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 (snd_printd_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;
319 struct timespec audio_tstamp;
320 int crossed_boundary = 0;
322 old_hw_ptr = runtime->status->hw_ptr;
325 * group pointer, time and jiffies reads to allow for more
326 * accurate correlations/corrections.
327 * The values are stored at the end of this routine after
328 * corrections for hw_ptr position
330 pos = substream->ops->pointer(substream);
331 curr_jiffies = jiffies;
332 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
333 snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
335 if ((runtime->hw.info & SNDRV_PCM_INFO_HAS_WALL_CLOCK) &&
336 (substream->ops->wall_clock))
337 substream->ops->wall_clock(substream, &audio_tstamp);
340 if (pos == SNDRV_PCM_POS_XRUN) {
344 if (pos >= runtime->buffer_size) {
345 if (snd_printd_ratelimit()) {
347 snd_pcm_debug_name(substream, name, sizeof(name));
348 xrun_log_show(substream);
349 snd_printd(KERN_ERR "BUG: %s, pos = %ld, "
350 "buffer size = %ld, period size = %ld\n",
351 name, pos, runtime->buffer_size,
352 runtime->period_size);
356 pos -= pos % runtime->min_align;
357 if (xrun_debug(substream, XRUN_DEBUG_LOG))
358 xrun_log(substream, pos, in_interrupt);
359 hw_base = runtime->hw_ptr_base;
360 new_hw_ptr = hw_base + pos;
362 /* we know that one period was processed */
363 /* delta = "expected next hw_ptr" for in_interrupt != 0 */
364 delta = runtime->hw_ptr_interrupt + runtime->period_size;
365 if (delta > new_hw_ptr) {
366 /* check for double acknowledged interrupts */
367 hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
368 if (hdelta > runtime->hw_ptr_buffer_jiffies/2) {
369 hw_base += runtime->buffer_size;
370 if (hw_base >= runtime->boundary) {
374 new_hw_ptr = hw_base + pos;
379 /* new_hw_ptr might be lower than old_hw_ptr in case when */
380 /* pointer crosses the end of the ring buffer */
381 if (new_hw_ptr < old_hw_ptr) {
382 hw_base += runtime->buffer_size;
383 if (hw_base >= runtime->boundary) {
387 new_hw_ptr = hw_base + pos;
390 delta = new_hw_ptr - old_hw_ptr;
392 delta += runtime->boundary;
393 if (xrun_debug(substream, in_interrupt ?
394 XRUN_DEBUG_PERIODUPDATE : XRUN_DEBUG_HWPTRUPDATE)) {
396 snd_pcm_debug_name(substream, name, sizeof(name));
397 snd_printd("%s_update: %s: pos=%u/%u/%u, "
398 "hwptr=%ld/%ld/%ld/%ld\n",
399 in_interrupt ? "period" : "hwptr",
402 (unsigned int)runtime->period_size,
403 (unsigned int)runtime->buffer_size,
404 (unsigned long)delta,
405 (unsigned long)old_hw_ptr,
406 (unsigned long)new_hw_ptr,
407 (unsigned long)runtime->hw_ptr_base);
410 if (runtime->no_period_wakeup) {
411 snd_pcm_sframes_t xrun_threshold;
413 * Without regular period interrupts, we have to check
414 * the elapsed time to detect xruns.
416 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
417 if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
419 hdelta = jdelta - delta * HZ / runtime->rate;
420 xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
421 while (hdelta > xrun_threshold) {
422 delta += runtime->buffer_size;
423 hw_base += runtime->buffer_size;
424 if (hw_base >= runtime->boundary) {
428 new_hw_ptr = hw_base + pos;
429 hdelta -= runtime->hw_ptr_buffer_jiffies;
434 /* something must be really wrong */
435 if (delta >= runtime->buffer_size + runtime->period_size) {
436 hw_ptr_error(substream,
437 "Unexpected hw_pointer value %s"
438 "(stream=%i, pos=%ld, new_hw_ptr=%ld, "
440 in_interrupt ? "[Q] " : "[P]",
441 substream->stream, (long)pos,
442 (long)new_hw_ptr, (long)old_hw_ptr);
446 /* Do jiffies check only in xrun_debug mode */
447 if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
448 goto no_jiffies_check;
450 /* Skip the jiffies check for hardwares with BATCH flag.
451 * Such hardware usually just increases the position at each IRQ,
452 * thus it can't give any strange position.
