xref: /openbmc/linux/sound/core/pcm_native.c (revision 66a28915)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Digital Audio (PCM) abstract layer
4  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5  */
6 
7 #include <linux/compat.h>
8 #include <linux/mm.h>
9 #include <linux/module.h>
10 #include <linux/file.h>
11 #include <linux/slab.h>
12 #include <linux/sched/signal.h>
13 #include <linux/time.h>
14 #include <linux/pm_qos.h>
15 #include <linux/io.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/vmalloc.h>
18 #include <sound/core.h>
19 #include <sound/control.h>
20 #include <sound/info.h>
21 #include <sound/pcm.h>
22 #include <sound/pcm_params.h>
23 #include <sound/timer.h>
24 #include <sound/minors.h>
25 #include <linux/uio.h>
26 #include <linux/delay.h>
27 
28 #include "pcm_local.h"
29 
30 #ifdef CONFIG_SND_DEBUG
31 #define CREATE_TRACE_POINTS
32 #include "pcm_param_trace.h"
33 #else
34 #define trace_hw_mask_param_enabled()		0
35 #define trace_hw_interval_param_enabled()	0
36 #define trace_hw_mask_param(substream, type, index, prev, curr)
37 #define trace_hw_interval_param(substream, type, index, prev, curr)
38 #endif
39 
40 /*
41  *  Compatibility
42  */
43 
44 struct snd_pcm_hw_params_old {
45 	unsigned int flags;
46 	unsigned int masks[SNDRV_PCM_HW_PARAM_SUBFORMAT -
47 			   SNDRV_PCM_HW_PARAM_ACCESS + 1];
48 	struct snd_interval intervals[SNDRV_PCM_HW_PARAM_TICK_TIME -
49 					SNDRV_PCM_HW_PARAM_SAMPLE_BITS + 1];
50 	unsigned int rmask;
51 	unsigned int cmask;
52 	unsigned int info;
53 	unsigned int msbits;
54 	unsigned int rate_num;
55 	unsigned int rate_den;
56 	snd_pcm_uframes_t fifo_size;
57 	unsigned char reserved[64];
58 };
59 
60 #ifdef CONFIG_SND_SUPPORT_OLD_API
61 #define SNDRV_PCM_IOCTL_HW_REFINE_OLD _IOWR('A', 0x10, struct snd_pcm_hw_params_old)
62 #define SNDRV_PCM_IOCTL_HW_PARAMS_OLD _IOWR('A', 0x11, struct snd_pcm_hw_params_old)
63 
64 static int snd_pcm_hw_refine_old_user(struct snd_pcm_substream *substream,
65 				      struct snd_pcm_hw_params_old __user * _oparams);
66 static int snd_pcm_hw_params_old_user(struct snd_pcm_substream *substream,
67 				      struct snd_pcm_hw_params_old __user * _oparams);
68 #endif
69 static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream);
70 
71 /*
72  *
73  */
74 
75 static DECLARE_RWSEM(snd_pcm_link_rwsem);
76 
77 void snd_pcm_group_init(struct snd_pcm_group *group)
78 {
79 	spin_lock_init(&group->lock);
80 	mutex_init(&group->mutex);
81 	INIT_LIST_HEAD(&group->substreams);
82 	refcount_set(&group->refs, 1);
83 }
84 
85 /* define group lock helpers */
86 #define DEFINE_PCM_GROUP_LOCK(action, mutex_action) \
87 static void snd_pcm_group_ ## action(struct snd_pcm_group *group, bool nonatomic) \
88 { \
89 	if (nonatomic) \
90 		mutex_ ## mutex_action(&group->mutex); \
91 	else \
92 		spin_ ## action(&group->lock); \
93 }
94 
95 DEFINE_PCM_GROUP_LOCK(lock, lock);
96 DEFINE_PCM_GROUP_LOCK(unlock, unlock);
97 DEFINE_PCM_GROUP_LOCK(lock_irq, lock);
98 DEFINE_PCM_GROUP_LOCK(unlock_irq, unlock);
99 
100 /**
101  * snd_pcm_stream_lock - Lock the PCM stream
102  * @substream: PCM substream
103  *
104  * This locks the PCM stream's spinlock or mutex depending on the nonatomic
105  * flag of the given substream.  This also takes the global link rw lock
106  * (or rw sem), too, for avoiding the race with linked streams.
107  */
108 void snd_pcm_stream_lock(struct snd_pcm_substream *substream)
109 {
110 	snd_pcm_group_lock(&substream->self_group, substream->pcm->nonatomic);
111 }
112 EXPORT_SYMBOL_GPL(snd_pcm_stream_lock);
113 
114 /**
115  * snd_pcm_stream_unlock - Unlock the PCM stream
116  * @substream: PCM substream
117  *
118  * This unlocks the PCM stream that has been locked via snd_pcm_stream_lock().
119  */
120 void snd_pcm_stream_unlock(struct snd_pcm_substream *substream)
121 {
122 	snd_pcm_group_unlock(&substream->self_group, substream->pcm->nonatomic);
123 }
124 EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock);
125 
126 /**
127  * snd_pcm_stream_lock_irq - Lock the PCM stream
128  * @substream: PCM substream
129  *
130  * This locks the PCM stream like snd_pcm_stream_lock() and disables the local
131  * IRQ (only when nonatomic is false).  In nonatomic case, this is identical
132  * as snd_pcm_stream_lock().
133  */
134 void snd_pcm_stream_lock_irq(struct snd_pcm_substream *substream)
135 {
136 	snd_pcm_group_lock_irq(&substream->self_group,
137 			       substream->pcm->nonatomic);
138 }
139 EXPORT_SYMBOL_GPL(snd_pcm_stream_lock_irq);
140 
141 static void snd_pcm_stream_lock_nested(struct snd_pcm_substream *substream)
142 {
143 	struct snd_pcm_group *group = &substream->self_group;
144 
145 	if (substream->pcm->nonatomic)
146 		mutex_lock_nested(&group->mutex, SINGLE_DEPTH_NESTING);
147 	else
148 		spin_lock_nested(&group->lock, SINGLE_DEPTH_NESTING);
149 }
150 
151 /**
152  * snd_pcm_stream_unlock_irq - Unlock the PCM stream
153  * @substream: PCM substream
154  *
155  * This is a counter-part of snd_pcm_stream_lock_irq().
156  */
157 void snd_pcm_stream_unlock_irq(struct snd_pcm_substream *substream)
158 {
159 	snd_pcm_group_unlock_irq(&substream->self_group,
160 				 substream->pcm->nonatomic);
161 }
162 EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irq);
163 
164 unsigned long _snd_pcm_stream_lock_irqsave(struct snd_pcm_substream *substream)
165 {
166 	unsigned long flags = 0;
167 	if (substream->pcm->nonatomic)
168 		mutex_lock(&substream->self_group.mutex);
169 	else
170 		spin_lock_irqsave(&substream->self_group.lock, flags);
171 	return flags;
172 }
173 EXPORT_SYMBOL_GPL(_snd_pcm_stream_lock_irqsave);
174 
175 /**
176  * snd_pcm_stream_unlock_irqrestore - Unlock the PCM stream
177  * @substream: PCM substream
178  * @flags: irq flags
179  *
180  * This is a counter-part of snd_pcm_stream_lock_irqsave().
181  */
182 void snd_pcm_stream_unlock_irqrestore(struct snd_pcm_substream *substream,
183 				      unsigned long flags)
184 {
185 	if (substream->pcm->nonatomic)
186 		mutex_unlock(&substream->self_group.mutex);
187 	else
188 		spin_unlock_irqrestore(&substream->self_group.lock, flags);
189 }
190 EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irqrestore);
191 
192 /* Run PCM ioctl ops */
193 static int snd_pcm_ops_ioctl(struct snd_pcm_substream *substream,
194 			     unsigned cmd, void *arg)
195 {
196 	if (substream->ops->ioctl)
197 		return substream->ops->ioctl(substream, cmd, arg);
198 	else
199 		return snd_pcm_lib_ioctl(substream, cmd, arg);
200 }
201 
202 int snd_pcm_info(struct snd_pcm_substream *substream, struct snd_pcm_info *info)
203 {
204 	struct snd_pcm *pcm = substream->pcm;
205 	struct snd_pcm_str *pstr = substream->pstr;
206 
207 	memset(info, 0, sizeof(*info));
208 	info->card = pcm->card->number;
209 	info->device = pcm->device;
210 	info->stream = substream->stream;
211 	info->subdevice = substream->number;
212 	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_params_choose - choose a configuration defined by @params
599  * @pcm: PCM instance
600  * @params: the hw_params instance
601  *
602  * Choose one configuration from configuration space defined by @params.
603  * The configuration chosen is that obtained fixing in this order:
604  * first access, first format, first subformat, min channels,
605  * min rate, min period time, max buffer size, min tick time
606  *
607  * Return: Zero if successful, or a negative error code on failure.
608  */
609 static int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
610 				    struct snd_pcm_hw_params *params)
611 {
612 	static const int vars[] = {
613 		SNDRV_PCM_HW_PARAM_ACCESS,
614 		SNDRV_PCM_HW_PARAM_FORMAT,
615 		SNDRV_PCM_HW_PARAM_SUBFORMAT,
616 		SNDRV_PCM_HW_PARAM_CHANNELS,
617 		SNDRV_PCM_HW_PARAM_RATE,
618 		SNDRV_PCM_HW_PARAM_PERIOD_TIME,
619 		SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
620 		SNDRV_PCM_HW_PARAM_TICK_TIME,
621 		-1
622 	};
623 	const int *v;
624 	struct snd_mask old_mask;
625 	struct snd_interval old_interval;
626 	int changed;
627 
628 	for (v = vars; *v != -1; v++) {
629 		/* Keep old parameter to trace. */
630 		if (trace_hw_mask_param_enabled()) {
631 			if (hw_is_mask(*v))
632 				old_mask = *hw_param_mask(params, *v);
633 		}
634 		if (trace_hw_interval_param_enabled()) {
635 			if (hw_is_interval(*v))
636 				old_interval = *hw_param_interval(params, *v);
637 		}
638 		if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
639 			changed = snd_pcm_hw_param_first(pcm, params, *v, NULL);
640 		else
641 			changed = snd_pcm_hw_param_last(pcm, params, *v, NULL);
642 		if (changed < 0)
643 			return changed;
644 		if (changed == 0)
645 			continue;
646 
647 		/* Trace the changed parameter. */
648 		if (hw_is_mask(*v)) {
649 			trace_hw_mask_param(pcm, *v, 0, &old_mask,
650 					    hw_param_mask(params, *v));
651 		}
652 		if (hw_is_interval(*v)) {
653 			trace_hw_interval_param(pcm, *v, 0, &old_interval,
654 						hw_param_interval(params, *v));
655 		}
656 	}
657 
658 	return 0;
659 }
660 
661 static int snd_pcm_hw_params(struct snd_pcm_substream *substream,
662 			     struct snd_pcm_hw_params *params)
663 {
664 	struct snd_pcm_runtime *runtime;
665 	int err, usecs;
666 	unsigned int bits;
667 	snd_pcm_uframes_t frames;
668 
669 	if (PCM_RUNTIME_CHECK(substream))
670 		return -ENXIO;
671 	runtime = substream->runtime;
672 	snd_pcm_stream_lock_irq(substream);
673 	switch (runtime->status->state) {
674 	case SNDRV_PCM_STATE_OPEN:
675 	case SNDRV_PCM_STATE_SETUP:
676 	case SNDRV_PCM_STATE_PREPARED:
677 		break;
678 	default:
679 		snd_pcm_stream_unlock_irq(substream);
680 		return -EBADFD;
681 	}
682 	snd_pcm_stream_unlock_irq(substream);
683 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
684 	if (!substream->oss.oss)
685 #endif
686 		if (atomic_read(&substream->mmap_count))
687 			return -EBADFD;
688 
689 	snd_pcm_sync_stop(substream);
690 
691 	params->rmask = ~0U;
692 	err = snd_pcm_hw_refine(substream, params);
693 	if (err < 0)
694 		goto _error;
695 
696 	err = snd_pcm_hw_params_choose(substream, params);
697 	if (err < 0)
698 		goto _error;
699 
700 	err = fixup_unreferenced_params(substream, params);
701 	if (err < 0)
702 		goto _error;
703 
704 	if (substream->managed_buffer_alloc) {
705 		err = snd_pcm_lib_malloc_pages(substream,
706 					       params_buffer_bytes(params));
707 		if (err < 0)
708 			goto _error;
709 		runtime->buffer_changed = err > 0;
710 	}
711 
712 	if (substream->ops->hw_params != NULL) {
713 		err = substream->ops->hw_params(substream, params);
714 		if (err < 0)
715 			goto _error;
716 	}
717 
718 	runtime->access = params_access(params);
719 	runtime->format = params_format(params);
720 	runtime->subformat = params_subformat(params);
721 	runtime->channels = params_channels(params);
722 	runtime->rate = params_rate(params);
723 	runtime->period_size = params_period_size(params);
724 	runtime->periods = params_periods(params);
725 	runtime->buffer_size = params_buffer_size(params);
726 	runtime->info = params->info;
727 	runtime->rate_num = params->rate_num;
728 	runtime->rate_den = params->rate_den;
729 	runtime->no_period_wakeup =
730 			(params->info & SNDRV_PCM_INFO_NO_PERIOD_WAKEUP) &&
731 			(params->flags & SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP);
732 
733 	bits = snd_pcm_format_physical_width(runtime->format);
734 	runtime->sample_bits = bits;
735 	bits *= runtime->channels;
736 	runtime->frame_bits = bits;
737 	frames = 1;
738 	while (bits % 8 != 0) {
739 		bits *= 2;
740 		frames *= 2;
741 	}
742 	runtime->byte_align = bits / 8;
743 	runtime->min_align = frames;
744 
745 	/* Default sw params */
746 	runtime->tstamp_mode = SNDRV_PCM_TSTAMP_NONE;
747 	runtime->period_step = 1;
748 	runtime->control->avail_min = runtime->period_size;
749 	runtime->start_threshold = 1;
750 	runtime->stop_threshold = runtime->buffer_size;
751 	runtime->silence_threshold = 0;
752 	runtime->silence_size = 0;
753 	runtime->boundary = runtime->buffer_size;
754 	while (runtime->boundary * 2 <= LONG_MAX - runtime->buffer_size)
755 		runtime->boundary *= 2;
756 
757 	/* clear the buffer for avoiding possible kernel info leaks */
758 	if (runtime->dma_area && !substream->ops->copy_user) {
759 		size_t size = runtime->dma_bytes;
760 
761 		if (runtime->info & SNDRV_PCM_INFO_MMAP)
762 			size = PAGE_ALIGN(size);
763 		memset(runtime->dma_area, 0, size);
764 	}
765 
766 	snd_pcm_timer_resolution_change(substream);
767 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_SETUP);
768 
769 	if (cpu_latency_qos_request_active(&substream->latency_pm_qos_req))
770 		cpu_latency_qos_remove_request(&substream->latency_pm_qos_req);
771 	if ((usecs = period_to_usecs(runtime)) >= 0)
772 		cpu_latency_qos_add_request(&substream->latency_pm_qos_req,
773 					    usecs);
774 	return 0;
775  _error:
776 	/* hardware might be unusable from this time,
777 	   so we force application to retry to set
778 	   the correct hardware parameter settings */
779 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_OPEN);
780 	if (substream->ops->hw_free != NULL)
781 		substream->ops->hw_free(substream);
782 	if (substream->managed_buffer_alloc)
783 		snd_pcm_lib_free_pages(substream);
784 	return err;
785 }
786 
787 static int snd_pcm_hw_params_user(struct snd_pcm_substream *substream,
788 				  struct snd_pcm_hw_params __user * _params)
789 {
790 	struct snd_pcm_hw_params *params;
791 	int err;
792 
793 	params = memdup_user(_params, sizeof(*params));
794 	if (IS_ERR(params))
795 		return PTR_ERR(params);
796 
797 	err = snd_pcm_hw_params(substream, params);
798 	if (err < 0)
799 		goto end;
800 
801 	if (copy_to_user(_params, params, sizeof(*params)))
802 		err = -EFAULT;
803 end:
804 	kfree(params);
805 	return err;
806 }
807 
808 static int do_hw_free(struct snd_pcm_substream *substream)
809 {
810 	int result = 0;
811 
812 	snd_pcm_sync_stop(substream);
813 	if (substream->ops->hw_free)
814 		result = substream->ops->hw_free(substream);
815 	if (substream->managed_buffer_alloc)
816 		snd_pcm_lib_free_pages(substream);
817 	return result;
818 }
819 
820 static int snd_pcm_hw_free(struct snd_pcm_substream *substream)
821 {
822 	struct snd_pcm_runtime *runtime;
823 	int result;
824 
825 	if (PCM_RUNTIME_CHECK(substream))
826 		return -ENXIO;
827 	runtime = substream->runtime;
828 	snd_pcm_stream_lock_irq(substream);
829 	switch (runtime->status->state) {
830 	case SNDRV_PCM_STATE_SETUP:
831 	case SNDRV_PCM_STATE_PREPARED:
832 		break;
833 	default:
834 		snd_pcm_stream_unlock_irq(substream);
835 		return -EBADFD;
836 	}
837 	snd_pcm_stream_unlock_irq(substream);
838 	if (atomic_read(&substream->mmap_count))
839 		return -EBADFD;
840 	result = do_hw_free(substream);
841 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_OPEN);
842 	cpu_latency_qos_remove_request(&substream->latency_pm_qos_req);
843 	return result;
844 }
845 
846 static int snd_pcm_sw_params(struct snd_pcm_substream *substream,
847 			     struct snd_pcm_sw_params *params)
848 {
849 	struct snd_pcm_runtime *runtime;
850 	int err;
851 
852 	if (PCM_RUNTIME_CHECK(substream))
853 		return -ENXIO;
854 	runtime = substream->runtime;
855 	snd_pcm_stream_lock_irq(substream);
856 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
857 		snd_pcm_stream_unlock_irq(substream);
858 		return -EBADFD;
859 	}
860 	snd_pcm_stream_unlock_irq(substream);
861 
862 	if (params->tstamp_mode < 0 ||
863 	    params->tstamp_mode > SNDRV_PCM_TSTAMP_LAST)
864 		return -EINVAL;
865 	if (params->proto >= SNDRV_PROTOCOL_VERSION(2, 0, 12) &&
866 	    params->tstamp_type > SNDRV_PCM_TSTAMP_TYPE_LAST)
867 		return -EINVAL;
868 	if (params->avail_min == 0)
869 		return -EINVAL;
870 	if (params->silence_size >= runtime->boundary) {
871 		if (params->silence_threshold != 0)
872 			return -EINVAL;
873 	} else {
874 		if (params->silence_size > params->silence_threshold)
875 			return -EINVAL;
876 		if (params->silence_threshold > runtime->buffer_size)
877 			return -EINVAL;
878 	}
879 	err = 0;
880 	snd_pcm_stream_lock_irq(substream);
881 	runtime->tstamp_mode = params->tstamp_mode;
882 	if (params->proto >= SNDRV_PROTOCOL_VERSION(2, 0, 12))
883 		runtime->tstamp_type = params->tstamp_type;
884 	runtime->period_step = params->period_step;
885 	runtime->control->avail_min = params->avail_min;
886 	runtime->start_threshold = params->start_threshold;
887 	runtime->stop_threshold = params->stop_threshold;
888 	runtime->silence_threshold = params->silence_threshold;
889 	runtime->silence_size = params->silence_size;
890         params->boundary = runtime->boundary;
