xref: /openbmc/linux/sound/core/pcm_native.c (revision 5a170e9e)
1 /*
2  *  Digital Audio (PCM) abstract layer
3  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4  *
5  *
6  *   This program is free software; you can redistribute it and/or modify
7  *   it under the terms of the GNU General Public License as published by
8  *   the Free Software Foundation; either version 2 of the License, or
9  *   (at your option) any later version.
10  *
11  *   This program is distributed in the hope that it will be useful,
12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *   GNU General Public License for more details.
15  *
16  *   You should have received a copy of the GNU General Public License
17  *   along with this program; if not, write to the Free Software
18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
19  *
20  */
21 
22 #include <linux/mm.h>
23 #include <linux/module.h>
24 #include <linux/file.h>
25 #include <linux/slab.h>
26 #include <linux/sched/signal.h>
27 #include <linux/time.h>
28 #include <linux/pm_qos.h>
29 #include <linux/io.h>
30 #include <linux/dma-mapping.h>
31 #include <sound/core.h>
32 #include <sound/control.h>
33 #include <sound/info.h>
34 #include <sound/pcm.h>
35 #include <sound/pcm_params.h>
36 #include <sound/timer.h>
37 #include <sound/minors.h>
38 #include <linux/uio.h>
39 #include <linux/delay.h>
40 
41 #include "pcm_local.h"
42 
43 #ifdef CONFIG_SND_DEBUG
44 #define CREATE_TRACE_POINTS
45 #include "pcm_param_trace.h"
46 #else
47 #define trace_hw_mask_param_enabled()		0
48 #define trace_hw_interval_param_enabled()	0
49 #define trace_hw_mask_param(substream, type, index, prev, curr)
50 #define trace_hw_interval_param(substream, type, index, prev, curr)
51 #endif
52 
53 /*
54  *  Compatibility
55  */
56 
57 struct snd_pcm_hw_params_old {
58 	unsigned int flags;
59 	unsigned int masks[SNDRV_PCM_HW_PARAM_SUBFORMAT -
60 			   SNDRV_PCM_HW_PARAM_ACCESS + 1];
61 	struct snd_interval intervals[SNDRV_PCM_HW_PARAM_TICK_TIME -
62 					SNDRV_PCM_HW_PARAM_SAMPLE_BITS + 1];
63 	unsigned int rmask;
64 	unsigned int cmask;
65 	unsigned int info;
66 	unsigned int msbits;
67 	unsigned int rate_num;
68 	unsigned int rate_den;
69 	snd_pcm_uframes_t fifo_size;
70 	unsigned char reserved[64];
71 };
72 
73 #ifdef CONFIG_SND_SUPPORT_OLD_API
74 #define SNDRV_PCM_IOCTL_HW_REFINE_OLD _IOWR('A', 0x10, struct snd_pcm_hw_params_old)
75 #define SNDRV_PCM_IOCTL_HW_PARAMS_OLD _IOWR('A', 0x11, struct snd_pcm_hw_params_old)
76 
77 static int snd_pcm_hw_refine_old_user(struct snd_pcm_substream *substream,
78 				      struct snd_pcm_hw_params_old __user * _oparams);
79 static int snd_pcm_hw_params_old_user(struct snd_pcm_substream *substream,
80 				      struct snd_pcm_hw_params_old __user * _oparams);
81 #endif
82 static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream);
83 
84 /*
85  *
86  */
87 
88 static DECLARE_RWSEM(snd_pcm_link_rwsem);
89 
90 void snd_pcm_group_init(struct snd_pcm_group *group)
91 {
92 	spin_lock_init(&group->lock);
93 	mutex_init(&group->mutex);
94 	INIT_LIST_HEAD(&group->substreams);
95 	refcount_set(&group->refs, 0);
96 }
97 
98 /* define group lock helpers */
99 #define DEFINE_PCM_GROUP_LOCK(action, mutex_action) \
100 static void snd_pcm_group_ ## action(struct snd_pcm_group *group, bool nonatomic) \
101 { \
102 	if (nonatomic) \
103 		mutex_ ## mutex_action(&group->mutex); \
104 	else \
105 		spin_ ## action(&group->lock); \
106 }
107 
108 DEFINE_PCM_GROUP_LOCK(lock, lock);
109 DEFINE_PCM_GROUP_LOCK(unlock, unlock);
110 DEFINE_PCM_GROUP_LOCK(lock_irq, lock);
111 DEFINE_PCM_GROUP_LOCK(unlock_irq, unlock);
112 
113 /**
114  * snd_pcm_stream_lock - Lock the PCM stream
115  * @substream: PCM substream
116  *
117  * This locks the PCM stream's spinlock or mutex depending on the nonatomic
118  * flag of the given substream.  This also takes the global link rw lock
119  * (or rw sem), too, for avoiding the race with linked streams.
120  */
121 void snd_pcm_stream_lock(struct snd_pcm_substream *substream)
122 {
123 	snd_pcm_group_lock(&substream->self_group, substream->pcm->nonatomic);
124 }
125 EXPORT_SYMBOL_GPL(snd_pcm_stream_lock);
126 
127 /**
128  * snd_pcm_stream_lock - Unlock the PCM stream
129  * @substream: PCM substream
130  *
131  * This unlocks the PCM stream that has been locked via snd_pcm_stream_lock().
132  */
133 void snd_pcm_stream_unlock(struct snd_pcm_substream *substream)
134 {
135 	snd_pcm_group_unlock(&substream->self_group, substream->pcm->nonatomic);
136 }
137 EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock);
138 
139 /**
140  * snd_pcm_stream_lock_irq - Lock the PCM stream
141  * @substream: PCM substream
142  *
143  * This locks the PCM stream like snd_pcm_stream_lock() and disables the local
144  * IRQ (only when nonatomic is false).  In nonatomic case, this is identical
145  * as snd_pcm_stream_lock().
146  */
147 void snd_pcm_stream_lock_irq(struct snd_pcm_substream *substream)
148 {
149 	snd_pcm_group_lock_irq(&substream->self_group,
150 			       substream->pcm->nonatomic);
151 }
152 EXPORT_SYMBOL_GPL(snd_pcm_stream_lock_irq);
153 
154 /**
155  * snd_pcm_stream_unlock_irq - Unlock the PCM stream
156  * @substream: PCM substream
157  *
158  * This is a counter-part of snd_pcm_stream_lock_irq().
159  */
160 void snd_pcm_stream_unlock_irq(struct snd_pcm_substream *substream)
161 {
162 	snd_pcm_group_unlock_irq(&substream->self_group,
163 				 substream->pcm->nonatomic);
164 }
165 EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irq);
166 
167 unsigned long _snd_pcm_stream_lock_irqsave(struct snd_pcm_substream *substream)
168 {
169 	unsigned long flags = 0;
170 	if (substream->pcm->nonatomic)
171 		mutex_lock(&substream->self_group.mutex);
172 	else
173 		spin_lock_irqsave(&substream->self_group.lock, flags);
174 	return flags;
175 }
176 EXPORT_SYMBOL_GPL(_snd_pcm_stream_lock_irqsave);
177 
178 /**
179  * snd_pcm_stream_unlock_irqrestore - Unlock the PCM stream
180  * @substream: PCM substream
181  * @flags: irq flags
182  *
183  * This is a counter-part of snd_pcm_stream_lock_irqsave().
184  */
185 void snd_pcm_stream_unlock_irqrestore(struct snd_pcm_substream *substream,
186 				      unsigned long flags)
187 {
188 	if (substream->pcm->nonatomic)
189 		mutex_unlock(&substream->self_group.mutex);
190 	else
191 		spin_unlock_irqrestore(&substream->self_group.lock, flags);
192 }
193 EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irqrestore);
194 
195 int snd_pcm_info(struct snd_pcm_substream *substream, struct snd_pcm_info *info)
196 {
197 	struct snd_pcm *pcm = substream->pcm;
198 	struct snd_pcm_str *pstr = substream->pstr;
199 
200 	memset(info, 0, sizeof(*info));
201 	info->card = pcm->card->number;
202 	info->device = pcm->device;
203 	info->stream = substream->stream;
204 	info->subdevice = substream->number;
205 	strlcpy(info->id, pcm->id, sizeof(info->id));
206 	strlcpy(info->name, pcm->name, sizeof(info->name));
207 	info->dev_class = pcm->dev_class;
208 	info->dev_subclass = pcm->dev_subclass;
209 	info->subdevices_count = pstr->substream_count;
210 	info->subdevices_avail = pstr->substream_count - pstr->substream_opened;
211 	strlcpy(info->subname, substream->name, sizeof(info->subname));
212 
213 	return 0;
214 }
215 
216 int snd_pcm_info_user(struct snd_pcm_substream *substream,
217 		      struct snd_pcm_info __user * _info)
218 {
219 	struct snd_pcm_info *info;
220 	int err;
221 
222 	info = kmalloc(sizeof(*info), GFP_KERNEL);
223 	if (! info)
224 		return -ENOMEM;
225 	err = snd_pcm_info(substream, info);
226 	if (err >= 0) {
227 		if (copy_to_user(_info, info, sizeof(*info)))
228 			err = -EFAULT;
229 	}
230 	kfree(info);
231 	return err;
232 }
233 
234 static bool hw_support_mmap(struct snd_pcm_substream *substream)
235 {
236 	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP))
237 		return false;
238 	/* architecture supports dma_mmap_coherent()? */
239 #if defined(CONFIG_ARCH_NO_COHERENT_DMA_MMAP) || !defined(CONFIG_HAS_DMA)
240 	if (!substream->ops->mmap &&
241 	    substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV)
242 		return false;
243 #endif
244 	return true;
245 }
246 
247 static int constrain_mask_params(struct snd_pcm_substream *substream,
248 				 struct snd_pcm_hw_params *params)
249 {
250 	struct snd_pcm_hw_constraints *constrs =
251 					&substream->runtime->hw_constraints;
252 	struct snd_mask *m;
253 	unsigned int k;
254 	struct snd_mask old_mask;
255 	int changed;
256 
257 	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++) {
258 		m = hw_param_mask(params, k);
259 		if (snd_mask_empty(m))
260 			return -EINVAL;
261 
262 		/* This parameter is not requested to change by a caller. */
263 		if (!(params->rmask & (1 << k)))
264 			continue;
265 
266 		if (trace_hw_mask_param_enabled())
267 			old_mask = *m;
268 
269 		changed = snd_mask_refine(m, constrs_mask(constrs, k));
270 		if (changed < 0)
271 			return changed;
272 		if (changed == 0)
273 			continue;
274 
275 		/* Set corresponding flag so that the caller gets it. */
276 		trace_hw_mask_param(substream, k, 0, &old_mask, m);
277 		params->cmask |= 1 << k;
278 	}
279 
280 	return 0;
281 }
282 
283 static int constrain_interval_params(struct snd_pcm_substream *substream,
284 				     struct snd_pcm_hw_params *params)
285 {
286 	struct snd_pcm_hw_constraints *constrs =
287 					&substream->runtime->hw_constraints;
288 	struct snd_interval *i;
289 	unsigned int k;
290 	struct snd_interval old_interval;
291 	int changed;
292 
293 	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++) {
294 		i = hw_param_interval(params, k);
295 		if (snd_interval_empty(i))
296 			return -EINVAL;
297 
298 		/* This parameter is not requested to change by a caller. */
299 		if (!(params->rmask & (1 << k)))
300 			continue;
301 
302 		if (trace_hw_interval_param_enabled())
303 			old_interval = *i;
304 
305 		changed = snd_interval_refine(i, constrs_interval(constrs, k));
306 		if (changed < 0)
307 			return changed;
308 		if (changed == 0)
309 			continue;
310 
311 		/* Set corresponding flag so that the caller gets it. */
312 		trace_hw_interval_param(substream, k, 0, &old_interval, i);
313 		params->cmask |= 1 << k;
314 	}
315 
316 	return 0;
317 }
318 
319 static int constrain_params_by_rules(struct snd_pcm_substream *substream,
320 				     struct snd_pcm_hw_params *params)
321 {
322 	struct snd_pcm_hw_constraints *constrs =
323 					&substream->runtime->hw_constraints;
324 	unsigned int k;
325 	unsigned int *rstamps;
326 	unsigned int vstamps[SNDRV_PCM_HW_PARAM_LAST_INTERVAL + 1];
327 	unsigned int stamp;
328 	struct snd_pcm_hw_rule *r;
329 	unsigned int d;
330 	struct snd_mask old_mask;
331 	struct snd_interval old_interval;
332 	bool again;
333 	int changed, err = 0;
334 
335 	/*
336 	 * Each application of rule has own sequence number.
337 	 *
338 	 * Each member of 'rstamps' array represents the sequence number of
339 	 * recent application of corresponding rule.
340 	 */
341 	rstamps = kcalloc(constrs->rules_num, sizeof(unsigned int), GFP_KERNEL);
342 	if (!rstamps)
343 		return -ENOMEM;
344 
345 	/*
346 	 * Each member of 'vstamps' array represents the sequence number of
347 	 * recent application of rule in which corresponding parameters were
348 	 * changed.
349 	 *
350 	 * In initial state, elements corresponding to parameters requested by
351 	 * a caller is 1. For unrequested parameters, corresponding members
352 	 * have 0 so that the parameters are never changed anymore.
353 	 */
354 	for (k = 0; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
355 		vstamps[k] = (params->rmask & (1 << k)) ? 1 : 0;
356 
357 	/* Due to the above design, actual sequence number starts at 2. */
358 	stamp = 2;
359 retry:
360 	/* Apply all rules in order. */
361 	again = false;
362 	for (k = 0; k < constrs->rules_num; k++) {
363 		r = &constrs->rules[k];
364 
365 		/*
366 		 * Check condition bits of this rule. When the rule has
367 		 * some condition bits, parameter without the bits is
368 		 * never processed. SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP
369 		 * is an example of the condition bits.
370 		 */
371 		if (r->cond && !(r->cond & params->flags))
372 			continue;
373 
374 		/*
375 		 * The 'deps' array includes maximum three dependencies
376 		 * to SNDRV_PCM_HW_PARAM_XXXs for this rule. The fourth
377 		 * member of this array is a sentinel and should be
378 		 * negative value.
379 		 *
380 		 * This rule should be processed in this time when dependent
381 		 * parameters were changed at former applications of the other
382 		 * rules.
383 		 */
384 		for (d = 0; r->deps[d] >= 0; d++) {
385 			if (vstamps[r->deps[d]] > rstamps[k])
386 				break;
387 		}
388 		if (r->deps[d] < 0)
389 			continue;
390 
391 		if (trace_hw_mask_param_enabled()) {
392 			if (hw_is_mask(r->var))
393 				old_mask = *hw_param_mask(params, r->var);
394 		}
395 		if (trace_hw_interval_param_enabled()) {
396 			if (hw_is_interval(r->var))
397 				old_interval = *hw_param_interval(params, r->var);
398 		}
399 
400 		changed = r->func(params, r);
401 		if (changed < 0) {
402 			err = changed;
403 			goto out;
404 		}
405 
406 		/*
407 		 * When the parameter is changed, notify it to the caller
408 		 * by corresponding returned bit, then preparing for next
409 		 * iteration.
410 		 */
411 		if (changed && r->var >= 0) {
412 			if (hw_is_mask(r->var)) {
413 				trace_hw_mask_param(substream, r->var,
414 					k + 1, &old_mask,
415 					hw_param_mask(params, r->var));
416 			}
417 			if (hw_is_interval(r->var)) {
418 				trace_hw_interval_param(substream, r->var,
419 					k + 1, &old_interval,
420 					hw_param_interval(params, r->var));
421 			}
422 
423 			params->cmask |= (1 << r->var);
424 			vstamps[r->var] = stamp;
425 			again = true;
426 		}
427 
428 		rstamps[k] = stamp++;
429 	}
430 
431 	/* Iterate to evaluate all rules till no parameters are changed. */
432 	if (again)
433 		goto retry;
434 
435  out:
436 	kfree(rstamps);
437 	return err;
438 }
439 
440 static int fixup_unreferenced_params(struct snd_pcm_substream *substream,
441 				     struct snd_pcm_hw_params *params)
442 {
443 	const struct snd_interval *i;
444 	const struct snd_mask *m;
445 	int err;
446 
447 	if (!params->msbits) {
448 		i = hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
449 		if (snd_interval_single(i))
450 			params->msbits = snd_interval_value(i);
451 	}
452 
453 	if (!params->rate_den) {
454 		i = hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_RATE);
455 		if (snd_interval_single(i)) {
456 			params->rate_num = snd_interval_value(i);
457 			params->rate_den = 1;
458 		}
459 	}
460 
461 	if (!params->fifo_size) {
462 		m = hw_param_mask_c(params, SNDRV_PCM_HW_PARAM_FORMAT);
463 		i = hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_CHANNELS);
464 		if (snd_mask_single(m) && snd_interval_single(i)) {
465 			err = substream->ops->ioctl(substream,
466 					SNDRV_PCM_IOCTL1_FIFO_SIZE, params);
467 			if (err < 0)
468 				return err;
469 		}
470 	}
471 
472 	if (!params->info) {
473 		params->info = substream->runtime->hw.info;
474 		params->info &= ~(SNDRV_PCM_INFO_FIFO_IN_FRAMES |
475 				  SNDRV_PCM_INFO_DRAIN_TRIGGER);
476 		if (!hw_support_mmap(substream))
477 			params->info &= ~(SNDRV_PCM_INFO_MMAP |
478 					  SNDRV_PCM_INFO_MMAP_VALID);
479 	}
480 
481 	return 0;
482 }
483 
484 int snd_pcm_hw_refine(struct snd_pcm_substream *substream,
485 		      struct snd_pcm_hw_params *params)
486 {
487 	int err;
488 
489 	params->info = 0;
490 	params->fifo_size = 0;
491 	if (params->rmask & (1 << SNDRV_PCM_HW_PARAM_SAMPLE_BITS))
492 		params->msbits = 0;
493 	if (params->rmask & (1 << SNDRV_PCM_HW_PARAM_RATE)) {
494 		params->rate_num = 0;
495 		params->rate_den = 0;
496 	}
497 
498 	err = constrain_mask_params(substream, params);
499 	if (err < 0)
500 		return err;
501 
502 	err = constrain_interval_params(substream, params);
503 	if (err < 0)
504 		return err;
505 
506 	err = constrain_params_by_rules(substream, params);
507 	if (err < 0)
508 		return err;
509 
510 	params->rmask = 0;
511 
512 	return 0;
513 }
514 EXPORT_SYMBOL(snd_pcm_hw_refine);
515 
516 static int snd_pcm_hw_refine_user(struct snd_pcm_substream *substream,
517 				  struct snd_pcm_hw_params __user * _params)
518 {
519 	struct snd_pcm_hw_params *params;
520 	int err;
521 
522 	params = memdup_user(_params, sizeof(*params));
523 	if (IS_ERR(params))
524 		return PTR_ERR(params);
525 
526 	err = snd_pcm_hw_refine(substream, params);
527 	if (err < 0)
528 		goto end;
529 
530 	err = fixup_unreferenced_params(substream, params);
531 	if (err < 0)
532 		goto end;
533 
534 	if (copy_to_user(_params, params, sizeof(*params)))
535 		err = -EFAULT;
536 end:
537 	kfree(params);
538 	return err;
539 }
540 
541 static int period_to_usecs(struct snd_pcm_runtime *runtime)
542 {
543 	int usecs;
544 
545 	if (! runtime->rate)
546 		return -1; /* invalid */
547 
548 	/* take 75% of period time as the deadline */
549 	usecs = (750000 / runtime->rate) * runtime->period_size;
550 	usecs += ((750000 % runtime->rate) * runtime->period_size) /
551 		runtime->rate;
552 
553 	return usecs;
554 }
555 
556 static void snd_pcm_set_state(struct snd_pcm_substream *substream, int state)
557 {
558 	snd_pcm_stream_lock_irq(substream);
559 	if (substream->runtime->status->state != SNDRV_PCM_STATE_DISCONNECTED)
560 		substream->runtime->status->state = state;
561 	snd_pcm_stream_unlock_irq(substream);
562 }
563 
564 static inline void snd_pcm_timer_notify(struct snd_pcm_substream *substream,
565 					int event)
566 {
567 #ifdef CONFIG_SND_PCM_TIMER
568 	if (substream->timer)
569 		snd_timer_notify(substream->timer, event,
570 					&substream->runtime->trigger_tstamp);
571 #endif
572 }
573 
574 /**
575  * snd_pcm_hw_param_choose - choose a configuration defined by @params
576  * @pcm: PCM instance
577  * @params: the hw_params instance
578  *
579  * Choose one configuration from configuration space defined by @params.