454 if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
455 goto no_jiffies_check;
457 if (hdelta < runtime->delay)
458 goto no_jiffies_check;
459 hdelta -= runtime->delay;
460 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
461 if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
463 (((runtime->period_size * HZ) / runtime->rate)
465 /* move new_hw_ptr according jiffies not pos variable */
466 new_hw_ptr = old_hw_ptr;
468 /* use loop to avoid checks for delta overflows */
469 /* the delta value is small or zero in most cases */
471 new_hw_ptr += runtime->period_size;
472 if (new_hw_ptr >= runtime->boundary) {
473 new_hw_ptr -= runtime->boundary;
478 /* align hw_base to buffer_size */
479 hw_ptr_error(substream,
480 "hw_ptr skipping! %s"
481 "(pos=%ld, delta=%ld, period=%ld, "
482 "jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
483 in_interrupt ? "[Q] " : "",
484 (long)pos, (long)hdelta,
485 (long)runtime->period_size, jdelta,
486 ((hdelta * HZ) / runtime->rate), hw_base,
487 (unsigned long)old_hw_ptr,
488 (unsigned long)new_hw_ptr);
489 /* reset values to proper state */
491 hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
494 if (delta > runtime->period_size + runtime->period_size / 2) {
495 hw_ptr_error(substream,
496 "Lost interrupts? %s"
497 "(stream=%i, delta=%ld, new_hw_ptr=%ld, "
499 in_interrupt ? "[Q] " : "",
500 substream->stream, (long)delta,
506 if (runtime->status->hw_ptr == new_hw_ptr)
509 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
510 runtime->silence_size > 0)
511 snd_pcm_playback_silence(substream, new_hw_ptr);
514 delta = new_hw_ptr - runtime->hw_ptr_interrupt;
516 delta += runtime->boundary;
517 delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
518 runtime->hw_ptr_interrupt += delta;
519 if (runtime->hw_ptr_interrupt >= runtime->boundary)
520 runtime->hw_ptr_interrupt -= runtime->boundary;
522 runtime->hw_ptr_base = hw_base;
523 runtime->status->hw_ptr = new_hw_ptr;
524 runtime->hw_ptr_jiffies = curr_jiffies;
525 if (crossed_boundary) {
526 snd_BUG_ON(crossed_boundary != 1);
527 runtime->hw_ptr_wrap += runtime->boundary;
529 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
530 runtime->status->tstamp = curr_tstamp;
532 if (!(runtime->hw.info & SNDRV_PCM_INFO_HAS_WALL_CLOCK)) {
534 * no wall clock available, provide audio timestamp
535 * derived from pointer position+delay
537 u64 audio_frames, audio_nsecs;
539 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
540 audio_frames = runtime->hw_ptr_wrap
541 + runtime->status->hw_ptr
544 audio_frames = runtime->hw_ptr_wrap
545 + runtime->status->hw_ptr
547 audio_nsecs = div_u64(audio_frames * 1000000000LL,
549 audio_tstamp = ns_to_timespec(audio_nsecs);
551 runtime->status->audio_tstamp = audio_tstamp;
554 return snd_pcm_update_state(substream, runtime);
557 /* CAUTION: call it with irq disabled */
558 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
560 return snd_pcm_update_hw_ptr0(substream, 0);
564 * snd_pcm_set_ops - set the PCM operators
565 * @pcm: the pcm instance
566 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
567 * @ops: the operator table
569 * Sets the given PCM operators to the pcm instance.
571 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
572 const struct snd_pcm_ops *ops)
574 struct snd_pcm_str *stream = &pcm->streams[direction];
575 struct snd_pcm_substream *substream;
577 for (substream = stream->substream; substream != NULL; substream = substream->next)
578 substream->ops = ops;
581 EXPORT_SYMBOL(snd_pcm_set_ops);
584 * snd_pcm_sync - set the PCM sync id
585 * @substream: the pcm substream
587 * Sets the PCM sync identifier for the card.
589 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
591 struct snd_pcm_runtime *runtime = substream->runtime;
593 runtime->sync.id32[0] = substream->pcm->card->number;
594 runtime->sync.id32[1] = -1;
595 runtime->sync.id32[2] = -1;
596 runtime->sync.id32[3] = -1;
599 EXPORT_SYMBOL(snd_pcm_set_sync);
602 * Standard ioctl routine
605 static inline unsigned int div32(unsigned int a, unsigned int b,
616 static inline unsigned int div_down(unsigned int a, unsigned int b)
623 static inline unsigned int div_up(unsigned int a, unsigned int b)
635 static inline unsigned int mul(unsigned int a, unsigned int b)
639 if (div_down(UINT_MAX, a) < b)
644 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
645 unsigned int c, unsigned int *r)
647 u_int64_t n = (u_int64_t) a * b;
653 n = div_u64_rem(n, c, r);
662 * snd_interval_refine - refine the interval value of configurator
663 * @i: the interval value to refine
664 * @v: the interval value to refer to
666 * Refines the interval value with the reference value.
667 * The interval is changed to the range satisfying both intervals.
668 * The interval status (min, max, integer, etc.) are evaluated.
670 * Return: Positive if the value is changed, zero if it's not changed, or a
671 * negative error code.
673 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
676 if (snd_BUG_ON(snd_interval_empty(i)))
678 if (i->min < v->min) {
680 i->openmin = v->openmin;
682 } else if (i->min == v->min && !i->openmin && v->openmin) {
686 if (i->max > v->max) {
688 i->openmax = v->openmax;
690 } else if (i->max == v->max && !i->openmax && v->openmax) {
694 if (!i->integer && v->integer) {
707 } else if (!i->openmin && !i->openmax && i->min == i->max)
709 if (snd_interval_checkempty(i)) {
710 snd_interval_none(i);
716 EXPORT_SYMBOL(snd_interval_refine);
718 static int snd_interval_refine_first(struct snd_interval *i)
720 if (snd_BUG_ON(snd_interval_empty(i)))
722 if (snd_interval_single(i))
725 i->openmax = i->openmin;
731 static int snd_interval_refine_last(struct snd_interval *i)
733 if (snd_BUG_ON(snd_interval_empty(i)))
735 if (snd_interval_single(i))
738 i->openmin = i->openmax;
744 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
746 if (a->empty || b->empty) {
747 snd_interval_none(c);
751 c->min = mul(a->min, b->min);
752 c->openmin = (a->openmin || b->openmin);
753 c->max = mul(a->max, b->max);
754 c->openmax = (a->openmax || b->openmax);
755 c->integer = (a->integer && b->integer);
759 * snd_interval_div - refine the interval value with division
766 * Returns non-zero if the value is changed, zero if not changed.
768 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
771 if (a->empty || b->empty) {
772 snd_interval_none(c);
776 c->min = div32(a->min, b->max, &r);
777 c->openmin = (r || a->openmin || b->openmax);
779 c->max = div32(a->max, b->min, &r);
784 c->openmax = (a->openmax || b->openmin);
793 * snd_interval_muldivk - refine the interval value
796 * @k: divisor (as integer)
801 * Returns non-zero if the value is changed, zero if not changed.
803 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
804 unsigned int k, struct snd_interval *c)
807 if (a->empty || b->empty) {
808 snd_interval_none(c);
812 c->min = muldiv32(a->min, b->min, k, &r);
813 c->openmin = (r || a->openmin || b->openmin);
814 c->max = muldiv32(a->max, b->max, k, &r);
819 c->openmax = (a->openmax || b->openmax);
824 * snd_interval_mulkdiv - refine the interval value
826 * @k: dividend 2 (as integer)
832 * Returns non-zero if the value is changed, zero if not changed.
