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>
35 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
36 #define CREATE_TRACE_POINTS
37 #include "pcm_trace.h"
39 #define trace_hwptr(substream, pos, in_interrupt)
40 #define trace_xrun(substream)
41 #define trace_hw_ptr_error(substream, reason)
45 * fill ring buffer with silence
46 * runtime->silence_start: starting pointer to silence area
47 * runtime->silence_filled: size filled with silence
48 * runtime->silence_threshold: threshold from application
49 * runtime->silence_size: maximal size from application
51 * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
53 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
55 struct snd_pcm_runtime *runtime = substream->runtime;
56 snd_pcm_uframes_t frames, ofs, transfer;
58 if (runtime->silence_size < runtime->boundary) {
59 snd_pcm_sframes_t noise_dist, n;
60 if (runtime->silence_start != runtime->control->appl_ptr) {
61 n = runtime->control->appl_ptr - runtime->silence_start;
63 n += runtime->boundary;
64 if ((snd_pcm_uframes_t)n < runtime->silence_filled)
65 runtime->silence_filled -= n;
67 runtime->silence_filled = 0;
68 runtime->silence_start = runtime->control->appl_ptr;
70 if (runtime->silence_filled >= runtime->buffer_size)
72 noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
73 if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
75 frames = runtime->silence_threshold - noise_dist;
76 if (frames > runtime->silence_size)
77 frames = runtime->silence_size;
79 if (new_hw_ptr == ULONG_MAX) { /* initialization */
80 snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
81 if (avail > runtime->buffer_size)
82 avail = runtime->buffer_size;
83 runtime->silence_filled = avail > 0 ? avail : 0;
84 runtime->silence_start = (runtime->status->hw_ptr +
85 runtime->silence_filled) %
88 ofs = runtime->status->hw_ptr;
89 frames = new_hw_ptr - ofs;
90 if ((snd_pcm_sframes_t)frames < 0)
91 frames += runtime->boundary;
92 runtime->silence_filled -= frames;
93 if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
94 runtime->silence_filled = 0;
95 runtime->silence_start = new_hw_ptr;
97 runtime->silence_start = ofs;
100 frames = runtime->buffer_size - runtime->silence_filled;
102 if (snd_BUG_ON(frames > runtime->buffer_size))
106 ofs = runtime->silence_start % runtime->buffer_size;
108 transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
109 if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
110 runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
111 if (substream->ops->silence) {
113 err = substream->ops->silence(substream, -1, ofs, transfer);
116 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
117 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
121 unsigned int channels = runtime->channels;
122 if (substream->ops->silence) {
123 for (c = 0; c < channels; ++c) {
125 err = substream->ops->silence(substream, c, ofs, transfer);
129 size_t dma_csize = runtime->dma_bytes / channels;
130 for (c = 0; c < channels; ++c) {
131 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
132 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
136 runtime->silence_filled += transfer;
142 #ifdef CONFIG_SND_DEBUG
143 void snd_pcm_debug_name(struct snd_pcm_substream *substream,
144 char *name, size_t len)
146 snprintf(name, len, "pcmC%dD%d%c:%d",
147 substream->pcm->card->number,
148 substream->pcm->device,
149 substream->stream ? 'c' : 'p',
152 EXPORT_SYMBOL(snd_pcm_debug_name);
155 #define XRUN_DEBUG_BASIC (1<<0)
156 #define XRUN_DEBUG_STACK (1<<1) /* dump also stack */
157 #define XRUN_DEBUG_JIFFIESCHECK (1<<2) /* do jiffies check */
159 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
161 #define xrun_debug(substream, mask) \
162 ((substream)->pstr->xrun_debug & (mask))
164 #define xrun_debug(substream, mask) 0
167 #define dump_stack_on_xrun(substream) do { \
168 if (xrun_debug(substream, XRUN_DEBUG_STACK)) \
172 static void xrun(struct snd_pcm_substream *substream)
174 struct snd_pcm_runtime *runtime = substream->runtime;
176 trace_xrun(substream);
177 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
178 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
179 snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
180 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
182 snd_pcm_debug_name(substream, name, sizeof(name));
183 pcm_warn(substream->pcm, "XRUN: %s\n", name);
184 dump_stack_on_xrun(substream);
188 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
189 #define hw_ptr_error(substream, in_interrupt, reason, fmt, args...) \
191 trace_hw_ptr_error(substream, reason); \
192 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) { \
193 pr_err_ratelimited("ALSA: PCM: [%c] " reason ": " fmt, \
194 (in_interrupt) ? 'Q' : 'P', ##args); \
195 dump_stack_on_xrun(substream); \
199 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
201 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
205 int snd_pcm_update_state(struct snd_pcm_substream *substream,
206 struct snd_pcm_runtime *runtime)
208 snd_pcm_uframes_t avail;
210 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
211 avail = snd_pcm_playback_avail(runtime);
213 avail = snd_pcm_capture_avail(runtime);
214 if (avail > runtime->avail_max)
215 runtime->avail_max = avail;
216 if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
217 if (avail >= runtime->buffer_size) {
218 snd_pcm_drain_done(substream);
222 if (avail >= runtime->stop_threshold) {
227 if (runtime->twake) {
228 if (avail >= runtime->twake)
229 wake_up(&runtime->tsleep);
230 } else if (avail >= runtime->control->avail_min)
231 wake_up(&runtime->sleep);
235 static void update_audio_tstamp(struct snd_pcm_substream *substream,
236 struct timespec *curr_tstamp,
237 struct timespec *audio_tstamp)
239 struct snd_pcm_runtime *runtime = substream->runtime;
240 u64 audio_frames, audio_nsecs;
241 struct timespec driver_tstamp;
243 if (runtime->tstamp_mode != SNDRV_PCM_TSTAMP_ENABLE)
246 if (!(substream->ops->get_time_info) ||
247 (runtime->audio_tstamp_report.actual_type ==
248 SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
251 * provide audio timestamp derived from pointer position
252 * add delay only if requested
255 audio_frames = runtime->hw_ptr_wrap + runtime->status->hw_ptr;
257 if (runtime->audio_tstamp_config.report_delay) {
258 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
259 audio_frames -= runtime->delay;
261 audio_frames += runtime->delay;
263 audio_nsecs = div_u64(audio_frames * 1000000000LL,
265 *audio_tstamp = ns_to_timespec(audio_nsecs);
267 if (!timespec_equal(&runtime->status->audio_tstamp, audio_tstamp)) {
268 runtime->status->audio_tstamp = *audio_tstamp;
269 runtime->status->tstamp = *curr_tstamp;
273 * re-take a driver timestamp to let apps detect if the reference tstamp
274 * read by low-level hardware was provided with a delay
276 snd_pcm_gettime(substream->runtime, (struct timespec *)&driver_tstamp);
277 runtime->driver_tstamp = driver_tstamp;
280 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
281 unsigned int in_interrupt)
283 struct snd_pcm_runtime *runtime = substream->runtime;
284 snd_pcm_uframes_t pos;
285 snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
286 snd_pcm_sframes_t hdelta, delta;
287 unsigned long jdelta;
288 unsigned long curr_jiffies;
289 struct timespec curr_tstamp;
290 struct timespec audio_tstamp;
291 int crossed_boundary = 0;
293 old_hw_ptr = runtime->status->hw_ptr;
296 * group pointer, time and jiffies reads to allow for more
297 * accurate correlations/corrections.
