2 * Digital Audio (PCM) abstract layer
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 * Abramo Bagnara <abramo@alsa-project.org>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 #include <linux/slab.h>
24 #include <linux/time.h>
25 #include <linux/math64.h>
26 #include <linux/export.h>
27 #include <sound/core.h>
28 #include <sound/control.h>
29 #include <sound/tlv.h>
30 #include <sound/info.h>
31 #include <sound/pcm.h>
32 #include <sound/pcm_params.h>
33 #include <sound/timer.h>
36 * fill ring buffer with silence
37 * runtime->silence_start: starting pointer to silence area
38 * runtime->silence_filled: size filled with silence
39 * runtime->silence_threshold: threshold from application
40 * runtime->silence_size: maximal size from application
42 * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
44 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
46 struct snd_pcm_runtime *runtime = substream->runtime;
47 snd_pcm_uframes_t frames, ofs, transfer;
49 if (runtime->silence_size < runtime->boundary) {
50 snd_pcm_sframes_t noise_dist, n;
51 if (runtime->silence_start != runtime->control->appl_ptr) {
52 n = runtime->control->appl_ptr - runtime->silence_start;
54 n += runtime->boundary;
55 if ((snd_pcm_uframes_t)n < runtime->silence_filled)
56 runtime->silence_filled -= n;
58 runtime->silence_filled = 0;
59 runtime->silence_start = runtime->control->appl_ptr;
61 if (runtime->silence_filled >= runtime->buffer_size)
63 noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
64 if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
66 frames = runtime->silence_threshold - noise_dist;
67 if (frames > runtime->silence_size)
68 frames = runtime->silence_size;
70 if (new_hw_ptr == ULONG_MAX) { /* initialization */
71 snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
72 if (avail > runtime->buffer_size)
73 avail = runtime->buffer_size;
74 runtime->silence_filled = avail > 0 ? avail : 0;
75 runtime->silence_start = (runtime->status->hw_ptr +
76 runtime->silence_filled) %
79 ofs = runtime->status->hw_ptr;
80 frames = new_hw_ptr - ofs;
81 if ((snd_pcm_sframes_t)frames < 0)
82 frames += runtime->boundary;
83 runtime->silence_filled -= frames;
84 if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
85 runtime->silence_filled = 0;
86 runtime->silence_start = new_hw_ptr;
88 runtime->silence_start = ofs;
91 frames = runtime->buffer_size - runtime->silence_filled;
93 if (snd_BUG_ON(frames > runtime->buffer_size))
97 ofs = runtime->silence_start % runtime->buffer_size;
99 transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
100 if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
101 runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
102 if (substream->ops->silence) {
104 err = substream->ops->silence(substream, -1, ofs, transfer);
107 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
108 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
112 unsigned int channels = runtime->channels;
113 if (substream->ops->silence) {
114 for (c = 0; c < channels; ++c) {
116 err = substream->ops->silence(substream, c, ofs, transfer);
120 size_t dma_csize = runtime->dma_bytes / channels;
121 for (c = 0; c < channels; ++c) {
122 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
123 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
127 runtime->silence_filled += transfer;
133 #ifdef CONFIG_SND_DEBUG
134 void snd_pcm_debug_name(struct snd_pcm_substream *substream,
135 char *name, size_t len)
137 snprintf(name, len, "pcmC%dD%d%c:%d",
138 substream->pcm->card->number,
139 substream->pcm->device,
140 substream->stream ? 'c' : 'p',
143 EXPORT_SYMBOL(snd_pcm_debug_name);
146 #define XRUN_DEBUG_BASIC (1<<0)
147 #define XRUN_DEBUG_STACK (1<<1) /* dump also stack */
148 #define XRUN_DEBUG_JIFFIESCHECK (1<<2) /* do jiffies check */
149 #define XRUN_DEBUG_PERIODUPDATE (1<<3) /* full period update info */
150 #define XRUN_DEBUG_HWPTRUPDATE (1<<4) /* full hwptr update info */
151 #define XRUN_DEBUG_LOG (1<<5) /* show last 10 positions on err */
152 #define XRUN_DEBUG_LOGONCE (1<<6) /* do above only once */
154 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
156 #define xrun_debug(substream, mask) \
157 ((substream)->pstr->xrun_debug & (mask))
159 #define xrun_debug(substream, mask) 0
162 #define dump_stack_on_xrun(substream) do { \
163 if (xrun_debug(substream, XRUN_DEBUG_STACK)) \
167 static void xrun(struct snd_pcm_substream *substream)
169 struct snd_pcm_runtime *runtime = substream->runtime;
171 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
172 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
173 snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
174 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
176 snd_pcm_debug_name(substream, name, sizeof(name));
177 snd_printd(KERN_DEBUG "XRUN: %s\n", name);
178 dump_stack_on_xrun(substream);
182 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
183 #define hw_ptr_error(substream, fmt, args...) \
185 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) { \
186 xrun_log_show(substream); \
187 if (printk_ratelimit()) { \
188 snd_printd("PCM: " fmt, ##args); \
190 dump_stack_on_xrun(substream); \
194 #define XRUN_LOG_CNT 10
196 struct hwptr_log_entry {
197 unsigned int in_interrupt;
198 unsigned long jiffies;
199 snd_pcm_uframes_t pos;
200 snd_pcm_uframes_t period_size;
201 snd_pcm_uframes_t buffer_size;
202 snd_pcm_uframes_t old_hw_ptr;
203 snd_pcm_uframes_t hw_ptr_base;
206 struct snd_pcm_hwptr_log {
209 struct hwptr_log_entry entries[XRUN_LOG_CNT];
212 static void xrun_log(struct snd_pcm_substream *substream,
213 snd_pcm_uframes_t pos, int in_interrupt)
215 struct snd_pcm_runtime *runtime = substream->runtime;
216 struct snd_pcm_hwptr_log *log = runtime->hwptr_log;
217 struct hwptr_log_entry *entry;
220 log = kzalloc(sizeof(*log), GFP_ATOMIC);
223 runtime->hwptr_log = log;
225 if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
228 entry = &log->entries[log->idx];
229 entry->in_interrupt = in_interrupt;
