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 pcm_warn(substream->pcm, "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 pr_err_ratelimited("ALSA: PCM: " fmt, ##args); \
188 dump_stack_on_xrun(substream); \
192 #define XRUN_LOG_CNT 10
194 struct hwptr_log_entry {
195 unsigned int in_interrupt;
196 unsigned long jiffies;
197 snd_pcm_uframes_t pos;
198 snd_pcm_uframes_t period_size;
199 snd_pcm_uframes_t buffer_size;
200 snd_pcm_uframes_t old_hw_ptr;
201 snd_pcm_uframes_t hw_ptr_base;
204 struct snd_pcm_hwptr_log {
207 struct hwptr_log_entry entries[XRUN_LOG_CNT];
210 static void xrun_log(struct snd_pcm_substream *substream,
211 snd_pcm_uframes_t pos, int in_interrupt)
213 struct snd_pcm_runtime *runtime = substream->runtime;
214 struct snd_pcm_hwptr_log *log = runtime->hwptr_log;
215 struct hwptr_log_entry *entry;
218 log = kzalloc(sizeof(*log), GFP_ATOMIC);
221 runtime->hwptr_log = log;
223 if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
226 entry = &log->entries[log->idx];
227 entry->in_interrupt = in_interrupt;
228 entry->jiffies = jiffies;
230 entry->period_size = runtime->period_size;
231 entry->buffer_size = runtime->buffer_size;
232 entry->old_hw_ptr = runtime->status->hw_ptr;
233 entry->hw_ptr_base = runtime->hw_ptr_base;
234 log->idx = (log->idx + 1) % XRUN_LOG_CNT;
237 static void xrun_log_show(struct snd_pcm_substream *substream)
239 struct snd_pcm_hwptr_log *log = substream->runtime->hwptr_log;
240 struct hwptr_log_entry *entry;
247 if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
249 snd_pcm_debug_name(substream, name, sizeof(name));
250 for (cnt = 0, idx = log->idx; cnt < XRUN_LOG_CNT; cnt++) {
251 entry = &log->entries[idx];
252 if (entry->period_size == 0)
254 pr_info("hwptr log: %s: %sj=%lu, pos=%ld/%ld/%ld, "
256 name, entry->in_interrupt ? "[Q] " : "",
258 (unsigned long)entry->pos,
259 (unsigned long)entry->period_size,
260 (unsigned long)entry->buffer_size,
261 (unsigned long)entry->old_hw_ptr,
262 (unsigned long)entry->hw_ptr_base);
269 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
271 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
272 #define xrun_log(substream, pos, in_interrupt) do { } while (0)
273 #define xrun_log_show(substream) do { } while (0)
277 int snd_pcm_update_state(struct snd_pcm_substream *substream,
278 struct snd_pcm_runtime *runtime)
280 snd_pcm_uframes_t avail;
282 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
283 avail = snd_pcm_playback_avail(runtime);
285 avail = snd_pcm_capture_avail(runtime);
286 if (avail > runtime->avail_max)
287 runtime->avail_max = avail;
288 if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
289 if (avail >= runtime->buffer_size) {
290 snd_pcm_drain_done(substream);
294 if (avail >= runtime->stop_threshold) {
299 if (runtime->twake) {
300 if (avail >= runtime->twake)
301 wake_up(&runtime->tsleep);
302 } else if (avail >= runtime->control->avail_min)
303 wake_up(&runtime->sleep);
307 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
308 unsigned int in_interrupt)
310 struct snd_pcm_runtime *runtime = substream->runtime;
311 snd_pcm_uframes_t pos;
312 snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
313 snd_pcm_sframes_t hdelta, delta;
314 unsigned long jdelta;
315 unsigned long curr_jiffies;
316 struct timespec curr_tstamp;
317 struct timespec audio_tstamp;
318 int crossed_boundary = 0;
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 ((runtime->hw.info & SNDRV_PCM_INFO_HAS_WALL_CLOCK) &&
334 (substream->ops->wall_clock))
335 substream->ops->wall_clock(substream, &audio_tstamp);
338 if (pos == SNDRV_PCM_POS_XRUN) {
342 if (pos >= runtime->buffer_size) {
343 if (printk_ratelimit()) {
345 snd_pcm_debug_name(substream, name, sizeof(name));
346 xrun_log_show(substream);
347 pcm_err(substream->pcm,
348 "XRUN: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
349 name, pos, runtime->buffer_size,
350 runtime->period_size);
354 pos -= pos % runtime->min_align;
355 if (xrun_debug(substream, XRUN_DEBUG_LOG))
356 xrun_log(substream, pos, in_interrupt);
357 hw_base = runtime->hw_ptr_base;
358 new_hw_ptr = hw_base + pos;
360 /* we know that one period was processed */
361 /* delta = "expected next hw_ptr" for in_interrupt != 0 */
362 delta = runtime->hw_ptr_interrupt + runtime->period_size;
363 if (delta > new_hw_ptr) {
364 /* check for double acknowledged interrupts */
365 hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
366 if (hdelta > runtime->hw_ptr_buffer_jiffies/2) {
367 hw_base += runtime->buffer_size;
368 if (hw_base >= runtime->boundary) {
372 new_hw_ptr = hw_base + pos;
377 /* new_hw_ptr might be lower than old_hw_ptr in case when */
378 /* pointer crosses the end of the ring buffer */
379 if (new_hw_ptr < old_hw_ptr) {
380 hw_base += runtime->buffer_size;
381 if (hw_base >= runtime->boundary) {
385 new_hw_ptr = hw_base + pos;
388 delta = new_hw_ptr - old_hw_ptr;
390 delta += runtime->boundary;
391 if (xrun_debug(substream, in_interrupt ?
392 XRUN_DEBUG_PERIODUPDATE : XRUN_DEBUG_HWPTRUPDATE)) {
394 snd_pcm_debug_name(substream, name, sizeof(name));
395 pcm_dbg(substream->pcm,
396 "%s_update: %s: pos=%u/%u/%u, hwptr=%ld/%ld/%ld/%ld\n",
397 in_interrupt ? "period" : "hwptr",
400 (unsigned int)runtime->period_size,
401 (unsigned int)runtime->buffer_size,
402 (unsigned long)delta,
403 (unsigned long)old_hw_ptr,
404 (unsigned long)new_hw_ptr,
405 (unsigned long)runtime->hw_ptr_base);
408 if (runtime->no_period_wakeup) {
409 snd_pcm_sframes_t xrun_threshold;
411 * Without regular period interrupts, we have to check
412 * the elapsed time to detect xruns.