891 	if (snd_pcm_running(substream)) {
892 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
893 		    runtime->silence_size > 0)
894 			snd_pcm_playback_silence(substream, ULONG_MAX);
895 		err = snd_pcm_update_state(substream, runtime);
896 	}
897 	snd_pcm_stream_unlock_irq(substream);
898 	return err;
899 }
900 
901 static int snd_pcm_sw_params_user(struct snd_pcm_substream *substream,
902 				  struct snd_pcm_sw_params __user * _params)
903 {
904 	struct snd_pcm_sw_params params;
905 	int err;
906 	if (copy_from_user(&params, _params, sizeof(params)))
907 		return -EFAULT;
908 	err = snd_pcm_sw_params(substream, &params);
909 	if (copy_to_user(_params, &params, sizeof(params)))
910 		return -EFAULT;
911 	return err;
912 }
913 
914 static inline snd_pcm_uframes_t
915 snd_pcm_calc_delay(struct snd_pcm_substream *substream)
916 {
917 	snd_pcm_uframes_t delay;
918 
919 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
920 		delay = snd_pcm_playback_hw_avail(substream->runtime);
921 	else
922 		delay = snd_pcm_capture_avail(substream->runtime);
923 	return delay + substream->runtime->delay;
924 }
925 
926 int snd_pcm_status64(struct snd_pcm_substream *substream,
927 		     struct snd_pcm_status64 *status)
928 {
929 	struct snd_pcm_runtime *runtime = substream->runtime;
930 
931 	snd_pcm_stream_lock_irq(substream);
932 
933 	snd_pcm_unpack_audio_tstamp_config(status->audio_tstamp_data,
934 					&runtime->audio_tstamp_config);
935 
936 	/* backwards compatible behavior */
937 	if (runtime->audio_tstamp_config.type_requested ==
938 		SNDRV_PCM_AUDIO_TSTAMP_TYPE_COMPAT) {
939 		if (runtime->hw.info & SNDRV_PCM_INFO_HAS_WALL_CLOCK)
940 			runtime->audio_tstamp_config.type_requested =
941 				SNDRV_PCM_AUDIO_TSTAMP_TYPE_LINK;
942 		else
943 			runtime->audio_tstamp_config.type_requested =
944 				SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT;
945 		runtime->audio_tstamp_report.valid = 0;
946 	} else
947 		runtime->audio_tstamp_report.valid = 1;
948 
949 	status->state = runtime->status->state;
950 	status->suspended_state = runtime->status->suspended_state;
951 	if (status->state == SNDRV_PCM_STATE_OPEN)
952 		goto _end;
953 	status->trigger_tstamp_sec = runtime->trigger_tstamp.tv_sec;
954 	status->trigger_tstamp_nsec = runtime->trigger_tstamp.tv_nsec;
955 	if (snd_pcm_running(substream)) {
956 		snd_pcm_update_hw_ptr(substream);
957 		if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
958 			status->tstamp_sec = runtime->status->tstamp.tv_sec;
959 			status->tstamp_nsec =
960 				runtime->status->tstamp.tv_nsec;
961 			status->driver_tstamp_sec =
962 				runtime->driver_tstamp.tv_sec;
963 			status->driver_tstamp_nsec =
964 				runtime->driver_tstamp.tv_nsec;
965 			status->audio_tstamp_sec =
966 				runtime->status->audio_tstamp.tv_sec;
967 			status->audio_tstamp_nsec =
968 				runtime->status->audio_tstamp.tv_nsec;
969 			if (runtime->audio_tstamp_report.valid == 1)
970 				/* backwards compatibility, no report provided in COMPAT mode */
971 				snd_pcm_pack_audio_tstamp_report(&status->audio_tstamp_data,
972 								&status->audio_tstamp_accuracy,
973 								&runtime->audio_tstamp_report);
974 
975 			goto _tstamp_end;
976 		}
977 	} else {
978 		/* get tstamp only in fallback mode and only if enabled */
979 		if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
980 			struct timespec64 tstamp;
981 
982 			snd_pcm_gettime(runtime, &tstamp);
983 			status->tstamp_sec = tstamp.tv_sec;
984 			status->tstamp_nsec = tstamp.tv_nsec;
985 		}
986 	}
987  _tstamp_end:
988 	status->appl_ptr = runtime->control->appl_ptr;
989 	status->hw_ptr = runtime->status->hw_ptr;
990 	status->avail = snd_pcm_avail(substream);
991 	status->delay = snd_pcm_running(substream) ?
992 		snd_pcm_calc_delay(substream) : 0;
993 	status->avail_max = runtime->avail_max;
994 	status->overrange = runtime->overrange;
995 	runtime->avail_max = 0;
996 	runtime->overrange = 0;
997  _end:
998  	snd_pcm_stream_unlock_irq(substream);
999 	return 0;
1000 }
1001 
1002 static int snd_pcm_status_user64(struct snd_pcm_substream *substream,
1003 				 struct snd_pcm_status64 __user * _status,
1004 				 bool ext)
1005 {
1006 	struct snd_pcm_status64 status;
1007 	int res;
1008 
1009 	memset(&status, 0, sizeof(status));
1010 	/*
1011 	 * with extension, parameters are read/write,
1012 	 * get audio_tstamp_data from user,
1013 	 * ignore rest of status structure
1014 	 */
1015 	if (ext && get_user(status.audio_tstamp_data,
1016 				(u32 __user *)(&_status->audio_tstamp_data)))
1017 		return -EFAULT;
1018 	res = snd_pcm_status64(substream, &status);
1019 	if (res < 0)
1020 		return res;
1021 	if (copy_to_user(_status, &status, sizeof(status)))
1022 		return -EFAULT;
1023 	return 0;
1024 }
1025 
1026 static int snd_pcm_status_user32(struct snd_pcm_substream *substream,
1027 				 struct snd_pcm_status32 __user * _status,
1028 				 bool ext)
1029 {
1030 	struct snd_pcm_status64 status64;
1031 	struct snd_pcm_status32 status32;
1032 	int res;
1033 
1034 	memset(&status64, 0, sizeof(status64));
1035 	memset(&status32, 0, sizeof(status32));
1036 	/*
1037 	 * with extension, parameters are read/write,
1038 	 * get audio_tstamp_data from user,
1039 	 * ignore rest of status structure
1040 	 */
1041 	if (ext && get_user(status64.audio_tstamp_data,
1042 			    (u32 __user *)(&_status->audio_tstamp_data)))
1043 		return -EFAULT;
1044 	res = snd_pcm_status64(substream, &status64);
1045 	if (res < 0)
1046 		return res;
1047 
1048 	status32 = (struct snd_pcm_status32) {
1049 		.state = status64.state,
1050 		.trigger_tstamp_sec = status64.trigger_tstamp_sec,
1051 		.trigger_tstamp_nsec = status64.trigger_tstamp_nsec,
1052 		.tstamp_sec = status64.tstamp_sec,
1053 		.tstamp_nsec = status64.tstamp_nsec,
1054 		.appl_ptr = status64.appl_ptr,
1055 		.hw_ptr = status64.hw_ptr,
1056 		.delay = status64.delay,
1057 		.avail = status64.avail,
1058 		.avail_max = status64.avail_max,
1059 		.overrange = status64.overrange,
1060 		.suspended_state = status64.suspended_state,
1061 		.audio_tstamp_data = status64.audio_tstamp_data,
1062 		.audio_tstamp_sec = status64.audio_tstamp_sec,
1063 		.audio_tstamp_nsec = status64.audio_tstamp_nsec,
1064 		.driver_tstamp_sec = status64.audio_tstamp_sec,
1065 		.driver_tstamp_nsec = status64.audio_tstamp_nsec,
1066 		.audio_tstamp_accuracy = status64.audio_tstamp_accuracy,
1067 	};
1068 
1069 	if (copy_to_user(_status, &status32, sizeof(status32)))
1070 		return -EFAULT;
1071 
1072 	return 0;
1073 }
1074 
1075 static int snd_pcm_channel_info(struct snd_pcm_substream *substream,
1076 				struct snd_pcm_channel_info * info)
1077 {
1078 	struct snd_pcm_runtime *runtime;
1079 	unsigned int channel;
1080 
1081 	channel = info->channel;
1082 	runtime = substream->runtime;
1083 	snd_pcm_stream_lock_irq(substream);
1084 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
1085 		snd_pcm_stream_unlock_irq(substream);
1086 		return -EBADFD;
1087 	}
1088 	snd_pcm_stream_unlock_irq(substream);
1089 	if (channel >= runtime->channels)
1090 		return -EINVAL;
1091 	memset(info, 0, sizeof(*info));
1092 	info->channel = channel;
1093 	return snd_pcm_ops_ioctl(substream, SNDRV_PCM_IOCTL1_CHANNEL_INFO, info);
1094 }
1095 
1096 static int snd_pcm_channel_info_user(struct snd_pcm_substream *substream,
1097 				     struct snd_pcm_channel_info __user * _info)
1098 {
1099 	struct snd_pcm_channel_info info;
1100 	int res;
1101 
1102 	if (copy_from_user(&info, _info, sizeof(info)))
1103 		return -EFAULT;
1104 	res = snd_pcm_channel_info(substream, &info);
1105 	if (res < 0)
1106 		return res;
1107 	if (copy_to_user(_info, &info, sizeof(info)))
1108 		return -EFAULT;
1109 	return 0;
1110 }
1111 
1112 static void snd_pcm_trigger_tstamp(struct snd_pcm_substream *substream)
1113 {
1114 	struct snd_pcm_runtime *runtime = substream->runtime;
1115 	if (runtime->trigger_master == NULL)
1116 		return;
1117 	if (runtime->trigger_master == substream) {
1118 		if (!runtime->trigger_tstamp_latched)
1119 			snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
1120 	} else {
1121 		snd_pcm_trigger_tstamp(runtime->trigger_master);
1122 		runtime->trigger_tstamp = runtime->trigger_master->runtime->trigger_tstamp;
1123 	}
1124 	runtime->trigger_master = NULL;
1125 }
1126 
1127 #define ACTION_ARG_IGNORE	(__force snd_pcm_state_t)0
1128 
1129 struct action_ops {
1130 	int (*pre_action)(struct snd_pcm_substream *substream,
1131 			  snd_pcm_state_t state);
1132 	int (*do_action)(struct snd_pcm_substream *substream,
1133 			 snd_pcm_state_t state);
1134 	void (*undo_action)(struct snd_pcm_substream *substream,
1135 			    snd_pcm_state_t state);
1136 	void (*post_action)(struct snd_pcm_substream *substream,
1137 			    snd_pcm_state_t state);
1138 };
1139 
1140 /*
1141  *  this functions is core for handling of linked stream
1142  *  Note: the stream state might be changed also on failure
1143  *  Note2: call with calling stream lock + link lock
1144  */
1145 static int snd_pcm_action_group(const struct action_ops *ops,
1146 				struct snd_pcm_substream *substream,
1147 				snd_pcm_state_t state,
1148 				bool do_lock)
1149 {
1150 	struct snd_pcm_substream *s = NULL;
1151 	struct snd_pcm_substream *s1;
1152 	int res = 0, depth = 1;
1153 
1154 	snd_pcm_group_for_each_entry(s, substream) {
1155 		if (do_lock && s != substream) {
1156 			if (s->pcm->nonatomic)
1157 				mutex_lock_nested(&s->self_group.mutex, depth);
1158 			else
1159 				spin_lock_nested(&s->self_group.lock, depth);
1160 			depth++;
1161 		}
1162 		res = ops->pre_action(s, state);
1163 		if (res < 0)
1164 			goto _unlock;
1165 	}
1166 	snd_pcm_group_for_each_entry(s, substream) {
1167 		res = ops->do_action(s, state);
1168 		if (res < 0) {
1169 			if (ops->undo_action) {
1170 				snd_pcm_group_for_each_entry(s1, substream) {
1171 					if (s1 == s) /* failed stream */
1172 						break;
1173 					ops->undo_action(s1, state);
1174 				}
1175 			}
1176 			s = NULL; /* unlock all */
1177 			goto _unlock;
1178 		}
1179 	}
1180 	snd_pcm_group_for_each_entry(s, substream) {
1181 		ops->post_action(s, state);
1182 	}
1183  _unlock:
1184 	if (do_lock) {
1185 		/* unlock streams */
1186 		snd_pcm_group_for_each_entry(s1, substream) {
1187 			if (s1 != substream) {
1188 				if (s1->pcm->nonatomic)
1189 					mutex_unlock(&s1->self_group.mutex);
1190 				else
1191 					spin_unlock(&s1->self_group.lock);
1192 			}
1193 			if (s1 == s)	/* end */
1194 				break;
1195 		}
1196 	}
1197 	return res;
1198 }
1199 
1200 /*
1201  *  Note: call with stream lock
1202  */
1203 static int snd_pcm_action_single(const struct action_ops *ops,
1204 				 struct snd_pcm_substream *substream,
1205 				 snd_pcm_state_t state)
1206 {
1207 	int res;
1208 
1209 	res = ops->pre_action(substream, state);
1210 	if (res < 0)
1211 		return res;
1212 	res = ops->do_action(substream, state);
1213 	if (res == 0)
1214 		ops->post_action(substream, state);
1215 	else if (ops->undo_action)
1216 		ops->undo_action(substream, state);
1217 	return res;
1218 }
1219 
1220 static void snd_pcm_group_assign(struct snd_pcm_substream *substream,
1221 				 struct snd_pcm_group *new_group)
1222 {
1223 	substream->group = new_group;
1224 	list_move(&substream->link_list, &new_group->substreams);
1225 }
1226 
1227 /*
1228  * Unref and unlock the group, but keep the stream lock;
1229  * when the group becomes empty and no longer referred, destroy itself
1230  */
1231 static void snd_pcm_group_unref(struct snd_pcm_group *group,
1232 				struct snd_pcm_substream *substream)
1233 {
1234 	bool do_free;
1235 
1236 	if (!group)
1237 		return;
1238 	do_free = refcount_dec_and_test(&group->refs);
1239 	snd_pcm_group_unlock(group, substream->pcm->nonatomic);
1240 	if (do_free)
1241 		kfree(group);
1242 }
1243 
1244 /*
1245  * Lock the group inside a stream lock and reference it;
1246  * return the locked group object, or NULL if not linked
1247  */
1248 static struct snd_pcm_group *
1249 snd_pcm_stream_group_ref(struct snd_pcm_substream *substream)
1250 {
1251 	bool nonatomic = substream->pcm->nonatomic;
1252 	struct snd_pcm_group *group;
1253 	bool trylock;
1254 
1255 	for (;;) {
1256 		if (!snd_pcm_stream_linked(substream))
1257 			return NULL;
1258 		group = substream->group;
1259 		/* block freeing the group object */
1260 		refcount_inc(&group->refs);
1261 
1262 		trylock = nonatomic ? mutex_trylock(&group->mutex) :
1263 			spin_trylock(&group->lock);
1264 		if (trylock)
1265 			break; /* OK */
1266 
1267 		/* re-lock for avoiding ABBA deadlock */
1268 		snd_pcm_stream_unlock(substream);
1269 		snd_pcm_group_lock(group, nonatomic);
1270 		snd_pcm_stream_lock(substream);
1271 
1272 		/* check the group again; the above opens a small race window */
1273 		if (substream->group == group)
1274 			break; /* OK */
1275 		/* group changed, try again */
1276 		snd_pcm_group_unref(group, substream);
1277 	}
1278 	return group;
1279 }
1280 
1281 /*
1282  *  Note: call with stream lock
1283  */
1284 static int snd_pcm_action(const struct action_ops *ops,
1285 			  struct snd_pcm_substream *substream,
1286 			  snd_pcm_state_t state)
1287 {
1288 	struct snd_pcm_group *group;
1289 	int res;
1290 
1291 	group = snd_pcm_stream_group_ref(substream);
1292 	if (group)
1293 		res = snd_pcm_action_group(ops, substream, state, true);
1294 	else
1295 		res = snd_pcm_action_single(ops, substream, state);
1296 	snd_pcm_group_unref(group, substream);
1297 	return res;
1298 }
1299 
1300 /*
1301  *  Note: don't use any locks before
1302  */
1303 static int snd_pcm_action_lock_irq(const struct action_ops *ops,
1304 				   struct snd_pcm_substream *substream,
1305 				   snd_pcm_state_t state)
1306 {
1307 	int res;
1308 
1309 	snd_pcm_stream_lock_irq(substream);
1310 	res = snd_pcm_action(ops, substream, state);
1311 	snd_pcm_stream_unlock_irq(substream);
1312 	return res;
1313 }
1314 
1315 /*
1316  */
1317 static int snd_pcm_action_nonatomic(const struct action_ops *ops,
1318 				    struct snd_pcm_substream *substream,
1319 				    snd_pcm_state_t state)
1320 {
1321 	int res;
1322 
1323 	/* Guarantee the group members won't change during non-atomic action */
1324 	down_read(&snd_pcm_link_rwsem);
1325 	if (snd_pcm_stream_linked(substream))
1326 		res = snd_pcm_action_group(ops, substream, state, false);
1327 	else
1328 		res = snd_pcm_action_single(ops, substream, state);
1329 	up_read(&snd_pcm_link_rwsem);
1330 	return res;
1331 }
1332 
1333 /*
1334  * start callbacks
1335  */
1336 static int snd_pcm_pre_start(struct snd_pcm_substream *substream,
1337 			     snd_pcm_state_t state)
1338 {
1339 	struct snd_pcm_runtime *runtime = substream->runtime;
1340 	if (runtime->status->state != SNDRV_PCM_STATE_PREPARED)
1341 		return -EBADFD;
1342 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
1343 	    !snd_pcm_playback_data(substream))
1344 		return -EPIPE;
1345 	runtime->trigger_tstamp_latched = false;
1346 	runtime->trigger_master = substream;
1347 	return 0;
1348 }
1349 
1350 static int snd_pcm_do_start(struct snd_pcm_substream *substream,
1351 			    snd_pcm_state_t state)
1352 {
1353 	if (substream->runtime->trigger_master != substream)
1354 		return 0;
1355 	return substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_START);
1356 }
1357 
1358 static void snd_pcm_undo_start(struct snd_pcm_substream *substream,
1359 			       snd_pcm_state_t state)
1360 {
1361 	if (substream->runtime->trigger_master == substream)
1362 		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_STOP);
1363 }
1364 
1365 static void snd_pcm_post_start(struct snd_pcm_substream *substream,
1366 			       snd_pcm_state_t state)
1367 {
1368 	struct snd_pcm_runtime *runtime = substream->runtime;
1369 	snd_pcm_trigger_tstamp(substream);
1370 	runtime->hw_ptr_jiffies = jiffies;
1371 	runtime->hw_ptr_buffer_jiffies = (runtime->buffer_size * HZ) /
1372 							    runtime->rate;
1373 	runtime->status->state = state;
1374 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
1375 	    runtime->silence_size > 0)
1376 		snd_pcm_playback_silence(substream, ULONG_MAX);
1377 	snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MSTART);
1378 }
1379 
1380 static const struct action_ops snd_pcm_action_start = {
1381 	.pre_action = snd_pcm_pre_start,
1382 	.do_action = snd_pcm_do_start,
1383 	.undo_action = snd_pcm_undo_start,
1384 	.post_action = snd_pcm_post_start
1385 };
1386 
1387 /**
1388  * snd_pcm_start - start all linked streams
1389  * @substream: the PCM substream instance
1390  *
1391  * Return: Zero if successful, or a negative error code.
