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/time.h>
25 #include <linux/math64.h>
26 #include <linux/export.h>
27 #include <sound/core.h>
28 #include <sound/control.h>
29 #include <sound/tlv.h>
30 #include <sound/info.h>
31 #include <sound/pcm.h>
32 #include <sound/pcm_params.h>
33 #include <sound/timer.h>
36 * fill ring buffer with silence
37 * runtime->silence_start: starting pointer to silence area
38 * runtime->silence_filled: size filled with silence
39 * runtime->silence_threshold: threshold from application
40 * runtime->silence_size: maximal size from application
42 * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
44 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
46 struct snd_pcm_runtime *runtime = substream->runtime;
47 snd_pcm_uframes_t frames, ofs, transfer;
49 if (runtime->silence_size < runtime->boundary) {
50 snd_pcm_sframes_t noise_dist, n;
51 if (runtime->silence_start != runtime->control->appl_ptr) {
52 n = runtime->control->appl_ptr - runtime->silence_start;
54 n += runtime->boundary;
55 if ((snd_pcm_uframes_t)n < runtime->silence_filled)
56 runtime->silence_filled -= n;
58 runtime->silence_filled = 0;
59 runtime->silence_start = runtime->control->appl_ptr;
61 if (runtime->silence_filled >= runtime->buffer_size)
63 noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
64 if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
66 frames = runtime->silence_threshold - noise_dist;
67 if (frames > runtime->silence_size)
68 frames = runtime->silence_size;
70 if (new_hw_ptr == ULONG_MAX) { /* initialization */
71 snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
72 if (avail > runtime->buffer_size)
73 avail = runtime->buffer_size;
74 runtime->silence_filled = avail > 0 ? avail : 0;
75 runtime->silence_start = (runtime->status->hw_ptr +
76 runtime->silence_filled) %
79 ofs = runtime->status->hw_ptr;
80 frames = new_hw_ptr - ofs;
81 if ((snd_pcm_sframes_t)frames < 0)
82 frames += runtime->boundary;
83 runtime->silence_filled -= frames;
84 if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
85 runtime->silence_filled = 0;
86 runtime->silence_start = new_hw_ptr;
88 runtime->silence_start = ofs;
91 frames = runtime->buffer_size - runtime->silence_filled;
93 if (snd_BUG_ON(frames > runtime->buffer_size))
97 ofs = runtime->silence_start % runtime->buffer_size;
99 transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
100 if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
101 runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
102 if (substream->ops->silence) {
104 err = substream->ops->silence(substream, -1, ofs, transfer);
107 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
108 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
112 unsigned int channels = runtime->channels;
113 if (substream->ops->silence) {
114 for (c = 0; c < channels; ++c) {
116 err = substream->ops->silence(substream, c, ofs, transfer);
120 size_t dma_csize = runtime->dma_bytes / channels;
121 for (c = 0; c < channels; ++c) {
122 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
123 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
127 runtime->silence_filled += transfer;
133 #ifdef CONFIG_SND_DEBUG
134 void snd_pcm_debug_name(struct snd_pcm_substream *substream,
135 char *name, size_t len)
137 snprintf(name, len, "pcmC%dD%d%c:%d",
138 substream->pcm->card->number,
139 substream->pcm->device,
140 substream->stream ? 'c' : 'p',
143 EXPORT_SYMBOL(snd_pcm_debug_name);
146 #define XRUN_DEBUG_BASIC (1<<0)
147 #define XRUN_DEBUG_STACK (1<<1) /* dump also stack */
148 #define XRUN_DEBUG_JIFFIESCHECK (1<<2) /* do jiffies check */
149 #define XRUN_DEBUG_PERIODUPDATE (1<<3) /* full period update info */
150 #define XRUN_DEBUG_HWPTRUPDATE (1<<4) /* full hwptr update info */
151 #define XRUN_DEBUG_LOG (1<<5) /* show last 10 positions on err */
152 #define XRUN_DEBUG_LOGONCE (1<<6) /* do above only once */
154 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
156 #define xrun_debug(substream, mask) \
157 ((substream)->pstr->xrun_debug & (mask))
159 #define xrun_debug(substream, mask) 0
162 #define dump_stack_on_xrun(substream) do { \
163 if (xrun_debug(substream, XRUN_DEBUG_STACK)) \
167 static void xrun(struct snd_pcm_substream *substream)
169 struct snd_pcm_runtime *runtime = substream->runtime;
171 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
172 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
173 snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
174 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
176 snd_pcm_debug_name(substream, name, sizeof(name));
177 snd_printd(KERN_DEBUG "XRUN: %s\n", name);
178 dump_stack_on_xrun(substream);
182 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
183 #define hw_ptr_error(substream, fmt, args...) \
185 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) { \
186 xrun_log_show(substream); \
187 if (printk_ratelimit()) { \
188 snd_printd("PCM: " fmt, ##args); \
190 dump_stack_on_xrun(substream); \
194 #define XRUN_LOG_CNT 10
196 struct hwptr_log_entry {
197 unsigned int in_interrupt;
198 unsigned long jiffies;
199 snd_pcm_uframes_t pos;
200 snd_pcm_uframes_t period_size;
201 snd_pcm_uframes_t buffer_size;
202 snd_pcm_uframes_t old_hw_ptr;
203 snd_pcm_uframes_t hw_ptr_base;
206 struct snd_pcm_hwptr_log {
209 struct hwptr_log_entry entries[XRUN_LOG_CNT];
212 static void xrun_log(struct snd_pcm_substream *substream,
213 snd_pcm_uframes_t pos, int in_interrupt)
215 struct snd_pcm_runtime *runtime = substream->runtime;
216 struct snd_pcm_hwptr_log *log = runtime->hwptr_log;
217 struct hwptr_log_entry *entry;
220 log = kzalloc(sizeof(*log), GFP_ATOMIC);
223 runtime->hwptr_log = log;
225 if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
228 entry = &log->entries[log->idx];
229 entry->in_interrupt = in_interrupt;
230 entry->jiffies = jiffies;
232 entry->period_size = runtime->period_size;
233 entry->buffer_size = runtime->buffer_size;
234 entry->old_hw_ptr = runtime->status->hw_ptr;
235 entry->hw_ptr_base = runtime->hw_ptr_base;
236 log->idx = (log->idx + 1) % XRUN_LOG_CNT;
239 static void xrun_log_show(struct snd_pcm_substream *substream)
241 struct snd_pcm_hwptr_log *log = substream->runtime->hwptr_log;
242 struct hwptr_log_entry *entry;
249 if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
251 snd_pcm_debug_name(substream, name, sizeof(name));
252 for (cnt = 0, idx = log->idx; cnt < XRUN_LOG_CNT; cnt++) {
253 entry = &log->entries[idx];
254 if (entry->period_size == 0)
256 snd_printd("hwptr log: %s: %sj=%lu, pos=%ld/%ld/%ld, "
258 name, entry->in_interrupt ? "[Q] " : "",
260 (unsigned long)entry->pos,
261 (unsigned long)entry->period_size,
262 (unsigned long)entry->buffer_size,
263 (unsigned long)entry->old_hw_ptr,
264 (unsigned long)entry->hw_ptr_base);
271 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
273 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
274 #define xrun_log(substream, pos, in_interrupt) do { } while (0)
275 #define xrun_log_show(substream) do { } while (0)
279 int snd_pcm_update_state(struct snd_pcm_substream *substream,
280 struct snd_pcm_runtime *runtime)
282 snd_pcm_uframes_t avail;
284 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
285 avail = snd_pcm_playback_avail(runtime);
287 avail = snd_pcm_capture_avail(runtime);
288 if (avail > runtime->avail_max)
289 runtime->avail_max = avail;
290 if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
291 if (avail >= runtime->buffer_size) {
292 snd_pcm_drain_done(substream);
296 if (avail >= runtime->stop_threshold) {
301 if (runtime->twake) {
302 if (avail >= runtime->twake)
303 wake_up(&runtime->tsleep);
304 } else if (avail >= runtime->control->avail_min)
305 wake_up(&runtime->sleep);
309 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
310 unsigned int in_interrupt)
312 struct snd_pcm_runtime *runtime = substream->runtime;
313 snd_pcm_uframes_t pos;
314 snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
315 snd_pcm_sframes_t hdelta, delta;
316 unsigned long jdelta;
317 unsigned long curr_jiffies;
318 struct timespec curr_tstamp;
320 old_hw_ptr = runtime->status->hw_ptr;
323 * group pointer, time and jiffies reads to allow for more
324 * accurate correlations/corrections.
