035 		result = -EAGAIN;
2036 		goto unlock;
2037 	}
2038 
2039 	for (;;) {
2040 		long tout;
2041 		struct snd_pcm_runtime *to_check;
2042 		if (signal_pending(current)) {
2043 			result = -ERESTARTSYS;
2044 			break;
2045 		}
2046 		/* find a substream to drain */
2047 		to_check = NULL;
2048 		group = snd_pcm_stream_group_ref(substream);
2049 		snd_pcm_group_for_each_entry(s, substream) {
2050 			if (s->stream != SNDRV_PCM_STREAM_PLAYBACK)
2051 				continue;
2052 			runtime = s->runtime;
2053 			if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
2054 				to_check = runtime;
2055 				break;
2056 			}
2057 		}
2058 		snd_pcm_group_unref(group, substream);
2059 		if (!to_check)
2060 			break; /* all drained */
2061 		init_waitqueue_entry(&wait, current);
2062 		set_current_state(TASK_INTERRUPTIBLE);
2063 		add_wait_queue(&to_check->sleep, &wait);
2064 		snd_pcm_stream_unlock_irq(substream);
2065 		if (runtime->no_period_wakeup)
2066 			tout = MAX_SCHEDULE_TIMEOUT;
2067 		else {
2068 			tout = 10;
2069 			if (runtime->rate) {
2070 				long t = runtime->period_size * 2 / runtime->rate;
2071 				tout = max(t, tout);
2072 			}
2073 			tout = msecs_to_jiffies(tout * 1000);
2074 		}
2075 		tout = schedule_timeout(tout);
2076 
2077 		snd_pcm_stream_lock_irq(substream);
2078 		group = snd_pcm_stream_group_ref(substream);
2079 		snd_pcm_group_for_each_entry(s, substream) {
2080 			if (s->runtime == to_check) {
2081 				remove_wait_queue(&to_check->sleep, &wait);
2082 				break;
2083 			}
2084 		}
2085 		snd_pcm_group_unref(group, substream);
2086 
2087 		if (card->shutdown) {
2088 			result = -ENODEV;
2089 			break;
2090 		}
2091 		if (tout == 0) {
2092 			if (substream->runtime->status->state == SNDRV_PCM_STATE_SUSPENDED)
2093 				result = -ESTRPIPE;
2094 			else {
2095 				dev_dbg(substream->pcm->card->dev,
2096 					"playback drain error (DMA or IRQ trouble?)\n");
2097 				snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2098 				result = -EIO;
2099 			}
2100 			break;
2101 		}
2102 	}
2103 
2104  unlock:
2105 	snd_pcm_stream_unlock_irq(substream);
2106 
2107 	return result;
2108 }
2109 
2110 /*
2111  * drop ioctl
2112  *
2113  * Immediately put all linked substreams into SETUP state.
2114  */
2115 static int snd_pcm_drop(struct snd_pcm_substream *substream)
2116 {
2117 	struct snd_pcm_runtime *runtime;
2118 	int result = 0;
2119 
2120 	if (PCM_RUNTIME_CHECK(substream))
2121 		return -ENXIO;
2122 	runtime = substream->runtime;
2123 
2124 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN ||
2125 	    runtime->status->state == SNDRV_PCM_STATE_DISCONNECTED)
2126 		return -EBADFD;
2127 
2128 	snd_pcm_stream_lock_irq(substream);
2129 	/* resume pause */
2130 	if (runtime->status->state == SNDRV_PCM_STATE_PAUSED)
2131 		snd_pcm_pause(substream, false);
2132 
2133 	snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2134 	/* runtime->control->appl_ptr = runtime->status->hw_ptr; */
2135 	snd_pcm_stream_unlock_irq(substream);
2136 
2137 	return result;
2138 }
2139 
2140 
2141 static bool is_pcm_file(struct file *file)
2142 {
2143 	struct inode *inode = file_inode(file);
2144 	struct snd_pcm *pcm;
2145 	unsigned int minor;
2146 
2147 	if (!S_ISCHR(inode->i_mode) || imajor(inode) != snd_major)
2148 		return false;
2149 	minor = iminor(inode);
2150 	pcm = snd_lookup_minor_data(minor, SNDRV_DEVICE_TYPE_PCM_PLAYBACK);
2151 	if (!pcm)
2152 		pcm = snd_lookup_minor_data(minor, SNDRV_DEVICE_TYPE_PCM_CAPTURE);
2153 	if (!pcm)
2154 		return false;
2155 	snd_card_unref(pcm->card);
2156 	return true;
2157 }
2158 
2159 /*
2160  * PCM link handling
2161  */
2162 static int snd_pcm_link(struct snd_pcm_substream *substream, int fd)
2163 {
2164 	int res = 0;
2165 	struct snd_pcm_file *pcm_file;
2166 	struct snd_pcm_substream *substream1;
2167 	struct snd_pcm_group *group, *target_group;
2168 	bool nonatomic = substream->pcm->nonatomic;
2169 	struct fd f = fdget(fd);
2170 
2171 	if (!f.file)
2172 		return -EBADFD;
2173 	if (!is_pcm_file(f.file)) {
2174 		res = -EBADFD;
2175 		goto _badf;
2176 	}
2177 	pcm_file = f.file->private_data;
2178 	substream1 = pcm_file->substream;
2179 
2180 	if (substream == substream1) {
2181 		res = -EINVAL;
2182 		goto _badf;
2183 	}
2184 
2185 	group = kzalloc(sizeof(*group), GFP_KERNEL);
2186 	if (!group) {
2187 		res = -ENOMEM;
2188 		goto _nolock;
2189 	}
2190 	snd_pcm_group_init(group);
2191 
2192 	down_write(&snd_pcm_link_rwsem);
2193 	if (substream->runtime->status->state == SNDRV_PCM_STATE_OPEN ||
2194 	    substream->runtime->status->state != substream1->runtime->status->state ||
2195 	    substream->pcm->nonatomic != substream1->pcm->nonatomic) {
2196 		res = -EBADFD;
2197 		goto _end;
2198 	}
2199 	if (snd_pcm_stream_linked(substream1)) {
2200 		res = -EALREADY;
2201 		goto _end;
2202 	}
2203 
2204 	snd_pcm_stream_lock_irq(substream);
2205 	if (!snd_pcm_stream_linked(substream)) {
2206 		snd_pcm_group_assign(substream, group);
2207 		group = NULL; /* assigned, don't free this one below */
2208 	}
2209 	target_group = substream->group;
2210 	snd_pcm_stream_unlock_irq(substream);
2211 
2212 	snd_pcm_group_lock_irq(target_group, nonatomic);
2213 	snd_pcm_stream_lock_nested(substream1);
2214 	snd_pcm_group_assign(substream1, target_group);
2215 	refcount_inc(&target_group->refs);
2216 	snd_pcm_stream_unlock(substream1);
2217 	snd_pcm_group_unlock_irq(target_group, nonatomic);
2218  _end:
2219 	up_write(&snd_pcm_link_rwsem);
2220  _nolock:
2221 	kfree(group);
2222  _badf:
2223 	fdput(f);
2224 	return res;
2225 }
2226 
2227 static void relink_to_local(struct snd_pcm_substream *substream)
2228 {
2229 	snd_pcm_stream_lock_nested(substream);
2230 	snd_pcm_group_assign(substream, &substream->self_group);
2231 	snd_pcm_stream_unlock(substream);
2232 }
2233 
2234 static int snd_pcm_unlink(struct snd_pcm_substream *substream)
2235 {
2236 	struct snd_pcm_group *group;
2237 	bool nonatomic = substream->pcm->nonatomic;
2238 	bool do_free = false;
2239 	int res = 0;
2240 
2241 	down_write(&snd_pcm_link_rwsem);
2242 
2243 	if (!snd_pcm_stream_linked(substream)) {
2244 		res = -EALREADY;
2245 		goto _end;
2246 	}
2247 
2248 	group = substream->group;
2249 	snd_pcm_group_lock_irq(group, nonatomic);
2250 
2251 	relink_to_local(substream);
2252 	refcount_dec(&group->refs);
2253 
2254 	/* detach the last stream, too */
2255 	if (list_is_singular(&group->substreams)) {
2256 		relink_to_local(list_first_entry(&group->substreams,
2257 						 struct snd_pcm_substream,
2258 						 link_list));
2259 		do_free = refcount_dec_and_test(&group->refs);
2260 	}
2261 
2262 	snd_pcm_group_unlock_irq(group, nonatomic);
2263 	if (do_free)
2264 		kfree(group);
2265 
2266        _end:
2267 	up_write(&snd_pcm_link_rwsem);
2268 	return res;
2269 }
2270 
2271 /*
2272  * hw configurator
2273  */
2274 static int snd_pcm_hw_rule_mul(struct snd_pcm_hw_params *params,
2275 			       struct snd_pcm_hw_rule *rule)
2276 {
2277 	struct snd_interval t;
2278 	snd_interval_mul(hw_param_interval_c(params, rule->deps[0]),
2279 		     hw_param_interval_c(params, rule->deps[1]), &t);
2280 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2281 }
2282 
2283 static int snd_pcm_hw_rule_div(struct snd_pcm_hw_params *params,
2284 			       struct snd_pcm_hw_rule *rule)
2285 {
2286 	struct snd_interval t;
2287 	snd_interval_div(hw_param_interval_c(params, rule->deps[0]),
2288 		     hw_param_interval_c(params, rule->deps[1]), &t);
2289 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2290 }
2291 
2292 static int snd_pcm_hw_rule_muldivk(struct snd_pcm_hw_params *params,
2293 				   struct snd_pcm_hw_rule *rule)
2294 {
2295 	struct snd_interval t;
2296 	snd_interval_muldivk(hw_param_interval_c(params, rule->deps[0]),
2297 			 hw_param_interval_c(params, rule->deps[1]),
2298 			 (unsigned long) rule->private, &t);
2299 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2300 }
2301 
2302 static int snd_pcm_hw_rule_mulkdiv(struct snd_pcm_hw_params *params,
2303 				   struct snd_pcm_hw_rule *rule)
2304 {
2305 	struct snd_interval t;
2306 	snd_interval_mulkdiv(hw_param_interval_c(params, rule->deps[0]),
2307 			 (unsigned long) rule->private,
2308 			 hw_param_interval_c(params, rule->deps[1]), &t);
2309 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2310 }
2311 
2312 static int snd_pcm_hw_rule_format(struct snd_pcm_hw_params *params,
2313 				  struct snd_pcm_hw_rule *rule)
2314 {
2315 	snd_pcm_format_t k;
2316 	const struct snd_interval *i =
2317 				hw_param_interval_c(params, rule->deps[0]);
2318 	struct snd_mask m;
2319 	struct snd_mask *mask = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
2320 	snd_mask_any(&m);
2321 	pcm_for_each_format(k) {
2322 		int bits;
2323 		if (!snd_mask_test_format(mask, k))
2324 			continue;
2325 		bits = snd_pcm_format_physical_width(k);
2326 		if (bits <= 0)
2327 			continue; /* ignore invalid formats */
2328 		if ((unsigned)bits < i->min || (unsigned)bits > i->max)
2329 			snd_mask_reset(&m, (__force unsigned)k);
2330 	}
2331 	return snd_mask_refine(mask, &m);
2332 }
2333 
2334 static int snd_pcm_hw_rule_sample_bits(struct snd_pcm_hw_params *params,
