xref: /openbmc/linux/sound/core/pcm_lib.c (revision 15d90a6a)
1 /*
2  *  Digital Audio (PCM) abstract layer
3  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4  *                   Abramo Bagnara <abramo@alsa-project.org>
5  *
6  *
7  *   This program is free software; you can redistribute it and/or modify
8  *   it under the terms of the GNU General Public License as published by
9  *   the Free Software Foundation; either version 2 of the License, or
10  *   (at your option) any later version.
11  *
12  *   This program is distributed in the hope that it will be useful,
13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *   GNU General Public License for more details.
16  *
17  *   You should have received a copy of the GNU General Public License
18  *   along with this program; if not, write to the Free Software
19  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
20  *
21  */
22 
23 #include <linux/slab.h>
24 #include <linux/sched/signal.h>
25 #include <linux/time.h>
26 #include <linux/math64.h>
27 #include <linux/export.h>
28 #include <sound/core.h>
29 #include <sound/control.h>
30 #include <sound/tlv.h>
31 #include <sound/info.h>
32 #include <sound/pcm.h>
33 #include <sound/pcm_params.h>
34 #include <sound/timer.h>
35 
36 #include "pcm_local.h"
37 
38 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
39 #define CREATE_TRACE_POINTS
40 #include "pcm_trace.h"
41 #else
42 #define trace_hwptr(substream, pos, in_interrupt)
43 #define trace_xrun(substream)
44 #define trace_hw_ptr_error(substream, reason)
45 #define trace_applptr(substream, prev, curr)
46 #endif
47 
48 static int fill_silence_frames(struct snd_pcm_substream *substream,
49 			       snd_pcm_uframes_t off, snd_pcm_uframes_t frames);
50 
51 /*
52  * fill ring buffer with silence
53  * runtime->silence_start: starting pointer to silence area
54  * runtime->silence_filled: size filled with silence
55  * runtime->silence_threshold: threshold from application
56  * runtime->silence_size: maximal size from application
57  *
58  * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
59  */
60 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
61 {
62 	struct snd_pcm_runtime *runtime = substream->runtime;
63 	snd_pcm_uframes_t frames, ofs, transfer;
64 	int err;
65 
66 	if (runtime->silence_size < runtime->boundary) {
67 		snd_pcm_sframes_t noise_dist, n;
68 		snd_pcm_uframes_t appl_ptr = READ_ONCE(runtime->control->appl_ptr);
69 		if (runtime->silence_start != appl_ptr) {
70 			n = appl_ptr - runtime->silence_start;
71 			if (n < 0)
72 				n += runtime->boundary;
73 			if ((snd_pcm_uframes_t)n < runtime->silence_filled)
74 				runtime->silence_filled -= n;
75 			else
76 				runtime->silence_filled = 0;
77 			runtime->silence_start = appl_ptr;
78 		}
79 		if (runtime->silence_filled >= runtime->buffer_size)
80 			return;
81 		noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
82 		if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
83 			return;
84 		frames = runtime->silence_threshold - noise_dist;
85 		if (frames > runtime->silence_size)
86 			frames = runtime->silence_size;
87 	} else {
88 		if (new_hw_ptr == ULONG_MAX) {	/* initialization */
89 			snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
90 			if (avail > runtime->buffer_size)
91 				avail = runtime->buffer_size;
92 			runtime->silence_filled = avail > 0 ? avail : 0;
93 			runtime->silence_start = (runtime->status->hw_ptr +
94 						  runtime->silence_filled) %
95 						 runtime->boundary;
96 		} else {
97 			ofs = runtime->status->hw_ptr;
98 			frames = new_hw_ptr - ofs;
99 			if ((snd_pcm_sframes_t)frames < 0)
100 				frames += runtime->boundary;
101 			runtime->silence_filled -= frames;
102 			if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
103 				runtime->silence_filled = 0;
104 				runtime->silence_start = new_hw_ptr;
105 			} else {
106 				runtime->silence_start = ofs;
107 			}
108 		}
109 		frames = runtime->buffer_size - runtime->silence_filled;
110 	}
111 	if (snd_BUG_ON(frames > runtime->buffer_size))
112 		return;
113 	if (frames == 0)
114 		return;
115 	ofs = runtime->silence_start % runtime->buffer_size;
116 	while (frames > 0) {
117 		transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
118 		err = fill_silence_frames(substream, ofs, transfer);
119 		snd_BUG_ON(err < 0);
120 		runtime->silence_filled += transfer;
121 		frames -= transfer;
122 		ofs = 0;
123 	}
124 }
125 
126 #ifdef CONFIG_SND_DEBUG
127 void snd_pcm_debug_name(struct snd_pcm_substream *substream,
128 			   char *name, size_t len)
129 {
130 	snprintf(name, len, "pcmC%dD%d%c:%d",
131 		 substream->pcm->card->number,
132 		 substream->pcm->device,
133 		 substream->stream ? 'c' : 'p',
134 		 substream->number);
135 }
136 EXPORT_SYMBOL(snd_pcm_debug_name);
137 #endif
138 
139 #define XRUN_DEBUG_BASIC	(1<<0)
140 #define XRUN_DEBUG_STACK	(1<<1)	/* dump also stack */
141 #define XRUN_DEBUG_JIFFIESCHECK	(1<<2)	/* do jiffies check */
142 
143 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
144 
145 #define xrun_debug(substream, mask) \
146 			((substream)->pstr->xrun_debug & (mask))
147 #else
148 #define xrun_debug(substream, mask)	0
149 #endif
150 
151 #define dump_stack_on_xrun(substream) do {			\
152 		if (xrun_debug(substream, XRUN_DEBUG_STACK))	\
153 			dump_stack();				\
154 	} while (0)
155 
156 /* call with stream lock held */
157 void __snd_pcm_xrun(struct snd_pcm_substream *substream)
158 {
159 	struct snd_pcm_runtime *runtime = substream->runtime;
160 
161 	trace_xrun(substream);
162 	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
163 		snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
164 	snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
165 	if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
166 		char name[16];
167 		snd_pcm_debug_name(substream, name, sizeof(name));
168 		pcm_warn(substream->pcm, "XRUN: %s\n", name);
169 		dump_stack_on_xrun(substream);
170 	}
171 }
172 
173 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
174 #define hw_ptr_error(substream, in_interrupt, reason, fmt, args...)	\
175 	do {								\
176 		trace_hw_ptr_error(substream, reason);	\
177 		if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {		\
178 			pr_err_ratelimited("ALSA: PCM: [%c] " reason ": " fmt, \
179 					   (in_interrupt) ? 'Q' : 'P', ##args);	\
180 			dump_stack_on_xrun(substream);			\
181 		}							\
182 	} while (0)
183 
184 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
185 
186 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
187 
188 #endif
189 
190 int snd_pcm_update_state(struct snd_pcm_substream *substream,
191 			 struct snd_pcm_runtime *runtime)
192 {
193 	snd_pcm_uframes_t avail;
194 
195 	avail = snd_pcm_avail(substream);
196 	if (avail > runtime->avail_max)
197 		runtime->avail_max = avail;
198 	if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
199 		if (avail >= runtime->buffer_size) {
200 			snd_pcm_drain_done(substream);
201 			return -EPIPE;
202 		}
203 	} else {
204 		if (avail >= runtime->stop_threshold) {
205 			__snd_pcm_xrun(substream);
206 			return -EPIPE;
207 		}
208 	}
209 	if (runtime->twake) {
210 		if (avail >= runtime->twake)
211 			wake_up(&runtime->tsleep);
212 	} else if (avail >= runtime->control->avail_min)
213 		wake_up(&runtime->sleep);
214 	return 0;
215 }
216 
217 static void update_audio_tstamp(struct snd_pcm_substream *substream,
218 				struct timespec *curr_tstamp,
219 				struct timespec *audio_tstamp)
220 {
221 	struct snd_pcm_runtime *runtime = substream->runtime;
222 	u64 audio_frames, audio_nsecs;
223 	struct timespec driver_tstamp;
224 
225 	if (runtime->tstamp_mode != SNDRV_PCM_TSTAMP_ENABLE)
226 		return;
227 
228 	if (!(substream->ops->get_time_info) ||
229 		(runtime->audio_tstamp_report.actual_type ==
230 			SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
231 
232 		/*
233 		 * provide audio timestamp derived from pointer position
234 		 * add delay only if requested
235 		 */
236 
237 		audio_frames = runtime->hw_ptr_wrap + runtime->status->hw_ptr;
238 
239 		if (runtime->audio_tstamp_config.report_delay) {
240 			if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
241 				audio_frames -=  runtime->delay;
242 			else
243 				audio_frames +=  runtime->delay;
244 		}
245 		audio_nsecs = div_u64(audio_frames * 1000000000LL,
246 				runtime->rate);
247 		*audio_tstamp = ns_to_timespec(audio_nsecs);
248 	}
249 	if (!timespec_equal(&runtime->status->audio_tstamp, audio_tstamp)) {
250 		runtime->status->audio_tstamp = *audio_tstamp;
251 		runtime->status->tstamp = *curr_tstamp;
252 	}
253 
254 	/*
255 	 * re-take a driver timestamp to let apps detect if the reference tstamp
256 	 * read by low-level hardware was provided with a delay
257 	 */
258 	snd_pcm_gettime(substream->runtime, (struct timespec *)&driver_tstamp);
259 	runtime->driver_tstamp = driver_tstamp;
260 }
261 
262 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
263 				  unsigned int in_interrupt)
264 {
265 	struct snd_pcm_runtime *runtime = substream->runtime;
266 	snd_pcm_uframes_t pos;
267 	snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
268 	snd_pcm_sframes_t hdelta, delta;
269 	unsigned long jdelta;
270 	unsigned long curr_jiffies;
271 	struct timespec curr_tstamp;
272 	struct timespec audio_tstamp;
273 	int crossed_boundary = 0;
274 
275 	old_hw_ptr = runtime->status->hw_ptr;
276 
277 	/*
278 	 * group pointer, time and jiffies reads to allow for more
279 	 * accurate correlations/corrections.