230 entry->jiffies = jiffies;
232 entry->period_size = runtime->period_size;
233 entry->buffer_size = runtime->buffer_size;
234 entry->old_hw_ptr = runtime->status->hw_ptr;
235 entry->hw_ptr_base = runtime->hw_ptr_base;
236 log->idx = (log->idx + 1) % XRUN_LOG_CNT;
239 static void xrun_log_show(struct snd_pcm_substream *substream)
241 struct snd_pcm_hwptr_log *log = substream->runtime->hwptr_log;
242 struct hwptr_log_entry *entry;
249 if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
251 snd_pcm_debug_name(substream, name, sizeof(name));
252 for (cnt = 0, idx = log->idx; cnt < XRUN_LOG_CNT; cnt++) {
253 entry = &log->entries[idx];
254 if (entry->period_size == 0)
256 snd_printd("hwptr log: %s: %sj=%lu, pos=%ld/%ld/%ld, "
258 name, entry->in_interrupt ? "[Q] " : "",
260 (unsigned long)entry->pos,
261 (unsigned long)entry->period_size,
262 (unsigned long)entry->buffer_size,
263 (unsigned long)entry->old_hw_ptr,
264 (unsigned long)entry->hw_ptr_base);
271 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
273 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
274 #define xrun_log(substream, pos, in_interrupt) do { } while (0)
275 #define xrun_log_show(substream) do { } while (0)
279 int snd_pcm_update_state(struct snd_pcm_substream *substream,
280 struct snd_pcm_runtime *runtime)
282 snd_pcm_uframes_t avail;
284 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
285 avail = snd_pcm_playback_avail(runtime);
287 avail = snd_pcm_capture_avail(runtime);
288 if (avail > runtime->avail_max)
289 runtime->avail_max = avail;
290 if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
291 if (avail >= runtime->buffer_size) {
292 snd_pcm_drain_done(substream);
296 if (avail >= runtime->stop_threshold) {
301 if (runtime->twake) {
302 if (avail >= runtime->twake)
303 wake_up(&runtime->tsleep);
304 } else if (avail >= runtime->control->avail_min)
305 wake_up(&runtime->sleep);
309 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
310 unsigned int in_interrupt)
312 struct snd_pcm_runtime *runtime = substream->runtime;
313 snd_pcm_uframes_t pos;
314 snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
315 snd_pcm_sframes_t hdelta, delta;
316 unsigned long jdelta;
317 unsigned long curr_jiffies;
318 struct timespec curr_tstamp;
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 (printk_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, struct snd_pcm_ops *ops)
573 struct snd_pcm_str *stream = &pcm->streams[direction];
574 struct snd_pcm_substream *substream;
576 for (substream = stream->substream; substream != NULL; substream = substream->next)
577 substream->ops = ops;
580 EXPORT_SYMBOL(snd_pcm_set_ops);
583 * snd_pcm_sync - set the PCM sync id
584 * @substream: the pcm substream
586 * Sets the PCM sync identifier for the card.
588 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
590 struct snd_pcm_runtime *runtime = substream->runtime;
592 runtime->sync.id32[0] = substream->pcm->card->number;
593 runtime->sync.id32[1] = -1;
594 runtime->sync.id32[2] = -1;
595 runtime->sync.id32[3] = -1;
598 EXPORT_SYMBOL(snd_pcm_set_sync);
601 * Standard ioctl routine
604 static inline unsigned int div32(unsigned int a, unsigned int b,
615 static inline unsigned int div_down(unsigned int a, unsigned int b)
622 static inline unsigned int div_up(unsigned int a, unsigned int b)
634 static inline unsigned int mul(unsigned int a, unsigned int b)
638 if (div_down(UINT_MAX, a) < b)
643 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
644 unsigned int c, unsigned int *r)
646 u_int64_t n = (u_int64_t) a * b;
652 n = div_u64_rem(n, c, r);
661 * snd_interval_refine - refine the interval value of configurator
662 * @i: the interval value to refine
663 * @v: the interval value to refer to
665 * Refines the interval value with the reference value.
666 * The interval is changed to the range satisfying both intervals.
667 * The interval status (min, max, integer, etc.) are evaluated.
669 * Returns non-zero if the value is changed, zero if not changed.
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 * Returns non-zero if the value is changed, zero if not changed.
870 int snd_interval_ratnum(struct snd_interval *i,
871 unsigned int rats_count, struct snd_ratnum *rats,
872 unsigned int *nump, unsigned int *denp)
874 unsigned int best_num, best_den;
877 struct snd_interval t;
879 unsigned int result_num, result_den;
882 best_num = best_den = best_diff = 0;
883 for (k = 0; k < rats_count; ++k) {
884 unsigned int num = rats[k].num;
886 unsigned int q = i->min;
890 den = div_up(num, q);
891 if (den < rats[k].den_min)
893 if (den > rats[k].den_max)
894 den = rats[k].den_max;
897 r = (den - rats[k].den_min) % rats[k].den_step;
901 diff = num - q * den;
905 diff * best_den < best_diff * den) {
915 t.min = div_down(best_num, best_den);
916 t.openmin = !!(best_num % best_den);
918 result_num = best_num;
919 result_diff = best_diff;
920 result_den = best_den;
921 best_num = best_den = best_diff = 0;
922 for (k = 0; k < rats_count; ++k) {
923 unsigned int num = rats[k].num;
925 unsigned int q = i->max;
931 den = div_down(num, q);
932 if (den > rats[k].den_max)
934 if (den < rats[k].den_min)
935 den = rats[k].den_min;
938 r = (den - rats[k].den_min) % rats[k].den_step;
940 den += rats[k].den_step - r;
942 diff = q * den - num;
946 diff * best_den < best_diff * den) {
956 t.max = div_up(best_num, best_den);
957 t.openmax = !!(best_num % best_den);
959 err = snd_interval_refine(i, &t);
963 if (snd_interval_single(i)) {
964 if (best_diff * result_den < result_diff * best_den) {
965 result_num = best_num;
966 result_den = best_den;
976 EXPORT_SYMBOL(snd_interval_ratnum);
979 * snd_interval_ratden - refine the interval value
980 * @i: interval to refine
981 * @rats_count: number of struct ratden
982 * @rats: struct ratden array
983 * @nump: pointer to store the resultant numerator
984 * @denp: pointer to store the resultant denominator
986 * Returns non-zero if the value is changed, zero if not changed.