325 * The values are stored at the end of this routine after
326 * corrections for hw_ptr position
328 pos = substream->ops->pointer(substream);
329 curr_jiffies = jiffies;
330 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
331 snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
333 if (pos == SNDRV_PCM_POS_XRUN) {
337 if (pos >= runtime->buffer_size) {
338 if (printk_ratelimit()) {
340 snd_pcm_debug_name(substream, name, sizeof(name));
341 xrun_log_show(substream);
342 snd_printd(KERN_ERR "BUG: %s, pos = %ld, "
343 "buffer size = %ld, period size = %ld\n",
344 name, pos, runtime->buffer_size,
345 runtime->period_size);
349 pos -= pos % runtime->min_align;
350 if (xrun_debug(substream, XRUN_DEBUG_LOG))
351 xrun_log(substream, pos, in_interrupt);
352 hw_base = runtime->hw_ptr_base;
353 new_hw_ptr = hw_base + pos;
355 /* we know that one period was processed */
356 /* delta = "expected next hw_ptr" for in_interrupt != 0 */
357 delta = runtime->hw_ptr_interrupt + runtime->period_size;
358 if (delta > new_hw_ptr) {
359 /* check for double acknowledged interrupts */
360 hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
361 if (hdelta > runtime->hw_ptr_buffer_jiffies/2) {
362 hw_base += runtime->buffer_size;
363 if (hw_base >= runtime->boundary)
365 new_hw_ptr = hw_base + pos;
370 /* new_hw_ptr might be lower than old_hw_ptr in case when */
371 /* pointer crosses the end of the ring buffer */
372 if (new_hw_ptr < old_hw_ptr) {
373 hw_base += runtime->buffer_size;
374 if (hw_base >= runtime->boundary)
376 new_hw_ptr = hw_base + pos;
379 delta = new_hw_ptr - old_hw_ptr;
381 delta += runtime->boundary;
382 if (xrun_debug(substream, in_interrupt ?
383 XRUN_DEBUG_PERIODUPDATE : XRUN_DEBUG_HWPTRUPDATE)) {
385 snd_pcm_debug_name(substream, name, sizeof(name));
386 snd_printd("%s_update: %s: pos=%u/%u/%u, "
387 "hwptr=%ld/%ld/%ld/%ld\n",
388 in_interrupt ? "period" : "hwptr",
391 (unsigned int)runtime->period_size,
392 (unsigned int)runtime->buffer_size,
393 (unsigned long)delta,
394 (unsigned long)old_hw_ptr,
395 (unsigned long)new_hw_ptr,
396 (unsigned long)runtime->hw_ptr_base);
399 if (runtime->no_period_wakeup) {
400 snd_pcm_sframes_t xrun_threshold;
402 * Without regular period interrupts, we have to check
403 * the elapsed time to detect xruns.
405 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
406 if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
408 hdelta = jdelta - delta * HZ / runtime->rate;
409 xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
410 while (hdelta > xrun_threshold) {
411 delta += runtime->buffer_size;
412 hw_base += runtime->buffer_size;
413 if (hw_base >= runtime->boundary)
415 new_hw_ptr = hw_base + pos;
416 hdelta -= runtime->hw_ptr_buffer_jiffies;
421 /* something must be really wrong */
422 if (delta >= runtime->buffer_size + runtime->period_size) {
423 hw_ptr_error(substream,
424 "Unexpected hw_pointer value %s"
425 "(stream=%i, pos=%ld, new_hw_ptr=%ld, "
427 in_interrupt ? "[Q] " : "[P]",
428 substream->stream, (long)pos,
429 (long)new_hw_ptr, (long)old_hw_ptr);
433 /* Do jiffies check only in xrun_debug mode */
434 if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
435 goto no_jiffies_check;
437 /* Skip the jiffies check for hardwares with BATCH flag.
438 * Such hardware usually just increases the position at each IRQ,
439 * thus it can't give any strange position.
441 if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
442 goto no_jiffies_check;
444 if (hdelta < runtime->delay)
445 goto no_jiffies_check;
446 hdelta -= runtime->delay;
447 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
448 if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
450 (((runtime->period_size * HZ) / runtime->rate)
452 /* move new_hw_ptr according jiffies not pos variable */
453 new_hw_ptr = old_hw_ptr;
455 /* use loop to avoid checks for delta overflows */
456 /* the delta value is small or zero in most cases */
458 new_hw_ptr += runtime->period_size;
459 if (new_hw_ptr >= runtime->boundary)
460 new_hw_ptr -= runtime->boundary;
463 /* align hw_base to buffer_size */
464 hw_ptr_error(substream,
465 "hw_ptr skipping! %s"
466 "(pos=%ld, delta=%ld, period=%ld, "
467 "jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
468 in_interrupt ? "[Q] " : "",
469 (long)pos, (long)hdelta,
470 (long)runtime->period_size, jdelta,
471 ((hdelta * HZ) / runtime->rate), hw_base,
472 (unsigned long)old_hw_ptr,
473 (unsigned long)new_hw_ptr);
474 /* reset values to proper state */
476 hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
479 if (delta > runtime->period_size + runtime->period_size / 2) {
480 hw_ptr_error(substream,
481 "Lost interrupts? %s"
482 "(stream=%i, delta=%ld, new_hw_ptr=%ld, "
484 in_interrupt ? "[Q] " : "",
485 substream->stream, (long)delta,
491 if (runtime->status->hw_ptr == new_hw_ptr)
494 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
495 runtime->silence_size > 0)
496 snd_pcm_playback_silence(substream, new_hw_ptr);
499 delta = new_hw_ptr - runtime->hw_ptr_interrupt;
501 delta += runtime->boundary;
502 delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
503 runtime->hw_ptr_interrupt += delta;
504 if (runtime->hw_ptr_interrupt >= runtime->boundary)
505 runtime->hw_ptr_interrupt -= runtime->boundary;
507 runtime->hw_ptr_base = hw_base;
508 runtime->status->hw_ptr = new_hw_ptr;
509 runtime->hw_ptr_jiffies = curr_jiffies;
510 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
511 runtime->status->tstamp = curr_tstamp;
513 return snd_pcm_update_state(substream, runtime);
516 /* CAUTION: call it with irq disabled */
517 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
519 return snd_pcm_update_hw_ptr0(substream, 0);
523 * snd_pcm_set_ops - set the PCM operators
524 * @pcm: the pcm instance
525 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
526 * @ops: the operator table
528 * Sets the given PCM operators to the pcm instance.