414 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
415 if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
417 hdelta = jdelta - delta * HZ / runtime->rate;
418 xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
419 while (hdelta > xrun_threshold) {
420 delta += runtime->buffer_size;
421 hw_base += runtime->buffer_size;
422 if (hw_base >= runtime->boundary) {
426 new_hw_ptr = hw_base + pos;
427 hdelta -= runtime->hw_ptr_buffer_jiffies;
432 /* something must be really wrong */
433 if (delta >= runtime->buffer_size + runtime->period_size) {
434 hw_ptr_error(substream,
435 "Unexpected hw_pointer value %s"
436 "(stream=%i, pos=%ld, new_hw_ptr=%ld, "
438 in_interrupt ? "[Q] " : "[P]",
439 substream->stream, (long)pos,
440 (long)new_hw_ptr, (long)old_hw_ptr);
444 /* Do jiffies check only in xrun_debug mode */
445 if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
446 goto no_jiffies_check;
448 /* Skip the jiffies check for hardwares with BATCH flag.
449 * Such hardware usually just increases the position at each IRQ,
450 * thus it can't give any strange position.
452 if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
453 goto no_jiffies_check;
455 if (hdelta < runtime->delay)
456 goto no_jiffies_check;
457 hdelta -= runtime->delay;
458 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
459 if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
461 (((runtime->period_size * HZ) / runtime->rate)
463 /* move new_hw_ptr according jiffies not pos variable */
464 new_hw_ptr = old_hw_ptr;
466 /* use loop to avoid checks for delta overflows */
467 /* the delta value is small or zero in most cases */
469 new_hw_ptr += runtime->period_size;
470 if (new_hw_ptr >= runtime->boundary) {
471 new_hw_ptr -= runtime->boundary;
476 /* align hw_base to buffer_size */
477 hw_ptr_error(substream,
478 "hw_ptr skipping! %s"
479 "(pos=%ld, delta=%ld, period=%ld, "
480 "jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
481 in_interrupt ? "[Q] " : "",
482 (long)pos, (long)hdelta,
483 (long)runtime->period_size, jdelta,
484 ((hdelta * HZ) / runtime->rate), hw_base,
485 (unsigned long)old_hw_ptr,
486 (unsigned long)new_hw_ptr);
487 /* reset values to proper state */
489 hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
492 if (delta > runtime->period_size + runtime->period_size / 2) {
493 hw_ptr_error(substream,
494 "Lost interrupts? %s"
495 "(stream=%i, delta=%ld, new_hw_ptr=%ld, "
497 in_interrupt ? "[Q] " : "",
498 substream->stream, (long)delta,
504 if (runtime->status->hw_ptr == new_hw_ptr)
507 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
508 runtime->silence_size > 0)
509 snd_pcm_playback_silence(substream, new_hw_ptr);
512 delta = new_hw_ptr - runtime->hw_ptr_interrupt;
514 delta += runtime->boundary;
515 delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
516 runtime->hw_ptr_interrupt += delta;
517 if (runtime->hw_ptr_interrupt >= runtime->boundary)
518 runtime->hw_ptr_interrupt -= runtime->boundary;
520 runtime->hw_ptr_base = hw_base;
521 runtime->status->hw_ptr = new_hw_ptr;
522 runtime->hw_ptr_jiffies = curr_jiffies;
523 if (crossed_boundary) {
524 snd_BUG_ON(crossed_boundary != 1);
525 runtime->hw_ptr_wrap += runtime->boundary;
527 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
528 runtime->status->tstamp = curr_tstamp;
530 if (!(runtime->hw.info & SNDRV_PCM_INFO_HAS_WALL_CLOCK)) {
532 * no wall clock available, provide audio timestamp
533 * derived from pointer position+delay
535 u64 audio_frames, audio_nsecs;
537 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
538 audio_frames = runtime->hw_ptr_wrap
539 + runtime->status->hw_ptr
542 audio_frames = runtime->hw_ptr_wrap
543 + runtime->status->hw_ptr
545 audio_nsecs = div_u64(audio_frames * 1000000000LL,
547 audio_tstamp = ns_to_timespec(audio_nsecs);
549 runtime->status->audio_tstamp = audio_tstamp;
552 return snd_pcm_update_state(substream, runtime);
555 /* CAUTION: call it with irq disabled */
556 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
558 return snd_pcm_update_hw_ptr0(substream, 0);
562 * snd_pcm_set_ops - set the PCM operators
563 * @pcm: the pcm instance
564 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
565 * @ops: the operator table
567 * Sets the given PCM operators to the pcm instance.
569 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
570 const struct snd_pcm_ops *ops)
572 struct snd_pcm_str *stream = &pcm->streams[direction];
573 struct snd_pcm_substream *substream;
575 for (substream = stream->substream; substream != NULL; substream = substream->next)
576 substream->ops = ops;
579 EXPORT_SYMBOL(snd_pcm_set_ops);
582 * snd_pcm_sync - set the PCM sync id
583 * @substream: the pcm substream
585 * Sets the PCM sync identifier for the card.
587 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
589 struct snd_pcm_runtime *runtime = substream->runtime;
591 runtime->sync.id32[0] = substream->pcm->card->number;
592 runtime->sync.id32[1] = -1;
593 runtime->sync.id32[2] = -1;
594 runtime->sync.id32[3] = -1;
597 EXPORT_SYMBOL(snd_pcm_set_sync);
600 * Standard ioctl routine
603 static inline unsigned int div32(unsigned int a, unsigned int b,
614 static inline unsigned int div_down(unsigned int a, unsigned int b)
621 static inline unsigned int div_up(unsigned int a, unsigned int b)
633 static inline unsigned int mul(unsigned int a, unsigned int b)
637 if (div_down(UINT_MAX, a) < b)
642 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
643 unsigned int c, unsigned int *r)
645 u_int64_t n = (u_int64_t) a * b;
651 n = div_u64_rem(n, c, r);
660 * snd_interval_refine - refine the interval value of configurator
661 * @i: the interval value to refine
662 * @v: the interval value to refer to
664 * Refines the interval value with the reference value.
665 * The interval is changed to the range satisfying both intervals.
666 * The interval status (min, max, integer, etc.) are evaluated.