988 static int snd_interval_ratden(struct snd_interval *i,
989 unsigned int rats_count, struct snd_ratden *rats,
990 unsigned int *nump, unsigned int *denp)
992 unsigned int best_num, best_diff, best_den;
994 struct snd_interval t;
997 best_num = best_den = best_diff = 0;
998 for (k = 0; k < rats_count; ++k) {
1000 unsigned int den = rats[k].den;
1001 unsigned int q = i->min;
1004 if (num > rats[k].num_max)
1006 if (num < rats[k].num_min)
1007 num = rats[k].num_max;
1010 r = (num - rats[k].num_min) % rats[k].num_step;
1012 num += rats[k].num_step - r;
1014 diff = num - q * den;
1015 if (best_num == 0 ||
1016 diff * best_den < best_diff * den) {
1022 if (best_den == 0) {
1026 t.min = div_down(best_num, best_den);
1027 t.openmin = !!(best_num % best_den);
1029 best_num = best_den = best_diff = 0;
1030 for (k = 0; k < rats_count; ++k) {
1032 unsigned int den = rats[k].den;
1033 unsigned int q = i->max;
1036 if (num < rats[k].num_min)
1038 if (num > rats[k].num_max)
1039 num = rats[k].num_max;
1042 r = (num - rats[k].num_min) % rats[k].num_step;
1046 diff = q * den - num;
1047 if (best_num == 0 ||
1048 diff * best_den < best_diff * den) {
1054 if (best_den == 0) {
1058 t.max = div_up(best_num, best_den);
1059 t.openmax = !!(best_num % best_den);
1061 err = snd_interval_refine(i, &t);
1065 if (snd_interval_single(i)) {
1075 * snd_interval_list - refine the interval value from the list
1076 * @i: the interval value to refine
1077 * @count: the number of elements in the list
1078 * @list: the value list
1079 * @mask: the bit-mask to evaluate
1081 * Refines the interval value from the list.
1082 * When mask is non-zero, only the elements corresponding to bit 1 are
1085 * Returns non-zero if the value is changed, zero if not changed.
1087 int snd_interval_list(struct snd_interval *i, unsigned int count,
1088 const unsigned int *list, unsigned int mask)
1091 struct snd_interval list_range;
1097 snd_interval_any(&list_range);
1098 list_range.min = UINT_MAX;
1100 for (k = 0; k < count; k++) {
1101 if (mask && !(mask & (1 << k)))
1103 if (!snd_interval_test(i, list[k]))
1105 list_range.min = min(list_range.min, list[k]);
1106 list_range.max = max(list_range.max, list[k]);
1108 return snd_interval_refine(i, &list_range);
1111 EXPORT_SYMBOL(snd_interval_list);
1113 static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
1117 n = (i->min - min) % step;
1118 if (n != 0 || i->openmin) {
1122 n = (i->max - min) % step;
1123 if (n != 0 || i->openmax) {
1127 if (snd_interval_checkempty(i)) {
1134 /* Info constraints helpers */
1137 * snd_pcm_hw_rule_add - add the hw-constraint rule
1138 * @runtime: the pcm runtime instance
1139 * @cond: condition bits
1140 * @var: the variable to evaluate
1141 * @func: the evaluation function
1142 * @private: the private data pointer passed to function
1143 * @dep: the dependent variables
1145 * Returns zero if successful, or a negative error code on failure.
1147 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1149 snd_pcm_hw_rule_func_t func, void *private,
1152 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1153 struct snd_pcm_hw_rule *c;
1156 va_start(args, dep);
1157 if (constrs->rules_num >= constrs->rules_all) {
1158 struct snd_pcm_hw_rule *new;
1159 unsigned int new_rules = constrs->rules_all + 16;
1160 new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1165 if (constrs->rules) {
1166 memcpy(new, constrs->rules,
1167 constrs->rules_num * sizeof(*c));
1168 kfree(constrs->rules);
1170 constrs->rules = new;
1171 constrs->rules_all = new_rules;
1173 c = &constrs->rules[constrs->rules_num];
1177 c->private = private;
1180 if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1187 dep = va_arg(args, int);
1189 constrs->rules_num++;
1194 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1197 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1198 * @runtime: PCM runtime instance
1199 * @var: hw_params variable to apply the mask
1200 * @mask: the bitmap mask
1202 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1204 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1207 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1208 struct snd_mask *maskp = constrs_mask(constrs, var);
1209 *maskp->bits &= mask;
1210 memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1211 if (*maskp->bits == 0)
1217 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1218 * @runtime: PCM runtime instance
1219 * @var: hw_params variable to apply the mask
1220 * @mask: the 64bit bitmap mask
1222 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1224 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1227 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1228 struct snd_mask *maskp = constrs_mask(constrs, var);
1229 maskp->bits[0] &= (u_int32_t)mask;
1230 maskp->bits[1] &= (u_int32_t)(mask >> 32);
1231 memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1232 if (! maskp->bits[0] && ! maskp->bits[1])
1238 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1239 * @runtime: PCM runtime instance
1240 * @var: hw_params variable to apply the integer constraint
1242 * Apply the constraint of integer to an interval parameter.