1392  * The stream lock must be acquired before calling this function.
1393  */
1394 int snd_pcm_start(struct snd_pcm_substream *substream)
1395 {
1396 	return snd_pcm_action(&snd_pcm_action_start, substream,
1397 			      SNDRV_PCM_STATE_RUNNING);
1398 }
1399 
1400 /* take the stream lock and start the streams */
1401 static int snd_pcm_start_lock_irq(struct snd_pcm_substream *substream)
1402 {
1403 	return snd_pcm_action_lock_irq(&snd_pcm_action_start, substream,
1404 				       SNDRV_PCM_STATE_RUNNING);
1405 }
1406 
1407 /*
1408  * stop callbacks
1409  */
1410 static int snd_pcm_pre_stop(struct snd_pcm_substream *substream,
1411 			    snd_pcm_state_t state)
1412 {
1413 	struct snd_pcm_runtime *runtime = substream->runtime;
1414 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1415 		return -EBADFD;
1416 	runtime->trigger_master = substream;
1417 	return 0;
1418 }
1419 
1420 static int snd_pcm_do_stop(struct snd_pcm_substream *substream,
1421 			   snd_pcm_state_t state)
1422 {
1423 	if (substream->runtime->trigger_master == substream &&
1424 	    snd_pcm_running(substream))
1425 		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_STOP);
1426 	return 0; /* unconditonally stop all substreams */
1427 }
1428 
1429 static void snd_pcm_post_stop(struct snd_pcm_substream *substream,
1430 			      snd_pcm_state_t state)
1431 {
1432 	struct snd_pcm_runtime *runtime = substream->runtime;
1433 	if (runtime->status->state != state) {
1434 		snd_pcm_trigger_tstamp(substream);
1435 		runtime->status->state = state;
1436 		snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MSTOP);
1437 	}
1438 	runtime->stop_operating = true;
1439 	wake_up(&runtime->sleep);
1440 	wake_up(&runtime->tsleep);
1441 }
1442 
1443 static const struct action_ops snd_pcm_action_stop = {
1444 	.pre_action = snd_pcm_pre_stop,
1445 	.do_action = snd_pcm_do_stop,
1446 	.post_action = snd_pcm_post_stop
1447 };
1448 
1449 /**
1450  * snd_pcm_stop - try to stop all running streams in the substream group
1451  * @substream: the PCM substream instance
1452  * @state: PCM state after stopping the stream
1453  *
1454  * The state of each stream is then changed to the given state unconditionally.
1455  *
1456  * Return: Zero if successful, or a negative error code.
1457  */
1458 int snd_pcm_stop(struct snd_pcm_substream *substream, snd_pcm_state_t state)
1459 {
1460 	return snd_pcm_action(&snd_pcm_action_stop, substream, state);
1461 }
1462 EXPORT_SYMBOL(snd_pcm_stop);
1463 
1464 /**
1465  * snd_pcm_drain_done - stop the DMA only when the given stream is playback
1466  * @substream: the PCM substream
1467  *
1468  * After stopping, the state is changed to SETUP.
1469  * Unlike snd_pcm_stop(), this affects only the given stream.
1470  *
1471  * Return: Zero if succesful, or a negative error code.
1472  */
1473 int snd_pcm_drain_done(struct snd_pcm_substream *substream)
1474 {
1475 	return snd_pcm_action_single(&snd_pcm_action_stop, substream,
1476 				     SNDRV_PCM_STATE_SETUP);
1477 }
1478 
1479 /**
1480  * snd_pcm_stop_xrun - stop the running streams as XRUN
1481  * @substream: the PCM substream instance
1482  *
1483  * This stops the given running substream (and all linked substreams) as XRUN.
1484  * Unlike snd_pcm_stop(), this function takes the substream lock by itself.
1485  *
1486  * Return: Zero if successful, or a negative error code.
1487  */
1488 int snd_pcm_stop_xrun(struct snd_pcm_substream *substream)
1489 {
1490 	unsigned long flags;
1491 
1492 	snd_pcm_stream_lock_irqsave(substream, flags);
1493 	if (substream->runtime && snd_pcm_running(substream))
1494 		__snd_pcm_xrun(substream);
1495 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1496 	return 0;
1497 }
1498 EXPORT_SYMBOL_GPL(snd_pcm_stop_xrun);
1499 
1500 /*
1501  * pause callbacks: pass boolean (to start pause or resume) as state argument
1502  */
1503 #define pause_pushed(state)	(__force bool)(state)
1504 
1505 static int snd_pcm_pre_pause(struct snd_pcm_substream *substream,
1506 			     snd_pcm_state_t state)
1507 {
1508 	struct snd_pcm_runtime *runtime = substream->runtime;
1509 	if (!(runtime->info & SNDRV_PCM_INFO_PAUSE))
1510 		return -ENOSYS;
1511 	if (pause_pushed(state)) {
1512 		if (runtime->status->state != SNDRV_PCM_STATE_RUNNING)
1513 			return -EBADFD;
1514 	} else if (runtime->status->state != SNDRV_PCM_STATE_PAUSED)
1515 		return -EBADFD;
1516 	runtime->trigger_master = substream;
1517 	return 0;
1518 }
1519 
1520 static int snd_pcm_do_pause(struct snd_pcm_substream *substream,
1521 			    snd_pcm_state_t state)
1522 {
1523 	if (substream->runtime->trigger_master != substream)
1524 		return 0;
1525 	/* some drivers might use hw_ptr to recover from the pause -
1526 	   update the hw_ptr now */
1527 	if (pause_pushed(state))
1528 		snd_pcm_update_hw_ptr(substream);
1529 	/* The jiffies check in snd_pcm_update_hw_ptr*() is done by
1530 	 * a delta between the current jiffies, this gives a large enough
1531 	 * delta, effectively to skip the check once.
1532 	 */
1533 	substream->runtime->hw_ptr_jiffies = jiffies - HZ * 1000;
1534 	return substream->ops->trigger(substream,
1535 				       pause_pushed(state) ?
1536 				       SNDRV_PCM_TRIGGER_PAUSE_PUSH :
1537 				       SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
1538 }
1539 
1540 static void snd_pcm_undo_pause(struct snd_pcm_substream *substream,
1541 			       snd_pcm_state_t state)
1542 {
1543 	if (substream->runtime->trigger_master == substream)
1544 		substream->ops->trigger(substream,
1545 					pause_pushed(state) ?
1546 					SNDRV_PCM_TRIGGER_PAUSE_RELEASE :
1547 					SNDRV_PCM_TRIGGER_PAUSE_PUSH);
1548 }
1549 
1550 static void snd_pcm_post_pause(struct snd_pcm_substream *substream,
1551 			       snd_pcm_state_t state)
1552 {
1553 	struct snd_pcm_runtime *runtime = substream->runtime;
1554 	snd_pcm_trigger_tstamp(substream);
1555 	if (pause_pushed(state)) {
1556 		runtime->status->state = SNDRV_PCM_STATE_PAUSED;
1557 		snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MPAUSE);
1558 		wake_up(&runtime->sleep);
1559 		wake_up(&runtime->tsleep);
1560 	} else {
1561 		runtime->status->state = SNDRV_PCM_STATE_RUNNING;
1562 		snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MCONTINUE);
1563 	}
1564 }
1565 
1566 static const struct action_ops snd_pcm_action_pause = {
1567 	.pre_action = snd_pcm_pre_pause,
1568 	.do_action = snd_pcm_do_pause,
1569 	.undo_action = snd_pcm_undo_pause,
1570 	.post_action = snd_pcm_post_pause
1571 };
1572 
1573 /*
1574  * Push/release the pause for all linked streams.
1575  */
1576 static int snd_pcm_pause(struct snd_pcm_substream *substream, bool push)
1577 {
1578 	return snd_pcm_action(&snd_pcm_action_pause, substream,
1579 			      (__force snd_pcm_state_t)push);
1580 }
1581 
1582 static int snd_pcm_pause_lock_irq(struct snd_pcm_substream *substream,
1583 				  bool push)
1584 {
1585 	return snd_pcm_action_lock_irq(&snd_pcm_action_pause, substream,
1586 				       (__force snd_pcm_state_t)push);
1587 }
1588 
1589 #ifdef CONFIG_PM
1590 /* suspend callback: state argument ignored */
1591 
1592 static int snd_pcm_pre_suspend(struct snd_pcm_substream *substream,
1593 			       snd_pcm_state_t state)
1594 {
1595 	struct snd_pcm_runtime *runtime = substream->runtime;
1596 	switch (runtime->status->state) {
1597 	case SNDRV_PCM_STATE_SUSPENDED:
1598 		return -EBUSY;
1599 	/* unresumable PCM state; return -EBUSY for skipping suspend */
1600 	case SNDRV_PCM_STATE_OPEN:
1601 	case SNDRV_PCM_STATE_SETUP:
1602 	case SNDRV_PCM_STATE_DISCONNECTED:
1603 		return -EBUSY;
1604 	}
1605 	runtime->trigger_master = substream;
1606 	return 0;
1607 }
1608 
1609 static int snd_pcm_do_suspend(struct snd_pcm_substream *substream,
1610 			      snd_pcm_state_t state)
1611 {
1612 	struct snd_pcm_runtime *runtime = substream->runtime;
1613 	if (runtime->trigger_master != substream)
1614 		return 0;
1615 	if (! snd_pcm_running(substream))
1616 		return 0;
1617 	substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_SUSPEND);
1618 	return 0; /* suspend unconditionally */
1619 }
1620 
1621 static void snd_pcm_post_suspend(struct snd_pcm_substream *substream,
1622 				 snd_pcm_state_t state)
1623 {
1624 	struct snd_pcm_runtime *runtime = substream->runtime;
1625 	snd_pcm_trigger_tstamp(substream);
1626 	runtime->status->suspended_state = runtime->status->state;
1627 	runtime->status->state = SNDRV_PCM_STATE_SUSPENDED;
1628 	snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MSUSPEND);
1629 	wake_up(&runtime->sleep);
1630 	wake_up(&runtime->tsleep);
1631 }
1632 
1633 static const struct action_ops snd_pcm_action_suspend = {
1634 	.pre_action = snd_pcm_pre_suspend,
1635 	.do_action = snd_pcm_do_suspend,
1636 	.post_action = snd_pcm_post_suspend
1637 };
1638 
1639 /*
1640  * snd_pcm_suspend - trigger SUSPEND to all linked streams
1641  * @substream: the PCM substream
1642  *
1643  * After this call, all streams are changed to SUSPENDED state.
1644  *
1645  * Return: Zero if successful, or a negative error code.
1646  */
1647 static int snd_pcm_suspend(struct snd_pcm_substream *substream)
1648 {
1649 	int err;
1650 	unsigned long flags;
1651 
1652 	snd_pcm_stream_lock_irqsave(substream, flags);
1653 	err = snd_pcm_action(&snd_pcm_action_suspend, substream,
1654 			     ACTION_ARG_IGNORE);
1655 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1656 	return err;
1657 }
1658 
1659 /**
1660  * snd_pcm_suspend_all - trigger SUSPEND to all substreams in the given pcm
1661  * @pcm: the PCM instance
1662  *
1663  * After this call, all streams are changed to SUSPENDED state.
1664  *
1665  * Return: Zero if successful (or @pcm is %NULL), or a negative error code.
1666  */
1667 int snd_pcm_suspend_all(struct snd_pcm *pcm)
1668 {
1669 	struct snd_pcm_substream *substream;
1670 	int stream, err = 0;
1671 
1672 	if (! pcm)
1673 		return 0;
1674 
1675 	for (stream = 0; stream < 2; stream++) {
1676 		for (substream = pcm->streams[stream].substream;
1677 		     substream; substream = substream->next) {
1678 			/* FIXME: the open/close code should lock this as well */
1679 			if (substream->runtime == NULL)
1680 				continue;
1681 
1682 			/*
1683 			 * Skip BE dai link PCM's that are internal and may
1684 			 * not have their substream ops set.
1685 			 */
1686 			if (!substream->ops)
1687 				continue;
1688 
1689 			err = snd_pcm_suspend(substream);
1690 			if (err < 0 && err != -EBUSY)
1691 				return err;
1692 		}
1693 	}
1694 	return 0;
1695 }
1696 EXPORT_SYMBOL(snd_pcm_suspend_all);
1697 
1698 /* resume callbacks: state argument ignored */
1699 
1700 static int snd_pcm_pre_resume(struct snd_pcm_substream *substream,
1701 			      snd_pcm_state_t state)
1702 {
1703 	struct snd_pcm_runtime *runtime = substream->runtime;
1704 	if (!(runtime->info & SNDRV_PCM_INFO_RESUME))
1705 		return -ENOSYS;
1706 	runtime->trigger_master = substream;
1707 	return 0;
1708 }
1709 
1710 static int snd_pcm_do_resume(struct snd_pcm_substream *substream,
1711 			     snd_pcm_state_t state)
1712 {
1713 	struct snd_pcm_runtime *runtime = substream->runtime;
1714 	if (runtime->trigger_master != substream)
1715 		return 0;
1716 	/* DMA not running previously? */
1717 	if (runtime->status->suspended_state != SNDRV_PCM_STATE_RUNNING &&
1718 	    (runtime->status->suspended_state != SNDRV_PCM_STATE_DRAINING ||
1719 	     substream->stream != SNDRV_PCM_STREAM_PLAYBACK))
1720 		return 0;
1721 	return substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_RESUME);
1722 }
1723 
1724 static void snd_pcm_undo_resume(struct snd_pcm_substream *substream,
1725 				snd_pcm_state_t state)
1726 {
1727 	if (substream->runtime->trigger_master == substream &&
1728 	    snd_pcm_running(substream))
1729 		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_SUSPEND);
1730 }
1731 
1732 static void snd_pcm_post_resume(struct snd_pcm_substream *substream,
1733 				snd_pcm_state_t state)
1734 {
1735 	struct snd_pcm_runtime *runtime = substream->runtime;
1736 	snd_pcm_trigger_tstamp(substream);
1737 	runtime->status->state = runtime->status->suspended_state;
1738 	snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MRESUME);
1739 	snd_pcm_sync_stop(substream);
1740 }
1741 
1742 static const struct action_ops snd_pcm_action_resume = {
1743 	.pre_action = snd_pcm_pre_resume,
1744 	.do_action = snd_pcm_do_resume,
1745 	.undo_action = snd_pcm_undo_resume,
1746 	.post_action = snd_pcm_post_resume
1747 };
1748 
1749 static int snd_pcm_resume(struct snd_pcm_substream *substream)
1750 {
1751 	return snd_pcm_action_lock_irq(&snd_pcm_action_resume, substream,
1752 				       ACTION_ARG_IGNORE);
1753 }
1754 
1755 #else
1756 
1757 static int snd_pcm_resume(struct snd_pcm_substream *substream)
1758 {
1759 	return -ENOSYS;
1760 }
1761 
1762 #endif /* CONFIG_PM */
1763 
1764 /*
1765  * xrun ioctl
1766  *
1767  * Change the RUNNING stream(s) to XRUN state.