530 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction, struct snd_pcm_ops *ops)
532 struct snd_pcm_str *stream = &pcm->streams[direction];
533 struct snd_pcm_substream *substream;
535 for (substream = stream->substream; substream != NULL; substream = substream->next)
536 substream->ops = ops;
539 EXPORT_SYMBOL(snd_pcm_set_ops);
542 * snd_pcm_sync - set the PCM sync id
543 * @substream: the pcm substream
545 * Sets the PCM sync identifier for the card.
547 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
549 struct snd_pcm_runtime *runtime = substream->runtime;
551 runtime->sync.id32[0] = substream->pcm->card->number;
552 runtime->sync.id32[1] = -1;
553 runtime->sync.id32[2] = -1;
554 runtime->sync.id32[3] = -1;
557 EXPORT_SYMBOL(snd_pcm_set_sync);
560 * Standard ioctl routine
563 static inline unsigned int div32(unsigned int a, unsigned int b,
574 static inline unsigned int div_down(unsigned int a, unsigned int b)
581 static inline unsigned int div_up(unsigned int a, unsigned int b)
593 static inline unsigned int mul(unsigned int a, unsigned int b)
597 if (div_down(UINT_MAX, a) < b)
602 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
603 unsigned int c, unsigned int *r)
605 u_int64_t n = (u_int64_t) a * b;
611 n = div_u64_rem(n, c, r);
620 * snd_interval_refine - refine the interval value of configurator
621 * @i: the interval value to refine
622 * @v: the interval value to refer to
624 * Refines the interval value with the reference value.
625 * The interval is changed to the range satisfying both intervals.
626 * The interval status (min, max, integer, etc.) are evaluated.
628 * Returns non-zero if the value is changed, zero if not changed.
630 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
633 if (snd_BUG_ON(snd_interval_empty(i)))
635 if (i->min < v->min) {
637 i->openmin = v->openmin;
639 } else if (i->min == v->min && !i->openmin && v->openmin) {
643 if (i->max > v->max) {
645 i->openmax = v->openmax;
647 } else if (i->max == v->max && !i->openmax && v->openmax) {
651 if (!i->integer && v->integer) {
664 } else if (!i->openmin && !i->openmax && i->min == i->max)
666 if (snd_interval_checkempty(i)) {
667 snd_interval_none(i);
673 EXPORT_SYMBOL(snd_interval_refine);
675 static int snd_interval_refine_first(struct snd_interval *i)
677 if (snd_BUG_ON(snd_interval_empty(i)))
679 if (snd_interval_single(i))
682 i->openmax = i->openmin;
688 static int snd_interval_refine_last(struct snd_interval *i)
690 if (snd_BUG_ON(snd_interval_empty(i)))
692 if (snd_interval_single(i))
695 i->openmin = i->openmax;
701 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
703 if (a->empty || b->empty) {
704 snd_interval_none(c);
708 c->min = mul(a->min, b->min);
709 c->openmin = (a->openmin || b->openmin);
710 c->max = mul(a->max, b->max);
711 c->openmax = (a->openmax || b->openmax);
712 c->integer = (a->integer && b->integer);
716 * snd_interval_div - refine the interval value with division
723 * Returns non-zero if the value is changed, zero if not changed.
725 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
728 if (a->empty || b->empty) {
729 snd_interval_none(c);
733 c->min = div32(a->min, b->max, &r);
734 c->openmin = (r || a->openmin || b->openmax);
736 c->max = div32(a->max, b->min, &r);
741 c->openmax = (a->openmax || b->openmin);
750 * snd_interval_muldivk - refine the interval value
753 * @k: divisor (as integer)
758 * Returns non-zero if the value is changed, zero if not changed.
760 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
761 unsigned int k, struct snd_interval *c)
764 if (a->empty || b->empty) {
765 snd_interval_none(c);
769 c->min = muldiv32(a->min, b->min, k, &r);
770 c->openmin = (r || a->openmin || b->openmin);
771 c->max = muldiv32(a->max, b->max, k, &r);
776 c->openmax = (a->openmax || b->openmax);
781 * snd_interval_mulkdiv - refine the interval value
783 * @k: dividend 2 (as integer)
789 * Returns non-zero if the value is changed, zero if not changed.
791 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
792 const struct snd_interval *b, struct snd_interval *c)
795 if (a->empty || b->empty) {
796 snd_interval_none(c);
800 c->min = muldiv32(a->min, k, b->max, &r);
801 c->openmin = (r || a->openmin || b->openmax);
803 c->max = muldiv32(a->max, k, b->min, &r);
808 c->openmax = (a->openmax || b->openmin);
820 * snd_interval_ratnum - refine the interval value
821 * @i: interval to refine
822 * @rats_count: number of ratnum_t
823 * @rats: ratnum_t array
824 * @nump: pointer to store the resultant numerator
825 * @denp: pointer to store the resultant denominator
827 * Returns non-zero if the value is changed, zero if not changed.