2335 				       struct snd_pcm_hw_rule *rule)
2336 {
2337 	struct snd_interval t;
2338 	snd_pcm_format_t k;
2339 
2340 	t.min = UINT_MAX;
2341 	t.max = 0;
2342 	t.openmin = 0;
2343 	t.openmax = 0;
2344 	pcm_for_each_format(k) {
2345 		int bits;
2346 		if (!snd_mask_test_format(hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT), k))
2347 			continue;
2348 		bits = snd_pcm_format_physical_width(k);
2349 		if (bits <= 0)
2350 			continue; /* ignore invalid formats */
2351 		if (t.min > (unsigned)bits)
2352 			t.min = bits;
2353 		if (t.max < (unsigned)bits)
2354 			t.max = bits;
2355 	}
2356 	t.integer = 1;
2357 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2358 }
2359 
2360 #if SNDRV_PCM_RATE_5512 != 1 << 0 || SNDRV_PCM_RATE_192000 != 1 << 12
2361 #error "Change this table"
2362 #endif
2363 
2364 static const unsigned int rates[] = {
2365 	5512, 8000, 11025, 16000, 22050, 32000, 44100,
2366 	48000, 64000, 88200, 96000, 176400, 192000, 352800, 384000
2367 };
2368 
2369 const struct snd_pcm_hw_constraint_list snd_pcm_known_rates = {
2370 	.count = ARRAY_SIZE(rates),
2371 	.list = rates,
2372 };
2373 
2374 static int snd_pcm_hw_rule_rate(struct snd_pcm_hw_params *params,
2375 				struct snd_pcm_hw_rule *rule)
2376 {
2377 	struct snd_pcm_hardware *hw = rule->private;
2378 	return snd_interval_list(hw_param_interval(params, rule->var),
2379 				 snd_pcm_known_rates.count,
2380 				 snd_pcm_known_rates.list, hw->rates);
2381 }
2382 
2383 static int snd_pcm_hw_rule_buffer_bytes_max(struct snd_pcm_hw_params *params,
2384 					    struct snd_pcm_hw_rule *rule)
2385 {
2386 	struct snd_interval t;
2387 	struct snd_pcm_substream *substream = rule->private;
2388 	t.min = 0;
2389 	t.max = substream->buffer_bytes_max;
2390 	t.openmin = 0;
2391 	t.openmax = 0;
2392 	t.integer = 1;
2393 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2394 }
2395 
2396 static int snd_pcm_hw_constraints_init(struct snd_pcm_substream *substream)
2397 {
2398 	struct snd_pcm_runtime *runtime = substream->runtime;
2399 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
2400 	int k, err;
2401 
2402 	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++) {
2403 		snd_mask_any(constrs_mask(constrs, k));
2404 	}
2405 
2406 	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++) {
2407 		snd_interval_any(constrs_interval(constrs, k));
2408 	}
2409 
2410 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_CHANNELS));
2411 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_BUFFER_SIZE));
2412 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_BUFFER_BYTES));
2413 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_SAMPLE_BITS));
2414 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_FRAME_BITS));
2415 
2416 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
2417 				   snd_pcm_hw_rule_format, NULL,
2418 				   SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
2419 	if (err < 0)
2420 		return err;
2421 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
2422 				  snd_pcm_hw_rule_sample_bits, NULL,
2423 				  SNDRV_PCM_HW_PARAM_FORMAT,
2424 				  SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
2425 	if (err < 0)
2426 		return err;
2427 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
2428 				  snd_pcm_hw_rule_div, NULL,
2429 				  SNDRV_PCM_HW_PARAM_FRAME_BITS, SNDRV_PCM_HW_PARAM_CHANNELS, -1);
2430 	if (err < 0)
2431 		return err;
2432 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS,
2433 				  snd_pcm_hw_rule_mul, NULL,
2434 				  SNDRV_PCM_HW_PARAM_SAMPLE_BITS, SNDRV_PCM_HW_PARAM_CHANNELS, -1);
2435 	if (err < 0)
2436 		return err;
2437 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS,
2438 				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
2439 				  SNDRV_PCM_HW_PARAM_PERIOD_BYTES, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
2440 	if (err < 0)
2441 		return err;
2442 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS,
2443 				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
2444 				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, -1);
2445 	if (err < 0)
2446 		return err;
2447 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
2448 				  snd_pcm_hw_rule_div, NULL,
2449 				  SNDRV_PCM_HW_PARAM_FRAME_BITS, SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
2450 	if (err < 0)
2451 		return err;
2452 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
2453 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2454 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_PERIOD_TIME, -1);
2455 	if (err < 0)
2456 		return err;
2457 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
2458 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2459 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_BUFFER_TIME, -1);
2460 	if (err < 0)
2461 		return err;
2462 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIODS,
2463 				  snd_pcm_hw_rule_div, NULL,
2464 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
2465 	if (err < 0)
2466 		return err;
2467 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
2468 				  snd_pcm_hw_rule_div, NULL,
2469 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_PERIODS, -1);
2470 	if (err < 0)
2471 		return err;
2472 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
2473 				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
2474 				  SNDRV_PCM_HW_PARAM_PERIOD_BYTES, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2475 	if (err < 0)
2476 		return err;
2477 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
2478 				  snd_pcm_hw_rule_muldivk, (void*) 1000000,
2479 				  SNDRV_PCM_HW_PARAM_PERIOD_TIME, SNDRV_PCM_HW_PARAM_RATE, -1);
2480 	if (err < 0)
2481 		return err;
2482 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
2483 				  snd_pcm_hw_rule_mul, NULL,
2484 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_PERIODS, -1);
2485 	if (err < 0)
2486 		return err;
2487 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
2488 				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
2489 				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2490 	if (err < 0)
2491 		return err;
2492 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
2493 				  snd_pcm_hw_rule_muldivk, (void*) 1000000,
2494 				  SNDRV_PCM_HW_PARAM_BUFFER_TIME, SNDRV_PCM_HW_PARAM_RATE, -1);
2495 	if (err < 0)
2496 		return err;
2497 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
2498 				  snd_pcm_hw_rule_muldivk, (void*) 8,
2499 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2500 	if (err < 0)
2501 		return err;
2502 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
2503 				  snd_pcm_hw_rule_muldivk, (void*) 8,
2504 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2505 	if (err < 0)
2506 		return err;
2507 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
2508 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2509 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_RATE, -1);
2510 	if (err < 0)
2511 		return err;
2512 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_TIME,
2513 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2514 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_RATE, -1);
2515 	if (err < 0)
2516 		return err;
2517 	return 0;
2518 }
2519 
2520 static int snd_pcm_hw_constraints_complete(struct snd_pcm_substream *substream)
2521 {
2522 	struct snd_pcm_runtime *runtime = substream->runtime;
2523 	struct snd_pcm_hardware *hw = &runtime->hw;
2524 	int err;
2525 	unsigned int mask = 0;
2526 
2527         if (hw->info & SNDRV_PCM_INFO_INTERLEAVED)
2528 		mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_RW_INTERLEAVED);
2529         if (hw->info & SNDRV_PCM_INFO_NONINTERLEAVED)
2530 		mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_RW_NONINTERLEAVED);
2531 	if (hw_support_mmap(substream)) {
2532 		if (hw->info & SNDRV_PCM_INFO_INTERLEAVED)
2533 			mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_MMAP_INTERLEAVED);
2534 		if (hw->info & SNDRV_PCM_INFO_NONINTERLEAVED)
2535 			mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED);
2536 		if (hw->info & SNDRV_PCM_INFO_COMPLEX)
2537 			mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_MMAP_COMPLEX);
2538 	}
2539 	err = snd_pcm_hw_constraint_mask(runtime, SNDRV_PCM_HW_PARAM_ACCESS, mask);
2540 	if (err < 0)
2541 		return err;
2542 
2543 	err = snd_pcm_hw_constraint_mask64(runtime, SNDRV_PCM_HW_PARAM_FORMAT, hw->formats);
2544 	if (err < 0)
2545 		return err;
2546 
2547 	err = snd_pcm_hw_constraint_mask(runtime, SNDRV_PCM_HW_PARAM_SUBFORMAT,
2548 					 PARAM_MASK_BIT(SNDRV_PCM_SUBFORMAT_STD));
2549 	if (err < 0)
2550 		return err;
2551 
2552 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_CHANNELS,
2553 					   hw->channels_min, hw->channels_max);
2554 	if (err < 0)
2555 		return err;
2556 
2557 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_RATE,
2558 					   hw->rate_min, hw->rate_max);
2559 	if (err < 0)
2560 		return err;
2561 
2562 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
2563 					   hw->period_bytes_min, hw->period_bytes_max);
2564 	if (err < 0)
2565 		return err;
2566 
2567 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIODS,