668 * Return: Positive if the value is changed, zero if it's not changed, or a
669 * negative error code.
671 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
674 if (snd_BUG_ON(snd_interval_empty(i)))
676 if (i->min < v->min) {
678 i->openmin = v->openmin;
680 } else if (i->min == v->min && !i->openmin && v->openmin) {
684 if (i->max > v->max) {
686 i->openmax = v->openmax;
688 } else if (i->max == v->max && !i->openmax && v->openmax) {
692 if (!i->integer && v->integer) {
705 } else if (!i->openmin && !i->openmax && i->min == i->max)
707 if (snd_interval_checkempty(i)) {
708 snd_interval_none(i);
714 EXPORT_SYMBOL(snd_interval_refine);
716 static int snd_interval_refine_first(struct snd_interval *i)
718 if (snd_BUG_ON(snd_interval_empty(i)))
720 if (snd_interval_single(i))
723 i->openmax = i->openmin;
729 static int snd_interval_refine_last(struct snd_interval *i)
731 if (snd_BUG_ON(snd_interval_empty(i)))
733 if (snd_interval_single(i))
736 i->openmin = i->openmax;
742 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
744 if (a->empty || b->empty) {
745 snd_interval_none(c);
749 c->min = mul(a->min, b->min);
750 c->openmin = (a->openmin || b->openmin);
751 c->max = mul(a->max, b->max);
752 c->openmax = (a->openmax || b->openmax);
753 c->integer = (a->integer && b->integer);
757 * snd_interval_div - refine the interval value with division
764 * Returns non-zero if the value is changed, zero if not changed.
766 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
769 if (a->empty || b->empty) {
770 snd_interval_none(c);
774 c->min = div32(a->min, b->max, &r);
775 c->openmin = (r || a->openmin || b->openmax);
777 c->max = div32(a->max, b->min, &r);
782 c->openmax = (a->openmax || b->openmin);
791 * snd_interval_muldivk - refine the interval value
794 * @k: divisor (as integer)
799 * Returns non-zero if the value is changed, zero if not changed.
801 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
802 unsigned int k, struct snd_interval *c)
805 if (a->empty || b->empty) {
806 snd_interval_none(c);
810 c->min = muldiv32(a->min, b->min, k, &r);
811 c->openmin = (r || a->openmin || b->openmin);
812 c->max = muldiv32(a->max, b->max, k, &r);
817 c->openmax = (a->openmax || b->openmax);
822 * snd_interval_mulkdiv - refine the interval value
824 * @k: dividend 2 (as integer)
830 * Returns non-zero if the value is changed, zero if not changed.
832 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
833 const struct snd_interval *b, struct snd_interval *c)
836 if (a->empty || b->empty) {
837 snd_interval_none(c);
841 c->min = muldiv32(a->min, k, b->max, &r);
842 c->openmin = (r || a->openmin || b->openmax);
844 c->max = muldiv32(a->max, k, b->min, &r);
849 c->openmax = (a->openmax || b->openmin);
861 * snd_interval_ratnum - refine the interval value
862 * @i: interval to refine
863 * @rats_count: number of ratnum_t
864 * @rats: ratnum_t array
865 * @nump: pointer to store the resultant numerator
866 * @denp: pointer to store the resultant denominator
868 * Return: Positive if the value is changed, zero if it's not changed, or a
869 * negative error code.
871 int snd_interval_ratnum(struct snd_interval *i,
872 unsigned int rats_count, struct snd_ratnum *rats,
873 unsigned int *nump, unsigned int *denp)
875 unsigned int best_num, best_den;
878 struct snd_interval t;
880 unsigned int result_num, result_den;
883 best_num = best_den = best_diff = 0;
884 for (k = 0; k < rats_count; ++k) {
885 unsigned int num = rats[k].num;
887 unsigned int q = i->min;
891 den = div_up(num, q);
892 if (den < rats[k].den_min)
894 if (den > rats[k].den_max)
895 den = rats[k].den_max;
898 r = (den - rats[k].den_min) % rats[k].den_step;
902 diff = num - q * den;
906 diff * best_den < best_diff * den) {
916 t.min = div_down(best_num, best_den);
917 t.openmin = !!(best_num % best_den);
919 result_num = best_num;
920 result_diff = best_diff;
921 result_den = best_den;
922 best_num = best_den = best_diff = 0;
923 for (k = 0; k < rats_count; ++k) {
924 unsigned int num = rats[k].num;
926 unsigned int q = i->max;
932 den = div_down(num, q);
933 if (den > rats[k].den_max)
935 if (den < rats[k].den_min)
936 den = rats[k].den_min;
939 r = (den - rats[k].den_min) % rats[k].den_step;
941 den += rats[k].den_step - r;
943 diff = q * den - num;
947 diff * best_den < best_diff * den) {
957 t.max = div_up(best_num, best_den);
958 t.openmax = !!(best_num % best_den);
960 err = snd_interval_refine(i, &t);
964 if (snd_interval_single(i)) {
965 if (best_diff * result_den < result_diff * best_den) {
966 result_num = best_num;
967 result_den = best_den;
977 EXPORT_SYMBOL(snd_interval_ratnum);
980 * snd_interval_ratden - refine the interval value
981 * @i: interval to refine
982 * @rats_count: number of struct ratden
983 * @rats: struct ratden array
984 * @nump: pointer to store the resultant numerator
985 * @denp: pointer to store the resultant denominator
987 * Return: Positive if the value is changed, zero if it's not changed, or a
988 * negative error code.