1768  */
1769 static int snd_pcm_xrun(struct snd_pcm_substream *substream)
1770 {
1771 	struct snd_pcm_runtime *runtime = substream->runtime;
1772 	int result;
1773 
1774 	snd_pcm_stream_lock_irq(substream);
1775 	switch (runtime->status->state) {
1776 	case SNDRV_PCM_STATE_XRUN:
1777 		result = 0;	/* already there */
1778 		break;
1779 	case SNDRV_PCM_STATE_RUNNING:
1780 		__snd_pcm_xrun(substream);
1781 		result = 0;
1782 		break;
1783 	default:
1784 		result = -EBADFD;
1785 	}
1786 	snd_pcm_stream_unlock_irq(substream);
1787 	return result;
1788 }
1789 
1790 /*
1791  * reset ioctl
1792  */
1793 /* reset callbacks:  state argument ignored */
1794 static int snd_pcm_pre_reset(struct snd_pcm_substream *substream,
1795 			     snd_pcm_state_t state)
1796 {
1797 	struct snd_pcm_runtime *runtime = substream->runtime;
1798 	switch (runtime->status->state) {
1799 	case SNDRV_PCM_STATE_RUNNING:
1800 	case SNDRV_PCM_STATE_PREPARED:
1801 	case SNDRV_PCM_STATE_PAUSED:
1802 	case SNDRV_PCM_STATE_SUSPENDED:
1803 		return 0;
1804 	default:
1805 		return -EBADFD;
1806 	}
1807 }
1808 
1809 static int snd_pcm_do_reset(struct snd_pcm_substream *substream,
1810 			    snd_pcm_state_t state)
1811 {
1812 	struct snd_pcm_runtime *runtime = substream->runtime;
1813 	int err = snd_pcm_ops_ioctl(substream, SNDRV_PCM_IOCTL1_RESET, NULL);
1814 	if (err < 0)
1815 		return err;
1816 	runtime->hw_ptr_base = 0;
1817 	runtime->hw_ptr_interrupt = runtime->status->hw_ptr -
1818 		runtime->status->hw_ptr % runtime->period_size;
1819 	runtime->silence_start = runtime->status->hw_ptr;
1820 	runtime->silence_filled = 0;
1821 	return 0;
1822 }
1823 
1824 static void snd_pcm_post_reset(struct snd_pcm_substream *substream,
1825 			       snd_pcm_state_t state)
1826 {
1827 	struct snd_pcm_runtime *runtime = substream->runtime;
1828 	runtime->control->appl_ptr = runtime->status->hw_ptr;
1829 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
1830 	    runtime->silence_size > 0)
1831 		snd_pcm_playback_silence(substream, ULONG_MAX);
1832 }
1833 
1834 static const struct action_ops snd_pcm_action_reset = {
1835 	.pre_action = snd_pcm_pre_reset,
1836 	.do_action = snd_pcm_do_reset,
1837 	.post_action = snd_pcm_post_reset
1838 };
1839 
1840 static int snd_pcm_reset(struct snd_pcm_substream *substream)
1841 {
1842 	return snd_pcm_action_nonatomic(&snd_pcm_action_reset, substream,
1843 					ACTION_ARG_IGNORE);
1844 }
1845 
1846 /*
1847  * prepare ioctl
1848  */
1849 /* pass f_flags as state argument */
1850 static int snd_pcm_pre_prepare(struct snd_pcm_substream *substream,
1851 			       snd_pcm_state_t state)
1852 {
1853 	struct snd_pcm_runtime *runtime = substream->runtime;
1854 	int f_flags = (__force int)state;
1855 
1856 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN ||
1857 	    runtime->status->state == SNDRV_PCM_STATE_DISCONNECTED)
1858 		return -EBADFD;
1859 	if (snd_pcm_running(substream))
1860 		return -EBUSY;
1861 	substream->f_flags = f_flags;
1862 	return 0;
1863 }
1864 
1865 static int snd_pcm_do_prepare(struct snd_pcm_substream *substream,
1866 			      snd_pcm_state_t state)
1867 {
1868 	int err;
1869 	snd_pcm_sync_stop(substream);
1870 	err = substream->ops->prepare(substream);
1871 	if (err < 0)
1872 		return err;
1873 	return snd_pcm_do_reset(substream, state);
1874 }
1875 
1876 static void snd_pcm_post_prepare(struct snd_pcm_substream *substream,
1877 				 snd_pcm_state_t state)
1878 {
1879 	struct snd_pcm_runtime *runtime = substream->runtime;
1880 	runtime->control->appl_ptr = runtime->status->hw_ptr;
1881 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_PREPARED);
1882 }
1883 
1884 static const struct action_ops snd_pcm_action_prepare = {
1885 	.pre_action = snd_pcm_pre_prepare,
1886 	.do_action = snd_pcm_do_prepare,
1887 	.post_action = snd_pcm_post_prepare
1888 };
1889 
1890 /**
1891  * snd_pcm_prepare - prepare the PCM substream to be triggerable
1892  * @substream: the PCM substream instance
1893  * @file: file to refer f_flags
1894  *
1895  * Return: Zero if successful, or a negative error code.
1896  */
1897 static int snd_pcm_prepare(struct snd_pcm_substream *substream,
1898 			   struct file *file)
1899 {
1900 	int f_flags;
1901 
1902 	if (file)
1903 		f_flags = file->f_flags;
1904 	else
1905 		f_flags = substream->f_flags;
1906 
1907 	snd_pcm_stream_lock_irq(substream);
1908 	switch (substream->runtime->status->state) {
1909 	case SNDRV_PCM_STATE_PAUSED:
1910 		snd_pcm_pause(substream, false);
1911 		fallthrough;
1912 	case SNDRV_PCM_STATE_SUSPENDED:
1913 		snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
1914 		break;
1915 	}
1916 	snd_pcm_stream_unlock_irq(substream);
1917 
1918 	return snd_pcm_action_nonatomic(&snd_pcm_action_prepare,
1919 					substream,
1920 					(__force snd_pcm_state_t)f_flags);
1921 }
1922 
1923 /*
1924  * drain ioctl
1925  */
1926 
1927 /* drain init callbacks: state argument ignored */
1928 static int snd_pcm_pre_drain_init(struct snd_pcm_substream *substream,
1929 				  snd_pcm_state_t state)
1930 {
1931 	struct snd_pcm_runtime *runtime = substream->runtime;
1932 	switch (runtime->status->state) {
1933 	case SNDRV_PCM_STATE_OPEN:
1934 	case SNDRV_PCM_STATE_DISCONNECTED:
1935 	case SNDRV_PCM_STATE_SUSPENDED:
1936 		return -EBADFD;
1937 	}
1938 	runtime->trigger_master = substream;
1939 	return 0;
1940 }
1941 
1942 static int snd_pcm_do_drain_init(struct snd_pcm_substream *substream,
1943 				 snd_pcm_state_t state)
1944 {
1945 	struct snd_pcm_runtime *runtime = substream->runtime;
1946 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
1947 		switch (runtime->status->state) {
1948 		case SNDRV_PCM_STATE_PREPARED:
1949 			/* start playback stream if possible */
1950 			if (! snd_pcm_playback_empty(substream)) {
1951 				snd_pcm_do_start(substream, SNDRV_PCM_STATE_DRAINING);
1952 				snd_pcm_post_start(substream, SNDRV_PCM_STATE_DRAINING);
1953 			} else {
1954 				runtime->status->state = SNDRV_PCM_STATE_SETUP;
1955 			}
1956 			break;
1957 		case SNDRV_PCM_STATE_RUNNING:
1958 			runtime->status->state = SNDRV_PCM_STATE_DRAINING;
1959 			break;
1960 		case SNDRV_PCM_STATE_XRUN:
1961 			runtime->status->state = SNDRV_PCM_STATE_SETUP;
1962 			break;
1963 		default:
1964 			break;
1965 		}
1966 	} else {
1967 		/* stop running stream */
1968 		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING) {
1969 			snd_pcm_state_t new_state;
1970 
1971 			new_state = snd_pcm_capture_avail(runtime) > 0 ?
1972 				SNDRV_PCM_STATE_DRAINING : SNDRV_PCM_STATE_SETUP;
1973 			snd_pcm_do_stop(substream, new_state);
1974 			snd_pcm_post_stop(substream, new_state);
1975 		}
1976 	}
1977 
1978 	if (runtime->status->state == SNDRV_PCM_STATE_DRAINING &&
1979 	    runtime->trigger_master == substream &&
1980 	    (runtime->hw.info & SNDRV_PCM_INFO_DRAIN_TRIGGER))
1981 		return substream->ops->trigger(substream,
1982 					       SNDRV_PCM_TRIGGER_DRAIN);
1983 
1984 	return 0;
1985 }
1986 
1987 static void snd_pcm_post_drain_init(struct snd_pcm_substream *substream,
1988 				    snd_pcm_state_t state)
1989 {
1990 }
1991 
1992 static const struct action_ops snd_pcm_action_drain_init = {
1993 	.pre_action = snd_pcm_pre_drain_init,
1994 	.do_action = snd_pcm_do_drain_init,
1995 	.post_action = snd_pcm_post_drain_init
1996 };
1997 
1998 /*
1999  * Drain the stream(s).
2000  * When the substream is linked, sync until the draining of all playback streams
2001  * is finished.
2002  * After this call, all streams are supposed to be either SETUP or DRAINING
2003  * (capture only) state.
2004  */
2005 static int snd_pcm_drain(struct snd_pcm_substream *substream,
2006 			 struct file *file)
2007 {
2008 	struct snd_card *card;
2009 	struct snd_pcm_runtime *runtime;
2010 	struct snd_pcm_substream *s;
2011 	struct snd_pcm_group *group;
2012 	wait_queue_entry_t wait;
2013 	int result = 0;
2014 	int nonblock = 0;
2015 
2016 	card = substream->pcm->card;
2017 	runtime = substream->runtime;
2018 
2019 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2020 		return -EBADFD;
2021 
2022 	if (file) {
2023 		if (file->f_flags & O_NONBLOCK)
2024 			nonblock = 1;
2025 	} else if (substream->f_flags & O_NONBLOCK)
2026 		nonblock = 1;
2027 
2028 	snd_pcm_stream_lock_irq(substream);
2029 	/* resume pause */
2030 	if (runtime->status->state == SNDRV_PCM_STATE_PAUSED)
2031 		snd_pcm_pause(substream, false);
2032 
2033 	/* pre-start/stop - all running streams are changed to DRAINING state */
2034 	result = snd_pcm_action(&snd_pcm_action_drain_init, substream,
2035 				ACTION_ARG_IGNORE);
2036 	if (result < 0)
2037 		goto unlock;
2038 	/* in non-blocking, we don't wait in ioctl but let caller poll */
2039 	if (nonblock) {
2040 		result = -EAGAIN;
2041 		goto unlock;
2042 	}
2043 
2044 	for (;;) {
2045 		long tout;
2046 		struct snd_pcm_runtime *to_check;
2047 		if (signal_pending(current)) {
2048 			result = -ERESTARTSYS;
2049 			break;
2050 		}
2051 		/* find a substream to drain */
2052 		to_check = NULL;
2053 		group = snd_pcm_stream_group_ref(substream);
2054 		snd_pcm_group_for_each_entry(s, substream) {
2055 			if (s->stream != SNDRV_PCM_STREAM_PLAYBACK)
2056 				continue;
2057 			runtime = s->runtime;
2058 			if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
2059 				to_check = runtime;
2060 				break;
2061 			}
2062 		}
2063 		snd_pcm_group_unref(group, substream);
2064 		if (!to_check)
2065 			break; /* all drained */
2066 		init_waitqueue_entry(&wait, current);
2067 		set_current_state(TASK_INTERRUPTIBLE);
2068 		add_wait_queue(&to_check->sleep, &wait);
2069 		snd_pcm_stream_unlock_irq(substream);
2070 		if (runtime->no_period_wakeup)
2071 			tout = MAX_SCHEDULE_TIMEOUT;
2072 		else {
2073 			tout = 10;
2074 			if (runtime->rate) {
2075 				long t = runtime->period_size * 2 / runtime->rate;
2076 				tout = max(t, tout);
2077 			}
2078 			tout = msecs_to_jiffies(tout * 1000);
2079 		}
2080 		tout = schedule_timeout(tout);
2081 
2082 		snd_pcm_stream_lock_irq(substream);
2083 		group = snd_pcm_stream_group_ref(substream);
2084 		snd_pcm_group_for_each_entry(s, substream) {
2085 			if (s->runtime == to_check) {
2086 				remove_wait_queue(&to_check->sleep, &wait);
2087 				break;
2088 			}
2089 		}
2090 		snd_pcm_group_unref(group, substream);
2091 
2092 		if (card->shutdown) {
2093 			result = -ENODEV;
2094 			break;
2095 		}
2096 		if (tout == 0) {
2097 			if (substream->runtime->status->state == SNDRV_PCM_STATE_SUSPENDED)
2098 				result = -ESTRPIPE;
2099 			else {
2100 				dev_dbg(substream->pcm->card->dev,
2101 					"playback drain error (DMA or IRQ trouble?)\n");
2102 				snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2103 				result = -EIO;
2104 			}
2105 			break;
2106 		}
2107 	}
2108 
2109  unlock:
2110 	snd_pcm_stream_unlock_irq(substream);
2111 
2112 	return result;
2113 }
2114 
2115 /*
2116  * drop ioctl
2117  *
2118  * Immediately put all linked substreams into SETUP state.