834 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
835 const struct snd_interval *b, struct snd_interval *c)
838 if (a->empty || b->empty) {
839 snd_interval_none(c);
843 c->min = muldiv32(a->min, k, b->max, &r);
844 c->openmin = (r || a->openmin || b->openmax);
846 c->max = muldiv32(a->max, k, b->min, &r);
851 c->openmax = (a->openmax || b->openmin);
863 * snd_interval_ratnum - refine the interval value
864 * @i: interval to refine
865 * @rats_count: number of ratnum_t
866 * @rats: ratnum_t array
867 * @nump: pointer to store the resultant numerator
868 * @denp: pointer to store the resultant denominator
870 * Return: Positive if the value is changed, zero if it's not changed, or a
871 * negative error code.
873 int snd_interval_ratnum(struct snd_interval *i,
874 unsigned int rats_count, struct snd_ratnum *rats,
875 unsigned int *nump, unsigned int *denp)
877 unsigned int best_num, best_den;
880 struct snd_interval t;
882 unsigned int result_num, result_den;
885 best_num = best_den = best_diff = 0;
886 for (k = 0; k < rats_count; ++k) {
887 unsigned int num = rats[k].num;
889 unsigned int q = i->min;
893 den = div_up(num, q);
894 if (den < rats[k].den_min)
896 if (den > rats[k].den_max)
897 den = rats[k].den_max;
900 r = (den - rats[k].den_min) % rats[k].den_step;
904 diff = num - q * den;
908 diff * best_den < best_diff * den) {
918 t.min = div_down(best_num, best_den);
919 t.openmin = !!(best_num % best_den);
921 result_num = best_num;
922 result_diff = best_diff;
923 result_den = best_den;
924 best_num = best_den = best_diff = 0;
925 for (k = 0; k < rats_count; ++k) {
926 unsigned int num = rats[k].num;
928 unsigned int q = i->max;
934 den = div_down(num, q);
935 if (den > rats[k].den_max)
937 if (den < rats[k].den_min)
938 den = rats[k].den_min;
941 r = (den - rats[k].den_min) % rats[k].den_step;
943 den += rats[k].den_step - r;
945 diff = q * den - num;
949 diff * best_den < best_diff * den) {
959 t.max = div_up(best_num, best_den);
960 t.openmax = !!(best_num % best_den);
962 err = snd_interval_refine(i, &t);
966 if (snd_interval_single(i)) {
967 if (best_diff * result_den < result_diff * best_den) {
968 result_num = best_num;
969 result_den = best_den;
979 EXPORT_SYMBOL(snd_interval_ratnum);
982 * snd_interval_ratden - refine the interval value
983 * @i: interval to refine
984 * @rats_count: number of struct ratden
985 * @rats: struct ratden array
986 * @nump: pointer to store the resultant numerator
987 * @denp: pointer to store the resultant denominator
989 * Return: Positive if the value is changed, zero if it's not changed, or a
990 * negative error code.
992 static int snd_interval_ratden(struct snd_interval *i,
993 unsigned int rats_count, struct snd_ratden *rats,
994 unsigned int *nump, unsigned int *denp)
996 unsigned int best_num, best_diff, best_den;
998 struct snd_interval t;
1001 best_num = best_den = best_diff = 0;
1002 for (k = 0; k < rats_count; ++k) {
1004 unsigned int den = rats[k].den;
1005 unsigned int q = i->min;
1008 if (num > rats[k].num_max)
1010 if (num < rats[k].num_min)
1011 num = rats[k].num_max;
1014 r = (num - rats[k].num_min) % rats[k].num_step;
1016 num += rats[k].num_step - r;
1018 diff = num - q * den;
1019 if (best_num == 0 ||
1020 diff * best_den < best_diff * den) {
1026 if (best_den == 0) {
1030 t.min = div_down(best_num, best_den);
1031 t.openmin = !!(best_num % best_den);
1033 best_num = best_den = best_diff = 0;
1034 for (k = 0; k < rats_count; ++k) {
1036 unsigned int den = rats[k].den;
1037 unsigned int q = i->max;
1040 if (num < rats[k].num_min)
1042 if (num > rats[k].num_max)
1043 num = rats[k].num_max;
1046 r = (num - rats[k].num_min) % rats[k].num_step;
1050 diff = q * den - num;
1051 if (best_num == 0 ||
1052 diff * best_den < best_diff * den) {
1058 if (best_den == 0) {
1062 t.max = div_up(best_num, best_den);
1063 t.openmax = !!(best_num % best_den);
1065 err = snd_interval_refine(i, &t);
1069 if (snd_interval_single(i)) {
1079 * snd_interval_list - refine the interval value from the list
1080 * @i: the interval value to refine
1081 * @count: the number of elements in the list
1082 * @list: the value list
1083 * @mask: the bit-mask to evaluate
1085 * Refines the interval value from the list.
1086 * When mask is non-zero, only the elements corresponding to bit 1 are
1089 * Return: Positive if the value is changed, zero if it's not changed, or a
1090 * negative error code.
1092 int snd_interval_list(struct snd_interval *i, unsigned int count,
1093 const unsigned int *list, unsigned int mask)
1096 struct snd_interval list_range;
1102 snd_interval_any(&list_range);
1103 list_range.min = UINT_MAX;
1105 for (k = 0; k < count; k++) {
1106 if (mask && !(mask & (1 << k)))
1108 if (!snd_interval_test(i, list[k]))
1110 list_range.min = min(list_range.min, list[k]);
1111 list_range.max = max(list_range.max, list[k]);
1113 return snd_interval_refine(i, &list_range);
1116 EXPORT_SYMBOL(snd_interval_list);
1118 static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
1122 n = (i->min - min) % step;
1123 if (n != 0 || i->openmin) {
1127 n = (i->max - min) % step;
1128 if (n != 0 || i->openmax) {
1132 if (snd_interval_checkempty(i)) {
1139 /* Info constraints helpers */
1142 * snd_pcm_hw_rule_add - add the hw-constraint rule
1143 * @runtime: the pcm runtime instance
1144 * @cond: condition bits
1145 * @var: the variable to evaluate
1146 * @func: the evaluation function
1147 * @private: the private data pointer passed to function
1148 * @dep: the dependent variables
1150 * Return: Zero if successful, or a negative error code on failure.