580  * The configuration chosen is that obtained fixing in this order:
581  * first access, first format, first subformat, min channels,
582  * min rate, min period time, max buffer size, min tick time
583  *
584  * Return: Zero if successful, or a negative error code on failure.
585  */
586 static int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
587 				    struct snd_pcm_hw_params *params)
588 {
589 	static const int vars[] = {
590 		SNDRV_PCM_HW_PARAM_ACCESS,
591 		SNDRV_PCM_HW_PARAM_FORMAT,
592 		SNDRV_PCM_HW_PARAM_SUBFORMAT,
593 		SNDRV_PCM_HW_PARAM_CHANNELS,
594 		SNDRV_PCM_HW_PARAM_RATE,
595 		SNDRV_PCM_HW_PARAM_PERIOD_TIME,
596 		SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
597 		SNDRV_PCM_HW_PARAM_TICK_TIME,
598 		-1
599 	};
600 	const int *v;
601 	struct snd_mask old_mask;
602 	struct snd_interval old_interval;
603 	int changed;
604 
605 	for (v = vars; *v != -1; v++) {
606 		/* Keep old parameter to trace. */
607 		if (trace_hw_mask_param_enabled()) {
608 			if (hw_is_mask(*v))
609 				old_mask = *hw_param_mask(params, *v);
610 		}
611 		if (trace_hw_interval_param_enabled()) {
612 			if (hw_is_interval(*v))
613 				old_interval = *hw_param_interval(params, *v);
614 		}
615 		if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
616 			changed = snd_pcm_hw_param_first(pcm, params, *v, NULL);
617 		else
618 			changed = snd_pcm_hw_param_last(pcm, params, *v, NULL);
619 		if (changed < 0)
620 			return changed;
621 		if (changed == 0)
622 			continue;
623 
624 		/* Trace the changed parameter. */
625 		if (hw_is_mask(*v)) {
626 			trace_hw_mask_param(pcm, *v, 0, &old_mask,
627 					    hw_param_mask(params, *v));
628 		}
629 		if (hw_is_interval(*v)) {
630 			trace_hw_interval_param(pcm, *v, 0, &old_interval,
631 						hw_param_interval(params, *v));
632 		}
633 	}
634 
635 	return 0;
636 }
637 
638 static int snd_pcm_hw_params(struct snd_pcm_substream *substream,
639 			     struct snd_pcm_hw_params *params)
640 {
641 	struct snd_pcm_runtime *runtime;
642 	int err, usecs;
643 	unsigned int bits;
644 	snd_pcm_uframes_t frames;
645 
646 	if (PCM_RUNTIME_CHECK(substream))
647 		return -ENXIO;
648 	runtime = substream->runtime;
649 	snd_pcm_stream_lock_irq(substream);
650 	switch (runtime->status->state) {
651 	case SNDRV_PCM_STATE_OPEN:
652 	case SNDRV_PCM_STATE_SETUP:
653 	case SNDRV_PCM_STATE_PREPARED:
654 		break;
655 	default:
656 		snd_pcm_stream_unlock_irq(substream);
657 		return -EBADFD;
658 	}
659 	snd_pcm_stream_unlock_irq(substream);
660 #if IS_ENABLED(CONFIG_SND_PCM_OSS)
661 	if (!substream->oss.oss)
662 #endif
663 		if (atomic_read(&substream->mmap_count))
664 			return -EBADFD;
665 
666 	params->rmask = ~0U;
667 	err = snd_pcm_hw_refine(substream, params);
668 	if (err < 0)
669 		goto _error;
670 
671 	err = snd_pcm_hw_params_choose(substream, params);
672 	if (err < 0)
673 		goto _error;
674 
675 	err = fixup_unreferenced_params(substream, params);
676 	if (err < 0)
677 		goto _error;
678 
679 	if (substream->ops->hw_params != NULL) {
680 		err = substream->ops->hw_params(substream, params);
681 		if (err < 0)
682 			goto _error;
683 	}
684 
685 	runtime->access = params_access(params);
686 	runtime->format = params_format(params);
687 	runtime->subformat = params_subformat(params);
688 	runtime->channels = params_channels(params);
689 	runtime->rate = params_rate(params);
690 	runtime->period_size = params_period_size(params);
691 	runtime->periods = params_periods(params);
692 	runtime->buffer_size = params_buffer_size(params);
693 	runtime->info = params->info;
694 	runtime->rate_num = params->rate_num;
695 	runtime->rate_den = params->rate_den;
696 	runtime->no_period_wakeup =
697 			(params->info & SNDRV_PCM_INFO_NO_PERIOD_WAKEUP) &&
698 			(params->flags & SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP);
699 
700 	bits = snd_pcm_format_physical_width(runtime->format);
701 	runtime->sample_bits = bits;
702 	bits *= runtime->channels;
703 	runtime->frame_bits = bits;
704 	frames = 1;
705 	while (bits % 8 != 0) {
706 		bits *= 2;
707 		frames *= 2;
708 	}
709 	runtime->byte_align = bits / 8;
710 	runtime->min_align = frames;
711 
712 	/* Default sw params */
713 	runtime->tstamp_mode = SNDRV_PCM_TSTAMP_NONE;
714 	runtime->period_step = 1;
715 	runtime->control->avail_min = runtime->period_size;
716 	runtime->start_threshold = 1;
717 	runtime->stop_threshold = runtime->buffer_size;
718 	runtime->silence_threshold = 0;
719 	runtime->silence_size = 0;
720 	runtime->boundary = runtime->buffer_size;
721 	while (runtime->boundary * 2 <= LONG_MAX - runtime->buffer_size)
722 		runtime->boundary *= 2;
723 
724 	snd_pcm_timer_resolution_change(substream);
725 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_SETUP);
726 
727 	if (pm_qos_request_active(&substream->latency_pm_qos_req))
728 		pm_qos_remove_request(&substream->latency_pm_qos_req);
729 	if ((usecs = period_to_usecs(runtime)) >= 0)
730 		pm_qos_add_request(&substream->latency_pm_qos_req,
731 				   PM_QOS_CPU_DMA_LATENCY, usecs);
732 	return 0;
733  _error:
734 	/* hardware might be unusable from this time,
735 	   so we force application to retry to set
736 	   the correct hardware parameter settings */
737 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_OPEN);
738 	if (substream->ops->hw_free != NULL)
739 		substream->ops->hw_free(substream);
740 	return err;
741 }
742 
743 static int snd_pcm_hw_params_user(struct snd_pcm_substream *substream,
744 				  struct snd_pcm_hw_params __user * _params)
745 {
746 	struct snd_pcm_hw_params *params;
747 	int err;
748 
749 	params = memdup_user(_params, sizeof(*params));
750 	if (IS_ERR(params))
751 		return PTR_ERR(params);
752 
753 	err = snd_pcm_hw_params(substream, params);
754 	if (err < 0)
755 		goto end;
756 
757 	if (copy_to_user(_params, params, sizeof(*params)))
758 		err = -EFAULT;
759 end:
760 	kfree(params);
761 	return err;
762 }
763 
764 static int snd_pcm_hw_free(struct snd_pcm_substream *substream)
765 {
766 	struct snd_pcm_runtime *runtime;
767 	int result = 0;
768 
769 	if (PCM_RUNTIME_CHECK(substream))
770 		return -ENXIO;
771 	runtime = substream->runtime;
772 	snd_pcm_stream_lock_irq(substream);
773 	switch (runtime->status->state) {
774 	case SNDRV_PCM_STATE_SETUP:
775 	case SNDRV_PCM_STATE_PREPARED:
776 		break;
777 	default:
778 		snd_pcm_stream_unlock_irq(substream);
779 		return -EBADFD;
780 	}
781 	snd_pcm_stream_unlock_irq(substream);
782 	if (atomic_read(&substream->mmap_count))
783 		return -EBADFD;
784 	if (substream->ops->hw_free)
785 		result = substream->ops->hw_free(substream);
786 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_OPEN);
787 	pm_qos_remove_request(&substream->latency_pm_qos_req);
788 	return result;
789 }
790 
791 static int snd_pcm_sw_params(struct snd_pcm_substream *substream,
792 			     struct snd_pcm_sw_params *params)
793 {
794 	struct snd_pcm_runtime *runtime;
795 	int err;
796 
797 	if (PCM_RUNTIME_CHECK(substream))
798 		return -ENXIO;
799 	runtime = substream->runtime;
800 	snd_pcm_stream_lock_irq(substream);
801 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
802 		snd_pcm_stream_unlock_irq(substream);
803 		return -EBADFD;
804 	}
805 	snd_pcm_stream_unlock_irq(substream);
806 
807 	if (params->tstamp_mode < 0 ||
808 	    params->tstamp_mode > SNDRV_PCM_TSTAMP_LAST)
809 		return -EINVAL;
810 	if (params->proto >= SNDRV_PROTOCOL_VERSION(2, 0, 12) &&
811 	    params->tstamp_type > SNDRV_PCM_TSTAMP_TYPE_LAST)
812 		return -EINVAL;
813 	if (params->avail_min == 0)
814 		return -EINVAL;
815 	if (params->silence_size >= runtime->boundary) {
816 		if (params->silence_threshold != 0)
817 			return -EINVAL;
818 	} else {
819 		if (params->silence_size > params->silence_threshold)
820 			return -EINVAL;
821 		if (params->silence_threshold > runtime->buffer_size)
822 			return -EINVAL;
823 	}
824 	err = 0;
825 	snd_pcm_stream_lock_irq(substream);
826 	runtime->tstamp_mode = params->tstamp_mode;
827 	if (params->proto >= SNDRV_PROTOCOL_VERSION(2, 0, 12))
828 		runtime->tstamp_type = params->tstamp_type;
829 	runtime->period_step = params->period_step;
830 	runtime->control->avail_min = params->avail_min;
831 	runtime->start_threshold = params->start_threshold;
832 	runtime->stop_threshold = params->stop_threshold;
833 	runtime->silence_threshold = params->silence_threshold;
834 	runtime->silence_size = params->silence_size;
835         params->boundary = runtime->boundary;
836 	if (snd_pcm_running(substream)) {
837 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
838 		    runtime->silence_size > 0)
839 			snd_pcm_playback_silence(substream, ULONG_MAX);
840 		err = snd_pcm_update_state(substream, runtime);
841 	}
842 	snd_pcm_stream_unlock_irq(substream);
843 	return err;
844 }
845 
846 static int snd_pcm_sw_params_user(struct snd_pcm_substream *substream,
847 				  struct snd_pcm_sw_params __user * _params)
848 {
849 	struct snd_pcm_sw_params params;
850 	int err;
851 	if (copy_from_user(&params, _params, sizeof(params)))
852 		return -EFAULT;
853 	err = snd_pcm_sw_params(substream, &params);
854 	if (copy_to_user(_params, &params, sizeof(params)))
855 		return -EFAULT;
856 	return err;
857 }
858 
859 static inline snd_pcm_uframes_t
860 snd_pcm_calc_delay(struct snd_pcm_substream *substream)
861 {
862 	snd_pcm_uframes_t delay;
863 
864 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
865 		delay = snd_pcm_playback_hw_avail(substream->runtime);
866 	else
867 		delay = snd_pcm_capture_avail(substream->runtime);
868 	return delay + substream->runtime->delay;
869 }
870 
871 int snd_pcm_status(struct snd_pcm_substream *substream,
872 		   struct snd_pcm_status *status)
873 {
874 	struct snd_pcm_runtime *runtime = substream->runtime;
875 
876 	snd_pcm_stream_lock_irq(substream);
877 
878 	snd_pcm_unpack_audio_tstamp_config(status->audio_tstamp_data,
879 					&runtime->audio_tstamp_config);
880 
881 	/* backwards compatible behavior */
882 	if (runtime->audio_tstamp_config.type_requested ==
883 		SNDRV_PCM_AUDIO_TSTAMP_TYPE_COMPAT) {
884 		if (runtime->hw.info & SNDRV_PCM_INFO_HAS_WALL_CLOCK)
885 			runtime->audio_tstamp_config.type_requested =
886 				SNDRV_PCM_AUDIO_TSTAMP_TYPE_LINK;
887 		else
888 			runtime->audio_tstamp_config.type_requested =
889 				SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT;
890 		runtime->audio_tstamp_report.valid = 0;
891 	} else
892 		runtime->audio_tstamp_report.valid = 1;
893 
894 	status->state = runtime->status->state;
895 	status->suspended_state = runtime->status->suspended_state;
896 	if (status->state == SNDRV_PCM_STATE_OPEN)
897 		goto _end;
898 	status->trigger_tstamp = runtime->trigger_tstamp;
899 	if (snd_pcm_running(substream)) {
900 		snd_pcm_update_hw_ptr(substream);
901 		if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
902 			status->tstamp = runtime->status->tstamp;
903 			status->driver_tstamp = runtime->driver_tstamp;
904 			status->audio_tstamp =
905 				runtime->status->audio_tstamp;
906 			if (runtime->audio_tstamp_report.valid == 1)
907 				/* backwards compatibility, no report provided in COMPAT mode */
908 				snd_pcm_pack_audio_tstamp_report(&status->audio_tstamp_data,
909 								&status->audio_tstamp_accuracy,
910 								&runtime->audio_tstamp_report);
911 
912 			goto _tstamp_end;
913 		}
914 	} else {
915 		/* get tstamp only in fallback mode and only if enabled */
916 		if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
917 			snd_pcm_gettime(runtime, &status->tstamp);
918 	}
919  _tstamp_end:
920 	status->appl_ptr = runtime->control->appl_ptr;
921 	status->hw_ptr = runtime->status->hw_ptr;
922 	status->avail = snd_pcm_avail(substream);
923 	status->delay = snd_pcm_running(substream) ?