298 * The values are stored at the end of this routine after
299 * corrections for hw_ptr position
301 pos = substream->ops->pointer(substream);
302 curr_jiffies = jiffies;
303 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
304 if ((substream->ops->get_time_info) &&
305 (runtime->audio_tstamp_config.type_requested != SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
306 substream->ops->get_time_info(substream, &curr_tstamp,
308 &runtime->audio_tstamp_config,
309 &runtime->audio_tstamp_report);
311 /* re-test in case tstamp type is not supported in hardware and was demoted to DEFAULT */
312 if (runtime->audio_tstamp_report.actual_type == SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)
313 snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
315 snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
318 if (pos == SNDRV_PCM_POS_XRUN) {
322 if (pos >= runtime->buffer_size) {
323 if (printk_ratelimit()) {
325 snd_pcm_debug_name(substream, name, sizeof(name));
326 pcm_err(substream->pcm,
327 "invalid position: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
328 name, pos, runtime->buffer_size,
329 runtime->period_size);
333 pos -= pos % runtime->min_align;
334 trace_hwptr(substream, pos, in_interrupt);
335 hw_base = runtime->hw_ptr_base;
336 new_hw_ptr = hw_base + pos;
338 /* we know that one period was processed */
339 /* delta = "expected next hw_ptr" for in_interrupt != 0 */
340 delta = runtime->hw_ptr_interrupt + runtime->period_size;
341 if (delta > new_hw_ptr) {
342 /* check for double acknowledged interrupts */
343 hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
344 if (hdelta > runtime->hw_ptr_buffer_jiffies/2 + 1) {
345 hw_base += runtime->buffer_size;
346 if (hw_base >= runtime->boundary) {
350 new_hw_ptr = hw_base + pos;
355 /* new_hw_ptr might be lower than old_hw_ptr in case when */
356 /* pointer crosses the end of the ring buffer */
357 if (new_hw_ptr < old_hw_ptr) {
358 hw_base += runtime->buffer_size;
359 if (hw_base >= runtime->boundary) {
363 new_hw_ptr = hw_base + pos;
366 delta = new_hw_ptr - old_hw_ptr;
368 delta += runtime->boundary;
370 if (runtime->no_period_wakeup) {
371 snd_pcm_sframes_t xrun_threshold;
373 * Without regular period interrupts, we have to check
374 * the elapsed time to detect xruns.
376 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
377 if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
379 hdelta = jdelta - delta * HZ / runtime->rate;
380 xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
381 while (hdelta > xrun_threshold) {
382 delta += runtime->buffer_size;
383 hw_base += runtime->buffer_size;
384 if (hw_base >= runtime->boundary) {
388 new_hw_ptr = hw_base + pos;
389 hdelta -= runtime->hw_ptr_buffer_jiffies;
394 /* something must be really wrong */
395 if (delta >= runtime->buffer_size + runtime->period_size) {
396 hw_ptr_error(substream, in_interrupt, "Unexpected hw_ptr",
397 "(stream=%i, pos=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
398 substream->stream, (long)pos,
399 (long)new_hw_ptr, (long)old_hw_ptr);
403 /* Do jiffies check only in xrun_debug mode */
404 if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
405 goto no_jiffies_check;
407 /* Skip the jiffies check for hardwares with BATCH flag.
408 * Such hardware usually just increases the position at each IRQ,
409 * thus it can't give any strange position.
411 if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
412 goto no_jiffies_check;
414 if (hdelta < runtime->delay)
415 goto no_jiffies_check;
416 hdelta -= runtime->delay;
417 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
418 if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
420 (((runtime->period_size * HZ) / runtime->rate)
422 /* move new_hw_ptr according jiffies not pos variable */
423 new_hw_ptr = old_hw_ptr;
425 /* use loop to avoid checks for delta overflows */
426 /* the delta value is small or zero in most cases */
428 new_hw_ptr += runtime->period_size;
429 if (new_hw_ptr >= runtime->boundary) {
430 new_hw_ptr -= runtime->boundary;
435 /* align hw_base to buffer_size */
436 hw_ptr_error(substream, in_interrupt, "hw_ptr skipping",
437 "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
438 (long)pos, (long)hdelta,
439 (long)runtime->period_size, jdelta,
440 ((hdelta * HZ) / runtime->rate), hw_base,
441 (unsigned long)old_hw_ptr,
442 (unsigned long)new_hw_ptr);
443 /* reset values to proper state */
445 hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
448 if (delta > runtime->period_size + runtime->period_size / 2) {
449 hw_ptr_error(substream, in_interrupt,
451 "(stream=%i, delta=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
452 substream->stream, (long)delta,
458 if (runtime->status->hw_ptr == new_hw_ptr) {
459 runtime->hw_ptr_jiffies = curr_jiffies;
460 update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
464 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
465 runtime->silence_size > 0)
466 snd_pcm_playback_silence(substream, new_hw_ptr);
469 delta = new_hw_ptr - runtime->hw_ptr_interrupt;
471 delta += runtime->boundary;
472 delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
473 runtime->hw_ptr_interrupt += delta;
474 if (runtime->hw_ptr_interrupt >= runtime->boundary)
475 runtime->hw_ptr_interrupt -= runtime->boundary;
477 runtime->hw_ptr_base = hw_base;
478 runtime->status->hw_ptr = new_hw_ptr;
479 runtime->hw_ptr_jiffies = curr_jiffies;
480 if (crossed_boundary) {
481 snd_BUG_ON(crossed_boundary != 1);
482 runtime->hw_ptr_wrap += runtime->boundary;
485 update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
487 return snd_pcm_update_state(substream, runtime);
490 /* CAUTION: call it with irq disabled */
491 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
493 return snd_pcm_update_hw_ptr0(substream, 0);
497 * snd_pcm_set_ops - set the PCM operators
498 * @pcm: the pcm instance
499 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
500 * @ops: the operator table
502 * Sets the given PCM operators to the pcm instance.