829 int snd_interval_ratnum(struct snd_interval *i,
830 unsigned int rats_count, struct snd_ratnum *rats,
831 unsigned int *nump, unsigned int *denp)
833 unsigned int best_num, best_den;
836 struct snd_interval t;
838 unsigned int result_num, result_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->min;
849 den = div_up(num, q);
850 if (den < rats[k].den_min)
852 if (den > rats[k].den_max)
853 den = rats[k].den_max;
856 r = (den - rats[k].den_min) % rats[k].den_step;
860 diff = num - q * den;
864 diff * best_den < best_diff * den) {
874 t.min = div_down(best_num, best_den);
875 t.openmin = !!(best_num % best_den);
877 result_num = best_num;
878 result_diff = best_diff;
879 result_den = best_den;
880 best_num = best_den = best_diff = 0;
881 for (k = 0; k < rats_count; ++k) {
882 unsigned int num = rats[k].num;
884 unsigned int q = i->max;
890 den = div_down(num, q);
891 if (den > rats[k].den_max)
893 if (den < rats[k].den_min)
894 den = rats[k].den_min;
897 r = (den - rats[k].den_min) % rats[k].den_step;
899 den += rats[k].den_step - r;
901 diff = q * den - num;
905 diff * best_den < best_diff * den) {
915 t.max = div_up(best_num, best_den);
916 t.openmax = !!(best_num % best_den);
918 err = snd_interval_refine(i, &t);
922 if (snd_interval_single(i)) {
923 if (best_diff * result_den < result_diff * best_den) {
924 result_num = best_num;
925 result_den = best_den;
935 EXPORT_SYMBOL(snd_interval_ratnum);
938 * snd_interval_ratden - refine the interval value
939 * @i: interval to refine
940 * @rats_count: number of struct ratden
941 * @rats: struct ratden array
942 * @nump: pointer to store the resultant numerator
943 * @denp: pointer to store the resultant denominator
945 * Returns non-zero if the value is changed, zero if not changed.
947 static int snd_interval_ratden(struct snd_interval *i,
948 unsigned int rats_count, struct snd_ratden *rats,
949 unsigned int *nump, unsigned int *denp)
951 unsigned int best_num, best_diff, best_den;
953 struct snd_interval t;
956 best_num = best_den = best_diff = 0;
957 for (k = 0; k < rats_count; ++k) {
959 unsigned int den = rats[k].den;
960 unsigned int q = i->min;
963 if (num > rats[k].num_max)
965 if (num < rats[k].num_min)
966 num = rats[k].num_max;
969 r = (num - rats[k].num_min) % rats[k].num_step;
971 num += rats[k].num_step - r;
973 diff = num - q * den;
975 diff * best_den < best_diff * den) {
985 t.min = div_down(best_num, best_den);
986 t.openmin = !!(best_num % best_den);
988 best_num = best_den = best_diff = 0;
989 for (k = 0; k < rats_count; ++k) {
991 unsigned int den = rats[k].den;
992 unsigned int q = i->max;
995 if (num < rats[k].num_min)
997 if (num > rats[k].num_max)
998 num = rats[k].num_max;
1001 r = (num - rats[k].num_min) % rats[k].num_step;
1005 diff = q * den - num;
1006 if (best_num == 0 ||
1007 diff * best_den < best_diff * den) {
1013 if (best_den == 0) {
1017 t.max = div_up(best_num, best_den);
1018 t.openmax = !!(best_num % best_den);
1020 err = snd_interval_refine(i, &t);
1024 if (snd_interval_single(i)) {
1034 * snd_interval_list - refine the interval value from the list
1035 * @i: the interval value to refine
1036 * @count: the number of elements in the list
1037 * @list: the value list
1038 * @mask: the bit-mask to evaluate
1040 * Refines the interval value from the list.
1041 * When mask is non-zero, only the elements corresponding to bit 1 are
1044 * Returns non-zero if the value is changed, zero if not changed.
1046 int snd_interval_list(struct snd_interval *i, unsigned int count,
1047 const unsigned int *list, unsigned int mask)
1050 struct snd_interval list_range;
1056 snd_interval_any(&list_range);
1057 list_range.min = UINT_MAX;
1059 for (k = 0; k < count; k++) {
1060 if (mask && !(mask & (1 << k)))
1062 if (!snd_interval_test(i, list[k]))
1064 list_range.min = min(list_range.min, list[k]);
1065 list_range.max = max(list_range.max, list[k]);
1067 return snd_interval_refine(i, &list_range);
1070 EXPORT_SYMBOL(snd_interval_list);
1072 static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
1076 n = (i->min - min) % step;
1077 if (n != 0 || i->openmin) {
1081 n = (i->max - min) % step;
1082 if (n != 0 || i->openmax) {
1086 if (snd_interval_checkempty(i)) {
1093 /* Info constraints helpers */
1096 * snd_pcm_hw_rule_add - add the hw-constraint rule
1097 * @runtime: the pcm runtime instance
1098 * @cond: condition bits
1099 * @var: the variable to evaluate
1100 * @func: the evaluation function
1101 * @private: the private data pointer passed to function
1102 * @dep: the dependent variables
1104 * Returns zero if successful, or a negative error code on failure.
1106 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1108 snd_pcm_hw_rule_func_t func, void *private,
1111 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1112 struct snd_pcm_hw_rule *c;
1115 va_start(args, dep);
1116 if (constrs->rules_num >= constrs->rules_all) {
1117 struct snd_pcm_hw_rule *new;
1118 unsigned int new_rules = constrs->rules_all + 16;
1119 new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1124 if (constrs->rules) {
1125 memcpy(new, constrs->rules,
1126 constrs->rules_num * sizeof(*c));
1127 kfree(constrs->rules);
1129 constrs->rules = new;
1130 constrs->rules_all = new_rules;
1132 c = &constrs->rules[constrs->rules_num];
1136 c->private = private;
1139 if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1146 dep = va_arg(args, int);
1148 constrs->rules_num++;
1153 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1156 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1157 * @runtime: PCM runtime instance
1158 * @var: hw_params variable to apply the mask
1159 * @mask: the bitmap mask
1161 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1163 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1166 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1167 struct snd_mask *maskp = constrs_mask(constrs, var);
1168 *maskp->bits &= mask;
1169 memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1170 if (*maskp->bits == 0)
1176 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1177 * @runtime: PCM runtime instance
1178 * @var: hw_params variable to apply the mask
1179 * @mask: the 64bit bitmap mask
1181 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1183 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1186 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1187 struct snd_mask *maskp = constrs_mask(constrs, var);
1188 maskp->bits[0] &= (u_int32_t)mask;
1189 maskp->bits[1] &= (u_int32_t)(mask >> 32);
1190 memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1191 if (! maskp->bits[0] && ! maskp->bits[1])
1197 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1198 * @runtime: PCM runtime instance
1199 * @var: hw_params variable to apply the integer constraint
1201 * Apply the constraint of integer to an interval parameter.
1203 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1205 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1206 return snd_interval_setinteger(constrs_interval(constrs, var));
1209 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1212 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1213 * @runtime: PCM runtime instance
1214 * @var: hw_params variable to apply the range
1215 * @min: the minimal value
1216 * @max: the maximal value
1218 * Apply the min/max range constraint to an interval parameter.
1220 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1221 unsigned int min, unsigned int max)
1223 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1224 struct snd_interval t;
1227 t.openmin = t.openmax = 0;
1229 return snd_interval_refine(constrs_interval(constrs, var), &t);
1232 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1234 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1235 struct snd_pcm_hw_rule *rule)
1237 struct snd_pcm_hw_constraint_list *list = rule->private;
1238 return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1243 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1244 * @runtime: PCM runtime instance
1245 * @cond: condition bits
1246 * @var: hw_params variable to apply the list constraint
1249 * Apply the list of constraints to an interval parameter.