2568 					   hw->periods_min, hw->periods_max);
2569 	if (err < 0)
2570 		return err;
2571 
2572 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
2573 					   hw->period_bytes_min, hw->buffer_bytes_max);
2574 	if (err < 0)
2575 		return err;
2576 
2577 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
2578 				  snd_pcm_hw_rule_buffer_bytes_max, substream,
2579 				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, -1);
2580 	if (err < 0)
2581 		return err;
2582 
2583 	/* FIXME: remove */
2584 	if (runtime->dma_bytes) {
2585 		err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 0, runtime->dma_bytes);
2586 		if (err < 0)
2587 			return err;
2588 	}
2589 
2590 	if (!(hw->rates & (SNDRV_PCM_RATE_KNOT | SNDRV_PCM_RATE_CONTINUOUS))) {
2591 		err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
2592 					  snd_pcm_hw_rule_rate, hw,
2593 					  SNDRV_PCM_HW_PARAM_RATE, -1);
2594 		if (err < 0)
2595 			return err;
2596 	}
2597 
2598 	/* FIXME: this belong to lowlevel */
2599 	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
2600 
2601 	return 0;
2602 }
2603 
2604 static void pcm_release_private(struct snd_pcm_substream *substream)
2605 {
2606 	if (snd_pcm_stream_linked(substream))
2607 		snd_pcm_unlink(substream);
2608 }
2609 
2610 void snd_pcm_release_substream(struct snd_pcm_substream *substream)
2611 {
2612 	substream->ref_count--;
2613 	if (substream->ref_count > 0)
2614 		return;
2615 
2616 	snd_pcm_drop(substream);
2617 	if (substream->hw_opened) {
2618 		if (substream->runtime->status->state != SNDRV_PCM_STATE_OPEN)
2619 			do_hw_free(substream);
2620 		substream->ops->close(substream);
2621 		substream->hw_opened = 0;
2622 	}
2623 	if (cpu_latency_qos_request_active(&substream->latency_pm_qos_req))
2624 		cpu_latency_qos_remove_request(&substream->latency_pm_qos_req);
2625 	if (substream->pcm_release) {
2626 		substream->pcm_release(substream);
2627 		substream->pcm_release = NULL;
2628 	}
2629 	snd_pcm_detach_substream(substream);
2630 }
2631 EXPORT_SYMBOL(snd_pcm_release_substream);
2632 
2633 int snd_pcm_open_substream(struct snd_pcm *pcm, int stream,
2634 			   struct file *file,
2635 			   struct snd_pcm_substream **rsubstream)
2636 {
2637 	struct snd_pcm_substream *substream;
2638 	int err;
2639 
2640 	err = snd_pcm_attach_substream(pcm, stream, file, &substream);
2641 	if (err < 0)
2642 		return err;
2643 	if (substream->ref_count > 1) {
2644 		*rsubstream = substream;
2645 		return 0;
2646 	}
2647 
2648 	err = snd_pcm_hw_constraints_init(substream);
2649 	if (err < 0) {
2650 		pcm_dbg(pcm, "snd_pcm_hw_constraints_init failed\n");
2651 		goto error;
2652 	}
2653 
2654 	if ((err = substream->ops->open(substream)) < 0)
2655 		goto error;
2656 
2657 	substream->hw_opened = 1;
2658 
2659 	err = snd_pcm_hw_constraints_complete(substream);
2660 	if (err < 0) {
2661 		pcm_dbg(pcm, "snd_pcm_hw_constraints_complete failed\n");
2662 		goto error;
2663 	}
2664 
2665 	*rsubstream = substream;
2666 	return 0;
2667 
2668  error:
2669 	snd_pcm_release_substream(substream);
2670 	return err;
2671 }
2672 EXPORT_SYMBOL(snd_pcm_open_substream);
2673 
2674 static int snd_pcm_open_file(struct file *file,
2675 			     struct snd_pcm *pcm,
2676 			     int stream)
2677 {
2678 	struct snd_pcm_file *pcm_file;
2679 	struct snd_pcm_substream *substream;
2680 	int err;
2681 
2682 	err = snd_pcm_open_substream(pcm, stream, file, &substream);
2683 	if (err < 0)
2684 		return err;
2685 
2686 	pcm_file = kzalloc(sizeof(*pcm_file), GFP_KERNEL);
2687 	if (pcm_file == NULL) {
2688 		snd_pcm_release_substream(substream);
2689 		return -ENOMEM;
2690 	}
2691 	pcm_file->substream = substream;
2692 	if (substream->ref_count == 1)
2693 		substream->pcm_release = pcm_release_private;
2694 	file->private_data = pcm_file;
2695 
2696 	return 0;
2697 }
2698 
2699 static int snd_pcm_playback_open(struct inode *inode, struct file *file)
2700 {
2701 	struct snd_pcm *pcm;
2702 	int err = nonseekable_open(inode, file);
2703 	if (err < 0)
2704 		return err;
2705 	pcm = snd_lookup_minor_data(iminor(inode),
2706 				    SNDRV_DEVICE_TYPE_PCM_PLAYBACK);
2707 	err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_PLAYBACK);
2708 	if (pcm)
2709 		snd_card_unref(pcm->card);
2710 	return err;
2711 }
2712 
2713 static int snd_pcm_capture_open(struct inode *inode, struct file *file)
2714 {
2715 	struct snd_pcm *pcm;
2716 	int err = nonseekable_open(inode, file);
2717 	if (err < 0)
2718 		return err;
2719 	pcm = snd_lookup_minor_data(iminor(inode),
2720 				    SNDRV_DEVICE_TYPE_PCM_CAPTURE);
2721 	err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_CAPTURE);
2722 	if (pcm)
2723 		snd_card_unref(pcm->card);
2724 	return err;
2725 }
2726 
2727 static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream)
2728 {
2729 	int err;
2730 	wait_queue_entry_t wait;
2731 
2732 	if (pcm == NULL) {
2733 		err = -ENODEV;
2734 		goto __error1;
2735 	}
2736 	err = snd_card_file_add(pcm->card, file);
2737 	if (err < 0)
2738 		goto __error1;
2739 	if (!try_module_get(pcm->card->module)) {
2740 		err = -EFAULT;
2741 		goto __error2;
2742 	}
2743 	init_waitqueue_entry(&wait, current);
2744 	add_wait_queue(&pcm->open_wait, &wait);
2745 	mutex_lock(&pcm->open_mutex);
2746 	while (1) {
2747 		err = snd_pcm_open_file(file, pcm, stream);
2748 		if (err >= 0)
2749 			break;
2750 		if (err == -EAGAIN) {
2751 			if (file->f_flags & O_NONBLOCK) {
2752 				err = -EBUSY;
2753 				break;
2754 			}
2755 		} else
2756 			break;
2757 		set_current_state(TASK_INTERRUPTIBLE);
2758 		mutex_unlock(&pcm->open_mutex);
2759 		schedule();
2760 		mutex_lock(&pcm->open_mutex);
2761 		if (pcm->card->shutdown) {
2762 			err = -ENODEV;
2763 			break;
2764 		}
2765 		if (signal_pending(current)) {
2766 			err = -ERESTARTSYS;
2767 			break;
2768 		}
2769 	}
2770 	remove_wait_queue(&pcm->open_wait, &wait);
2771 	mutex_unlock(&pcm->open_mutex);
2772 	if (err < 0)
2773 		goto __error;
2774 	return err;
2775 
2776       __error:
2777 	module_put(pcm->card->module);
2778       __error2:
2779       	snd_card_file_remove(pcm->card, file);
2780       __error1:
2781       	return err;
2782 }
2783 
2784 static int snd_pcm_release(struct inode *inode, struct file *file)
2785 {
2786 	struct snd_pcm *pcm;
2787 	struct snd_pcm_substream *substream;
2788 	struct snd_pcm_file *pcm_file;
2789 
2790 	pcm_file = file->private_data;
2791 	substream = pcm_file->substream;
2792 	if (snd_BUG_ON(!substream))
2793 		return -ENXIO;
2794 	pcm = substream->pcm;
2795 	mutex_lock(&pcm->open_mutex);
2796 	snd_pcm_release_substream(substream);
2797 	kfree(pcm_file);
2798 	mutex_unlock(&pcm->open_mutex);
2799 	wake_up(&pcm->open_wait);
2800 	module_put(pcm->card->module);
2801 	snd_card_file_remove(pcm->card, file);
2802 	return 0;
2803 }
2804 
2805 /* check and update PCM state; return 0 or a negative error
2806  * call this inside PCM lock
2807  */
2808 static int do_pcm_hwsync(struct snd_pcm_substream *substream)
2809 {
2810 	switch (substream->runtime->status->state) {
2811 	case SNDRV_PCM_STATE_DRAINING:
2812 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
2813 			return -EBADFD;
2814 		fallthrough;
2815 	case SNDRV_PCM_STATE_RUNNING:
2816 		return snd_pcm_update_hw_ptr(substream);
2817 	case SNDRV_PCM_STATE_PREPARED:
2818 	case SNDRV_PCM_STATE_PAUSED:
2819 		return 0;
2820 	case SNDRV_PCM_STATE_SUSPENDED:
2821 		return -ESTRPIPE;
2822 	case SNDRV_PCM_STATE_XRUN:
2823 		return -EPIPE;
2824 	default:
2825 		return -EBADFD;
2826 	}
2827 }
2828 
2829 /* increase the appl_ptr; returns the processed frames or a negative error */
2830 static snd_pcm_sframes_t forward_appl_ptr(struct snd_pcm_substream *substream,
2831 					  snd_pcm_uframes_t frames,
2832 					   snd_pcm_sframes_t avail)
2833 {
2834 	struct snd_pcm_runtime *runtime = substream->runtime;
2835 	snd_pcm_sframes_t appl_ptr;
2836 	int ret;
2837 
2838 	if (avail <= 0)
2839 		return 0;
2840 	if (frames > (snd_pcm_uframes_t)avail)
2841 		frames = avail;
2842 	appl_ptr = runtime->control->appl_ptr + frames;
2843 	if (appl_ptr >= (snd_pcm_sframes_t)runtime->boundary)
2844 		appl_ptr -= runtime->boundary;
2845 	ret = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2846 	return ret < 0 ? ret : frames;
2847 }
2848 
2849 /* decrease the appl_ptr; returns the processed frames or zero for error */
2850 static snd_pcm_sframes_t rewind_appl_ptr(struct snd_pcm_substream *substream,
2851 					 snd_pcm_uframes_t frames,
2852 					 snd_pcm_sframes_t avail)
2853 {
2854 	struct snd_pcm_runtime *runtime = substream->runtime;
2855 	snd_pcm_sframes_t appl_ptr;
2856 	int ret;
2857 
2858 	if (avail <= 0)
2859 		return 0;
2860 	if (frames > (snd_pcm_uframes_t)avail)
2861 		frames = avail;
2862 	appl_ptr = runtime->control->appl_ptr - frames;
2863 	if (appl_ptr < 0)
2864 		appl_ptr += runtime->boundary;
2865 	ret = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2866 	/* NOTE: we return zero for errors because PulseAudio gets depressed
2867 	 * upon receiving an error from rewind ioctl and stops processing
2868 	 * any longer.  Returning zero means that no rewind is done, so
2869 	 * it's not absolutely wrong to answer like that.