504 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
505 const struct snd_pcm_ops *ops)
507 struct snd_pcm_str *stream = &pcm->streams[direction];
508 struct snd_pcm_substream *substream;
510 for (substream = stream->substream; substream != NULL; substream = substream->next)
511 substream->ops = ops;
514 EXPORT_SYMBOL(snd_pcm_set_ops);
517 * snd_pcm_sync - set the PCM sync id
518 * @substream: the pcm substream
520 * Sets the PCM sync identifier for the card.
522 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
524 struct snd_pcm_runtime *runtime = substream->runtime;
526 runtime->sync.id32[0] = substream->pcm->card->number;
527 runtime->sync.id32[1] = -1;
528 runtime->sync.id32[2] = -1;
529 runtime->sync.id32[3] = -1;
532 EXPORT_SYMBOL(snd_pcm_set_sync);
535 * Standard ioctl routine
538 static inline unsigned int div32(unsigned int a, unsigned int b,
549 static inline unsigned int div_down(unsigned int a, unsigned int b)
556 static inline unsigned int div_up(unsigned int a, unsigned int b)
568 static inline unsigned int mul(unsigned int a, unsigned int b)
572 if (div_down(UINT_MAX, a) < b)
577 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
578 unsigned int c, unsigned int *r)
580 u_int64_t n = (u_int64_t) a * b;
585 n = div_u64_rem(n, c, r);
594 * snd_interval_refine - refine the interval value of configurator
595 * @i: the interval value to refine
596 * @v: the interval value to refer to
598 * Refines the interval value with the reference value.
599 * The interval is changed to the range satisfying both intervals.
600 * The interval status (min, max, integer, etc.) are evaluated.
602 * Return: Positive if the value is changed, zero if it's not changed, or a
603 * negative error code.
605 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
608 if (snd_BUG_ON(snd_interval_empty(i)))
610 if (i->min < v->min) {
612 i->openmin = v->openmin;
614 } else if (i->min == v->min && !i->openmin && v->openmin) {
618 if (i->max > v->max) {
620 i->openmax = v->openmax;
622 } else if (i->max == v->max && !i->openmax && v->openmax) {
626 if (!i->integer && v->integer) {
639 } else if (!i->openmin && !i->openmax && i->min == i->max)
641 if (snd_interval_checkempty(i)) {
642 snd_interval_none(i);
648 EXPORT_SYMBOL(snd_interval_refine);
650 static int snd_interval_refine_first(struct snd_interval *i)
652 const unsigned int last_max = i->max;
654 if (snd_BUG_ON(snd_interval_empty(i)))
656 if (snd_interval_single(i))
661 /* only exclude max value if also excluded before refine */
662 i->openmax = (i->openmax && i->max >= last_max);
666 static int snd_interval_refine_last(struct snd_interval *i)
668 const unsigned int last_min = i->min;
670 if (snd_BUG_ON(snd_interval_empty(i)))
672 if (snd_interval_single(i))
677 /* only exclude min value if also excluded before refine */
678 i->openmin = (i->openmin && i->min <= last_min);
682 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
684 if (a->empty || b->empty) {
685 snd_interval_none(c);
689 c->min = mul(a->min, b->min);
690 c->openmin = (a->openmin || b->openmin);
691 c->max = mul(a->max, b->max);
692 c->openmax = (a->openmax || b->openmax);
693 c->integer = (a->integer && b->integer);
697 * snd_interval_div - refine the interval value with division
704 * Returns non-zero if the value is changed, zero if not changed.
706 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
709 if (a->empty || b->empty) {
710 snd_interval_none(c);
714 c->min = div32(a->min, b->max, &r);
715 c->openmin = (r || a->openmin || b->openmax);
717 c->max = div32(a->max, b->min, &r);
722 c->openmax = (a->openmax || b->openmin);
731 * snd_interval_muldivk - refine the interval value
734 * @k: divisor (as integer)
739 * Returns non-zero if the value is changed, zero if not changed.
741 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
742 unsigned int k, struct snd_interval *c)
745 if (a->empty || b->empty) {
746 snd_interval_none(c);
750 c->min = muldiv32(a->min, b->min, k, &r);
751 c->openmin = (r || a->openmin || b->openmin);
752 c->max = muldiv32(a->max, b->max, k, &r);
757 c->openmax = (a->openmax || b->openmax);
762 * snd_interval_mulkdiv - refine the interval value
764 * @k: dividend 2 (as integer)
770 * Returns non-zero if the value is changed, zero if not changed.
772 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
773 const struct snd_interval *b, struct snd_interval *c)
776 if (a->empty || b->empty) {
777 snd_interval_none(c);
781 c->min = muldiv32(a->min, k, b->max, &r);
782 c->openmin = (r || a->openmin || b->openmax);
784 c->max = muldiv32(a->max, k, b->min, &r);
789 c->openmax = (a->openmax || b->openmin);
801 * snd_interval_ratnum - refine the interval value
802 * @i: interval to refine
803 * @rats_count: number of ratnum_t
804 * @rats: ratnum_t array
805 * @nump: pointer to store the resultant numerator
806 * @denp: pointer to store the resultant denominator
808 * Return: Positive if the value is changed, zero if it's not changed, or a
809 * negative error code.