280 	 * The values are stored at the end of this routine after
281 	 * corrections for hw_ptr position
282 	 */
283 	pos = substream->ops->pointer(substream);
284 	curr_jiffies = jiffies;
285 	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
286 		if ((substream->ops->get_time_info) &&
287 			(runtime->audio_tstamp_config.type_requested != SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
288 			substream->ops->get_time_info(substream, &curr_tstamp,
289 						&audio_tstamp,
290 						&runtime->audio_tstamp_config,
291 						&runtime->audio_tstamp_report);
292 
293 			/* re-test in case tstamp type is not supported in hardware and was demoted to DEFAULT */
294 			if (runtime->audio_tstamp_report.actual_type == SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)
295 				snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
296 		} else
297 			snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
298 	}
299 
300 	if (pos == SNDRV_PCM_POS_XRUN) {
301 		__snd_pcm_xrun(substream);
302 		return -EPIPE;
303 	}
304 	if (pos >= runtime->buffer_size) {
305 		if (printk_ratelimit()) {
306 			char name[16];
307 			snd_pcm_debug_name(substream, name, sizeof(name));
308 			pcm_err(substream->pcm,
309 				"invalid position: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
310 				name, pos, runtime->buffer_size,
311 				runtime->period_size);
312 		}
313 		pos = 0;
314 	}
315 	pos -= pos % runtime->min_align;
316 	trace_hwptr(substream, pos, in_interrupt);
317 	hw_base = runtime->hw_ptr_base;
318 	new_hw_ptr = hw_base + pos;
319 	if (in_interrupt) {
320 		/* we know that one period was processed */
321 		/* delta = "expected next hw_ptr" for in_interrupt != 0 */
322 		delta = runtime->hw_ptr_interrupt + runtime->period_size;
323 		if (delta > new_hw_ptr) {
324 			/* check for double acknowledged interrupts */
325 			hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
326 			if (hdelta > runtime->hw_ptr_buffer_jiffies/2 + 1) {
327 				hw_base += runtime->buffer_size;
328 				if (hw_base >= runtime->boundary) {
329 					hw_base = 0;
330 					crossed_boundary++;
331 				}
332 				new_hw_ptr = hw_base + pos;
333 				goto __delta;
334 			}
335 		}
336 	}
337 	/* new_hw_ptr might be lower than old_hw_ptr in case when */
338 	/* pointer crosses the end of the ring buffer */
339 	if (new_hw_ptr < old_hw_ptr) {
340 		hw_base += runtime->buffer_size;
341 		if (hw_base >= runtime->boundary) {
342 			hw_base = 0;
343 			crossed_boundary++;
344 		}
345 		new_hw_ptr = hw_base + pos;
346 	}
347       __delta:
348 	delta = new_hw_ptr - old_hw_ptr;
349 	if (delta < 0)
350 		delta += runtime->boundary;
351 
352 	if (runtime->no_period_wakeup) {
353 		snd_pcm_sframes_t xrun_threshold;
354 		/*
355 		 * Without regular period interrupts, we have to check
356 		 * the elapsed time to detect xruns.
357 		 */
358 		jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
359 		if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
360 			goto no_delta_check;
361 		hdelta = jdelta - delta * HZ / runtime->rate;
362 		xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
363 		while (hdelta > xrun_threshold) {
364 			delta += runtime->buffer_size;
365 			hw_base += runtime->buffer_size;
366 			if (hw_base >= runtime->boundary) {
367 				hw_base = 0;
368 				crossed_boundary++;
369 			}
370 			new_hw_ptr = hw_base + pos;
371 			hdelta -= runtime->hw_ptr_buffer_jiffies;
372 		}
373 		goto no_delta_check;
374 	}
375 
376 	/* something must be really wrong */
377 	if (delta >= runtime->buffer_size + runtime->period_size) {
378 		hw_ptr_error(substream, in_interrupt, "Unexpected hw_ptr",
379 			     "(stream=%i, pos=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
380 			     substream->stream, (long)pos,
381 			     (long)new_hw_ptr, (long)old_hw_ptr);
382 		return 0;
383 	}
384 
385 	/* Do jiffies check only in xrun_debug mode */
386 	if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
387 		goto no_jiffies_check;
388 
389 	/* Skip the jiffies check for hardwares with BATCH flag.
390 	 * Such hardware usually just increases the position at each IRQ,
391 	 * thus it can't give any strange position.
392 	 */
393 	if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
394 		goto no_jiffies_check;
395 	hdelta = delta;
396 	if (hdelta < runtime->delay)
397 		goto no_jiffies_check;
398 	hdelta -= runtime->delay;
399 	jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
400 	if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
401 		delta = jdelta /
402 			(((runtime->period_size * HZ) / runtime->rate)
403 								+ HZ/100);
404 		/* move new_hw_ptr according jiffies not pos variable */
405 		new_hw_ptr = old_hw_ptr;
406 		hw_base = delta;
407 		/* use loop to avoid checks for delta overflows */
408 		/* the delta value is small or zero in most cases */
409 		while (delta > 0) {
410 			new_hw_ptr += runtime->period_size;
411 			if (new_hw_ptr >= runtime->boundary) {
412 				new_hw_ptr -= runtime->boundary;
413 				crossed_boundary--;
414 			}
415 			delta--;
416 		}
417 		/* align hw_base to buffer_size */
418 		hw_ptr_error(substream, in_interrupt, "hw_ptr skipping",
419 			     "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
420 			     (long)pos, (long)hdelta,
421 			     (long)runtime->period_size, jdelta,
422 			     ((hdelta * HZ) / runtime->rate), hw_base,
423 			     (unsigned long)old_hw_ptr,
424 			     (unsigned long)new_hw_ptr);
425 		/* reset values to proper state */
426 		delta = 0;
427 		hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
428 	}
429  no_jiffies_check:
430 	if (delta > runtime->period_size + runtime->period_size / 2) {
431 		hw_ptr_error(substream, in_interrupt,
432 			     "Lost interrupts?",
433 			     "(stream=%i, delta=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
434 			     substream->stream, (long)delta,
435 			     (long)new_hw_ptr,
436 			     (long)old_hw_ptr);
437 	}
438 
439  no_delta_check:
440 	if (runtime->status->hw_ptr == new_hw_ptr) {
441 		update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
442 		return 0;
443 	}
444 
445 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
446 	    runtime->silence_size > 0)
447 		snd_pcm_playback_silence(substream, new_hw_ptr);
448 
449 	if (in_interrupt) {
450 		delta = new_hw_ptr - runtime->hw_ptr_interrupt;
451 		if (delta < 0)
452 			delta += runtime->boundary;
453 		delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
454 		runtime->hw_ptr_interrupt += delta;
455 		if (runtime->hw_ptr_interrupt >= runtime->boundary)
456 			runtime->hw_ptr_interrupt -= runtime->boundary;
457 	}
458 	runtime->hw_ptr_base = hw_base;
459 	runtime->status->hw_ptr = new_hw_ptr;
460 	runtime->hw_ptr_jiffies = curr_jiffies;
461 	if (crossed_boundary) {
462 		snd_BUG_ON(crossed_boundary != 1);
463 		runtime->hw_ptr_wrap += runtime->boundary;
464 	}
465 
466 	update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
467 
468 	return snd_pcm_update_state(substream, runtime);
469 }
470 
471 /* CAUTION: call it with irq disabled */
472 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
473 {
474 	return snd_pcm_update_hw_ptr0(substream, 0);
475 }
476 
477 /**
478  * snd_pcm_set_ops - set the PCM operators
479  * @pcm: the pcm instance
480  * @direction: stream direction, SNDRV_PCM_STREAM_XXX
481  * @ops: the operator table
482  *
483  * Sets the given PCM operators to the pcm instance.
484  */
485 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
486 		     const struct snd_pcm_ops *ops)
487 {
488 	struct snd_pcm_str *stream = &pcm->streams[direction];
489 	struct snd_pcm_substream *substream;
490 
491 	for (substream = stream->substream; substream != NULL; substream = substream->next)
492 		substream->ops = ops;
493 }
494 EXPORT_SYMBOL(snd_pcm_set_ops);
495 
496 /**
497  * snd_pcm_sync - set the PCM sync id
498  * @substream: the pcm substream
499  *
500  * Sets the PCM sync identifier for the card.
501  */
502 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
503 {
504 	struct snd_pcm_runtime *runtime = substream->runtime;
505 
506 	runtime->sync.id32[0] = substream->pcm->card->number;
507 	runtime->sync.id32[1] = -1;
508 	runtime->sync.id32[2] = -1;
509 	runtime->sync.id32[3] = -1;
510 }
511 EXPORT_SYMBOL(snd_pcm_set_sync);
512 
513 /*
514  *  Standard ioctl routine
515  */
516 
517 static inline unsigned int div32(unsigned int a, unsigned int b,
518 				 unsigned int *r)
519 {
520 	if (b == 0) {
521 		*r = 0;
522 		return UINT_MAX;
523 	}
524 	*r = a % b;
525 	return a / b;
526 }
527 
528 static inline unsigned int div_down(unsigned int a, unsigned int b)
529 {
530 	if (b == 0)
531 		return UINT_MAX;
532 	return a / b;
533 }
534 
535 static inline unsigned int div_up(unsigned int a, unsigned int b)
536 {
537 	unsigned int r;
538 	unsigned int q;
539 	if (b == 0)
540 		return UINT_MAX;
541 	q = div32(a, b, &r);
542 	if (r)
543 		++q;
544 	return q;
545 }
546 
547 static inline unsigned int mul(unsigned int a, unsigned int b)
548 {
549 	if (a == 0)
550 		return 0;
551 	if (div_down(UINT_MAX, a) < b)
552 		return UINT_MAX;
553 	return a * b;
554 }
555 
556 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
557 				    unsigned int c, unsigned int *r)
558 {
559 	u_int64_t n = (u_int64_t) a * b;
560 	if (c == 0) {
561 		*r = 0;
562 		return UINT_MAX;
563 	}
564 	n = div_u64_rem(n, c, r);
565 	if (n >= UINT_MAX) {
566 		*r = 0;
567 		return UINT_MAX;
568 	}
569 	return n;
570 }
571 
572 /**
573  * snd_interval_refine - refine the interval value of configurator
574  * @i: the interval value to refine
575  * @v: the interval value to refer to
576  *
577  * Refines the interval value with the reference value.
578  * The interval is changed to the range satisfying both intervals.
579  * The interval status (min, max, integer, etc.) are evaluated.
580  *
581  * Return: Positive if the value is changed, zero if it's not changed, or a
582  * negative error code.