1152 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1154 snd_pcm_hw_rule_func_t func, void *private,
1157 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1158 struct snd_pcm_hw_rule *c;
1161 va_start(args, dep);
1162 if (constrs->rules_num >= constrs->rules_all) {
1163 struct snd_pcm_hw_rule *new;
1164 unsigned int new_rules = constrs->rules_all + 16;
1165 new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1170 if (constrs->rules) {
1171 memcpy(new, constrs->rules,
1172 constrs->rules_num * sizeof(*c));
1173 kfree(constrs->rules);
1175 constrs->rules = new;
1176 constrs->rules_all = new_rules;
1178 c = &constrs->rules[constrs->rules_num];
1182 c->private = private;
1185 if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1192 dep = va_arg(args, int);
1194 constrs->rules_num++;
1199 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1202 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1203 * @runtime: PCM runtime instance
1204 * @var: hw_params variable to apply the mask
1205 * @mask: the bitmap mask
1207 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1209 * Return: Zero if successful, or a negative error code on failure.
1211 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1214 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1215 struct snd_mask *maskp = constrs_mask(constrs, var);
1216 *maskp->bits &= mask;
1217 memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1218 if (*maskp->bits == 0)
1224 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1225 * @runtime: PCM runtime instance
1226 * @var: hw_params variable to apply the mask
1227 * @mask: the 64bit bitmap mask
1229 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1231 * Return: Zero if successful, or a negative error code on failure.
1233 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1236 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1237 struct snd_mask *maskp = constrs_mask(constrs, var);
1238 maskp->bits[0] &= (u_int32_t)mask;
1239 maskp->bits[1] &= (u_int32_t)(mask >> 32);
1240 memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1241 if (! maskp->bits[0] && ! maskp->bits[1])
1247 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1248 * @runtime: PCM runtime instance
1249 * @var: hw_params variable to apply the integer constraint
1251 * Apply the constraint of integer to an interval parameter.
1253 * Return: Positive if the value is changed, zero if it's not changed, or a
1254 * negative error code.
1256 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1258 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1259 return snd_interval_setinteger(constrs_interval(constrs, var));
1262 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1265 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1266 * @runtime: PCM runtime instance
1267 * @var: hw_params variable to apply the range
1268 * @min: the minimal value
1269 * @max: the maximal value
1271 * Apply the min/max range constraint to an interval parameter.
1273 * Return: Positive if the value is changed, zero if it's not changed, or a
1274 * negative error code.
1276 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1277 unsigned int min, unsigned int max)
1279 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1280 struct snd_interval t;
1283 t.openmin = t.openmax = 0;
1285 return snd_interval_refine(constrs_interval(constrs, var), &t);
1288 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1290 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1291 struct snd_pcm_hw_rule *rule)
1293 struct snd_pcm_hw_constraint_list *list = rule->private;
1294 return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1299 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1300 * @runtime: PCM runtime instance
1301 * @cond: condition bits
1302 * @var: hw_params variable to apply the list constraint
1305 * Apply the list of constraints to an interval parameter.
1307 * Return: Zero if successful, or a negative error code on failure.
1309 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1311 snd_pcm_hw_param_t var,
1312 const struct snd_pcm_hw_constraint_list *l)
1314 return snd_pcm_hw_rule_add(runtime, cond, var,
1315 snd_pcm_hw_rule_list, (void *)l,
1319 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1321 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1322 struct snd_pcm_hw_rule *rule)
1324 struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1325 unsigned int num = 0, den = 0;
1327 err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1328 r->nrats, r->rats, &num, &den);
1329 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1330 params->rate_num = num;
1331 params->rate_den = den;
1337 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1338 * @runtime: PCM runtime instance
1339 * @cond: condition bits
1340 * @var: hw_params variable to apply the ratnums constraint
1341 * @r: struct snd_ratnums constriants
1343 * Return: Zero if successful, or a negative error code on failure.
1345 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1347 snd_pcm_hw_param_t var,
1348 struct snd_pcm_hw_constraint_ratnums *r)
1350 return snd_pcm_hw_rule_add(runtime, cond, var,
1351 snd_pcm_hw_rule_ratnums, r,
1355 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1357 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1358 struct snd_pcm_hw_rule *rule)
1360 struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1361 unsigned int num = 0, den = 0;
1362 int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1363 r->nrats, r->rats, &num, &den);
1364 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1365 params->rate_num = num;
1366 params->rate_den = den;
1372 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1373 * @runtime: PCM runtime instance
1374 * @cond: condition bits
1375 * @var: hw_params variable to apply the ratdens constraint
1376 * @r: struct snd_ratdens constriants
1378 * Return: Zero if successful, or a negative error code on failure.
1380 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1382 snd_pcm_hw_param_t var,
1383 struct snd_pcm_hw_constraint_ratdens *r)
1385 return snd_pcm_hw_rule_add(runtime, cond, var,
1386 snd_pcm_hw_rule_ratdens, r,
1390 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1392 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1393 struct snd_pcm_hw_rule *rule)
1395 unsigned int l = (unsigned long) rule->private;
1396 int width = l & 0xffff;
1397 unsigned int msbits = l >> 16;
1398 struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1399 if (snd_interval_single(i) && snd_interval_value(i) == width)
1400 params->msbits = msbits;
1405 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1406 * @runtime: PCM runtime instance
1407 * @cond: condition bits
1408 * @width: sample bits width
1409 * @msbits: msbits width
1411 * Return: Zero if successful, or a negative error code on failure.
1413 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1416 unsigned int msbits)
1418 unsigned long l = (msbits << 16) | width;
1419 return snd_pcm_hw_rule_add(runtime, cond, -1,
1420 snd_pcm_hw_rule_msbits,
1422 SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1425 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1427 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1428 struct snd_pcm_hw_rule *rule)
1430 unsigned long step = (unsigned long) rule->private;
1431 return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1435 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1436 * @runtime: PCM runtime instance
1437 * @cond: condition bits
1438 * @var: hw_params variable to apply the step constraint
1441 * Return: Zero if successful, or a negative error code on failure.