2119  */
2120 static int snd_pcm_drop(struct snd_pcm_substream *substream)
2121 {
2122 	struct snd_pcm_runtime *runtime;
2123 	int result = 0;
2124 
2125 	if (PCM_RUNTIME_CHECK(substream))
2126 		return -ENXIO;
2127 	runtime = substream->runtime;
2128 
2129 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN ||
2130 	    runtime->status->state == SNDRV_PCM_STATE_DISCONNECTED)
2131 		return -EBADFD;
2132 
2133 	snd_pcm_stream_lock_irq(substream);
2134 	/* resume pause */
2135 	if (runtime->status->state == SNDRV_PCM_STATE_PAUSED)
2136 		snd_pcm_pause(substream, false);
2137 
2138 	snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2139 	/* runtime->control->appl_ptr = runtime->status->hw_ptr; */
2140 	snd_pcm_stream_unlock_irq(substream);
2141 
2142 	return result;
2143 }
2144 
2145 
2146 static bool is_pcm_file(struct file *file)
2147 {
2148 	struct inode *inode = file_inode(file);
2149 	struct snd_pcm *pcm;
2150 	unsigned int minor;
2151 
2152 	if (!S_ISCHR(inode->i_mode) || imajor(inode) != snd_major)
2153 		return false;
2154 	minor = iminor(inode);
2155 	pcm = snd_lookup_minor_data(minor, SNDRV_DEVICE_TYPE_PCM_PLAYBACK);
2156 	if (!pcm)
2157 		pcm = snd_lookup_minor_data(minor, SNDRV_DEVICE_TYPE_PCM_CAPTURE);
2158 	if (!pcm)
2159 		return false;
2160 	snd_card_unref(pcm->card);
2161 	return true;
2162 }
2163 
2164 /*
2165  * PCM link handling
2166  */
2167 static int snd_pcm_link(struct snd_pcm_substream *substream, int fd)
2168 {
2169 	int res = 0;
2170 	struct snd_pcm_file *pcm_file;
2171 	struct snd_pcm_substream *substream1;
2172 	struct snd_pcm_group *group, *target_group;
2173 	bool nonatomic = substream->pcm->nonatomic;
2174 	struct fd f = fdget(fd);
2175 
2176 	if (!f.file)
2177 		return -EBADFD;
2178 	if (!is_pcm_file(f.file)) {
2179 		res = -EBADFD;
2180 		goto _badf;
2181 	}
2182 	pcm_file = f.file->private_data;
2183 	substream1 = pcm_file->substream;
2184 
2185 	if (substream == substream1) {
2186 		res = -EINVAL;
2187 		goto _badf;
2188 	}
2189 
2190 	group = kzalloc(sizeof(*group), GFP_KERNEL);
2191 	if (!group) {
2192 		res = -ENOMEM;
2193 		goto _nolock;
2194 	}
2195 	snd_pcm_group_init(group);
2196 
2197 	down_write(&snd_pcm_link_rwsem);
2198 	if (substream->runtime->status->state == SNDRV_PCM_STATE_OPEN ||
2199 	    substream->runtime->status->state != substream1->runtime->status->state ||
2200 	    substream->pcm->nonatomic != substream1->pcm->nonatomic) {
2201 		res = -EBADFD;
2202 		goto _end;
2203 	}
2204 	if (snd_pcm_stream_linked(substream1)) {
2205 		res = -EALREADY;
2206 		goto _end;
2207 	}
2208 
2209 	snd_pcm_stream_lock_irq(substream);
2210 	if (!snd_pcm_stream_linked(substream)) {
2211 		snd_pcm_group_assign(substream, group);
2212 		group = NULL; /* assigned, don't free this one below */
2213 	}
2214 	target_group = substream->group;
2215 	snd_pcm_stream_unlock_irq(substream);
2216 
2217 	snd_pcm_group_lock_irq(target_group, nonatomic);
2218 	snd_pcm_stream_lock_nested(substream1);
2219 	snd_pcm_group_assign(substream1, target_group);
2220 	refcount_inc(&target_group->refs);
2221 	snd_pcm_stream_unlock(substream1);
2222 	snd_pcm_group_unlock_irq(target_group, nonatomic);
2223  _end:
2224 	up_write(&snd_pcm_link_rwsem);
2225  _nolock:
2226 	kfree(group);
2227  _badf:
2228 	fdput(f);
2229 	return res;
2230 }
2231 
2232 static void relink_to_local(struct snd_pcm_substream *substream)
2233 {
2234 	snd_pcm_stream_lock_nested(substream);
2235 	snd_pcm_group_assign(substream, &substream->self_group);
2236 	snd_pcm_stream_unlock(substream);
2237 }
2238 
2239 static int snd_pcm_unlink(struct snd_pcm_substream *substream)
2240 {
2241 	struct snd_pcm_group *group;
2242 	bool nonatomic = substream->pcm->nonatomic;
2243 	bool do_free = false;
2244 	int res = 0;
2245 
2246 	down_write(&snd_pcm_link_rwsem);
2247 
2248 	if (!snd_pcm_stream_linked(substream)) {
2249 		res = -EALREADY;
2250 		goto _end;
2251 	}
2252 
2253 	group = substream->group;
2254 	snd_pcm_group_lock_irq(group, nonatomic);
2255 
2256 	relink_to_local(substream);
2257 	refcount_dec(&group->refs);
2258 
2259 	/* detach the last stream, too */
2260 	if (list_is_singular(&group->substreams)) {
2261 		relink_to_local(list_first_entry(&group->substreams,
2262 						 struct snd_pcm_substream,
2263 						 link_list));
2264 		do_free = refcount_dec_and_test(&group->refs);
2265 	}
2266 
2267 	snd_pcm_group_unlock_irq(group, nonatomic);
2268 	if (do_free)
2269 		kfree(group);
2270 
2271        _end:
2272 	up_write(&snd_pcm_link_rwsem);
2273 	return res;
2274 }
2275 
2276 /*
2277  * hw configurator
2278  */
2279 static int snd_pcm_hw_rule_mul(struct snd_pcm_hw_params *params,
2280 			       struct snd_pcm_hw_rule *rule)
2281 {
2282 	struct snd_interval t;
2283 	snd_interval_mul(hw_param_interval_c(params, rule->deps[0]),
2284 		     hw_param_interval_c(params, rule->deps[1]), &t);
2285 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2286 }
2287 
2288 static int snd_pcm_hw_rule_div(struct snd_pcm_hw_params *params,
2289 			       struct snd_pcm_hw_rule *rule)
2290 {
2291 	struct snd_interval t;
2292 	snd_interval_div(hw_param_interval_c(params, rule->deps[0]),
2293 		     hw_param_interval_c(params, rule->deps[1]), &t);
2294 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2295 }
2296 
2297 static int snd_pcm_hw_rule_muldivk(struct snd_pcm_hw_params *params,
2298 				   struct snd_pcm_hw_rule *rule)
2299 {
2300 	struct snd_interval t;
2301 	snd_interval_muldivk(hw_param_interval_c(params, rule->deps[0]),
2302 			 hw_param_interval_c(params, rule->deps[1]),
2303 			 (unsigned long) rule->private, &t);
2304 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2305 }
2306 
2307 static int snd_pcm_hw_rule_mulkdiv(struct snd_pcm_hw_params *params,
2308 				   struct snd_pcm_hw_rule *rule)
2309 {
2310 	struct snd_interval t;
2311 	snd_interval_mulkdiv(hw_param_interval_c(params, rule->deps[0]),
2312 			 (unsigned long) rule->private,
2313 			 hw_param_interval_c(params, rule->deps[1]), &t);
2314 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2315 }
2316 
2317 static int snd_pcm_hw_rule_format(struct snd_pcm_hw_params *params,
2318 				  struct snd_pcm_hw_rule *rule)
2319 {
2320 	snd_pcm_format_t k;
2321 	const struct snd_interval *i =
2322 				hw_param_interval_c(params, rule->deps[0]);
2323 	struct snd_mask m;
2324 	struct snd_mask *mask = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
2325 	snd_mask_any(&m);
2326 	pcm_for_each_format(k) {
2327 		int bits;
2328 		if (!snd_mask_test_format(mask, k))
2329 			continue;
2330 		bits = snd_pcm_format_physical_width(k);
2331 		if (bits <= 0)
2332 			continue; /* ignore invalid formats */
2333 		if ((unsigned)bits < i->min || (unsigned)bits > i->max)
2334 			snd_mask_reset(&m, (__force unsigned)k);
2335 	}
2336 	return snd_mask_refine(mask, &m);
2337 }
2338 
2339 static int snd_pcm_hw_rule_sample_bits(struct snd_pcm_hw_params *params,
2340 				       struct snd_pcm_hw_rule *rule)
2341 {
2342 	struct snd_interval t;
2343 	snd_pcm_format_t k;
2344 
2345 	t.min = UINT_MAX;
2346 	t.max = 0;
2347 	t.openmin = 0;
2348 	t.openmax = 0;
2349 	pcm_for_each_format(k) {
2350 		int bits;
2351 		if (!snd_mask_test_format(hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT), k))
2352 			continue;
2353 		bits = snd_pcm_format_physical_width(k);
2354 		if (bits <= 0)
2355 			continue; /* ignore invalid formats */
2356 		if (t.min > (unsigned)bits)
2357 			t.min = bits;
2358 		if (t.max < (unsigned)bits)
2359 			t.max = bits;
2360 	}
2361 	t.integer = 1;
2362 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2363 }
2364 
2365 #if SNDRV_PCM_RATE_5512 != 1 << 0 || SNDRV_PCM_RATE_192000 != 1 << 12
2366 #error "Change this table"
2367 #endif
2368 
2369 static const unsigned int rates[] = {
2370 	5512, 8000, 11025, 16000, 22050, 32000, 44100,
2371 	48000, 64000, 88200, 96000, 176400, 192000, 352800, 384000
2372 };
2373 
2374 const struct snd_pcm_hw_constraint_list snd_pcm_known_rates = {
2375 	.count = ARRAY_SIZE(rates),
2376 	.list = rates,
2377 };
2378 
2379 static int snd_pcm_hw_rule_rate(struct snd_pcm_hw_params *params,
2380 				struct snd_pcm_hw_rule *rule)
2381 {
2382 	struct snd_pcm_hardware *hw = rule->private;
2383 	return snd_interval_list(hw_param_interval(params, rule->var),
2384 				 snd_pcm_known_rates.count,
2385 				 snd_pcm_known_rates.list, hw->rates);
2386 }
2387 
2388 static int snd_pcm_hw_rule_buffer_bytes_max(struct snd_pcm_hw_params *params,
2389 					    struct snd_pcm_hw_rule *rule)
2390 {
2391 	struct snd_interval t;
2392 	struct snd_pcm_substream *substream = rule->private;
2393 	t.min = 0;
2394 	t.max = substream->buffer_bytes_max;
2395 	t.openmin = 0;
2396 	t.openmax = 0;
2397 	t.integer = 1;
2398 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2399 }
2400 
2401 static int snd_pcm_hw_constraints_init(struct snd_pcm_substream *substream)
2402 {
2403 	struct snd_pcm_runtime *runtime = substream->runtime;
2404 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
2405 	int k, err;
2406 
2407 	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++) {
2408 		snd_mask_any(constrs_mask(constrs, k));
2409 	}
2410 
2411 	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++) {
2412 		snd_interval_any(constrs_interval(constrs, k));
2413 	}
2414 
2415 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_CHANNELS));
2416 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_BUFFER_SIZE));
2417 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_BUFFER_BYTES));
2418 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_SAMPLE_BITS));
2419 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_FRAME_BITS));
2420 
2421 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
2422 				   snd_pcm_hw_rule_format, NULL,
2423 				   SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
2424 	if (err < 0)
2425 		return err;
2426 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
2427 				  snd_pcm_hw_rule_sample_bits, NULL,
2428 				  SNDRV_PCM_HW_PARAM_FORMAT,
2429 				  SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
2430 	if (err < 0)
2431 		return err;
2432 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
2433 				  snd_pcm_hw_rule_div, NULL,
2434 				  SNDRV_PCM_HW_PARAM_FRAME_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_mul, NULL,
2439 				  SNDRV_PCM_HW_PARAM_SAMPLE_BITS, SNDRV_PCM_HW_PARAM_CHANNELS, -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_PERIOD_BYTES, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
2445 	if (err < 0)
2446 		return err;
2447 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS,
2448 				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
2449 				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, -1);
2450 	if (err < 0)
2451 		return err;
2452 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
2453 				  snd_pcm_hw_rule_div, NULL,
2454 				  SNDRV_PCM_HW_PARAM_FRAME_BITS, SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -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_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_PERIOD_TIME, -1);
2460 	if (err < 0)
2461 		return err;
2462 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
2463 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2464 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_BUFFER_TIME, -1);
2465 	if (err < 0)
2466 		return err;
2467 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIODS,
2468 				  snd_pcm_hw_rule_div, NULL,
2469 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -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_div, NULL,
2474 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_PERIODS, -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_mulkdiv, (void*) 8,
2479 				  SNDRV_PCM_HW_PARAM_PERIOD_BYTES, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2480 	if (err < 0)
2481 		return err;
2482 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
2483 				  snd_pcm_hw_rule_muldivk, (void*) 1000000,
2484 				  SNDRV_PCM_HW_PARAM_PERIOD_TIME, SNDRV_PCM_HW_PARAM_RATE, -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_mul, NULL,
2489 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_PERIODS, -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_mulkdiv, (void*) 8,
2494 				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2495 	if (err < 0)
2496 		return err;
2497 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
2498 				  snd_pcm_hw_rule_muldivk, (void*) 1000000,
2499 				  SNDRV_PCM_HW_PARAM_BUFFER_TIME, SNDRV_PCM_HW_PARAM_RATE, -1);
2500 	if (err < 0)
2501 		return err;
2502 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
2503 				  snd_pcm_hw_rule_muldivk, (void*) 8,
2504 				  SNDRV_PCM_HW_PARAM_PERIOD_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_BUFFER_BYTES,
2508 				  snd_pcm_hw_rule_muldivk, (void*) 8,
2509 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2510 	if (err < 0)
2511 		return err;
2512 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
2513 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2514 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_RATE, -1);
2515 	if (err < 0)
2516 		return err;
2517 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_TIME,
2518 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2519 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_RATE, -1);
2520 	if (err < 0)
2521 		return err;
2522 	return 0;
2523 }
2524 
2525 static int snd_pcm_hw_constraints_complete(struct snd_pcm_substream *substream)
2526 {
2527 	struct snd_pcm_runtime *runtime = substream->runtime;
2528 	struct snd_pcm_hardware *hw = &runtime->hw;
2529 	int err;
2530 	unsigned int mask = 0;
2531 
2532         if (hw->info & SNDRV_PCM_INFO_INTERLEAVED)
2533 		mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_RW_INTERLEAVED);
2534         if (hw->info & SNDRV_PCM_INFO_NONINTERLEAVED)
2535 		mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_RW_NONINTERLEAVED);
2536 	if (hw_support_mmap(substream)) {
2537 		if (hw->info & SNDRV_PCM_INFO_INTERLEAVED)
2538 			mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_MMAP_INTERLEAVED);
2539 		if (hw->info & SNDRV_PCM_INFO_NONINTERLEAVED)
2540 			mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED);
2541 		if (hw->info & SNDRV_PCM_INFO_COMPLEX)
2542 			mask |= PARAM_MASK_BIT(SNDRV_PCM_ACCESS_MMAP_COMPLEX);
2543 	}
2544 	err = snd_pcm_hw_constraint_mask(runtime, SNDRV_PCM_HW_PARAM_ACCESS, mask);
2545 	if (err < 0)
2546 		return err;
2547 
2548 	err = snd_pcm_hw_constraint_mask64(runtime, SNDRV_PCM_HW_PARAM_FORMAT, hw->formats);
2549 	if (err < 0)
2550 		return err;
2551 
2552 	err = snd_pcm_hw_constraint_mask(runtime, SNDRV_PCM_HW_PARAM_SUBFORMAT,
2553 					 PARAM_MASK_BIT(SNDRV_PCM_SUBFORMAT_STD));
2554 	if (err < 0)
2555 		return err;
2556 
2557 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_CHANNELS,
2558 					   hw->channels_min, hw->channels_max);
2559 	if (err < 0)
2560 		return err;
2561 
2562 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_RATE,
2563 					   hw->rate_min, hw->rate_max);
2564 	if (err < 0)
2565 		return err;
2566 
2567 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
2568 					   hw->period_bytes_min, hw->period_bytes_max);
2569 	if (err < 0)
2570 		return err;
2571 
2572 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIODS,
2573 					   hw->periods_min, hw->periods_max);
2574 	if (err < 0)
2575 		return err;
2576 
2577 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
2578 					   hw->period_bytes_min, hw->buffer_bytes_max);
2579 	if (err < 0)
2580 		return err;
2581 
2582 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
2583 				  snd_pcm_hw_rule_buffer_bytes_max, substream,
2584 				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, -1);
2585 	if (err < 0)
2586 		return err;
2587 
2588 	/* FIXME: remove */
2589 	if (runtime->dma_bytes) {
2590 		err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 0, runtime->dma_bytes);
2591 		if (err < 0)
2592 			return err;
2593 	}
2594 
2595 	if (!(hw->rates & (SNDRV_PCM_RATE_KNOT | SNDRV_PCM_RATE_CONTINUOUS))) {
2596 		err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
2597 					  snd_pcm_hw_rule_rate, hw,
2598 					  SNDRV_PCM_HW_PARAM_RATE, -1);
2599 		if (err < 0)
2600 			return err;
2601 	}
2602 
2603 	/* FIXME: this belong to lowlevel */
2604 	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
2605 
2606 	return 0;
2607 }
2608 
2609 static void pcm_release_private(struct snd_pcm_substream *substream)
2610 {
2611 	if (snd_pcm_stream_linked(substream))
2612 		snd_pcm_unlink(substream);
2613 }
2614 
2615 void snd_pcm_release_substream(struct snd_pcm_substream *substream)
2616 {
2617 	substream->ref_count--;
2618 	if (substream->ref_count > 0)
2619 		return;
2620 
2621 	snd_pcm_drop(substream);
2622 	if (substream->hw_opened) {
2623 		if (substream->runtime->status->state != SNDRV_PCM_STATE_OPEN)
2624 			do_hw_free(substream);
2625 		substream->ops->close(substream);
2626 		substream->hw_opened = 0;
2627 	}
2628 	if (cpu_latency_qos_request_active(&substream->latency_pm_qos_req))
2629 		cpu_latency_qos_remove_request(&substream->latency_pm_qos_req);
2630 	if (substream->pcm_release) {
2631 		substream->pcm_release(substream);
2632 		substream->pcm_release = NULL;
2633 	}
2634 	snd_pcm_detach_substream(substream);
2635 }
2636 EXPORT_SYMBOL(snd_pcm_release_substream);
2637 
2638 int snd_pcm_open_substream(struct snd_pcm *pcm, int stream,
2639 			   struct file *file,
2640 			   struct snd_pcm_substream **rsubstream)
2641 {
2642 	struct snd_pcm_substream *substream;
2643 	int err;
2644 
2645 	err = snd_pcm_attach_substream(pcm, stream, file, &substream);
2646 	if (err < 0)
2647 		return err;
2648 	if (substream->ref_count > 1) {
2649 		*rsubstream = substream;
2650 		return 0;
2651 	}
2652 
2653 	err = snd_pcm_hw_constraints_init(substream);
2654 	if (err < 0) {
2655 		pcm_dbg(pcm, "snd_pcm_hw_constraints_init failed\n");
2656 		goto error;
2657 	}
2658 
2659 	if ((err = substream->ops->open(substream)) < 0)
2660 		goto error;
2661 
2662 	substream->hw_opened = 1;
2663 
2664 	err = snd_pcm_hw_constraints_complete(substream);
2665 	if (err < 0) {
2666 		pcm_dbg(pcm, "snd_pcm_hw_constraints_complete failed\n");
2667 		goto error;
2668 	}
2669 
2670 	*rsubstream = substream;
2671 	return 0;
2672 
2673  error:
2674 	snd_pcm_release_substream(substream);
2675 	return err;
2676 }
2677 EXPORT_SYMBOL(snd_pcm_open_substream);
2678 
2679 static int snd_pcm_open_file(struct file *file,
2680 			     struct snd_pcm *pcm,
2681 			     int stream)
2682 {
2683 	struct snd_pcm_file *pcm_file;
2684 	struct snd_pcm_substream *substream;
2685 	int err;
2686 
2687 	err = snd_pcm_open_substream(pcm, stream, file, &substream);
2688 	if (err < 0)
2689 		return err;
2690 
2691 	pcm_file = kzalloc(sizeof(*pcm_file), GFP_KERNEL);
2692 	if (pcm_file == NULL) {
2693 		snd_pcm_release_substream(substream);
2694 		return -ENOMEM;
2695 	}
2696 	pcm_file->substream = substream;
2697 	if (substream->ref_count == 1)
2698 		substream->pcm_release = pcm_release_private;
2699 	file->private_data = pcm_file;
2700 
2701 	return 0;
2702 }
2703 
2704 static int snd_pcm_playback_open(struct inode *inode, struct file *file)
2705 {
2706 	struct snd_pcm *pcm;
2707 	int err = nonseekable_open(inode, file);
2708 	if (err < 0)
2709 		return err;
2710 	pcm = snd_lookup_minor_data(iminor(inode),
2711 				    SNDRV_DEVICE_TYPE_PCM_PLAYBACK);
2712 	err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_PLAYBACK);
2713 	if (pcm)
2714 		snd_card_unref(pcm->card);
2715 	return err;
2716 }
2717 
2718 static int snd_pcm_capture_open(struct inode *inode, struct file *file)
2719 {
2720 	struct snd_pcm *pcm;
2721 	int err = nonseekable_open(inode, file);
2722 	if (err < 0)
2723 		return err;
2724 	pcm = snd_lookup_minor_data(iminor(inode),
2725 				    SNDRV_DEVICE_TYPE_PCM_CAPTURE);
2726 	err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_CAPTURE);
2727 	if (pcm)
2728 		snd_card_unref(pcm->card);
2729 	return err;
2730 }
2731 
2732 static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream)
2733 {
2734 	int err;
2735 	wait_queue_entry_t wait;
2736 
2737 	if (pcm == NULL) {
2738 		err = -ENODEV;
2739 		goto __error1;
2740 	}
2741 	err = snd_card_file_add(pcm->card, file);
2742 	if (err < 0)
2743 		goto __error1;
2744 	if (!try_module_get(pcm->card->module)) {
2745 		err = -EFAULT;
2746 		goto __error2;
2747 	}
2748 	init_waitqueue_entry(&wait, current);
2749 	add_wait_queue(&pcm->open_wait, &wait);
2750 	mutex_lock(&pcm->open_mutex);
2751 	while (1) {
2752 		err = snd_pcm_open_file(file, pcm, stream);
2753 		if (err >= 0)
2754 			break;
2755 		if (err == -EAGAIN) {
2756 			if (file->f_flags & O_NONBLOCK) {
2757 				err = -EBUSY;
2758 				break;
2759 			}
2760 		} else
2761 			break;
2762 		set_current_state(TASK_INTERRUPTIBLE);
2763 		mutex_unlock(&pcm->open_mutex);
2764 		schedule();
2765 		mutex_lock(&pcm->open_mutex);
2766 		if (pcm->card->shutdown) {
2767 			err = -ENODEV;
2768 			break;
2769 		}
2770 		if (signal_pending(current)) {
2771 			err = -ERESTARTSYS;
2772 			break;
2773 		}
2774 	}
2775 	remove_wait_queue(&pcm->open_wait, &wait);
2776 	mutex_unlock(&pcm->open_mutex);
2777 	if (err < 0)
2778 		goto __error;
2779 	return err;
2780 
2781       __error:
2782 	module_put(pcm->card->module);
2783       __error2:
2784       	snd_card_file_remove(pcm->card, file);
2785       __error1:
2786       	return err;
2787 }
2788 
2789 static int snd_pcm_release(struct inode *inode, struct file *file)
2790 {
2791 	struct snd_pcm *pcm;
2792 	struct snd_pcm_substream *substream;
2793 	struct snd_pcm_file *pcm_file;
2794 
2795 	pcm_file = file->private_data;
2796 	substream = pcm_file->substream;
2797 	if (snd_BUG_ON(!substream))
2798 		return -ENXIO;
2799 	pcm = substream->pcm;
2800 	mutex_lock(&pcm->open_mutex);
2801 	snd_pcm_release_substream(substream);
2802 	kfree(pcm_file);
2803 	mutex_unlock(&pcm->open_mutex);
2804 	wake_up(&pcm->open_wait);
2805 	module_put(pcm->card->module);
2806 	snd_card_file_remove(pcm->card, file);
2807 	return 0;
2808 }
2809 
2810 /* check and update PCM state; return 0 or a negative error
2811  * call this inside PCM lock
2812  */
2813 static int do_pcm_hwsync(struct snd_pcm_substream *substream)
2814 {
2815 	switch (substream->runtime->status->state) {
2816 	case SNDRV_PCM_STATE_DRAINING:
2817 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
2818 			return -EBADFD;
2819 		fallthrough;
2820 	case SNDRV_PCM_STATE_RUNNING:
2821 		return snd_pcm_update_hw_ptr(substream);
2822 	case SNDRV_PCM_STATE_PREPARED:
2823 	case SNDRV_PCM_STATE_PAUSED:
2824 		return 0;
2825 	case SNDRV_PCM_STATE_SUSPENDED:
2826 		return -ESTRPIPE;
2827 	case SNDRV_PCM_STATE_XRUN:
2828 		return -EPIPE;
2829 	default:
2830 		return -EBADFD;
2831 	}
2832 }
2833 
2834 /* increase the appl_ptr; returns the processed frames or a negative error */
2835 static snd_pcm_sframes_t forward_appl_ptr(struct snd_pcm_substream *substream,
2836 					  snd_pcm_uframes_t frames,
2837 					   snd_pcm_sframes_t avail)
2838 {
2839 	struct snd_pcm_runtime *runtime = substream->runtime;
2840 	snd_pcm_sframes_t appl_ptr;
2841 	int ret;
2842 
2843 	if (avail <= 0)
2844 		return 0;
2845 	if (frames > (snd_pcm_uframes_t)avail)
2846 		frames = avail;
2847 	appl_ptr = runtime->control->appl_ptr + frames;
2848 	if (appl_ptr >= (snd_pcm_sframes_t)runtime->boundary)
2849 		appl_ptr -= runtime->boundary;
2850 	ret = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2851 	return ret < 0 ? ret : frames;
2852 }
2853 
2854 /* decrease the appl_ptr; returns the processed frames or zero for error */
2855 static snd_pcm_sframes_t rewind_appl_ptr(struct snd_pcm_substream *substream,
2856 					 snd_pcm_uframes_t frames,
2857 					 snd_pcm_sframes_t avail)
2858 {
2859 	struct snd_pcm_runtime *runtime = substream->runtime;
2860 	snd_pcm_sframes_t appl_ptr;
2861 	int ret;
2862 
2863 	if (avail <= 0)
2864 		return 0;
2865 	if (frames > (snd_pcm_uframes_t)avail)
2866 		frames = avail;
2867 	appl_ptr = runtime->control->appl_ptr - frames;
2868 	if (appl_ptr < 0)
2869 		appl_ptr += runtime->boundary;
2870 	ret = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2871 	/* NOTE: we return zero for errors because PulseAudio gets depressed
2872 	 * upon receiving an error from rewind ioctl and stops processing
2873 	 * any longer.  Returning zero means that no rewind is done, so
2874 	 * it's not absolutely wrong to answer like that.