583  */
584 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
585 {
586 	int changed = 0;
587 	if (snd_BUG_ON(snd_interval_empty(i)))
588 		return -EINVAL;
589 	if (i->min < v->min) {
590 		i->min = v->min;
591 		i->openmin = v->openmin;
592 		changed = 1;
593 	} else if (i->min == v->min && !i->openmin && v->openmin) {
594 		i->openmin = 1;
595 		changed = 1;
596 	}
597 	if (i->max > v->max) {
598 		i->max = v->max;
599 		i->openmax = v->openmax;
600 		changed = 1;
601 	} else if (i->max == v->max && !i->openmax && v->openmax) {
602 		i->openmax = 1;
603 		changed = 1;
604 	}
605 	if (!i->integer && v->integer) {
606 		i->integer = 1;
607 		changed = 1;
608 	}
609 	if (i->integer) {
610 		if (i->openmin) {
611 			i->min++;
612 			i->openmin = 0;
613 		}
614 		if (i->openmax) {
615 			i->max--;
616 			i->openmax = 0;
617 		}
618 	} else if (!i->openmin && !i->openmax && i->min == i->max)
619 		i->integer = 1;
620 	if (snd_interval_checkempty(i)) {
621 		snd_interval_none(i);
622 		return -EINVAL;
623 	}
624 	return changed;
625 }
626 EXPORT_SYMBOL(snd_interval_refine);
627 
628 static int snd_interval_refine_first(struct snd_interval *i)
629 {
630 	const unsigned int last_max = i->max;
631 
632 	if (snd_BUG_ON(snd_interval_empty(i)))
633 		return -EINVAL;
634 	if (snd_interval_single(i))
635 		return 0;
636 	i->max = i->min;
637 	if (i->openmin)
638 		i->max++;
639 	/* only exclude max value if also excluded before refine */
640 	i->openmax = (i->openmax && i->max >= last_max);
641 	return 1;
642 }
643 
644 static int snd_interval_refine_last(struct snd_interval *i)
645 {
646 	const unsigned int last_min = i->min;
647 
648 	if (snd_BUG_ON(snd_interval_empty(i)))
649 		return -EINVAL;
650 	if (snd_interval_single(i))
651 		return 0;
652 	i->min = i->max;
653 	if (i->openmax)
654 		i->min--;
655 	/* only exclude min value if also excluded before refine */
656 	i->openmin = (i->openmin && i->min <= last_min);
657 	return 1;
658 }
659 
660 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
661 {
662 	if (a->empty || b->empty) {
663 		snd_interval_none(c);
664 		return;
665 	}
666 	c->empty = 0;
667 	c->min = mul(a->min, b->min);
668 	c->openmin = (a->openmin || b->openmin);
669 	c->max = mul(a->max,  b->max);
670 	c->openmax = (a->openmax || b->openmax);
671 	c->integer = (a->integer && b->integer);
672 }
673 
674 /**
675  * snd_interval_div - refine the interval value with division
676  * @a: dividend
677  * @b: divisor
678  * @c: quotient
679  *
680  * c = a / b
681  *
682  * Returns non-zero if the value is changed, zero if not changed.
683  */
684 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
685 {
686 	unsigned int r;
687 	if (a->empty || b->empty) {
688 		snd_interval_none(c);
689 		return;
690 	}
691 	c->empty = 0;
692 	c->min = div32(a->min, b->max, &r);
693 	c->openmin = (r || a->openmin || b->openmax);
694 	if (b->min > 0) {
695 		c->max = div32(a->max, b->min, &r);
696 		if (r) {
697 			c->max++;
698 			c->openmax = 1;
699 		} else
700 			c->openmax = (a->openmax || b->openmin);
701 	} else {
702 		c->max = UINT_MAX;
703 		c->openmax = 0;
704 	}
705 	c->integer = 0;
706 }
707 
708 /**
709  * snd_interval_muldivk - refine the interval value
710  * @a: dividend 1
711  * @b: dividend 2
712  * @k: divisor (as integer)
713  * @c: result
714   *
715  * c = a * b / k
716  *
717  * Returns non-zero if the value is changed, zero if not changed.
718  */
719 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
720 		      unsigned int k, struct snd_interval *c)
721 {
722 	unsigned int r;
723 	if (a->empty || b->empty) {
724 		snd_interval_none(c);
725 		return;
726 	}
727 	c->empty = 0;
728 	c->min = muldiv32(a->min, b->min, k, &r);
729 	c->openmin = (r || a->openmin || b->openmin);
730 	c->max = muldiv32(a->max, b->max, k, &r);
731 	if (r) {
732 		c->max++;
733 		c->openmax = 1;
734 	} else
735 		c->openmax = (a->openmax || b->openmax);
736 	c->integer = 0;
737 }
738 
739 /**
740  * snd_interval_mulkdiv - refine the interval value
741  * @a: dividend 1
742  * @k: dividend 2 (as integer)
743  * @b: divisor
744  * @c: result
745  *
746  * c = a * k / b
747  *
748  * Returns non-zero if the value is changed, zero if not changed.
749  */
750 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
751 		      const struct snd_interval *b, struct snd_interval *c)
752 {
753 	unsigned int r;
754 	if (a->empty || b->empty) {
755 		snd_interval_none(c);
756 		return;
757 	}
758 	c->empty = 0;
759 	c->min = muldiv32(a->min, k, b->max, &r);
760 	c->openmin = (r || a->openmin || b->openmax);
761 	if (b->min > 0) {
762 		c->max = muldiv32(a->max, k, b->min, &r);
763 		if (r) {
764 			c->max++;
765 			c->openmax = 1;
766 		} else
767 			c->openmax = (a->openmax || b->openmin);
768 	} else {
769 		c->max = UINT_MAX;
770 		c->openmax = 0;
771 	}
772 	c->integer = 0;
773 }
774 
775 /* ---- */
776 
777 
778 /**
779  * snd_interval_ratnum - refine the interval value
780  * @i: interval to refine
781  * @rats_count: number of ratnum_t
782  * @rats: ratnum_t array
783  * @nump: pointer to store the resultant numerator
784  * @denp: pointer to store the resultant denominator
785  *
786  * Return: Positive if the value is changed, zero if it's not changed, or a
787  * negative error code.
788  */
789 int snd_interval_ratnum(struct snd_interval *i,
790 			unsigned int rats_count, const struct snd_ratnum *rats,
791 			unsigned int *nump, unsigned int *denp)
792 {
793 	unsigned int best_num, best_den;
794 	int best_diff;
795 	unsigned int k;
796 	struct snd_interval t;
797 	int err;
798 	unsigned int result_num, result_den;
799 	int result_diff;
800 
801 	best_num = best_den = best_diff = 0;
802 	for (k = 0; k < rats_count; ++k) {
803 		unsigned int num = rats[k].num;
804 		unsigned int den;
805 		unsigned int q = i->min;
806 		int diff;
807 		if (q == 0)
808 			q = 1;
809 		den = div_up(num, q);
810 		if (den < rats[k].den_min)
811 			continue;
812 		if (den > rats[k].den_max)
813 			den = rats[k].den_max;
814 		else {
815 			unsigned int r;
816 			r = (den - rats[k].den_min) % rats[k].den_step;
817 			if (r != 0)
818 				den -= r;
819 		}
820 		diff = num - q * den;
821 		if (diff < 0)
822 			diff = -diff;
823 		if (best_num == 0 ||
824 		    diff * best_den < best_diff * den) {
825 			best_diff = diff;
826 			best_den = den;
827 			best_num = num;
828 		}
829 	}
830 	if (best_den == 0) {
831 		i->empty = 1;
832 		return -EINVAL;
833 	}
834 	t.min = div_down(best_num, best_den);
835 	t.openmin = !!(best_num % best_den);
836 
837 	result_num = best_num;
838 	result_diff = best_diff;
839 	result_den = best_den;
840 	best_num = best_den = best_diff = 0;
841 	for (k = 0; k < rats_count; ++k) {
842 		unsigned int num = rats[k].num;
843 		unsigned int den;
844 		unsigned int q = i->max;
845 		int diff;
846 		if (q == 0) {
847 			i->empty = 1;
848 			return -EINVAL;
849 		}
850 		den = div_down(num, q);
851 		if (den > rats[k].den_max)
852 			continue;
853 		if (den < rats[k].den_min)
854 			den = rats[k].den_min;
855 		else {
856 			unsigned int r;
857 			r = (den - rats[k].den_min) % rats[k].den_step;
858 			if (r != 0)
859 				den += rats[k].den_step - r;
860 		}
861 		diff = q * den - num;
862 		if (diff < 0)
863 			diff = -diff;
864 		if (best_num == 0 ||
865 		    diff * best_den < best_diff * den) {
866 			best_diff = diff;
867 			best_den = den;
868 			best_num = num;
869 		}
870 	}
871 	if (best_den == 0) {
872 		i->empty = 1;
873 		return -EINVAL;
874 	}
875 	t.max = div_up(best_num, best_den);
876 	t.openmax = !!(best_num % best_den);
877 	t.integer = 0;
878 	err = snd_interval_refine(i, &t);
879 	if (err < 0)
880 		return err;
881 
882 	if (snd_interval_single(i)) {
883 		if (best_diff * result_den < result_diff * best_den) {
884 			result_num = best_num;
885 			result_den = best_den;
886 		}
887 		if (nump)
888 			*nump = result_num;
889 		if (denp)
890 			*denp = result_den;
891 	}
892 	return err;
893 }
894 EXPORT_SYMBOL(snd_interval_ratnum);
895 
896 /**
897  * snd_interval_ratden - refine the interval value
898  * @i: interval to refine
899  * @rats_count: number of struct ratden
900  * @rats: struct ratden array
901  * @nump: pointer to store the resultant numerator
902  * @denp: pointer to store the resultant denominator
903  *
904  * Return: Positive if the value is changed, zero if it's not changed, or a
905  * negative error code.