924 		snd_pcm_calc_delay(substream) : 0;
925 	status->avail_max = runtime->avail_max;
926 	status->overrange = runtime->overrange;
927 	runtime->avail_max = 0;
928 	runtime->overrange = 0;
929  _end:
930  	snd_pcm_stream_unlock_irq(substream);
931 	return 0;
932 }
933 
934 static int snd_pcm_status_user(struct snd_pcm_substream *substream,
935 			       struct snd_pcm_status __user * _status,
936 			       bool ext)
937 {
938 	struct snd_pcm_status status;
939 	int res;
940 
941 	memset(&status, 0, sizeof(status));
942 	/*
943 	 * with extension, parameters are read/write,
944 	 * get audio_tstamp_data from user,
945 	 * ignore rest of status structure
946 	 */
947 	if (ext && get_user(status.audio_tstamp_data,
948 				(u32 __user *)(&_status->audio_tstamp_data)))
949 		return -EFAULT;
950 	res = snd_pcm_status(substream, &status);
951 	if (res < 0)
952 		return res;
953 	if (copy_to_user(_status, &status, sizeof(status)))
954 		return -EFAULT;
955 	return 0;
956 }
957 
958 static int snd_pcm_channel_info(struct snd_pcm_substream *substream,
959 				struct snd_pcm_channel_info * info)
960 {
961 	struct snd_pcm_runtime *runtime;
962 	unsigned int channel;
963 
964 	channel = info->channel;
965 	runtime = substream->runtime;
966 	snd_pcm_stream_lock_irq(substream);
967 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN) {
968 		snd_pcm_stream_unlock_irq(substream);
969 		return -EBADFD;
970 	}
971 	snd_pcm_stream_unlock_irq(substream);
972 	if (channel >= runtime->channels)
973 		return -EINVAL;
974 	memset(info, 0, sizeof(*info));
975 	info->channel = channel;
976 	return substream->ops->ioctl(substream, SNDRV_PCM_IOCTL1_CHANNEL_INFO, info);
977 }
978 
979 static int snd_pcm_channel_info_user(struct snd_pcm_substream *substream,
980 				     struct snd_pcm_channel_info __user * _info)
981 {
982 	struct snd_pcm_channel_info info;
983 	int res;
984 
985 	if (copy_from_user(&info, _info, sizeof(info)))
986 		return -EFAULT;
987 	res = snd_pcm_channel_info(substream, &info);
988 	if (res < 0)
989 		return res;
990 	if (copy_to_user(_info, &info, sizeof(info)))
991 		return -EFAULT;
992 	return 0;
993 }
994 
995 static void snd_pcm_trigger_tstamp(struct snd_pcm_substream *substream)
996 {
997 	struct snd_pcm_runtime *runtime = substream->runtime;
998 	if (runtime->trigger_master == NULL)
999 		return;
1000 	if (runtime->trigger_master == substream) {
1001 		if (!runtime->trigger_tstamp_latched)
1002 			snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
1003 	} else {
1004 		snd_pcm_trigger_tstamp(runtime->trigger_master);
1005 		runtime->trigger_tstamp = runtime->trigger_master->runtime->trigger_tstamp;
1006 	}
1007 	runtime->trigger_master = NULL;
1008 }
1009 
1010 struct action_ops {
1011 	int (*pre_action)(struct snd_pcm_substream *substream, int state);
1012 	int (*do_action)(struct snd_pcm_substream *substream, int state);
1013 	void (*undo_action)(struct snd_pcm_substream *substream, int state);
1014 	void (*post_action)(struct snd_pcm_substream *substream, int state);
1015 };
1016 
1017 /*
1018  *  this functions is core for handling of linked stream
1019  *  Note: the stream state might be changed also on failure
1020  *  Note2: call with calling stream lock + link lock
1021  */
1022 static int snd_pcm_action_group(const struct action_ops *ops,
1023 				struct snd_pcm_substream *substream,
1024 				int state, int do_lock)
1025 {
1026 	struct snd_pcm_substream *s = NULL;
1027 	struct snd_pcm_substream *s1;
1028 	int res = 0, depth = 1;
1029 
1030 	snd_pcm_group_for_each_entry(s, substream) {
1031 		if (do_lock && s != substream) {
1032 			if (s->pcm->nonatomic)
1033 				mutex_lock_nested(&s->self_group.mutex, depth);
1034 			else
1035 				spin_lock_nested(&s->self_group.lock, depth);
1036 			depth++;
1037 		}
1038 		res = ops->pre_action(s, state);
1039 		if (res < 0)
1040 			goto _unlock;
1041 	}
1042 	snd_pcm_group_for_each_entry(s, substream) {
1043 		res = ops->do_action(s, state);
1044 		if (res < 0) {
1045 			if (ops->undo_action) {
1046 				snd_pcm_group_for_each_entry(s1, substream) {
1047 					if (s1 == s) /* failed stream */
1048 						break;
1049 					ops->undo_action(s1, state);
1050 				}
1051 			}
1052 			s = NULL; /* unlock all */
1053 			goto _unlock;
1054 		}
1055 	}
1056 	snd_pcm_group_for_each_entry(s, substream) {
1057 		ops->post_action(s, state);
1058 	}
1059  _unlock:
1060 	if (do_lock) {
1061 		/* unlock streams */
1062 		snd_pcm_group_for_each_entry(s1, substream) {
1063 			if (s1 != substream) {
1064 				if (s1->pcm->nonatomic)
1065 					mutex_unlock(&s1->self_group.mutex);
1066 				else
1067 					spin_unlock(&s1->self_group.lock);
1068 			}
1069 			if (s1 == s)	/* end */
1070 				break;
1071 		}
1072 	}
1073 	return res;
1074 }
1075 
1076 /*
1077  *  Note: call with stream lock
1078  */
1079 static int snd_pcm_action_single(const struct action_ops *ops,
1080 				 struct snd_pcm_substream *substream,
1081 				 int state)
1082 {
1083 	int res;
1084 
1085 	res = ops->pre_action(substream, state);
1086 	if (res < 0)
1087 		return res;
1088 	res = ops->do_action(substream, state);
1089 	if (res == 0)
1090 		ops->post_action(substream, state);
1091 	else if (ops->undo_action)
1092 		ops->undo_action(substream, state);
1093 	return res;
1094 }
1095 
1096 static void snd_pcm_group_assign(struct snd_pcm_substream *substream,
1097 				 struct snd_pcm_group *new_group)
1098 {
1099 	substream->group = new_group;
1100 	list_move(&substream->link_list, &new_group->substreams);
1101 }
1102 
1103 /*
1104  * Unref and unlock the group, but keep the stream lock;
1105  * when the group becomes empty and no longer referred, destroy itself
1106  */
1107 static void snd_pcm_group_unref(struct snd_pcm_group *group,
1108 				struct snd_pcm_substream *substream)
1109 {
1110 	bool do_free;
1111 
1112 	if (!group)
1113 		return;
1114 	do_free = refcount_dec_and_test(&group->refs) &&
1115 		list_empty(&group->substreams);
1116 	snd_pcm_group_unlock(group, substream->pcm->nonatomic);
1117 	if (do_free)
1118 		kfree(group);
1119 }
1120 
1121 /*
1122  * Lock the group inside a stream lock and reference it;
1123  * return the locked group object, or NULL if not linked
1124  */
1125 static struct snd_pcm_group *
1126 snd_pcm_stream_group_ref(struct snd_pcm_substream *substream)
1127 {
1128 	bool nonatomic = substream->pcm->nonatomic;
1129 	struct snd_pcm_group *group;
1130 	bool trylock;
1131 
1132 	for (;;) {
1133 		if (!snd_pcm_stream_linked(substream))
1134 			return NULL;
1135 		group = substream->group;
1136 		/* block freeing the group object */
1137 		refcount_inc(&group->refs);
1138 
1139 		trylock = nonatomic ? mutex_trylock(&group->mutex) :
1140 			spin_trylock(&group->lock);
1141 		if (trylock)
1142 			break; /* OK */
1143 
1144 		/* re-lock for avoiding ABBA deadlock */
1145 		snd_pcm_stream_unlock(substream);
1146 		snd_pcm_group_lock(group, nonatomic);
1147 		snd_pcm_stream_lock(substream);
1148 
1149 		/* check the group again; the above opens a small race window */
1150 		if (substream->group == group)
1151 			break; /* OK */
1152 		/* group changed, try again */
1153 		snd_pcm_group_unref(group, substream);
1154 	}
1155 	return group;
1156 }
1157 
1158 /*
1159  *  Note: call with stream lock
1160  */
1161 static int snd_pcm_action(const struct action_ops *ops,
1162 			  struct snd_pcm_substream *substream,
1163 			  int state)
1164 {
1165 	struct snd_pcm_group *group;
1166 	int res;
1167 
1168 	group = snd_pcm_stream_group_ref(substream);
1169 	if (group)
1170 		res = snd_pcm_action_group(ops, substream, state, 1);
1171 	else
1172 		res = snd_pcm_action_single(ops, substream, state);
1173 	snd_pcm_group_unref(group, substream);
1174 	return res;
1175 }
1176 
1177 /*
1178  *  Note: don't use any locks before
1179  */
1180 static int snd_pcm_action_lock_irq(const struct action_ops *ops,
1181 				   struct snd_pcm_substream *substream,
1182 				   int state)
1183 {
1184 	int res;
1185 
1186 	snd_pcm_stream_lock_irq(substream);
1187 	res = snd_pcm_action(ops, substream, state);
1188 	snd_pcm_stream_unlock_irq(substream);
1189 	return res;
1190 }
1191 
1192 /*
1193  */
1194 static int snd_pcm_action_nonatomic(const struct action_ops *ops,
1195 				    struct snd_pcm_substream *substream,
1196 				    int state)
1197 {
1198 	int res;
1199 
1200 	/* Guarantee the group members won't change during non-atomic action */
1201 	down_read(&snd_pcm_link_rwsem);
1202 	if (snd_pcm_stream_linked(substream))
1203 		res = snd_pcm_action_group(ops, substream, state, 0);
1204 	else
1205 		res = snd_pcm_action_single(ops, substream, state);
1206 	up_read(&snd_pcm_link_rwsem);
1207 	return res;
1208 }
1209 
1210 /*
1211  * start callbacks
1212  */
1213 static int snd_pcm_pre_start(struct snd_pcm_substream *substream, int state)
1214 {
1215 	struct snd_pcm_runtime *runtime = substream->runtime;
1216 	if (runtime->status->state != SNDRV_PCM_STATE_PREPARED)
1217 		return -EBADFD;
1218 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
1219 	    !snd_pcm_playback_data(substream))
1220 		return -EPIPE;
1221 	runtime->trigger_tstamp_latched = false;
1222 	runtime->trigger_master = substream;
1223 	return 0;
1224 }
1225 
1226 static int snd_pcm_do_start(struct snd_pcm_substream *substream, int state)
1227 {
1228 	if (substream->runtime->trigger_master != substream)
1229 		return 0;
1230 	return substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_START);
1231 }
1232 
1233 static void snd_pcm_undo_start(struct snd_pcm_substream *substream, int state)
1234 {
1235 	if (substream->runtime->trigger_master == substream)
1236 		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_STOP);
1237 }
1238 
1239 static void snd_pcm_post_start(struct snd_pcm_substream *substream, int state)
1240 {
1241 	struct snd_pcm_runtime *runtime = substream->runtime;
1242 	snd_pcm_trigger_tstamp(substream);
1243 	runtime->hw_ptr_jiffies = jiffies;
1244 	runtime->hw_ptr_buffer_jiffies = (runtime->buffer_size * HZ) /
1245 							    runtime->rate;
1246 	runtime->status->state = state;
1247 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
1248 	    runtime->silence_size > 0)
1249 		snd_pcm_playback_silence(substream, ULONG_MAX);
1250 	snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MSTART);
1251 }
1252 
1253 static const struct action_ops snd_pcm_action_start = {
1254 	.pre_action = snd_pcm_pre_start,
1255 	.do_action = snd_pcm_do_start,
1256 	.undo_action = snd_pcm_undo_start,
1257 	.post_action = snd_pcm_post_start
1258 };
1259 
1260 /**
1261  * snd_pcm_start - start all linked streams
1262  * @substream: the PCM substream instance
1263  *
1264  * Return: Zero if successful, or a negative error code.
1265  * The stream lock must be acquired before calling this function.
1266  */
1267 int snd_pcm_start(struct snd_pcm_substream *substream)
1268 {
1269 	return snd_pcm_action(&snd_pcm_action_start, substream,
1270 			      SNDRV_PCM_STATE_RUNNING);
1271 }
1272 
1273 /* take the stream lock and start the streams */
1274 static int snd_pcm_start_lock_irq(struct snd_pcm_substream *substream)
1275 {
1276 	return snd_pcm_action_lock_irq(&snd_pcm_action_start, substream,
1277 				       SNDRV_PCM_STATE_RUNNING);
1278 }
1279 
1280 /*
1281  * stop callbacks
1282  */
1283 static int snd_pcm_pre_stop(struct snd_pcm_substream *substream, int state)
1284 {
1285 	struct snd_pcm_runtime *runtime = substream->runtime;
1286 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1287 		return -EBADFD;
1288 	runtime->trigger_master = substream;
1289 	return 0;
1290 }
1291 
1292 static int snd_pcm_do_stop(struct snd_pcm_substream *substream, int state)
1293 {
1294 	if (substream->runtime->trigger_master == substream &&
1295 	    snd_pcm_running(substream))
1296 		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_STOP);
1297 	return 0; /* unconditonally stop all substreams */
1298 }
1299 
1300 static void snd_pcm_post_stop(struct snd_pcm_substream *substream, int state)
1301 {
1302 	struct snd_pcm_runtime *runtime = substream->runtime;
1303 	if (runtime->status->state != state) {
1304 		snd_pcm_trigger_tstamp(substream);
1305 		runtime->status->state = state;
1306 		snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MSTOP);
1307 	}
1308 	wake_up(&runtime->sleep);
1309 	wake_up(&runtime->tsleep);
1310 }
1311 
1312 static const struct action_ops snd_pcm_action_stop = {
1313 	.pre_action = snd_pcm_pre_stop,
1314 	.do_action = snd_pcm_do_stop,
1315 	.post_action = snd_pcm_post_stop
1316 };
1317 
1318 /**
1319  * snd_pcm_stop - try to stop all running streams in the substream group
1320  * @substream: the PCM substream instance
1321  * @state: PCM state after stopping the stream
1322  *
1323  * The state of each stream is then changed to the given state unconditionally.
1324  *
1325  * Return: Zero if successful, or a negative error code.
1326  */
1327 int snd_pcm_stop(struct snd_pcm_substream *substream, snd_pcm_state_t state)
1328 {
1329 	return snd_pcm_action(&snd_pcm_action_stop, substream, state);
1330 }
1331 EXPORT_SYMBOL(snd_pcm_stop);
1332 
1333 /**
1334  * snd_pcm_drain_done - stop the DMA only when the given stream is playback
1335  * @substream: the PCM substream
1336  *
1337  * After stopping, the state is changed to SETUP.
1338  * Unlike snd_pcm_stop(), this affects only the given stream.
1339  *
1340  * Return: Zero if succesful, or a negative error code.
1341  */
1342 int snd_pcm_drain_done(struct snd_pcm_substream *substream)
1343 {
1344 	return snd_pcm_action_single(&snd_pcm_action_stop, substream,
1345 				     SNDRV_PCM_STATE_SETUP);
1346 }
1347 
1348 /**
1349  * snd_pcm_stop_xrun - stop the running streams as XRUN
1350  * @substream: the PCM substream instance
1351  *
1352  * This stops the given running substream (and all linked substreams) as XRUN.
1353  * Unlike snd_pcm_stop(), this function takes the substream lock by itself.
1354  *
1355  * Return: Zero if successful, or a negative error code.
1356  */
1357 int snd_pcm_stop_xrun(struct snd_pcm_substream *substream)
1358 {
1359 	unsigned long flags;
1360 
1361 	snd_pcm_stream_lock_irqsave(substream, flags);
1362 	if (substream->runtime && snd_pcm_running(substream))
1363 		__snd_pcm_xrun(substream);
1364 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1365 	return 0;
1366 }
1367 EXPORT_SYMBOL_GPL(snd_pcm_stop_xrun);
1368 
1369 /*
1370  * pause callbacks
1371  */
1372 static int snd_pcm_pre_pause(struct snd_pcm_substream *substream, int push)
1373 {
1374 	struct snd_pcm_runtime *runtime = substream->runtime;
1375 	if (!(runtime->info & SNDRV_PCM_INFO_PAUSE))
1376 		return -ENOSYS;
1377 	if (push) {
1378 		if (runtime->status->state != SNDRV_PCM_STATE_RUNNING)
1379 			return -EBADFD;
1380 	} else if (runtime->status->state != SNDRV_PCM_STATE_PAUSED)
1381 		return -EBADFD;
1382 	runtime->trigger_master = substream;
1383 	return 0;
1384 }
1385 
1386 static int snd_pcm_do_pause(struct snd_pcm_substream *substream, int push)
1387 {
1388 	if (substream->runtime->trigger_master != substream)
1389 		return 0;
1390 	/* some drivers might use hw_ptr to recover from the pause -
1391 	   update the hw_ptr now */
1392 	if (push)
1393 		snd_pcm_update_hw_ptr(substream);
1394 	/* The jiffies check in snd_pcm_update_hw_ptr*() is done by
1395 	 * a delta between the current jiffies, this gives a large enough
1396 	 * delta, effectively to skip the check once.
1397 	 */
1398 	substream->runtime->hw_ptr_jiffies = jiffies - HZ * 1000;
1399 	return substream->ops->trigger(substream,
1400 				       push ? SNDRV_PCM_TRIGGER_PAUSE_PUSH :
1401 					      SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
1402 }
1403 
1404 static void snd_pcm_undo_pause(struct snd_pcm_substream *substream, int push)
1405 {
1406 	if (substream->runtime->trigger_master == substream)
1407 		substream->ops->trigger(substream,
1408 					push ? SNDRV_PCM_TRIGGER_PAUSE_RELEASE :
1409 					SNDRV_PCM_TRIGGER_PAUSE_PUSH);
1410 }
1411 
1412 static void snd_pcm_post_pause(struct snd_pcm_substream *substream, int push)
1413 {
1414 	struct snd_pcm_runtime *runtime = substream->runtime;
1415 	snd_pcm_trigger_tstamp(substream);
1416 	if (push) {
1417 		runtime->status->state = SNDRV_PCM_STATE_PAUSED;
1418 		snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MPAUSE);
1419 		wake_up(&runtime->sleep);
1420 		wake_up(&runtime->tsleep);
1421 	} else {
1422 		runtime->status->state = SNDRV_PCM_STATE_RUNNING;
1423 		snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MCONTINUE);
1424 	}
1425 }
1426 
1427 static const struct action_ops snd_pcm_action_pause = {
1428 	.pre_action = snd_pcm_pre_pause,
1429 	.do_action = snd_pcm_do_pause,
1430 	.undo_action = snd_pcm_undo_pause,
1431 	.post_action = snd_pcm_post_pause
1432 };
1433 
1434 /*
1435  * Push/release the pause for all linked streams.
1436  */
1437 static int snd_pcm_pause(struct snd_pcm_substream *substream, int push)
1438 {
1439 	return snd_pcm_action(&snd_pcm_action_pause, substream, push);
1440 }
1441 
1442 #ifdef CONFIG_PM
1443 /* suspend */
1444 
1445 static int snd_pcm_pre_suspend(struct snd_pcm_substream *substream, int state)
1446 {
1447 	struct snd_pcm_runtime *runtime = substream->runtime;
1448 	if (runtime->status->state == SNDRV_PCM_STATE_SUSPENDED)
1449 		return -EBUSY;
1450 	runtime->trigger_master = substream;
1451 	return 0;
1452 }
1453 
1454 static int snd_pcm_do_suspend(struct snd_pcm_substream *substream, int state)
1455 {
1456 	struct snd_pcm_runtime *runtime = substream->runtime;
1457 	if (runtime->trigger_master != substream)
1458 		return 0;
1459 	if (! snd_pcm_running(substream))
1460 		return 0;
1461 	substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_SUSPEND);
1462 	return 0; /* suspend unconditionally */
1463 }
1464 
1465 static void snd_pcm_post_suspend(struct snd_pcm_substream *substream, int state)
1466 {
1467 	struct snd_pcm_runtime *runtime = substream->runtime;
1468 	snd_pcm_trigger_tstamp(substream);
1469 	runtime->status->suspended_state = runtime->status->state;
1470 	runtime->status->state = SNDRV_PCM_STATE_SUSPENDED;
1471 	snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MSUSPEND);
1472 	wake_up(&runtime->sleep);
1473 	wake_up(&runtime->tsleep);
1474 }
1475 
1476 static const struct action_ops snd_pcm_action_suspend = {
1477 	.pre_action = snd_pcm_pre_suspend,
1478 	.do_action = snd_pcm_do_suspend,
1479 	.post_action = snd_pcm_post_suspend
1480 };
1481 
1482 /*
1483  * snd_pcm_suspend - trigger SUSPEND to all linked streams
1484  * @substream: the PCM substream
1485  *
1486  * After this call, all streams are changed to SUSPENDED state.
