2 * Digital Audio (PCM) abstract layer
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 * Abramo Bagnara <abramo@alsa-project.org>
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.
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.
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
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>
36 #include "pcm_local.h"
38 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
39 #define CREATE_TRACE_POINTS
40 #include "pcm_trace.h"
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)
48 static int fill_silence_frames(struct snd_pcm_substream *substream,
49 snd_pcm_uframes_t off, snd_pcm_uframes_t frames);
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
58 * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
60 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
62 struct snd_pcm_runtime *runtime = substream->runtime;
63 snd_pcm_uframes_t frames, ofs, transfer;
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;
72 n += runtime->boundary;
73 if ((snd_pcm_uframes_t)n < runtime->silence_filled)
74 runtime->silence_filled -= n;
76 runtime->silence_filled = 0;
77 runtime->silence_start = appl_ptr;
79 if (runtime->silence_filled >= runtime->buffer_size)
81 noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
82 if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
84 frames = runtime->silence_threshold - noise_dist;
85 if (frames > runtime->silence_size)
86 frames = runtime->silence_size;
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) %
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;
106 runtime->silence_start = ofs;
109 frames = runtime->buffer_size - runtime->silence_filled;
111 if (snd_BUG_ON(frames > runtime->buffer_size))
115 ofs = runtime->silence_start % runtime->buffer_size;
117 transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
118 err = fill_silence_frames(substream, ofs, transfer);
120 runtime->silence_filled += transfer;
126 #ifdef CONFIG_SND_DEBUG
127 void snd_pcm_debug_name(struct snd_pcm_substream *substream,
128 char *name, size_t len)
130 snprintf(name, len, "pcmC%dD%d%c:%d",
131 substream->pcm->card->number,
132 substream->pcm->device,
133 substream->stream ? 'c' : 'p',
136 EXPORT_SYMBOL(snd_pcm_debug_name);
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 */
143 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
145 #define xrun_debug(substream, mask) \
146 ((substream)->pstr->xrun_debug & (mask))
148 #define xrun_debug(substream, mask) 0
151 #define dump_stack_on_xrun(substream) do { \
152 if (xrun_debug(substream, XRUN_DEBUG_STACK)) \
156 /* call with stream lock held */
157 void __snd_pcm_xrun(struct snd_pcm_substream *substream)
159 struct snd_pcm_runtime *runtime = substream->runtime;
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)) {
167 snd_pcm_debug_name(substream, name, sizeof(name));
168 pcm_warn(substream->pcm, "XRUN: %s\n", name);
169 dump_stack_on_xrun(substream);
173 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
174 #define hw_ptr_error(substream, in_interrupt, reason, fmt, args...) \
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); \
184 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
186 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
190 int snd_pcm_update_state(struct snd_pcm_substream *substream,
191 struct snd_pcm_runtime *runtime)
193 snd_pcm_uframes_t avail;
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);
204 if (avail >= runtime->stop_threshold) {
205 __snd_pcm_xrun(substream);
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);
217 static void update_audio_tstamp(struct snd_pcm_substream *substream,
218 struct timespec *curr_tstamp,
219 struct timespec *audio_tstamp)
221 struct snd_pcm_runtime *runtime = substream->runtime;
222 u64 audio_frames, audio_nsecs;
223 struct timespec driver_tstamp;
225 if (runtime->tstamp_mode != SNDRV_PCM_TSTAMP_ENABLE)
228 if (!(substream->ops->get_time_info) ||
229 (runtime->audio_tstamp_report.actual_type ==
230 SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
233 * provide audio timestamp derived from pointer position
234 * add delay only if requested
237 audio_frames = runtime->hw_ptr_wrap + runtime->status->hw_ptr;
239 if (runtime->audio_tstamp_config.report_delay) {
240 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
241 audio_frames -= runtime->delay;
243 audio_frames += runtime->delay;
245 audio_nsecs = div_u64(audio_frames * 1000000000LL,
247 *audio_tstamp = ns_to_timespec(audio_nsecs);
249 if (!timespec_equal(&runtime->status->audio_tstamp, audio_tstamp)) {
250 runtime->status->audio_tstamp = *audio_tstamp;
251 runtime->status->tstamp = *curr_tstamp;
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
258 snd_pcm_gettime(substream->runtime, (struct timespec *)&driver_tstamp);
259 runtime->driver_tstamp = driver_tstamp;
262 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
263 unsigned int in_interrupt)
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;
275 old_hw_ptr = runtime->status->hw_ptr;
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
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,
290 &runtime->audio_tstamp_config,
291 &runtime->audio_tstamp_report);
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);
297 snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
300 if (pos == SNDRV_PCM_POS_XRUN) {
301 __snd_pcm_xrun(substream);
304 if (pos >= runtime->buffer_size) {
305 if (printk_ratelimit()) {
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);
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;
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) {
332 new_hw_ptr = hw_base + pos;
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) {
345 new_hw_ptr = hw_base + pos;
348 delta = new_hw_ptr - old_hw_ptr;
350 delta += runtime->boundary;
352 if (runtime->no_period_wakeup) {
353 snd_pcm_sframes_t xrun_threshold;
355 * Without regular period interrupts, we have to check
356 * the elapsed time to detect xruns.
358 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
359 if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
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) {
370 new_hw_ptr = hw_base + pos;
371 hdelta -= runtime->hw_ptr_buffer_jiffies;
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);
385 /* Do jiffies check only in xrun_debug mode */
386 if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
387 goto no_jiffies_check;
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.
393 if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
394 goto no_jiffies_check;
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) {
402 (((runtime->period_size * HZ) / runtime->rate)
404 /* move new_hw_ptr according jiffies not pos variable */
405 new_hw_ptr = old_hw_ptr;
407 /* use loop to avoid checks for delta overflows */
408 /* the delta value is small or zero in most cases */
410 new_hw_ptr += runtime->period_size;
411 if (new_hw_ptr >= runtime->boundary) {
412 new_hw_ptr -= runtime->boundary;
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 */
427 hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
430 if (delta > runtime->period_size + runtime->period_size / 2) {
431 hw_ptr_error(substream, in_interrupt,
433 "(stream=%i, delta=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
434 substream->stream, (long)delta,
440 if (runtime->status->hw_ptr == new_hw_ptr) {
441 runtime->hw_ptr_jiffies = curr_jiffies;
442 update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
446 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
447 runtime->silence_size > 0)
448 snd_pcm_playback_silence(substream, new_hw_ptr);
451 delta = new_hw_ptr - runtime->hw_ptr_interrupt;
453 delta += runtime->boundary;
454 delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
455 runtime->hw_ptr_interrupt += delta;
456 if (runtime->hw_ptr_interrupt >= runtime->boundary)
457 runtime->hw_ptr_interrupt -= runtime->boundary;
459 runtime->hw_ptr_base = hw_base;
460 runtime->status->hw_ptr = new_hw_ptr;
461 runtime->hw_ptr_jiffies = curr_jiffies;
462 if (crossed_boundary) {
463 snd_BUG_ON(crossed_boundary != 1);
464 runtime->hw_ptr_wrap += runtime->boundary;
467 update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
469 return snd_pcm_update_state(substream, runtime);
472 /* CAUTION: call it with irq disabled */
473 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
475 return snd_pcm_update_hw_ptr0(substream, 0);
479 * snd_pcm_set_ops - set the PCM operators
480 * @pcm: the pcm instance
481 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
482 * @ops: the operator table
484 * Sets the given PCM operators to the pcm instance.