906  */
907 static int snd_interval_ratden(struct snd_interval *i,
908 			       unsigned int rats_count,
909 			       const struct snd_ratden *rats,
910 			       unsigned int *nump, unsigned int *denp)
911 {
912 	unsigned int best_num, best_diff, best_den;
913 	unsigned int k;
914 	struct snd_interval t;
915 	int err;
916 
917 	best_num = best_den = best_diff = 0;
918 	for (k = 0; k < rats_count; ++k) {
919 		unsigned int num;
920 		unsigned int den = rats[k].den;
921 		unsigned int q = i->min;
922 		int diff;
923 		num = mul(q, den);
924 		if (num > rats[k].num_max)
925 			continue;
926 		if (num < rats[k].num_min)
927 			num = rats[k].num_max;
928 		else {
929 			unsigned int r;
930 			r = (num - rats[k].num_min) % rats[k].num_step;
931 			if (r != 0)
932 				num += rats[k].num_step - r;
933 		}
934 		diff = num - q * den;
935 		if (best_num == 0 ||
936 		    diff * best_den < best_diff * den) {
937 			best_diff = diff;
938 			best_den = den;
939 			best_num = num;
940 		}
941 	}
942 	if (best_den == 0) {
943 		i->empty = 1;
944 		return -EINVAL;
945 	}
946 	t.min = div_down(best_num, best_den);
947 	t.openmin = !!(best_num % best_den);
948 
949 	best_num = best_den = best_diff = 0;
950 	for (k = 0; k < rats_count; ++k) {
951 		unsigned int num;
952 		unsigned int den = rats[k].den;
953 		unsigned int q = i->max;
954 		int diff;
955 		num = mul(q, den);
956 		if (num < rats[k].num_min)
957 			continue;
958 		if (num > rats[k].num_max)
959 			num = rats[k].num_max;
960 		else {
961 			unsigned int r;
962 			r = (num - rats[k].num_min) % rats[k].num_step;
963 			if (r != 0)
964 				num -= r;
965 		}
966 		diff = q * den - num;
967 		if (best_num == 0 ||
968 		    diff * best_den < best_diff * den) {
969 			best_diff = diff;
970 			best_den = den;
971 			best_num = num;
972 		}
973 	}
974 	if (best_den == 0) {
975 		i->empty = 1;
976 		return -EINVAL;
977 	}
978 	t.max = div_up(best_num, best_den);
979 	t.openmax = !!(best_num % best_den);
980 	t.integer = 0;
981 	err = snd_interval_refine(i, &t);
982 	if (err < 0)
983 		return err;
984 
985 	if (snd_interval_single(i)) {
986 		if (nump)
987 			*nump = best_num;
988 		if (denp)
989 			*denp = best_den;
990 	}
991 	return err;
992 }
993 
994 /**
995  * snd_interval_list - refine the interval value from the list
996  * @i: the interval value to refine
997  * @count: the number of elements in the list
998  * @list: the value list
999  * @mask: the bit-mask to evaluate
1000  *
1001  * Refines the interval value from the list.
1002  * When mask is non-zero, only the elements corresponding to bit 1 are
1003  * evaluated.
1004  *
1005  * Return: Positive if the value is changed, zero if it's not changed, or a
1006  * negative error code.
1007  */
1008 int snd_interval_list(struct snd_interval *i, unsigned int count,
1009 		      const unsigned int *list, unsigned int mask)
1010 {
1011         unsigned int k;
1012 	struct snd_interval list_range;
1013 
1014 	if (!count) {
1015 		i->empty = 1;
1016 		return -EINVAL;
1017 	}
1018 	snd_interval_any(&list_range);
1019 	list_range.min = UINT_MAX;
1020 	list_range.max = 0;
1021         for (k = 0; k < count; k++) {
1022 		if (mask && !(mask & (1 << k)))
1023 			continue;
1024 		if (!snd_interval_test(i, list[k]))
1025 			continue;
1026 		list_range.min = min(list_range.min, list[k]);
1027 		list_range.max = max(list_range.max, list[k]);
1028         }
1029 	return snd_interval_refine(i, &list_range);
1030 }
1031 EXPORT_SYMBOL(snd_interval_list);
1032 
1033 /**
1034  * snd_interval_ranges - refine the interval value from the list of ranges
1035  * @i: the interval value to refine
1036  * @count: the number of elements in the list of ranges
1037  * @ranges: the ranges list
1038  * @mask: the bit-mask to evaluate
1039  *
1040  * Refines the interval value from the list of ranges.
1041  * When mask is non-zero, only the elements corresponding to bit 1 are
1042  * evaluated.
1043  *
1044  * Return: Positive if the value is changed, zero if it's not changed, or a
1045  * negative error code.
1046  */
1047 int snd_interval_ranges(struct snd_interval *i, unsigned int count,
1048 			const struct snd_interval *ranges, unsigned int mask)
1049 {
1050 	unsigned int k;
1051 	struct snd_interval range_union;
1052 	struct snd_interval range;
1053 
1054 	if (!count) {
1055 		snd_interval_none(i);
1056 		return -EINVAL;
1057 	}
1058 	snd_interval_any(&range_union);
1059 	range_union.min = UINT_MAX;
1060 	range_union.max = 0;
1061 	for (k = 0; k < count; k++) {
1062 		if (mask && !(mask & (1 << k)))
1063 			continue;
1064 		snd_interval_copy(&range, &ranges[k]);
1065 		if (snd_interval_refine(&range, i) < 0)
1066 			continue;
1067 		if (snd_interval_empty(&range))
1068 			continue;
1069 
1070 		if (range.min < range_union.min) {
1071 			range_union.min = range.min;
1072 			range_union.openmin = 1;
1073 		}
1074 		if (range.min == range_union.min && !range.openmin)
1075 			range_union.openmin = 0;
1076 		if (range.max > range_union.max) {
1077 			range_union.max = range.max;
1078 			range_union.openmax = 1;
1079 		}
1080 		if (range.max == range_union.max && !range.openmax)
1081 			range_union.openmax = 0;
1082 	}
1083 	return snd_interval_refine(i, &range_union);
1084 }
1085 EXPORT_SYMBOL(snd_interval_ranges);
1086 
1087 static int snd_interval_step(struct snd_interval *i, unsigned int step)
1088 {
1089 	unsigned int n;
1090 	int changed = 0;
1091 	n = i->min % step;
1092 	if (n != 0 || i->openmin) {
1093 		i->min += step - n;
1094 		i->openmin = 0;
1095 		changed = 1;
1096 	}
1097 	n = i->max % step;
1098 	if (n != 0 || i->openmax) {
1099 		i->max -= n;
1100 		i->openmax = 0;
1101 		changed = 1;
1102 	}
1103 	if (snd_interval_checkempty(i)) {
1104 		i->empty = 1;
1105 		return -EINVAL;
1106 	}
1107 	return changed;
1108 }
1109 
1110 /* Info constraints helpers */
1111 
1112 /**
1113  * snd_pcm_hw_rule_add - add the hw-constraint rule
1114  * @runtime: the pcm runtime instance
1115  * @cond: condition bits
1116  * @var: the variable to evaluate
1117  * @func: the evaluation function
1118  * @private: the private data pointer passed to function
1119  * @dep: the dependent variables
1120  *
1121  * Return: Zero if successful, or a negative error code on failure.
1122  */
1123 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1124 			int var,
1125 			snd_pcm_hw_rule_func_t func, void *private,
1126 			int dep, ...)
1127 {
1128 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1129 	struct snd_pcm_hw_rule *c;
1130 	unsigned int k;
1131 	va_list args;
1132 	va_start(args, dep);
1133 	if (constrs->rules_num >= constrs->rules_all) {
1134 		struct snd_pcm_hw_rule *new;
1135 		unsigned int new_rules = constrs->rules_all + 16;
1136 		new = krealloc(constrs->rules, new_rules * sizeof(*c),
1137 			       GFP_KERNEL);
1138 		if (!new) {
1139 			va_end(args);
1140 			return -ENOMEM;
1141 		}
1142 		constrs->rules = new;
1143 		constrs->rules_all = new_rules;
1144 	}
1145 	c = &constrs->rules[constrs->rules_num];
1146 	c->cond = cond;
1147 	c->func = func;
1148 	c->var = var;
1149 	c->private = private;
1150 	k = 0;
1151 	while (1) {
1152 		if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1153 			va_end(args);
1154 			return -EINVAL;
1155 		}
1156 		c->deps[k++] = dep;
1157 		if (dep < 0)
1158 			break;
1159 		dep = va_arg(args, int);
1160 	}
1161 	constrs->rules_num++;
1162 	va_end(args);
1163 	return 0;
1164 }
1165 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1166 
1167 /**
1168  * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1169  * @runtime: PCM runtime instance
1170  * @var: hw_params variable to apply the mask
1171  * @mask: the bitmap mask
1172  *
1173  * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1174  *
1175  * Return: Zero if successful, or a negative error code on failure.
1176  */
1177 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1178 			       u_int32_t mask)
1179 {
1180 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1181 	struct snd_mask *maskp = constrs_mask(constrs, var);
1182 	*maskp->bits &= mask;
1183 	memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1184 	if (*maskp->bits == 0)
1185 		return -EINVAL;
1186 	return 0;
1187 }
1188 
1189 /**
1190  * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1191  * @runtime: PCM runtime instance
1192  * @var: hw_params variable to apply the mask
1193  * @mask: the 64bit bitmap mask
1194  *
1195  * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1196  *
1197  * Return: Zero if successful, or a negative error code on failure.
1198  */
1199 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1200 				 u_int64_t mask)
1201 {
1202 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1203 	struct snd_mask *maskp = constrs_mask(constrs, var);
1204 	maskp->bits[0] &= (u_int32_t)mask;
1205 	maskp->bits[1] &= (u_int32_t)(mask >> 32);
1206 	memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1207 	if (! maskp->bits[0] && ! maskp->bits[1])
1208 		return -EINVAL;
1209 	return 0;
1210 }
1211 EXPORT_SYMBOL(snd_pcm_hw_constraint_mask64);
1212 
1213 /**
1214  * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1215  * @runtime: PCM runtime instance
1216  * @var: hw_params variable to apply the integer constraint
1217  *
1218  * Apply the constraint of integer to an interval parameter.
1219  *
1220  * Return: Positive if the value is changed, zero if it's not changed, or a
1221  * negative error code.
1222  */
1223 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1224 {
1225 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1226 	return snd_interval_setinteger(constrs_interval(constrs, var));
1227 }
1228 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1229 
1230 /**
1231  * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1232  * @runtime: PCM runtime instance
1233  * @var: hw_params variable to apply the range
1234  * @min: the minimal value
1235  * @max: the maximal value
1236  *
1237  * Apply the min/max range constraint to an interval parameter.
1238  *
1239  * Return: Positive if the value is changed, zero if it's not changed, or a
1240  * negative error code.