2875 	 */
2876 	return ret < 0 ? 0 : frames;
2877 }
2878 
2879 static snd_pcm_sframes_t snd_pcm_rewind(struct snd_pcm_substream *substream,
2880 					snd_pcm_uframes_t frames)
2881 {
2882 	snd_pcm_sframes_t ret;
2883 
2884 	if (frames == 0)
2885 		return 0;
2886 
2887 	snd_pcm_stream_lock_irq(substream);
2888 	ret = do_pcm_hwsync(substream);
2889 	if (!ret)
2890 		ret = rewind_appl_ptr(substream, frames,
2891 				      snd_pcm_hw_avail(substream));
2892 	snd_pcm_stream_unlock_irq(substream);
2893 	return ret;
2894 }
2895 
2896 static snd_pcm_sframes_t snd_pcm_forward(struct snd_pcm_substream *substream,
2897 					 snd_pcm_uframes_t frames)
2898 {
2899 	snd_pcm_sframes_t ret;
2900 
2901 	if (frames == 0)
2902 		return 0;
2903 
2904 	snd_pcm_stream_lock_irq(substream);
2905 	ret = do_pcm_hwsync(substream);
2906 	if (!ret)
2907 		ret = forward_appl_ptr(substream, frames,
2908 				       snd_pcm_avail(substream));
2909 	snd_pcm_stream_unlock_irq(substream);
2910 	return ret;
2911 }
2912 
2913 static int snd_pcm_hwsync(struct snd_pcm_substream *substream)
2914 {
2915 	int err;
2916 
2917 	snd_pcm_stream_lock_irq(substream);
2918 	err = do_pcm_hwsync(substream);
2919 	snd_pcm_stream_unlock_irq(substream);
2920 	return err;
2921 }
2922 
2923 static int snd_pcm_delay(struct snd_pcm_substream *substream,
2924 			 snd_pcm_sframes_t *delay)
2925 {
2926 	int err;
2927 	snd_pcm_sframes_t n = 0;
2928 
2929 	snd_pcm_stream_lock_irq(substream);
2930 	err = do_pcm_hwsync(substream);
2931 	if (!err)
2932 		n = snd_pcm_calc_delay(substream);
2933 	snd_pcm_stream_unlock_irq(substream);
2934 	if (!err)
2935 		*delay = n;
2936 	return err;
2937 }
2938 
2939 static int snd_pcm_sync_ptr(struct snd_pcm_substream *substream,
2940 			    struct snd_pcm_sync_ptr __user *_sync_ptr)
2941 {
2942 	struct snd_pcm_runtime *runtime = substream->runtime;
2943 	struct snd_pcm_sync_ptr sync_ptr;
2944 	volatile struct snd_pcm_mmap_status *status;
2945 	volatile struct snd_pcm_mmap_control *control;
2946 	int err;
2947 
2948 	memset(&sync_ptr, 0, sizeof(sync_ptr));
2949 	if (get_user(sync_ptr.flags, (unsigned __user *)&(_sync_ptr->flags)))
2950 		return -EFAULT;
2951 	if (copy_from_user(&sync_ptr.c.control, &(_sync_ptr->c.control), sizeof(struct snd_pcm_mmap_control)))
2952 		return -EFAULT;
2953 	status = runtime->status;
2954 	control = runtime->control;
2955 	if (sync_ptr.flags & SNDRV_PCM_SYNC_PTR_HWSYNC) {
2956 		err = snd_pcm_hwsync(substream);
2957 		if (err < 0)
2958 			return err;
2959 	}
2960 	snd_pcm_stream_lock_irq(substream);
2961 	if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_APPL)) {
2962 		err = pcm_lib_apply_appl_ptr(substream,
2963 					     sync_ptr.c.control.appl_ptr);
2964 		if (err < 0) {
2965 			snd_pcm_stream_unlock_irq(substream);
2966 			return err;
2967 		}
2968 	} else {
2969 		sync_ptr.c.control.appl_ptr = control->appl_ptr;
2970 	}
2971 	if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_AVAIL_MIN))
2972 		control->avail_min = sync_ptr.c.control.avail_min;
2973 	else
2974 		sync_ptr.c.control.avail_min = control->avail_min;
2975 	sync_ptr.s.status.state = status->state;
2976 	sync_ptr.s.status.hw_ptr = status->hw_ptr;
2977 	sync_ptr.s.status.tstamp = status->tstamp;
2978 	sync_ptr.s.status.suspended_state = status->suspended_state;
2979 	sync_ptr.s.status.audio_tstamp = status->audio_tstamp;
2980 	snd_pcm_stream_unlock_irq(substream);
2981 	if (copy_to_user(_sync_ptr, &sync_ptr, sizeof(sync_ptr)))
2982 		return -EFAULT;
2983 	return 0;
2984 }
2985 
2986 struct snd_pcm_mmap_status32 {
2987 	snd_pcm_state_t state;
2988 	s32 pad1;
2989 	u32 hw_ptr;
2990 	s32 tstamp_sec;
2991 	s32 tstamp_nsec;
2992 	snd_pcm_state_t suspended_state;
2993 	s32 audio_tstamp_sec;
2994 	s32 audio_tstamp_nsec;
2995 } __attribute__((packed));
2996 
2997 struct snd_pcm_mmap_control32 {
2998 	u32 appl_ptr;
2999 	u32 avail_min;
3000 };
3001 
3002 struct snd_pcm_sync_ptr32 {
3003 	u32 flags;
3004 	union {
3005 		struct snd_pcm_mmap_status32 status;
3006 		unsigned char reserved[64];
3007 	} s;
3008 	union {
3009 		struct snd_pcm_mmap_control32 control;
3010 		unsigned char reserved[64];
3011 	} c;
3012 } __attribute__((packed));
3013 
3014 /* recalcuate the boundary within 32bit */
3015 static snd_pcm_uframes_t recalculate_boundary(struct snd_pcm_runtime *runtime)
3016 {
3017 	snd_pcm_uframes_t boundary;
3018 
3019 	if (! runtime->buffer_size)
3020 		return 0;
3021 	boundary = runtime->buffer_size;
3022 	while (boundary * 2 <= 0x7fffffffUL - runtime->buffer_size)
3023 		boundary *= 2;
3024 	return boundary;
3025 }
3026 
3027 static int snd_pcm_ioctl_sync_ptr_compat(struct snd_pcm_substream *substream,
3028 					 struct snd_pcm_sync_ptr32 __user *src)
3029 {
3030 	struct snd_pcm_runtime *runtime = substream->runtime;
3031 	volatile struct snd_pcm_mmap_status *status;
3032 	volatile struct snd_pcm_mmap_control *control;
3033 	u32 sflags;
3034 	struct snd_pcm_mmap_control scontrol;
3035 	struct snd_pcm_mmap_status sstatus;
3036 	snd_pcm_uframes_t boundary;
3037 	int err;
3038 
3039 	if (snd_BUG_ON(!runtime))
3040 		return -EINVAL;
3041 
3042 	if (get_user(sflags, &src->flags) ||
3043 	    get_user(scontrol.appl_ptr, &src->c.control.appl_ptr) ||
3044 	    get_user(scontrol.avail_min, &src->c.control.avail_min))
3045 		return -EFAULT;
3046 	if (sflags & SNDRV_PCM_SYNC_PTR_HWSYNC) {
3047 		err = snd_pcm_hwsync(substream);
3048 		if (err < 0)
3049 			return err;
3050 	}
3051 	status = runtime->status;
3052 	control = runtime->control;
3053 	boundary = recalculate_boundary(runtime);
3054 	if (! boundary)
3055 		boundary = 0x7fffffff;
3056 	snd_pcm_stream_lock_irq(substream);
3057 	/* FIXME: we should consider the boundary for the sync from app */
3058 	if (!(sflags & SNDRV_PCM_SYNC_PTR_APPL))
3059 		control->appl_ptr = scontrol.appl_ptr;
3060 	else
3061 		scontrol.appl_ptr = control->appl_ptr % boundary;
3062 	if (!(sflags & SNDRV_PCM_SYNC_PTR_AVAIL_MIN))
3063 		control->avail_min = scontrol.avail_min;
3064 	else
3065 		scontrol.avail_min = control->avail_min;
3066 	sstatus.state = status->state;
3067 	sstatus.hw_ptr = status->hw_ptr % boundary;
3068 	sstatus.tstamp = status->tstamp;
3069 	sstatus.suspended_state = status->suspended_state;
3070 	sstatus.audio_tstamp = status->audio_tstamp;
3071 	snd_pcm_stream_unlock_irq(substream);
3072 	if (put_user(sstatus.state, &src->s.status.state) ||
3073 	    put_user(sstatus.hw_ptr, &src->s.status.hw_ptr) ||
3074 	    put_user(sstatus.tstamp.tv_sec, &src->s.status.tstamp_sec) ||
3075 	    put_user(sstatus.tstamp.tv_nsec, &src->s.status.tstamp_nsec) ||
3076 	    put_user(sstatus.suspended_state, &src->s.status.suspended_state) ||
3077 	    put_user(sstatus.audio_tstamp.tv_sec, &src->s.status.audio_tstamp_sec) ||
3078 	    put_user(sstatus.audio_tstamp.tv_nsec, &src->s.status.audio_tstamp_nsec) ||
3079 	    put_user(scontrol.appl_ptr, &src->c.control.appl_ptr) ||
3080 	    put_user(scontrol.avail_min, &src->c.control.avail_min))
3081 		return -EFAULT;
3082 
3083 	return 0;
3084 }
3085 #define __SNDRV_PCM_IOCTL_SYNC_PTR32 _IOWR('A', 0x23, struct snd_pcm_sync_ptr32)
3086 
3087 static int snd_pcm_tstamp(struct snd_pcm_substream *substream, int __user *_arg)
3088 {
3089 	struct snd_pcm_runtime *runtime = substream->runtime;
3090 	int arg;
3091 
3092 	if (get_user(arg, _arg))
3093 		return -EFAULT;
3094 	if (arg < 0 || arg > SNDRV_PCM_TSTAMP_TYPE_LAST)
3095 		return -EINVAL;
3096 	runtime->tstamp_type = arg;
3097 	return 0;
3098 }
3099 
3100 static int snd_pcm_xferi_frames_ioctl(struct snd_pcm_substream *substream,
3101 				      struct snd_xferi __user *_xferi)
3102 {
3103 	struct snd_xferi xferi;
3104 	struct snd_pcm_runtime *runtime = substream->runtime;
3105 	snd_pcm_sframes_t result;
3106 
3107 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3108 		return -EBADFD;
3109 	if (put_user(0, &_xferi->result))
3110 		return -EFAULT;
3111 	if (copy_from_user(&xferi, _xferi, sizeof(xferi)))
3112 		return -EFAULT;
3113 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
3114 		result = snd_pcm_lib_write(substream, xferi.buf, xferi.frames);
3115 	else
3116 		result = snd_pcm_lib_read(substream, xferi.buf, xferi.frames);
3117 	if (put_user(result, &_xferi->result))
3118 		return -EFAULT;
3119 	return result < 0 ? result : 0;
3120 }
3121 
3122 static int snd_pcm_xfern_frames_ioctl(struct snd_pcm_substream *substream,
3123 				      struct snd_xfern __user *_xfern)
3124 {
3125 	struct snd_xfern xfern;
3126 	struct snd_pcm_runtime *runtime = substream->runtime;
3127 	void *bufs;
3128 	snd_pcm_sframes_t result;
3129 
3130 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3131 		return -EBADFD;
3132 	if (runtime->channels > 128)
3133 		return -EINVAL;
3134 	if (put_user(0, &_xfern->result))
3135 		return -EFAULT;
3136 	if (copy_from_user(&xfern, _xfern, sizeof(xfern)))
3137 		return -EFAULT;
3138 
3139 	bufs = memdup_user(xfern.bufs, sizeof(void *) * runtime->channels);
3140 	if (IS_ERR(bufs))
3141 		return PTR_ERR(bufs);
3142 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
3143 		result = snd_pcm_lib_writev(substream, bufs, xfern.frames);
3144 	else
3145 		result = snd_pcm_lib_readv(substream, bufs, xfern.frames);
3146 	kfree(bufs);
3147 	if (put_user(result, &_xfern->result))
3148 		return -EFAULT;
3149 	return result < 0 ? result : 0;
3150 }
3151 
3152 static int snd_pcm_rewind_ioctl(struct snd_pcm_substream *substream,
3153 				snd_pcm_uframes_t __user *_frames)
3154 {
3155 	snd_pcm_uframes_t frames;
3156 	snd_pcm_sframes_t result;
3157 
3158 	if (get_user(frames, _frames))
3159 		return -EFAULT;
3160 	if (put_user(0, _frames))
3161 		return -EFAULT;
3162 	result = snd_pcm_rewind(substream, frames);
3163 	if (put_user(result, _frames))
3164 		return -EFAULT;
3165 	return result < 0 ? result : 0;
3166 }
3167 
3168 static int snd_pcm_forward_ioctl(struct snd_pcm_substream *substream,
3169 				 snd_pcm_uframes_t __user *_frames)
3170 {
3171 	snd_pcm_uframes_t frames;
3172 	snd_pcm_sframes_t result;
3173 
3174 	if (get_user(frames, _frames))
3175 		return -EFAULT;
3176 	if (put_user(0, _frames))
3177 		return -EFAULT;
3178 	result = snd_pcm_forward(substream, frames);
3179 	if (put_user(result, _frames))
3180 		return -EFAULT;
3181 	return result < 0 ? result : 0;
3182 }
3183 
3184 static int snd_pcm_common_ioctl(struct file *file,
3185 				 struct snd_pcm_substream *substream,
3186 				 unsigned int cmd, void __user *arg)
3187 {
3188 	struct snd_pcm_file *pcm_file = file->private_data;
3189 	int res;
3190 
3191 	if (PCM_RUNTIME_CHECK(substream))
3192 		return -ENXIO;
3193 
3194 	res = snd_power_wait(substream->pcm->card, SNDRV_CTL_POWER_D0);
3195 	if (res < 0)
3196 		return res;
3197 
3198 	switch (cmd) {
3199 	case SNDRV_PCM_IOCTL_PVERSION:
3200 		return put_user(SNDRV_PCM_VERSION, (int __user *)arg) ? -EFAULT : 0;
3201 	case SNDRV_PCM_IOCTL_INFO:
3202 		return snd_pcm_info_user(substream, arg);
3203 	case SNDRV_PCM_IOCTL_TSTAMP:	/* just for compatibility */
3204 		return 0;
3205 	case SNDRV_PCM_IOCTL_TTSTAMP:
3206 		return snd_pcm_tstamp(substream, arg);
3207 	case SNDRV_PCM_IOCTL_USER_PVERSION:
3208 		if (get_user(pcm_file->user_pversion,
3209 			     (unsigned int __user *)arg))
3210 			return -EFAULT;
3211 		return 0;
3212 	case SNDRV_PCM_IOCTL_HW_REFINE:
3213 		return snd_pcm_hw_refine_user(substream, arg);
3214 	case SNDRV_PCM_IOCTL_HW_PARAMS:
3215 		return snd_pcm_hw_params_user(substream, arg);
3216 	case SNDRV_PCM_IOCTL_HW_FREE:
3217 		return snd_pcm_hw_free(substream);
3218 	case SNDRV_PCM_IOCTL_SW_PARAMS:
3219 		return snd_pcm_sw_params_user(substream, arg);
3220 	case SNDRV_PCM_IOCTL_STATUS32:
3221 		return snd_pcm_status_user32(substream, arg, false);
3222 	case SNDRV_PCM_IOCTL_STATUS_EXT32:
3223 		return snd_pcm_status_user32(substream, arg, true);
3224 	case SNDRV_PCM_IOCTL_STATUS64:
3225 		return snd_pcm_status_user64(substream, arg, false);
3226 	case SNDRV_PCM_IOCTL_STATUS_EXT64:
3227 		return snd_pcm_status_user64(substream, arg, true);
3228 	case SNDRV_PCM_IOCTL_CHANNEL_INFO:
3229 		return snd_pcm_channel_info_user(substream, arg);
3230 	case SNDRV_PCM_IOCTL_PREPARE:
3231 		return snd_pcm_prepare(substream, file);
3232 	case SNDRV_PCM_IOCTL_RESET:
3233 		return snd_pcm_reset(substream);
3234 	case SNDRV_PCM_IOCTL_START:
3235 		return snd_pcm_start_lock_irq(substream);
3236 	case SNDRV_PCM_IOCTL_LINK:
3237 		return snd_pcm_link(substream, (int)(unsigned long) arg);
3238 	case SNDRV_PCM_IOCTL_UNLINK:
3239 		return snd_pcm_unlink(substream);