486 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
487 const struct snd_pcm_ops *ops)
489 struct snd_pcm_str *stream = &pcm->streams[direction];
490 struct snd_pcm_substream *substream;
492 for (substream = stream->substream; substream != NULL; substream = substream->next)
493 substream->ops = ops;
495 EXPORT_SYMBOL(snd_pcm_set_ops);
498 * snd_pcm_sync - set the PCM sync id
499 * @substream: the pcm substream
501 * Sets the PCM sync identifier for the card.
503 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
505 struct snd_pcm_runtime *runtime = substream->runtime;
507 runtime->sync.id32[0] = substream->pcm->card->number;
508 runtime->sync.id32[1] = -1;
509 runtime->sync.id32[2] = -1;
510 runtime->sync.id32[3] = -1;
512 EXPORT_SYMBOL(snd_pcm_set_sync);
515 * Standard ioctl routine
518 static inline unsigned int div32(unsigned int a, unsigned int b,
529 static inline unsigned int div_down(unsigned int a, unsigned int b)
536 static inline unsigned int div_up(unsigned int a, unsigned int b)
548 static inline unsigned int mul(unsigned int a, unsigned int b)
552 if (div_down(UINT_MAX, a) < b)
557 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
558 unsigned int c, unsigned int *r)
560 u_int64_t n = (u_int64_t) a * b;
565 n = div_u64_rem(n, c, r);
574 * snd_interval_refine - refine the interval value of configurator
575 * @i: the interval value to refine
576 * @v: the interval value to refer to
578 * Refines the interval value with the reference value.
579 * The interval is changed to the range satisfying both intervals.
580 * The interval status (min, max, integer, etc.) are evaluated.
582 * Return: Positive if the value is changed, zero if it's not changed, or a
583 * negative error code.
585 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
588 if (snd_BUG_ON(snd_interval_empty(i)))
590 if (i->min < v->min) {
592 i->openmin = v->openmin;
594 } else if (i->min == v->min && !i->openmin && v->openmin) {
598 if (i->max > v->max) {
600 i->openmax = v->openmax;
602 } else if (i->max == v->max && !i->openmax && v->openmax) {
606 if (!i->integer && v->integer) {
619 } else if (!i->openmin && !i->openmax && i->min == i->max)
621 if (snd_interval_checkempty(i)) {
622 snd_interval_none(i);
627 EXPORT_SYMBOL(snd_interval_refine);
629 static int snd_interval_refine_first(struct snd_interval *i)
631 const unsigned int last_max = i->max;
633 if (snd_BUG_ON(snd_interval_empty(i)))
635 if (snd_interval_single(i))
640 /* only exclude max value if also excluded before refine */
641 i->openmax = (i->openmax && i->max >= last_max);
645 static int snd_interval_refine_last(struct snd_interval *i)
647 const unsigned int last_min = i->min;
649 if (snd_BUG_ON(snd_interval_empty(i)))
651 if (snd_interval_single(i))
656 /* only exclude min value if also excluded before refine */
657 i->openmin = (i->openmin && i->min <= last_min);
661 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
663 if (a->empty || b->empty) {
664 snd_interval_none(c);
668 c->min = mul(a->min, b->min);
669 c->openmin = (a->openmin || b->openmin);
670 c->max = mul(a->max, b->max);
671 c->openmax = (a->openmax || b->openmax);
672 c->integer = (a->integer && b->integer);
676 * snd_interval_div - refine the interval value with division
683 * Returns non-zero if the value is changed, zero if not changed.
685 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
688 if (a->empty || b->empty) {
689 snd_interval_none(c);
693 c->min = div32(a->min, b->max, &r);
694 c->openmin = (r || a->openmin || b->openmax);
696 c->max = div32(a->max, b->min, &r);
701 c->openmax = (a->openmax || b->openmin);
710 * snd_interval_muldivk - refine the interval value
713 * @k: divisor (as integer)
718 * Returns non-zero if the value is changed, zero if not changed.
720 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
721 unsigned int k, struct snd_interval *c)
724 if (a->empty || b->empty) {
725 snd_interval_none(c);
729 c->min = muldiv32(a->min, b->min, k, &r);
730 c->openmin = (r || a->openmin || b->openmin);
731 c->max = muldiv32(a->max, b->max, k, &r);
736 c->openmax = (a->openmax || b->openmax);
741 * snd_interval_mulkdiv - refine the interval value
743 * @k: dividend 2 (as integer)
749 * Returns non-zero if the value is changed, zero if not changed.
751 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
752 const struct snd_interval *b, struct snd_interval *c)
755 if (a->empty || b->empty) {
756 snd_interval_none(c);
760 c->min = muldiv32(a->min, k, b->max, &r);
761 c->openmin = (r || a->openmin || b->openmax);
763 c->max = muldiv32(a->max, k, b->min, &r);
768 c->openmax = (a->openmax || b->openmin);
780 * snd_interval_ratnum - refine the interval value
781 * @i: interval to refine
782 * @rats_count: number of ratnum_t
783 * @rats: ratnum_t array
784 * @nump: pointer to store the resultant numerator
785 * @denp: pointer to store the resultant denominator
787 * Return: Positive if the value is changed, zero if it's not changed, or a
788 * negative error code.