1443 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1445 snd_pcm_hw_param_t var,
1448 return snd_pcm_hw_rule_add(runtime, cond, var,
1449 snd_pcm_hw_rule_step, (void *) step,
1453 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1455 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1457 static unsigned int pow2_sizes[] = {
1458 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1459 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1460 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1461 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1463 return snd_interval_list(hw_param_interval(params, rule->var),
1464 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1468 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1469 * @runtime: PCM runtime instance
1470 * @cond: condition bits
1471 * @var: hw_params variable to apply the power-of-2 constraint
1473 * Return: Zero if successful, or a negative error code on failure.
1475 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1477 snd_pcm_hw_param_t var)
1479 return snd_pcm_hw_rule_add(runtime, cond, var,
1480 snd_pcm_hw_rule_pow2, NULL,
1484 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1486 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1487 struct snd_pcm_hw_rule *rule)
1489 unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1490 struct snd_interval *rate;
1492 rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1493 return snd_interval_list(rate, 1, &base_rate, 0);
1497 * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1498 * @runtime: PCM runtime instance
1499 * @base_rate: the rate at which the hardware does not resample
1501 * Return: Zero if successful, or a negative error code on failure.
1503 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1504 unsigned int base_rate)
1506 return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1507 SNDRV_PCM_HW_PARAM_RATE,
1508 snd_pcm_hw_rule_noresample_func,
1509 (void *)(uintptr_t)base_rate,
1510 SNDRV_PCM_HW_PARAM_RATE, -1);
1512 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1514 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1515 snd_pcm_hw_param_t var)
1517 if (hw_is_mask(var)) {
1518 snd_mask_any(hw_param_mask(params, var));
1519 params->cmask |= 1 << var;
1520 params->rmask |= 1 << var;
1523 if (hw_is_interval(var)) {
1524 snd_interval_any(hw_param_interval(params, var));
1525 params->cmask |= 1 << var;
1526 params->rmask |= 1 << var;
1532 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1535 memset(params, 0, sizeof(*params));
1536 for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1537 _snd_pcm_hw_param_any(params, k);
1538 for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1539 _snd_pcm_hw_param_any(params, k);
1543 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1546 * snd_pcm_hw_param_value - return @params field @var value
1547 * @params: the hw_params instance
1548 * @var: parameter to retrieve
1549 * @dir: pointer to the direction (-1,0,1) or %NULL
1551 * Return: The value for field @var if it's fixed in configuration space
1552 * defined by @params. -%EINVAL otherwise.
1554 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1555 snd_pcm_hw_param_t var, int *dir)
1557 if (hw_is_mask(var)) {
1558 const struct snd_mask *mask = hw_param_mask_c(params, var);
1559 if (!snd_mask_single(mask))
1563 return snd_mask_value(mask);
1565 if (hw_is_interval(var)) {
1566 const struct snd_interval *i = hw_param_interval_c(params, var);
1567 if (!snd_interval_single(i))
1571 return snd_interval_value(i);
1576 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1578 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1579 snd_pcm_hw_param_t var)
1581 if (hw_is_mask(var)) {
1582 snd_mask_none(hw_param_mask(params, var));
1583 params->cmask |= 1 << var;
1584 params->rmask |= 1 << var;
1585 } else if (hw_is_interval(var)) {
1586 snd_interval_none(hw_param_interval(params, var));
1587 params->cmask |= 1 << var;
1588 params->rmask |= 1 << var;
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);
1635 if (snd_BUG_ON(err < 0))
1638 return snd_pcm_hw_param_value(params, var, dir);
1641 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1643 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1644 snd_pcm_hw_param_t var)
1647 if (hw_is_mask(var))
1648 changed = snd_mask_refine_last(hw_param_mask(params, var));
1649 else if (hw_is_interval(var))
1650 changed = snd_interval_refine_last(hw_param_interval(params, var));
1654 params->cmask |= 1 << var;
1655 params->rmask |= 1 << var;
1662 * snd_pcm_hw_param_last - refine config space and return maximum value
1663 * @pcm: PCM instance
1664 * @params: the hw_params instance
1665 * @var: parameter to retrieve
1666 * @dir: pointer to the direction (-1,0,1) or %NULL
1668 * Inside configuration space defined by @params remove from @var all
1669 * values < maximum. Reduce configuration space accordingly.
1671 * Return: The maximum, or a negative error code on failure.
1673 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1674 struct snd_pcm_hw_params *params,
1675 snd_pcm_hw_param_t var, int *dir)
1677 int changed = _snd_pcm_hw_param_last(params, var);
1680 if (params->rmask) {
1681 int err = snd_pcm_hw_refine(pcm, params);
1682 if (snd_BUG_ON(err < 0))
1685 return snd_pcm_hw_param_value(params, var, dir);
1688 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1691 * snd_pcm_hw_param_choose - choose a configuration defined by @params
1692 * @pcm: PCM instance
1693 * @params: the hw_params instance
1695 * Choose one configuration from configuration space defined by @params.
1696 * The configuration chosen is that obtained fixing in this order:
1697 * first access, first format, first subformat, min channels,
1698 * min rate, min period time, max buffer size, min tick time
1700 * Return: Zero if successful, or a negative error code on failure.