1487  *
1488  * Return: Zero if successful, or a negative error code.
1489  */
1490 static int snd_pcm_suspend(struct snd_pcm_substream *substream)
1491 {
1492 	int err;
1493 	unsigned long flags;
1494 
1495 	snd_pcm_stream_lock_irqsave(substream, flags);
1496 	err = snd_pcm_action(&snd_pcm_action_suspend, substream, 0);
1497 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1498 	return err;
1499 }
1500 
1501 /**
1502  * snd_pcm_suspend_all - trigger SUSPEND to all substreams in the given pcm
1503  * @pcm: the PCM instance
1504  *
1505  * After this call, all streams are changed to SUSPENDED state.
1506  *
1507  * Return: Zero if successful (or @pcm is %NULL), or a negative error code.
1508  */
1509 int snd_pcm_suspend_all(struct snd_pcm *pcm)
1510 {
1511 	struct snd_pcm_substream *substream;
1512 	int stream, err = 0;
1513 
1514 	if (! pcm)
1515 		return 0;
1516 
1517 	for (stream = 0; stream < 2; stream++) {
1518 		for (substream = pcm->streams[stream].substream;
1519 		     substream; substream = substream->next) {
1520 			/* FIXME: the open/close code should lock this as well */
1521 			if (substream->runtime == NULL)
1522 				continue;
1523 			err = snd_pcm_suspend(substream);
1524 			if (err < 0 && err != -EBUSY)
1525 				return err;
1526 		}
1527 	}
1528 	return 0;
1529 }
1530 EXPORT_SYMBOL(snd_pcm_suspend_all);
1531 
1532 /* resume */
1533 
1534 static int snd_pcm_pre_resume(struct snd_pcm_substream *substream, int state)
1535 {
1536 	struct snd_pcm_runtime *runtime = substream->runtime;
1537 	if (!(runtime->info & SNDRV_PCM_INFO_RESUME))
1538 		return -ENOSYS;
1539 	runtime->trigger_master = substream;
1540 	return 0;
1541 }
1542 
1543 static int snd_pcm_do_resume(struct snd_pcm_substream *substream, int state)
1544 {
1545 	struct snd_pcm_runtime *runtime = substream->runtime;
1546 	if (runtime->trigger_master != substream)
1547 		return 0;
1548 	/* DMA not running previously? */
1549 	if (runtime->status->suspended_state != SNDRV_PCM_STATE_RUNNING &&
1550 	    (runtime->status->suspended_state != SNDRV_PCM_STATE_DRAINING ||
1551 	     substream->stream != SNDRV_PCM_STREAM_PLAYBACK))
1552 		return 0;
1553 	return substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_RESUME);
1554 }
1555 
1556 static void snd_pcm_undo_resume(struct snd_pcm_substream *substream, int state)
1557 {
1558 	if (substream->runtime->trigger_master == substream &&
1559 	    snd_pcm_running(substream))
1560 		substream->ops->trigger(substream, SNDRV_PCM_TRIGGER_SUSPEND);
1561 }
1562 
1563 static void snd_pcm_post_resume(struct snd_pcm_substream *substream, int state)
1564 {
1565 	struct snd_pcm_runtime *runtime = substream->runtime;
1566 	snd_pcm_trigger_tstamp(substream);
1567 	runtime->status->state = runtime->status->suspended_state;
1568 	snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MRESUME);
1569 }
1570 
1571 static const struct action_ops snd_pcm_action_resume = {
1572 	.pre_action = snd_pcm_pre_resume,
1573 	.do_action = snd_pcm_do_resume,
1574 	.undo_action = snd_pcm_undo_resume,
1575 	.post_action = snd_pcm_post_resume
1576 };
1577 
1578 static int snd_pcm_resume(struct snd_pcm_substream *substream)
1579 {
1580 	return snd_pcm_action_lock_irq(&snd_pcm_action_resume, substream, 0);
1581 }
1582 
1583 #else
1584 
1585 static int snd_pcm_resume(struct snd_pcm_substream *substream)
1586 {
1587 	return -ENOSYS;
1588 }
1589 
1590 #endif /* CONFIG_PM */
1591 
1592 /*
1593  * xrun ioctl
1594  *
1595  * Change the RUNNING stream(s) to XRUN state.
1596  */
1597 static int snd_pcm_xrun(struct snd_pcm_substream *substream)
1598 {
1599 	struct snd_pcm_runtime *runtime = substream->runtime;
1600 	int result;
1601 
1602 	snd_pcm_stream_lock_irq(substream);
1603 	switch (runtime->status->state) {
1604 	case SNDRV_PCM_STATE_XRUN:
1605 		result = 0;	/* already there */
1606 		break;
1607 	case SNDRV_PCM_STATE_RUNNING:
1608 		__snd_pcm_xrun(substream);
1609 		result = 0;
1610 		break;
1611 	default:
1612 		result = -EBADFD;
1613 	}
1614 	snd_pcm_stream_unlock_irq(substream);
1615 	return result;
1616 }
1617 
1618 /*
1619  * reset ioctl
1620  */
1621 static int snd_pcm_pre_reset(struct snd_pcm_substream *substream, int state)
1622 {
1623 	struct snd_pcm_runtime *runtime = substream->runtime;
1624 	switch (runtime->status->state) {
1625 	case SNDRV_PCM_STATE_RUNNING:
1626 	case SNDRV_PCM_STATE_PREPARED:
1627 	case SNDRV_PCM_STATE_PAUSED:
1628 	case SNDRV_PCM_STATE_SUSPENDED:
1629 		return 0;
1630 	default:
1631 		return -EBADFD;
1632 	}
1633 }
1634 
1635 static int snd_pcm_do_reset(struct snd_pcm_substream *substream, int state)
1636 {
1637 	struct snd_pcm_runtime *runtime = substream->runtime;
1638 	int err = substream->ops->ioctl(substream, SNDRV_PCM_IOCTL1_RESET, NULL);
1639 	if (err < 0)
1640 		return err;
1641 	runtime->hw_ptr_base = 0;
1642 	runtime->hw_ptr_interrupt = runtime->status->hw_ptr -
1643 		runtime->status->hw_ptr % runtime->period_size;
1644 	runtime->silence_start = runtime->status->hw_ptr;
1645 	runtime->silence_filled = 0;
1646 	return 0;
1647 }
1648 
1649 static void snd_pcm_post_reset(struct snd_pcm_substream *substream, int state)
1650 {
1651 	struct snd_pcm_runtime *runtime = substream->runtime;
1652 	runtime->control->appl_ptr = runtime->status->hw_ptr;
1653 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
1654 	    runtime->silence_size > 0)
1655 		snd_pcm_playback_silence(substream, ULONG_MAX);
1656 }
1657 
1658 static const struct action_ops snd_pcm_action_reset = {
1659 	.pre_action = snd_pcm_pre_reset,
1660 	.do_action = snd_pcm_do_reset,
1661 	.post_action = snd_pcm_post_reset
1662 };
1663 
1664 static int snd_pcm_reset(struct snd_pcm_substream *substream)
1665 {
1666 	return snd_pcm_action_nonatomic(&snd_pcm_action_reset, substream, 0);
1667 }
1668 
1669 /*
1670  * prepare ioctl
1671  */
1672 /* we use the second argument for updating f_flags */
1673 static int snd_pcm_pre_prepare(struct snd_pcm_substream *substream,
1674 			       int f_flags)
1675 {
1676 	struct snd_pcm_runtime *runtime = substream->runtime;
1677 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN ||
1678 	    runtime->status->state == SNDRV_PCM_STATE_DISCONNECTED)
1679 		return -EBADFD;
1680 	if (snd_pcm_running(substream))
1681 		return -EBUSY;
1682 	substream->f_flags = f_flags;
1683 	return 0;
1684 }
1685 
1686 static int snd_pcm_do_prepare(struct snd_pcm_substream *substream, int state)
1687 {
1688 	int err;
1689 	err = substream->ops->prepare(substream);
1690 	if (err < 0)
1691 		return err;
1692 	return snd_pcm_do_reset(substream, 0);
1693 }
1694 
1695 static void snd_pcm_post_prepare(struct snd_pcm_substream *substream, int state)
1696 {
1697 	struct snd_pcm_runtime *runtime = substream->runtime;
1698 	runtime->control->appl_ptr = runtime->status->hw_ptr;
1699 	snd_pcm_set_state(substream, SNDRV_PCM_STATE_PREPARED);
1700 }
1701 
1702 static const struct action_ops snd_pcm_action_prepare = {
1703 	.pre_action = snd_pcm_pre_prepare,
1704 	.do_action = snd_pcm_do_prepare,
1705 	.post_action = snd_pcm_post_prepare
1706 };
1707 
1708 /**
1709  * snd_pcm_prepare - prepare the PCM substream to be triggerable
1710  * @substream: the PCM substream instance
1711  * @file: file to refer f_flags
1712  *
1713  * Return: Zero if successful, or a negative error code.
1714  */
1715 static int snd_pcm_prepare(struct snd_pcm_substream *substream,
1716 			   struct file *file)
1717 {
1718 	int f_flags;
1719 
1720 	if (file)
1721 		f_flags = file->f_flags;
1722 	else
1723 		f_flags = substream->f_flags;
1724 
1725 	snd_pcm_stream_lock_irq(substream);
1726 	switch (substream->runtime->status->state) {
1727 	case SNDRV_PCM_STATE_PAUSED:
1728 		snd_pcm_pause(substream, 0);
1729 		/* fallthru */
1730 	case SNDRV_PCM_STATE_SUSPENDED:
1731 		snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
1732 		break;
1733 	}
1734 	snd_pcm_stream_unlock_irq(substream);
1735 
1736 	return snd_pcm_action_nonatomic(&snd_pcm_action_prepare,
1737 					substream, f_flags);
1738 }
1739 
1740 /*
1741  * drain ioctl
1742  */
1743 
1744 static int snd_pcm_pre_drain_init(struct snd_pcm_substream *substream, int state)
1745 {
1746 	struct snd_pcm_runtime *runtime = substream->runtime;
1747 	switch (runtime->status->state) {
1748 	case SNDRV_PCM_STATE_OPEN:
1749 	case SNDRV_PCM_STATE_DISCONNECTED:
1750 	case SNDRV_PCM_STATE_SUSPENDED:
1751 		return -EBADFD;
1752 	}
1753 	runtime->trigger_master = substream;
1754 	return 0;
1755 }
1756 
1757 static int snd_pcm_do_drain_init(struct snd_pcm_substream *substream, int state)
1758 {
1759 	struct snd_pcm_runtime *runtime = substream->runtime;
1760 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
1761 		switch (runtime->status->state) {
1762 		case SNDRV_PCM_STATE_PREPARED:
1763 			/* start playback stream if possible */
1764 			if (! snd_pcm_playback_empty(substream)) {
1765 				snd_pcm_do_start(substream, SNDRV_PCM_STATE_DRAINING);
1766 				snd_pcm_post_start(substream, SNDRV_PCM_STATE_DRAINING);
1767 			} else {
1768 				runtime->status->state = SNDRV_PCM_STATE_SETUP;
1769 			}
1770 			break;
1771 		case SNDRV_PCM_STATE_RUNNING:
1772 			runtime->status->state = SNDRV_PCM_STATE_DRAINING;
1773 			break;
1774 		case SNDRV_PCM_STATE_XRUN:
1775 			runtime->status->state = SNDRV_PCM_STATE_SETUP;
1776 			break;
1777 		default:
1778 			break;
1779 		}
1780 	} else {
1781 		/* stop running stream */
1782 		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING) {
1783 			int new_state = snd_pcm_capture_avail(runtime) > 0 ?
1784 				SNDRV_PCM_STATE_DRAINING : SNDRV_PCM_STATE_SETUP;
1785 			snd_pcm_do_stop(substream, new_state);
1786 			snd_pcm_post_stop(substream, new_state);
1787 		}
1788 	}
1789 
1790 	if (runtime->status->state == SNDRV_PCM_STATE_DRAINING &&
1791 	    runtime->trigger_master == substream &&
1792 	    (runtime->hw.info & SNDRV_PCM_INFO_DRAIN_TRIGGER))
1793 		return substream->ops->trigger(substream,
1794 					       SNDRV_PCM_TRIGGER_DRAIN);
1795 
1796 	return 0;
1797 }
1798 
1799 static void snd_pcm_post_drain_init(struct snd_pcm_substream *substream, int state)
1800 {
1801 }
1802 
1803 static const struct action_ops snd_pcm_action_drain_init = {
1804 	.pre_action = snd_pcm_pre_drain_init,
1805 	.do_action = snd_pcm_do_drain_init,
1806 	.post_action = snd_pcm_post_drain_init
1807 };
1808 
1809 /*
1810  * Drain the stream(s).
1811  * When the substream is linked, sync until the draining of all playback streams
1812  * is finished.
1813  * After this call, all streams are supposed to be either SETUP or DRAINING
1814  * (capture only) state.
1815  */
1816 static int snd_pcm_drain(struct snd_pcm_substream *substream,
1817 			 struct file *file)
1818 {
1819 	struct snd_card *card;
1820 	struct snd_pcm_runtime *runtime;
1821 	struct snd_pcm_substream *s;
1822 	struct snd_pcm_group *group;
1823 	wait_queue_entry_t wait;
1824 	int result = 0;
1825 	int nonblock = 0;
1826 
1827 	card = substream->pcm->card;
1828 	runtime = substream->runtime;
1829 
1830 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1831 		return -EBADFD;
1832 
1833 	if (file) {
1834 		if (file->f_flags & O_NONBLOCK)
1835 			nonblock = 1;
1836 	} else if (substream->f_flags & O_NONBLOCK)
1837 		nonblock = 1;
1838 
1839 	snd_pcm_stream_lock_irq(substream);
1840 	/* resume pause */
1841 	if (runtime->status->state == SNDRV_PCM_STATE_PAUSED)
1842 		snd_pcm_pause(substream, 0);
1843 
1844 	/* pre-start/stop - all running streams are changed to DRAINING state */
1845 	result = snd_pcm_action(&snd_pcm_action_drain_init, substream, 0);
1846 	if (result < 0)
1847 		goto unlock;
1848 	/* in non-blocking, we don't wait in ioctl but let caller poll */
1849 	if (nonblock) {
1850 		result = -EAGAIN;
1851 		goto unlock;
1852 	}
1853 
1854 	for (;;) {
1855 		long tout;
1856 		struct snd_pcm_runtime *to_check;
1857 		if (signal_pending(current)) {
1858 			result = -ERESTARTSYS;
1859 			break;
1860 		}
1861 		/* find a substream to drain */
1862 		to_check = NULL;
1863 		group = snd_pcm_stream_group_ref(substream);
1864 		snd_pcm_group_for_each_entry(s, substream) {
1865 			if (s->stream != SNDRV_PCM_STREAM_PLAYBACK)
1866 				continue;
1867 			runtime = s->runtime;
1868 			if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
1869 				to_check = runtime;
1870 				break;
1871 			}
1872 		}
1873 		snd_pcm_group_unref(group, substream);
1874 		if (!to_check)
1875 			break; /* all drained */
1876 		init_waitqueue_entry(&wait, current);
1877 		add_wait_queue(&to_check->sleep, &wait);
1878 		snd_pcm_stream_unlock_irq(substream);
1879 		if (runtime->no_period_wakeup)
1880 			tout = MAX_SCHEDULE_TIMEOUT;
1881 		else {
1882 			tout = 10;
1883 			if (runtime->rate) {
1884 				long t = runtime->period_size * 2 / runtime->rate;
1885 				tout = max(t, tout);
1886 			}
1887 			tout = msecs_to_jiffies(tout * 1000);
1888 		}
1889 		tout = schedule_timeout_interruptible(tout);
1890 
1891 		snd_pcm_stream_lock_irq(substream);
1892 		group = snd_pcm_stream_group_ref(substream);
1893 		snd_pcm_group_for_each_entry(s, substream) {
1894 			if (s->runtime == to_check) {
1895 				remove_wait_queue(&to_check->sleep, &wait);
1896 				break;
1897 			}
1898 		}
1899 		snd_pcm_group_unref(group, substream);
1900 
1901 		if (card->shutdown) {
1902 			result = -ENODEV;
1903 			break;
1904 		}
1905 		if (tout == 0) {
1906 			if (substream->runtime->status->state == SNDRV_PCM_STATE_SUSPENDED)
1907 				result = -ESTRPIPE;
1908 			else {
1909 				dev_dbg(substream->pcm->card->dev,
1910 					"playback drain error (DMA or IRQ trouble?)\n");
1911 				snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
1912 				result = -EIO;
1913 			}
1914 			break;
1915 		}
1916 	}
1917 
1918  unlock:
1919 	snd_pcm_stream_unlock_irq(substream);
1920 
1921 	return result;
1922 }
1923 
1924 /*
1925  * drop ioctl
1926  *
1927  * Immediately put all linked substreams into SETUP state.