1241  */
1242 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1243 				 unsigned int min, unsigned int max)
1244 {
1245 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1246 	struct snd_interval t;
1247 	t.min = min;
1248 	t.max = max;
1249 	t.openmin = t.openmax = 0;
1250 	t.integer = 0;
1251 	return snd_interval_refine(constrs_interval(constrs, var), &t);
1252 }
1253 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1254 
1255 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1256 				struct snd_pcm_hw_rule *rule)
1257 {
1258 	struct snd_pcm_hw_constraint_list *list = rule->private;
1259 	return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1260 }
1261 
1262 
1263 /**
1264  * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1265  * @runtime: PCM runtime instance
1266  * @cond: condition bits
1267  * @var: hw_params variable to apply the list constraint
1268  * @l: list
1269  *
1270  * Apply the list of constraints to an interval parameter.
1271  *
1272  * Return: Zero if successful, or a negative error code on failure.
1273  */
1274 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1275 			       unsigned int cond,
1276 			       snd_pcm_hw_param_t var,
1277 			       const struct snd_pcm_hw_constraint_list *l)
1278 {
1279 	return snd_pcm_hw_rule_add(runtime, cond, var,
1280 				   snd_pcm_hw_rule_list, (void *)l,
1281 				   var, -1);
1282 }
1283 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1284 
1285 static int snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params *params,
1286 				  struct snd_pcm_hw_rule *rule)
1287 {
1288 	struct snd_pcm_hw_constraint_ranges *r = rule->private;
1289 	return snd_interval_ranges(hw_param_interval(params, rule->var),
1290 				   r->count, r->ranges, r->mask);
1291 }
1292 
1293 
1294 /**
1295  * snd_pcm_hw_constraint_ranges - apply list of range constraints to a parameter
1296  * @runtime: PCM runtime instance
1297  * @cond: condition bits
1298  * @var: hw_params variable to apply the list of range constraints
1299  * @r: ranges
1300  *
1301  * Apply the list of range constraints to an interval parameter.
1302  *
1303  * Return: Zero if successful, or a negative error code on failure.
1304  */
1305 int snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime *runtime,
1306 				 unsigned int cond,
1307 				 snd_pcm_hw_param_t var,
1308 				 const struct snd_pcm_hw_constraint_ranges *r)
1309 {
1310 	return snd_pcm_hw_rule_add(runtime, cond, var,
1311 				   snd_pcm_hw_rule_ranges, (void *)r,
1312 				   var, -1);
1313 }
1314 EXPORT_SYMBOL(snd_pcm_hw_constraint_ranges);
1315 
1316 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1317 				   struct snd_pcm_hw_rule *rule)
1318 {
1319 	const struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1320 	unsigned int num = 0, den = 0;
1321 	int err;
1322 	err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1323 				  r->nrats, r->rats, &num, &den);
1324 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1325 		params->rate_num = num;
1326 		params->rate_den = den;
1327 	}
1328 	return err;
1329 }
1330 
1331 /**
1332  * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1333  * @runtime: PCM runtime instance
1334  * @cond: condition bits
1335  * @var: hw_params variable to apply the ratnums constraint
1336  * @r: struct snd_ratnums constriants
1337  *
1338  * Return: Zero if successful, or a negative error code on failure.
1339  */
1340 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1341 				  unsigned int cond,
1342 				  snd_pcm_hw_param_t var,
1343 				  const struct snd_pcm_hw_constraint_ratnums *r)
1344 {
1345 	return snd_pcm_hw_rule_add(runtime, cond, var,
1346 				   snd_pcm_hw_rule_ratnums, (void *)r,
1347 				   var, -1);
1348 }
1349 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1350 
1351 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1352 				   struct snd_pcm_hw_rule *rule)
1353 {
1354 	const struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1355 	unsigned int num = 0, den = 0;
1356 	int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1357 				  r->nrats, r->rats, &num, &den);
1358 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1359 		params->rate_num = num;
1360 		params->rate_den = den;
1361 	}
1362 	return err;
1363 }
1364 
1365 /**
1366  * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1367  * @runtime: PCM runtime instance
1368  * @cond: condition bits
1369  * @var: hw_params variable to apply the ratdens constraint
1370  * @r: struct snd_ratdens constriants
1371  *
1372  * Return: Zero if successful, or a negative error code on failure.
1373  */
1374 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1375 				  unsigned int cond,
1376 				  snd_pcm_hw_param_t var,
1377 				  const struct snd_pcm_hw_constraint_ratdens *r)
1378 {
1379 	return snd_pcm_hw_rule_add(runtime, cond, var,
1380 				   snd_pcm_hw_rule_ratdens, (void *)r,
1381 				   var, -1);
1382 }
1383 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1384 
1385 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1386 				  struct snd_pcm_hw_rule *rule)
1387 {
1388 	unsigned int l = (unsigned long) rule->private;
1389 	int width = l & 0xffff;
1390 	unsigned int msbits = l >> 16;
1391 	const struct snd_interval *i =
1392 		hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1393 
1394 	if (!snd_interval_single(i))
1395 		return 0;
1396 
1397 	if ((snd_interval_value(i) == width) ||
1398 	    (width == 0 && snd_interval_value(i) > msbits))
1399 		params->msbits = min_not_zero(params->msbits, msbits);
1400 
1401 	return 0;
1402 }
1403 
1404 /**
1405  * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1406  * @runtime: PCM runtime instance
1407  * @cond: condition bits
1408  * @width: sample bits width
1409  * @msbits: msbits width
1410  *
1411  * This constraint will set the number of most significant bits (msbits) if a
1412  * sample format with the specified width has been select. If width is set to 0
1413  * the msbits will be set for any sample format with a width larger than the
1414  * specified msbits.
1415  *
1416  * Return: Zero if successful, or a negative error code on failure.
1417  */
1418 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1419 				 unsigned int cond,
1420 				 unsigned int width,
1421 				 unsigned int msbits)
1422 {
1423 	unsigned long l = (msbits << 16) | width;
1424 	return snd_pcm_hw_rule_add(runtime, cond, -1,
1425 				    snd_pcm_hw_rule_msbits,
1426 				    (void*) l,
1427 				    SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1428 }
1429 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1430 
1431 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1432 				struct snd_pcm_hw_rule *rule)
1433 {
1434 	unsigned long step = (unsigned long) rule->private;
1435 	return snd_interval_step(hw_param_interval(params, rule->var), step);
1436 }
1437 
1438 /**
1439  * snd_pcm_hw_constraint_step - add a hw constraint step rule
1440  * @runtime: PCM runtime instance
1441  * @cond: condition bits
1442  * @var: hw_params variable to apply the step constraint
1443  * @step: step size
1444  *
1445  * Return: Zero if successful, or a negative error code on failure.
1446  */
1447 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1448 			       unsigned int cond,
1449 			       snd_pcm_hw_param_t var,
1450 			       unsigned long step)
1451 {
1452 	return snd_pcm_hw_rule_add(runtime, cond, var,
1453 				   snd_pcm_hw_rule_step, (void *) step,
1454 				   var, -1);
1455 }
1456 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1457 
1458 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1459 {
1460 	static unsigned int pow2_sizes[] = {
1461 		1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1462 		1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1463 		1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1464 		1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1465 	};
1466 	return snd_interval_list(hw_param_interval(params, rule->var),
1467 				 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1468 }
1469 
1470 /**
1471  * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1472  * @runtime: PCM runtime instance
1473  * @cond: condition bits
1474  * @var: hw_params variable to apply the power-of-2 constraint
1475  *
1476  * Return: Zero if successful, or a negative error code on failure.
1477  */
1478 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1479 			       unsigned int cond,
1480 			       snd_pcm_hw_param_t var)
1481 {
1482 	return snd_pcm_hw_rule_add(runtime, cond, var,
1483 				   snd_pcm_hw_rule_pow2, NULL,
1484 				   var, -1);
1485 }
1486 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1487 
1488 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1489 					   struct snd_pcm_hw_rule *rule)
1490 {
1491 	unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1492 	struct snd_interval *rate;
1493 
1494 	rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1495 	return snd_interval_list(rate, 1, &base_rate, 0);
1496 }
1497 
1498 /**
1499  * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1500  * @runtime: PCM runtime instance
1501  * @base_rate: the rate at which the hardware does not resample
1502  *
1503  * Return: Zero if successful, or a negative error code on failure.
1504  */
1505 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1506 			       unsigned int base_rate)
1507 {
1508 	return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1509 				   SNDRV_PCM_HW_PARAM_RATE,
1510 				   snd_pcm_hw_rule_noresample_func,
1511 				   (void *)(uintptr_t)base_rate,
1512 				   SNDRV_PCM_HW_PARAM_RATE, -1);
1513 }
1514 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1515 
1516 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1517 				  snd_pcm_hw_param_t var)
1518 {
1519 	if (hw_is_mask(var)) {
1520 		snd_mask_any(hw_param_mask(params, var));
1521 		params->cmask |= 1 << var;
1522 		params->rmask |= 1 << var;
1523 		return;
1524 	}
1525 	if (hw_is_interval(var)) {
1526 		snd_interval_any(hw_param_interval(params, var));
1527 		params->cmask |= 1 << var;
1528 		params->rmask |= 1 << var;
1529 		return;
1530 	}
1531 	snd_BUG();
1532 }
1533 
1534 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1535 {
1536 	unsigned int k;
1537 	memset(params, 0, sizeof(*params));
1538 	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1539 		_snd_pcm_hw_param_any(params, k);
1540 	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1541 		_snd_pcm_hw_param_any(params, k);
1542 	params->info = ~0U;
1543 }
1544 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1545 
1546 /**
1547  * snd_pcm_hw_param_value - return @params field @var value
1548  * @params: the hw_params instance
1549  * @var: parameter to retrieve
1550  * @dir: pointer to the direction (-1,0,1) or %NULL
1551  *
1552  * Return: The value for field @var if it's fixed in configuration space
1553  * defined by @params. -%EINVAL otherwise.