3240 	case SNDRV_PCM_IOCTL_RESUME:
3241 		return snd_pcm_resume(substream);
3242 	case SNDRV_PCM_IOCTL_XRUN:
3243 		return snd_pcm_xrun(substream);
3244 	case SNDRV_PCM_IOCTL_HWSYNC:
3245 		return snd_pcm_hwsync(substream);
3246 	case SNDRV_PCM_IOCTL_DELAY:
3247 	{
3248 		snd_pcm_sframes_t delay;
3249 		snd_pcm_sframes_t __user *res = arg;
3250 		int err;
3251 
3252 		err = snd_pcm_delay(substream, &delay);
3253 		if (err)
3254 			return err;
3255 		if (put_user(delay, res))
3256 			return -EFAULT;
3257 		return 0;
3258 	}
3259 	case __SNDRV_PCM_IOCTL_SYNC_PTR32:
3260 		return snd_pcm_ioctl_sync_ptr_compat(substream, arg);
3261 	case __SNDRV_PCM_IOCTL_SYNC_PTR64:
3262 		return snd_pcm_sync_ptr(substream, arg);
3263 #ifdef CONFIG_SND_SUPPORT_OLD_API
3264 	case SNDRV_PCM_IOCTL_HW_REFINE_OLD:
3265 		return snd_pcm_hw_refine_old_user(substream, arg);
3266 	case SNDRV_PCM_IOCTL_HW_PARAMS_OLD:
3267 		return snd_pcm_hw_params_old_user(substream, arg);
3268 #endif
3269 	case SNDRV_PCM_IOCTL_DRAIN:
3270 		return snd_pcm_drain(substream, file);
3271 	case SNDRV_PCM_IOCTL_DROP:
3272 		return snd_pcm_drop(substream);
3273 	case SNDRV_PCM_IOCTL_PAUSE:
3274 		return snd_pcm_pause_lock_irq(substream, (unsigned long)arg);
3275 	case SNDRV_PCM_IOCTL_WRITEI_FRAMES:
3276 	case SNDRV_PCM_IOCTL_READI_FRAMES:
3277 		return snd_pcm_xferi_frames_ioctl(substream, arg);
3278 	case SNDRV_PCM_IOCTL_WRITEN_FRAMES:
3279 	case SNDRV_PCM_IOCTL_READN_FRAMES:
3280 		return snd_pcm_xfern_frames_ioctl(substream, arg);
3281 	case SNDRV_PCM_IOCTL_REWIND:
3282 		return snd_pcm_rewind_ioctl(substream, arg);
3283 	case SNDRV_PCM_IOCTL_FORWARD:
3284 		return snd_pcm_forward_ioctl(substream, arg);
3285 	}
3286 	pcm_dbg(substream->pcm, "unknown ioctl = 0x%x\n", cmd);
3287 	return -ENOTTY;
3288 }
3289 
3290 static long snd_pcm_ioctl(struct file *file, unsigned int cmd,
3291 			  unsigned long arg)
3292 {
3293 	struct snd_pcm_file *pcm_file;
3294 
3295 	pcm_file = file->private_data;
3296 
3297 	if (((cmd >> 8) & 0xff) != 'A')
3298 		return -ENOTTY;
3299 
3300 	return snd_pcm_common_ioctl(file, pcm_file->substream, cmd,
3301 				     (void __user *)arg);
3302 }
3303 
3304 /**
3305  * snd_pcm_kernel_ioctl - Execute PCM ioctl in the kernel-space
3306  * @substream: PCM substream
3307  * @cmd: IOCTL cmd
3308  * @arg: IOCTL argument
3309  *
3310  * The function is provided primarily for OSS layer and USB gadget drivers,
3311  * and it allows only the limited set of ioctls (hw_params, sw_params,
3312  * prepare, start, drain, drop, forward).
3313  */
3314 int snd_pcm_kernel_ioctl(struct snd_pcm_substream *substream,
3315 			 unsigned int cmd, void *arg)
3316 {
3317 	snd_pcm_uframes_t *frames = arg;
3318 	snd_pcm_sframes_t result;
3319 
3320 	switch (cmd) {
3321 	case SNDRV_PCM_IOCTL_FORWARD:
3322 	{
3323 		/* provided only for OSS; capture-only and no value returned */
3324 		if (substream->stream != SNDRV_PCM_STREAM_CAPTURE)
3325 			return -EINVAL;
3326 		result = snd_pcm_forward(substream, *frames);
3327 		return result < 0 ? result : 0;
3328 	}
3329 	case SNDRV_PCM_IOCTL_HW_PARAMS:
3330 		return snd_pcm_hw_params(substream, arg);
3331 	case SNDRV_PCM_IOCTL_SW_PARAMS:
3332 		return snd_pcm_sw_params(substream, arg);
3333 	case SNDRV_PCM_IOCTL_PREPARE:
3334 		return snd_pcm_prepare(substream, NULL);
3335 	case SNDRV_PCM_IOCTL_START:
3336 		return snd_pcm_start_lock_irq(substream);
3337 	case SNDRV_PCM_IOCTL_DRAIN:
3338 		return snd_pcm_drain(substream, NULL);
3339 	case SNDRV_PCM_IOCTL_DROP:
3340 		return snd_pcm_drop(substream);
3341 	case SNDRV_PCM_IOCTL_DELAY:
3342 		return snd_pcm_delay(substream, frames);
3343 	default:
3344 		return -EINVAL;
3345 	}
3346 }
3347 EXPORT_SYMBOL(snd_pcm_kernel_ioctl);
3348 
3349 static ssize_t snd_pcm_read(struct file *file, char __user *buf, size_t count,
3350 			    loff_t * offset)
3351 {
3352 	struct snd_pcm_file *pcm_file;
3353 	struct snd_pcm_substream *substream;
3354 	struct snd_pcm_runtime *runtime;
3355 	snd_pcm_sframes_t result;
3356 
3357 	pcm_file = file->private_data;
3358 	substream = pcm_file->substream;
3359 	if (PCM_RUNTIME_CHECK(substream))
3360 		return -ENXIO;
3361 	runtime = substream->runtime;
3362 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3363 		return -EBADFD;
3364 	if (!frame_aligned(runtime, count))
3365 		return -EINVAL;
3366 	count = bytes_to_frames(runtime, count);
3367 	result = snd_pcm_lib_read(substream, buf, count);
3368 	if (result > 0)
3369 		result = frames_to_bytes(runtime, result);
3370 	return result;
3371 }
3372 
3373 static ssize_t snd_pcm_write(struct file *file, const char __user *buf,
3374 			     size_t count, loff_t * offset)
3375 {
3376 	struct snd_pcm_file *pcm_file;
3377 	struct snd_pcm_substream *substream;
3378 	struct snd_pcm_runtime *runtime;
3379 	snd_pcm_sframes_t result;
3380 
3381 	pcm_file = file->private_data;
3382 	substream = pcm_file->substream;
3383 	if (PCM_RUNTIME_CHECK(substream))
3384 		return -ENXIO;
3385 	runtime = substream->runtime;
3386 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3387 		return -EBADFD;
3388 	if (!frame_aligned(runtime, count))
3389 		return -EINVAL;
3390 	count = bytes_to_frames(runtime, count);
3391 	result = snd_pcm_lib_write(substream, buf, count);
3392 	if (result > 0)
3393 		result = frames_to_bytes(runtime, result);
3394 	return result;
3395 }
3396 
3397 static ssize_t snd_pcm_readv(struct kiocb *iocb, struct iov_iter *to)
3398 {
3399 	struct snd_pcm_file *pcm_file;
3400 	struct snd_pcm_substream *substream;
3401 	struct snd_pcm_runtime *runtime;
3402 	snd_pcm_sframes_t result;
3403 	unsigned long i;
3404 	void __user **bufs;
3405 	snd_pcm_uframes_t frames;
3406 
3407 	pcm_file = iocb->ki_filp->private_data;
3408 	substream = pcm_file->substream;
3409 	if (PCM_RUNTIME_CHECK(substream))
3410 		return -ENXIO;
3411 	runtime = substream->runtime;
3412 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3413 		return -EBADFD;
3414 	if (!iter_is_iovec(to))
3415 		return -EINVAL;
3416 	if (to->nr_segs > 1024 || to->nr_segs != runtime->channels)
3417 		return -EINVAL;
3418 	if (!frame_aligned(runtime, to->iov->iov_len))
3419 		return -EINVAL;
3420 	frames = bytes_to_samples(runtime, to->iov->iov_len);
3421 	bufs = kmalloc_array(to->nr_segs, sizeof(void *), GFP_KERNEL);
3422 	if (bufs == NULL)
3423 		return -ENOMEM;
3424 	for (i = 0; i < to->nr_segs; ++i)
3425 		bufs[i] = to->iov[i].iov_base;
3426 	result = snd_pcm_lib_readv(substream, bufs, frames);
3427 	if (result > 0)
3428 		result = frames_to_bytes(runtime, result);
3429 	kfree(bufs);
3430 	return result;
3431 }
3432 
3433 static ssize_t snd_pcm_writev(struct kiocb *iocb, struct iov_iter *from)
3434 {
3435 	struct snd_pcm_file *pcm_file;
3436 	struct snd_pcm_substream *substream;
3437 	struct snd_pcm_runtime *runtime;
3438 	snd_pcm_sframes_t result;
3439 	unsigned long i;
3440 	void __user **bufs;
3441 	snd_pcm_uframes_t frames;
3442 
3443 	pcm_file = iocb->ki_filp->private_data;
3444 	substream = pcm_file->substream;
3445 	if (PCM_RUNTIME_CHECK(substream))
3446 		return -ENXIO;
3447 	runtime = substream->runtime;
3448 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3449 		return -EBADFD;
3450 	if (!iter_is_iovec(from))
3451 		return -EINVAL;
3452 	if (from->nr_segs > 128 || from->nr_segs != runtime->channels ||
3453 	    !frame_aligned(runtime, from->iov->iov_len))
3454 		return -EINVAL;
3455 	frames = bytes_to_samples(runtime, from->iov->iov_len);
3456 	bufs = kmalloc_array(from->nr_segs, sizeof(void *), GFP_KERNEL);
3457 	if (bufs == NULL)
3458 		return -ENOMEM;
3459 	for (i = 0; i < from->nr_segs; ++i)
3460 		bufs[i] = from->iov[i].iov_base;
3461 	result = snd_pcm_lib_writev(substream, bufs, frames);
3462 	if (result > 0)
3463 		result = frames_to_bytes(runtime, result);
3464 	kfree(bufs);
3465 	return result;
3466 }
3467 
3468 static __poll_t snd_pcm_poll(struct file *file, poll_table *wait)
3469 {
3470 	struct snd_pcm_file *pcm_file;
3471 	struct snd_pcm_substream *substream;
3472 	struct snd_pcm_runtime *runtime;
3473 	__poll_t mask, ok;
3474 	snd_pcm_uframes_t avail;
3475 
3476 	pcm_file = file->private_data;
3477 
3478 	substream = pcm_file->substream;
3479 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
3480 		ok = EPOLLOUT | EPOLLWRNORM;
3481 	else
3482 		ok = EPOLLIN | EPOLLRDNORM;
3483 	if (PCM_RUNTIME_CHECK(substream))
3484 		return ok | EPOLLERR;
3485 
3486 	runtime = substream->runtime;
3487 	poll_wait(file, &runtime->sleep, wait);
3488 
3489 	mask = 0;
3490 	snd_pcm_stream_lock_irq(substream);
3491 	avail = snd_pcm_avail(substream);
3492 	switch (runtime->status->state) {
3493 	case SNDRV_PCM_STATE_RUNNING:
3494 	case SNDRV_PCM_STATE_PREPARED:
3495 	case SNDRV_PCM_STATE_PAUSED:
3496 		if (avail >= runtime->control->avail_min)
3497 			mask = ok;
3498 		break;
3499 	case SNDRV_PCM_STATE_DRAINING:
3500 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
3501 			mask = ok;
3502 			if (!avail)
3503 				mask |= EPOLLERR;
3504 		}
3505 		break;
3506 	default:
3507 		mask = ok | EPOLLERR;
3508 		break;
3509 	}
3510 	snd_pcm_stream_unlock_irq(substream);
3511 	return mask;
3512 }
3513 
3514 /*
3515  * mmap support
3516  */
3517 
3518 /*
3519  * Only on coherent architectures, we can mmap the status and the control records
3520  * for effcient data transfer.  On others, we have to use HWSYNC ioctl...
3521  */
3522 #if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_ALPHA)
3523 /*
3524  * mmap status record
3525  */
3526 static vm_fault_t snd_pcm_mmap_status_fault(struct vm_fault *vmf)
3527 {
3528 	struct snd_pcm_substream *substream = vmf->vma->vm_private_data;
3529 	struct snd_pcm_runtime *runtime;
3530 
3531 	if (substream == NULL)
3532 		return VM_FAULT_SIGBUS;
3533 	runtime = substream->runtime;
3534 	vmf->page = virt_to_page(runtime->status);
3535 	get_page(vmf->page);
3536 	return 0;
3537 }
3538 
3539 static const struct vm_operations_struct snd_pcm_vm_ops_status =
3540 {
3541 	.fault =	snd_pcm_mmap_status_fault,
3542 };
3543 
3544 static int snd_pcm_mmap_status(struct snd_pcm_substream *substream, struct file *file,
3545 			       struct vm_area_struct *area)
3546 {
3547 	long size;
3548 	if (!(area->vm_flags & VM_READ))
3549 		return -EINVAL;
3550 	size = area->vm_end - area->vm_start;
3551 	if (size != PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)))
3552 		return -EINVAL;
3553 	area->vm_ops = &snd_pcm_vm_ops_status;
3554 	area->vm_private_data = substream;
3555 	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
3556 	return 0;
3557 }
3558 
3559 /*
3560  * mmap control record
3561  */
3562 static vm_fault_t snd_pcm_mmap_control_fault(struct vm_fault *vmf)
3563 {
3564 	struct snd_pcm_substream *substream = vmf->vma->vm_private_data;
3565 	struct snd_pcm_runtime *runtime;
3566 
3567 	if (substream == NULL)
3568 		return VM_FAULT_SIGBUS;
3569 	runtime = substream->runtime;
3570 	vmf->page = virt_to_page(runtime->control);
3571 	get_page(vmf->page);
3572 	return 0;
3573 }
3574 
3575 static const struct vm_operations_struct snd_pcm_vm_ops_control =
3576 {
3577 	.fault =	snd_pcm_mmap_control_fault,
3578 };
3579 
3580 static int snd_pcm_mmap_control(struct snd_pcm_substream *substream, struct file *file,
3581 				struct vm_area_struct *area)
3582 {
3583 	long size;
3584 	if (!(area->vm_flags & VM_READ))
3585 		return -EINVAL;
3586 	size = area->vm_end - area->vm_start;
3587 	if (size != PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)))
3588 		return -EINVAL;
3589 	area->vm_ops = &snd_pcm_vm_ops_control;
3590 	area->vm_private_data = substream;
3591 	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
3592 	return 0;
3593 }
3594 
3595 static bool pcm_status_mmap_allowed(struct snd_pcm_file *pcm_file)
3596 {
3597 	/* See pcm_control_mmap_allowed() below.
3598 	 * Since older alsa-lib requires both status and control mmaps to be
3599 	 * coupled, we have to disable the status mmap for old alsa-lib, too.
3600 	 */
3601 	if (pcm_file->user_pversion < SNDRV_PROTOCOL_VERSION(2, 0, 14) &&
3602 	    (pcm_file->substream->runtime->hw.info & SNDRV_PCM_INFO_SYNC_APPLPTR))
3603 		return false;
3604 	return true;
3605 }
3606 
3607 static bool pcm_control_mmap_allowed(struct snd_pcm_file *pcm_file)
3608 {
3609 	if (pcm_file->no_compat_mmap)
3610 		return false;
3611 	/* Disallow the control mmap when SYNC_APPLPTR flag is set;
3612 	 * it enforces the user-space to fall back to snd_pcm_sync_ptr(),
3613 	 * thus it effectively assures the manual update of appl_ptr.