790 int snd_interval_ratnum(struct snd_interval *i,
791 unsigned int rats_count, const struct snd_ratnum *rats,
792 unsigned int *nump, unsigned int *denp)
794 unsigned int best_num, best_den;
797 struct snd_interval t;
799 unsigned int result_num, result_den;
802 best_num = best_den = best_diff = 0;
803 for (k = 0; k < rats_count; ++k) {
804 unsigned int num = rats[k].num;
806 unsigned int q = i->min;
810 den = div_up(num, q);
811 if (den < rats[k].den_min)
813 if (den > rats[k].den_max)
814 den = rats[k].den_max;
817 r = (den - rats[k].den_min) % rats[k].den_step;
821 diff = num - q * den;
825 diff * best_den < best_diff * den) {
835 t.min = div_down(best_num, best_den);
836 t.openmin = !!(best_num % best_den);
838 result_num = best_num;
839 result_diff = best_diff;
840 result_den = best_den;
841 best_num = best_den = best_diff = 0;
842 for (k = 0; k < rats_count; ++k) {
843 unsigned int num = rats[k].num;
845 unsigned int q = i->max;
851 den = div_down(num, q);
852 if (den > rats[k].den_max)
854 if (den < rats[k].den_min)
855 den = rats[k].den_min;
858 r = (den - rats[k].den_min) % rats[k].den_step;
860 den += rats[k].den_step - r;
862 diff = q * den - num;
866 diff * best_den < best_diff * den) {
876 t.max = div_up(best_num, best_den);
877 t.openmax = !!(best_num % best_den);
879 err = snd_interval_refine(i, &t);
883 if (snd_interval_single(i)) {
884 if (best_diff * result_den < result_diff * best_den) {
885 result_num = best_num;
886 result_den = best_den;
895 EXPORT_SYMBOL(snd_interval_ratnum);
898 * snd_interval_ratden - refine the interval value
899 * @i: interval to refine
900 * @rats_count: number of struct ratden
901 * @rats: struct ratden array
902 * @nump: pointer to store the resultant numerator
903 * @denp: pointer to store the resultant denominator
905 * Return: Positive if the value is changed, zero if it's not changed, or a
906 * negative error code.
908 static int snd_interval_ratden(struct snd_interval *i,
909 unsigned int rats_count,
910 const struct snd_ratden *rats,
911 unsigned int *nump, unsigned int *denp)
913 unsigned int best_num, best_diff, best_den;
915 struct snd_interval t;
918 best_num = best_den = best_diff = 0;
919 for (k = 0; k < rats_count; ++k) {
921 unsigned int den = rats[k].den;
922 unsigned int q = i->min;
925 if (num > rats[k].num_max)
927 if (num < rats[k].num_min)
928 num = rats[k].num_max;
931 r = (num - rats[k].num_min) % rats[k].num_step;
933 num += rats[k].num_step - r;
935 diff = num - q * den;
937 diff * best_den < best_diff * den) {
947 t.min = div_down(best_num, best_den);
948 t.openmin = !!(best_num % best_den);
950 best_num = best_den = best_diff = 0;
951 for (k = 0; k < rats_count; ++k) {
953 unsigned int den = rats[k].den;
954 unsigned int q = i->max;
957 if (num < rats[k].num_min)
959 if (num > rats[k].num_max)
960 num = rats[k].num_max;
963 r = (num - rats[k].num_min) % rats[k].num_step;
967 diff = q * den - num;
969 diff * best_den < best_diff * den) {
979 t.max = div_up(best_num, best_den);
980 t.openmax = !!(best_num % best_den);
982 err = snd_interval_refine(i, &t);
986 if (snd_interval_single(i)) {
996 * snd_interval_list - refine the interval value from the list
997 * @i: the interval value to refine
998 * @count: the number of elements in the list
999 * @list: the value list
1000 * @mask: the bit-mask to evaluate
1002 * Refines the interval value from the list.
1003 * When mask is non-zero, only the elements corresponding to bit 1 are
1006 * Return: Positive if the value is changed, zero if it's not changed, or a
1007 * negative error code.
1009 int snd_interval_list(struct snd_interval *i, unsigned int count,
1010 const unsigned int *list, unsigned int mask)
1013 struct snd_interval list_range;
1019 snd_interval_any(&list_range);
1020 list_range.min = UINT_MAX;
1022 for (k = 0; k < count; k++) {
1023 if (mask && !(mask & (1 << k)))
1025 if (!snd_interval_test(i, list[k]))
1027 list_range.min = min(list_range.min, list[k]);
1028 list_range.max = max(list_range.max, list[k]);
1030 return snd_interval_refine(i, &list_range);
1032 EXPORT_SYMBOL(snd_interval_list);
1035 * snd_interval_ranges - refine the interval value from the list of ranges
1036 * @i: the interval value to refine
1037 * @count: the number of elements in the list of ranges
1038 * @ranges: the ranges list
1039 * @mask: the bit-mask to evaluate
1041 * Refines the interval value from the list of ranges.
1042 * When mask is non-zero, only the elements corresponding to bit 1 are
1045 * Return: Positive if the value is changed, zero if it's not changed, or a
1046 * negative error code.
1048 int snd_interval_ranges(struct snd_interval *i, unsigned int count,
1049 const struct snd_interval *ranges, unsigned int mask)
1052 struct snd_interval range_union;
1053 struct snd_interval range;
1056 snd_interval_none(i);
1059 snd_interval_any(&range_union);
1060 range_union.min = UINT_MAX;
1061 range_union.max = 0;
1062 for (k = 0; k < count; k++) {
1063 if (mask && !(mask & (1 << k)))
1065 snd_interval_copy(&range, &ranges[k]);
1066 if (snd_interval_refine(&range, i) < 0)
1068 if (snd_interval_empty(&range))
1071 if (range.min < range_union.min) {
1072 range_union.min = range.min;
1073 range_union.openmin = 1;
1075 if (range.min == range_union.min && !range.openmin)
1076 range_union.openmin = 0;
1077 if (range.max > range_union.max) {
1078 range_union.max = range.max;
1079 range_union.openmax = 1;
1081 if (range.max == range_union.max && !range.openmax)
1082 range_union.openmax = 0;
1084 return snd_interval_refine(i, &range_union);
1086 EXPORT_SYMBOL(snd_interval_ranges);
1088 static int snd_interval_step(struct snd_interval *i, unsigned int step)
1093 if (n != 0 || i->openmin) {
1099 if (n != 0 || i->openmax) {
1104 if (snd_interval_checkempty(i)) {
1111 /* Info constraints helpers */
1114 * snd_pcm_hw_rule_add - add the hw-constraint rule
1115 * @runtime: the pcm runtime instance
1116 * @cond: condition bits
1117 * @var: the variable to evaluate
1118 * @func: the evaluation function
1119 * @private: the private data pointer passed to function
1120 * @dep: the dependent variables
1122 * Return: Zero if successful, or a negative error code on failure.