1702 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1703 struct snd_pcm_hw_params *params)
1705 static int vars[] = {
1706 SNDRV_PCM_HW_PARAM_ACCESS,
1707 SNDRV_PCM_HW_PARAM_FORMAT,
1708 SNDRV_PCM_HW_PARAM_SUBFORMAT,
1709 SNDRV_PCM_HW_PARAM_CHANNELS,
1710 SNDRV_PCM_HW_PARAM_RATE,
1711 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1712 SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1713 SNDRV_PCM_HW_PARAM_TICK_TIME,
1718 for (v = vars; *v != -1; v++) {
1719 if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1720 err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1722 err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1723 if (snd_BUG_ON(err < 0))
1729 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1732 struct snd_pcm_runtime *runtime = substream->runtime;
1733 unsigned long flags;
1734 snd_pcm_stream_lock_irqsave(substream, flags);
1735 if (snd_pcm_running(substream) &&
1736 snd_pcm_update_hw_ptr(substream) >= 0)
1737 runtime->status->hw_ptr %= runtime->buffer_size;
1739 runtime->status->hw_ptr = 0;
1740 runtime->hw_ptr_wrap = 0;
1742 snd_pcm_stream_unlock_irqrestore(substream, flags);
1746 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1749 struct snd_pcm_channel_info *info = arg;
1750 struct snd_pcm_runtime *runtime = substream->runtime;
1752 if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1756 width = snd_pcm_format_physical_width(runtime->format);
1760 switch (runtime->access) {
1761 case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1762 case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1763 info->first = info->channel * width;
1764 info->step = runtime->channels * width;
1766 case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1767 case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1769 size_t size = runtime->dma_bytes / runtime->channels;
1770 info->first = info->channel * size * 8;
1781 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1784 struct snd_pcm_hw_params *params = arg;
1785 snd_pcm_format_t format;
1786 int channels, width;
1788 params->fifo_size = substream->runtime->hw.fifo_size;
1789 if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1790 format = params_format(params);
1791 channels = params_channels(params);
1792 width = snd_pcm_format_physical_width(format);
1793 params->fifo_size /= width * channels;
1799 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1800 * @substream: the pcm substream instance
1801 * @cmd: ioctl command
1802 * @arg: ioctl argument
1804 * Processes the generic ioctl commands for PCM.
1805 * Can be passed as the ioctl callback for PCM ops.
1807 * Return: Zero if successful, or a negative error code on failure.
1809 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1810 unsigned int cmd, void *arg)
1813 case SNDRV_PCM_IOCTL1_INFO:
1815 case SNDRV_PCM_IOCTL1_RESET:
1816 return snd_pcm_lib_ioctl_reset(substream, arg);
1817 case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1818 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1819 case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1820 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1825 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1828 * snd_pcm_period_elapsed - update the pcm status for the next period
1829 * @substream: the pcm substream instance
1831 * This function is called from the interrupt handler when the
1832 * PCM has processed the period size. It will update the current
1833 * pointer, wake up sleepers, etc.
1835 * Even if more than one periods have elapsed since the last call, you
1836 * have to call this only once.
1838 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1840 struct snd_pcm_runtime *runtime;
1841 unsigned long flags;
1843 if (PCM_RUNTIME_CHECK(substream))
1845 runtime = substream->runtime;
1847 if (runtime->transfer_ack_begin)
1848 runtime->transfer_ack_begin(substream);
1850 snd_pcm_stream_lock_irqsave(substream, flags);
1851 if (!snd_pcm_running(substream) ||
1852 snd_pcm_update_hw_ptr0(substream, 1) < 0)
1855 if (substream->timer_running)
1856 snd_timer_interrupt(substream->timer, 1);
1858 snd_pcm_stream_unlock_irqrestore(substream, flags);
1859 if (runtime->transfer_ack_end)
1860 runtime->transfer_ack_end(substream);
1861 kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1864 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1867 * Wait until avail_min data becomes available
1868 * Returns a negative error code if any error occurs during operation.
1869 * The available space is stored on availp. When err = 0 and avail = 0
1870 * on the capture stream, it indicates the stream is in DRAINING state.
1872 static int wait_for_avail(struct snd_pcm_substream *substream,
1873 snd_pcm_uframes_t *availp)
1875 struct snd_pcm_runtime *runtime = substream->runtime;
1876 int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1879 snd_pcm_uframes_t avail = 0;
1880 long wait_time, tout;
1882 init_waitqueue_entry(&wait, current);
1883 set_current_state(TASK_INTERRUPTIBLE);
1884 add_wait_queue(&runtime->tsleep, &wait);
1886 if (runtime->no_period_wakeup)
1887 wait_time = MAX_SCHEDULE_TIMEOUT;
1890 if (runtime->rate) {
1891 long t = runtime->period_size * 2 / runtime->rate;
1892 wait_time = max(t, wait_time);
1894 wait_time = msecs_to_jiffies(wait_time * 1000);
1898 if (signal_pending(current)) {
1904 * We need to check if space became available already
1905 * (and thus the wakeup happened already) first to close
1906 * the race of space already having become available.
1907 * This check must happen after been added to the waitqueue
1908 * and having current state be INTERRUPTIBLE.