811 int snd_interval_ratnum(struct snd_interval *i,
812 unsigned int rats_count, const struct snd_ratnum *rats,
813 unsigned int *nump, unsigned int *denp)
815 unsigned int best_num, best_den;
818 struct snd_interval t;
820 unsigned int result_num, result_den;
823 best_num = best_den = best_diff = 0;
824 for (k = 0; k < rats_count; ++k) {
825 unsigned int num = rats[k].num;
827 unsigned int q = i->min;
831 den = div_up(num, q);
832 if (den < rats[k].den_min)
834 if (den > rats[k].den_max)
835 den = rats[k].den_max;
838 r = (den - rats[k].den_min) % rats[k].den_step;
842 diff = num - q * den;
846 diff * best_den < best_diff * den) {
856 t.min = div_down(best_num, best_den);
857 t.openmin = !!(best_num % best_den);
859 result_num = best_num;
860 result_diff = best_diff;
861 result_den = best_den;
862 best_num = best_den = best_diff = 0;
863 for (k = 0; k < rats_count; ++k) {
864 unsigned int num = rats[k].num;
866 unsigned int q = i->max;
872 den = div_down(num, q);
873 if (den > rats[k].den_max)
875 if (den < rats[k].den_min)
876 den = rats[k].den_min;
879 r = (den - rats[k].den_min) % rats[k].den_step;
881 den += rats[k].den_step - r;
883 diff = q * den - num;
887 diff * best_den < best_diff * den) {
897 t.max = div_up(best_num, best_den);
898 t.openmax = !!(best_num % best_den);
900 err = snd_interval_refine(i, &t);
904 if (snd_interval_single(i)) {
905 if (best_diff * result_den < result_diff * best_den) {
906 result_num = best_num;
907 result_den = best_den;
917 EXPORT_SYMBOL(snd_interval_ratnum);
920 * snd_interval_ratden - refine the interval value
921 * @i: interval to refine
922 * @rats_count: number of struct ratden
923 * @rats: struct ratden array
924 * @nump: pointer to store the resultant numerator
925 * @denp: pointer to store the resultant denominator
927 * Return: Positive if the value is changed, zero if it's not changed, or a
928 * negative error code.
930 static int snd_interval_ratden(struct snd_interval *i,
931 unsigned int rats_count,
932 const struct snd_ratden *rats,
933 unsigned int *nump, unsigned int *denp)
935 unsigned int best_num, best_diff, best_den;
937 struct snd_interval t;
940 best_num = best_den = best_diff = 0;
941 for (k = 0; k < rats_count; ++k) {
943 unsigned int den = rats[k].den;
944 unsigned int q = i->min;
947 if (num > rats[k].num_max)
949 if (num < rats[k].num_min)
950 num = rats[k].num_max;
953 r = (num - rats[k].num_min) % rats[k].num_step;
955 num += rats[k].num_step - r;
957 diff = num - q * den;
959 diff * best_den < best_diff * den) {
969 t.min = div_down(best_num, best_den);
970 t.openmin = !!(best_num % best_den);
972 best_num = best_den = best_diff = 0;
973 for (k = 0; k < rats_count; ++k) {
975 unsigned int den = rats[k].den;
976 unsigned int q = i->max;
979 if (num < rats[k].num_min)
981 if (num > rats[k].num_max)
982 num = rats[k].num_max;
985 r = (num - rats[k].num_min) % rats[k].num_step;
989 diff = q * den - num;
991 diff * best_den < best_diff * den) {
1001 t.max = div_up(best_num, best_den);
1002 t.openmax = !!(best_num % best_den);
1004 err = snd_interval_refine(i, &t);
1008 if (snd_interval_single(i)) {
1018 * snd_interval_list - refine the interval value from the list
1019 * @i: the interval value to refine
1020 * @count: the number of elements in the list
1021 * @list: the value list
1022 * @mask: the bit-mask to evaluate
1024 * Refines the interval value from the list.
1025 * When mask is non-zero, only the elements corresponding to bit 1 are
1028 * Return: Positive if the value is changed, zero if it's not changed, or a
1029 * negative error code.
1031 int snd_interval_list(struct snd_interval *i, unsigned int count,
1032 const unsigned int *list, unsigned int mask)
1035 struct snd_interval list_range;
1041 snd_interval_any(&list_range);
1042 list_range.min = UINT_MAX;
1044 for (k = 0; k < count; k++) {
1045 if (mask && !(mask & (1 << k)))
1047 if (!snd_interval_test(i, list[k]))
1049 list_range.min = min(list_range.min, list[k]);
1050 list_range.max = max(list_range.max, list[k]);
1052 return snd_interval_refine(i, &list_range);
1055 EXPORT_SYMBOL(snd_interval_list);
1058 * snd_interval_ranges - refine the interval value from the list of ranges
1059 * @i: the interval value to refine
1060 * @count: the number of elements in the list of ranges
1061 * @ranges: the ranges list
1062 * @mask: the bit-mask to evaluate
1064 * Refines the interval value from the list of ranges.
1065 * When mask is non-zero, only the elements corresponding to bit 1 are
1068 * Return: Positive if the value is changed, zero if it's not changed, or a
1069 * negative error code.
1071 int snd_interval_ranges(struct snd_interval *i, unsigned int count,
1072 const struct snd_interval *ranges, unsigned int mask)
1075 struct snd_interval range_union;
1076 struct snd_interval range;
1079 snd_interval_none(i);
1082 snd_interval_any(&range_union);
1083 range_union.min = UINT_MAX;
1084 range_union.max = 0;
1085 for (k = 0; k < count; k++) {
1086 if (mask && !(mask & (1 << k)))
1088 snd_interval_copy(&range, &ranges[k]);
1089 if (snd_interval_refine(&range, i) < 0)
1091 if (snd_interval_empty(&range))
1094 if (range.min < range_union.min) {
1095 range_union.min = range.min;
1096 range_union.openmin = 1;
1098 if (range.min == range_union.min && !range.openmin)
1099 range_union.openmin = 0;
1100 if (range.max > range_union.max) {
1101 range_union.max = range.max;
1102 range_union.openmax = 1;
1104 if (range.max == range_union.max && !range.openmax)
1105 range_union.openmax = 0;
1107 return snd_interval_refine(i, &range_union);
1109 EXPORT_SYMBOL(snd_interval_ranges);
1111 static int snd_interval_step(struct snd_interval *i, unsigned int step)
1116 if (n != 0 || i->openmin) {
1122 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 * Return: 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 * Return: Zero if successful, or a negative error code on failure.
1206 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1209 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1210 struct snd_mask *maskp = constrs_mask(constrs, var);
1211 *maskp->bits &= mask;
1212 memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1213 if (*maskp->bits == 0)
1219 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1220 * @runtime: PCM runtime instance
1221 * @var: hw_params variable to apply the mask
1222 * @mask: the 64bit bitmap mask
1224 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1226 * Return: Zero if successful, or a negative error code on failure.
1228 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1231 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1232 struct snd_mask *maskp = constrs_mask(constrs, var);
1233 maskp->bits[0] &= (u_int32_t)mask;
1234 maskp->bits[1] &= (u_int32_t)(mask >> 32);
1235 memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1236 if (! maskp->bits[0] && ! maskp->bits[1])
1240 EXPORT_SYMBOL(snd_pcm_hw_constraint_mask64);
1243 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1244 * @runtime: PCM runtime instance
1245 * @var: hw_params variable to apply the integer constraint
1247 * Apply the constraint of integer to an interval parameter.
1249 * Return: Positive if the value is changed, zero if it's not changed, or a
1250 * negative error code.