2870 	 */
2871 	return ret < 0 ? 0 : frames;
2872 }
2873 
2874 static snd_pcm_sframes_t snd_pcm_rewind(struct snd_pcm_substream *substream,
2875 					snd_pcm_uframes_t frames)
2876 {
2877 	snd_pcm_sframes_t ret;
2878 
2879 	if (frames == 0)
2880 		return 0;
2881 
2882 	snd_pcm_stream_lock_irq(substream);
2883 	ret = do_pcm_hwsync(substream);
2884 	if (!ret)
2885 		ret = rewind_appl_ptr(substream, frames,
2886 				      snd_pcm_hw_avail(substream));
2887 	snd_pcm_stream_unlock_irq(substream);
2888 	return ret;
2889 }
2890 
2891 static snd_pcm_sframes_t snd_pcm_forward(struct snd_pcm_substream *substream,
2892 					 snd_pcm_uframes_t frames)
2893 {
2894 	snd_pcm_sframes_t ret;
2895 
2896 	if (frames == 0)
2897 		return 0;
2898 
2899 	snd_pcm_stream_lock_irq(substream);
2900 	ret = do_pcm_hwsync(substream);
2901 	if (!ret)
2902 		ret = forward_appl_ptr(substream, frames,
2903 				       snd_pcm_avail(substream));
2904 	snd_pcm_stream_unlock_irq(substream);
2905 	return ret;
2906 }
2907 
2908 static int snd_pcm_hwsync(struct snd_pcm_substream *substream)
2909 {
2910 	int err;
2911 
2912 	snd_pcm_stream_lock_irq(substream);
2913 	err = do_pcm_hwsync(substream);
2914 	snd_pcm_stream_unlock_irq(substream);
2915 	return err;
2916 }
2917 
2918 static int snd_pcm_delay(struct snd_pcm_substream *substream,
2919 			 snd_pcm_sframes_t *delay)
2920 {
2921 	int err;
2922 	snd_pcm_sframes_t n = 0;
2923 
2924 	snd_pcm_stream_lock_irq(substream);
2925 	err = do_pcm_hwsync(substream);
2926 	if (!err)
2927 		n = snd_pcm_calc_delay(substream);
2928 	snd_pcm_stream_unlock_irq(substream);
2929 	if (!err)
2930 		*delay = n;
2931 	return err;
2932 }
2933 
2934 static int snd_pcm_sync_ptr(struct snd_pcm_substream *substream,
2935 			    struct snd_pcm_sync_ptr __user *_sync_ptr)
2936 {
2937 	struct snd_pcm_runtime *runtime = substream->runtime;
2938 	struct snd_pcm_sync_ptr sync_ptr;
2939 	volatile struct snd_pcm_mmap_status *status;
2940 	volatile struct snd_pcm_mmap_control *control;
2941 	int err;
2942 
2943 	memset(&sync_ptr, 0, sizeof(sync_ptr));
2944 	if (get_user(sync_ptr.flags, (unsigned __user *)&(_sync_ptr->flags)))
2945 		return -EFAULT;
2946 	if (copy_from_user(&sync_ptr.c.control, &(_sync_ptr->c.control), sizeof(struct snd_pcm_mmap_control)))
2947 		return -EFAULT;
2948 	status = runtime->status;
2949 	control = runtime->control;
2950 	if (sync_ptr.flags & SNDRV_PCM_SYNC_PTR_HWSYNC) {
2951 		err = snd_pcm_hwsync(substream);
2952 		if (err < 0)
2953 			return err;
2954 	}
2955 	snd_pcm_stream_lock_irq(substream);
2956 	if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_APPL)) {
2957 		err = pcm_lib_apply_appl_ptr(substream,
2958 					     sync_ptr.c.control.appl_ptr);
2959 		if (err < 0) {
2960 			snd_pcm_stream_unlock_irq(substream);
2961 			return err;
2962 		}
2963 	} else {
2964 		sync_ptr.c.control.appl_ptr = control->appl_ptr;
2965 	}
2966 	if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_AVAIL_MIN))
2967 		control->avail_min = sync_ptr.c.control.avail_min;
2968 	else
2969 		sync_ptr.c.control.avail_min = control->avail_min;
2970 	sync_ptr.s.status.state = status->state;
2971 	sync_ptr.s.status.hw_ptr = status->hw_ptr;
2972 	sync_ptr.s.status.tstamp = status->tstamp;
2973 	sync_ptr.s.status.suspended_state = status->suspended_state;
2974 	sync_ptr.s.status.audio_tstamp = status->audio_tstamp;
2975 	snd_pcm_stream_unlock_irq(substream);
2976 	if (copy_to_user(_sync_ptr, &sync_ptr, sizeof(sync_ptr)))
2977 		return -EFAULT;
2978 	return 0;
2979 }
2980 
2981 struct snd_pcm_mmap_status32 {
2982 	snd_pcm_state_t state;
2983 	s32 pad1;
2984 	u32 hw_ptr;
2985 	s32 tstamp_sec;
2986 	s32 tstamp_nsec;
2987 	snd_pcm_state_t suspended_state;
2988 	s32 audio_tstamp_sec;
2989 	s32 audio_tstamp_nsec;
2990 } __attribute__((packed));
2991 
2992 struct snd_pcm_mmap_control32 {
2993 	u32 appl_ptr;
2994 	u32 avail_min;
2995 };
2996 
2997 struct snd_pcm_sync_ptr32 {
2998 	u32 flags;
2999 	union {
3000 		struct snd_pcm_mmap_status32 status;
3001 		unsigned char reserved[64];
3002 	} s;
3003 	union {
3004 		struct snd_pcm_mmap_control32 control;
3005 		unsigned char reserved[64];
3006 	} c;
3007 } __attribute__((packed));
3008 
3009 /* recalcuate the boundary within 32bit */
3010 static snd_pcm_uframes_t recalculate_boundary(struct snd_pcm_runtime *runtime)
3011 {
3012 	snd_pcm_uframes_t boundary;
3013 
3014 	if (! runtime->buffer_size)
3015 		return 0;
3016 	boundary = runtime->buffer_size;
3017 	while (boundary * 2 <= 0x7fffffffUL - runtime->buffer_size)
3018 		boundary *= 2;
3019 	return boundary;
3020 }
3021 
3022 static int snd_pcm_ioctl_sync_ptr_compat(struct snd_pcm_substream *substream,
3023 					 struct snd_pcm_sync_ptr32 __user *src)
3024 {
3025 	struct snd_pcm_runtime *runtime = substream->runtime;
3026 	volatile struct snd_pcm_mmap_status *status;
3027 	volatile struct snd_pcm_mmap_control *control;
3028 	u32 sflags;
3029 	struct snd_pcm_mmap_control scontrol;
3030 	struct snd_pcm_mmap_status sstatus;
3031 	snd_pcm_uframes_t boundary;
3032 	int err;
3033 
3034 	if (snd_BUG_ON(!runtime))
3035 		return -EINVAL;
3036 
3037 	if (get_user(sflags, &src->flags) ||
3038 	    get_user(scontrol.appl_ptr, &src->c.control.appl_ptr) ||
3039 	    get_user(scontrol.avail_min, &src->c.control.avail_min))
3040 		return -EFAULT;
3041 	if (sflags & SNDRV_PCM_SYNC_PTR_HWSYNC) {
3042 		err = snd_pcm_hwsync(substream);
3043 		if (err < 0)
3044 			return err;
3045 	}
3046 	status = runtime->status;
3047 	control = runtime->control;
3048 	boundary = recalculate_boundary(runtime);
3049 	if (! boundary)
3050 		boundary = 0x7fffffff;
3051 	snd_pcm_stream_lock_irq(substream);
3052 	/* FIXME: we should consider the boundary for the sync from app */
3053 	if (!(sflags & SNDRV_PCM_SYNC_PTR_APPL))
3054 		control->appl_ptr = scontrol.appl_ptr;
3055 	else
3056 		scontrol.appl_ptr = control->appl_ptr % boundary;
3057 	if (!(sflags & SNDRV_PCM_SYNC_PTR_AVAIL_MIN))
3058 		control->avail_min = scontrol.avail_min;
3059 	else
3060 		scontrol.avail_min = control->avail_min;
3061 	sstatus.state = status->state;
3062 	sstatus.hw_ptr = status->hw_ptr % boundary;
3063 	sstatus.tstamp = status->tstamp;
3064 	sstatus.suspended_state = status->suspended_state;
3065 	sstatus.audio_tstamp = status->audio_tstamp;
3066 	snd_pcm_stream_unlock_irq(substream);
3067 	if (put_user(sstatus.state, &src->s.status.state) ||
3068 	    put_user(sstatus.hw_ptr, &src->s.status.hw_ptr) ||
3069 	    put_user(sstatus.tstamp.tv_sec, &src->s.status.tstamp_sec) ||
3070 	    put_user(sstatus.tstamp.tv_nsec, &src->s.status.tstamp_nsec) ||
3071 	    put_user(sstatus.suspended_state, &src->s.status.suspended_state) ||
3072 	    put_user(sstatus.audio_tstamp.tv_sec, &src->s.status.audio_tstamp_sec) ||
3073 	    put_user(sstatus.audio_tstamp.tv_nsec, &src->s.status.audio_tstamp_nsec) ||
3074 	    put_user(scontrol.appl_ptr, &src->c.control.appl_ptr) ||
3075 	    put_user(scontrol.avail_min, &src->c.control.avail_min))
3076 		return -EFAULT;
3077 
3078 	return 0;
3079 }
3080 #define __SNDRV_PCM_IOCTL_SYNC_PTR32 _IOWR('A', 0x23, struct snd_pcm_sync_ptr32)
3081 
3082 static int snd_pcm_tstamp(struct snd_pcm_substream *substream, int __user *_arg)
3083 {
3084 	struct snd_pcm_runtime *runtime = substream->runtime;
3085 	int arg;
3086 
3087 	if (get_user(arg, _arg))
3088 		return -EFAULT;
3089 	if (arg < 0 || arg > SNDRV_PCM_TSTAMP_TYPE_LAST)
3090 		return -EINVAL;
3091 	runtime->tstamp_type = arg;
3092 	return 0;
3093 }
3094 
3095 static int snd_pcm_xferi_frames_ioctl(struct snd_pcm_substream *substream,