990 static int snd_interval_ratden(struct snd_interval *i,
991 unsigned int rats_count, struct snd_ratden *rats,
992 unsigned int *nump, unsigned int *denp)
994 unsigned int best_num, best_diff, best_den;
996 struct snd_interval t;
999 best_num = best_den = best_diff = 0;
1000 for (k = 0; k < rats_count; ++k) {
1002 unsigned int den = rats[k].den;
1003 unsigned int q = i->min;
1006 if (num > rats[k].num_max)
1008 if (num < rats[k].num_min)
1009 num = rats[k].num_max;
1012 r = (num - rats[k].num_min) % rats[k].num_step;
1014 num += rats[k].num_step - r;
1016 diff = num - q * den;
1017 if (best_num == 0 ||
1018 diff * best_den < best_diff * den) {
1024 if (best_den == 0) {
1028 t.min = div_down(best_num, best_den);
1029 t.openmin = !!(best_num % best_den);
1031 best_num = best_den = best_diff = 0;
1032 for (k = 0; k < rats_count; ++k) {
1034 unsigned int den = rats[k].den;
1035 unsigned int q = i->max;
1038 if (num < rats[k].num_min)
1040 if (num > rats[k].num_max)
1041 num = rats[k].num_max;
1044 r = (num - rats[k].num_min) % rats[k].num_step;
1048 diff = q * den - num;
1049 if (best_num == 0 ||
1050 diff * best_den < best_diff * den) {
1056 if (best_den == 0) {
1060 t.max = div_up(best_num, best_den);
1061 t.openmax = !!(best_num % best_den);
1063 err = snd_interval_refine(i, &t);
1067 if (snd_interval_single(i)) {
1077 * snd_interval_list - refine the interval value from the list
1078 * @i: the interval value to refine
1079 * @count: the number of elements in the list
1080 * @list: the value list
1081 * @mask: the bit-mask to evaluate
1083 * Refines the interval value from the list.
1084 * When mask is non-zero, only the elements corresponding to bit 1 are
1087 * Return: Positive if the value is changed, zero if it's not changed, or a
1088 * negative error code.
1090 int snd_interval_list(struct snd_interval *i, unsigned int count,
1091 const unsigned int *list, unsigned int mask)
1094 struct snd_interval list_range;
1100 snd_interval_any(&list_range);
1101 list_range.min = UINT_MAX;
1103 for (k = 0; k < count; k++) {
1104 if (mask && !(mask & (1 << k)))
1106 if (!snd_interval_test(i, list[k]))
1108 list_range.min = min(list_range.min, list[k]);
1109 list_range.max = max(list_range.max, list[k]);
1111 return snd_interval_refine(i, &list_range);
1114 EXPORT_SYMBOL(snd_interval_list);
1116 static int snd_interval_step(struct snd_interval *i, unsigned int step)
1121 if (n != 0 || i->openmin) {
1127 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])
1245 EXPORT_SYMBOL(snd_pcm_hw_constraint_mask64);
1248 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1249 * @runtime: PCM runtime instance
1250 * @var: hw_params variable to apply the integer constraint
1252 * Apply the constraint of integer to an interval parameter.
1254 * Return: Positive if the value is changed, zero if it's not changed, or a
1255 * negative error code.
1257 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1259 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1260 return snd_interval_setinteger(constrs_interval(constrs, var));
1263 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1266 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1267 * @runtime: PCM runtime instance
1268 * @var: hw_params variable to apply the range
1269 * @min: the minimal value
1270 * @max: the maximal value
1272 * Apply the min/max range constraint to an interval parameter.
1274 * Return: Positive if the value is changed, zero if it's not changed, or a
1275 * negative error code.
1277 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1278 unsigned int min, unsigned int max)
1280 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1281 struct snd_interval t;
1284 t.openmin = t.openmax = 0;
1286 return snd_interval_refine(constrs_interval(constrs, var), &t);
1289 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1291 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1292 struct snd_pcm_hw_rule *rule)
1294 struct snd_pcm_hw_constraint_list *list = rule->private;
1295 return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1300 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1301 * @runtime: PCM runtime instance
1302 * @cond: condition bits
1303 * @var: hw_params variable to apply the list constraint
1306 * Apply the list of constraints to an interval parameter.
1308 * Return: Zero if successful, or a negative error code on failure.
1310 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1312 snd_pcm_hw_param_t var,
1313 const struct snd_pcm_hw_constraint_list *l)
1315 return snd_pcm_hw_rule_add(runtime, cond, var,
1316 snd_pcm_hw_rule_list, (void *)l,
1320 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1322 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1323 struct snd_pcm_hw_rule *rule)
1325 struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1326 unsigned int num = 0, den = 0;
1328 err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1329 r->nrats, r->rats, &num, &den);
1330 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1331 params->rate_num = num;
1332 params->rate_den = den;
1338 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1339 * @runtime: PCM runtime instance
1340 * @cond: condition bits
1341 * @var: hw_params variable to apply the ratnums constraint
1342 * @r: struct snd_ratnums constriants
1344 * Return: Zero if successful, or a negative error code on failure.
1346 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1348 snd_pcm_hw_param_t var,
1349 struct snd_pcm_hw_constraint_ratnums *r)
1351 return snd_pcm_hw_rule_add(runtime, cond, var,
1352 snd_pcm_hw_rule_ratnums, r,
1356 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1358 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1359 struct snd_pcm_hw_rule *rule)
1361 struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1362 unsigned int num = 0, den = 0;
1363 int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1364 r->nrats, r->rats, &num, &den);
1365 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1366 params->rate_num = num;
1367 params->rate_den = den;
1373 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1374 * @runtime: PCM runtime instance
1375 * @cond: condition bits
1376 * @var: hw_params variable to apply the ratdens constraint
1377 * @r: struct snd_ratdens constriants
1379 * Return: Zero if successful, or a negative error code on failure.
1381 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1383 snd_pcm_hw_param_t var,
1384 struct snd_pcm_hw_constraint_ratdens *r)
1386 return snd_pcm_hw_rule_add(runtime, cond, var,
1387 snd_pcm_hw_rule_ratdens, r,
1391 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1393 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1394 struct snd_pcm_hw_rule *rule)
1396 unsigned int l = (unsigned long) rule->private;
1397 int width = l & 0xffff;
1398 unsigned int msbits = l >> 16;
1399 struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1400 if (snd_interval_single(i) && snd_interval_value(i) == width)
1401 params->msbits = msbits;
1406 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1407 * @runtime: PCM runtime instance
1408 * @cond: condition bits
1409 * @width: sample bits width
1410 * @msbits: msbits width
1412 * Return: Zero if successful, or a negative error code on failure.
1414 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1417 unsigned int msbits)
1419 unsigned long l = (msbits << 16) | width;
1420 return snd_pcm_hw_rule_add(runtime, cond, -1,
1421 snd_pcm_hw_rule_msbits,
1423 SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1426 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1428 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1429 struct snd_pcm_hw_rule *rule)
1431 unsigned long step = (unsigned long) rule->private;
1432 return snd_interval_step(hw_param_interval(params, rule->var), step);
1436 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1437 * @runtime: PCM runtime instance
1438 * @cond: condition bits
1439 * @var: hw_params variable to apply the step constraint
1442 * Return: Zero if successful, or a negative error code on failure.