1244 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1246 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1247 return snd_interval_setinteger(constrs_interval(constrs, var));
1250 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1253 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1254 * @runtime: PCM runtime instance
1255 * @var: hw_params variable to apply the range
1256 * @min: the minimal value
1257 * @max: the maximal value
1259 * Apply the min/max range constraint to an interval parameter.
1261 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1262 unsigned int min, unsigned int max)
1264 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1265 struct snd_interval t;
1268 t.openmin = t.openmax = 0;
1270 return snd_interval_refine(constrs_interval(constrs, var), &t);
1273 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1275 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1276 struct snd_pcm_hw_rule *rule)
1278 struct snd_pcm_hw_constraint_list *list = rule->private;
1279 return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1284 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1285 * @runtime: PCM runtime instance
1286 * @cond: condition bits
1287 * @var: hw_params variable to apply the list constraint
1290 * Apply the list of constraints to an interval parameter.
1292 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1294 snd_pcm_hw_param_t var,
1295 const struct snd_pcm_hw_constraint_list *l)
1297 return snd_pcm_hw_rule_add(runtime, cond, var,
1298 snd_pcm_hw_rule_list, (void *)l,
1302 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1304 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1305 struct snd_pcm_hw_rule *rule)
1307 struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1308 unsigned int num = 0, den = 0;
1310 err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1311 r->nrats, r->rats, &num, &den);
1312 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1313 params->rate_num = num;
1314 params->rate_den = den;
1320 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1321 * @runtime: PCM runtime instance
1322 * @cond: condition bits
1323 * @var: hw_params variable to apply the ratnums constraint
1324 * @r: struct snd_ratnums constriants
1326 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1328 snd_pcm_hw_param_t var,
1329 struct snd_pcm_hw_constraint_ratnums *r)
1331 return snd_pcm_hw_rule_add(runtime, cond, var,
1332 snd_pcm_hw_rule_ratnums, r,
1336 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1338 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1339 struct snd_pcm_hw_rule *rule)
1341 struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1342 unsigned int num = 0, den = 0;
1343 int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1344 r->nrats, r->rats, &num, &den);
1345 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1346 params->rate_num = num;
1347 params->rate_den = den;
1353 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1354 * @runtime: PCM runtime instance
1355 * @cond: condition bits
1356 * @var: hw_params variable to apply the ratdens constraint
1357 * @r: struct snd_ratdens constriants
1359 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1361 snd_pcm_hw_param_t var,
1362 struct snd_pcm_hw_constraint_ratdens *r)
1364 return snd_pcm_hw_rule_add(runtime, cond, var,
1365 snd_pcm_hw_rule_ratdens, r,
1369 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1371 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1372 struct snd_pcm_hw_rule *rule)
1374 unsigned int l = (unsigned long) rule->private;
1375 int width = l & 0xffff;
1376 unsigned int msbits = l >> 16;
1377 struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1378 if (snd_interval_single(i) && snd_interval_value(i) == width)
1379 params->msbits = msbits;
1384 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1385 * @runtime: PCM runtime instance
1386 * @cond: condition bits
1387 * @width: sample bits width
1388 * @msbits: msbits width
1390 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1393 unsigned int msbits)
1395 unsigned long l = (msbits << 16) | width;
1396 return snd_pcm_hw_rule_add(runtime, cond, -1,
1397 snd_pcm_hw_rule_msbits,
1399 SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1402 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1404 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1405 struct snd_pcm_hw_rule *rule)
1407 unsigned long step = (unsigned long) rule->private;
1408 return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1412 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1413 * @runtime: PCM runtime instance
1414 * @cond: condition bits
1415 * @var: hw_params variable to apply the step constraint
1418 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1420 snd_pcm_hw_param_t var,
1423 return snd_pcm_hw_rule_add(runtime, cond, var,
1424 snd_pcm_hw_rule_step, (void *) step,
1428 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1430 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1432 static unsigned int pow2_sizes[] = {
1433 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1434 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1435 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1436 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1438 return snd_interval_list(hw_param_interval(params, rule->var),
1439 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1443 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1444 * @runtime: PCM runtime instance
1445 * @cond: condition bits
1446 * @var: hw_params variable to apply the power-of-2 constraint
1448 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1450 snd_pcm_hw_param_t var)
1452 return snd_pcm_hw_rule_add(runtime, cond, var,
1453 snd_pcm_hw_rule_pow2, NULL,
1457 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1459 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1460 struct snd_pcm_hw_rule *rule)
1462 unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1463 struct snd_interval *rate;
1465 rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1466 return snd_interval_list(rate, 1, &base_rate, 0);
1470 * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1471 * @runtime: PCM runtime instance
1472 * @base_rate: the rate at which the hardware does not resample
1474 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1475 unsigned int base_rate)
1477 return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1478 SNDRV_PCM_HW_PARAM_RATE,
1479 snd_pcm_hw_rule_noresample_func,
1480 (void *)(uintptr_t)base_rate,
1481 SNDRV_PCM_HW_PARAM_RATE, -1);
1483 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1485 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1486 snd_pcm_hw_param_t var)
1488 if (hw_is_mask(var)) {
1489 snd_mask_any(hw_param_mask(params, var));
1490 params->cmask |= 1 << var;
1491 params->rmask |= 1 << var;
1494 if (hw_is_interval(var)) {
1495 snd_interval_any(hw_param_interval(params, var));
1496 params->cmask |= 1 << var;
1497 params->rmask |= 1 << var;
1503 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1506 memset(params, 0, sizeof(*params));
1507 for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1508 _snd_pcm_hw_param_any(params, k);
1509 for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1510 _snd_pcm_hw_param_any(params, k);
1514 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1517 * snd_pcm_hw_param_value - return @params field @var value
1518 * @params: the hw_params instance
1519 * @var: parameter to retrieve
1520 * @dir: pointer to the direction (-1,0,1) or %NULL
1522 * Return the value for field @var if it's fixed in configuration space
1523 * defined by @params. Return -%EINVAL otherwise.