3614 	 */
3615 	if (pcm_file->substream->runtime->hw.info & SNDRV_PCM_INFO_SYNC_APPLPTR)
3616 		return false;
3617 	return true;
3618 }
3619 
3620 #else /* ! coherent mmap */
3621 /*
3622  * don't support mmap for status and control records.
3623  */
3624 #define pcm_status_mmap_allowed(pcm_file)	false
3625 #define pcm_control_mmap_allowed(pcm_file)	false
3626 
3627 static int snd_pcm_mmap_status(struct snd_pcm_substream *substream, struct file *file,
3628 			       struct vm_area_struct *area)
3629 {
3630 	return -ENXIO;
3631 }
3632 static int snd_pcm_mmap_control(struct snd_pcm_substream *substream, struct file *file,
3633 				struct vm_area_struct *area)
3634 {
3635 	return -ENXIO;
3636 }
3637 #endif /* coherent mmap */
3638 
3639 static inline struct page *
3640 snd_pcm_default_page_ops(struct snd_pcm_substream *substream, unsigned long ofs)
3641 {
3642 	void *vaddr = substream->runtime->dma_area + ofs;
3643 
3644 	switch (substream->dma_buffer.dev.type) {
3645 #ifdef CONFIG_SND_DMA_SGBUF
3646 	case SNDRV_DMA_TYPE_DEV_SG:
3647 	case SNDRV_DMA_TYPE_DEV_UC_SG:
3648 		return snd_pcm_sgbuf_ops_page(substream, ofs);
3649 #endif /* CONFIG_SND_DMA_SGBUF */
3650 	case SNDRV_DMA_TYPE_VMALLOC:
3651 		return vmalloc_to_page(vaddr);
3652 	default:
3653 		return virt_to_page(vaddr);
3654 	}
3655 }
3656 
3657 /*
3658  * fault callback for mmapping a RAM page
3659  */
3660 static vm_fault_t snd_pcm_mmap_data_fault(struct vm_fault *vmf)
3661 {
3662 	struct snd_pcm_substream *substream = vmf->vma->vm_private_data;
3663 	struct snd_pcm_runtime *runtime;
3664 	unsigned long offset;
3665 	struct page * page;
3666 	size_t dma_bytes;
3667 
3668 	if (substream == NULL)
3669 		return VM_FAULT_SIGBUS;
3670 	runtime = substream->runtime;
3671 	offset = vmf->pgoff << PAGE_SHIFT;
3672 	dma_bytes = PAGE_ALIGN(runtime->dma_bytes);
3673 	if (offset > dma_bytes - PAGE_SIZE)
3674 		return VM_FAULT_SIGBUS;
3675 	if (substream->ops->page)
3676 		page = substream->ops->page(substream, offset);
3677 	else
3678 		page = snd_pcm_default_page_ops(substream, offset);
3679 	if (!page)
3680 		return VM_FAULT_SIGBUS;
3681 	get_page(page);
3682 	vmf->page = page;
3683 	return 0;
3684 }
3685 
3686 static const struct vm_operations_struct snd_pcm_vm_ops_data = {
3687 	.open =		snd_pcm_mmap_data_open,
3688 	.close =	snd_pcm_mmap_data_close,
3689 };
3690 
3691 static const struct vm_operations_struct snd_pcm_vm_ops_data_fault = {
3692 	.open =		snd_pcm_mmap_data_open,
3693 	.close =	snd_pcm_mmap_data_close,
3694 	.fault =	snd_pcm_mmap_data_fault,
3695 };
3696 
3697 /*
3698  * mmap the DMA buffer on RAM
3699  */
3700 
3701 /**
3702  * snd_pcm_lib_default_mmap - Default PCM data mmap function
3703  * @substream: PCM substream
3704  * @area: VMA
3705  *
3706  * This is the default mmap handler for PCM data.  When mmap pcm_ops is NULL,
3707  * this function is invoked implicitly.
3708  */
3709 int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
3710 			     struct vm_area_struct *area)
3711 {
3712 	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
3713 #ifdef CONFIG_GENERIC_ALLOCATOR
3714 	if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV_IRAM) {
3715 		area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
3716 		return remap_pfn_range(area, area->vm_start,
3717 				substream->dma_buffer.addr >> PAGE_SHIFT,
3718 				area->vm_end - area->vm_start, area->vm_page_prot);
3719 	}
3720 #endif /* CONFIG_GENERIC_ALLOCATOR */
3721 	if (IS_ENABLED(CONFIG_HAS_DMA) && !substream->ops->page &&
3722 	    (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV ||
3723 	     substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV_UC))
3724 		return dma_mmap_coherent(substream->dma_buffer.dev.dev,
3725 					 area,
3726 					 substream->runtime->dma_area,
3727 					 substream->runtime->dma_addr,
3728 					 substream->runtime->dma_bytes);
3729 	/* mmap with fault handler */
3730 	area->vm_ops = &snd_pcm_vm_ops_data_fault;
3731 	return 0;
3732 }
3733 EXPORT_SYMBOL_GPL(snd_pcm_lib_default_mmap);
3734 
3735 /*
3736  * mmap the DMA buffer on I/O memory area
3737  */
3738 #if SNDRV_PCM_INFO_MMAP_IOMEM
3739 /**
3740  * snd_pcm_lib_mmap_iomem - Default PCM data mmap function for I/O mem
3741  * @substream: PCM substream
3742  * @area: VMA
3743  *
3744  * When your hardware uses the iomapped pages as the hardware buffer and
3745  * wants to mmap it, pass this function as mmap pcm_ops.  Note that this
3746  * is supposed to work only on limited architectures.
3747  */
3748 int snd_pcm_lib_mmap_iomem(struct snd_pcm_substream *substream,
3749 			   struct vm_area_struct *area)
3750 {
3751 	struct snd_pcm_runtime *runtime = substream->runtime;
3752 
3753 	area->vm_page_prot = pgprot_noncached(area->vm_page_prot);
3754 	return vm_iomap_memory(area, runtime->dma_addr, runtime->dma_bytes);
3755 }
3756 EXPORT_SYMBOL(snd_pcm_lib_mmap_iomem);
3757 #endif /* SNDRV_PCM_INFO_MMAP */
3758 
3759 /*
3760  * mmap DMA buffer
3761  */
3762 int snd_pcm_mmap_data(struct snd_pcm_substream *substream, struct file *file,
3763 		      struct vm_area_struct *area)
3764 {
3765 	struct snd_pcm_runtime *runtime;
3766 	long size;
3767 	unsigned long offset;
3768 	size_t dma_bytes;
3769 	int err;
3770 
3771 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
3772 		if (!(area->vm_flags & (VM_WRITE|VM_READ)))
3773 			return -EINVAL;
3774 	} else {
3775 		if (!(area->vm_flags & VM_READ))
3776 			return -EINVAL;
3777 	}
3778 	runtime = substream->runtime;
3779 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3780 		return -EBADFD;
3781 	if (!(runtime->info & SNDRV_PCM_INFO_MMAP))
3782 		return -ENXIO;
3783 	if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
3784 	    runtime->access == SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
3785 		return -EINVAL;
3786 	size = area->vm_end - area->vm_start;
3787 	offset = area->vm_pgoff << PAGE_SHIFT;
3788 	dma_bytes = PAGE_ALIGN(runtime->dma_bytes);
3789 	if ((size_t)size > dma_bytes)
3790 		return -EINVAL;
3791 	if (offset > dma_bytes - size)
3792 		return -EINVAL;
3793 
3794 	area->vm_ops = &snd_pcm_vm_ops_data;
3795 	area->vm_private_data = substream;
3796 	if (substream->ops->mmap)
3797 		err = substream->ops->mmap(substream, area);
3798 	else
3799 		err = snd_pcm_lib_default_mmap(substream, area);
3800 	if (!err)
3801 		atomic_inc(&substream->mmap_count);
3802 	return err;
3803 }
3804 EXPORT_SYMBOL(snd_pcm_mmap_data);
3805 
3806 static int snd_pcm_mmap(struct file *file, struct vm_area_struct *area)
3807 {
3808 	struct snd_pcm_file * pcm_file;
3809 	struct snd_pcm_substream *substream;
3810 	unsigned long offset;
3811 
3812 	pcm_file = file->private_data;
3813 	substream = pcm_file->substream;
3814 	if (PCM_RUNTIME_CHECK(substream))
3815 		return -ENXIO;
3816 
3817 	offset = area->vm_pgoff << PAGE_SHIFT;
3818 	switch (offset) {
3819 	case SNDRV_PCM_MMAP_OFFSET_STATUS_OLD:
3820 		if (pcm_file->no_compat_mmap || !IS_ENABLED(CONFIG_64BIT))
3821 			return -ENXIO;
3822 		fallthrough;
3823 	case SNDRV_PCM_MMAP_OFFSET_STATUS_NEW:
3824 		if (!pcm_status_mmap_allowed(pcm_file))
3825 			return -ENXIO;
3826 		return snd_pcm_mmap_status(substream, file, area);
3827 	case SNDRV_PCM_MMAP_OFFSET_CONTROL_OLD:
3828 		if (pcm_file->no_compat_mmap || !IS_ENABLED(CONFIG_64BIT))
3829 			return -ENXIO;
3830 		fallthrough;
3831 	case SNDRV_PCM_MMAP_OFFSET_CONTROL_NEW:
3832 		if (!pcm_control_mmap_allowed(pcm_file))
3833 			return -ENXIO;
3834 		return snd_pcm_mmap_control(substream, file, area);
3835 	default:
3836 		return snd_pcm_mmap_data(substream, file, area);
3837 	}
3838 	return 0;
3839 }
3840 
3841 static int snd_pcm_fasync(int fd, struct file * file, int on)
3842 {
3843 	struct snd_pcm_file * pcm_file;
3844 	struct snd_pcm_substream *substream;
3845 	struct snd_pcm_runtime *runtime;
3846 
3847 	pcm_file = file->private_data;
3848 	substream = pcm_file->substream;
3849 	if (PCM_RUNTIME_CHECK(substream))
3850 		return -ENXIO;
3851 	runtime = substream->runtime;
3852 	return fasync_helper(fd, file, on, &runtime->fasync);
3853 }
3854 
3855 /*
3856  * ioctl32 compat
3857  */
3858 #ifdef CONFIG_COMPAT
3859 #include "pcm_compat.c"
3860 #else
3861 #define snd_pcm_ioctl_compat	NULL
3862 #endif
3863 
3864 /*
3865  *  To be removed helpers to keep binary compatibility
3866  */
3867 
3868 #ifdef CONFIG_SND_SUPPORT_OLD_API
3869 #define __OLD_TO_NEW_MASK(x) ((x&7)|((x&0x07fffff8)<<5))
3870 #define __NEW_TO_OLD_MASK(x) ((x&7)|((x&0xffffff00)>>5))
3871 
3872 static void snd_pcm_hw_convert_from_old_params(struct snd_pcm_hw_params *params,
3873 					       struct snd_pcm_hw_params_old *oparams)
3874 {
3875 	unsigned int i;
3876 
3877 	memset(params, 0, sizeof(*params));
3878 	params->flags = oparams->flags;
3879 	for (i = 0; i < ARRAY_SIZE(oparams->masks); i++)
3880 		params->masks[i].bits[0] = oparams->masks[i];
3881 	memcpy(params->intervals, oparams->intervals, sizeof(oparams->intervals));
3882 	params->rmask = __OLD_TO_NEW_MASK(oparams->rmask);
3883 	params->cmask = __OLD_TO_NEW_MASK(oparams->cmask);
3884 	params->info = oparams->info;
3885 	params->msbits = oparams->msbits;
3886 	params->rate_num = oparams->rate_num;
3887 	params->rate_den = oparams->rate_den;
3888 	params->fifo_size = oparams->fifo_size;
3889 }
3890 
3891 static void snd_pcm_hw_convert_to_old_params(struct snd_pcm_hw_params_old *oparams,
3892 					     struct snd_pcm_hw_params *params)
3893 {
3894 	unsigned int i;
3895 
3896 	memset(oparams, 0, sizeof(*oparams));
3897 	oparams->flags = params->flags;
3898 	for (i = 0; i < ARRAY_SIZE(oparams->masks); i++)
3899 		oparams->masks[i] = params->masks[i].bits[0];
3900 	memcpy(oparams->intervals, params->intervals, sizeof(oparams->intervals));
3901 	oparams->rmask = __NEW_TO_OLD_MASK(params->rmask);
3902 	oparams->cmask = __NEW_TO_OLD_MASK(params->cmask);
3903 	oparams->info = params->info;
3904 	oparams->msbits = params->msbits;
3905 	oparams->rate_num = params->rate_num;
3906 	oparams->rate_den = params->rate_den;
3907 	oparams->fifo_size = params->fifo_size;
3908 }
3909 
3910 static int snd_pcm_hw_refine_old_user(struct snd_pcm_substream *substream,
3911 				      struct snd_pcm_hw_params_old __user * _oparams)
3912 {
3913 	struct snd_pcm_hw_params *params;
3914 	struct snd_pcm_hw_params_old *oparams = NULL;
3915 	int err;
3916 
3917 	params = kmalloc(sizeof(*params), GFP_KERNEL);
3918 	if (!params)
3919 		return -ENOMEM;
3920 
3921 	oparams = memdup_user(_oparams, sizeof(*oparams));
3922 	if (IS_ERR(oparams)) {
3923 		err = PTR_ERR(oparams);
3924 		goto out;
3925 	}
3926 	snd_pcm_hw_convert_from_old_params(params, oparams);
3927 	err = snd_pcm_hw_refine(substream, params);
3928 	if (err < 0)
3929 		goto out_old;
3930 
3931 	err = fixup_unreferenced_params(substream, params);
3932 	if (err < 0)
3933 		goto out_old;
3934 
3935 	snd_pcm_hw_convert_to_old_params(oparams, params);
3936 	if (copy_to_user(_oparams, oparams, sizeof(*oparams)))
3937 		err = -EFAULT;
3938 out_old:
3939 	kfree(oparams);
3940 out:
3941 	kfree(params);
3942 	return err;
3943 }
3944 
3945 static int snd_pcm_hw_params_old_user(struct snd_pcm_substream *substream,
3946 				      struct snd_pcm_hw_params_old __user * _oparams)
3947 {
3948 	struct snd_pcm_hw_params *params;
3949 	struct snd_pcm_hw_params_old *oparams = NULL;
3950 	int err;
3951 
3952 	params = kmalloc(sizeof(*params), GFP_KERNEL);
3953 	if (!params)
3954 		return -ENOMEM;
3955 
3956 	oparams = memdup_user(_oparams, sizeof(*oparams));
3957 	if (IS_ERR(oparams)) {
3958 		err = PTR_ERR(oparams);
3959 		goto out;
3960 	}
3961 
3962 	snd_pcm_hw_convert_from_old_params(params, oparams);
3963 	err = snd_pcm_hw_params(substream, params);
3964 	if (err < 0)
3965 		goto out_old;
3966 
3967 	snd_pcm_hw_convert_to_old_params(oparams, params);
3968 	if (copy_to_user(_oparams, oparams, sizeof(*oparams)))
3969 		err = -EFAULT;
3970 out_old:
3971 	kfree(oparams);
3972 out:
3973 	kfree(params);
3974 	return err;
3975 }
3976 #endif /* CONFIG_SND_SUPPORT_OLD_API */
3977 
3978 #ifndef CONFIG_MMU
3979 static unsigned long snd_pcm_get_unmapped_area(struct file *file,
3980 					       unsigned long addr,
3981 					       unsigned long len,
3982 					       unsigned long pgoff,
3983 					       unsigned long flags)
3984 {
3985 	struct snd_pcm_file *pcm_file = file->private_data;
3986 	struct snd_pcm_substream *substream = pcm_file->substream;
3987 	struct snd_pcm_runtime *runtime = substream->runtime;
3988 	unsigned long offset = pgoff << PAGE_SHIFT;
3989 
3990 	switch (offset) {
3991 	case SNDRV_PCM_MMAP_OFFSET_STATUS_NEW:
3992 		return (unsigned long)runtime->status;
3993 	case SNDRV_PCM_MMAP_OFFSET_CONTROL_NEW:
3994 		return (unsigned long)runtime->control;
3995 	default:
3996 		return (unsigned long)runtime->dma_area + offset;
3997 	}
3998 }
3999 #else
4000 # define snd_pcm_get_unmapped_area NULL
4001 #endif
4002 
4003 /*
4004  *  Register section
4005  */
4006 
4007 const struct file_operations snd_pcm_f_ops[2] = {
4008 	{
4009 		.owner =		THIS_MODULE,
4010 		.write =		snd_pcm_write,
4011 		.write_iter =		snd_pcm_writev,
4012 		.open =			snd_pcm_playback_open,
4013 		.release =		snd_pcm_release,
4014 		.llseek =		no_llseek,
4015 		.poll =			snd_pcm_poll,
4016 		.unlocked_ioctl =	snd_pcm_ioctl,
4017 		.compat_ioctl = 	snd_pcm_ioctl_compat,
4018 		.mmap =			snd_pcm_mmap,
4019 		.fasync =		snd_pcm_fasync,
4020 		.get_unmapped_area =	snd_pcm_get_unmapped_area,
4021 	},
4022 	{
4023 		.owner =		THIS_MODULE,
4024 		.read =			snd_pcm_read,
4025 		.read_iter =		snd_pcm_readv,
4026 		.open =			snd_pcm_capture_open,
4027 		.release =		snd_pcm_release,
4028 		.llseek =		no_llseek,
4029 		.poll =			snd_pcm_poll,
4030 		.unlocked_ioctl =	snd_pcm_ioctl,
4031 		.compat_ioctl = 	snd_pcm_ioctl_compat,
4032 		.mmap =			snd_pcm_mmap,
4033 		.fasync =		snd_pcm_fasync,
4034 		.get_unmapped_area =	snd_pcm_get_unmapped_area,
4035 	}
4036 };
4037