1252 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1254 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1255 return snd_interval_setinteger(constrs_interval(constrs, var));
1258 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1261 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1262 * @runtime: PCM runtime instance
1263 * @var: hw_params variable to apply the range
1264 * @min: the minimal value
1265 * @max: the maximal value
1267 * Apply the min/max range constraint to an interval parameter.
1269 * Return: Positive if the value is changed, zero if it's not changed, or a
1270 * negative error code.
1272 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1273 unsigned int min, unsigned int max)
1275 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1276 struct snd_interval t;
1279 t.openmin = t.openmax = 0;
1281 return snd_interval_refine(constrs_interval(constrs, var), &t);
1284 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1286 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1287 struct snd_pcm_hw_rule *rule)
1289 struct snd_pcm_hw_constraint_list *list = rule->private;
1290 return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1295 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1296 * @runtime: PCM runtime instance
1297 * @cond: condition bits
1298 * @var: hw_params variable to apply the list constraint
1301 * Apply the list of constraints to an interval parameter.
1303 * Return: Zero if successful, or a negative error code on failure.
1305 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1307 snd_pcm_hw_param_t var,
1308 const struct snd_pcm_hw_constraint_list *l)
1310 return snd_pcm_hw_rule_add(runtime, cond, var,
1311 snd_pcm_hw_rule_list, (void *)l,
1315 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1317 static int snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params *params,
1318 struct snd_pcm_hw_rule *rule)
1320 struct snd_pcm_hw_constraint_ranges *r = rule->private;
1321 return snd_interval_ranges(hw_param_interval(params, rule->var),
1322 r->count, r->ranges, r->mask);
1327 * snd_pcm_hw_constraint_ranges - apply list of range constraints to a parameter
1328 * @runtime: PCM runtime instance
1329 * @cond: condition bits
1330 * @var: hw_params variable to apply the list of range constraints
1333 * Apply the list of range constraints to an interval parameter.
1335 * Return: Zero if successful, or a negative error code on failure.
1337 int snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime *runtime,
1339 snd_pcm_hw_param_t var,
1340 const struct snd_pcm_hw_constraint_ranges *r)
1342 return snd_pcm_hw_rule_add(runtime, cond, var,
1343 snd_pcm_hw_rule_ranges, (void *)r,
1346 EXPORT_SYMBOL(snd_pcm_hw_constraint_ranges);
1348 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1349 struct snd_pcm_hw_rule *rule)
1351 const struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1352 unsigned int num = 0, den = 0;
1354 err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1355 r->nrats, r->rats, &num, &den);
1356 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1357 params->rate_num = num;
1358 params->rate_den = den;
1364 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1365 * @runtime: PCM runtime instance
1366 * @cond: condition bits
1367 * @var: hw_params variable to apply the ratnums constraint
1368 * @r: struct snd_ratnums constriants
1370 * Return: Zero if successful, or a negative error code on failure.
1372 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1374 snd_pcm_hw_param_t var,
1375 const struct snd_pcm_hw_constraint_ratnums *r)
1377 return snd_pcm_hw_rule_add(runtime, cond, var,
1378 snd_pcm_hw_rule_ratnums, (void *)r,
1382 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1384 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1385 struct snd_pcm_hw_rule *rule)
1387 const struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1388 unsigned int num = 0, den = 0;
1389 int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1390 r->nrats, r->rats, &num, &den);
1391 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1392 params->rate_num = num;
1393 params->rate_den = den;
1399 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1400 * @runtime: PCM runtime instance
1401 * @cond: condition bits
1402 * @var: hw_params variable to apply the ratdens constraint
1403 * @r: struct snd_ratdens constriants
1405 * Return: Zero if successful, or a negative error code on failure.
1407 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1409 snd_pcm_hw_param_t var,
1410 const struct snd_pcm_hw_constraint_ratdens *r)
1412 return snd_pcm_hw_rule_add(runtime, cond, var,
1413 snd_pcm_hw_rule_ratdens, (void *)r,
1417 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1419 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1420 struct snd_pcm_hw_rule *rule)
1422 unsigned int l = (unsigned long) rule->private;
1423 int width = l & 0xffff;
1424 unsigned int msbits = l >> 16;
1425 struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1427 if (!snd_interval_single(i))
1430 if ((snd_interval_value(i) == width) ||
1431 (width == 0 && snd_interval_value(i) > msbits))
1432 params->msbits = min_not_zero(params->msbits, msbits);
1438 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1439 * @runtime: PCM runtime instance
1440 * @cond: condition bits
1441 * @width: sample bits width
1442 * @msbits: msbits width
1444 * This constraint will set the number of most significant bits (msbits) if a
1445 * sample format with the specified width has been select. If width is set to 0
1446 * the msbits will be set for any sample format with a width larger than the
1449 * Return: Zero if successful, or a negative error code on failure.
1451 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1454 unsigned int msbits)
1456 unsigned long l = (msbits << 16) | width;
1457 return snd_pcm_hw_rule_add(runtime, cond, -1,
1458 snd_pcm_hw_rule_msbits,
1460 SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1463 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1465 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1466 struct snd_pcm_hw_rule *rule)
1468 unsigned long step = (unsigned long) rule->private;
1469 return snd_interval_step(hw_param_interval(params, rule->var), step);
1473 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1474 * @runtime: PCM runtime instance
1475 * @cond: condition bits
1476 * @var: hw_params variable to apply the step constraint
1479 * Return: Zero if successful, or a negative error code on failure.
1481 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1483 snd_pcm_hw_param_t var,
1486 return snd_pcm_hw_rule_add(runtime, cond, var,
1487 snd_pcm_hw_rule_step, (void *) step,
1491 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1493 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1495 static unsigned int pow2_sizes[] = {
1496 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1497 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1498 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1499 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1501 return snd_interval_list(hw_param_interval(params, rule->var),
1502 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1506 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1507 * @runtime: PCM runtime instance
1508 * @cond: condition bits
1509 * @var: hw_params variable to apply the power-of-2 constraint
1511 * Return: Zero if successful, or a negative error code on failure.
1513 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1515 snd_pcm_hw_param_t var)
1517 return snd_pcm_hw_rule_add(runtime, cond, var,
1518 snd_pcm_hw_rule_pow2, NULL,
1522 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1524 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1525 struct snd_pcm_hw_rule *rule)
1527 unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1528 struct snd_interval *rate;
1530 rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1531 return snd_interval_list(rate, 1, &base_rate, 0);
1535 * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1536 * @runtime: PCM runtime instance
1537 * @base_rate: the rate at which the hardware does not resample
1539 * Return: Zero if successful, or a negative error code on failure.