1928  */
1929 static int snd_pcm_drop(struct snd_pcm_substream *substream)
1930 {
1931 	struct snd_pcm_runtime *runtime;
1932 	int result = 0;
1933 
1934 	if (PCM_RUNTIME_CHECK(substream))
1935 		return -ENXIO;
1936 	runtime = substream->runtime;
1937 
1938 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN ||
1939 	    runtime->status->state == SNDRV_PCM_STATE_DISCONNECTED)
1940 		return -EBADFD;
1941 
1942 	snd_pcm_stream_lock_irq(substream);
1943 	/* resume pause */
1944 	if (runtime->status->state == SNDRV_PCM_STATE_PAUSED)
1945 		snd_pcm_pause(substream, 0);
1946 
1947 	snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
1948 	/* runtime->control->appl_ptr = runtime->status->hw_ptr; */
1949 	snd_pcm_stream_unlock_irq(substream);
1950 
1951 	return result;
1952 }
1953 
1954 
1955 static bool is_pcm_file(struct file *file)
1956 {
1957 	struct inode *inode = file_inode(file);
1958 	struct snd_pcm *pcm;
1959 	unsigned int minor;
1960 
1961 	if (!S_ISCHR(inode->i_mode) || imajor(inode) != snd_major)
1962 		return false;
1963 	minor = iminor(inode);
1964 	pcm = snd_lookup_minor_data(minor, SNDRV_DEVICE_TYPE_PCM_PLAYBACK);
1965 	if (!pcm)
1966 		pcm = snd_lookup_minor_data(minor, SNDRV_DEVICE_TYPE_PCM_CAPTURE);
1967 	if (!pcm)
1968 		return false;
1969 	snd_card_unref(pcm->card);
1970 	return true;
1971 }
1972 
1973 /*
1974  * PCM link handling
1975  */
1976 static int snd_pcm_link(struct snd_pcm_substream *substream, int fd)
1977 {
1978 	int res = 0;
1979 	struct snd_pcm_file *pcm_file;
1980 	struct snd_pcm_substream *substream1;
1981 	struct snd_pcm_group *group, *target_group;
1982 	bool nonatomic = substream->pcm->nonatomic;
1983 	struct fd f = fdget(fd);
1984 
1985 	if (!f.file)
1986 		return -EBADFD;
1987 	if (!is_pcm_file(f.file)) {
1988 		res = -EBADFD;
1989 		goto _badf;
1990 	}
1991 	pcm_file = f.file->private_data;
1992 	substream1 = pcm_file->substream;
1993 	group = kzalloc(sizeof(*group), GFP_KERNEL);
1994 	if (!group) {
1995 		res = -ENOMEM;
1996 		goto _nolock;
1997 	}
1998 	snd_pcm_group_init(group);
1999 
2000 	down_write(&snd_pcm_link_rwsem);
2001 	if (substream->runtime->status->state == SNDRV_PCM_STATE_OPEN ||
2002 	    substream->runtime->status->state != substream1->runtime->status->state ||
2003 	    substream->pcm->nonatomic != substream1->pcm->nonatomic) {
2004 		res = -EBADFD;
2005 		goto _end;
2006 	}
2007 	if (snd_pcm_stream_linked(substream1)) {
2008 		res = -EALREADY;
2009 		goto _end;
2010 	}
2011 
2012 	snd_pcm_stream_lock_irq(substream);
2013 	if (!snd_pcm_stream_linked(substream)) {
2014 		snd_pcm_group_assign(substream, group);
2015 		group = NULL; /* assigned, don't free this one below */
2016 	}
2017 	target_group = substream->group;
2018 	snd_pcm_stream_unlock_irq(substream);
2019 
2020 	snd_pcm_group_lock_irq(target_group, nonatomic);
2021 	snd_pcm_stream_lock(substream1);
2022 	snd_pcm_group_assign(substream1, target_group);
2023 	snd_pcm_stream_unlock(substream1);
2024 	snd_pcm_group_unlock_irq(target_group, nonatomic);
2025  _end:
2026 	up_write(&snd_pcm_link_rwsem);
2027  _nolock:
2028 	kfree(group);
2029  _badf:
2030 	fdput(f);
2031 	return res;
2032 }
2033 
2034 static void relink_to_local(struct snd_pcm_substream *substream)
2035 {
2036 	snd_pcm_stream_lock(substream);
2037 	snd_pcm_group_assign(substream, &substream->self_group);
2038 	snd_pcm_stream_unlock(substream);
2039 }
2040 
2041 static int snd_pcm_unlink(struct snd_pcm_substream *substream)
2042 {
2043 	struct snd_pcm_group *group;
2044 	bool nonatomic = substream->pcm->nonatomic;
2045 	bool do_free = false;
2046 	int res = 0;
2047 
2048 	down_write(&snd_pcm_link_rwsem);
2049 
2050 	if (!snd_pcm_stream_linked(substream)) {
2051 		res = -EALREADY;
2052 		goto _end;
2053 	}
2054 
2055 	group = substream->group;
2056 	snd_pcm_group_lock_irq(group, nonatomic);
2057 
2058 	relink_to_local(substream);
2059 
2060 	/* detach the last stream, too */
2061 	if (list_is_singular(&group->substreams)) {
2062 		relink_to_local(list_first_entry(&group->substreams,
2063 						 struct snd_pcm_substream,
2064 						 link_list));
2065 		do_free = !refcount_read(&group->refs);
2066 	}
2067 
2068 	snd_pcm_group_unlock_irq(group, nonatomic);
2069 	if (do_free)
2070 		kfree(group);
2071 
2072        _end:
2073 	up_write(&snd_pcm_link_rwsem);
2074 	return res;
2075 }
2076 
2077 /*
2078  * hw configurator
2079  */
2080 static int snd_pcm_hw_rule_mul(struct snd_pcm_hw_params *params,
2081 			       struct snd_pcm_hw_rule *rule)
2082 {
2083 	struct snd_interval t;
2084 	snd_interval_mul(hw_param_interval_c(params, rule->deps[0]),
2085 		     hw_param_interval_c(params, rule->deps[1]), &t);
2086 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2087 }
2088 
2089 static int snd_pcm_hw_rule_div(struct snd_pcm_hw_params *params,
2090 			       struct snd_pcm_hw_rule *rule)
2091 {
2092 	struct snd_interval t;
2093 	snd_interval_div(hw_param_interval_c(params, rule->deps[0]),
2094 		     hw_param_interval_c(params, rule->deps[1]), &t);
2095 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2096 }
2097 
2098 static int snd_pcm_hw_rule_muldivk(struct snd_pcm_hw_params *params,
2099 				   struct snd_pcm_hw_rule *rule)
2100 {
2101 	struct snd_interval t;
2102 	snd_interval_muldivk(hw_param_interval_c(params, rule->deps[0]),
2103 			 hw_param_interval_c(params, rule->deps[1]),
2104 			 (unsigned long) rule->private, &t);
2105 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2106 }
2107 
2108 static int snd_pcm_hw_rule_mulkdiv(struct snd_pcm_hw_params *params,
2109 				   struct snd_pcm_hw_rule *rule)
2110 {
2111 	struct snd_interval t;
2112 	snd_interval_mulkdiv(hw_param_interval_c(params, rule->deps[0]),
2113 			 (unsigned long) rule->private,
2114 			 hw_param_interval_c(params, rule->deps[1]), &t);
2115 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2116 }
2117 
2118 static int snd_pcm_hw_rule_format(struct snd_pcm_hw_params *params,
2119 				  struct snd_pcm_hw_rule *rule)
2120 {
2121 	unsigned int k;
2122 	const struct snd_interval *i =
2123 				hw_param_interval_c(params, rule->deps[0]);
2124 	struct snd_mask m;
2125 	struct snd_mask *mask = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
2126 	snd_mask_any(&m);
2127 	for (k = 0; k <= SNDRV_PCM_FORMAT_LAST; ++k) {
2128 		int bits;
2129 		if (! snd_mask_test(mask, k))
2130 			continue;
2131 		bits = snd_pcm_format_physical_width(k);
2132 		if (bits <= 0)
2133 			continue; /* ignore invalid formats */
2134 		if ((unsigned)bits < i->min || (unsigned)bits > i->max)
2135 			snd_mask_reset(&m, k);
2136 	}
2137 	return snd_mask_refine(mask, &m);
2138 }
2139 
2140 static int snd_pcm_hw_rule_sample_bits(struct snd_pcm_hw_params *params,
2141 				       struct snd_pcm_hw_rule *rule)
2142 {
2143 	struct snd_interval t;
2144 	unsigned int k;
2145 	t.min = UINT_MAX;
2146 	t.max = 0;
2147 	t.openmin = 0;
2148 	t.openmax = 0;
2149 	for (k = 0; k <= SNDRV_PCM_FORMAT_LAST; ++k) {
2150 		int bits;
2151 		if (! snd_mask_test(hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT), k))
2152 			continue;
2153 		bits = snd_pcm_format_physical_width(k);
2154 		if (bits <= 0)
2155 			continue; /* ignore invalid formats */
2156 		if (t.min > (unsigned)bits)
2157 			t.min = bits;
2158 		if (t.max < (unsigned)bits)
2159 			t.max = bits;
2160 	}
2161 	t.integer = 1;
2162 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2163 }
2164 
2165 #if SNDRV_PCM_RATE_5512 != 1 << 0 || SNDRV_PCM_RATE_192000 != 1 << 12
2166 #error "Change this table"
2167 #endif
2168 
2169 static const unsigned int rates[] = {
2170 	5512, 8000, 11025, 16000, 22050, 32000, 44100,
2171 	48000, 64000, 88200, 96000, 176400, 192000
2172 };
2173 
2174 const struct snd_pcm_hw_constraint_list snd_pcm_known_rates = {
2175 	.count = ARRAY_SIZE(rates),
2176 	.list = rates,
2177 };
2178 
2179 static int snd_pcm_hw_rule_rate(struct snd_pcm_hw_params *params,
2180 				struct snd_pcm_hw_rule *rule)
2181 {
2182 	struct snd_pcm_hardware *hw = rule->private;
2183 	return snd_interval_list(hw_param_interval(params, rule->var),
2184 				 snd_pcm_known_rates.count,
2185 				 snd_pcm_known_rates.list, hw->rates);
2186 }
2187 
2188 static int snd_pcm_hw_rule_buffer_bytes_max(struct snd_pcm_hw_params *params,
2189 					    struct snd_pcm_hw_rule *rule)
2190 {
2191 	struct snd_interval t;
2192 	struct snd_pcm_substream *substream = rule->private;
2193 	t.min = 0;
2194 	t.max = substream->buffer_bytes_max;
2195 	t.openmin = 0;
2196 	t.openmax = 0;
2197 	t.integer = 1;
2198 	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
2199 }
2200 
2201 int snd_pcm_hw_constraints_init(struct snd_pcm_substream *substream)
2202 {
2203 	struct snd_pcm_runtime *runtime = substream->runtime;
2204 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
2205 	int k, err;
2206 
2207 	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++) {
2208 		snd_mask_any(constrs_mask(constrs, k));
2209 	}
2210 
2211 	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++) {
2212 		snd_interval_any(constrs_interval(constrs, k));
2213 	}
2214 
2215 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_CHANNELS));
2216 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_BUFFER_SIZE));
2217 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_BUFFER_BYTES));
2218 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_SAMPLE_BITS));
2219 	snd_interval_setinteger(constrs_interval(constrs, SNDRV_PCM_HW_PARAM_FRAME_BITS));
2220 
2221 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
2222 				   snd_pcm_hw_rule_format, NULL,
2223 				   SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
2224 	if (err < 0)
2225 		return err;
2226 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
2227 				  snd_pcm_hw_rule_sample_bits, NULL,
2228 				  SNDRV_PCM_HW_PARAM_FORMAT,
2229 				  SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
2230 	if (err < 0)
2231 		return err;
2232 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
2233 				  snd_pcm_hw_rule_div, NULL,
2234 				  SNDRV_PCM_HW_PARAM_FRAME_BITS, SNDRV_PCM_HW_PARAM_CHANNELS, -1);
2235 	if (err < 0)
2236 		return err;
2237 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS,
2238 				  snd_pcm_hw_rule_mul, NULL,
2239 				  SNDRV_PCM_HW_PARAM_SAMPLE_BITS, SNDRV_PCM_HW_PARAM_CHANNELS, -1);
2240 	if (err < 0)
2241 		return err;
2242 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS,
2243 				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
2244 				  SNDRV_PCM_HW_PARAM_PERIOD_BYTES, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
2245 	if (err < 0)
2246 		return err;
2247 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FRAME_BITS,
2248 				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
2249 				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, -1);
2250 	if (err < 0)
2251 		return err;
2252 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
2253 				  snd_pcm_hw_rule_div, NULL,
2254 				  SNDRV_PCM_HW_PARAM_FRAME_BITS, SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
2255 	if (err < 0)
2256 		return err;
2257 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
2258 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2259 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_PERIOD_TIME, -1);
2260 	if (err < 0)
2261 		return err;
2262 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
2263 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2264 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_BUFFER_TIME, -1);
2265 	if (err < 0)
2266 		return err;
2267 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIODS,
2268 				  snd_pcm_hw_rule_div, NULL,
2269 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
2270 	if (err < 0)
2271 		return err;
2272 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
2273 				  snd_pcm_hw_rule_div, NULL,
2274 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_PERIODS, -1);
2275 	if (err < 0)
2276 		return err;
2277 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
2278 				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
2279 				  SNDRV_PCM_HW_PARAM_PERIOD_BYTES, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2280 	if (err < 0)
2281 		return err;
2282 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
2283 				  snd_pcm_hw_rule_muldivk, (void*) 1000000,
2284 				  SNDRV_PCM_HW_PARAM_PERIOD_TIME, SNDRV_PCM_HW_PARAM_RATE, -1);
2285 	if (err < 0)
2286 		return err;
2287 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
2288 				  snd_pcm_hw_rule_mul, NULL,
2289 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_PERIODS, -1);
2290 	if (err < 0)
2291 		return err;
2292 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
2293 				  snd_pcm_hw_rule_mulkdiv, (void*) 8,
2294 				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2295 	if (err < 0)
2296 		return err;
2297 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
2298 				  snd_pcm_hw_rule_muldivk, (void*) 1000000,
2299 				  SNDRV_PCM_HW_PARAM_BUFFER_TIME, SNDRV_PCM_HW_PARAM_RATE, -1);
2300 	if (err < 0)
2301 		return err;
2302 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
2303 				  snd_pcm_hw_rule_muldivk, (void*) 8,
2304 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2305 	if (err < 0)
2306 		return err;
2307 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
2308 				  snd_pcm_hw_rule_muldivk, (void*) 8,
2309 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_FRAME_BITS, -1);
2310 	if (err < 0)
2311 		return err;
2312 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
2313 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2314 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, SNDRV_PCM_HW_PARAM_RATE, -1);
2315 	if (err < 0)
2316 		return err;
2317 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_TIME,
2318 				  snd_pcm_hw_rule_mulkdiv, (void*) 1000000,
2319 				  SNDRV_PCM_HW_PARAM_BUFFER_SIZE, SNDRV_PCM_HW_PARAM_RATE, -1);
2320 	if (err < 0)
2321 		return err;
2322 	return 0;
2323 }
2324 
2325 int snd_pcm_hw_constraints_complete(struct snd_pcm_substream *substream)
2326 {
2327 	struct snd_pcm_runtime *runtime = substream->runtime;
2328 	struct snd_pcm_hardware *hw = &runtime->hw;
2329 	int err;
2330 	unsigned int mask = 0;
2331 
2332         if (hw->info & SNDRV_PCM_INFO_INTERLEAVED)
2333 		mask |= 1 << SNDRV_PCM_ACCESS_RW_INTERLEAVED;
2334         if (hw->info & SNDRV_PCM_INFO_NONINTERLEAVED)
2335 		mask |= 1 << SNDRV_PCM_ACCESS_RW_NONINTERLEAVED;
2336 	if (hw_support_mmap(substream)) {
2337 		if (hw->info & SNDRV_PCM_INFO_INTERLEAVED)
2338 			mask |= 1 << SNDRV_PCM_ACCESS_MMAP_INTERLEAVED;
2339 		if (hw->info & SNDRV_PCM_INFO_NONINTERLEAVED)
2340 			mask |= 1 << SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED;
2341 		if (hw->info & SNDRV_PCM_INFO_COMPLEX)
2342 			mask |= 1 << SNDRV_PCM_ACCESS_MMAP_COMPLEX;
2343 	}
2344 	err = snd_pcm_hw_constraint_mask(runtime, SNDRV_PCM_HW_PARAM_ACCESS, mask);
2345 	if (err < 0)
2346 		return err;
2347 
2348 	err = snd_pcm_hw_constraint_mask64(runtime, SNDRV_PCM_HW_PARAM_FORMAT, hw->formats);
2349 	if (err < 0)
2350 		return err;
2351 