1525 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1526 snd_pcm_hw_param_t var, int *dir)
1528 if (hw_is_mask(var)) {
1529 const struct snd_mask *mask = hw_param_mask_c(params, var);
1530 if (!snd_mask_single(mask))
1534 return snd_mask_value(mask);
1536 if (hw_is_interval(var)) {
1537 const struct snd_interval *i = hw_param_interval_c(params, var);
1538 if (!snd_interval_single(i))
1542 return snd_interval_value(i);
1547 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1549 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1550 snd_pcm_hw_param_t var)
1552 if (hw_is_mask(var)) {
1553 snd_mask_none(hw_param_mask(params, var));
1554 params->cmask |= 1 << var;
1555 params->rmask |= 1 << var;
1556 } else if (hw_is_interval(var)) {
1557 snd_interval_none(hw_param_interval(params, var));
1558 params->cmask |= 1 << var;
1559 params->rmask |= 1 << var;
1565 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1567 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1568 snd_pcm_hw_param_t var)
1571 if (hw_is_mask(var))
1572 changed = snd_mask_refine_first(hw_param_mask(params, var));
1573 else if (hw_is_interval(var))
1574 changed = snd_interval_refine_first(hw_param_interval(params, var));
1578 params->cmask |= 1 << var;
1579 params->rmask |= 1 << var;
1586 * snd_pcm_hw_param_first - refine config space and return minimum value
1587 * @pcm: PCM instance
1588 * @params: the hw_params instance
1589 * @var: parameter to retrieve
1590 * @dir: pointer to the direction (-1,0,1) or %NULL
1592 * Inside configuration space defined by @params remove from @var all
1593 * values > minimum. Reduce configuration space accordingly.
1594 * Return the minimum.
1596 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1597 struct snd_pcm_hw_params *params,
1598 snd_pcm_hw_param_t var, int *dir)
1600 int changed = _snd_pcm_hw_param_first(params, var);
1603 if (params->rmask) {
1604 int err = snd_pcm_hw_refine(pcm, params);
1605 if (snd_BUG_ON(err < 0))
1608 return snd_pcm_hw_param_value(params, var, dir);
1611 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1613 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1614 snd_pcm_hw_param_t var)
1617 if (hw_is_mask(var))
1618 changed = snd_mask_refine_last(hw_param_mask(params, var));
1619 else if (hw_is_interval(var))
1620 changed = snd_interval_refine_last(hw_param_interval(params, var));
1624 params->cmask |= 1 << var;
1625 params->rmask |= 1 << var;
1632 * snd_pcm_hw_param_last - refine config space and return maximum value
1633 * @pcm: PCM instance
1634 * @params: the hw_params instance
1635 * @var: parameter to retrieve
1636 * @dir: pointer to the direction (-1,0,1) or %NULL
1638 * Inside configuration space defined by @params remove from @var all
1639 * values < maximum. Reduce configuration space accordingly.
1640 * Return the maximum.
1642 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1643 struct snd_pcm_hw_params *params,
1644 snd_pcm_hw_param_t var, int *dir)
1646 int changed = _snd_pcm_hw_param_last(params, var);
1649 if (params->rmask) {
1650 int err = snd_pcm_hw_refine(pcm, params);
1651 if (snd_BUG_ON(err < 0))
1654 return snd_pcm_hw_param_value(params, var, dir);
1657 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1660 * snd_pcm_hw_param_choose - choose a configuration defined by @params
1661 * @pcm: PCM instance
1662 * @params: the hw_params instance
1664 * Choose one configuration from configuration space defined by @params.
1665 * The configuration chosen is that obtained fixing in this order:
1666 * first access, first format, first subformat, min channels,
1667 * min rate, min period time, max buffer size, min tick time
1669 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1670 struct snd_pcm_hw_params *params)
1672 static int vars[] = {
1673 SNDRV_PCM_HW_PARAM_ACCESS,
1674 SNDRV_PCM_HW_PARAM_FORMAT,
1675 SNDRV_PCM_HW_PARAM_SUBFORMAT,
1676 SNDRV_PCM_HW_PARAM_CHANNELS,
1677 SNDRV_PCM_HW_PARAM_RATE,
1678 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1679 SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1680 SNDRV_PCM_HW_PARAM_TICK_TIME,
1685 for (v = vars; *v != -1; v++) {
1686 if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1687 err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1689 err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1690 if (snd_BUG_ON(err < 0))
1696 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1699 struct snd_pcm_runtime *runtime = substream->runtime;
1700 unsigned long flags;
1701 snd_pcm_stream_lock_irqsave(substream, flags);
1702 if (snd_pcm_running(substream) &&
1703 snd_pcm_update_hw_ptr(substream) >= 0)
1704 runtime->status->hw_ptr %= runtime->buffer_size;
1706 runtime->status->hw_ptr = 0;
1707 runtime->hw_ptr_wrap = 0;
1709 snd_pcm_stream_unlock_irqrestore(substream, flags);
1713 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1716 struct snd_pcm_channel_info *info = arg;
1717 struct snd_pcm_runtime *runtime = substream->runtime;
1719 if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1723 width = snd_pcm_format_physical_width(runtime->format);
1727 switch (runtime->access) {
1728 case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1729 case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1730 info->first = info->channel * width;
1731 info->step = runtime->channels * width;
1733 case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1734 case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1736 size_t size = runtime->dma_bytes / runtime->channels;
1737 info->first = info->channel * size * 8;
1748 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1751 struct snd_pcm_hw_params *params = arg;
1752 snd_pcm_format_t format;
1753 int channels, width;
1755 params->fifo_size = substream->runtime->hw.fifo_size;
1756 if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1757 format = params_format(params);
1758 channels = params_channels(params);
1759 width = snd_pcm_format_physical_width(format);
1760 params->fifo_size /= width * channels;
1766 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1767 * @substream: the pcm substream instance
1768 * @cmd: ioctl command
1769 * @arg: ioctl argument
1771 * Processes the generic ioctl commands for PCM.