1554  */
1555 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1556 			   snd_pcm_hw_param_t var, int *dir)
1557 {
1558 	if (hw_is_mask(var)) {
1559 		const struct snd_mask *mask = hw_param_mask_c(params, var);
1560 		if (!snd_mask_single(mask))
1561 			return -EINVAL;
1562 		if (dir)
1563 			*dir = 0;
1564 		return snd_mask_value(mask);
1565 	}
1566 	if (hw_is_interval(var)) {
1567 		const struct snd_interval *i = hw_param_interval_c(params, var);
1568 		if (!snd_interval_single(i))
1569 			return -EINVAL;
1570 		if (dir)
1571 			*dir = i->openmin;
1572 		return snd_interval_value(i);
1573 	}
1574 	return -EINVAL;
1575 }
1576 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1577 
1578 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1579 				snd_pcm_hw_param_t var)
1580 {
1581 	if (hw_is_mask(var)) {
1582 		snd_mask_none(hw_param_mask(params, var));
1583 		params->cmask |= 1 << var;
1584 		params->rmask |= 1 << var;
1585 	} else if (hw_is_interval(var)) {
1586 		snd_interval_none(hw_param_interval(params, var));
1587 		params->cmask |= 1 << var;
1588 		params->rmask |= 1 << var;
1589 	} else {
1590 		snd_BUG();
1591 	}
1592 }
1593 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1594 
1595 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1596 				   snd_pcm_hw_param_t var)
1597 {
1598 	int changed;
1599 	if (hw_is_mask(var))
1600 		changed = snd_mask_refine_first(hw_param_mask(params, var));
1601 	else if (hw_is_interval(var))
1602 		changed = snd_interval_refine_first(hw_param_interval(params, var));
1603 	else
1604 		return -EINVAL;
1605 	if (changed > 0) {
1606 		params->cmask |= 1 << var;
1607 		params->rmask |= 1 << var;
1608 	}
1609 	return changed;
1610 }
1611 
1612 
1613 /**
1614  * snd_pcm_hw_param_first - refine config space and return minimum value
1615  * @pcm: PCM instance
1616  * @params: the hw_params instance
1617  * @var: parameter to retrieve
1618  * @dir: pointer to the direction (-1,0,1) or %NULL
1619  *
1620  * Inside configuration space defined by @params remove from @var all
1621  * values > minimum. Reduce configuration space accordingly.
1622  *
1623  * Return: The minimum, or a negative error code on failure.
1624  */
1625 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1626 			   struct snd_pcm_hw_params *params,
1627 			   snd_pcm_hw_param_t var, int *dir)
1628 {
1629 	int changed = _snd_pcm_hw_param_first(params, var);
1630 	if (changed < 0)
1631 		return changed;
1632 	if (params->rmask) {
1633 		int err = snd_pcm_hw_refine(pcm, params);
1634 		if (err < 0)
1635 			return err;
1636 	}
1637 	return snd_pcm_hw_param_value(params, var, dir);
1638 }
1639 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1640 
1641 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1642 				  snd_pcm_hw_param_t var)
1643 {
1644 	int changed;
1645 	if (hw_is_mask(var))
1646 		changed = snd_mask_refine_last(hw_param_mask(params, var));
1647 	else if (hw_is_interval(var))
1648 		changed = snd_interval_refine_last(hw_param_interval(params, var));
1649 	else
1650 		return -EINVAL;
1651 	if (changed > 0) {
1652 		params->cmask |= 1 << var;
1653 		params->rmask |= 1 << var;
1654 	}
1655 	return changed;
1656 }
1657 
1658 
1659 /**
1660  * snd_pcm_hw_param_last - refine config space and return maximum value
1661  * @pcm: PCM instance
1662  * @params: the hw_params instance
1663  * @var: parameter to retrieve
1664  * @dir: pointer to the direction (-1,0,1) or %NULL
1665  *
1666  * Inside configuration space defined by @params remove from @var all
1667  * values < maximum. Reduce configuration space accordingly.
1668  *
1669  * Return: The maximum, or a negative error code on failure.
1670  */
1671 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1672 			  struct snd_pcm_hw_params *params,
1673 			  snd_pcm_hw_param_t var, int *dir)
1674 {
1675 	int changed = _snd_pcm_hw_param_last(params, var);
1676 	if (changed < 0)
1677 		return changed;
1678 	if (params->rmask) {
1679 		int err = snd_pcm_hw_refine(pcm, params);
1680 		if (err < 0)
1681 			return err;
1682 	}
1683 	return snd_pcm_hw_param_value(params, var, dir);
1684 }
1685 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1686 
1687 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1688 				   void *arg)
1689 {
1690 	struct snd_pcm_runtime *runtime = substream->runtime;
1691 	unsigned long flags;
1692 	snd_pcm_stream_lock_irqsave(substream, flags);
1693 	if (snd_pcm_running(substream) &&
1694 	    snd_pcm_update_hw_ptr(substream) >= 0)
1695 		runtime->status->hw_ptr %= runtime->buffer_size;
1696 	else {
1697 		runtime->status->hw_ptr = 0;
1698 		runtime->hw_ptr_wrap = 0;
1699 	}
1700 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1701 	return 0;
1702 }
1703 
1704 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1705 					  void *arg)
1706 {
1707 	struct snd_pcm_channel_info *info = arg;
1708 	struct snd_pcm_runtime *runtime = substream->runtime;
1709 	int width;
1710 	if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1711 		info->offset = -1;
1712 		return 0;
1713 	}
1714 	width = snd_pcm_format_physical_width(runtime->format);
1715 	if (width < 0)
1716 		return width;
1717 	info->offset = 0;
1718 	switch (runtime->access) {
1719 	case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1720 	case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1721 		info->first = info->channel * width;
1722 		info->step = runtime->channels * width;
1723 		break;
1724 	case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1725 	case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1726 	{
1727 		size_t size = runtime->dma_bytes / runtime->channels;
1728 		info->first = info->channel * size * 8;
1729 		info->step = width;
1730 		break;
1731 	}
1732 	default:
1733 		snd_BUG();
1734 		break;
1735 	}
1736 	return 0;
1737 }
1738 
1739 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1740 				       void *arg)
1741 {
1742 	struct snd_pcm_hw_params *params = arg;
1743 	snd_pcm_format_t format;
1744 	int channels;
1745 	ssize_t frame_size;
1746 
1747 	params->fifo_size = substream->runtime->hw.fifo_size;
1748 	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1749 		format = params_format(params);
1750 		channels = params_channels(params);
1751 		frame_size = snd_pcm_format_size(format, channels);
1752 		if (frame_size > 0)
1753 			params->fifo_size /= (unsigned)frame_size;
1754 	}
1755 	return 0;
1756 }
1757 
1758 /**
1759  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1760  * @substream: the pcm substream instance
1761  * @cmd: ioctl command
1762  * @arg: ioctl argument
1763  *
1764  * Processes the generic ioctl commands for PCM.
1765  * Can be passed as the ioctl callback for PCM ops.
1766  *
1767  * Return: Zero if successful, or a negative error code on failure.
1768  */
1769 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1770 		      unsigned int cmd, void *arg)
1771 {
1772 	switch (cmd) {
1773 	case SNDRV_PCM_IOCTL1_RESET:
1774 		return snd_pcm_lib_ioctl_reset(substream, arg);
1775 	case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1776 		return snd_pcm_lib_ioctl_channel_info(substream, arg);
1777 	case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1778 		return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1779 	}
1780 	return -ENXIO;
1781 }
1782 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1783 
1784 /**
1785  * snd_pcm_period_elapsed - update the pcm status for the next period
1786  * @substream: the pcm substream instance
1787  *
1788  * This function is called from the interrupt handler when the
1789  * PCM has processed the period size.  It will update the current
1790  * pointer, wake up sleepers, etc.
1791  *
1792  * Even if more than one periods have elapsed since the last call, you
1793  * have to call this only once.
1794  */
1795 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1796 {
1797 	struct snd_pcm_runtime *runtime;
1798 	unsigned long flags;
1799 
1800 	if (PCM_RUNTIME_CHECK(substream))
1801 		return;
1802 	runtime = substream->runtime;
1803 
1804 	snd_pcm_stream_lock_irqsave(substream, flags);
1805 	if (!snd_pcm_running(substream) ||
1806 	    snd_pcm_update_hw_ptr0(substream, 1) < 0)
1807 		goto _end;
1808 
1809 #ifdef CONFIG_SND_PCM_TIMER
1810 	if (substream->timer_running)
1811 		snd_timer_interrupt(substream->timer, 1);
1812 #endif
1813  _end:
1814 	kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1815 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1816 }
1817 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1818 
1819 /*
1820  * Wait until avail_min data becomes available
1821  * Returns a negative error code if any error occurs during operation.
1822  * The available space is stored on availp.  When err = 0 and avail = 0
1823  * on the capture stream, it indicates the stream is in DRAINING state.
1824  */
1825 static int wait_for_avail(struct snd_pcm_substream *substream,
1826 			      snd_pcm_uframes_t *availp)
1827 {
1828 	struct snd_pcm_runtime *runtime = substream->runtime;
1829 	int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1830 	wait_queue_entry_t wait;
1831 	int err = 0;
1832 	snd_pcm_uframes_t avail = 0;
1833 	long wait_time, tout;
1834 
1835 	init_waitqueue_entry(&wait, current);
1836 	set_current_state(TASK_INTERRUPTIBLE);
1837 	add_wait_queue(&runtime->tsleep, &wait);
1838 
1839 	if (runtime->no_period_wakeup)
1840 		wait_time = MAX_SCHEDULE_TIMEOUT;
1841 	else {
1842 		/* use wait time from substream if available */
1843 		if (substream->wait_time) {
1844 			wait_time = substream->wait_time;
1845 		} else {
1846 			wait_time = 10;
1847 
1848 			if (runtime->rate) {
1849 				long t = runtime->period_size * 2 /
1850 					 runtime->rate;
1851 				wait_time = max(t, wait_time);
1852 			}
1853 			wait_time = msecs_to_jiffies(wait_time * 1000);
1854 		}
1855 	}
1856 
1857 	for (;;) {
1858 		if (signal_pending(current)) {
1859 			err = -ERESTARTSYS;
1860 			break;
1861 		}
1862 
1863 		/*
1864 		 * We need to check if space became available already
1865 		 * (and thus the wakeup happened already) first to close
1866 		 * the race of space already having become available.
1867 		 * This check must happen after been added to the waitqueue
1868 		 * and having current state be INTERRUPTIBLE.