1444 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1446 snd_pcm_hw_param_t var,
1449 return snd_pcm_hw_rule_add(runtime, cond, var,
1450 snd_pcm_hw_rule_step, (void *) step,
1454 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1456 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1458 static unsigned int pow2_sizes[] = {
1459 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1460 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1461 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1462 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1464 return snd_interval_list(hw_param_interval(params, rule->var),
1465 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1469 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1470 * @runtime: PCM runtime instance
1471 * @cond: condition bits
1472 * @var: hw_params variable to apply the power-of-2 constraint
1474 * Return: Zero if successful, or a negative error code on failure.
1476 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1478 snd_pcm_hw_param_t var)
1480 return snd_pcm_hw_rule_add(runtime, cond, var,
1481 snd_pcm_hw_rule_pow2, NULL,
1485 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1487 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1488 struct snd_pcm_hw_rule *rule)
1490 unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1491 struct snd_interval *rate;
1493 rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1494 return snd_interval_list(rate, 1, &base_rate, 0);
1498 * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1499 * @runtime: PCM runtime instance
1500 * @base_rate: the rate at which the hardware does not resample
1502 * Return: Zero if successful, or a negative error code on failure.
1504 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1505 unsigned int base_rate)
1507 return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1508 SNDRV_PCM_HW_PARAM_RATE,
1509 snd_pcm_hw_rule_noresample_func,
1510 (void *)(uintptr_t)base_rate,
1511 SNDRV_PCM_HW_PARAM_RATE, -1);
1513 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1515 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1516 snd_pcm_hw_param_t var)
1518 if (hw_is_mask(var)) {
1519 snd_mask_any(hw_param_mask(params, var));
1520 params->cmask |= 1 << var;
1521 params->rmask |= 1 << var;
1524 if (hw_is_interval(var)) {
1525 snd_interval_any(hw_param_interval(params, var));
1526 params->cmask |= 1 << var;
1527 params->rmask |= 1 << var;
1533 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1536 memset(params, 0, sizeof(*params));
1537 for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1538 _snd_pcm_hw_param_any(params, k);
1539 for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1540 _snd_pcm_hw_param_any(params, k);
1544 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1547 * snd_pcm_hw_param_value - return @params field @var value
1548 * @params: the hw_params instance
1549 * @var: parameter to retrieve
1550 * @dir: pointer to the direction (-1,0,1) or %NULL
1552 * Return: The value for field @var if it's fixed in configuration space
1553 * defined by @params. -%EINVAL otherwise.
1555 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1556 snd_pcm_hw_param_t var, int *dir)
1558 if (hw_is_mask(var)) {
1559 const struct snd_mask *mask = hw_param_mask_c(params, var);
1560 if (!snd_mask_single(mask))
1564 return snd_mask_value(mask);
1566 if (hw_is_interval(var)) {
1567 const struct snd_interval *i = hw_param_interval_c(params, var);
1568 if (!snd_interval_single(i))
1572 return snd_interval_value(i);
1577 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1579 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1580 snd_pcm_hw_param_t var)
1582 if (hw_is_mask(var)) {
1583 snd_mask_none(hw_param_mask(params, var));
1584 params->cmask |= 1 << var;
1585 params->rmask |= 1 << var;
1586 } else if (hw_is_interval(var)) {
1587 snd_interval_none(hw_param_interval(params, var));
1588 params->cmask |= 1 << var;
1589 params->rmask |= 1 << var;
1595 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1597 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1598 snd_pcm_hw_param_t var)
1601 if (hw_is_mask(var))
1602 changed = snd_mask_refine_first(hw_param_mask(params, var));
1603 else if (hw_is_interval(var))
1604 changed = snd_interval_refine_first(hw_param_interval(params, var));
1608 params->cmask |= 1 << var;
1609 params->rmask |= 1 << var;
1616 * snd_pcm_hw_param_first - refine config space and return minimum value
1617 * @pcm: PCM instance
1618 * @params: the hw_params instance
1619 * @var: parameter to retrieve
1620 * @dir: pointer to the direction (-1,0,1) or %NULL
1622 * Inside configuration space defined by @params remove from @var all
1623 * values > minimum. Reduce configuration space accordingly.
1625 * Return: The minimum, or a negative error code on failure.
1627 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1628 struct snd_pcm_hw_params *params,
1629 snd_pcm_hw_param_t var, int *dir)
1631 int changed = _snd_pcm_hw_param_first(params, var);
1634 if (params->rmask) {
1635 int err = snd_pcm_hw_refine(pcm, params);
1636 if (snd_BUG_ON(err < 0))
1639 return snd_pcm_hw_param_value(params, var, dir);
1642 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1644 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1645 snd_pcm_hw_param_t var)
1648 if (hw_is_mask(var))
1649 changed = snd_mask_refine_last(hw_param_mask(params, var));
1650 else if (hw_is_interval(var))
1651 changed = snd_interval_refine_last(hw_param_interval(params, var));
1655 params->cmask |= 1 << var;
1656 params->rmask |= 1 << var;
1663 * snd_pcm_hw_param_last - refine config space and return maximum value
1664 * @pcm: PCM instance
1665 * @params: the hw_params instance
1666 * @var: parameter to retrieve
1667 * @dir: pointer to the direction (-1,0,1) or %NULL
1669 * Inside configuration space defined by @params remove from @var all
1670 * values < maximum. Reduce configuration space accordingly.
1672 * Return: The maximum, or a negative error code on failure.
1674 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1675 struct snd_pcm_hw_params *params,
1676 snd_pcm_hw_param_t var, int *dir)
1678 int changed = _snd_pcm_hw_param_last(params, var);
1681 if (params->rmask) {
1682 int err = snd_pcm_hw_refine(pcm, params);
1683 if (snd_BUG_ON(err < 0))
1686 return snd_pcm_hw_param_value(params, var, dir);
1689 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1692 * snd_pcm_hw_param_choose - choose a configuration defined by @params
1693 * @pcm: PCM instance
1694 * @params: the hw_params instance
1696 * Choose one configuration from configuration space defined by @params.
1697 * The configuration chosen is that obtained fixing in this order:
1698 * first access, first format, first subformat, min channels,
1699 * min rate, min period time, max buffer size, min tick time
1701 * Return: Zero if successful, or a negative error code on failure.