1124 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1126 snd_pcm_hw_rule_func_t func, void *private,
1129 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1130 struct snd_pcm_hw_rule *c;
1133 va_start(args, dep);
1134 if (constrs->rules_num >= constrs->rules_all) {
1135 struct snd_pcm_hw_rule *new;
1136 unsigned int new_rules = constrs->rules_all + 16;
1137 new = krealloc(constrs->rules, new_rules * sizeof(*c),
1143 constrs->rules = new;
1144 constrs->rules_all = new_rules;
1146 c = &constrs->rules[constrs->rules_num];
1150 c->private = private;
1153 if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1160 dep = va_arg(args, int);
1162 constrs->rules_num++;
1166 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1169 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1170 * @runtime: PCM runtime instance
1171 * @var: hw_params variable to apply the mask
1172 * @mask: the bitmap mask
1174 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1176 * Return: Zero if successful, or a negative error code on failure.
1178 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1181 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1182 struct snd_mask *maskp = constrs_mask(constrs, var);
1183 *maskp->bits &= mask;
1184 memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1185 if (*maskp->bits == 0)
1191 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1192 * @runtime: PCM runtime instance
1193 * @var: hw_params variable to apply the mask
1194 * @mask: the 64bit bitmap mask
1196 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1198 * Return: Zero if successful, or a negative error code on failure.
1200 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1203 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1204 struct snd_mask *maskp = constrs_mask(constrs, var);
1205 maskp->bits[0] &= (u_int32_t)mask;
1206 maskp->bits[1] &= (u_int32_t)(mask >> 32);
1207 memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1208 if (! maskp->bits[0] && ! maskp->bits[1])
1212 EXPORT_SYMBOL(snd_pcm_hw_constraint_mask64);
1215 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1216 * @runtime: PCM runtime instance
1217 * @var: hw_params variable to apply the integer constraint
1219 * Apply the constraint of integer to an interval parameter.
1221 * Return: Positive if the value is changed, zero if it's not changed, or a
1222 * negative error code.
1224 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1226 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1227 return snd_interval_setinteger(constrs_interval(constrs, var));
1229 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1232 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1233 * @runtime: PCM runtime instance
1234 * @var: hw_params variable to apply the range
1235 * @min: the minimal value
1236 * @max: the maximal value
1238 * Apply the min/max range constraint to an interval parameter.
1240 * Return: Positive if the value is changed, zero if it's not changed, or a
1241 * negative error code.
1243 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1244 unsigned int min, unsigned int max)
1246 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1247 struct snd_interval t;
1250 t.openmin = t.openmax = 0;
1252 return snd_interval_refine(constrs_interval(constrs, var), &t);
1254 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1256 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1257 struct snd_pcm_hw_rule *rule)
1259 struct snd_pcm_hw_constraint_list *list = rule->private;
1260 return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1265 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1266 * @runtime: PCM runtime instance
1267 * @cond: condition bits
1268 * @var: hw_params variable to apply the list constraint
1271 * Apply the list of constraints to an interval parameter.
1273 * Return: Zero if successful, or a negative error code on failure.
1275 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1277 snd_pcm_hw_param_t var,
1278 const struct snd_pcm_hw_constraint_list *l)
1280 return snd_pcm_hw_rule_add(runtime, cond, var,
1281 snd_pcm_hw_rule_list, (void *)l,
1284 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1286 static int snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params *params,
1287 struct snd_pcm_hw_rule *rule)
1289 struct snd_pcm_hw_constraint_ranges *r = rule->private;
1290 return snd_interval_ranges(hw_param_interval(params, rule->var),
1291 r->count, r->ranges, r->mask);
1296 * snd_pcm_hw_constraint_ranges - apply list of range constraints to a parameter
1297 * @runtime: PCM runtime instance
1298 * @cond: condition bits
1299 * @var: hw_params variable to apply the list of range constraints
1302 * Apply the list of range constraints to an interval parameter.
1304 * Return: Zero if successful, or a negative error code on failure.
1306 int snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime *runtime,
1308 snd_pcm_hw_param_t var,
1309 const struct snd_pcm_hw_constraint_ranges *r)
1311 return snd_pcm_hw_rule_add(runtime, cond, var,
1312 snd_pcm_hw_rule_ranges, (void *)r,
1315 EXPORT_SYMBOL(snd_pcm_hw_constraint_ranges);
1317 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1318 struct snd_pcm_hw_rule *rule)
1320 const struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1321 unsigned int num = 0, den = 0;
1323 err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1324 r->nrats, r->rats, &num, &den);
1325 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1326 params->rate_num = num;
1327 params->rate_den = den;
1333 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1334 * @runtime: PCM runtime instance
1335 * @cond: condition bits
1336 * @var: hw_params variable to apply the ratnums constraint
1337 * @r: struct snd_ratnums constriants
1339 * Return: Zero if successful, or a negative error code on failure.
1341 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1343 snd_pcm_hw_param_t var,
1344 const struct snd_pcm_hw_constraint_ratnums *r)
1346 return snd_pcm_hw_rule_add(runtime, cond, var,
1347 snd_pcm_hw_rule_ratnums, (void *)r,
1350 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1352 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1353 struct snd_pcm_hw_rule *rule)
1355 const struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1356 unsigned int num = 0, den = 0;
1357 int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1358 r->nrats, r->rats, &num, &den);
1359 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1360 params->rate_num = num;
1361 params->rate_den = den;
1367 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1368 * @runtime: PCM runtime instance
1369 * @cond: condition bits
1370 * @var: hw_params variable to apply the ratdens constraint
1371 * @r: struct snd_ratdens constriants
1373 * Return: Zero if successful, or a negative error code on failure.
1375 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1377 snd_pcm_hw_param_t var,
1378 const struct snd_pcm_hw_constraint_ratdens *r)
1380 return snd_pcm_hw_rule_add(runtime, cond, var,
1381 snd_pcm_hw_rule_ratdens, (void *)r,
1384 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1386 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1387 struct snd_pcm_hw_rule *rule)
1389 unsigned int l = (unsigned long) rule->private;
1390 int width = l & 0xffff;
1391 unsigned int msbits = l >> 16;
1392 const struct snd_interval *i =
1393 hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1395 if (!snd_interval_single(i))
1398 if ((snd_interval_value(i) == width) ||
1399 (width == 0 && snd_interval_value(i) > msbits))
1400 params->msbits = min_not_zero(params->msbits, msbits);
1406 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1407 * @runtime: PCM runtime instance
1408 * @cond: condition bits
1409 * @width: sample bits width
1410 * @msbits: msbits width
1412 * This constraint will set the number of most significant bits (msbits) if a
1413 * sample format with the specified width has been select. If width is set to 0
1414 * the msbits will be set for any sample format with a width larger than the
1417 * Return: Zero if successful, or a negative error code on failure.