1541 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1542 unsigned int base_rate)
1544 return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1545 SNDRV_PCM_HW_PARAM_RATE,
1546 snd_pcm_hw_rule_noresample_func,
1547 (void *)(uintptr_t)base_rate,
1548 SNDRV_PCM_HW_PARAM_RATE, -1);
1550 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1552 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1553 snd_pcm_hw_param_t var)
1555 if (hw_is_mask(var)) {
1556 snd_mask_any(hw_param_mask(params, var));
1557 params->cmask |= 1 << var;
1558 params->rmask |= 1 << var;
1561 if (hw_is_interval(var)) {
1562 snd_interval_any(hw_param_interval(params, var));
1563 params->cmask |= 1 << var;
1564 params->rmask |= 1 << var;
1570 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1573 memset(params, 0, sizeof(*params));
1574 for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1575 _snd_pcm_hw_param_any(params, k);
1576 for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1577 _snd_pcm_hw_param_any(params, k);
1581 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1584 * snd_pcm_hw_param_value - return @params field @var value
1585 * @params: the hw_params instance
1586 * @var: parameter to retrieve
1587 * @dir: pointer to the direction (-1,0,1) or %NULL
1589 * Return: The value for field @var if it's fixed in configuration space
1590 * defined by @params. -%EINVAL otherwise.
1592 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1593 snd_pcm_hw_param_t var, int *dir)
1595 if (hw_is_mask(var)) {
1596 const struct snd_mask *mask = hw_param_mask_c(params, var);
1597 if (!snd_mask_single(mask))
1601 return snd_mask_value(mask);
1603 if (hw_is_interval(var)) {
1604 const struct snd_interval *i = hw_param_interval_c(params, var);
1605 if (!snd_interval_single(i))
1609 return snd_interval_value(i);
1614 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1616 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1617 snd_pcm_hw_param_t var)
1619 if (hw_is_mask(var)) {
1620 snd_mask_none(hw_param_mask(params, var));
1621 params->cmask |= 1 << var;
1622 params->rmask |= 1 << var;
1623 } else if (hw_is_interval(var)) {
1624 snd_interval_none(hw_param_interval(params, var));
1625 params->cmask |= 1 << var;
1626 params->rmask |= 1 << var;
1632 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1634 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1635 snd_pcm_hw_param_t var)
1638 if (hw_is_mask(var))
1639 changed = snd_mask_refine_first(hw_param_mask(params, var));
1640 else if (hw_is_interval(var))
1641 changed = snd_interval_refine_first(hw_param_interval(params, var));
1645 params->cmask |= 1 << var;
1646 params->rmask |= 1 << var;
1653 * snd_pcm_hw_param_first - refine config space and return minimum value
1654 * @pcm: PCM instance
1655 * @params: the hw_params instance
1656 * @var: parameter to retrieve
1657 * @dir: pointer to the direction (-1,0,1) or %NULL
1659 * Inside configuration space defined by @params remove from @var all
1660 * values > minimum. Reduce configuration space accordingly.
1662 * Return: The minimum, or a negative error code on failure.
1664 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1665 struct snd_pcm_hw_params *params,
1666 snd_pcm_hw_param_t var, int *dir)
1668 int changed = _snd_pcm_hw_param_first(params, var);
1671 if (params->rmask) {
1672 int err = snd_pcm_hw_refine(pcm, params);
1676 return snd_pcm_hw_param_value(params, var, dir);
1679 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1681 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1682 snd_pcm_hw_param_t var)
1685 if (hw_is_mask(var))
1686 changed = snd_mask_refine_last(hw_param_mask(params, var));
1687 else if (hw_is_interval(var))
1688 changed = snd_interval_refine_last(hw_param_interval(params, var));
1692 params->cmask |= 1 << var;
1693 params->rmask |= 1 << var;
1700 * snd_pcm_hw_param_last - refine config space and return maximum value
1701 * @pcm: PCM instance
1702 * @params: the hw_params instance
1703 * @var: parameter to retrieve
1704 * @dir: pointer to the direction (-1,0,1) or %NULL
1706 * Inside configuration space defined by @params remove from @var all
1707 * values < maximum. Reduce configuration space accordingly.
1709 * Return: The maximum, or a negative error code on failure.
1711 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1712 struct snd_pcm_hw_params *params,
1713 snd_pcm_hw_param_t var, int *dir)
1715 int changed = _snd_pcm_hw_param_last(params, var);
1718 if (params->rmask) {
1719 int err = snd_pcm_hw_refine(pcm, params);
1723 return snd_pcm_hw_param_value(params, var, dir);
1726 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1729 * snd_pcm_hw_param_choose - choose a configuration defined by @params
1730 * @pcm: PCM instance
1731 * @params: the hw_params instance
1733 * Choose one configuration from configuration space defined by @params.
1734 * The configuration chosen is that obtained fixing in this order:
1735 * first access, first format, first subformat, min channels,
1736 * min rate, min period time, max buffer size, min tick time
1738 * Return: Zero if successful, or a negative error code on failure.
1740 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1741 struct snd_pcm_hw_params *params)
1743 static int vars[] = {
1744 SNDRV_PCM_HW_PARAM_ACCESS,
1745 SNDRV_PCM_HW_PARAM_FORMAT,
1746 SNDRV_PCM_HW_PARAM_SUBFORMAT,
1747 SNDRV_PCM_HW_PARAM_CHANNELS,
1748 SNDRV_PCM_HW_PARAM_RATE,
1749 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1750 SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1751 SNDRV_PCM_HW_PARAM_TICK_TIME,
1756 for (v = vars; *v != -1; v++) {
1757 if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1758 err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1760 err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1761 if (snd_BUG_ON(err < 0))
1767 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1770 struct snd_pcm_runtime *runtime = substream->runtime;
1771 unsigned long flags;
1772 snd_pcm_stream_lock_irqsave(substream, flags);
1773 if (snd_pcm_running(substream) &&
1774 snd_pcm_update_hw_ptr(substream) >= 0)
1775 runtime->status->hw_ptr %= runtime->buffer_size;
1777 runtime->status->hw_ptr = 0;
1778 runtime->hw_ptr_wrap = 0;
1780 snd_pcm_stream_unlock_irqrestore(substream, flags);
1784 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1787 struct snd_pcm_channel_info *info = arg;
1788 struct snd_pcm_runtime *runtime = substream->runtime;
1790 if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1794 width = snd_pcm_format_physical_width(runtime->format);
1798 switch (runtime->access) {
1799 case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1800 case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1801 info->first = info->channel * width;
1802 info->step = runtime->channels * width;
1804 case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1805 case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1807 size_t size = runtime->dma_bytes / runtime->channels;
1808 info->first = info->channel * size * 8;
1819 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1822 struct snd_pcm_hw_params *params = arg;
1823 snd_pcm_format_t format;
1827 params->fifo_size = substream->runtime->hw.fifo_size;
1828 if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1829 format = params_format(params);
1830 channels = params_channels(params);
1831 frame_size = snd_pcm_format_size(format, channels);
1833 params->fifo_size /= frame_size;
1839 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1840 * @substream: the pcm substream instance
1841 * @cmd: ioctl command
1842 * @arg: ioctl argument
1844 * Processes the generic ioctl commands for PCM.