1703 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1704 struct snd_pcm_hw_params *params)
1706 static int vars[] = {
1707 SNDRV_PCM_HW_PARAM_ACCESS,
1708 SNDRV_PCM_HW_PARAM_FORMAT,
1709 SNDRV_PCM_HW_PARAM_SUBFORMAT,
1710 SNDRV_PCM_HW_PARAM_CHANNELS,
1711 SNDRV_PCM_HW_PARAM_RATE,
1712 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1713 SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1714 SNDRV_PCM_HW_PARAM_TICK_TIME,
1719 for (v = vars; *v != -1; v++) {
1720 if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1721 err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1723 err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1724 if (snd_BUG_ON(err < 0))
1730 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1733 struct snd_pcm_runtime *runtime = substream->runtime;
1734 unsigned long flags;
1735 snd_pcm_stream_lock_irqsave(substream, flags);
1736 if (snd_pcm_running(substream) &&
1737 snd_pcm_update_hw_ptr(substream) >= 0)
1738 runtime->status->hw_ptr %= runtime->buffer_size;
1740 runtime->status->hw_ptr = 0;
1741 runtime->hw_ptr_wrap = 0;
1743 snd_pcm_stream_unlock_irqrestore(substream, flags);
1747 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1750 struct snd_pcm_channel_info *info = arg;
1751 struct snd_pcm_runtime *runtime = substream->runtime;
1753 if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1757 width = snd_pcm_format_physical_width(runtime->format);
1761 switch (runtime->access) {
1762 case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1763 case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1764 info->first = info->channel * width;
1765 info->step = runtime->channels * width;
1767 case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1768 case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1770 size_t size = runtime->dma_bytes / runtime->channels;
1771 info->first = info->channel * size * 8;
1782 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1785 struct snd_pcm_hw_params *params = arg;
1786 snd_pcm_format_t format;
1790 params->fifo_size = substream->runtime->hw.fifo_size;
1791 if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1792 format = params_format(params);
1793 channels = params_channels(params);
1794 frame_size = snd_pcm_format_size(format, channels);
1796 params->fifo_size /= (unsigned)frame_size;
1802 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1803 * @substream: the pcm substream instance
1804 * @cmd: ioctl command
1805 * @arg: ioctl argument
1807 * Processes the generic ioctl commands for PCM.
1808 * Can be passed as the ioctl callback for PCM ops.
1810 * Return: Zero if successful, or a negative error code on failure.
1812 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1813 unsigned int cmd, void *arg)
1816 case SNDRV_PCM_IOCTL1_INFO:
1818 case SNDRV_PCM_IOCTL1_RESET:
1819 return snd_pcm_lib_ioctl_reset(substream, arg);
1820 case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1821 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1822 case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1823 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1828 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1831 * snd_pcm_period_elapsed - update the pcm status for the next period
1832 * @substream: the pcm substream instance
1834 * This function is called from the interrupt handler when the
1835 * PCM has processed the period size. It will update the current
1836 * pointer, wake up sleepers, etc.
1838 * Even if more than one periods have elapsed since the last call, you
1839 * have to call this only once.
1841 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1843 struct snd_pcm_runtime *runtime;
1844 unsigned long flags;
1846 if (PCM_RUNTIME_CHECK(substream))
1848 runtime = substream->runtime;
1850 if (runtime->transfer_ack_begin)
1851 runtime->transfer_ack_begin(substream);
1853 snd_pcm_stream_lock_irqsave(substream, flags);
1854 if (!snd_pcm_running(substream) ||
1855 snd_pcm_update_hw_ptr0(substream, 1) < 0)
1858 if (substream->timer_running)
1859 snd_timer_interrupt(substream->timer, 1);
1861 snd_pcm_stream_unlock_irqrestore(substream, flags);
1862 if (runtime->transfer_ack_end)
1863 runtime->transfer_ack_end(substream);
1864 kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1867 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1870 * Wait until avail_min data becomes available
1871 * Returns a negative error code if any error occurs during operation.
1872 * The available space is stored on availp. When err = 0 and avail = 0
1873 * on the capture stream, it indicates the stream is in DRAINING state.
1875 static int wait_for_avail(struct snd_pcm_substream *substream,
1876 snd_pcm_uframes_t *availp)
1878 struct snd_pcm_runtime *runtime = substream->runtime;
1879 int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1882 snd_pcm_uframes_t avail = 0;
1883 long wait_time, tout;
1885 init_waitqueue_entry(&wait, current);
1886 set_current_state(TASK_INTERRUPTIBLE);
1887 add_wait_queue(&runtime->tsleep, &wait);
1889 if (runtime->no_period_wakeup)
1890 wait_time = MAX_SCHEDULE_TIMEOUT;
1893 if (runtime->rate) {
1894 long t = runtime->period_size * 2 / runtime->rate;
1895 wait_time = max(t, wait_time);
1897 wait_time = msecs_to_jiffies(wait_time * 1000);
1901 if (signal_pending(current)) {
1907 * We need to check if space became available already
1908 * (and thus the wakeup happened already) first to close
1909 * the race of space already having become available.
1910 * This check must happen after been added to the waitqueue
1911 * and having current state be INTERRUPTIBLE.