1419 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1422 unsigned int msbits)
1424 unsigned long l = (msbits << 16) | width;
1425 return snd_pcm_hw_rule_add(runtime, cond, -1,
1426 snd_pcm_hw_rule_msbits,
1428 SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1430 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1432 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1433 struct snd_pcm_hw_rule *rule)
1435 unsigned long step = (unsigned long) rule->private;
1436 return snd_interval_step(hw_param_interval(params, rule->var), step);
1440 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1441 * @runtime: PCM runtime instance
1442 * @cond: condition bits
1443 * @var: hw_params variable to apply the step constraint
1446 * Return: Zero if successful, or a negative error code on failure.
1448 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1450 snd_pcm_hw_param_t var,
1453 return snd_pcm_hw_rule_add(runtime, cond, var,
1454 snd_pcm_hw_rule_step, (void *) step,
1457 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1459 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1461 static unsigned int pow2_sizes[] = {
1462 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1463 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1464 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1465 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1467 return snd_interval_list(hw_param_interval(params, rule->var),
1468 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1472 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1473 * @runtime: PCM runtime instance
1474 * @cond: condition bits
1475 * @var: hw_params variable to apply the power-of-2 constraint
1477 * Return: Zero if successful, or a negative error code on failure.
1479 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1481 snd_pcm_hw_param_t var)
1483 return snd_pcm_hw_rule_add(runtime, cond, var,
1484 snd_pcm_hw_rule_pow2, NULL,
1487 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1489 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1490 struct snd_pcm_hw_rule *rule)
1492 unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1493 struct snd_interval *rate;
1495 rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1496 return snd_interval_list(rate, 1, &base_rate, 0);
1500 * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1501 * @runtime: PCM runtime instance
1502 * @base_rate: the rate at which the hardware does not resample
1504 * Return: Zero if successful, or a negative error code on failure.
1506 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1507 unsigned int base_rate)
1509 return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1510 SNDRV_PCM_HW_PARAM_RATE,
1511 snd_pcm_hw_rule_noresample_func,
1512 (void *)(uintptr_t)base_rate,
1513 SNDRV_PCM_HW_PARAM_RATE, -1);
1515 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1517 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1518 snd_pcm_hw_param_t var)
1520 if (hw_is_mask(var)) {
1521 snd_mask_any(hw_param_mask(params, var));
1522 params->cmask |= 1 << var;
1523 params->rmask |= 1 << var;
1526 if (hw_is_interval(var)) {
1527 snd_interval_any(hw_param_interval(params, var));
1528 params->cmask |= 1 << var;
1529 params->rmask |= 1 << var;
1535 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1538 memset(params, 0, sizeof(*params));
1539 for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1540 _snd_pcm_hw_param_any(params, k);
1541 for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1542 _snd_pcm_hw_param_any(params, k);
1545 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1548 * snd_pcm_hw_param_value - return @params field @var value
1549 * @params: the hw_params instance
1550 * @var: parameter to retrieve
1551 * @dir: pointer to the direction (-1,0,1) or %NULL
1553 * Return: The value for field @var if it's fixed in configuration space
1554 * defined by @params. -%EINVAL otherwise.
1556 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1557 snd_pcm_hw_param_t var, int *dir)
1559 if (hw_is_mask(var)) {
1560 const struct snd_mask *mask = hw_param_mask_c(params, var);
1561 if (!snd_mask_single(mask))
1565 return snd_mask_value(mask);
1567 if (hw_is_interval(var)) {
1568 const struct snd_interval *i = hw_param_interval_c(params, var);
1569 if (!snd_interval_single(i))
1573 return snd_interval_value(i);
1577 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1579 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1580 snd_pcm_hw_param_t var)
1582 if (hw_is_mask(var)) {
1583 snd_mask_none(hw_param_mask(params, var));
1584 params->cmask |= 1 << var;
1585 params->rmask |= 1 << var;
1586 } else if (hw_is_interval(var)) {
1587 snd_interval_none(hw_param_interval(params, var));
1588 params->cmask |= 1 << var;
1589 params->rmask |= 1 << var;
1594 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1596 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1597 snd_pcm_hw_param_t var)
1600 if (hw_is_mask(var))
1601 changed = snd_mask_refine_first(hw_param_mask(params, var));
1602 else if (hw_is_interval(var))
1603 changed = snd_interval_refine_first(hw_param_interval(params, var));
1607 params->cmask |= 1 << var;
1608 params->rmask |= 1 << var;
1615 * snd_pcm_hw_param_first - refine config space and return minimum value
1616 * @pcm: PCM instance
1617 * @params: the hw_params instance
1618 * @var: parameter to retrieve
1619 * @dir: pointer to the direction (-1,0,1) or %NULL
1621 * Inside configuration space defined by @params remove from @var all
1622 * values > minimum. Reduce configuration space accordingly.
1624 * Return: The minimum, or a negative error code on failure.
1626 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1627 struct snd_pcm_hw_params *params,
1628 snd_pcm_hw_param_t var, int *dir)
1630 int changed = _snd_pcm_hw_param_first(params, var);
1633 if (params->rmask) {
1634 int err = snd_pcm_hw_refine(pcm, params);
1638 return snd_pcm_hw_param_value(params, var, dir);
1640 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1642 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1643 snd_pcm_hw_param_t var)
1646 if (hw_is_mask(var))
1647 changed = snd_mask_refine_last(hw_param_mask(params, var));
1648 else if (hw_is_interval(var))
1649 changed = snd_interval_refine_last(hw_param_interval(params, var));
1653 params->cmask |= 1 << var;
1654 params->rmask |= 1 << var;
1661 * snd_pcm_hw_param_last - refine config space and return maximum value
1662 * @pcm: PCM instance
1663 * @params: the hw_params instance
1664 * @var: parameter to retrieve
1665 * @dir: pointer to the direction (-1,0,1) or %NULL
1667 * Inside configuration space defined by @params remove from @var all
1668 * values < maximum. Reduce configuration space accordingly.
1670 * Return: The maximum, or a negative error code on failure.