1772 * Can be passed as the ioctl callback for PCM ops.
1774 * Returns zero if successful, or a negative error code on failure.
1776 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1777 unsigned int cmd, void *arg)
1780 case SNDRV_PCM_IOCTL1_INFO:
1782 case SNDRV_PCM_IOCTL1_RESET:
1783 return snd_pcm_lib_ioctl_reset(substream, arg);
1784 case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1785 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1786 case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1787 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1792 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1795 * snd_pcm_period_elapsed - update the pcm status for the next period
1796 * @substream: the pcm substream instance
1798 * This function is called from the interrupt handler when the
1799 * PCM has processed the period size. It will update the current
1800 * pointer, wake up sleepers, etc.
1802 * Even if more than one periods have elapsed since the last call, you
1803 * have to call this only once.
1805 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1807 struct snd_pcm_runtime *runtime;
1808 unsigned long flags;
1810 if (PCM_RUNTIME_CHECK(substream))
1812 runtime = substream->runtime;
1814 if (runtime->transfer_ack_begin)
1815 runtime->transfer_ack_begin(substream);
1817 snd_pcm_stream_lock_irqsave(substream, flags);
1818 if (!snd_pcm_running(substream) ||
1819 snd_pcm_update_hw_ptr0(substream, 1) < 0)
1822 if (substream->timer_running)
1823 snd_timer_interrupt(substream->timer, 1);
1825 snd_pcm_stream_unlock_irqrestore(substream, flags);
1826 if (runtime->transfer_ack_end)
1827 runtime->transfer_ack_end(substream);
1828 kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1831 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1834 * Wait until avail_min data becomes available
1835 * Returns a negative error code if any error occurs during operation.
1836 * The available space is stored on availp. When err = 0 and avail = 0
1837 * on the capture stream, it indicates the stream is in DRAINING state.
1839 static int wait_for_avail(struct snd_pcm_substream *substream,
1840 snd_pcm_uframes_t *availp)
1842 struct snd_pcm_runtime *runtime = substream->runtime;
1843 int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1846 snd_pcm_uframes_t avail = 0;
1847 long wait_time, tout;
1849 init_waitqueue_entry(&wait, current);
1850 set_current_state(TASK_INTERRUPTIBLE);
1851 add_wait_queue(&runtime->tsleep, &wait);
1853 if (runtime->no_period_wakeup)
1854 wait_time = MAX_SCHEDULE_TIMEOUT;
1857 if (runtime->rate) {
1858 long t = runtime->period_size * 2 / runtime->rate;
1859 wait_time = max(t, wait_time);
1861 wait_time = msecs_to_jiffies(wait_time * 1000);
1865 if (signal_pending(current)) {
1871 * We need to check if space became available already
1872 * (and thus the wakeup happened already) first to close
1873 * the race of space already having become available.
1874 * This check must happen after been added to the waitqueue
1875 * and having current state be INTERRUPTIBLE.
1878 avail = snd_pcm_playback_avail(runtime);
1880 avail = snd_pcm_capture_avail(runtime);
1881 if (avail >= runtime->twake)
1883 snd_pcm_stream_unlock_irq(substream);
1885 tout = schedule_timeout(wait_time);
1887 snd_pcm_stream_lock_irq(substream);
1888 set_current_state(TASK_INTERRUPTIBLE);
1889 switch (runtime->status->state) {
1890 case SNDRV_PCM_STATE_SUSPENDED:
1893 case SNDRV_PCM_STATE_XRUN:
1896 case SNDRV_PCM_STATE_DRAINING:
1900 avail = 0; /* indicate draining */
1902 case SNDRV_PCM_STATE_OPEN:
1903 case SNDRV_PCM_STATE_SETUP:
1904 case SNDRV_PCM_STATE_DISCONNECTED:
1909 snd_printd("%s write error (DMA or IRQ trouble?)\n",
1910 is_playback ? "playback" : "capture");
1916 set_current_state(TASK_RUNNING);
1917 remove_wait_queue(&runtime->tsleep, &wait);
1922 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1924 unsigned long data, unsigned int off,
1925 snd_pcm_uframes_t frames)
1927 struct snd_pcm_runtime *runtime = substream->runtime;
1929 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1930 if (substream->ops->copy) {
1931 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1934 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1935 if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1941 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1942 unsigned long data, unsigned int off,
1943 snd_pcm_uframes_t size);
1945 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1947 snd_pcm_uframes_t size,
1949 transfer_f transfer)
1951 struct snd_pcm_runtime *runtime = substream->runtime;
1952 snd_pcm_uframes_t xfer = 0;
1953 snd_pcm_uframes_t offset = 0;
1954 snd_pcm_uframes_t avail;
1960 snd_pcm_stream_lock_irq(substream);
1961 switch (runtime->status->state) {
1962 case SNDRV_PCM_STATE_PREPARED:
1963 case SNDRV_PCM_STATE_RUNNING:
1964 case SNDRV_PCM_STATE_PAUSED:
1966 case SNDRV_PCM_STATE_XRUN:
1969 case SNDRV_PCM_STATE_SUSPENDED:
1977 runtime->twake = runtime->control->avail_min ? : 1;
1978 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1979 snd_pcm_update_hw_ptr(substream);
1980 avail = snd_pcm_playback_avail(runtime);
1982 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1983 snd_pcm_uframes_t cont;
1989 runtime->twake = min_t(snd_pcm_uframes_t, size,
1990 runtime->control->avail_min ? : 1);
1991 err = wait_for_avail(substream, &avail);
1995 frames = size > avail ? avail : size;
1996 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1999 if (snd_BUG_ON(!frames)) {
2001 snd_pcm_stream_unlock_irq(substream);
2004 appl_ptr = runtime->control->appl_ptr;
2005 appl_ofs = appl_ptr % runtime->buffer_size;
2006 snd_pcm_stream_unlock_irq(substream);
2007 err = transfer(substream, appl_ofs, data, offset, frames);
2008 snd_pcm_stream_lock_irq(substream);
2011 switch (runtime->status->state) {
2012 case SNDRV_PCM_STATE_XRUN:
2015 case SNDRV_PCM_STATE_SUSPENDED:
2022 if (appl_ptr >= runtime->boundary)
2023 appl_ptr -= runtime->boundary;
2024 runtime->control->appl_ptr = appl_ptr;
2025 if (substream->ops->ack)
2026 substream->ops->ack(substream);
2032 if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2033 snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2034 err = snd_pcm_start(substream);