1914 avail = snd_pcm_playback_avail(runtime);
1916 avail = snd_pcm_capture_avail(runtime);
1917 if (avail >= runtime->twake)
1919 snd_pcm_stream_unlock_irq(substream);
1921 tout = schedule_timeout(wait_time);
1923 snd_pcm_stream_lock_irq(substream);
1924 set_current_state(TASK_INTERRUPTIBLE);
1925 switch (runtime->status->state) {
1926 case SNDRV_PCM_STATE_SUSPENDED:
1929 case SNDRV_PCM_STATE_XRUN:
1932 case SNDRV_PCM_STATE_DRAINING:
1936 avail = 0; /* indicate draining */
1938 case SNDRV_PCM_STATE_OPEN:
1939 case SNDRV_PCM_STATE_SETUP:
1940 case SNDRV_PCM_STATE_DISCONNECTED:
1943 case SNDRV_PCM_STATE_PAUSED:
1947 pcm_dbg(substream->pcm,
1948 "%s write error (DMA or IRQ trouble?)\n",
1949 is_playback ? "playback" : "capture");
1955 set_current_state(TASK_RUNNING);
1956 remove_wait_queue(&runtime->tsleep, &wait);
1961 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1963 unsigned long data, unsigned int off,
1964 snd_pcm_uframes_t frames)
1966 struct snd_pcm_runtime *runtime = substream->runtime;
1968 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1969 if (substream->ops->copy) {
1970 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1973 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1974 if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1980 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1981 unsigned long data, unsigned int off,
1982 snd_pcm_uframes_t size);
1984 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1986 snd_pcm_uframes_t size,
1988 transfer_f transfer)
1990 struct snd_pcm_runtime *runtime = substream->runtime;
1991 snd_pcm_uframes_t xfer = 0;
1992 snd_pcm_uframes_t offset = 0;
1993 snd_pcm_uframes_t avail;
1999 snd_pcm_stream_lock_irq(substream);
2000 switch (runtime->status->state) {
2001 case SNDRV_PCM_STATE_PREPARED:
2002 case SNDRV_PCM_STATE_RUNNING:
2003 case SNDRV_PCM_STATE_PAUSED:
2005 case SNDRV_PCM_STATE_XRUN:
2008 case SNDRV_PCM_STATE_SUSPENDED:
2016 runtime->twake = runtime->control->avail_min ? : 1;
2017 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2018 snd_pcm_update_hw_ptr(substream);
2019 avail = snd_pcm_playback_avail(runtime);
2021 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2022 snd_pcm_uframes_t cont;
2028 runtime->twake = min_t(snd_pcm_uframes_t, size,
2029 runtime->control->avail_min ? : 1);
2030 err = wait_for_avail(substream, &avail);
2034 frames = size > avail ? avail : size;
2035 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2038 if (snd_BUG_ON(!frames)) {
2040 snd_pcm_stream_unlock_irq(substream);
2043 appl_ptr = runtime->control->appl_ptr;
2044 appl_ofs = appl_ptr % runtime->buffer_size;
2045 snd_pcm_stream_unlock_irq(substream);
2046 err = transfer(substream, appl_ofs, data, offset, frames);
2047 snd_pcm_stream_lock_irq(substream);
2050 switch (runtime->status->state) {
2051 case SNDRV_PCM_STATE_XRUN:
2054 case SNDRV_PCM_STATE_SUSPENDED:
2061 if (appl_ptr >= runtime->boundary)
2062 appl_ptr -= runtime->boundary;
2063 runtime->control->appl_ptr = appl_ptr;
2064 if (substream->ops->ack)
2065 substream->ops->ack(substream);
2071 if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2072 snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2073 err = snd_pcm_start(substream);
2080 if (xfer > 0 && err >= 0)
2081 snd_pcm_update_state(substream, runtime);
2082 snd_pcm_stream_unlock_irq(substream);
2083 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2086 /* sanity-check for read/write methods */
2087 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2089 struct snd_pcm_runtime *runtime;
2090 if (PCM_RUNTIME_CHECK(substream))
2092 runtime = substream->runtime;
2093 if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
2095 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2100 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
2102 struct snd_pcm_runtime *runtime;
2106 err = pcm_sanity_check(substream);
2109 runtime = substream->runtime;
2110 nonblock = !!(substream->f_flags & O_NONBLOCK);
2112 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2113 runtime->channels > 1)
2115 return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
2116 snd_pcm_lib_write_transfer);
2119 EXPORT_SYMBOL(snd_pcm_lib_write);
2121 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
2123 unsigned long data, unsigned int off,
2124 snd_pcm_uframes_t frames)
2126 struct snd_pcm_runtime *runtime = substream->runtime;
2128 void __user **bufs = (void __user **)data;
2129 int channels = runtime->channels;
2131 if (substream->ops->copy) {
2132 if (snd_BUG_ON(!substream->ops->silence))
2134 for (c = 0; c < channels; ++c, ++bufs) {
2135 if (*bufs == NULL) {
2136 if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
2139 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2140 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2145 /* default transfer behaviour */
2146 size_t dma_csize = runtime->dma_bytes / channels;
2147 for (c = 0; c < channels; ++c, ++bufs) {
2148 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2149 if (*bufs == NULL) {
2150 snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
2152 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2153 if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
2161 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
2163 snd_pcm_uframes_t frames)
2165 struct snd_pcm_runtime *runtime;
2169 err = pcm_sanity_check(substream);
2172 runtime = substream->runtime;
2173 nonblock = !!(substream->f_flags & O_NONBLOCK);
2175 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2177 return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2178 nonblock, snd_pcm_lib_writev_transfer);
2181 EXPORT_SYMBOL(snd_pcm_lib_writev);
2183 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
2185 unsigned long data, unsigned int off,
2186 snd_pcm_uframes_t frames)
2188 struct snd_pcm_runtime *runtime = substream->runtime;
2190 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2191 if (substream->ops->copy) {
2192 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2195 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2196 if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2202 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2204 snd_pcm_uframes_t size,
2206 transfer_f transfer)
2208 struct snd_pcm_runtime *runtime = substream->runtime;
2209 snd_pcm_uframes_t xfer = 0;
2210 snd_pcm_uframes_t offset = 0;
2211 snd_pcm_uframes_t avail;
2217 snd_pcm_stream_lock_irq(substream);
2218 switch (runtime->status->state) {
2219 case SNDRV_PCM_STATE_PREPARED:
2220 if (size >= runtime->start_threshold) {
2221 err = snd_pcm_start(substream);
2226 case SNDRV_PCM_STATE_DRAINING:
2227 case SNDRV_PCM_STATE_RUNNING:
2228 case SNDRV_PCM_STATE_PAUSED:
2230 case SNDRV_PCM_STATE_XRUN:
2233 case SNDRV_PCM_STATE_SUSPENDED:
2241 runtime->twake = runtime->control->avail_min ? : 1;
2242 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2243 snd_pcm_update_hw_ptr(substream);
2244 avail = snd_pcm_capture_avail(runtime);
2246 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2247 snd_pcm_uframes_t cont;
2249 if (runtime->status->state ==
2250 SNDRV_PCM_STATE_DRAINING) {
2251 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2258 runtime->twake = min_t(snd_pcm_uframes_t, size,
2259 runtime->control->avail_min ? : 1);
2260 err = wait_for_avail(substream, &avail);
2264 continue; /* draining */
2266 frames = size > avail ? avail : size;
2267 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2270 if (snd_BUG_ON(!frames)) {
2272 snd_pcm_stream_unlock_irq(substream);
2275 appl_ptr = runtime->control->appl_ptr;
2276 appl_ofs = appl_ptr % runtime->buffer_size;
2277 snd_pcm_stream_unlock_irq(substream);
2278 err = transfer(substream, appl_ofs, data, offset, frames);
2279 snd_pcm_stream_lock_irq(substream);