1672 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1673 struct snd_pcm_hw_params *params,
1674 snd_pcm_hw_param_t var, int *dir)
1676 int changed = _snd_pcm_hw_param_last(params, var);
1679 if (params->rmask) {
1680 int err = snd_pcm_hw_refine(pcm, params);
1684 return snd_pcm_hw_param_value(params, var, dir);
1686 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1688 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1691 struct snd_pcm_runtime *runtime = substream->runtime;
1692 unsigned long flags;
1693 snd_pcm_stream_lock_irqsave(substream, flags);
1694 if (snd_pcm_running(substream) &&
1695 snd_pcm_update_hw_ptr(substream) >= 0)
1696 runtime->status->hw_ptr %= runtime->buffer_size;
1698 runtime->status->hw_ptr = 0;
1699 runtime->hw_ptr_wrap = 0;
1701 snd_pcm_stream_unlock_irqrestore(substream, flags);
1705 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1708 struct snd_pcm_channel_info *info = arg;
1709 struct snd_pcm_runtime *runtime = substream->runtime;
1711 if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1715 width = snd_pcm_format_physical_width(runtime->format);
1719 switch (runtime->access) {
1720 case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1721 case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1722 info->first = info->channel * width;
1723 info->step = runtime->channels * width;
1725 case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1726 case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1728 size_t size = runtime->dma_bytes / runtime->channels;
1729 info->first = info->channel * size * 8;
1740 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1743 struct snd_pcm_hw_params *params = arg;
1744 snd_pcm_format_t format;
1748 params->fifo_size = substream->runtime->hw.fifo_size;
1749 if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1750 format = params_format(params);
1751 channels = params_channels(params);
1752 frame_size = snd_pcm_format_size(format, channels);
1754 params->fifo_size /= frame_size;
1760 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1761 * @substream: the pcm substream instance
1762 * @cmd: ioctl command
1763 * @arg: ioctl argument
1765 * Processes the generic ioctl commands for PCM.
1766 * Can be passed as the ioctl callback for PCM ops.
1768 * Return: Zero if successful, or a negative error code on failure.
1770 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1771 unsigned int cmd, void *arg)
1774 case SNDRV_PCM_IOCTL1_RESET:
1775 return snd_pcm_lib_ioctl_reset(substream, arg);
1776 case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1777 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1778 case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1779 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1783 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1786 * snd_pcm_period_elapsed - update the pcm status for the next period
1787 * @substream: the pcm substream instance
1789 * This function is called from the interrupt handler when the
1790 * PCM has processed the period size. It will update the current
1791 * pointer, wake up sleepers, etc.
1793 * Even if more than one periods have elapsed since the last call, you
1794 * have to call this only once.
1796 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1798 struct snd_pcm_runtime *runtime;
1799 unsigned long flags;
1801 if (snd_BUG_ON(!substream))
1804 snd_pcm_stream_lock_irqsave(substream, flags);
1805 if (PCM_RUNTIME_CHECK(substream))
1807 runtime = substream->runtime;
1809 if (!snd_pcm_running(substream) ||
1810 snd_pcm_update_hw_ptr0(substream, 1) < 0)
1813 #ifdef CONFIG_SND_PCM_TIMER
1814 if (substream->timer_running)
1815 snd_timer_interrupt(substream->timer, 1);
1818 kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1820 snd_pcm_stream_unlock_irqrestore(substream, flags);
1822 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1825 * Wait until avail_min data becomes available
1826 * Returns a negative error code if any error occurs during operation.
1827 * The available space is stored on availp. When err = 0 and avail = 0
1828 * on the capture stream, it indicates the stream is in DRAINING state.
1830 static int wait_for_avail(struct snd_pcm_substream *substream,
1831 snd_pcm_uframes_t *availp)
1833 struct snd_pcm_runtime *runtime = substream->runtime;
1834 int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1835 wait_queue_entry_t wait;
1837 snd_pcm_uframes_t avail = 0;
1838 long wait_time, tout;
1840 init_waitqueue_entry(&wait, current);
1841 set_current_state(TASK_INTERRUPTIBLE);
1842 add_wait_queue(&runtime->tsleep, &wait);
1844 if (runtime->no_period_wakeup)
1845 wait_time = MAX_SCHEDULE_TIMEOUT;
1847 /* use wait time from substream if available */
1848 if (substream->wait_time) {
1849 wait_time = substream->wait_time;
1853 if (runtime->rate) {
1854 long t = runtime->period_size * 2 /
1856 wait_time = max(t, wait_time);
1858 wait_time = msecs_to_jiffies(wait_time * 1000);
1863 if (signal_pending(current)) {
1869 * We need to check if space became available already
1870 * (and thus the wakeup happened already) first to close
1871 * the race of space already having become available.
1872 * This check must happen after been added to the waitqueue
1873 * and having current state be INTERRUPTIBLE.