2352 	err = snd_pcm_hw_constraint_mask(runtime, SNDRV_PCM_HW_PARAM_SUBFORMAT, 1 << SNDRV_PCM_SUBFORMAT_STD);
2353 	if (err < 0)
2354 		return err;
2355 
2356 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_CHANNELS,
2357 					   hw->channels_min, hw->channels_max);
2358 	if (err < 0)
2359 		return err;
2360 
2361 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_RATE,
2362 					   hw->rate_min, hw->rate_max);
2363 	if (err < 0)
2364 		return err;
2365 
2366 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
2367 					   hw->period_bytes_min, hw->period_bytes_max);
2368 	if (err < 0)
2369 		return err;
2370 
2371 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIODS,
2372 					   hw->periods_min, hw->periods_max);
2373 	if (err < 0)
2374 		return err;
2375 
2376 	err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
2377 					   hw->period_bytes_min, hw->buffer_bytes_max);
2378 	if (err < 0)
2379 		return err;
2380 
2381 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
2382 				  snd_pcm_hw_rule_buffer_bytes_max, substream,
2383 				  SNDRV_PCM_HW_PARAM_BUFFER_BYTES, -1);
2384 	if (err < 0)
2385 		return err;
2386 
2387 	/* FIXME: remove */
2388 	if (runtime->dma_bytes) {
2389 		err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 0, runtime->dma_bytes);
2390 		if (err < 0)
2391 			return err;
2392 	}
2393 
2394 	if (!(hw->rates & (SNDRV_PCM_RATE_KNOT | SNDRV_PCM_RATE_CONTINUOUS))) {
2395 		err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
2396 					  snd_pcm_hw_rule_rate, hw,
2397 					  SNDRV_PCM_HW_PARAM_RATE, -1);
2398 		if (err < 0)
2399 			return err;
2400 	}
2401 
2402 	/* FIXME: this belong to lowlevel */
2403 	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
2404 
2405 	return 0;
2406 }
2407 
2408 static void pcm_release_private(struct snd_pcm_substream *substream)
2409 {
2410 	if (snd_pcm_stream_linked(substream))
2411 		snd_pcm_unlink(substream);
2412 }
2413 
2414 void snd_pcm_release_substream(struct snd_pcm_substream *substream)
2415 {
2416 	substream->ref_count--;
2417 	if (substream->ref_count > 0)
2418 		return;
2419 
2420 	snd_pcm_drop(substream);
2421 	if (substream->hw_opened) {
2422 		if (substream->ops->hw_free &&
2423 		    substream->runtime->status->state != SNDRV_PCM_STATE_OPEN)
2424 			substream->ops->hw_free(substream);
2425 		substream->ops->close(substream);
2426 		substream->hw_opened = 0;
2427 	}
2428 	if (pm_qos_request_active(&substream->latency_pm_qos_req))
2429 		pm_qos_remove_request(&substream->latency_pm_qos_req);
2430 	if (substream->pcm_release) {
2431 		substream->pcm_release(substream);
2432 		substream->pcm_release = NULL;
2433 	}
2434 	snd_pcm_detach_substream(substream);
2435 }
2436 EXPORT_SYMBOL(snd_pcm_release_substream);
2437 
2438 int snd_pcm_open_substream(struct snd_pcm *pcm, int stream,
2439 			   struct file *file,
2440 			   struct snd_pcm_substream **rsubstream)
2441 {
2442 	struct snd_pcm_substream *substream;
2443 	int err;
2444 
2445 	err = snd_pcm_attach_substream(pcm, stream, file, &substream);
2446 	if (err < 0)
2447 		return err;
2448 	if (substream->ref_count > 1) {
2449 		*rsubstream = substream;
2450 		return 0;
2451 	}
2452 
2453 	err = snd_pcm_hw_constraints_init(substream);
2454 	if (err < 0) {
2455 		pcm_dbg(pcm, "snd_pcm_hw_constraints_init failed\n");
2456 		goto error;
2457 	}
2458 
2459 	if ((err = substream->ops->open(substream)) < 0)
2460 		goto error;
2461 
2462 	substream->hw_opened = 1;
2463 
2464 	err = snd_pcm_hw_constraints_complete(substream);
2465 	if (err < 0) {
2466 		pcm_dbg(pcm, "snd_pcm_hw_constraints_complete failed\n");
2467 		goto error;
2468 	}
2469 
2470 	*rsubstream = substream;
2471 	return 0;
2472 
2473  error:
2474 	snd_pcm_release_substream(substream);
2475 	return err;
2476 }
2477 EXPORT_SYMBOL(snd_pcm_open_substream);
2478 
2479 static int snd_pcm_open_file(struct file *file,
2480 			     struct snd_pcm *pcm,
2481 			     int stream)
2482 {
2483 	struct snd_pcm_file *pcm_file;
2484 	struct snd_pcm_substream *substream;
2485 	int err;
2486 
2487 	err = snd_pcm_open_substream(pcm, stream, file, &substream);
2488 	if (err < 0)
2489 		return err;
2490 
2491 	pcm_file = kzalloc(sizeof(*pcm_file), GFP_KERNEL);
2492 	if (pcm_file == NULL) {
2493 		snd_pcm_release_substream(substream);
2494 		return -ENOMEM;
2495 	}
2496 	pcm_file->substream = substream;
2497 	if (substream->ref_count == 1)
2498 		substream->pcm_release = pcm_release_private;
2499 	file->private_data = pcm_file;
2500 
2501 	return 0;
2502 }
2503 
2504 static int snd_pcm_playback_open(struct inode *inode, struct file *file)
2505 {
2506 	struct snd_pcm *pcm;
2507 	int err = nonseekable_open(inode, file);
2508 	if (err < 0)
2509 		return err;
2510 	pcm = snd_lookup_minor_data(iminor(inode),
2511 				    SNDRV_DEVICE_TYPE_PCM_PLAYBACK);
2512 	err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_PLAYBACK);
2513 	if (pcm)
2514 		snd_card_unref(pcm->card);
2515 	return err;
2516 }
2517 
2518 static int snd_pcm_capture_open(struct inode *inode, struct file *file)
2519 {
2520 	struct snd_pcm *pcm;
2521 	int err = nonseekable_open(inode, file);
2522 	if (err < 0)
2523 		return err;
2524 	pcm = snd_lookup_minor_data(iminor(inode),
2525 				    SNDRV_DEVICE_TYPE_PCM_CAPTURE);
2526 	err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_CAPTURE);
2527 	if (pcm)
2528 		snd_card_unref(pcm->card);
2529 	return err;
2530 }
2531 
2532 static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream)
2533 {
2534 	int err;
2535 	wait_queue_entry_t wait;
2536 
2537 	if (pcm == NULL) {
2538 		err = -ENODEV;
2539 		goto __error1;
2540 	}
2541 	err = snd_card_file_add(pcm->card, file);
2542 	if (err < 0)
2543 		goto __error1;
2544 	if (!try_module_get(pcm->card->module)) {
2545 		err = -EFAULT;
2546 		goto __error2;
2547 	}
2548 	init_waitqueue_entry(&wait, current);
2549 	add_wait_queue(&pcm->open_wait, &wait);
2550 	mutex_lock(&pcm->open_mutex);
2551 	while (1) {
2552 		err = snd_pcm_open_file(file, pcm, stream);
2553 		if (err >= 0)
2554 			break;
2555 		if (err == -EAGAIN) {
2556 			if (file->f_flags & O_NONBLOCK) {
2557 				err = -EBUSY;
2558 				break;
2559 			}
2560 		} else
2561 			break;
2562 		set_current_state(TASK_INTERRUPTIBLE);
2563 		mutex_unlock(&pcm->open_mutex);
2564 		schedule();
2565 		mutex_lock(&pcm->open_mutex);
2566 		if (pcm->card->shutdown) {
2567 			err = -ENODEV;
2568 			break;
2569 		}
2570 		if (signal_pending(current)) {
2571 			err = -ERESTARTSYS;
2572 			break;
2573 		}
2574 	}
2575 	remove_wait_queue(&pcm->open_wait, &wait);
2576 	mutex_unlock(&pcm->open_mutex);
2577 	if (err < 0)
2578 		goto __error;
2579 	return err;
2580 
2581       __error:
2582 	module_put(pcm->card->module);
2583       __error2:
2584       	snd_card_file_remove(pcm->card, file);
2585       __error1:
2586       	return err;
2587 }
2588 
2589 static int snd_pcm_release(struct inode *inode, struct file *file)
2590 {
2591 	struct snd_pcm *pcm;
2592 	struct snd_pcm_substream *substream;
2593 	struct snd_pcm_file *pcm_file;
2594 
2595 	pcm_file = file->private_data;
2596 	substream = pcm_file->substream;
2597 	if (snd_BUG_ON(!substream))
2598 		return -ENXIO;
2599 	pcm = substream->pcm;
2600 	mutex_lock(&pcm->open_mutex);
2601 	snd_pcm_release_substream(substream);
2602 	kfree(pcm_file);
2603 	mutex_unlock(&pcm->open_mutex);
2604 	wake_up(&pcm->open_wait);
2605 	module_put(pcm->card->module);
2606 	snd_card_file_remove(pcm->card, file);
2607 	return 0;
2608 }
2609 
2610 /* check and update PCM state; return 0 or a negative error
2611  * call this inside PCM lock
2612  */
2613 static int do_pcm_hwsync(struct snd_pcm_substream *substream)
2614 {
2615 	switch (substream->runtime->status->state) {
2616 	case SNDRV_PCM_STATE_DRAINING:
2617 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
2618 			return -EBADFD;
2619 		/* Fall through */
2620 	case SNDRV_PCM_STATE_RUNNING:
2621 		return snd_pcm_update_hw_ptr(substream);
2622 	case SNDRV_PCM_STATE_PREPARED:
2623 	case SNDRV_PCM_STATE_PAUSED:
2624 		return 0;
2625 	case SNDRV_PCM_STATE_SUSPENDED:
2626 		return -ESTRPIPE;
2627 	case SNDRV_PCM_STATE_XRUN:
2628 		return -EPIPE;
2629 	default:
2630 		return -EBADFD;
2631 	}
2632 }
2633 
2634 /* increase the appl_ptr; returns the processed frames or a negative error */
2635 static snd_pcm_sframes_t forward_appl_ptr(struct snd_pcm_substream *substream,
2636 					  snd_pcm_uframes_t frames,
2637 					   snd_pcm_sframes_t avail)
2638 {
2639 	struct snd_pcm_runtime *runtime = substream->runtime;
2640 	snd_pcm_sframes_t appl_ptr;
2641 	int ret;
2642 
2643 	if (avail <= 0)
2644 		return 0;
2645 	if (frames > (snd_pcm_uframes_t)avail)
2646 		frames = avail;
2647 	appl_ptr = runtime->control->appl_ptr + frames;
2648 	if (appl_ptr >= (snd_pcm_sframes_t)runtime->boundary)
2649 		appl_ptr -= runtime->boundary;
2650 	ret = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2651 	return ret < 0 ? ret : frames;
2652 }
2653 
2654 /* decrease the appl_ptr; returns the processed frames or zero for error */
2655 static snd_pcm_sframes_t rewind_appl_ptr(struct snd_pcm_substream *substream,
2656 					 snd_pcm_uframes_t frames,
2657 					 snd_pcm_sframes_t avail)
2658 {
2659 	struct snd_pcm_runtime *runtime = substream->runtime;
2660 	snd_pcm_sframes_t appl_ptr;
2661 	int ret;
2662 
2663 	if (avail <= 0)
2664 		return 0;
2665 	if (frames > (snd_pcm_uframes_t)avail)
2666 		frames = avail;
2667 	appl_ptr = runtime->control->appl_ptr - frames;
2668 	if (appl_ptr < 0)
2669 		appl_ptr += runtime->boundary;
2670 	ret = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2671 	/* NOTE: we return zero for errors because PulseAudio gets depressed
2672 	 * upon receiving an error from rewind ioctl and stops processing
2673 	 * any longer.  Returning zero means that no rewind is done, so
2674 	 * it's not absolutely wrong to answer like that.
2675 	 */
2676 	return ret < 0 ? 0 : frames;
2677 }
2678 
2679 static snd_pcm_sframes_t snd_pcm_rewind(struct snd_pcm_substream *substream,
2680 					snd_pcm_uframes_t frames)
2681 {
2682 	snd_pcm_sframes_t ret;
2683 
2684 	if (frames == 0)
2685 		return 0;
2686 
2687 	snd_pcm_stream_lock_irq(substream);
2688 	ret = do_pcm_hwsync(substream);
2689 	if (!ret)
2690 		ret = rewind_appl_ptr(substream, frames,
2691 				      snd_pcm_hw_avail(substream));
2692 	snd_pcm_stream_unlock_irq(substream);
2693 	return ret;
2694 }
2695 
2696 static snd_pcm_sframes_t snd_pcm_forward(struct snd_pcm_substream *substream,
2697 					 snd_pcm_uframes_t frames)
2698 {
2699 	snd_pcm_sframes_t ret;
2700 
2701 	if (frames == 0)
2702 		return 0;
2703 
2704 	snd_pcm_stream_lock_irq(substream);
2705 	ret = do_pcm_hwsync(substream);
2706 	if (!ret)
2707 		ret = forward_appl_ptr(substream, frames,
2708 				       snd_pcm_avail(substream));
2709 	snd_pcm_stream_unlock_irq(substream);
2710 	return ret;
2711 }
2712 
2713 static int snd_pcm_hwsync(struct snd_pcm_substream *substream)
2714 {
2715 	int err;
2716 
2717 	snd_pcm_stream_lock_irq(substream);
2718 	err = do_pcm_hwsync(substream);
2719 	snd_pcm_stream_unlock_irq(substream);
2720 	return err;
2721 }
2722 
2723 static int snd_pcm_delay(struct snd_pcm_substream *substream,
2724 			 snd_pcm_sframes_t *delay)
2725 {
2726 	int err;
2727 	snd_pcm_sframes_t n = 0;
2728 
2729 	snd_pcm_stream_lock_irq(substream);
2730 	err = do_pcm_hwsync(substream);
2731 	if (!err)
2732 		n = snd_pcm_calc_delay(substream);
2733 	snd_pcm_stream_unlock_irq(substream);
2734 	if (!err)
2735 		*delay = n;
2736 	return err;
2737 }
2738 
2739 static int snd_pcm_sync_ptr(struct snd_pcm_substream *substream,
2740 			    struct snd_pcm_sync_ptr __user *_sync_ptr)
2741 {
2742 	struct snd_pcm_runtime *runtime = substream->runtime;
2743 	struct snd_pcm_sync_ptr sync_ptr;
2744 	volatile struct snd_pcm_mmap_status *status;
2745 	volatile struct snd_pcm_mmap_control *control;
2746 	int err;
2747 
2748 	memset(&sync_ptr, 0, sizeof(sync_ptr));
2749 	if (get_user(sync_ptr.flags, (unsigned __user *)&(_sync_ptr->flags)))
2750 		return -EFAULT;
2751 	if (copy_from_user(&sync_ptr.c.control, &(_sync_ptr->c.control), sizeof(struct snd_pcm_mmap_control)))
2752 		return -EFAULT;
2753 	status = runtime->status;
2754 	control = runtime->control;
2755 	if (sync_ptr.flags & SNDRV_PCM_SYNC_PTR_HWSYNC) {
2756 		err = snd_pcm_hwsync(substream);
2757 		if (err < 0)
2758 			return err;
2759 	}
2760 	snd_pcm_stream_lock_irq(substream);
2761 	if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_APPL)) {
2762 		err = pcm_lib_apply_appl_ptr(substream,
2763 					     sync_ptr.c.control.appl_ptr);
2764 		if (err < 0) {
2765 			snd_pcm_stream_unlock_irq(substream);
2766 			return err;
2767 		}
2768 	} else {
2769 		sync_ptr.c.control.appl_ptr = control->appl_ptr;
2770 	}
2771 	if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_AVAIL_MIN))
2772 		control->avail_min = sync_ptr.c.control.avail_min;
2773 	else
2774 		sync_ptr.c.control.avail_min = control->avail_min;
2775 	sync_ptr.s.status.state = status->state;
2776 	sync_ptr.s.status.hw_ptr = status->hw_ptr;
2777 	sync_ptr.s.status.tstamp = status->tstamp;
2778 	sync_ptr.s.status.suspended_state = status->suspended_state;
2779 	sync_ptr.s.status.audio_tstamp = status->audio_tstamp;
2780 	snd_pcm_stream_unlock_irq(substream);
2781 	if (copy_to_user(_sync_ptr, &sync_ptr, sizeof(sync_ptr)))
2782 		return -EFAULT;
2783 	return 0;
2784 }
2785 
2786 static int snd_pcm_tstamp(struct snd_pcm_substream *substream, int __user *_arg)
2787 {
2788 	struct snd_pcm_runtime *runtime = substream->runtime;
2789 	int arg;
2790 
2791 	if (get_user(arg, _arg))
2792 		return -EFAULT;
2793 	if (arg < 0 || arg > SNDRV_PCM_TSTAMP_TYPE_LAST)
2794 		return -EINVAL;
2795 	runtime->tstamp_type = arg;
2796 	return 0;
2797 }
2798 
2799 static int snd_pcm_xferi_frames_ioctl(struct snd_pcm_substream *substream,
2800 				      struct snd_xferi __user *_xferi)
2801 {
2802 	struct snd_xferi xferi;
2803 	struct snd_pcm_runtime *runtime = substream->runtime;
2804 	snd_pcm_sframes_t result;
2805 
2806 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2807 		return -EBADFD;
2808 	if (put_user(0, &_xferi->result))
2809 		return -EFAULT;
2810 	if (copy_from_user(&xferi, _xferi, sizeof(xferi)))
2811 		return -EFAULT;
2812 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
2813 		result = snd_pcm_lib_write(substream, xferi.buf, xferi.frames);
2814 	else
2815 		result = snd_pcm_lib_read(substream, xferi.buf, xferi.frames);
2816 	__put_user(result, &_xferi->result);
2817 	return result < 0 ? result : 0;
2818 }
2819 
2820 static int snd_pcm_xfern_frames_ioctl(struct snd_pcm_substream *substream,
2821 				      struct snd_xfern __user *_xfern)
2822 {
2823 	struct snd_xfern xfern;
2824 	struct snd_pcm_runtime *runtime = substream->runtime;
2825 	void *bufs;
2826 	snd_pcm_sframes_t result;
2827 
2828 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2829 		return -EBADFD;
2830 	if (runtime->channels > 128)
2831 		return -EINVAL;
2832 	if (put_user(0, &_xfern->result))
2833 		return -EFAULT;
2834 	if (copy_from_user(&xfern, _xfern, sizeof(xfern)))
2835 		return -EFAULT;
2836 