1251 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1253 snd_pcm_hw_param_t var,
1254 const struct snd_pcm_hw_constraint_list *l)
1256 return snd_pcm_hw_rule_add(runtime, cond, var,
1257 snd_pcm_hw_rule_list, (void *)l,
1261 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1263 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1264 struct snd_pcm_hw_rule *rule)
1266 struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1267 unsigned int num = 0, den = 0;
1269 err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1270 r->nrats, r->rats, &num, &den);
1271 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1272 params->rate_num = num;
1273 params->rate_den = den;
1279 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1280 * @runtime: PCM runtime instance
1281 * @cond: condition bits
1282 * @var: hw_params variable to apply the ratnums constraint
1283 * @r: struct snd_ratnums constriants
1285 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1287 snd_pcm_hw_param_t var,
1288 struct snd_pcm_hw_constraint_ratnums *r)
1290 return snd_pcm_hw_rule_add(runtime, cond, var,
1291 snd_pcm_hw_rule_ratnums, r,
1295 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1297 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1298 struct snd_pcm_hw_rule *rule)
1300 struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1301 unsigned int num = 0, den = 0;
1302 int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1303 r->nrats, r->rats, &num, &den);
1304 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1305 params->rate_num = num;
1306 params->rate_den = den;
1312 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1313 * @runtime: PCM runtime instance
1314 * @cond: condition bits
1315 * @var: hw_params variable to apply the ratdens constraint
1316 * @r: struct snd_ratdens constriants
1318 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1320 snd_pcm_hw_param_t var,
1321 struct snd_pcm_hw_constraint_ratdens *r)
1323 return snd_pcm_hw_rule_add(runtime, cond, var,
1324 snd_pcm_hw_rule_ratdens, r,
1328 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1330 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1331 struct snd_pcm_hw_rule *rule)
1333 unsigned int l = (unsigned long) rule->private;
1334 int width = l & 0xffff;
1335 unsigned int msbits = l >> 16;
1336 struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1337 if (snd_interval_single(i) && snd_interval_value(i) == width)
1338 params->msbits = msbits;
1343 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1344 * @runtime: PCM runtime instance
1345 * @cond: condition bits
1346 * @width: sample bits width
1347 * @msbits: msbits width
1349 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1352 unsigned int msbits)
1354 unsigned long l = (msbits << 16) | width;
1355 return snd_pcm_hw_rule_add(runtime, cond, -1,
1356 snd_pcm_hw_rule_msbits,
1358 SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1361 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1363 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1364 struct snd_pcm_hw_rule *rule)
1366 unsigned long step = (unsigned long) rule->private;
1367 return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1371 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1372 * @runtime: PCM runtime instance
1373 * @cond: condition bits
1374 * @var: hw_params variable to apply the step constraint
1377 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1379 snd_pcm_hw_param_t var,
1382 return snd_pcm_hw_rule_add(runtime, cond, var,
1383 snd_pcm_hw_rule_step, (void *) step,
1387 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1389 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1391 static unsigned int pow2_sizes[] = {
1392 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1393 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1394 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1395 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1397 return snd_interval_list(hw_param_interval(params, rule->var),
1398 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1402 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1403 * @runtime: PCM runtime instance
1404 * @cond: condition bits
1405 * @var: hw_params variable to apply the power-of-2 constraint
1407 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1409 snd_pcm_hw_param_t var)
1411 return snd_pcm_hw_rule_add(runtime, cond, var,
1412 snd_pcm_hw_rule_pow2, NULL,
1416 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1418 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1419 struct snd_pcm_hw_rule *rule)
1421 unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1422 struct snd_interval *rate;
1424 rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1425 return snd_interval_list(rate, 1, &base_rate, 0);
1429 * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1430 * @runtime: PCM runtime instance
1431 * @base_rate: the rate at which the hardware does not resample
1433 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1434 unsigned int base_rate)
1436 return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1437 SNDRV_PCM_HW_PARAM_RATE,
1438 snd_pcm_hw_rule_noresample_func,
1439 (void *)(uintptr_t)base_rate,
1440 SNDRV_PCM_HW_PARAM_RATE, -1);
1442 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1444 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1445 snd_pcm_hw_param_t var)
1447 if (hw_is_mask(var)) {
1448 snd_mask_any(hw_param_mask(params, var));
1449 params->cmask |= 1 << var;
1450 params->rmask |= 1 << var;
1453 if (hw_is_interval(var)) {
1454 snd_interval_any(hw_param_interval(params, var));
1455 params->cmask |= 1 << var;
1456 params->rmask |= 1 << var;
1462 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1465 memset(params, 0, sizeof(*params));
1466 for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1467 _snd_pcm_hw_param_any(params, k);
1468 for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1469 _snd_pcm_hw_param_any(params, k);
1473 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1476 * snd_pcm_hw_param_value - return @params field @var value
1477 * @params: the hw_params instance
1478 * @var: parameter to retrieve
1479 * @dir: pointer to the direction (-1,0,1) or %NULL
1481 * Return the value for field @var if it's fixed in configuration space
1482 * defined by @params. Return -%EINVAL otherwise.
1484 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1485 snd_pcm_hw_param_t var, int *dir)
1487 if (hw_is_mask(var)) {
1488 const struct snd_mask *mask = hw_param_mask_c(params, var);
1489 if (!snd_mask_single(mask))
1493 return snd_mask_value(mask);
1495 if (hw_is_interval(var)) {
1496 const struct snd_interval *i = hw_param_interval_c(params, var);
1497 if (!snd_interval_single(i))
1501 return snd_interval_value(i);
1506 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1508 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1509 snd_pcm_hw_param_t var)
1511 if (hw_is_mask(var)) {
1512 snd_mask_none(hw_param_mask(params, var));
1513 params->cmask |= 1 << var;
1514 params->rmask |= 1 << var;
1515 } else if (hw_is_interval(var)) {
1516 snd_interval_none(hw_param_interval(params, var));
1517 params->cmask |= 1 << var;
1518 params->rmask |= 1 << var;
1524 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1526 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1527 snd_pcm_hw_param_t var)
1530 if (hw_is_mask(var))
1531 changed = snd_mask_refine_first(hw_param_mask(params, var));
1532 else if (hw_is_interval(var))
1533 changed = snd_interval_refine_first(hw_param_interval(params, var));
1537 params->cmask |= 1 << var;
1538 params->rmask |= 1 << var;
1545 * snd_pcm_hw_param_first - refine config space and return minimum value
1546 * @pcm: PCM instance
1547 * @params: the hw_params instance
1548 * @var: parameter to retrieve
1549 * @dir: pointer to the direction (-1,0,1) or %NULL
1551 * Inside configuration space defined by @params remove from @var all
1552 * values > minimum. Reduce configuration space accordingly.
1553 * Return the minimum.