3096 				      struct snd_xferi __user *_xferi)
3097 {
3098 	struct snd_xferi xferi;
3099 	struct snd_pcm_runtime *runtime = substream->runtime;
3100 	snd_pcm_sframes_t result;
3101 
3102 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3103 		return -EBADFD;
3104 	if (put_user(0, &_xferi->result))
3105 		return -EFAULT;
3106 	if (copy_from_user(&xferi, _xferi, sizeof(xferi)))
3107 		return -EFAULT;
3108 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
3109 		result = snd_pcm_lib_write(substream, xferi.buf, xferi.frames);
3110 	else
3111 		result = snd_pcm_lib_read(substream, xferi.buf, xferi.frames);
3112 	if (put_user(result, &_xferi->result))
3113 		return -EFAULT;
3114 	return result < 0 ? result : 0;
3115 }
3116 
3117 static int snd_pcm_xfern_frames_ioctl(struct snd_pcm_substream *substream,
3118 				      struct snd_xfern __user *_xfern)
3119 {
3120 	struct snd_xfern xfern;
3121 	struct snd_pcm_runtime *runtime = substream->runtime;
3122 	void *bufs;
3123 	snd_pcm_sframes_t result;
3124 
3125 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3126 		return -EBADFD;
3127 	if (runtime->channels > 128)
3128 		return -EINVAL;
3129 	if (put_user(0, &_xfern->result))
3130 		return -EFAULT;
3131 	if (copy_from_user(&xfern, _xfern, sizeof(xfern)))
3132 		return -EFAULT;
3133 
3134 	bufs = memdup_user(xfern.bufs, sizeof(void *) * runtime->channels);
3135 	if (IS_ERR(bufs))
3136 		return PTR_ERR(bufs);
3137 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
3138 		result = snd_pcm_lib_writev(substream, bufs, xfern.frames);
3139 	else
3140 		result = snd_pcm_lib_readv(substream, bufs, xfern.frames);
3141 	kfree(bufs);
3142 	if (put_user(result, &_xfern->result))
3143 		return -EFAULT;
3144 	return result < 0 ? result : 0;
3145 }
3146 
3147 static int snd_pcm_rewind_ioctl(struct snd_pcm_substream *substream,
3148 				snd_pcm_uframes_t __user *_frames)
3149 {
3150 	snd_pcm_uframes_t frames;
3151 	snd_pcm_sframes_t result;
3152 
3153 	if (get_user(frames, _frames))
3154 		return -EFAULT;
3155 	if (put_user(0, _frames))
3156 		return -EFAULT;
3157 	result = snd_pcm_rewind(substream, frames);
3158 	if (put_user(result, _frames))
3159 		return -EFAULT;
3160 	return result < 0 ? result : 0;
3161 }
3162 
3163 static int snd_pcm_forward_ioctl(struct snd_pcm_substream *substream,
3164 				 snd_pcm_uframes_t __user *_frames)
3165 {
3166 	snd_pcm_uframes_t frames;
3167 	snd_pcm_sframes_t result;
3168 
3169 	if (get_user(frames, _frames))
3170 		return -EFAULT;
3171 	if (put_user(0, _frames))
3172 		return -EFAULT;
3173 	result = snd_pcm_forward(substream, frames);
3174 	if (put_user(result, _frames))
3175 		return -EFAULT;
3176 	return result < 0 ? result : 0;
3177 }
3178 
3179 static int snd_pcm_common_ioctl(struct file *file,
3180 				 struct snd_pcm_substream *substream,
3181 				 unsigned int cmd, void __user *arg)
3182 {
3183 	struct snd_pcm_file *pcm_file = file->private_data;
3184 	int res;
3185 
3186 	if (PCM_RUNTIME_CHECK(substream))
3187 		return -ENXIO;
3188 
3189 	res = snd_power_wait(substream->pcm->card, SNDRV_CTL_POWER_D0);
3190 	if (res < 0)
3191 		return res;
3192 
3193 	switch (cmd) {
3194 	case SNDRV_PCM_IOCTL_PVERSION:
3195 		return put_user(SNDRV_PCM_VERSION, (int __user *)arg) ? -EFAULT : 0;
3196 	case SNDRV_PCM_IOCTL_INFO:
3197 		return snd_pcm_info_user(substream, arg);
3198 	case SNDRV_PCM_IOCTL_TSTAMP:	/* just for compatibility */
3199 		return 0;
3200 	case SNDRV_PCM_IOCTL_TTSTAMP:
3201 		return snd_pcm_tstamp(substream, arg);
3202 	case SNDRV_PCM_IOCTL_USER_PVERSION:
3203 		if (get_user(pcm_file->user_pversion,
3204 			     (unsigned int __user *)arg))
3205 			return -EFAULT;
3206 		return 0;
3207 	case SNDRV_PCM_IOCTL_HW_REFINE:
3208 		return snd_pcm_hw_refine_user(substream, arg);
3209 	case SNDRV_PCM_IOCTL_HW_PARAMS:
3210 		return snd_pcm_hw_params_user(substream, arg);
3211 	case SNDRV_PCM_IOCTL_HW_FREE:
3212 		return snd_pcm_hw_free(substream);
3213 	case SNDRV_PCM_IOCTL_SW_PARAMS:
3214 		return snd_pcm_sw_params_user(substream, arg);
3215 	case SNDRV_PCM_IOCTL_STATUS32:
3216 		return snd_pcm_status_user32(substream, arg, false);
3217 	case SNDRV_PCM_IOCTL_STATUS_EXT32:
3218 		return snd_pcm_status_user32(substream, arg, true);
3219 	case SNDRV_PCM_IOCTL_STATUS64:
3220 		return snd_pcm_status_user64(substream, arg, false);
3221 	case SNDRV_PCM_IOCTL_STATUS_EXT64:
3222 		return snd_pcm_status_user64(substream, arg, true);
3223 	case SNDRV_PCM_IOCTL_CHANNEL_INFO:
3224 		return snd_pcm_channel_info_user(substream, arg);
3225 	case SNDRV_PCM_IOCTL_PREPARE:
3226 		return snd_pcm_prepare(substream, file);
3227 	case SNDRV_PCM_IOCTL_RESET:
3228 		return snd_pcm_reset(substream);
3229 	case SNDRV_PCM_IOCTL_START:
3230 		return snd_pcm_start_lock_irq(substream);
3231 	case SNDRV_PCM_IOCTL_LINK:
3232 		return snd_pcm_link(substream, (int)(unsigned long) arg);
3233 	case SNDRV_PCM_IOCTL_UNLINK:
3234 		return snd_pcm_unlink(substream);
3235 	case SNDRV_PCM_IOCTL_RESUME:
3236 		return snd_pcm_resume(substream);
3237 	case SNDRV_PCM_IOCTL_XRUN:
3238 		return snd_pcm_xrun(substream);
3239 	case SNDRV_PCM_IOCTL_HWSYNC:
3240 		return snd_pcm_hwsync(substream);
3241 	case SNDRV_PCM_IOCTL_DELAY:
3242 	{
3243 		snd_pcm_sframes_t delay;
3244 		snd_pcm_sframes_t __user *res = arg;
3245 		int err;
3246 
3247 		err = snd_pcm_delay(substream, &delay);
3248 		if (err)
3249 			return err;
3250 		if (put_user(delay, res))
3251 			return -EFAULT;
3252 		return 0;
3253 	}
3254 	case __SNDRV_PCM_IOCTL_SYNC_PTR32:
3255 		return snd_pcm_ioctl_sync_ptr_compat(substream, arg);
3256 	case __SNDRV_PCM_IOCTL_SYNC_PTR64:
3257 		return snd_pcm_sync_ptr(substream, arg);
3258 #ifdef CONFIG_SND_SUPPORT_OLD_API
3259 	case SNDRV_PCM_IOCTL_HW_REFINE_OLD:
3260 		return snd_pcm_hw_refine_old_user(substream, arg);
3261 	case SNDRV_PCM_IOCTL_HW_PARAMS_OLD:
3262 		return snd_pcm_hw_params_old_user(substream, arg);
3263 #endif
3264 	case SNDRV_PCM_IOCTL_DRAIN:
3265 		return snd_pcm_drain(substream, file);
3266 	case SNDRV_PCM_IOCTL_DROP:
3267 		return snd_pcm_drop(substream);
3268 	case SNDRV_PCM_IOCTL_PAUSE:
3269 		return snd_pcm_pause_lock_irq(substream, (unsigned long)arg);
3270 	case SNDRV_PCM_IOCTL_WRITEI_FRAMES:
3271 	case SNDRV_PCM_IOCTL_READI_FRAMES:
3272 		return snd_pcm_xferi_frames_ioctl(substream, arg);
3273 	case SNDRV_PCM_IOCTL_WRITEN_FRAMES:
3274 	case SNDRV_PCM_IOCTL_READN_FRAMES:
3275 		return snd_pcm_xfern_frames_ioctl(substream, arg);
3276 	case SNDRV_PCM_IOCTL_REWIND:
3277 		return snd_pcm_rewind_ioctl(substream, arg);
3278 	case SNDRV_PCM_IOCTL_FORWARD:
3279 		return snd_pcm_forward_ioctl(substream, arg);
3280 	}
3281 	pcm_dbg(substream->pcm, "unknown ioctl = 0x%x\n", cmd);
3282 	return -ENOTTY;
3283 }
3284 
3285 static long snd_pcm_ioctl(struct file *file, unsigned int cmd,
3286 			  unsigned long arg)
3287 {
3288 	struct snd_pcm_file *pcm_file;
3289 
3290 	pcm_file = file->private_data;
3291 
3292 	if (((cmd >> 8) & 0xff) != 'A')
3293 		return -ENOTTY;
3294 
3295 	return snd_pcm_common_ioctl(file, pcm_file->substream, cmd,
3296 				     (void __user *)arg);
3297 }
3298 
3299 /**
3300  * snd_pcm_kernel_ioctl - Execute PCM ioctl in the kernel-space
3301  * @substream: PCM substream
3302  * @cmd: IOCTL cmd
3303  * @arg: IOCTL argument
3304  *
3305  * The function is provided primarily for OSS layer and USB gadget drivers,
3306  * and it allows only the limited set of ioctls (hw_params, sw_params,
3307  * prepare, start, drain, drop, forward).