1869 		 */
1870 		avail = snd_pcm_avail(substream);
1871 		if (avail >= runtime->twake)
1872 			break;
1873 		snd_pcm_stream_unlock_irq(substream);
1874 
1875 		tout = schedule_timeout(wait_time);
1876 
1877 		snd_pcm_stream_lock_irq(substream);
1878 		set_current_state(TASK_INTERRUPTIBLE);
1879 		switch (runtime->status->state) {
1880 		case SNDRV_PCM_STATE_SUSPENDED:
1881 			err = -ESTRPIPE;
1882 			goto _endloop;
1883 		case SNDRV_PCM_STATE_XRUN:
1884 			err = -EPIPE;
1885 			goto _endloop;
1886 		case SNDRV_PCM_STATE_DRAINING:
1887 			if (is_playback)
1888 				err = -EPIPE;
1889 			else
1890 				avail = 0; /* indicate draining */
1891 			goto _endloop;
1892 		case SNDRV_PCM_STATE_OPEN:
1893 		case SNDRV_PCM_STATE_SETUP:
1894 		case SNDRV_PCM_STATE_DISCONNECTED:
1895 			err = -EBADFD;
1896 			goto _endloop;
1897 		case SNDRV_PCM_STATE_PAUSED:
1898 			continue;
1899 		}
1900 		if (!tout) {
1901 			pcm_dbg(substream->pcm,
1902 				"%s write error (DMA or IRQ trouble?)\n",
1903 				is_playback ? "playback" : "capture");
1904 			err = -EIO;
1905 			break;
1906 		}
1907 	}
1908  _endloop:
1909 	set_current_state(TASK_RUNNING);
1910 	remove_wait_queue(&runtime->tsleep, &wait);
1911 	*availp = avail;
1912 	return err;
1913 }
1914 
1915 typedef int (*pcm_transfer_f)(struct snd_pcm_substream *substream,
1916 			      int channel, unsigned long hwoff,
1917 			      void *buf, unsigned long bytes);
1918 
1919 typedef int (*pcm_copy_f)(struct snd_pcm_substream *, snd_pcm_uframes_t, void *,
1920 			  snd_pcm_uframes_t, snd_pcm_uframes_t, pcm_transfer_f);
1921 
1922 /* calculate the target DMA-buffer position to be written/read */
1923 static void *get_dma_ptr(struct snd_pcm_runtime *runtime,
1924 			   int channel, unsigned long hwoff)
1925 {
1926 	return runtime->dma_area + hwoff +
1927 		channel * (runtime->dma_bytes / runtime->channels);
1928 }
1929 
1930 /* default copy_user ops for write; used for both interleaved and non- modes */
1931 static int default_write_copy(struct snd_pcm_substream *substream,
1932 			      int channel, unsigned long hwoff,
1933 			      void *buf, unsigned long bytes)
1934 {
1935 	if (copy_from_user(get_dma_ptr(substream->runtime, channel, hwoff),
1936 			   (void __user *)buf, bytes))
1937 		return -EFAULT;
1938 	return 0;
1939 }
1940 
1941 /* default copy_kernel ops for write */
1942 static int default_write_copy_kernel(struct snd_pcm_substream *substream,
1943 				     int channel, unsigned long hwoff,
1944 				     void *buf, unsigned long bytes)
1945 {
1946 	memcpy(get_dma_ptr(substream->runtime, channel, hwoff), buf, bytes);
1947 	return 0;
1948 }
1949 
1950 /* fill silence instead of copy data; called as a transfer helper
1951  * from __snd_pcm_lib_write() or directly from noninterleaved_copy() when
1952  * a NULL buffer is passed
1953  */
1954 static int fill_silence(struct snd_pcm_substream *substream, int channel,
1955 			unsigned long hwoff, void *buf, unsigned long bytes)
1956 {
1957 	struct snd_pcm_runtime *runtime = substream->runtime;
1958 
1959 	if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
1960 		return 0;
1961 	if (substream->ops->fill_silence)
1962 		return substream->ops->fill_silence(substream, channel,
1963 						    hwoff, bytes);
1964 
1965 	snd_pcm_format_set_silence(runtime->format,
1966 				   get_dma_ptr(runtime, channel, hwoff),
1967 				   bytes_to_samples(runtime, bytes));
1968 	return 0;
1969 }
1970 
1971 /* default copy_user ops for read; used for both interleaved and non- modes */
1972 static int default_read_copy(struct snd_pcm_substream *substream,
1973 			     int channel, unsigned long hwoff,
1974 			     void *buf, unsigned long bytes)
1975 {
1976 	if (copy_to_user((void __user *)buf,
1977 			 get_dma_ptr(substream->runtime, channel, hwoff),
1978 			 bytes))
1979 		return -EFAULT;
1980 	return 0;
1981 }
1982 
1983 /* default copy_kernel ops for read */
1984 static int default_read_copy_kernel(struct snd_pcm_substream *substream,
1985 				    int channel, unsigned long hwoff,
1986 				    void *buf, unsigned long bytes)
1987 {
1988 	memcpy(buf, get_dma_ptr(substream->runtime, channel, hwoff), bytes);
1989 	return 0;
1990 }
1991 
1992 /* call transfer function with the converted pointers and sizes;
1993  * for interleaved mode, it's one shot for all samples
1994  */
1995 static int interleaved_copy(struct snd_pcm_substream *substream,
1996 			    snd_pcm_uframes_t hwoff, void *data,
1997 			    snd_pcm_uframes_t off,
1998 			    snd_pcm_uframes_t frames,
1999 			    pcm_transfer_f transfer)
2000 {
2001 	struct snd_pcm_runtime *runtime = substream->runtime;
2002 
2003 	/* convert to bytes */
2004 	hwoff = frames_to_bytes(runtime, hwoff);
2005 	off = frames_to_bytes(runtime, off);
2006 	frames = frames_to_bytes(runtime, frames);
2007 	return transfer(substream, 0, hwoff, data + off, frames);
2008 }
2009 
2010 /* call transfer function with the converted pointers and sizes for each
2011  * non-interleaved channel; when buffer is NULL, silencing instead of copying
2012  */
2013 static int noninterleaved_copy(struct snd_pcm_substream *substream,
2014 			       snd_pcm_uframes_t hwoff, void *data,
2015 			       snd_pcm_uframes_t off,
2016 			       snd_pcm_uframes_t frames,
2017 			       pcm_transfer_f transfer)
2018 {
2019 	struct snd_pcm_runtime *runtime = substream->runtime;
2020 	int channels = runtime->channels;
2021 	void **bufs = data;
2022 	int c, err;
2023 
2024 	/* convert to bytes; note that it's not frames_to_bytes() here.
2025 	 * in non-interleaved mode, we copy for each channel, thus
2026 	 * each copy is n_samples bytes x channels = whole frames.
2027 	 */
2028 	off = samples_to_bytes(runtime, off);
2029 	frames = samples_to_bytes(runtime, frames);
2030 	hwoff = samples_to_bytes(runtime, hwoff);
2031 	for (c = 0; c < channels; ++c, ++bufs) {
2032 		if (!data || !*bufs)
2033 			err = fill_silence(substream, c, hwoff, NULL, frames);
2034 		else
2035 			err = transfer(substream, c, hwoff, *bufs + off,
2036 				       frames);
2037 		if (err < 0)
2038 			return err;
2039 	}
2040 	return 0;
2041 }
2042 
2043 /* fill silence on the given buffer position;
2044  * called from snd_pcm_playback_silence()
2045  */
2046 static int fill_silence_frames(struct snd_pcm_substream *substream,
2047 			       snd_pcm_uframes_t off, snd_pcm_uframes_t frames)
2048 {
2049 	if (substream->runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
2050 	    substream->runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED)
2051 		return interleaved_copy(substream, off, NULL, 0, frames,
2052 					fill_silence);
2053 	else
2054 		return noninterleaved_copy(substream, off, NULL, 0, frames,
2055 					   fill_silence);
2056 }
2057 
2058 /* sanity-check for read/write methods */
2059 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2060 {
2061 	struct snd_pcm_runtime *runtime;
2062 	if (PCM_RUNTIME_CHECK(substream))
2063 		return -ENXIO;
2064 	runtime = substream->runtime;
2065 	if (snd_BUG_ON(!substream->ops->copy_user && !runtime->dma_area))
2066 		return -EINVAL;
2067 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2068 		return -EBADFD;
2069 	return 0;
2070 }
2071 
2072 static int pcm_accessible_state(struct snd_pcm_runtime *runtime)
2073 {
2074 	switch (runtime->status->state) {
2075 	case SNDRV_PCM_STATE_PREPARED:
2076 	case SNDRV_PCM_STATE_RUNNING:
2077 	case SNDRV_PCM_STATE_PAUSED:
2078 		return 0;
2079 	case SNDRV_PCM_STATE_XRUN:
2080 		return -EPIPE;
2081 	case SNDRV_PCM_STATE_SUSPENDED:
2082 		return -ESTRPIPE;
2083 	default:
2084 		return -EBADFD;
2085 	}
2086 }
2087 
2088 /* update to the given appl_ptr and call ack callback if needed;
2089  * when an error is returned, take back to the original value
2090  */
2091 int pcm_lib_apply_appl_ptr(struct snd_pcm_substream *substream,
2092 			   snd_pcm_uframes_t appl_ptr)
2093 {
2094 	struct snd_pcm_runtime *runtime = substream->runtime;
2095 	snd_pcm_uframes_t old_appl_ptr = runtime->control->appl_ptr;
2096 	int ret;
2097 
2098 	if (old_appl_ptr == appl_ptr)
2099 		return 0;
2100 
2101 	runtime->control->appl_ptr = appl_ptr;
2102 	if (substream->ops->ack) {
2103 		ret = substream->ops->ack(substream);
2104 		if (ret < 0) {
2105 			runtime->control->appl_ptr = old_appl_ptr;
2106 			return ret;
2107 		}
2108 	}
2109 
2110 	trace_applptr(substream, old_appl_ptr, appl_ptr);
2111 
2112 	return 0;
2113 }
2114 
2115 /* the common loop for read/write data */
2116 snd_pcm_sframes_t __snd_pcm_lib_xfer(struct snd_pcm_substream *substream,
2117 				     void *data, bool interleaved,
2118 				     snd_pcm_uframes_t size, bool in_kernel)
2119 {
2120 	struct snd_pcm_runtime *runtime = substream->runtime;
2121 	snd_pcm_uframes_t xfer = 0;
2122 	snd_pcm_uframes_t offset = 0;
2123 	snd_pcm_uframes_t avail;
2124 	pcm_copy_f writer;
2125 	pcm_transfer_f transfer;
2126 	bool nonblock;
2127 	bool is_playback;
2128 	int err;
2129 
2130 	err = pcm_sanity_check(substream);
2131 	if (err < 0)
2132 		return err;
2133 
2134 	is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
2135 	if (interleaved) {
2136 		if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2137 		    runtime->channels > 1)
2138 			return -EINVAL;
2139 		writer = interleaved_copy;
2140 	} else {
2141 		if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2142 			return -EINVAL;
2143 		writer = noninterleaved_copy;
2144 	}
2145 
2146 	if (!data) {
2147 		if (is_playback)
2148 			transfer = fill_silence;
2149 		else
2150 			return -EINVAL;
2151 	} else if (in_kernel) {
2152 		if (substream->ops->copy_kernel)
2153 			transfer = substream->ops->copy_kernel;
2154 		else
2155 			transfer = is_playback ?