2837 	bufs = memdup_user(xfern.bufs, sizeof(void *) * runtime->channels);
2838 	if (IS_ERR(bufs))
2839 		return PTR_ERR(bufs);
2840 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
2841 		result = snd_pcm_lib_writev(substream, bufs, xfern.frames);
2842 	else
2843 		result = snd_pcm_lib_readv(substream, bufs, xfern.frames);
2844 	kfree(bufs);
2845 	__put_user(result, &_xfern->result);
2846 	return result < 0 ? result : 0;
2847 }
2848 
2849 static int snd_pcm_rewind_ioctl(struct snd_pcm_substream *substream,
2850 				snd_pcm_uframes_t __user *_frames)
2851 {
2852 	snd_pcm_uframes_t frames;
2853 	snd_pcm_sframes_t result;
2854 
2855 	if (get_user(frames, _frames))
2856 		return -EFAULT;
2857 	if (put_user(0, _frames))
2858 		return -EFAULT;
2859 	result = snd_pcm_rewind(substream, frames);
2860 	__put_user(result, _frames);
2861 	return result < 0 ? result : 0;
2862 }
2863 
2864 static int snd_pcm_forward_ioctl(struct snd_pcm_substream *substream,
2865 				 snd_pcm_uframes_t __user *_frames)
2866 {
2867 	snd_pcm_uframes_t frames;
2868 	snd_pcm_sframes_t result;
2869 
2870 	if (get_user(frames, _frames))
2871 		return -EFAULT;
2872 	if (put_user(0, _frames))
2873 		return -EFAULT;
2874 	result = snd_pcm_forward(substream, frames);
2875 	__put_user(result, _frames);
2876 	return result < 0 ? result : 0;
2877 }
2878 
2879 static int snd_pcm_common_ioctl(struct file *file,
2880 				 struct snd_pcm_substream *substream,
2881 				 unsigned int cmd, void __user *arg)
2882 {
2883 	struct snd_pcm_file *pcm_file = file->private_data;
2884 	int res;
2885 
2886 	if (PCM_RUNTIME_CHECK(substream))
2887 		return -ENXIO;
2888 
2889 	res = snd_power_wait(substream->pcm->card, SNDRV_CTL_POWER_D0);
2890 	if (res < 0)
2891 		return res;
2892 
2893 	switch (cmd) {
2894 	case SNDRV_PCM_IOCTL_PVERSION:
2895 		return put_user(SNDRV_PCM_VERSION, (int __user *)arg) ? -EFAULT : 0;
2896 	case SNDRV_PCM_IOCTL_INFO:
2897 		return snd_pcm_info_user(substream, arg);
2898 	case SNDRV_PCM_IOCTL_TSTAMP:	/* just for compatibility */
2899 		return 0;
2900 	case SNDRV_PCM_IOCTL_TTSTAMP:
2901 		return snd_pcm_tstamp(substream, arg);
2902 	case SNDRV_PCM_IOCTL_USER_PVERSION:
2903 		if (get_user(pcm_file->user_pversion,
2904 			     (unsigned int __user *)arg))
2905 			return -EFAULT;
2906 		return 0;
2907 	case SNDRV_PCM_IOCTL_HW_REFINE:
2908 		return snd_pcm_hw_refine_user(substream, arg);
2909 	case SNDRV_PCM_IOCTL_HW_PARAMS:
2910 		return snd_pcm_hw_params_user(substream, arg);
2911 	case SNDRV_PCM_IOCTL_HW_FREE:
2912 		return snd_pcm_hw_free(substream);
2913 	case SNDRV_PCM_IOCTL_SW_PARAMS:
2914 		return snd_pcm_sw_params_user(substream, arg);
2915 	case SNDRV_PCM_IOCTL_STATUS:
2916 		return snd_pcm_status_user(substream, arg, false);
2917 	case SNDRV_PCM_IOCTL_STATUS_EXT:
2918 		return snd_pcm_status_user(substream, arg, true);
2919 	case SNDRV_PCM_IOCTL_CHANNEL_INFO:
2920 		return snd_pcm_channel_info_user(substream, arg);
2921 	case SNDRV_PCM_IOCTL_PREPARE:
2922 		return snd_pcm_prepare(substream, file);
2923 	case SNDRV_PCM_IOCTL_RESET:
2924 		return snd_pcm_reset(substream);
2925 	case SNDRV_PCM_IOCTL_START:
2926 		return snd_pcm_start_lock_irq(substream);
2927 	case SNDRV_PCM_IOCTL_LINK:
2928 		return snd_pcm_link(substream, (int)(unsigned long) arg);
2929 	case SNDRV_PCM_IOCTL_UNLINK:
2930 		return snd_pcm_unlink(substream);
2931 	case SNDRV_PCM_IOCTL_RESUME:
2932 		return snd_pcm_resume(substream);
2933 	case SNDRV_PCM_IOCTL_XRUN:
2934 		return snd_pcm_xrun(substream);
2935 	case SNDRV_PCM_IOCTL_HWSYNC:
2936 		return snd_pcm_hwsync(substream);
2937 	case SNDRV_PCM_IOCTL_DELAY:
2938 	{
2939 		snd_pcm_sframes_t delay;
2940 		snd_pcm_sframes_t __user *res = arg;
2941 		int err;
2942 
2943 		err = snd_pcm_delay(substream, &delay);
2944 		if (err)
2945 			return err;
2946 		if (put_user(delay, res))
2947 			return -EFAULT;
2948 		return 0;
2949 	}
2950 	case SNDRV_PCM_IOCTL_SYNC_PTR:
2951 		return snd_pcm_sync_ptr(substream, arg);
2952 #ifdef CONFIG_SND_SUPPORT_OLD_API
2953 	case SNDRV_PCM_IOCTL_HW_REFINE_OLD:
2954 		return snd_pcm_hw_refine_old_user(substream, arg);
2955 	case SNDRV_PCM_IOCTL_HW_PARAMS_OLD:
2956 		return snd_pcm_hw_params_old_user(substream, arg);
2957 #endif
2958 	case SNDRV_PCM_IOCTL_DRAIN:
2959 		return snd_pcm_drain(substream, file);
2960 	case SNDRV_PCM_IOCTL_DROP:
2961 		return snd_pcm_drop(substream);
2962 	case SNDRV_PCM_IOCTL_PAUSE:
2963 		return snd_pcm_action_lock_irq(&snd_pcm_action_pause,
2964 					       substream,
2965 					       (int)(unsigned long)arg);
2966 	case SNDRV_PCM_IOCTL_WRITEI_FRAMES:
2967 	case SNDRV_PCM_IOCTL_READI_FRAMES:
2968 		return snd_pcm_xferi_frames_ioctl(substream, arg);
2969 	case SNDRV_PCM_IOCTL_WRITEN_FRAMES:
2970 	case SNDRV_PCM_IOCTL_READN_FRAMES:
2971 		return snd_pcm_xfern_frames_ioctl(substream, arg);
2972 	case SNDRV_PCM_IOCTL_REWIND:
2973 		return snd_pcm_rewind_ioctl(substream, arg);
2974 	case SNDRV_PCM_IOCTL_FORWARD:
2975 		return snd_pcm_forward_ioctl(substream, arg);
2976 	}
2977 	pcm_dbg(substream->pcm, "unknown ioctl = 0x%x\n", cmd);
2978 	return -ENOTTY;
2979 }
2980 
2981 static long snd_pcm_ioctl(struct file *file, unsigned int cmd,
2982 			  unsigned long arg)
2983 {
2984 	struct snd_pcm_file *pcm_file;
2985 
2986 	pcm_file = file->private_data;
2987 
2988 	if (((cmd >> 8) & 0xff) != 'A')
2989 		return -ENOTTY;
2990 
2991 	return snd_pcm_common_ioctl(file, pcm_file->substream, cmd,
2992 				     (void __user *)arg);
2993 }
2994 
2995 /**
2996  * snd_pcm_kernel_ioctl - Execute PCM ioctl in the kernel-space
2997  * @substream: PCM substream
2998  * @cmd: IOCTL cmd
2999  * @arg: IOCTL argument
3000  *
3001  * The function is provided primarily for OSS layer and USB gadget drivers,
3002  * and it allows only the limited set of ioctls (hw_params, sw_params,
3003  * prepare, start, drain, drop, forward).
3004  */
3005 int snd_pcm_kernel_ioctl(struct snd_pcm_substream *substream,
3006 			 unsigned int cmd, void *arg)
3007 {
3008 	snd_pcm_uframes_t *frames = arg;
3009 	snd_pcm_sframes_t result;
3010 
3011 	switch (cmd) {
3012 	case SNDRV_PCM_IOCTL_FORWARD:
3013 	{
3014 		/* provided only for OSS; capture-only and no value returned */
3015 		if (substream->stream != SNDRV_PCM_STREAM_CAPTURE)
3016 			return -EINVAL;
3017 		result = snd_pcm_forward(substream, *frames);
3018 		return result < 0 ? result : 0;
3019 	}
3020 	case SNDRV_PCM_IOCTL_HW_PARAMS:
3021 		return snd_pcm_hw_params(substream, arg);
3022 	case SNDRV_PCM_IOCTL_SW_PARAMS:
3023 		return snd_pcm_sw_params(substream, arg);
3024 	case SNDRV_PCM_IOCTL_PREPARE:
3025 		return snd_pcm_prepare(substream, NULL);
3026 	case SNDRV_PCM_IOCTL_START:
3027 		return snd_pcm_start_lock_irq(substream);
3028 	case SNDRV_PCM_IOCTL_DRAIN:
3029 		return snd_pcm_drain(substream, NULL);
3030 	case SNDRV_PCM_IOCTL_DROP:
3031 		return snd_pcm_drop(substream);
3032 	case SNDRV_PCM_IOCTL_DELAY:
3033 		return snd_pcm_delay(substream, frames);
3034 	default:
3035 		return -EINVAL;
3036 	}
3037 }
3038 EXPORT_SYMBOL(snd_pcm_kernel_ioctl);
3039 
3040 static ssize_t snd_pcm_read(struct file *file, char __user *buf, size_t count,
3041 			    loff_t * offset)
3042 {
3043 	struct snd_pcm_file *pcm_file;
3044 	struct snd_pcm_substream *substream;
3045 	struct snd_pcm_runtime *runtime;
3046 	snd_pcm_sframes_t result;
3047 
3048 	pcm_file = file->private_data;
3049 	substream = pcm_file->substream;
3050 	if (PCM_RUNTIME_CHECK(substream))
3051 		return -ENXIO;
3052 	runtime = substream->runtime;
3053 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3054 		return -EBADFD;
3055 	if (!frame_aligned(runtime, count))
3056 		return -EINVAL;
3057 	count = bytes_to_frames(runtime, count);
3058 	result = snd_pcm_lib_read(substream, buf, count);
3059 	if (result > 0)
3060 		result = frames_to_bytes(runtime, result);
3061 	return result;
3062 }
3063 
3064 static ssize_t snd_pcm_write(struct file *file, const char __user *buf,
3065 			     size_t count, loff_t * offset)
3066 {
3067 	struct snd_pcm_file *pcm_file;
3068 	struct snd_pcm_substream *substream;
3069 	struct snd_pcm_runtime *runtime;
3070 	snd_pcm_sframes_t result;
3071 
3072 	pcm_file = file->private_data;
3073 	substream = pcm_file->substream;
3074 	if (PCM_RUNTIME_CHECK(substream))
3075 		return -ENXIO;
3076 	runtime = substream->runtime;
3077 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3078 		return -EBADFD;
3079 	if (!frame_aligned(runtime, count))
3080 		return -EINVAL;
3081 	count = bytes_to_frames(runtime, count);
3082 	result = snd_pcm_lib_write(substream, buf, count);
3083 	if (result > 0)
3084 		result = frames_to_bytes(runtime, result);
3085 	return result;
3086 }
3087 
3088 static ssize_t snd_pcm_readv(struct kiocb *iocb, struct iov_iter *to)
3089 {
3090 	struct snd_pcm_file *pcm_file;
3091 	struct snd_pcm_substream *substream;
3092 	struct snd_pcm_runtime *runtime;
3093 	snd_pcm_sframes_t result;
3094 	unsigned long i;
3095 	void __user **bufs;
3096 	snd_pcm_uframes_t frames;
3097 
3098 	pcm_file = iocb->ki_filp->private_data;
3099 	substream = pcm_file->substream;
3100 	if (PCM_RUNTIME_CHECK(substream))
3101 		return -ENXIO;
3102 	runtime = substream->runtime;
3103 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3104 		return -EBADFD;
3105 	if (!iter_is_iovec(to))
3106 		return -EINVAL;
3107 	if (to->nr_segs > 1024 || to->nr_segs != runtime->channels)
3108 		return -EINVAL;
3109 	if (!frame_aligned(runtime, to->iov->iov_len))
3110 		return -EINVAL;
3111 	frames = bytes_to_samples(runtime, to->iov->iov_len);
3112 	bufs = kmalloc_array(to->nr_segs, sizeof(void *), GFP_KERNEL);
3113 	if (bufs == NULL)
3114 		return -ENOMEM;
3115 	for (i = 0; i < to->nr_segs; ++i)
3116 		bufs[i] = to->iov[i].iov_base;
3117 	result = snd_pcm_lib_readv(substream, bufs, frames);
3118 	if (result > 0)
3119 		result = frames_to_bytes(runtime, result);
3120 	kfree(bufs);
3121 	return result;
3122 }
3123 
3124 static ssize_t snd_pcm_writev(struct kiocb *iocb, struct iov_iter *from)
3125 {
3126 	struct snd_pcm_file *pcm_file;
3127 	struct snd_pcm_substream *substream;
3128 	struct snd_pcm_runtime *runtime;
3129 	snd_pcm_sframes_t result;
3130 	unsigned long i;
3131 	void __user **bufs;
3132 	snd_pcm_uframes_t frames;
3133 
3134 	pcm_file = iocb->ki_filp->private_data;
3135 	substream = pcm_file->substream;
3136 	if (PCM_RUNTIME_CHECK(substream))
3137 		return -ENXIO;
3138 	runtime = substream->runtime;
3139 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3140 		return -EBADFD;
3141 	if (!iter_is_iovec(from))
3142 		return -EINVAL;
3143 	if (from->nr_segs > 128 || from->nr_segs != runtime->channels ||
3144 	    !frame_aligned(runtime, from->iov->iov_len))
3145 		return -EINVAL;
3146 	frames = bytes_to_samples(runtime, from->iov->iov_len);
3147 	bufs = kmalloc_array(from->nr_segs, sizeof(void *), GFP_KERNEL);
3148 	if (bufs == NULL)
3149 		return -ENOMEM;
3150 	for (i = 0; i < from->nr_segs; ++i)
3151 		bufs[i] = from->iov[i].iov_base;
3152 	result = snd_pcm_lib_writev(substream, bufs, frames);
3153 	if (result > 0)
3154 		result = frames_to_bytes(runtime, result);
3155 	kfree(bufs);
3156 	return result;
3157 }
3158 
3159 static __poll_t snd_pcm_poll(struct file *file, poll_table *wait)
3160 {
3161 	struct snd_pcm_file *pcm_file;
3162 	struct snd_pcm_substream *substream;
3163 	struct snd_pcm_runtime *runtime;
3164 	__poll_t mask, ok;
3165 	snd_pcm_uframes_t avail;
3166 
3167 	pcm_file = file->private_data;
3168 
3169 	substream = pcm_file->substream;
3170 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
3171 		ok = EPOLLOUT | EPOLLWRNORM;
3172 	else
3173 		ok = EPOLLIN | EPOLLRDNORM;
3174 	if (PCM_RUNTIME_CHECK(substream))
3175 		return ok | EPOLLERR;
3176 
3177 	runtime = substream->runtime;
3178 	poll_wait(file, &runtime->sleep, wait);
3179 
3180 	mask = 0;
3181 	snd_pcm_stream_lock_irq(substream);
3182 	avail = snd_pcm_avail(substream);
3183 	switch (runtime->status->state) {
3184 	case SNDRV_PCM_STATE_RUNNING:
3185 	case SNDRV_PCM_STATE_PREPARED:
3186 	case SNDRV_PCM_STATE_PAUSED:
3187 		if (avail >= runtime->control->avail_min)
3188 			mask = ok;
3189 		break;
3190 	case SNDRV_PCM_STATE_DRAINING:
3191 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
3192 			mask = ok;
3193 			if (!avail)
3194 				mask |= EPOLLERR;
3195 		}
3196 		break;
3197 	default:
3198 		mask = ok | EPOLLERR;
3199 		break;
3200 	}
3201 	snd_pcm_stream_unlock_irq(substream);
3202 	return mask;
3203 }
3204 
3205 /*
3206  * mmap support
3207  */
3208 
3209 /*
3210  * Only on coherent architectures, we can mmap the status and the control records
3211  * for effcient data transfer.  On others, we have to use HWSYNC ioctl...
3212  */
3213 #if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_ALPHA)
3214 /*
3215  * mmap status record
3216  */
3217 static vm_fault_t snd_pcm_mmap_status_fault(struct vm_fault *vmf)
3218 {
3219 	struct snd_pcm_substream *substream = vmf->vma->vm_private_data;
3220 	struct snd_pcm_runtime *runtime;
3221 
3222 	if (substream == NULL)
3223 		return VM_FAULT_SIGBUS;
3224 	runtime = substream->runtime;
3225 	vmf->page = virt_to_page(runtime->status);
3226 	get_page(vmf->page);
3227 	return 0;
3228 }
3229 
3230 static const struct vm_operations_struct snd_pcm_vm_ops_status =
3231 {
3232 	.fault =	snd_pcm_mmap_status_fault,
3233 };
3234 
3235 static int snd_pcm_mmap_status(struct snd_pcm_substream *substream, struct file *file,
3236 			       struct vm_area_struct *area)
3237 {
3238 	long size;
3239 	if (!(area->vm_flags & VM_READ))
3240 		return -EINVAL;
3241 	size = area->vm_end - area->vm_start;
3242 	if (size != PAGE_ALIGN(sizeof(struct snd_pcm_mmap_status)))
3243 		return -EINVAL;
3244 	area->vm_ops = &snd_pcm_vm_ops_status;
3245 	area->vm_private_data = substream;
3246 	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
3247 	return 0;
3248 }
3249 
3250 /*
3251  * mmap control record
3252  */
3253 static vm_fault_t snd_pcm_mmap_control_fault(struct vm_fault *vmf)
3254 {
3255 	struct snd_pcm_substream *substream = vmf->vma->vm_private_data;
3256 	struct snd_pcm_runtime *runtime;
3257 
3258 	if (substream == NULL)
3259 		return VM_FAULT_SIGBUS;
3260 	runtime = substream->runtime;
3261 	vmf->page = virt_to_page(runtime->control);
3262 	get_page(vmf->page);
3263 	return 0;
3264 }
3265 
3266 static const struct vm_operations_struct snd_pcm_vm_ops_control =
3267 {
3268 	.fault =	snd_pcm_mmap_control_fault,
3269 };
3270 
3271 static int snd_pcm_mmap_control(struct snd_pcm_substream *substream, struct file *file,
3272 				struct vm_area_struct *area)
3273 {
3274 	long size;
3275 	if (!(area->vm_flags & VM_READ))
3276 		return -EINVAL;
3277 	size = area->vm_end - area->vm_start;
3278 	if (size != PAGE_ALIGN(sizeof(struct snd_pcm_mmap_control)))
3279 		return -EINVAL;
3280 	area->vm_ops = &snd_pcm_vm_ops_control;
3281 	area->vm_private_data = substream;
3282 	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
3283 	return 0;
3284 }
3285 
3286 static bool pcm_status_mmap_allowed(struct snd_pcm_file *pcm_file)
3287 {
3288 	if (pcm_file->no_compat_mmap)
3289 		return false;
3290 	/* See pcm_control_mmap_allowed() below.