3308  */
3309 int snd_pcm_kernel_ioctl(struct snd_pcm_substream *substream,
3310 			 unsigned int cmd, void *arg)
3311 {
3312 	snd_pcm_uframes_t *frames = arg;
3313 	snd_pcm_sframes_t result;
3314 
3315 	switch (cmd) {
3316 	case SNDRV_PCM_IOCTL_FORWARD:
3317 	{
3318 		/* provided only for OSS; capture-only and no value returned */
3319 		if (substream->stream != SNDRV_PCM_STREAM_CAPTURE)
3320 			return -EINVAL;
3321 		result = snd_pcm_forward(substream, *frames);
3322 		return result < 0 ? result : 0;
3323 	}
3324 	case SNDRV_PCM_IOCTL_HW_PARAMS:
3325 		return snd_pcm_hw_params(substream, arg);
3326 	case SNDRV_PCM_IOCTL_SW_PARAMS:
3327 		return snd_pcm_sw_params(substream, arg);
3328 	case SNDRV_PCM_IOCTL_PREPARE:
3329 		return snd_pcm_prepare(substream, NULL);
3330 	case SNDRV_PCM_IOCTL_START:
3331 		return snd_pcm_start_lock_irq(substream);
3332 	case SNDRV_PCM_IOCTL_DRAIN:
3333 		return snd_pcm_drain(substream, NULL);
3334 	case SNDRV_PCM_IOCTL_DROP:
3335 		return snd_pcm_drop(substream);
3336 	case SNDRV_PCM_IOCTL_DELAY:
3337 		return snd_pcm_delay(substream, frames);
3338 	default:
3339 		return -EINVAL;
3340 	}
3341 }
3342 EXPORT_SYMBOL(snd_pcm_kernel_ioctl);
3343 
3344 static ssize_t snd_pcm_read(struct file *file, char __user *buf, size_t count,
3345 			    loff_t * offset)
3346 {
3347 	struct snd_pcm_file *pcm_file;
3348 	struct snd_pcm_substream *substream;
3349 	struct snd_pcm_runtime *runtime;
3350 	snd_pcm_sframes_t result;
3351 
3352 	pcm_file = file->private_data;
3353 	substream = pcm_file->substream;
3354 	if (PCM_RUNTIME_CHECK(substream))
3355 		return -ENXIO;
3356 	runtime = substream->runtime;
3357 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3358 		return -EBADFD;
3359 	if (!frame_aligned(runtime, count))
3360 		return -EINVAL;
3361 	count = bytes_to_frames(runtime, count);
3362 	result = snd_pcm_lib_read(substream, buf, count);
3363 	if (result > 0)
3364 		result = frames_to_bytes(runtime, result);
3365 	return result;
3366 }
3367 
3368 static ssize_t snd_pcm_write(struct file *file, const char __user *buf,
3369 			     size_t count, loff_t * offset)
3370 {
3371 	struct snd_pcm_file *pcm_file;
3372 	struct snd_pcm_substream *substream;
3373 	struct snd_pcm_runtime *runtime;
3374 	snd_pcm_sframes_t result;
3375 
3376 	pcm_file = file->private_data;
3377 	substream = pcm_file->substream;
3378 	if (PCM_RUNTIME_CHECK(substream))
3379 		return -ENXIO;
3380 	runtime = substream->runtime;
3381 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3382 		return -EBADFD;
3383 	if (!frame_aligned(runtime, count))
3384 		return -EINVAL;
3385 	count = bytes_to_frames(runtime, count);
3386 	result = snd_pcm_lib_write(substream, buf, count);
3387 	if (result > 0)
3388 		result = frames_to_bytes(runtime, result);
3389 	return result;
3390 }
3391 
3392 static ssize_t snd_pcm_readv(struct kiocb *iocb, struct iov_iter *to)
3393 {
3394 	struct snd_pcm_file *pcm_file;
3395 	struct snd_pcm_substream *substream;
3396 	struct snd_pcm_runtime *runtime;
3397 	snd_pcm_sframes_t result;
3398 	unsigned long i;
3399 	void __user **bufs;
3400 	snd_pcm_uframes_t frames;
3401 
3402 	pcm_file = iocb->ki_filp->private_data;
3403 	substream = pcm_file->substream;
3404 	if (PCM_RUNTIME_CHECK(substream))
3405 		return -ENXIO;
3406 	runtime = substream->runtime;
3407 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3408 		return -EBADFD;
3409 	if (!iter_is_iovec(to))
3410 		return -EINVAL;
3411 	if (to->nr_segs > 1024 || to->nr_segs != runtime->channels)
3412 		return -EINVAL;
3413 	if (!frame_aligned(runtime, to->iov->iov_len))
3414 		return -EINVAL;
3415 	frames = bytes_to_samples(runtime, to->iov->iov_len);
3416 	bufs = kmalloc_array(to->nr_segs, sizeof(void *), GFP_KERNEL);
3417 	if (bufs == NULL)
3418 		return -ENOMEM;
3419 	for (i = 0; i < to->nr_segs; ++i)
3420 		bufs[i] = to->iov[i].iov_base;
3421 	result = snd_pcm_lib_readv(substream, bufs, frames);
3422 	if (result > 0)
3423 		result = frames_to_bytes(runtime, result);
3424 	kfree(bufs);
3425 	return result;
3426 }
3427 
3428 static ssize_t snd_pcm_writev(struct kiocb *iocb, struct iov_iter *from)
3429 {
3430 	struct snd_pcm_file *pcm_file;
3431 	struct snd_pcm_substream *substream;
3432 	struct snd_pcm_runtime *runtime;
3433 	snd_pcm_sframes_t result;
3434 	unsigned long i;
3435 	void __user **bufs;
3436 	snd_pcm_uframes_t frames;
3437 
3438 	pcm_file = iocb->ki_filp->private_data;
3439 	substream = pcm_file->substream;
3440 	if (PCM_RUNTIME_CHECK(substream))
3441 		return -ENXIO;
3442 	runtime = substream->runtime;
3443 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3444 		return -EBADFD;
3445 	if (!iter_is_iovec(from))
3446 		return -EINVAL;
3447 	if (from->nr_segs > 128 || from->nr_segs != runtime->channels ||
3448 	    !frame_aligned(runtime, from->iov->iov_len))
3449 		return -EINVAL;
3450 	frames = bytes_to_samples(runtime, from->iov->iov_len);
3451 	bufs = kmalloc_array(from->nr_segs, sizeof(void *), GFP_KERNEL);
3452 	if (bufs == NULL)
3453 		return -ENOMEM;
3454 	for (i = 0; i < from->nr_segs; ++i)
3455 		bufs[i] = from->iov[i].iov_base;
3456 	result = snd_pcm_lib_writev(substream, bufs, frames);
3457 	if (result > 0)
3458 		result = frames_to_bytes(runtime, result);
3459 	kfree(bufs);
3460 	return result;
3461 }
3462 
3463 static __poll_t snd_pcm_poll(struct file *file, poll_table *wait)
3464 {
3465 	struct snd_pcm_file *pcm_file;
3466 	struct snd_pcm_substream *substream;
3467 	struct snd_pcm_runtime *runtime;
3468 	__poll_t mask, ok;
3469 	snd_pcm_uframes_t avail;
3470 
3471 	pcm_file = file->private_data;
3472 
3473 	substream = pcm_file->substream;
3474 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
3475 		ok = EPOLLOUT | EPOLLWRNORM;
3476 	else
3477 		ok = EPOLLIN | EPOLLRDNORM;
3478 	if (PCM_RUNTIME_CHECK(substream))
3479 		return ok | EPOLLERR;
3480 
3481 	runtime = substream->runtime;
3482 	poll_wait(file, &runtime->sleep, wait);
3483 
3484 	mask = 0;
3485 	snd_pcm_stream_lock_irq(substream);
3486 	avail = snd_pcm_avail(substream);
3487 	switch (runtime->status->state) {
3488 	case SNDRV_PCM_STATE_RUNNING:
3489 	case SNDRV_PCM_STATE_PREPARED:
3490 	case SNDRV_PCM_STATE_PAUSED:
3491 		if (avail >= runtime->control->avail_min)
3492 			mask = ok;
3493 		break;
3494 	case SNDRV_PCM_STATE_DRAINING:
3495 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
3496 			mask = ok;
3497 			if (!avail)
3498 				mask |= EPOLLERR;
3499 		}
3500 		break;
3501 	default:
3502 		mask = ok | EPOLLERR;
3503 		break;
3504 	}
3505 	snd_pcm_stream_unlock_irq(substream);
3506 	return mask;
3507 }
3508 
3509 /*
3510  * mmap support
3511  */
3512 
3513 /*
3514  * Only on coherent architectures, we can mmap the status and the control records
3515  * for effcient data transfer.  On others, we have to use HWSYNC ioctl...