2156 				default_write_copy_kernel : default_read_copy_kernel;
2157 	} else {
2158 		if (substream->ops->copy_user)
2159 			transfer = (pcm_transfer_f)substream->ops->copy_user;
2160 		else
2161 			transfer = is_playback ?
2162 				default_write_copy : default_read_copy;
2163 	}
2164 
2165 	if (size == 0)
2166 		return 0;
2167 
2168 	nonblock = !!(substream->f_flags & O_NONBLOCK);
2169 
2170 	snd_pcm_stream_lock_irq(substream);
2171 	err = pcm_accessible_state(runtime);
2172 	if (err < 0)
2173 		goto _end_unlock;
2174 
2175 	runtime->twake = runtime->control->avail_min ? : 1;
2176 	if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2177 		snd_pcm_update_hw_ptr(substream);
2178 
2179 	if (!is_playback &&
2180 	    runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2181 	    size >= runtime->start_threshold) {
2182 		err = snd_pcm_start(substream);
2183 		if (err < 0)
2184 			goto _end_unlock;
2185 	}
2186 
2187 	avail = snd_pcm_avail(substream);
2188 
2189 	while (size > 0) {
2190 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2191 		snd_pcm_uframes_t cont;
2192 		if (!avail) {
2193 			if (!is_playback &&
2194 			    runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
2195 				snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2196 				goto _end_unlock;
2197 			}
2198 			if (nonblock) {
2199 				err = -EAGAIN;
2200 				goto _end_unlock;
2201 			}
2202 			runtime->twake = min_t(snd_pcm_uframes_t, size,
2203 					runtime->control->avail_min ? : 1);
2204 			err = wait_for_avail(substream, &avail);
2205 			if (err < 0)
2206 				goto _end_unlock;
2207 			if (!avail)
2208 				continue; /* draining */
2209 		}
2210 		frames = size > avail ? avail : size;
2211 		appl_ptr = READ_ONCE(runtime->control->appl_ptr);
2212 		appl_ofs = appl_ptr % runtime->buffer_size;
2213 		cont = runtime->buffer_size - appl_ofs;
2214 		if (frames > cont)
2215 			frames = cont;
2216 		if (snd_BUG_ON(!frames)) {
2217 			runtime->twake = 0;
2218 			snd_pcm_stream_unlock_irq(substream);
2219 			return -EINVAL;
2220 		}
2221 		snd_pcm_stream_unlock_irq(substream);
2222 		err = writer(substream, appl_ofs, data, offset, frames,
2223 			     transfer);
2224 		snd_pcm_stream_lock_irq(substream);
2225 		if (err < 0)
2226 			goto _end_unlock;
2227 		err = pcm_accessible_state(runtime);
2228 		if (err < 0)
2229 			goto _end_unlock;
2230 		appl_ptr += frames;
2231 		if (appl_ptr >= runtime->boundary)
2232 			appl_ptr -= runtime->boundary;
2233 		err = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2234 		if (err < 0)
2235 			goto _end_unlock;
2236 
2237 		offset += frames;
2238 		size -= frames;
2239 		xfer += frames;
2240 		avail -= frames;
2241 		if (is_playback &&
2242 		    runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2243 		    snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2244 			err = snd_pcm_start(substream);
2245 			if (err < 0)
2246 				goto _end_unlock;
2247 		}
2248 	}
2249  _end_unlock:
2250 	runtime->twake = 0;
2251 	if (xfer > 0 && err >= 0)
2252 		snd_pcm_update_state(substream, runtime);
2253 	snd_pcm_stream_unlock_irq(substream);
2254 	return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2255 }
2256 EXPORT_SYMBOL(__snd_pcm_lib_xfer);
2257 
2258 /*
2259  * standard channel mapping helpers
2260  */
2261 
2262 /* default channel maps for multi-channel playbacks, up to 8 channels */
2263 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2264 	{ .channels = 1,
2265 	  .map = { SNDRV_CHMAP_MONO } },
2266 	{ .channels = 2,
2267 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2268 	{ .channels = 4,
2269 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2270 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2271 	{ .channels = 6,
2272 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2273 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2274 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2275 	{ .channels = 8,
2276 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2277 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2278 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2279 		   SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2280 	{ }
2281 };
2282 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2283 
2284 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2285 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2286 	{ .channels = 1,
2287 	  .map = { SNDRV_CHMAP_MONO } },
2288 	{ .channels = 2,
2289 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2290 	{ .channels = 4,
2291 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2292 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2293 	{ .channels = 6,
2294 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2295 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2296 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2297 	{ .channels = 8,
2298 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2299 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2300 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2301 		   SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2302 	{ }
2303 };
2304 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2305 
2306 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2307 {
2308 	if (ch > info->max_channels)
2309 		return false;
2310 	return !info->channel_mask || (info->channel_mask & (1U << ch));
2311 }
2312 
2313 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2314 			      struct snd_ctl_elem_info *uinfo)
2315 {
2316 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2317 
2318 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2319 	uinfo->count = 0;
2320 	uinfo->count = info->max_channels;
2321 	uinfo->value.integer.min = 0;
2322 	uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2323 	return 0;
2324 }
2325 
2326 /* get callback for channel map ctl element
2327  * stores the channel position firstly matching with the current channels
2328  */
2329 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2330 			     struct snd_ctl_elem_value *ucontrol)
2331 {
2332 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2333 	unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2334 	struct snd_pcm_substream *substream;
2335 	const struct snd_pcm_chmap_elem *map;
2336 
2337 	if (!info->chmap)
2338 		return -EINVAL;
2339 	substream = snd_pcm_chmap_substream(info, idx);
2340 	if (!substream)
2341 		return -ENODEV;
2342 	memset(ucontrol->value.integer.value, 0,
2343 	       sizeof(ucontrol->value.integer.value));
2344 	if (!substream->runtime)
2345 		return 0; /* no channels set */
2346 	for (map = info->chmap; map->channels; map++) {
2347 		int i;
2348 		if (map->channels == substream->runtime->channels &&
2349 		    valid_chmap_channels(info, map->channels)) {
2350 			for (i = 0; i < map->channels; i++)
2351 				ucontrol->value.integer.value[i] = map->map[i];
2352 			return 0;
2353 		}
2354 	}
2355 	return -EINVAL;
2356 }
2357 
2358 /* tlv callback for channel map ctl element
2359  * expands the pre-defined channel maps in a form of TLV
2360  */
2361 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2362 			     unsigned int size, unsigned int __user *tlv)
2363 {
2364 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2365 	const struct snd_pcm_chmap_elem *map;
2366 	unsigned int __user *dst;
2367 	int c, count = 0;
2368 
2369 	if (!info->chmap)
2370 		return -EINVAL;
2371 	if (size < 8)
2372 		return -ENOMEM;
2373 	if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2374 		return -EFAULT;
2375 	size -= 8;
2376 	dst = tlv + 2;
2377 	for (map = info->chmap; map->channels; map++) {
2378 		int chs_bytes = map->channels * 4;
2379 		if (!valid_chmap_channels(info, map->channels))
2380 			continue;
2381 		if (size < 8)
2382 			return -ENOMEM;
2383 		if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2384 		    put_user(chs_bytes, dst + 1))
2385 			return -EFAULT;
2386 		dst += 2;
2387 		size -= 8;
2388 		count += 8;
2389 		if (size < chs_bytes)
2390 			return -ENOMEM;
2391 		size -= chs_bytes;
2392 		count += chs_bytes;
2393 		for (c = 0; c < map->channels; c++) {
2394 			if (put_user(map->map[c], dst))
2395 				return -EFAULT;
2396 			dst++;
2397 		}
2398 	}
2399 	if (put_user(count, tlv + 1))
2400 		return -EFAULT;
2401 	return 0;
2402 }
2403 
2404 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2405 {
2406 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2407 	info->pcm->streams[info->stream].chmap_kctl = NULL;
2408 	kfree(info);
2409 }
2410 
2411 /**
2412  * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2413  * @pcm: the assigned PCM instance
2414  * @stream: stream direction
2415  * @chmap: channel map elements (for query)
2416  * @max_channels: the max number of channels for the stream
2417  * @private_value: the value passed to each kcontrol's private_value field
2418  * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2419  *
2420  * Create channel-mapping control elements assigned to the given PCM stream(s).
2421  * Return: Zero if successful, or a negative error value.
2422  */
2423 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2424 			   const struct snd_pcm_chmap_elem *chmap,
2425 			   int max_channels,
2426 			   unsigned long private_value,
2427 			   struct snd_pcm_chmap **info_ret)
2428 {
2429 	struct snd_pcm_chmap *info;
2430 	struct snd_kcontrol_new knew = {
2431 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
2432 		.access = SNDRV_CTL_ELEM_ACCESS_READ |
2433 			SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2434 			SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2435 		.info = pcm_chmap_ctl_info,
2436 		.get = pcm_chmap_ctl_get,
2437 		.tlv.c = pcm_chmap_ctl_tlv,
2438 	};
2439 	int err;
2440 
2441 	if (WARN_ON(pcm->streams[stream].chmap_kctl))
2442 		return -EBUSY;
2443 	info = kzalloc(sizeof(*info), GFP_KERNEL);
2444 	if (!info)
2445 		return -ENOMEM;
2446 	info->pcm = pcm;
2447 	info->stream = stream;
2448 	info->chmap = chmap;
2449 	info->max_channels = max_channels;
2450 	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2451 		knew.name = "Playback Channel Map";
2452 	else
2453 		knew.name = "Capture Channel Map";
2454 	knew.device = pcm->device;
2455 	knew.count = pcm->streams[stream].substream_count;
2456 	knew.private_value = private_value;
2457 	info->kctl = snd_ctl_new1(&knew, info);
2458 	if (!info->kctl) {
2459 		kfree(info);
2460 		return -ENOMEM;
2461 	}
2462 	info->kctl->private_free = pcm_chmap_ctl_private_free;
2463 	err = snd_ctl_add(pcm->card, info->kctl);
2464 	if (err < 0)
2465 		return err;
2466 	pcm->streams[stream].chmap_kctl = info->kctl;
2467 	if (info_ret)
2468 		*info_ret = info;
2469 	return 0;
2470 }
2471 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);
2472