2041 if (xfer > 0 && err >= 0)
2042 snd_pcm_update_state(substream, runtime);
2043 snd_pcm_stream_unlock_irq(substream);
2044 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2047 /* sanity-check for read/write methods */
2048 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2050 struct snd_pcm_runtime *runtime;
2051 if (PCM_RUNTIME_CHECK(substream))
2053 runtime = substream->runtime;
2054 if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
2056 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2061 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
2063 struct snd_pcm_runtime *runtime;
2067 err = pcm_sanity_check(substream);
2070 runtime = substream->runtime;
2071 nonblock = !!(substream->f_flags & O_NONBLOCK);
2073 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2074 runtime->channels > 1)
2076 return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
2077 snd_pcm_lib_write_transfer);
2080 EXPORT_SYMBOL(snd_pcm_lib_write);
2082 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
2084 unsigned long data, unsigned int off,
2085 snd_pcm_uframes_t frames)
2087 struct snd_pcm_runtime *runtime = substream->runtime;
2089 void __user **bufs = (void __user **)data;
2090 int channels = runtime->channels;
2092 if (substream->ops->copy) {
2093 if (snd_BUG_ON(!substream->ops->silence))
2095 for (c = 0; c < channels; ++c, ++bufs) {
2096 if (*bufs == NULL) {
2097 if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
2100 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2101 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2106 /* default transfer behaviour */
2107 size_t dma_csize = runtime->dma_bytes / channels;
2108 for (c = 0; c < channels; ++c, ++bufs) {
2109 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2110 if (*bufs == NULL) {
2111 snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
2113 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2114 if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
2122 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
2124 snd_pcm_uframes_t frames)
2126 struct snd_pcm_runtime *runtime;
2130 err = pcm_sanity_check(substream);
2133 runtime = substream->runtime;
2134 nonblock = !!(substream->f_flags & O_NONBLOCK);
2136 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2138 return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2139 nonblock, snd_pcm_lib_writev_transfer);
2142 EXPORT_SYMBOL(snd_pcm_lib_writev);
2144 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
2146 unsigned long data, unsigned int off,
2147 snd_pcm_uframes_t frames)
2149 struct snd_pcm_runtime *runtime = substream->runtime;
2151 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2152 if (substream->ops->copy) {
2153 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2156 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2157 if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2163 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2165 snd_pcm_uframes_t size,
2167 transfer_f transfer)
2169 struct snd_pcm_runtime *runtime = substream->runtime;
2170 snd_pcm_uframes_t xfer = 0;
2171 snd_pcm_uframes_t offset = 0;
2172 snd_pcm_uframes_t avail;
2178 snd_pcm_stream_lock_irq(substream);
2179 switch (runtime->status->state) {
2180 case SNDRV_PCM_STATE_PREPARED:
2181 if (size >= runtime->start_threshold) {
2182 err = snd_pcm_start(substream);
2187 case SNDRV_PCM_STATE_DRAINING:
2188 case SNDRV_PCM_STATE_RUNNING:
2189 case SNDRV_PCM_STATE_PAUSED:
2191 case SNDRV_PCM_STATE_XRUN:
2194 case SNDRV_PCM_STATE_SUSPENDED:
2202 runtime->twake = runtime->control->avail_min ? : 1;
2203 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2204 snd_pcm_update_hw_ptr(substream);
2205 avail = snd_pcm_capture_avail(runtime);
2207 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2208 snd_pcm_uframes_t cont;
2210 if (runtime->status->state ==
2211 SNDRV_PCM_STATE_DRAINING) {
2212 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2219 runtime->twake = min_t(snd_pcm_uframes_t, size,
2220 runtime->control->avail_min ? : 1);
2221 err = wait_for_avail(substream, &avail);
2225 continue; /* draining */
2227 frames = size > avail ? avail : size;
2228 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2231 if (snd_BUG_ON(!frames)) {
2233 snd_pcm_stream_unlock_irq(substream);
2236 appl_ptr = runtime->control->appl_ptr;
2237 appl_ofs = appl_ptr % runtime->buffer_size;
2238 snd_pcm_stream_unlock_irq(substream);
2239 err = transfer(substream, appl_ofs, data, offset, frames);
2240 snd_pcm_stream_lock_irq(substream);
2243 switch (runtime->status->state) {
2244 case SNDRV_PCM_STATE_XRUN:
2247 case SNDRV_PCM_STATE_SUSPENDED:
2254 if (appl_ptr >= runtime->boundary)
2255 appl_ptr -= runtime->boundary;
2256 runtime->control->appl_ptr = appl_ptr;
2257 if (substream->ops->ack)
2258 substream->ops->ack(substream);
2267 if (xfer > 0 && err >= 0)
2268 snd_pcm_update_state(substream, runtime);
2269 snd_pcm_stream_unlock_irq(substream);
2270 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2273 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2275 struct snd_pcm_runtime *runtime;
2279 err = pcm_sanity_check(substream);
2282 runtime = substream->runtime;
2283 nonblock = !!(substream->f_flags & O_NONBLOCK);
2284 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2286 return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2289 EXPORT_SYMBOL(snd_pcm_lib_read);
2291 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2293 unsigned long data, unsigned int off,
2294 snd_pcm_uframes_t frames)
2296 struct snd_pcm_runtime *runtime = substream->runtime;
2298 void __user **bufs = (void __user **)data;
2299 int channels = runtime->channels;
2301 if (substream->ops->copy) {
2302 for (c = 0; c < channels; ++c, ++bufs) {
2306 buf = *bufs + samples_to_bytes(runtime, off);
2307 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2311 snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2312 for (c = 0; c < channels; ++c, ++bufs) {
2318 hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2319 buf = *bufs + samples_to_bytes(runtime, off);
2320 if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2327 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2329 snd_pcm_uframes_t frames)