1911 avail = snd_pcm_playback_avail(runtime);
1913 avail = snd_pcm_capture_avail(runtime);
1914 if (avail >= runtime->twake)
1916 snd_pcm_stream_unlock_irq(substream);
1918 tout = schedule_timeout(wait_time);
1920 snd_pcm_stream_lock_irq(substream);
1921 set_current_state(TASK_INTERRUPTIBLE);
1922 switch (runtime->status->state) {
1923 case SNDRV_PCM_STATE_SUSPENDED:
1926 case SNDRV_PCM_STATE_XRUN:
1929 case SNDRV_PCM_STATE_DRAINING:
1933 avail = 0; /* indicate draining */
1935 case SNDRV_PCM_STATE_OPEN:
1936 case SNDRV_PCM_STATE_SETUP:
1937 case SNDRV_PCM_STATE_DISCONNECTED:
1940 case SNDRV_PCM_STATE_PAUSED:
1944 snd_printd("%s write error (DMA or IRQ trouble?)\n",
1945 is_playback ? "playback" : "capture");
1951 set_current_state(TASK_RUNNING);
1952 remove_wait_queue(&runtime->tsleep, &wait);
1957 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1959 unsigned long data, unsigned int off,
1960 snd_pcm_uframes_t frames)
1962 struct snd_pcm_runtime *runtime = substream->runtime;
1964 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1965 if (substream->ops->copy) {
1966 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1969 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1970 if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1976 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1977 unsigned long data, unsigned int off,
1978 snd_pcm_uframes_t size);
1980 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1982 snd_pcm_uframes_t size,
1984 transfer_f transfer)
1986 struct snd_pcm_runtime *runtime = substream->runtime;
1987 snd_pcm_uframes_t xfer = 0;
1988 snd_pcm_uframes_t offset = 0;
1989 snd_pcm_uframes_t avail;
1995 snd_pcm_stream_lock_irq(substream);
1996 switch (runtime->status->state) {
1997 case SNDRV_PCM_STATE_PREPARED:
1998 case SNDRV_PCM_STATE_RUNNING:
1999 case SNDRV_PCM_STATE_PAUSED:
2001 case SNDRV_PCM_STATE_XRUN:
2004 case SNDRV_PCM_STATE_SUSPENDED:
2012 runtime->twake = runtime->control->avail_min ? : 1;
2013 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2014 snd_pcm_update_hw_ptr(substream);
2015 avail = snd_pcm_playback_avail(runtime);
2017 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2018 snd_pcm_uframes_t cont;
2024 runtime->twake = min_t(snd_pcm_uframes_t, size,
2025 runtime->control->avail_min ? : 1);
2026 err = wait_for_avail(substream, &avail);
2030 frames = size > avail ? avail : size;
2031 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2034 if (snd_BUG_ON(!frames)) {
2036 snd_pcm_stream_unlock_irq(substream);
2039 appl_ptr = runtime->control->appl_ptr;
2040 appl_ofs = appl_ptr % runtime->buffer_size;
2041 snd_pcm_stream_unlock_irq(substream);
2042 err = transfer(substream, appl_ofs, data, offset, frames);
2043 snd_pcm_stream_lock_irq(substream);
2046 switch (runtime->status->state) {
2047 case SNDRV_PCM_STATE_XRUN:
2050 case SNDRV_PCM_STATE_SUSPENDED:
2057 if (appl_ptr >= runtime->boundary)
2058 appl_ptr -= runtime->boundary;
2059 runtime->control->appl_ptr = appl_ptr;
2060 if (substream->ops->ack)
2061 substream->ops->ack(substream);
2067 if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2068 snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2069 err = snd_pcm_start(substream);
2076 if (xfer > 0 && err >= 0)
2077 snd_pcm_update_state(substream, runtime);
2078 snd_pcm_stream_unlock_irq(substream);
2079 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2082 /* sanity-check for read/write methods */
2083 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2085 struct snd_pcm_runtime *runtime;
2086 if (PCM_RUNTIME_CHECK(substream))
2088 runtime = substream->runtime;
2089 if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
2091 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2096 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
2098 struct snd_pcm_runtime *runtime;
2102 err = pcm_sanity_check(substream);
2105 runtime = substream->runtime;
2106 nonblock = !!(substream->f_flags & O_NONBLOCK);
2108 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2109 runtime->channels > 1)
2111 return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
2112 snd_pcm_lib_write_transfer);
2115 EXPORT_SYMBOL(snd_pcm_lib_write);
2117 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
2119 unsigned long data, unsigned int off,
2120 snd_pcm_uframes_t frames)
2122 struct snd_pcm_runtime *runtime = substream->runtime;
2124 void __user **bufs = (void __user **)data;
2125 int channels = runtime->channels;
2127 if (substream->ops->copy) {
2128 if (snd_BUG_ON(!substream->ops->silence))
2130 for (c = 0; c < channels; ++c, ++bufs) {
2131 if (*bufs == NULL) {
2132 if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
2135 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2136 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2141 /* default transfer behaviour */
2142 size_t dma_csize = runtime->dma_bytes / channels;
2143 for (c = 0; c < channels; ++c, ++bufs) {
2144 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2145 if (*bufs == NULL) {
2146 snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
2148 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2149 if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
2157 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
2159 snd_pcm_uframes_t frames)
2161 struct snd_pcm_runtime *runtime;
2165 err = pcm_sanity_check(substream);
2168 runtime = substream->runtime;
2169 nonblock = !!(substream->f_flags & O_NONBLOCK);
2171 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2173 return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2174 nonblock, snd_pcm_lib_writev_transfer);
2177 EXPORT_SYMBOL(snd_pcm_lib_writev);
2179 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
2181 unsigned long data, unsigned int off,
2182 snd_pcm_uframes_t frames)
2184 struct snd_pcm_runtime *runtime = substream->runtime;
2186 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2187 if (substream->ops->copy) {
2188 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2191 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2192 if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2198 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2200 snd_pcm_uframes_t size,
2202 transfer_f transfer)
2204 struct snd_pcm_runtime *runtime = substream->runtime;
2205 snd_pcm_uframes_t xfer = 0;
2206 snd_pcm_uframes_t offset = 0;
2207 snd_pcm_uframes_t avail;
2213 snd_pcm_stream_lock_irq(substream);
2214 switch (runtime->status->state) {
2215 case SNDRV_PCM_STATE_PREPARED:
2216 if (size >= runtime->start_threshold) {
2217 err = snd_pcm_start(substream);
2222 case SNDRV_PCM_STATE_DRAINING:
2223 case SNDRV_PCM_STATE_RUNNING:
2224 case SNDRV_PCM_STATE_PAUSED:
2226 case SNDRV_PCM_STATE_XRUN:
2229 case SNDRV_PCM_STATE_SUSPENDED:
2237 runtime->twake = runtime->control->avail_min ? : 1;
2238 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2239 snd_pcm_update_hw_ptr(substream);
2240 avail = snd_pcm_capture_avail(runtime);
2242 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2243 snd_pcm_uframes_t cont;
2245 if (runtime->status->state ==
2246 SNDRV_PCM_STATE_DRAINING) {
2247 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2254 runtime->twake = min_t(snd_pcm_uframes_t, size,
2255 runtime->control->avail_min ? : 1);
2256 err = wait_for_avail(substream, &avail);
2260 continue; /* draining */
2262 frames = size > avail ? avail : size;
2263 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2266 if (snd_BUG_ON(!frames)) {
2268 snd_pcm_stream_unlock_irq(substream);
2271 appl_ptr = runtime->control->appl_ptr;
2272 appl_ofs = appl_ptr % runtime->buffer_size;
2273 snd_pcm_stream_unlock_irq(substream);
2274 err = transfer(substream, appl_ofs, data, offset, frames);
2275 snd_pcm_stream_lock_irq(substream);
2278 switch (runtime->status->state) {
2279 case SNDRV_PCM_STATE_XRUN:
2282 case SNDRV_PCM_STATE_SUSPENDED:
2289 if (appl_ptr >= runtime->boundary)
2290 appl_ptr -= runtime->boundary;
2291 runtime->control->appl_ptr = appl_ptr;
2292 if (substream->ops->ack)
2293 substream->ops->ack(substream);
2302 if (xfer > 0 && err >= 0)
2303 snd_pcm_update_state(substream, runtime);
2304 snd_pcm_stream_unlock_irq(substream);
2305 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2308 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2310 struct snd_pcm_runtime *runtime;
2314 err = pcm_sanity_check(substream);
2317 runtime = substream->runtime;
2318 nonblock = !!(substream->f_flags & O_NONBLOCK);
2319 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2321 return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2324 EXPORT_SYMBOL(snd_pcm_lib_read);
2326 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2328 unsigned long data, unsigned int off,
2329 snd_pcm_uframes_t frames)
2331 struct snd_pcm_runtime *runtime = substream->runtime;
2333 void __user **bufs = (void __user **)data;
2334 int channels = runtime->channels;
2336 if (substream->ops->copy) {
2337 for (c = 0; c < channels; ++c, ++bufs) {
2341 buf = *bufs + samples_to_bytes(runtime, off);
2342 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2346 snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2347 for (c = 0; c < channels; ++c, ++bufs) {
2353 hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2354 buf = *bufs + samples_to_bytes(runtime, off);
2355 if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2362 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2364 snd_pcm_uframes_t frames)
2366 struct snd_pcm_runtime *runtime;
2370 err = pcm_sanity_check(substream);
2373 runtime = substream->runtime;
2374 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2377 nonblock = !!(substream->f_flags & O_NONBLOCK);
2378 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2380 return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2383 EXPORT_SYMBOL(snd_pcm_lib_readv);
2386 * standard channel mapping helpers
2389 /* default channel maps for multi-channel playbacks, up to 8 channels */
2390 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2392 .map = { SNDRV_CHMAP_MONO } },
2394 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2396 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2397 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2399 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2400 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2401 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2403 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2404 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2405 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2406 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2409 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2411 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2412 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2414 .map = { SNDRV_CHMAP_MONO } },
2416 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2418 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2419 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2421 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2422 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2423 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2425 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2426 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2427 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2428 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2431 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2433 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2435 if (ch > info->max_channels)
2437 return !info->channel_mask || (info->channel_mask & (1U << ch));
2440 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2441 struct snd_ctl_elem_info *uinfo)
2443 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2445 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2447 uinfo->count = info->max_channels;
2448 uinfo->value.integer.min = 0;
2449 uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2453 /* get callback for channel map ctl element
2454 * stores the channel position firstly matching with the current channels
2456 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2457 struct snd_ctl_elem_value *ucontrol)
2459 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2460 unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2461 struct snd_pcm_substream *substream;
2462 const struct snd_pcm_chmap_elem *map;
2464 if (snd_BUG_ON(!info->chmap))
2466 substream = snd_pcm_chmap_substream(info, idx);
2469 memset(ucontrol->value.integer.value, 0,
2470 sizeof(ucontrol->value.integer.value));
2471 if (!substream->runtime)
2472 return 0; /* no channels set */
2473 for (map = info->chmap; map->channels; map++) {
2475 if (map->channels == substream->runtime->channels &&
2476 valid_chmap_channels(info, map->channels)) {
2477 for (i = 0; i < map->channels; i++)
2478 ucontrol->value.integer.value[i] = map->map[i];
2485 /* tlv callback for channel map ctl element
2486 * expands the pre-defined channel maps in a form of TLV
2488 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2489 unsigned int size, unsigned int __user *tlv)
2491 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2492 const struct snd_pcm_chmap_elem *map;
2493 unsigned int __user *dst;
2496 if (snd_BUG_ON(!info->chmap))
2500 if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2504 for (map = info->chmap; map->channels; map++) {
2505 int chs_bytes = map->channels * 4;
2506 if (!valid_chmap_channels(info, map->channels))
2510 if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2511 put_user(chs_bytes, dst + 1))
2516 if (size < chs_bytes)
2520 for (c = 0; c < map->channels; c++) {
2521 if (put_user(map->map[c], dst))
2526 if (put_user(count, tlv + 1))
2531 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2533 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2534 info->pcm->streams[info->stream].chmap_kctl = NULL;
2539 * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2540 * @pcm: the assigned PCM instance
2541 * @stream: stream direction
2542 * @chmap: channel map elements (for query)
2543 * @max_channels: the max number of channels for the stream
2544 * @private_value: the value passed to each kcontrol's private_value field
2545 * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2547 * Create channel-mapping control elements assigned to the given PCM stream(s).
2548 * Return: Zero if successful, or a negative error value.
2550 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2551 const struct snd_pcm_chmap_elem *chmap,
2553 unsigned long private_value,
2554 struct snd_pcm_chmap **info_ret)
2556 struct snd_pcm_chmap *info;
2557 struct snd_kcontrol_new knew = {
2558 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
2559 .access = SNDRV_CTL_ELEM_ACCESS_READ |
2560 SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2561 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2562 .info = pcm_chmap_ctl_info,
2563 .get = pcm_chmap_ctl_get,
2564 .tlv.c = pcm_chmap_ctl_tlv,
2568 info = kzalloc(sizeof(*info), GFP_KERNEL);
2572 info->stream = stream;
2573 info->chmap = chmap;
2574 info->max_channels = max_channels;
2575 if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2576 knew.name = "Playback Channel Map";
2578 knew.name = "Capture Channel Map";
2579 knew.device = pcm->device;
2580 knew.count = pcm->streams[stream].substream_count;
2581 knew.private_value = private_value;
2582 info->kctl = snd_ctl_new1(&knew, info);
2587 info->kctl->private_free = pcm_chmap_ctl_private_free;
2588 err = snd_ctl_add(pcm->card, info->kctl);
2591 pcm->streams[stream].chmap_kctl = info->kctl;
2596 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);