1845 * Can be passed as the ioctl callback for PCM ops.
1847 * Return: Zero if successful, or a negative error code on failure.
1849 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1850 unsigned int cmd, void *arg)
1853 case SNDRV_PCM_IOCTL1_RESET:
1854 return snd_pcm_lib_ioctl_reset(substream, arg);
1855 case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1856 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1857 case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1858 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1863 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1866 * snd_pcm_period_elapsed - update the pcm status for the next period
1867 * @substream: the pcm substream instance
1869 * This function is called from the interrupt handler when the
1870 * PCM has processed the period size. It will update the current
1871 * pointer, wake up sleepers, etc.
1873 * Even if more than one periods have elapsed since the last call, you
1874 * have to call this only once.
1876 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1878 struct snd_pcm_runtime *runtime;
1879 unsigned long flags;
1881 if (snd_BUG_ON(!substream))
1884 snd_pcm_stream_lock_irqsave(substream, flags);
1885 if (PCM_RUNTIME_CHECK(substream))
1887 runtime = substream->runtime;
1889 if (!snd_pcm_running(substream) ||
1890 snd_pcm_update_hw_ptr0(substream, 1) < 0)
1893 #ifdef CONFIG_SND_PCM_TIMER
1894 if (substream->timer_running)
1895 snd_timer_interrupt(substream->timer, 1);
1898 kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1900 snd_pcm_stream_unlock_irqrestore(substream, flags);
1903 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1906 * Wait until avail_min data becomes available
1907 * Returns a negative error code if any error occurs during operation.
1908 * The available space is stored on availp. When err = 0 and avail = 0
1909 * on the capture stream, it indicates the stream is in DRAINING state.
1911 static int wait_for_avail(struct snd_pcm_substream *substream,
1912 snd_pcm_uframes_t *availp)
1914 struct snd_pcm_runtime *runtime = substream->runtime;
1915 int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1918 snd_pcm_uframes_t avail = 0;
1919 long wait_time, tout;
1921 init_waitqueue_entry(&wait, current);
1922 set_current_state(TASK_INTERRUPTIBLE);
1923 add_wait_queue(&runtime->tsleep, &wait);
1925 if (runtime->no_period_wakeup)
1926 wait_time = MAX_SCHEDULE_TIMEOUT;
1929 if (runtime->rate) {
1930 long t = runtime->period_size * 2 / runtime->rate;
1931 wait_time = max(t, wait_time);
1933 wait_time = msecs_to_jiffies(wait_time * 1000);
1937 if (signal_pending(current)) {
1943 * We need to check if space became available already
1944 * (and thus the wakeup happened already) first to close
1945 * the race of space already having become available.
1946 * This check must happen after been added to the waitqueue
1947 * and having current state be INTERRUPTIBLE.
1950 avail = snd_pcm_playback_avail(runtime);
1952 avail = snd_pcm_capture_avail(runtime);
1953 if (avail >= runtime->twake)
1955 snd_pcm_stream_unlock_irq(substream);
1957 tout = schedule_timeout(wait_time);
1959 snd_pcm_stream_lock_irq(substream);
1960 set_current_state(TASK_INTERRUPTIBLE);
1961 switch (runtime->status->state) {
1962 case SNDRV_PCM_STATE_SUSPENDED:
1965 case SNDRV_PCM_STATE_XRUN:
1968 case SNDRV_PCM_STATE_DRAINING:
1972 avail = 0; /* indicate draining */
1974 case SNDRV_PCM_STATE_OPEN:
1975 case SNDRV_PCM_STATE_SETUP:
1976 case SNDRV_PCM_STATE_DISCONNECTED:
1979 case SNDRV_PCM_STATE_PAUSED:
1983 pcm_dbg(substream->pcm,
1984 "%s write error (DMA or IRQ trouble?)\n",
1985 is_playback ? "playback" : "capture");
1991 set_current_state(TASK_RUNNING);
1992 remove_wait_queue(&runtime->tsleep, &wait);
1997 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1999 unsigned long data, unsigned int off,
2000 snd_pcm_uframes_t frames)
2002 struct snd_pcm_runtime *runtime = substream->runtime;
2004 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2005 if (substream->ops->copy) {
2006 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2009 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2010 if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
2016 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
2017 unsigned long data, unsigned int off,
2018 snd_pcm_uframes_t size);
2020 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
2022 snd_pcm_uframes_t size,
2024 transfer_f transfer)
2026 struct snd_pcm_runtime *runtime = substream->runtime;
2027 snd_pcm_uframes_t xfer = 0;
2028 snd_pcm_uframes_t offset = 0;
2029 snd_pcm_uframes_t avail;
2035 snd_pcm_stream_lock_irq(substream);
2036 switch (runtime->status->state) {
2037 case SNDRV_PCM_STATE_PREPARED:
2038 case SNDRV_PCM_STATE_RUNNING:
2039 case SNDRV_PCM_STATE_PAUSED:
2041 case SNDRV_PCM_STATE_XRUN:
2044 case SNDRV_PCM_STATE_SUSPENDED:
2052 runtime->twake = runtime->control->avail_min ? : 1;
2053 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2054 snd_pcm_update_hw_ptr(substream);
2055 avail = snd_pcm_playback_avail(runtime);
2057 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2058 snd_pcm_uframes_t cont;
2064 runtime->twake = min_t(snd_pcm_uframes_t, size,
2065 runtime->control->avail_min ? : 1);
2066 err = wait_for_avail(substream, &avail);
2070 frames = size > avail ? avail : size;
2071 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2074 if (snd_BUG_ON(!frames)) {
2076 snd_pcm_stream_unlock_irq(substream);
2079 appl_ptr = runtime->control->appl_ptr;
2080 appl_ofs = appl_ptr % runtime->buffer_size;
2081 snd_pcm_stream_unlock_irq(substream);
2082 err = transfer(substream, appl_ofs, data, offset, frames);
2083 snd_pcm_stream_lock_irq(substream);
2086 switch (runtime->status->state) {
2087 case SNDRV_PCM_STATE_XRUN:
2090 case SNDRV_PCM_STATE_SUSPENDED:
2097 if (appl_ptr >= runtime->boundary)
2098 appl_ptr -= runtime->boundary;
2099 runtime->control->appl_ptr = appl_ptr;
2100 if (substream->ops->ack)
2101 substream->ops->ack(substream);
2107 if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2108 snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2109 err = snd_pcm_start(substream);
2116 if (xfer > 0 && err >= 0)