3516  */
3517 #if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_ALPHA)
3518 /*
3519  * mmap status record
3520  */
3521 static vm_fault_t snd_pcm_mmap_status_fault(struct vm_fault *vmf)
3522 {
3523 	struct snd_pcm_substream *substream = vmf->vma->vm_private_data;
3524 	struct snd_pcm_runtime *runtime;
3525 
3526 	if (substream == NULL)
3527 		return VM_FAULT_SIGBUS;
3528 	runtime = substream->runtime;
3529 	vmf->page = virt_to_page(runtime->status);
3530 	get_page(vmf->page);
3531 	return 0;
3532 }
3533 
3534 static const struct vm_operations_struct snd_pcm_vm_ops_status =
3535 {
3536 	.fault =	snd_pcm_mmap_status_fault,
3537 };
3538 
3539 static int snd_pcm_mmap_status(struct snd_pcm_substream *substream, struct file *file,
3540 			       struct vm_area_struct *area)
3541 {
3542 	long size;
3543 	if (!(area->vm_flags & VM_READ))
3544 		return -EINVAL;
3545 	size = area->vm_end - area->vm_start;
3546 	if (size != PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)))
3547 		return -EINVAL;
3548 	area->vm_ops = &snd_pcm_vm_ops_status;
3549 	area->vm_private_data = substream;
3550 	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
3551 	return 0;
3552 }
3553 
3554 /*
3555  * mmap control record
3556  */
3557 static vm_fault_t snd_pcm_mmap_control_fault(struct vm_fault *vmf)
3558 {
3559 	struct snd_pcm_substream *substream = vmf->vma->vm_private_data;
3560 	struct snd_pcm_runtime *runtime;
3561 
3562 	if (substream == NULL)
3563 		return VM_FAULT_SIGBUS;
3564 	runtime = substream->runtime;
3565 	vmf->page = virt_to_page(runtime->control);
3566 	get_page(vmf->page);
3567 	return 0;
3568 }
3569 
3570 static const struct vm_operations_struct snd_pcm_vm_ops_control =
3571 {
3572 	.fault =	snd_pcm_mmap_control_fault,
3573 };
3574 
3575 static int snd_pcm_mmap_control(struct snd_pcm_substream *substream, struct file *file,
3576 				struct vm_area_struct *area)
3577 {
3578 	long size;
3579 	if (!(area->vm_flags & VM_READ))
3580 		return -EINVAL;
3581 	size = area->vm_end - area->vm_start;
3582 	if (size != PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)))
3583 		return -EINVAL;
3584 	area->vm_ops = &snd_pcm_vm_ops_control;
3585 	area->vm_private_data = substream;
3586 	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
3587 	return 0;
3588 }
3589 
3590 static bool pcm_status_mmap_allowed(struct snd_pcm_file *pcm_file)
3591 {
3592 	/* See pcm_control_mmap_allowed() below.
3593 	 * Since older alsa-lib requires both status and control mmaps to be
3594 	 * coupled, we have to disable the status mmap for old alsa-lib, too.
3595 	 */
3596 	if (pcm_file->user_pversion < SNDRV_PROTOCOL_VERSION(2, 0, 14) &&
3597 	    (pcm_file->substream->runtime->hw.info & SNDRV_PCM_INFO_SYNC_APPLPTR))
3598 		return false;
3599 	return true;
3600 }
3601 
3602 static bool pcm_control_mmap_allowed(struct snd_pcm_file *pcm_file)
3603 {
3604 	if (pcm_file->no_compat_mmap)
3605 		return false;
3606 	/* Disallow the control mmap when SYNC_APPLPTR flag is set;
3607 	 * it enforces the user-space to fall back to snd_pcm_sync_ptr(),
3608 	 * thus it effectively assures the manual update of appl_ptr.
3609 	 */
3610 	if (pcm_file->substream->runtime->hw.info & SNDRV_PCM_INFO_SYNC_APPLPTR)
3611 		return false;
3612 	return true;
3613 }
3614 
3615 #else /* ! coherent mmap */
3616 /*
3617  * don't support mmap for status and control records.
3618  */
3619 #define pcm_status_mmap_allowed(pcm_file)	false
3620 #define pcm_control_mmap_allowed(pcm_file)	false
3621 
3622 static int snd_pcm_mmap_status(struct snd_pcm_substream *substream, struct file *file,
3623 			       struct vm_area_struct *area)
3624 {
3625 	return -ENXIO;
3626 }
3627 static int snd_pcm_mmap_control(struct snd_pcm_substream *substream, struct file *file,
3628 				struct vm_area_struct *area)
3629 {
3630 	return -ENXIO;
3631 }
3632 #endif /* coherent mmap */
3633 
3634 static inline struct page *
3635 snd_pcm_default_page_ops(struct snd_pcm_substream *substream, unsigned long ofs)
3636 {
3637 	void *vaddr = substream->runtime->dma_area + ofs;
3638 
3639 	switch (substream->dma_buffer.dev.type) {
3640 #ifdef CONFIG_SND_DMA_SGBUF
3641 	case SNDRV_DMA_TYPE_DEV_SG:
3642 	case SNDRV_DMA_TYPE_DEV_UC_SG:
3643 		return snd_pcm_sgbuf_ops_page(substream, ofs);
3644 #endif /* CONFIG_SND_DMA_SGBUF */
3645 	case SNDRV_DMA_TYPE_VMALLOC:
3646 		return vmalloc_to_page(vaddr);
3647 	default:
3648 		return virt_to_page(vaddr);
3649 	}
3650 }
3651 
3652 /*
3653  * fault callback for mmapping a RAM page
3654  */
3655 static vm_fault_t snd_pcm_mmap_data_fault(struct vm_fault *vmf)
3656 {
3657 	struct snd_pcm_substream *substream = vmf->vma->vm_private_data;
3658 	struct snd_pcm_runtime *runtime;
3659 	unsigned long offset;
3660 	struct page * page;
3661 	size_t dma_bytes;
3662 
3663 	if (substream == NULL)
3664 		return VM_FAULT_SIGBUS;
3665 	runtime = substream->runtime;
3666 	offset = vmf->pgoff << PAGE_SHIFT;
3667 	dma_bytes = PAGE_ALIGN(runtime->dma_bytes);
3668 	if (offset > dma_bytes - PAGE_SIZE)
3669 		return VM_FAULT_SIGBUS;
3670 	if (substream->ops->page)
3671 		page = substream->ops->page(substream, offset);
3672 	else
3673 		page = snd_pcm_default_page_ops(substream, offset);
3674 	if (!page)
3675 		return VM_FAULT_SIGBUS;
3676 	get_page(page);
3677 	vmf->page = page;
3678 	return 0;
3679 }
3680 
3681 static const struct vm_operations_struct snd_pcm_vm_ops_data = {
3682 	.open =		snd_pcm_mmap_data_open,
3683 	.close =	snd_pcm_mmap_data_close,
3684 };
3685 
3686 static const struct vm_operations_struct snd_pcm_vm_ops_data_fault = {
3687 	.open =		snd_pcm_mmap_data_open,
3688 	.close =	snd_pcm_mmap_data_close,
3689 	.fault =	snd_pcm_mmap_data_fault,
3690 };
3691 
3692 /*
3693  * mmap the DMA buffer on RAM
3694  */
3695 
3696 /**
3697  * snd_pcm_lib_default_mmap - Default PCM data mmap function
3698  * @substream: PCM substream
3699  * @area: VMA
3700  *
3701  * This is the default mmap handler for PCM data.  When mmap pcm_ops is NULL,
3702  * this function is invoked implicitly.
3703  */
3704 int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
3705 			     struct vm_area_struct *area)
3706 {
3707 	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
3708 #ifdef CONFIG_GENERIC_ALLOCATOR
3709 	if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV_IRAM) {
3710 		area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
3711 		return remap_pfn_range(area, area->vm_start,
3712 				substream->dma_buffer.addr >> PAGE_SHIFT,
3713 				area->vm_end - area->vm_start, area->vm_page_prot);
3714 	}
3715 #endif /* CONFIG_GENERIC_ALLOCATOR */
3716 	if (IS_ENABLED(CONFIG_HAS_DMA) && !substream->ops->page &&
3717 	    (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV ||
3718 	     substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV_UC))
3719 		return dma_mmap_coherent(substream->dma_buffer.dev.dev,
3720 					 area,
3721 					 substream->runtime->dma_area,
3722 					 substream->runtime->dma_addr,
3723 					 substream->runtime->dma_bytes);
3724 	/* mmap with fault handler */
3725 	area->vm_ops = &snd_pcm_vm_ops_data_fault;
3726 	return 0;
3727 }
3728 EXPORT_SYMBOL_GPL(snd_pcm_lib_default_mmap);
3729 
3730 /*
3731  * mmap the DMA buffer on I/O memory area
3732  */
3733 #if SNDRV_PCM_INFO_MMAP_IOMEM
3734 /**
3735  * snd_pcm_lib_mmap_iomem - Default PCM data mmap function for I/O mem
3736  * @substream: PCM substream
3737  * @area: VMA
3738  *
3739  * When your hardware uses the iomapped pages as the hardware buffer and
3740  * wants to mmap it, pass this function as mmap pcm_ops.  Note that this
3741  * is supposed to work only on limited architectures.