2331 struct snd_pcm_runtime *runtime;
2335 err = pcm_sanity_check(substream);
2338 runtime = substream->runtime;
2339 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2342 nonblock = !!(substream->f_flags & O_NONBLOCK);
2343 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2345 return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2348 EXPORT_SYMBOL(snd_pcm_lib_readv);
2351 * standard channel mapping helpers
2354 /* default channel maps for multi-channel playbacks, up to 8 channels */
2355 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2357 .map = { SNDRV_CHMAP_MONO } },
2359 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2361 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2362 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2364 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2365 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2366 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2368 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2369 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2370 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2371 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2374 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2376 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2377 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2379 .map = { SNDRV_CHMAP_MONO } },
2381 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2383 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2384 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2386 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2387 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2388 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2390 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2391 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2392 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2393 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2396 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2398 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2400 if (ch > info->max_channels)
2402 return !info->channel_mask || (info->channel_mask & (1U << ch));
2405 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2406 struct snd_ctl_elem_info *uinfo)
2408 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2410 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2412 uinfo->count = info->max_channels;
2413 uinfo->value.integer.min = 0;
2414 uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2418 /* get callback for channel map ctl element
2419 * stores the channel position firstly matching with the current channels
2421 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2422 struct snd_ctl_elem_value *ucontrol)
2424 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2425 unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2426 struct snd_pcm_substream *substream;
2427 const struct snd_pcm_chmap_elem *map;
2429 if (snd_BUG_ON(!info->chmap))
2431 substream = snd_pcm_chmap_substream(info, idx);
2434 memset(ucontrol->value.integer.value, 0,
2435 sizeof(ucontrol->value.integer.value));
2436 if (!substream->runtime)
2437 return 0; /* no channels set */
2438 for (map = info->chmap; map->channels; map++) {
2440 if (map->channels == substream->runtime->channels &&
2441 valid_chmap_channels(info, map->channels)) {
2442 for (i = 0; i < map->channels; i++)
2443 ucontrol->value.integer.value[i] = map->map[i];
2450 /* tlv callback for channel map ctl element
2451 * expands the pre-defined channel maps in a form of TLV
2453 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2454 unsigned int size, unsigned int __user *tlv)
2456 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2457 const struct snd_pcm_chmap_elem *map;
2458 unsigned int __user *dst;
2461 if (snd_BUG_ON(!info->chmap))
2465 if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2469 for (map = info->chmap; map->channels; map++) {
2470 int chs_bytes = map->channels * 4;
2471 if (!valid_chmap_channels(info, map->channels))
2475 if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2476 put_user(chs_bytes, dst + 1))
2481 if (size < chs_bytes)
2485 for (c = 0; c < map->channels; c++) {
2486 if (put_user(map->map[c], dst))
2491 if (put_user(count, tlv + 1))
2496 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2498 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2499 info->pcm->streams[info->stream].chmap_kctl = NULL;
2504 * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2505 * @pcm: the assigned PCM instance
2506 * @stream: stream direction
2507 * @chmap: channel map elements (for query)
2508 * @max_channels: the max number of channels for the stream
2509 * @private_value: the value passed to each kcontrol's private_value field
2510 * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2512 * Create channel-mapping control elements assigned to the given PCM stream(s).
2513 * Returns zero if succeed, or a negative error value.
2515 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2516 const struct snd_pcm_chmap_elem *chmap,
2518 unsigned long private_value,
2519 struct snd_pcm_chmap **info_ret)
2521 struct snd_pcm_chmap *info;
2522 struct snd_kcontrol_new knew = {
2523 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
2524 .access = SNDRV_CTL_ELEM_ACCESS_READ |
2525 SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2526 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2527 .info = pcm_chmap_ctl_info,
2528 .get = pcm_chmap_ctl_get,
2529 .tlv.c = pcm_chmap_ctl_tlv,
2533 info = kzalloc(sizeof(*info), GFP_KERNEL);
2537 info->stream = stream;
2538 info->chmap = chmap;
2539 info->max_channels = max_channels;
2540 if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2541 knew.name = "Playback Channel Map";
2543 knew.name = "Capture Channel Map";
2544 knew.device = pcm->device;
2545 knew.count = pcm->streams[stream].substream_count;
2546 knew.private_value = private_value;
2547 info->kctl = snd_ctl_new1(&knew, info);
2552 info->kctl->private_free = pcm_chmap_ctl_private_free;
2553 err = snd_ctl_add(pcm->card, info->kctl);
2556 pcm->streams[stream].chmap_kctl = info->kctl;
2561 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);