2282 switch (runtime->status->state) {
2283 case SNDRV_PCM_STATE_XRUN:
2286 case SNDRV_PCM_STATE_SUSPENDED:
2293 if (appl_ptr >= runtime->boundary)
2294 appl_ptr -= runtime->boundary;
2295 runtime->control->appl_ptr = appl_ptr;
2296 if (substream->ops->ack)
2297 substream->ops->ack(substream);
2306 if (xfer > 0 && err >= 0)
2307 snd_pcm_update_state(substream, runtime);
2308 snd_pcm_stream_unlock_irq(substream);
2309 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2312 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2314 struct snd_pcm_runtime *runtime;
2318 err = pcm_sanity_check(substream);
2321 runtime = substream->runtime;
2322 nonblock = !!(substream->f_flags & O_NONBLOCK);
2323 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2325 return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2328 EXPORT_SYMBOL(snd_pcm_lib_read);
2330 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2332 unsigned long data, unsigned int off,
2333 snd_pcm_uframes_t frames)
2335 struct snd_pcm_runtime *runtime = substream->runtime;
2337 void __user **bufs = (void __user **)data;
2338 int channels = runtime->channels;
2340 if (substream->ops->copy) {
2341 for (c = 0; c < channels; ++c, ++bufs) {
2345 buf = *bufs + samples_to_bytes(runtime, off);
2346 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2350 snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2351 for (c = 0; c < channels; ++c, ++bufs) {
2357 hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2358 buf = *bufs + samples_to_bytes(runtime, off);
2359 if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2366 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2368 snd_pcm_uframes_t frames)
2370 struct snd_pcm_runtime *runtime;
2374 err = pcm_sanity_check(substream);
2377 runtime = substream->runtime;
2378 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2381 nonblock = !!(substream->f_flags & O_NONBLOCK);
2382 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2384 return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2387 EXPORT_SYMBOL(snd_pcm_lib_readv);
2390 * standard channel mapping helpers
2393 /* default channel maps for multi-channel playbacks, up to 8 channels */
2394 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2396 .map = { SNDRV_CHMAP_MONO } },
2398 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2400 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2401 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2403 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2404 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2405 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2407 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2408 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2409 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2410 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2413 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2415 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2416 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2418 .map = { SNDRV_CHMAP_MONO } },
2420 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2422 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
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 } },
2429 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2430 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2431 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2432 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2435 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2437 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2439 if (ch > info->max_channels)
2441 return !info->channel_mask || (info->channel_mask & (1U << ch));
2444 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2445 struct snd_ctl_elem_info *uinfo)
2447 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2449 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2451 uinfo->count = info->max_channels;
2452 uinfo->value.integer.min = 0;
2453 uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2457 /* get callback for channel map ctl element
2458 * stores the channel position firstly matching with the current channels
2460 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2461 struct snd_ctl_elem_value *ucontrol)
2463 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2464 unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2465 struct snd_pcm_substream *substream;
2466 const struct snd_pcm_chmap_elem *map;
2468 if (snd_BUG_ON(!info->chmap))
2470 substream = snd_pcm_chmap_substream(info, idx);
2473 memset(ucontrol->value.integer.value, 0,
2474 sizeof(ucontrol->value.integer.value));
2475 if (!substream->runtime)
2476 return 0; /* no channels set */
2477 for (map = info->chmap; map->channels; map++) {
2479 if (map->channels == substream->runtime->channels &&
2480 valid_chmap_channels(info, map->channels)) {
2481 for (i = 0; i < map->channels; i++)
2482 ucontrol->value.integer.value[i] = map->map[i];
2489 /* tlv callback for channel map ctl element
2490 * expands the pre-defined channel maps in a form of TLV
2492 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2493 unsigned int size, unsigned int __user *tlv)
2495 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2496 const struct snd_pcm_chmap_elem *map;
2497 unsigned int __user *dst;
2500 if (snd_BUG_ON(!info->chmap))
2504 if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2508 for (map = info->chmap; map->channels; map++) {
2509 int chs_bytes = map->channels * 4;
2510 if (!valid_chmap_channels(info, map->channels))
2514 if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2515 put_user(chs_bytes, dst + 1))
2520 if (size < chs_bytes)
2524 for (c = 0; c < map->channels; c++) {
2525 if (put_user(map->map[c], dst))
2530 if (put_user(count, tlv + 1))
2535 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2537 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2538 info->pcm->streams[info->stream].chmap_kctl = NULL;
2543 * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2544 * @pcm: the assigned PCM instance
2545 * @stream: stream direction
2546 * @chmap: channel map elements (for query)
2547 * @max_channels: the max number of channels for the stream
2548 * @private_value: the value passed to each kcontrol's private_value field
2549 * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2551 * Create channel-mapping control elements assigned to the given PCM stream(s).
2552 * Return: Zero if successful, or a negative error value.
2554 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2555 const struct snd_pcm_chmap_elem *chmap,
2557 unsigned long private_value,
2558 struct snd_pcm_chmap **info_ret)
2560 struct snd_pcm_chmap *info;
2561 struct snd_kcontrol_new knew = {
2562 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
2563 .access = SNDRV_CTL_ELEM_ACCESS_READ |
2564 SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2565 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2566 .info = pcm_chmap_ctl_info,
2567 .get = pcm_chmap_ctl_get,
2568 .tlv.c = pcm_chmap_ctl_tlv,
2572 info = kzalloc(sizeof(*info), GFP_KERNEL);
2576 info->stream = stream;
2577 info->chmap = chmap;
2578 info->max_channels = max_channels;
2579 if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2580 knew.name = "Playback Channel Map";
2582 knew.name = "Capture Channel Map";
2583 knew.device = pcm->device;
2584 knew.count = pcm->streams[stream].substream_count;
2585 knew.private_value = private_value;
2586 info->kctl = snd_ctl_new1(&knew, info);
2591 info->kctl->private_free = pcm_chmap_ctl_private_free;
2592 err = snd_ctl_add(pcm->card, info->kctl);
2595 pcm->streams[stream].chmap_kctl = info->kctl;
2600 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);