1555 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1556 struct snd_pcm_hw_params *params,
1557 snd_pcm_hw_param_t var, int *dir)
1559 int changed = _snd_pcm_hw_param_first(params, var);
1562 if (params->rmask) {
1563 int err = snd_pcm_hw_refine(pcm, params);
1564 if (snd_BUG_ON(err < 0))
1567 return snd_pcm_hw_param_value(params, var, dir);
1570 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1572 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1573 snd_pcm_hw_param_t var)
1576 if (hw_is_mask(var))
1577 changed = snd_mask_refine_last(hw_param_mask(params, var));
1578 else if (hw_is_interval(var))
1579 changed = snd_interval_refine_last(hw_param_interval(params, var));
1583 params->cmask |= 1 << var;
1584 params->rmask |= 1 << var;
1591 * snd_pcm_hw_param_last - refine config space and return maximum value
1592 * @pcm: PCM instance
1593 * @params: the hw_params instance
1594 * @var: parameter to retrieve
1595 * @dir: pointer to the direction (-1,0,1) or %NULL
1597 * Inside configuration space defined by @params remove from @var all
1598 * values < maximum. Reduce configuration space accordingly.
1599 * Return the maximum.
1601 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1602 struct snd_pcm_hw_params *params,
1603 snd_pcm_hw_param_t var, int *dir)
1605 int changed = _snd_pcm_hw_param_last(params, var);
1608 if (params->rmask) {
1609 int err = snd_pcm_hw_refine(pcm, params);
1610 if (snd_BUG_ON(err < 0))
1613 return snd_pcm_hw_param_value(params, var, dir);
1616 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1619 * snd_pcm_hw_param_choose - choose a configuration defined by @params
1620 * @pcm: PCM instance
1621 * @params: the hw_params instance
1623 * Choose one configuration from configuration space defined by @params.
1624 * The configuration chosen is that obtained fixing in this order:
1625 * first access, first format, first subformat, min channels,
1626 * min rate, min period time, max buffer size, min tick time
1628 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1629 struct snd_pcm_hw_params *params)
1631 static int vars[] = {
1632 SNDRV_PCM_HW_PARAM_ACCESS,
1633 SNDRV_PCM_HW_PARAM_FORMAT,
1634 SNDRV_PCM_HW_PARAM_SUBFORMAT,
1635 SNDRV_PCM_HW_PARAM_CHANNELS,
1636 SNDRV_PCM_HW_PARAM_RATE,
1637 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1638 SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1639 SNDRV_PCM_HW_PARAM_TICK_TIME,
1644 for (v = vars; *v != -1; v++) {
1645 if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1646 err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1648 err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1649 if (snd_BUG_ON(err < 0))
1655 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1658 struct snd_pcm_runtime *runtime = substream->runtime;
1659 unsigned long flags;
1660 snd_pcm_stream_lock_irqsave(substream, flags);
1661 if (snd_pcm_running(substream) &&
1662 snd_pcm_update_hw_ptr(substream) >= 0)
1663 runtime->status->hw_ptr %= runtime->buffer_size;
1665 runtime->status->hw_ptr = 0;
1666 snd_pcm_stream_unlock_irqrestore(substream, flags);
1670 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1673 struct snd_pcm_channel_info *info = arg;
1674 struct snd_pcm_runtime *runtime = substream->runtime;
1676 if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1680 width = snd_pcm_format_physical_width(runtime->format);
1684 switch (runtime->access) {
1685 case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1686 case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1687 info->first = info->channel * width;
1688 info->step = runtime->channels * width;
1690 case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1691 case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1693 size_t size = runtime->dma_bytes / runtime->channels;
1694 info->first = info->channel * size * 8;
1705 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1708 struct snd_pcm_hw_params *params = arg;
1709 snd_pcm_format_t format;
1710 int channels, width;
1712 params->fifo_size = substream->runtime->hw.fifo_size;
1713 if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1714 format = params_format(params);
1715 channels = params_channels(params);
1716 width = snd_pcm_format_physical_width(format);
1717 params->fifo_size /= width * channels;
1723 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1724 * @substream: the pcm substream instance
1725 * @cmd: ioctl command
1726 * @arg: ioctl argument
1728 * Processes the generic ioctl commands for PCM.
1729 * Can be passed as the ioctl callback for PCM ops.
1731 * Returns zero if successful, or a negative error code on failure.
1733 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1734 unsigned int cmd, void *arg)
1737 case SNDRV_PCM_IOCTL1_INFO:
1739 case SNDRV_PCM_IOCTL1_RESET:
1740 return snd_pcm_lib_ioctl_reset(substream, arg);
1741 case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1742 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1743 case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1744 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1749 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1752 * snd_pcm_period_elapsed - update the pcm status for the next period
1753 * @substream: the pcm substream instance
1755 * This function is called from the interrupt handler when the
1756 * PCM has processed the period size. It will update the current
1757 * pointer, wake up sleepers, etc.
1759 * Even if more than one periods have elapsed since the last call, you
1760 * have to call this only once.
1762 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1764 struct snd_pcm_runtime *runtime;
1765 unsigned long flags;
1767 if (PCM_RUNTIME_CHECK(substream))
1769 runtime = substream->runtime;
1771 if (runtime->transfer_ack_begin)
1772 runtime->transfer_ack_begin(substream);
1774 snd_pcm_stream_lock_irqsave(substream, flags);
1775 if (!snd_pcm_running(substream) ||
1776 snd_pcm_update_hw_ptr0(substream, 1) < 0)
1779 if (substream->timer_running)
1780 snd_timer_interrupt(substream->timer, 1);
1782 snd_pcm_stream_unlock_irqrestore(substream, flags);
1783 if (runtime->transfer_ack_end)
1784 runtime->transfer_ack_end(substream);
1785 kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1788 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1791 * Wait until avail_min data becomes available
1792 * Returns a negative error code if any error occurs during operation.
1793 * The available space is stored on availp. When err = 0 and avail = 0
1794 * on the capture stream, it indicates the stream is in DRAINING state.
1796 static int wait_for_avail(struct snd_pcm_substream *substream,
1797 snd_pcm_uframes_t *availp)
1799 struct snd_pcm_runtime *runtime = substream->runtime;
1800 int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1803 snd_pcm_uframes_t avail = 0;
1804 long wait_time, tout;
1806 init_waitqueue_entry(&wait, current);
1807 set_current_state(TASK_INTERRUPTIBLE);
1808 add_wait_queue(&runtime->tsleep, &wait);
1810 if (runtime->no_period_wakeup)
1811 wait_time = MAX_SCHEDULE_TIMEOUT;
1814 if (runtime->rate) {
1815 long t = runtime->period_size * 2 / runtime->rate;
1816 wait_time = max(t, wait_time);
1818 wait_time = msecs_to_jiffies(wait_time * 1000);
1822 if (signal_pending(current)) {
1828 * We need to check if space became available already
1829 * (and thus the wakeup happened already) first to close
1830 * the race of space already having become available.
1831 * This check must happen after been added to the waitqueue
1832 * and having current state be INTERRUPTIBLE.