1875 avail = snd_pcm_avail(substream);
1876 if (avail >= runtime->twake)
1878 snd_pcm_stream_unlock_irq(substream);
1880 tout = schedule_timeout(wait_time);
1882 snd_pcm_stream_lock_irq(substream);
1883 set_current_state(TASK_INTERRUPTIBLE);
1884 switch (runtime->status->state) {
1885 case SNDRV_PCM_STATE_SUSPENDED:
1888 case SNDRV_PCM_STATE_XRUN:
1891 case SNDRV_PCM_STATE_DRAINING:
1895 avail = 0; /* indicate draining */
1897 case SNDRV_PCM_STATE_OPEN:
1898 case SNDRV_PCM_STATE_SETUP:
1899 case SNDRV_PCM_STATE_DISCONNECTED:
1902 case SNDRV_PCM_STATE_PAUSED:
1906 pcm_dbg(substream->pcm,
1907 "%s write error (DMA or IRQ trouble?)\n",
1908 is_playback ? "playback" : "capture");
1914 set_current_state(TASK_RUNNING);
1915 remove_wait_queue(&runtime->tsleep, &wait);
1920 typedef int (*pcm_transfer_f)(struct snd_pcm_substream *substream,
1921 int channel, unsigned long hwoff,
1922 void *buf, unsigned long bytes);
1924 typedef int (*pcm_copy_f)(struct snd_pcm_substream *, snd_pcm_uframes_t, void *,
1925 snd_pcm_uframes_t, snd_pcm_uframes_t, pcm_transfer_f);
1927 /* calculate the target DMA-buffer position to be written/read */
1928 static void *get_dma_ptr(struct snd_pcm_runtime *runtime,
1929 int channel, unsigned long hwoff)
1931 return runtime->dma_area + hwoff +
1932 channel * (runtime->dma_bytes / runtime->channels);
1935 /* default copy_user ops for write; used for both interleaved and non- modes */
1936 static int default_write_copy(struct snd_pcm_substream *substream,
1937 int channel, unsigned long hwoff,
1938 void *buf, unsigned long bytes)
1940 if (copy_from_user(get_dma_ptr(substream->runtime, channel, hwoff),
1941 (void __user *)buf, bytes))
1946 /* default copy_kernel ops for write */
1947 static int default_write_copy_kernel(struct snd_pcm_substream *substream,
1948 int channel, unsigned long hwoff,
1949 void *buf, unsigned long bytes)
1951 memcpy(get_dma_ptr(substream->runtime, channel, hwoff), buf, bytes);
1955 /* fill silence instead of copy data; called as a transfer helper
1956 * from __snd_pcm_lib_write() or directly from noninterleaved_copy() when
1957 * a NULL buffer is passed
1959 static int fill_silence(struct snd_pcm_substream *substream, int channel,
1960 unsigned long hwoff, void *buf, unsigned long bytes)
1962 struct snd_pcm_runtime *runtime = substream->runtime;
1964 if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
1966 if (substream->ops->fill_silence)
1967 return substream->ops->fill_silence(substream, channel,
1970 snd_pcm_format_set_silence(runtime->format,
1971 get_dma_ptr(runtime, channel, hwoff),
1972 bytes_to_samples(runtime, bytes));
1976 /* default copy_user ops for read; used for both interleaved and non- modes */
1977 static int default_read_copy(struct snd_pcm_substream *substream,
1978 int channel, unsigned long hwoff,
1979 void *buf, unsigned long bytes)
1981 if (copy_to_user((void __user *)buf,
1982 get_dma_ptr(substream->runtime, channel, hwoff),
1988 /* default copy_kernel ops for read */
1989 static int default_read_copy_kernel(struct snd_pcm_substream *substream,
1990 int channel, unsigned long hwoff,
1991 void *buf, unsigned long bytes)
1993 memcpy(buf, get_dma_ptr(substream->runtime, channel, hwoff), bytes);
1997 /* call transfer function with the converted pointers and sizes;
1998 * for interleaved mode, it's one shot for all samples
2000 static int interleaved_copy(struct snd_pcm_substream *substream,
2001 snd_pcm_uframes_t hwoff, void *data,
2002 snd_pcm_uframes_t off,
2003 snd_pcm_uframes_t frames,
2004 pcm_transfer_f transfer)
2006 struct snd_pcm_runtime *runtime = substream->runtime;
2008 /* convert to bytes */
2009 hwoff = frames_to_bytes(runtime, hwoff);
2010 off = frames_to_bytes(runtime, off);
2011 frames = frames_to_bytes(runtime, frames);
2012 return transfer(substream, 0, hwoff, data + off, frames);
2015 /* call transfer function with the converted pointers and sizes for each
2016 * non-interleaved channel; when buffer is NULL, silencing instead of copying
2018 static int noninterleaved_copy(struct snd_pcm_substream *substream,
2019 snd_pcm_uframes_t hwoff, void *data,
2020 snd_pcm_uframes_t off,
2021 snd_pcm_uframes_t frames,
2022 pcm_transfer_f transfer)
2024 struct snd_pcm_runtime *runtime = substream->runtime;
2025 int channels = runtime->channels;
2029 /* convert to bytes; note that it's not frames_to_bytes() here.
2030 * in non-interleaved mode, we copy for each channel, thus
2031 * each copy is n_samples bytes x channels = whole frames.
2033 off = samples_to_bytes(runtime, off);
2034 frames = samples_to_bytes(runtime, frames);
2035 hwoff = samples_to_bytes(runtime, hwoff);
2036 for (c = 0; c < channels; ++c, ++bufs) {
2037 if (!data || !*bufs)
2038 err = fill_silence(substream, c, hwoff, NULL, frames);
2040 err = transfer(substream, c, hwoff, *bufs + off,
2048 /* fill silence on the given buffer position;
2049 * called from snd_pcm_playback_silence()
2051 static int fill_silence_frames(struct snd_pcm_substream *substream,
2052 snd_pcm_uframes_t off, snd_pcm_uframes_t frames)
2054 if (substream->runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
2055 substream->runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED)
2056 return interleaved_copy(substream, off, NULL, 0, frames,
2059 return noninterleaved_copy(substream, off, NULL, 0, frames,
2063 /* sanity-check for read/write methods */
2064 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2066 struct snd_pcm_runtime *runtime;
2067 if (PCM_RUNTIME_CHECK(substream))
2069 runtime = substream->runtime;
2070 if (snd_BUG_ON(!substream->ops->copy_user && !runtime->dma_area))
2072 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2077 static int pcm_accessible_state(struct snd_pcm_runtime *runtime)
2079 switch (runtime->status->state) {
2080 case SNDRV_PCM_STATE_PREPARED:
2081 case SNDRV_PCM_STATE_RUNNING:
2082 case SNDRV_PCM_STATE_PAUSED:
2084 case SNDRV_PCM_STATE_XRUN:
2086 case SNDRV_PCM_STATE_SUSPENDED:
2093 /* update to the given appl_ptr and call ack callback if needed;
2094 * when an error is returned, take back to the original value
2096 int pcm_lib_apply_appl_ptr(struct snd_pcm_substream *substream,
2097 snd_pcm_uframes_t appl_ptr)
2099 struct snd_pcm_runtime *runtime = substream->runtime;
2100 snd_pcm_uframes_t old_appl_ptr = runtime->control->appl_ptr;
2103 if (old_appl_ptr == appl_ptr)
2106 runtime->control->appl_ptr = appl_ptr;
2107 if (substream->ops->ack) {
2108 ret = substream->ops->ack(substream);
2110 runtime->control->appl_ptr = old_appl_ptr;
2115 trace_applptr(substream, old_appl_ptr, appl_ptr);
2120 /* the common loop for read/write data */
2121 snd_pcm_sframes_t __snd_pcm_lib_xfer(struct snd_pcm_substream *substream,
2122 void *data, bool interleaved,
2123 snd_pcm_uframes_t size, bool in_kernel)
2125 struct snd_pcm_runtime *runtime = substream->runtime;
2126 snd_pcm_uframes_t xfer = 0;
2127 snd_pcm_uframes_t offset = 0;
2128 snd_pcm_uframes_t avail;
2130 pcm_transfer_f transfer;
2135 err = pcm_sanity_check(substream);
2139 is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
2141 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2142 runtime->channels > 1)
2144 writer = interleaved_copy;
2146 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2148 writer = noninterleaved_copy;
2153 transfer = fill_silence;
2156 } else if (in_kernel) {
2157 if (substream->ops->copy_kernel)
2158 transfer = substream->ops->copy_kernel;
2160 transfer = is_playback ?