3291 	 * Since older alsa-lib requires both status and control mmaps to be
3292 	 * coupled, we have to disable the status mmap for old alsa-lib, too.
3293 	 */
3294 	if (pcm_file->user_pversion < SNDRV_PROTOCOL_VERSION(2, 0, 14) &&
3295 	    (pcm_file->substream->runtime->hw.info & SNDRV_PCM_INFO_SYNC_APPLPTR))
3296 		return false;
3297 	return true;
3298 }
3299 
3300 static bool pcm_control_mmap_allowed(struct snd_pcm_file *pcm_file)
3301 {
3302 	if (pcm_file->no_compat_mmap)
3303 		return false;
3304 	/* Disallow the control mmap when SYNC_APPLPTR flag is set;
3305 	 * it enforces the user-space to fall back to snd_pcm_sync_ptr(),
3306 	 * thus it effectively assures the manual update of appl_ptr.
3307 	 */
3308 	if (pcm_file->substream->runtime->hw.info & SNDRV_PCM_INFO_SYNC_APPLPTR)
3309 		return false;
3310 	return true;
3311 }
3312 
3313 #else /* ! coherent mmap */
3314 /*
3315  * don't support mmap for status and control records.
3316  */
3317 #define pcm_status_mmap_allowed(pcm_file)	false
3318 #define pcm_control_mmap_allowed(pcm_file)	false
3319 
3320 static int snd_pcm_mmap_status(struct snd_pcm_substream *substream, struct file *file,
3321 			       struct vm_area_struct *area)
3322 {
3323 	return -ENXIO;
3324 }
3325 static int snd_pcm_mmap_control(struct snd_pcm_substream *substream, struct file *file,
3326 				struct vm_area_struct *area)
3327 {
3328 	return -ENXIO;
3329 }
3330 #endif /* coherent mmap */
3331 
3332 static inline struct page *
3333 snd_pcm_default_page_ops(struct snd_pcm_substream *substream, unsigned long ofs)
3334 {
3335 	void *vaddr = substream->runtime->dma_area + ofs;
3336 	return virt_to_page(vaddr);
3337 }
3338 
3339 /*
3340  * fault callback for mmapping a RAM page
3341  */
3342 static vm_fault_t snd_pcm_mmap_data_fault(struct vm_fault *vmf)
3343 {
3344 	struct snd_pcm_substream *substream = vmf->vma->vm_private_data;
3345 	struct snd_pcm_runtime *runtime;
3346 	unsigned long offset;
3347 	struct page * page;
3348 	size_t dma_bytes;
3349 
3350 	if (substream == NULL)
3351 		return VM_FAULT_SIGBUS;
3352 	runtime = substream->runtime;
3353 	offset = vmf->pgoff << PAGE_SHIFT;
3354 	dma_bytes = PAGE_ALIGN(runtime->dma_bytes);
3355 	if (offset > dma_bytes - PAGE_SIZE)
3356 		return VM_FAULT_SIGBUS;
3357 	if (substream->ops->page)
3358 		page = substream->ops->page(substream, offset);
3359 	else
3360 		page = snd_pcm_default_page_ops(substream, offset);
3361 	if (!page)
3362 		return VM_FAULT_SIGBUS;
3363 	get_page(page);
3364 	vmf->page = page;
3365 	return 0;
3366 }
3367 
3368 static const struct vm_operations_struct snd_pcm_vm_ops_data = {
3369 	.open =		snd_pcm_mmap_data_open,
3370 	.close =	snd_pcm_mmap_data_close,
3371 };
3372 
3373 static const struct vm_operations_struct snd_pcm_vm_ops_data_fault = {
3374 	.open =		snd_pcm_mmap_data_open,
3375 	.close =	snd_pcm_mmap_data_close,
3376 	.fault =	snd_pcm_mmap_data_fault,
3377 };
3378 
3379 /*
3380  * mmap the DMA buffer on RAM
3381  */
3382 
3383 /**
3384  * snd_pcm_lib_default_mmap - Default PCM data mmap function
3385  * @substream: PCM substream
3386  * @area: VMA
3387  *
3388  * This is the default mmap handler for PCM data.  When mmap pcm_ops is NULL,
3389  * this function is invoked implicitly.
3390  */
3391 int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
3392 			     struct vm_area_struct *area)
3393 {
3394 	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
3395 #ifdef CONFIG_GENERIC_ALLOCATOR
3396 	if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV_IRAM) {
3397 		area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
3398 		return remap_pfn_range(area, area->vm_start,
3399 				substream->dma_buffer.addr >> PAGE_SHIFT,
3400 				area->vm_end - area->vm_start, area->vm_page_prot);
3401 	}
3402 #endif /* CONFIG_GENERIC_ALLOCATOR */
3403 #ifndef CONFIG_X86 /* for avoiding warnings arch/x86/mm/pat.c */
3404 	if (IS_ENABLED(CONFIG_HAS_DMA) && !substream->ops->page &&
3405 	    substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV)
3406 		return dma_mmap_coherent(substream->dma_buffer.dev.dev,
3407 					 area,
3408 					 substream->runtime->dma_area,
3409 					 substream->runtime->dma_addr,
3410 					 substream->runtime->dma_bytes);
3411 #endif /* CONFIG_X86 */
3412 	/* mmap with fault handler */
3413 	area->vm_ops = &snd_pcm_vm_ops_data_fault;
3414 	return 0;
3415 }
3416 EXPORT_SYMBOL_GPL(snd_pcm_lib_default_mmap);
3417 
3418 /*
3419  * mmap the DMA buffer on I/O memory area
3420  */
3421 #if SNDRV_PCM_INFO_MMAP_IOMEM
3422 /**
3423  * snd_pcm_lib_mmap_iomem - Default PCM data mmap function for I/O mem
3424  * @substream: PCM substream
3425  * @area: VMA
3426  *
3427  * When your hardware uses the iomapped pages as the hardware buffer and
3428  * wants to mmap it, pass this function as mmap pcm_ops.  Note that this
3429  * is supposed to work only on limited architectures.
3430  */
3431 int snd_pcm_lib_mmap_iomem(struct snd_pcm_substream *substream,
3432 			   struct vm_area_struct *area)
3433 {
3434 	struct snd_pcm_runtime *runtime = substream->runtime;
3435 
3436 	area->vm_page_prot = pgprot_noncached(area->vm_page_prot);
3437 	return vm_iomap_memory(area, runtime->dma_addr, runtime->dma_bytes);
3438 }
3439 EXPORT_SYMBOL(snd_pcm_lib_mmap_iomem);
3440 #endif /* SNDRV_PCM_INFO_MMAP */
3441 
3442 /*
3443  * mmap DMA buffer
3444  */
3445 int snd_pcm_mmap_data(struct snd_pcm_substream *substream, struct file *file,
3446 		      struct vm_area_struct *area)
3447 {
3448 	struct snd_pcm_runtime *runtime;
3449 	long size;
3450 	unsigned long offset;
3451 	size_t dma_bytes;
3452 	int err;
3453 
3454 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
3455 		if (!(area->vm_flags & (VM_WRITE|VM_READ)))
3456 			return -EINVAL;
3457 	} else {
3458 		if (!(area->vm_flags & VM_READ))
3459 			return -EINVAL;
3460 	}
3461 	runtime = substream->runtime;
3462 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
3463 		return -EBADFD;
3464 	if (!(runtime->info & SNDRV_PCM_INFO_MMAP))
3465 		return -ENXIO;
3466 	if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
3467 	    runtime->access == SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
3468 		return -EINVAL;
3469 	size = area->vm_end - area->vm_start;
3470 	offset = area->vm_pgoff << PAGE_SHIFT;
3471 	dma_bytes = PAGE_ALIGN(runtime->dma_bytes);
3472 	if ((size_t)size > dma_bytes)
3473 		return -EINVAL;
3474 	if (offset > dma_bytes - size)
3475 		return -EINVAL;
3476 
3477 	area->vm_ops = &snd_pcm_vm_ops_data;
3478 	area->vm_private_data = substream;
3479 	if (substream->ops->mmap)
3480 		err = substream->ops->mmap(substream, area);
3481 	else
3482 		err = snd_pcm_lib_default_mmap(substream, area);
3483 	if (!err)
3484 		atomic_inc(&substream->mmap_count);
3485 	return err;
3486 }
3487 EXPORT_SYMBOL(snd_pcm_mmap_data);
3488 
3489 static int snd_pcm_mmap(struct file *file, struct vm_area_struct *area)
3490 {
3491 	struct snd_pcm_file * pcm_file;
3492 	struct snd_pcm_substream *substream;
3493 	unsigned long offset;
3494 
3495 	pcm_file = file->private_data;
3496 	substream = pcm_file->substream;
3497 	if (PCM_RUNTIME_CHECK(substream))
3498 		return -ENXIO;
3499 
3500 	offset = area->vm_pgoff << PAGE_SHIFT;
3501 	switch (offset) {
3502 	case SNDRV_PCM_MMAP_OFFSET_STATUS:
3503 		if (!pcm_status_mmap_allowed(pcm_file))
3504 			return -ENXIO;
3505 		return snd_pcm_mmap_status(substream, file, area);
3506 	case SNDRV_PCM_MMAP_OFFSET_CONTROL:
3507 		if (!pcm_control_mmap_allowed(pcm_file))
3508 			return -ENXIO;
3509 		return snd_pcm_mmap_control(substream, file, area);
3510 	default:
3511 		return snd_pcm_mmap_data(substream, file, area);
3512 	}
3513 	return 0;
3514 }
3515 
3516 static int snd_pcm_fasync(int fd, struct file * file, int on)
3517 {
3518 	struct snd_pcm_file * pcm_file;
3519 	struct snd_pcm_substream *substream;
3520 	struct snd_pcm_runtime *runtime;
3521 
3522 	pcm_file = file->private_data;
3523 	substream = pcm_file->substream;
3524 	if (PCM_RUNTIME_CHECK(substream))
3525 		return -ENXIO;
3526 	runtime = substream->runtime;
3527 	return fasync_helper(fd, file, on, &runtime->fasync);
3528 }
3529 
3530 /*
3531  * ioctl32 compat
3532  */
3533 #ifdef CONFIG_COMPAT
3534 #include "pcm_compat.c"
3535 #else
3536 #define snd_pcm_ioctl_compat	NULL
3537 #endif
3538 
3539 /*
3540  *  To be removed helpers to keep binary compatibility
3541  */
3542 
3543 #ifdef CONFIG_SND_SUPPORT_OLD_API
3544 #define __OLD_TO_NEW_MASK(x) ((x&7)|((x&0x07fffff8)<<5))
3545 #define __NEW_TO_OLD_MASK(x) ((x&7)|((x&0xffffff00)>>5))
3546 
3547 static void snd_pcm_hw_convert_from_old_params(struct snd_pcm_hw_params *params,
3548 					       struct snd_pcm_hw_params_old *oparams)
3549 {
3550 	unsigned int i;
3551 
3552 	memset(params, 0, sizeof(*params));
3553 	params->flags = oparams->flags;
3554 	for (i = 0; i < ARRAY_SIZE(oparams->masks); i++)
3555 		params->masks[i].bits[0] = oparams->masks[i];
3556 	memcpy(params->intervals, oparams->intervals, sizeof(oparams->intervals));
3557 	params->rmask = __OLD_TO_NEW_MASK(oparams->rmask);
3558 	params->cmask = __OLD_TO_NEW_MASK(oparams->cmask);
3559 	params->info = oparams->info;
3560 	params->msbits = oparams->msbits;
3561 	params->rate_num = oparams->rate_num;
3562 	params->rate_den = oparams->rate_den;
3563 	params->fifo_size = oparams->fifo_size;
3564 }
3565 
3566 static void snd_pcm_hw_convert_to_old_params(struct snd_pcm_hw_params_old *oparams,
3567 					     struct snd_pcm_hw_params *params)
3568 {
3569 	unsigned int i;
3570 
3571 	memset(oparams, 0, sizeof(*oparams));
3572 	oparams->flags = params->flags;
3573 	for (i = 0; i < ARRAY_SIZE(oparams->masks); i++)
3574 		oparams->masks[i] = params->masks[i].bits[0];
3575 	memcpy(oparams->intervals, params->intervals, sizeof(oparams->intervals));
3576 	oparams->rmask = __NEW_TO_OLD_MASK(params->rmask);
3577 	oparams->cmask = __NEW_TO_OLD_MASK(params->cmask);
3578 	oparams->info = params->info;
3579 	oparams->msbits = params->msbits;
3580 	oparams->rate_num = params->rate_num;
3581 	oparams->rate_den = params->rate_den;
3582 	oparams->fifo_size = params->fifo_size;
3583 }
3584 
3585 static int snd_pcm_hw_refine_old_user(struct snd_pcm_substream *substream,
3586 				      struct snd_pcm_hw_params_old __user * _oparams)
3587 {
3588 	struct snd_pcm_hw_params *params;
3589 	struct snd_pcm_hw_params_old *oparams = NULL;
3590 	int err;
3591 
3592 	params = kmalloc(sizeof(*params), GFP_KERNEL);
3593 	if (!params)
3594 		return -ENOMEM;
3595 
3596 	oparams = memdup_user(_oparams, sizeof(*oparams));
3597 	if (IS_ERR(oparams)) {
3598 		err = PTR_ERR(oparams);
3599 		goto out;
3600 	}
3601 	snd_pcm_hw_convert_from_old_params(params, oparams);
3602 	err = snd_pcm_hw_refine(substream, params);
3603 	if (err < 0)
3604 		goto out_old;
3605 
3606 	err = fixup_unreferenced_params(substream, params);
3607 	if (err < 0)
3608 		goto out_old;
3609 
3610 	snd_pcm_hw_convert_to_old_params(oparams, params);
3611 	if (copy_to_user(_oparams, oparams, sizeof(*oparams)))
3612 		err = -EFAULT;
3613 out_old:
3614 	kfree(oparams);
3615 out:
3616 	kfree(params);
3617 	return err;
3618 }
3619 
3620 static int snd_pcm_hw_params_old_user(struct snd_pcm_substream *substream,
3621 				      struct snd_pcm_hw_params_old __user * _oparams)
3622 {
3623 	struct snd_pcm_hw_params *params;
3624 	struct snd_pcm_hw_params_old *oparams = NULL;
3625 	int err;
3626 
3627 	params = kmalloc(sizeof(*params), GFP_KERNEL);
3628 	if (!params)
3629 		return -ENOMEM;
3630 
3631 	oparams = memdup_user(_oparams, sizeof(*oparams));
3632 	if (IS_ERR(oparams)) {
3633 		err = PTR_ERR(oparams);
3634 		goto out;
3635 	}
3636 
3637 	snd_pcm_hw_convert_from_old_params(params, oparams);
3638 	err = snd_pcm_hw_params(substream, params);
3639 	if (err < 0)
3640 		goto out_old;
3641 
3642 	snd_pcm_hw_convert_to_old_params(oparams, params);
3643 	if (copy_to_user(_oparams, oparams, sizeof(*oparams)))
3644 		err = -EFAULT;
3645 out_old:
3646 	kfree(oparams);
3647 out:
3648 	kfree(params);
3649 	return err;
3650 }
3651 #endif /* CONFIG_SND_SUPPORT_OLD_API */
3652 
3653 #ifndef CONFIG_MMU
3654 static unsigned long snd_pcm_get_unmapped_area(struct file *file,
3655 					       unsigned long addr,
3656 					       unsigned long len,
3657 					       unsigned long pgoff,
3658 					       unsigned long flags)
3659 {
3660 	struct snd_pcm_file *pcm_file = file->private_data;
3661 	struct snd_pcm_substream *substream = pcm_file->substream;
3662 	struct snd_pcm_runtime *runtime = substream->runtime;
3663 	unsigned long offset = pgoff << PAGE_SHIFT;
3664 
3665 	switch (offset) {
3666 	case SNDRV_PCM_MMAP_OFFSET_STATUS:
3667 		return (unsigned long)runtime->status;
3668 	case SNDRV_PCM_MMAP_OFFSET_CONTROL:
3669 		return (unsigned long)runtime->control;
3670 	default:
3671 		return (unsigned long)runtime->dma_area + offset;
3672 	}
3673 }
3674 #else
3675 # define snd_pcm_get_unmapped_area NULL
3676 #endif
3677 
3678 /*
3679  *  Register section
3680  */
3681 
3682 const struct file_operations snd_pcm_f_ops[2] = {
3683 	{
3684 		.owner =		THIS_MODULE,
3685 		.write =		snd_pcm_write,
3686 		.write_iter =		snd_pcm_writev,
3687 		.open =			snd_pcm_playback_open,
3688 		.release =		snd_pcm_release,
3689 		.llseek =		no_llseek,
3690 		.poll =			snd_pcm_poll,
3691 		.unlocked_ioctl =	snd_pcm_ioctl,
3692 		.compat_ioctl = 	snd_pcm_ioctl_compat,
3693 		.mmap =			snd_pcm_mmap,
3694 		.fasync =		snd_pcm_fasync,
3695 		.get_unmapped_area =	snd_pcm_get_unmapped_area,
3696 	},
3697 	{
3698 		.owner =		THIS_MODULE,
3699 		.read =			snd_pcm_read,
3700 		.read_iter =		snd_pcm_readv,
3701 		.open =			snd_pcm_capture_open,
3702 		.release =		snd_pcm_release,
3703 		.llseek =		no_llseek,
3704 		.poll =			snd_pcm_poll,
3705 		.unlocked_ioctl =	snd_pcm_ioctl,
3706 		.compat_ioctl = 	snd_pcm_ioctl_compat,
3707 		.mmap =			snd_pcm_mmap,
3708 		.fasync =		snd_pcm_fasync,
3709 		.get_unmapped_area =	snd_pcm_get_unmapped_area,
3710 	}
3711 };
3712