1835 avail = snd_pcm_playback_avail(runtime);
1837 avail = snd_pcm_capture_avail(runtime);
1838 if (avail >= runtime->twake)
1840 snd_pcm_stream_unlock_irq(substream);
1842 tout = schedule_timeout(wait_time);
1844 snd_pcm_stream_lock_irq(substream);
1845 set_current_state(TASK_INTERRUPTIBLE);
1846 switch (runtime->status->state) {
1847 case SNDRV_PCM_STATE_SUSPENDED:
1850 case SNDRV_PCM_STATE_XRUN:
1853 case SNDRV_PCM_STATE_DRAINING:
1857 avail = 0; /* indicate draining */
1859 case SNDRV_PCM_STATE_OPEN:
1860 case SNDRV_PCM_STATE_SETUP:
1861 case SNDRV_PCM_STATE_DISCONNECTED:
1866 snd_printd("%s write error (DMA or IRQ trouble?)\n",
1867 is_playback ? "playback" : "capture");
1873 set_current_state(TASK_RUNNING);
1874 remove_wait_queue(&runtime->tsleep, &wait);
1879 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1881 unsigned long data, unsigned int off,
1882 snd_pcm_uframes_t frames)
1884 struct snd_pcm_runtime *runtime = substream->runtime;
1886 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1887 if (substream->ops->copy) {
1888 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1891 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1892 if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1898 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1899 unsigned long data, unsigned int off,
1900 snd_pcm_uframes_t size);
1902 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1904 snd_pcm_uframes_t size,
1906 transfer_f transfer)
1908 struct snd_pcm_runtime *runtime = substream->runtime;
1909 snd_pcm_uframes_t xfer = 0;
1910 snd_pcm_uframes_t offset = 0;
1911 snd_pcm_uframes_t avail;
1917 snd_pcm_stream_lock_irq(substream);
1918 switch (runtime->status->state) {
1919 case SNDRV_PCM_STATE_PREPARED:
1920 case SNDRV_PCM_STATE_RUNNING:
1921 case SNDRV_PCM_STATE_PAUSED:
1923 case SNDRV_PCM_STATE_XRUN:
1926 case SNDRV_PCM_STATE_SUSPENDED:
1934 runtime->twake = runtime->control->avail_min ? : 1;
1935 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1936 snd_pcm_update_hw_ptr(substream);
1937 avail = snd_pcm_playback_avail(runtime);
1939 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1940 snd_pcm_uframes_t cont;
1946 runtime->twake = min_t(snd_pcm_uframes_t, size,
1947 runtime->control->avail_min ? : 1);
1948 err = wait_for_avail(substream, &avail);
1952 frames = size > avail ? avail : size;
1953 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1956 if (snd_BUG_ON(!frames)) {
1958 snd_pcm_stream_unlock_irq(substream);
1961 appl_ptr = runtime->control->appl_ptr;
1962 appl_ofs = appl_ptr % runtime->buffer_size;
1963 snd_pcm_stream_unlock_irq(substream);
1964 err = transfer(substream, appl_ofs, data, offset, frames);
1965 snd_pcm_stream_lock_irq(substream);
1968 switch (runtime->status->state) {
1969 case SNDRV_PCM_STATE_XRUN:
1972 case SNDRV_PCM_STATE_SUSPENDED:
1979 if (appl_ptr >= runtime->boundary)
1980 appl_ptr -= runtime->boundary;
1981 runtime->control->appl_ptr = appl_ptr;
1982 if (substream->ops->ack)
1983 substream->ops->ack(substream);
1989 if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1990 snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1991 err = snd_pcm_start(substream);
1998 if (xfer > 0 && err >= 0)
1999 snd_pcm_update_state(substream, runtime);
2000 snd_pcm_stream_unlock_irq(substream);
2001 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2004 /* sanity-check for read/write methods */
2005 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2007 struct snd_pcm_runtime *runtime;
2008 if (PCM_RUNTIME_CHECK(substream))
2010 runtime = substream->runtime;
2011 if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
2013 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2018 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
2020 struct snd_pcm_runtime *runtime;
2024 err = pcm_sanity_check(substream);
2027 runtime = substream->runtime;
2028 nonblock = !!(substream->f_flags & O_NONBLOCK);
2030 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2031 runtime->channels > 1)
2033 return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
2034 snd_pcm_lib_write_transfer);
2037 EXPORT_SYMBOL(snd_pcm_lib_write);
2039 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
2041 unsigned long data, unsigned int off,
2042 snd_pcm_uframes_t frames)
2044 struct snd_pcm_runtime *runtime = substream->runtime;
2046 void __user **bufs = (void __user **)data;
2047 int channels = runtime->channels;
2049 if (substream->ops->copy) {
2050 if (snd_BUG_ON(!substream->ops->silence))
2052 for (c = 0; c < channels; ++c, ++bufs) {
2053 if (*bufs == NULL) {
2054 if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
2057 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2058 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2063 /* default transfer behaviour */
2064 size_t dma_csize = runtime->dma_bytes / channels;
2065 for (c = 0; c < channels; ++c, ++bufs) {
2066 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2067 if (*bufs == NULL) {
2068 snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
2070 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2071 if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
2079 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
2081 snd_pcm_uframes_t frames)
2083 struct snd_pcm_runtime *runtime;
2087 err = pcm_sanity_check(substream);
2090 runtime = substream->runtime;
2091 nonblock = !!(substream->f_flags & O_NONBLOCK);
2093 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2095 return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2096 nonblock, snd_pcm_lib_writev_transfer);
2099 EXPORT_SYMBOL(snd_pcm_lib_writev);
2101 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
2103 unsigned long data, unsigned int off,
2104 snd_pcm_uframes_t frames)
2106 struct snd_pcm_runtime *runtime = substream->runtime;
2108 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2109 if (substream->ops->copy) {
2110 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2113 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2114 if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2120 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2122 snd_pcm_uframes_t size,
2124 transfer_f transfer)
2126 struct snd_pcm_runtime *runtime = substream->runtime;
2127 snd_pcm_uframes_t xfer = 0;
2128 snd_pcm_uframes_t offset = 0;
2129 snd_pcm_uframes_t avail;
2135 snd_pcm_stream_lock_irq(substream);
2136 switch (runtime->status->state) {
2137 case SNDRV_PCM_STATE_PREPARED:
2138 if (size >= runtime->start_threshold) {
2139 err = snd_pcm_start(substream);
2144 case SNDRV_PCM_STATE_DRAINING:
2145 case SNDRV_PCM_STATE_RUNNING:
2146 case SNDRV_PCM_STATE_PAUSED:
2148 case SNDRV_PCM_STATE_XRUN:
2151 case SNDRV_PCM_STATE_SUSPENDED:
2159 runtime->twake = runtime->control->avail_min ? : 1;
2160 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2161 snd_pcm_update_hw_ptr(substream);
2162 avail = snd_pcm_capture_avail(runtime);
2164 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2165 snd_pcm_uframes_t cont;
2167 if (runtime->status->state ==
2168 SNDRV_PCM_STATE_DRAINING) {
2169 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2176 runtime->twake = min_t(snd_pcm_uframes_t, size,
2177 runtime->control->avail_min ? : 1);
2178 err = wait_for_avail(substream, &avail);
2182 continue; /* draining */
2184 frames = size > avail ? avail : size;
2185 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2188 if (snd_BUG_ON(!frames)) {
2190 snd_pcm_stream_unlock_irq(substream);
2193 appl_ptr = runtime->control->appl_ptr;
2194 appl_ofs = appl_ptr % runtime->buffer_size;
2195 snd_pcm_stream_unlock_irq(substream);
2196 err = transfer(substream, appl_ofs, data, offset, frames);
2197 snd_pcm_stream_lock_irq(substream);
2200 switch (runtime->status->state) {
2201 case SNDRV_PCM_STATE_XRUN:
2204 case SNDRV_PCM_STATE_SUSPENDED:
2211 if (appl_ptr >= runtime->boundary)
2212 appl_ptr -= runtime->boundary;
2213 runtime->control->appl_ptr = appl_ptr;
2214 if (substream->ops->ack)
2215 substream->ops->ack(substream);
2224 if (xfer > 0 && err >= 0)
2225 snd_pcm_update_state(substream, runtime);
2226 snd_pcm_stream_unlock_irq(substream);
2227 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2230 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2232 struct snd_pcm_runtime *runtime;
2236 err = pcm_sanity_check(substream);
2239 runtime = substream->runtime;
2240 nonblock = !!(substream->f_flags & O_NONBLOCK);
2241 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2243 return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2246 EXPORT_SYMBOL(snd_pcm_lib_read);
2248 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2250 unsigned long data, unsigned int off,
2251 snd_pcm_uframes_t frames)
2253 struct snd_pcm_runtime *runtime = substream->runtime;
2255 void __user **bufs = (void __user **)data;
2256 int channels = runtime->channels;
2258 if (substream->ops->copy) {
2259 for (c = 0; c < channels; ++c, ++bufs) {
2263 buf = *bufs + samples_to_bytes(runtime, off);
2264 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2268 snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2269 for (c = 0; c < channels; ++c, ++bufs) {
2275 hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2276 buf = *bufs + samples_to_bytes(runtime, off);
2277 if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2284 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2286 snd_pcm_uframes_t frames)
2288 struct snd_pcm_runtime *runtime;
2292 err = pcm_sanity_check(substream);
2295 runtime = substream->runtime;
2296 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2299 nonblock = !!(substream->f_flags & O_NONBLOCK);
2300 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2302 return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2305 EXPORT_SYMBOL(snd_pcm_lib_readv);
2308 * standard channel mapping helpers
2311 /* default channel maps for multi-channel playbacks, up to 8 channels */
2312 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2314 .map = { SNDRV_CHMAP_MONO } },
2316 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2318 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2319 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2321 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2322 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2323 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2325 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2326 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2327 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2328 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2331 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2333 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2334 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2336 .map = { SNDRV_CHMAP_MONO } },
2338 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2340 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2341 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2343 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2344 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2345 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2347 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2348 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2349 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2350 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2353 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2355 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2357 if (ch > info->max_channels)
2359 return !info->channel_mask || (info->channel_mask & (1U << ch));
2362 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2363 struct snd_ctl_elem_info *uinfo)
2365 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2367 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2369 uinfo->count = info->max_channels;
2370 uinfo->value.integer.min = 0;
2371 uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2375 /* get callback for channel map ctl element
2376 * stores the channel position firstly matching with the current channels
2378 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2379 struct snd_ctl_elem_value *ucontrol)
2381 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2382 unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2383 struct snd_pcm_substream *substream;
2384 const struct snd_pcm_chmap_elem *map;
2386 if (snd_BUG_ON(!info->chmap))
2388 substream = snd_pcm_chmap_substream(info, idx);
2391 memset(ucontrol->value.integer.value, 0,
2392 sizeof(ucontrol->value.integer.value));
2393 if (!substream->runtime)
2394 return 0; /* no channels set */
2395 for (map = info->chmap; map->channels; map++) {
2397 if (map->channels == substream->runtime->channels &&
2398 valid_chmap_channels(info, map->channels)) {
2399 for (i = 0; i < map->channels; i++)
2400 ucontrol->value.integer.value[i] = map->map[i];
2407 /* tlv callback for channel map ctl element
2408 * expands the pre-defined channel maps in a form of TLV
2410 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2411 unsigned int size, unsigned int __user *tlv)
2413 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2414 const struct snd_pcm_chmap_elem *map;
2415 unsigned int __user *dst;
2418 if (snd_BUG_ON(!info->chmap))
2422 if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2426 for (map = info->chmap; map->channels; map++) {
2427 int chs_bytes = map->channels * 4;
2428 if (!valid_chmap_channels(info, map->channels))
2432 if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2433 put_user(chs_bytes, dst + 1))
2438 if (size < chs_bytes)
2442 for (c = 0; c < map->channels; c++) {
2443 if (put_user(map->map[c], dst))
2448 if (put_user(count, tlv + 1))
2453 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2455 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2456 info->pcm->streams[info->stream].chmap_kctl = NULL;
2461 * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2462 * @pcm: the assigned PCM instance
2463 * @stream: stream direction
2464 * @chmap: channel map elements (for query)
2465 * @max_channels: the max number of channels for the stream
2466 * @private_value: the value passed to each kcontrol's private_value field
2467 * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2469 * Create channel-mapping control elements assigned to the given PCM stream(s).
2470 * Returns zero if succeed, or a negative error value.
2472 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2473 const struct snd_pcm_chmap_elem *chmap,
2475 unsigned long private_value,
2476 struct snd_pcm_chmap **info_ret)
2478 struct snd_pcm_chmap *info;
2479 struct snd_kcontrol_new knew = {
2480 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
2481 .access = SNDRV_CTL_ELEM_ACCESS_READ |
2482 SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2483 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2484 .info = pcm_chmap_ctl_info,
2485 .get = pcm_chmap_ctl_get,
2486 .tlv.c = pcm_chmap_ctl_tlv,
2490 info = kzalloc(sizeof(*info), GFP_KERNEL);
2494 info->stream = stream;
2495 info->chmap = chmap;
2496 info->max_channels = max_channels;
2497 if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2498 knew.name = "Playback Channel Map";
2500 knew.name = "Capture Channel Map";
2501 knew.device = pcm->device;
2502 knew.count = pcm->streams[stream].substream_count;
2503 knew.private_value = private_value;
2504 info->kctl = snd_ctl_new1(&knew, info);
2509 info->kctl->private_free = pcm_chmap_ctl_private_free;
2510 err = snd_ctl_add(pcm->card, info->kctl);
2513 pcm->streams[stream].chmap_kctl = info->kctl;
2518 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);