3742  */
3743 int snd_pcm_lib_mmap_iomem(struct snd_pcm_substream *substream,
3744 			   struct vm_area_struct *area)
3745 {
3746 	struct snd_pcm_runtime *runtime = substream->runtime;
3747 
3748 	area->vm_page_prot = pgprot_noncached(area->vm_page_prot);
3749 	return vm_iomap_memory(area, runtime->dma_addr, runtime->dma_bytes);
3750 }
3751 EXPORT_SYMBOL(snd_pcm_lib_mmap_iomem);
3752 #endif /* SNDRV_PCM_INFO_MMAP */
3753 
3754 /*
3755  * mmap DMA buffer
3756  */
3757 int snd_pcm_mmap_data(struct snd_pcm_substream *substream, struct file *file,
3758 		      struct vm_area_struct *area)
3759 {
3760 	struct snd_pcm_runtime *runtime;
3761 	long size;
3762 	unsigned long offset;
3763 	size_t dma_bytes;
3764 	int err;
3765 
3766 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
3767 		if (!(area->vm_flags & (VM_WRITE|VM_READ)))
3768 			return -EINVAL;
3769 	} else {
3770 		if (!(area->vm_flags & VM_READ))
3771 			return -EINVAL;
3772 	}
3773 	runtime = substream->runtime;
3774 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3775 		return -EBADFD;
3776 	if (!(runtime->info & SNDRV_PCM_INFO_MMAP))
3777 		return -ENXIO;
3778 	if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
3779 	    runtime->access == SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
3780 		return -EINVAL;
3781 	size = area->vm_end - area->vm_start;
3782 	offset = area->vm_pgoff << PAGE_SHIFT;
3783 	dma_bytes = PAGE_ALIGN(runtime->dma_bytes);
3784 	if ((size_t)size > dma_bytes)
3785 		return -EINVAL;
3786 	if (offset > dma_bytes - size)
3787 		return -EINVAL;
3788 
3789 	area->vm_ops = &snd_pcm_vm_ops_data;
3790 	area->vm_private_data = substream;
3791 	if (substream->ops->mmap)
3792 		err = substream->ops->mmap(substream, area);
3793 	else
3794 		err = snd_pcm_lib_default_mmap(substream, area);
3795 	if (!err)
3796 		atomic_inc(&substream->mmap_count);
3797 	return err;
3798 }
3799 EXPORT_SYMBOL(snd_pcm_mmap_data);
3800 
3801 static int snd_pcm_mmap(struct file *file, struct vm_area_struct *area)
3802 {
3803 	struct snd_pcm_file * pcm_file;
3804 	struct snd_pcm_substream *substream;
3805 	unsigned long offset;
3806 
3807 	pcm_file = file->private_data;
3808 	substream = pcm_file->substream;
3809 	if (PCM_RUNTIME_CHECK(substream))
3810 		return -ENXIO;
3811 
3812 	offset = area->vm_pgoff << PAGE_SHIFT;
3813 	switch (offset) {
3814 	case SNDRV_PCM_MMAP_OFFSET_STATUS_OLD:
3815 		if (pcm_file->no_compat_mmap || !IS_ENABLED(CONFIG_64BIT))
3816 			return -ENXIO;
3817 		fallthrough;
3818 	case SNDRV_PCM_MMAP_OFFSET_STATUS_NEW:
3819 		if (!pcm_status_mmap_allowed(pcm_file))
3820 			return -ENXIO;
3821 		return snd_pcm_mmap_status(substream, file, area);
3822 	case SNDRV_PCM_MMAP_OFFSET_CONTROL_OLD:
3823 		if (pcm_file->no_compat_mmap || !IS_ENABLED(CONFIG_64BIT))
3824 			return -ENXIO;
3825 		fallthrough;
3826 	case SNDRV_PCM_MMAP_OFFSET_CONTROL_NEW:
3827 		if (!pcm_control_mmap_allowed(pcm_file))
3828 			return -ENXIO;
3829 		return snd_pcm_mmap_control(substream, file, area);
3830 	default:
3831 		return snd_pcm_mmap_data(substream, file, area);
3832 	}
3833 	return 0;
3834 }
3835 
3836 static int snd_pcm_fasync(int fd, struct file * file, int on)
3837 {
3838 	struct snd_pcm_file * pcm_file;
3839 	struct snd_pcm_substream *substream;
3840 	struct snd_pcm_runtime *runtime;
3841 
3842 	pcm_file = file->private_data;
3843 	substream = pcm_file->substream;
3844 	if (PCM_RUNTIME_CHECK(substream))
3845 		return -ENXIO;
3846 	runtime = substream->runtime;
3847 	return fasync_helper(fd, file, on, &runtime->fasync);
3848 }
3849 
3850 /*
3851  * ioctl32 compat
3852  */
3853 #ifdef CONFIG_COMPAT
3854 #include "pcm_compat.c"
3855 #else
3856 #define snd_pcm_ioctl_compat	NULL
3857 #endif
3858 
3859 /*
3860  *  To be removed helpers to keep binary compatibility
3861  */
3862 
3863 #ifdef CONFIG_SND_SUPPORT_OLD_API
3864 #define __OLD_TO_NEW_MASK(x) ((x&7)|((x&0x07fffff8)<<5))
3865 #define __NEW_TO_OLD_MASK(x) ((x&7)|((x&0xffffff00)>>5))
3866 
3867 static void snd_pcm_hw_convert_from_old_params(struct snd_pcm_hw_params *params,
3868 					       struct snd_pcm_hw_params_old *oparams)
3869 {
3870 	unsigned int i;
3871 
3872 	memset(params, 0, sizeof(*params));
3873 	params->flags = oparams->flags;
3874 	for (i = 0; i < ARRAY_SIZE(oparams->masks); i++)
3875 		params->masks[i].bits[0] = oparams->masks[i];
3876 	memcpy(params->intervals, oparams->intervals, sizeof(oparams->intervals));
3877 	params->rmask = __OLD_TO_NEW_MASK(oparams->rmask);
3878 	params->cmask = __OLD_TO_NEW_MASK(oparams->cmask);
3879 	params->info = oparams->info;
3880 	params->msbits = oparams->msbits;
3881 	params->rate_num = oparams->rate_num;
3882 	params->rate_den = oparams->rate_den;
3883 	params->fifo_size = oparams->fifo_size;
3884 }
3885 
3886 static void snd_pcm_hw_convert_to_old_params(struct snd_pcm_hw_params_old *oparams,
3887 					     struct snd_pcm_hw_params *params)
3888 {
3889 	unsigned int i;
3890 
3891 	memset(oparams, 0, sizeof(*oparams));
3892 	oparams->flags = params->flags;
3893 	for (i = 0; i < ARRAY_SIZE(oparams->masks); i++)
3894 		oparams->masks[i] = params->masks[i].bits[0];
3895 	memcpy(oparams->intervals, params->intervals, sizeof(oparams->intervals));
3896 	oparams->rmask = __NEW_TO_OLD_MASK(params->rmask);
3897 	oparams->cmask = __NEW_TO_OLD_MASK(params->cmask);
3898 	oparams->info = params->info;
3899 	oparams->msbits = params->msbits;
3900 	oparams->rate_num = params->rate_num;
3901 	oparams->rate_den = params->rate_den;
3902 	oparams->fifo_size = params->fifo_size;
3903 }
3904 
3905 static int snd_pcm_hw_refine_old_user(struct snd_pcm_substream *substream,
3906 				      struct snd_pcm_hw_params_old __user * _oparams)
3907 {
3908 	struct snd_pcm_hw_params *params;
3909 	struct snd_pcm_hw_params_old *oparams = NULL;
3910 	int err;
3911 
3912 	params = kmalloc(sizeof(*params), GFP_KERNEL);
3913 	if (!params)
3914 		return -ENOMEM;
3915 
3916 	oparams = memdup_user(_oparams, sizeof(*oparams));
3917 	if (IS_ERR(oparams)) {
3918 		err = PTR_ERR(oparams);
3919 		goto out;
3920 	}
3921 	snd_pcm_hw_convert_from_old_params(params, oparams);
3922 	err = snd_pcm_hw_refine(substream, params);
3923 	if (err < 0)
3924 		goto out_old;
3925 
3926 	err = fixup_unreferenced_params(substream, params);
3927 	if (err < 0)
3928 		goto out_old;
3929 
3930 	snd_pcm_hw_convert_to_old_params(oparams, params);
3931 	if (copy_to_user(_oparams, oparams, sizeof(*oparams)))
3932 		err = -EFAULT;
3933 out_old:
3934 	kfree(oparams);
3935 out:
3936 	kfree(params);
3937 	return err;
3938 }
3939 
3940 static int snd_pcm_hw_params_old_user(struct snd_pcm_substream *substream,
3941 				      struct snd_pcm_hw_params_old __user * _oparams)
3942 {
3943 	struct snd_pcm_hw_params *params;
3944 	struct snd_pcm_hw_params_old *oparams = NULL;
3945 	int err;
3946 
3947 	params = kmalloc(sizeof(*params), GFP_KERNEL);
3948 	if (!params)
3949 		return -ENOMEM;
3950 
3951 	oparams = memdup_user(_oparams, sizeof(*oparams));
3952 	if (IS_ERR(oparams)) {
3953 		err = PTR_ERR(oparams);
3954 		goto out;
3955 	}
3956 
3957 	snd_pcm_hw_convert_from_old_params(params, oparams);
3958 	err = snd_pcm_hw_params(substream, params);
3959 	if (err < 0)
3960 		goto out_old;
3961 
3962 	snd_pcm_hw_convert_to_old_params(oparams, params);
3963 	if (copy_to_user(_oparams, oparams, sizeof(*oparams)))
3964 		err = -EFAULT;
3965 out_old:
3966 	kfree(oparams);
3967 out:
3968 	kfree(params);
3969 	return err;
3970 }
3971 #endif /* CONFIG_SND_SUPPORT_OLD_API */
3972 
3973 #ifndef CONFIG_MMU
3974 static unsigned long snd_pcm_get_unmapped_area(struct file *file,
3975 					       unsigned long addr,
3976 					       unsigned long len,
3977 					       unsigned long pgoff,
3978 					       unsigned long flags)
3979 {
3980 	struct snd_pcm_file *pcm_file = file->private_data;
3981 	struct snd_pcm_substream *substream = pcm_file->substream;
3982 	struct snd_pcm_runtime *runtime = substream->runtime;
3983 	unsigned long offset = pgoff << PAGE_SHIFT;
3984 
3985 	switch (offset) {
3986 	case SNDRV_PCM_MMAP_OFFSET_STATUS_NEW:
3987 		return (unsigned long)runtime->status;
3988 	case SNDRV_PCM_MMAP_OFFSET_CONTROL_NEW:
3989 		return (unsigned long)runtime->control;
3990 	default:
3991 		return (unsigned long)runtime->dma_area + offset;
3992 	}
3993 }
3994 #else
3995 # define snd_pcm_get_unmapped_area NULL
3996 #endif
3997 
3998 /*
3999  *  Register section
4000  */
4001 
4002 const struct file_operations snd_pcm_f_ops[2] = {
4003 	{
4004 		.owner =		THIS_MODULE,
4005 		.write =		snd_pcm_write,
4006 		.write_iter =		snd_pcm_writev,
4007 		.open =			snd_pcm_playback_open,
4008 		.release =		snd_pcm_release,
4009 		.llseek =		no_llseek,
4010 		.poll =			snd_pcm_poll,
4011 		.unlocked_ioctl =	snd_pcm_ioctl,
4012 		.compat_ioctl = 	snd_pcm_ioctl_compat,
4013 		.mmap =			snd_pcm_mmap,
4014 		.fasync =		snd_pcm_fasync,
4015 		.get_unmapped_area =	snd_pcm_get_unmapped_area,
4016 	},
4017 	{
4018 		.owner =		THIS_MODULE,
4019 		.read =			snd_pcm_read,
4020 		.read_iter =		snd_pcm_readv,
4021 		.open =			snd_pcm_capture_open,
4022 		.release =		snd_pcm_release,
4023 		.llseek =		no_llseek,
4024 		.poll =			snd_pcm_poll,
4025 		.unlocked_ioctl =	snd_pcm_ioctl,
4026 		.compat_ioctl = 	snd_pcm_ioctl_compat,
4027 		.mmap =			snd_pcm_mmap,
4028 		.fasync =		snd_pcm_fasync,
4029 		.get_unmapped_area =	snd_pcm_get_unmapped_area,
4030 	}
4031 };
4032