2161 default_write_copy_kernel : default_read_copy_kernel;
2163 if (substream->ops->copy_user)
2164 transfer = (pcm_transfer_f)substream->ops->copy_user;
2166 transfer = is_playback ?
2167 default_write_copy : default_read_copy;
2173 nonblock = !!(substream->f_flags & O_NONBLOCK);
2175 snd_pcm_stream_lock_irq(substream);
2176 err = pcm_accessible_state(runtime);
2181 runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2182 size >= runtime->start_threshold) {
2183 err = snd_pcm_start(substream);
2188 runtime->twake = runtime->control->avail_min ? : 1;
2189 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2190 snd_pcm_update_hw_ptr(substream);
2191 avail = snd_pcm_avail(substream);
2193 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2194 snd_pcm_uframes_t cont;
2197 runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
2198 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2205 runtime->twake = min_t(snd_pcm_uframes_t, size,
2206 runtime->control->avail_min ? : 1);
2207 err = wait_for_avail(substream, &avail);
2211 continue; /* draining */
2213 frames = size > avail ? avail : size;
2214 appl_ptr = READ_ONCE(runtime->control->appl_ptr);
2215 appl_ofs = appl_ptr % runtime->buffer_size;
2216 cont = runtime->buffer_size - appl_ofs;
2219 if (snd_BUG_ON(!frames)) {
2221 snd_pcm_stream_unlock_irq(substream);
2224 snd_pcm_stream_unlock_irq(substream);
2225 err = writer(substream, appl_ofs, data, offset, frames,
2227 snd_pcm_stream_lock_irq(substream);
2230 err = pcm_accessible_state(runtime);
2234 if (appl_ptr >= runtime->boundary)
2235 appl_ptr -= runtime->boundary;
2236 err = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2245 runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2246 snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2247 err = snd_pcm_start(substream);
2254 if (xfer > 0 && err >= 0)
2255 snd_pcm_update_state(substream, runtime);
2256 snd_pcm_stream_unlock_irq(substream);
2257 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2259 EXPORT_SYMBOL(__snd_pcm_lib_xfer);
2262 * standard channel mapping helpers
2265 /* default channel maps for multi-channel playbacks, up to 8 channels */
2266 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2268 .map = { SNDRV_CHMAP_MONO } },
2270 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2272 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2273 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2275 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2276 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2277 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2279 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2280 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2281 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2282 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2285 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2287 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2288 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2290 .map = { SNDRV_CHMAP_MONO } },
2292 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2294 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2295 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2297 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2298 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2299 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2301 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2302 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2303 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2304 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2307 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2309 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2311 if (ch > info->max_channels)
2313 return !info->channel_mask || (info->channel_mask & (1U << ch));
2316 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2317 struct snd_ctl_elem_info *uinfo)
2319 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2321 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2323 uinfo->count = info->max_channels;
2324 uinfo->value.integer.min = 0;
2325 uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2329 /* get callback for channel map ctl element
2330 * stores the channel position firstly matching with the current channels
2332 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2333 struct snd_ctl_elem_value *ucontrol)
2335 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2336 unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2337 struct snd_pcm_substream *substream;
2338 const struct snd_pcm_chmap_elem *map;
2342 substream = snd_pcm_chmap_substream(info, idx);
2345 memset(ucontrol->value.integer.value, 0,
2346 sizeof(ucontrol->value.integer.value));
2347 if (!substream->runtime)
2348 return 0; /* no channels set */
2349 for (map = info->chmap; map->channels; map++) {
2351 if (map->channels == substream->runtime->channels &&
2352 valid_chmap_channels(info, map->channels)) {
2353 for (i = 0; i < map->channels; i++)
2354 ucontrol->value.integer.value[i] = map->map[i];
2361 /* tlv callback for channel map ctl element
2362 * expands the pre-defined channel maps in a form of TLV
2364 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2365 unsigned int size, unsigned int __user *tlv)
2367 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2368 const struct snd_pcm_chmap_elem *map;
2369 unsigned int __user *dst;
2376 if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2380 for (map = info->chmap; map->channels; map++) {
2381 int chs_bytes = map->channels * 4;
2382 if (!valid_chmap_channels(info, map->channels))
2386 if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2387 put_user(chs_bytes, dst + 1))
2392 if (size < chs_bytes)
2396 for (c = 0; c < map->channels; c++) {
2397 if (put_user(map->map[c], dst))
2402 if (put_user(count, tlv + 1))
2407 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2409 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2410 info->pcm->streams[info->stream].chmap_kctl = NULL;
2415 * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2416 * @pcm: the assigned PCM instance
2417 * @stream: stream direction
2418 * @chmap: channel map elements (for query)
2419 * @max_channels: the max number of channels for the stream
2420 * @private_value: the value passed to each kcontrol's private_value field
2421 * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2423 * Create channel-mapping control elements assigned to the given PCM stream(s).
2424 * Return: Zero if successful, or a negative error value.
2426 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2427 const struct snd_pcm_chmap_elem *chmap,
2429 unsigned long private_value,
2430 struct snd_pcm_chmap **info_ret)
2432 struct snd_pcm_chmap *info;
2433 struct snd_kcontrol_new knew = {
2434 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
2435 .access = SNDRV_CTL_ELEM_ACCESS_READ |
2436 SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2437 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2438 .info = pcm_chmap_ctl_info,
2439 .get = pcm_chmap_ctl_get,
2440 .tlv.c = pcm_chmap_ctl_tlv,
2444 if (WARN_ON(pcm->streams[stream].chmap_kctl))
2446 info = kzalloc(sizeof(*info), GFP_KERNEL);
2450 info->stream = stream;
2451 info->chmap = chmap;
2452 info->max_channels = max_channels;
2453 if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2454 knew.name = "Playback Channel Map";
2456 knew.name = "Capture Channel Map";
2457 knew.device = pcm->device;
2458 knew.count = pcm->streams[stream].substream_count;
2459 knew.private_value = private_value;
2460 info->kctl = snd_ctl_new1(&knew, info);
2465 info->kctl->private_free = pcm_chmap_ctl_private_free;
2466 err = snd_ctl_add(pcm->card, info->kctl);
2469 pcm->streams[stream].chmap_kctl = info->kctl;
2474 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);