2117 snd_pcm_update_state(substream, runtime);
2118 snd_pcm_stream_unlock_irq(substream);
2119 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2122 /* sanity-check for read/write methods */
2123 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2125 struct snd_pcm_runtime *runtime;
2126 if (PCM_RUNTIME_CHECK(substream))
2128 runtime = substream->runtime;
2129 if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
2131 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2136 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
2138 struct snd_pcm_runtime *runtime;
2142 err = pcm_sanity_check(substream);
2145 runtime = substream->runtime;
2146 nonblock = !!(substream->f_flags & O_NONBLOCK);
2148 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2149 runtime->channels > 1)
2151 return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
2152 snd_pcm_lib_write_transfer);
2155 EXPORT_SYMBOL(snd_pcm_lib_write);
2157 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
2159 unsigned long data, unsigned int off,
2160 snd_pcm_uframes_t frames)
2162 struct snd_pcm_runtime *runtime = substream->runtime;
2164 void __user **bufs = (void __user **)data;
2165 int channels = runtime->channels;
2167 if (substream->ops->copy) {
2168 if (snd_BUG_ON(!substream->ops->silence))
2170 for (c = 0; c < channels; ++c, ++bufs) {
2171 if (*bufs == NULL) {
2172 if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
2175 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2176 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2181 /* default transfer behaviour */
2182 size_t dma_csize = runtime->dma_bytes / channels;
2183 for (c = 0; c < channels; ++c, ++bufs) {
2184 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2185 if (*bufs == NULL) {
2186 snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
2188 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2189 if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
2197 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
2199 snd_pcm_uframes_t frames)
2201 struct snd_pcm_runtime *runtime;
2205 err = pcm_sanity_check(substream);
2208 runtime = substream->runtime;
2209 nonblock = !!(substream->f_flags & O_NONBLOCK);
2211 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2213 return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2214 nonblock, snd_pcm_lib_writev_transfer);
2217 EXPORT_SYMBOL(snd_pcm_lib_writev);
2219 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
2221 unsigned long data, unsigned int off,
2222 snd_pcm_uframes_t frames)
2224 struct snd_pcm_runtime *runtime = substream->runtime;
2226 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2227 if (substream->ops->copy) {
2228 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2231 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2232 if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2238 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2240 snd_pcm_uframes_t size,
2242 transfer_f transfer)
2244 struct snd_pcm_runtime *runtime = substream->runtime;
2245 snd_pcm_uframes_t xfer = 0;
2246 snd_pcm_uframes_t offset = 0;
2247 snd_pcm_uframes_t avail;
2253 snd_pcm_stream_lock_irq(substream);
2254 switch (runtime->status->state) {
2255 case SNDRV_PCM_STATE_PREPARED:
2256 if (size >= runtime->start_threshold) {
2257 err = snd_pcm_start(substream);
2262 case SNDRV_PCM_STATE_DRAINING:
2263 case SNDRV_PCM_STATE_RUNNING:
2264 case SNDRV_PCM_STATE_PAUSED:
2266 case SNDRV_PCM_STATE_XRUN:
2269 case SNDRV_PCM_STATE_SUSPENDED:
2277 runtime->twake = runtime->control->avail_min ? : 1;
2278 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2279 snd_pcm_update_hw_ptr(substream);
2280 avail = snd_pcm_capture_avail(runtime);
2282 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2283 snd_pcm_uframes_t cont;
2285 if (runtime->status->state ==
2286 SNDRV_PCM_STATE_DRAINING) {
2287 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2294 runtime->twake = min_t(snd_pcm_uframes_t, size,
2295 runtime->control->avail_min ? : 1);
2296 err = wait_for_avail(substream, &avail);
2300 continue; /* draining */
2302 frames = size > avail ? avail : size;
2303 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2306 if (snd_BUG_ON(!frames)) {
2308 snd_pcm_stream_unlock_irq(substream);
2311 appl_ptr = runtime->control->appl_ptr;
2312 appl_ofs = appl_ptr % runtime->buffer_size;
2313 snd_pcm_stream_unlock_irq(substream);
2314 err = transfer(substream, appl_ofs, data, offset, frames);
2315 snd_pcm_stream_lock_irq(substream);
2318 switch (runtime->status->state) {
2319 case SNDRV_PCM_STATE_XRUN:
2322 case SNDRV_PCM_STATE_SUSPENDED:
2329 if (appl_ptr >= runtime->boundary)
2330 appl_ptr -= runtime->boundary;
2331 runtime->control->appl_ptr = appl_ptr;
2332 if (substream->ops->ack)
2333 substream->ops->ack(substream);
2342 if (xfer > 0 && err >= 0)
2343 snd_pcm_update_state(substream, runtime);
2344 snd_pcm_stream_unlock_irq(substream);
2345 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2348 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2350 struct snd_pcm_runtime *runtime;
2354 err = pcm_sanity_check(substream);
2357 runtime = substream->runtime;
2358 nonblock = !!(substream->f_flags & O_NONBLOCK);
2359 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2361 return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2364 EXPORT_SYMBOL(snd_pcm_lib_read);
2366 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2368 unsigned long data, unsigned int off,
2369 snd_pcm_uframes_t frames)
2371 struct snd_pcm_runtime *runtime = substream->runtime;
2373 void __user **bufs = (void __user **)data;
2374 int channels = runtime->channels;
2376 if (substream->ops->copy) {
2377 for (c = 0; c < channels; ++c, ++bufs) {
2381 buf = *bufs + samples_to_bytes(runtime, off);
2382 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2386 snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2387 for (c = 0; c < channels; ++c, ++bufs) {
2393 hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2394 buf = *bufs + samples_to_bytes(runtime, off);
2395 if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2402 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2404 snd_pcm_uframes_t frames)
2406 struct snd_pcm_runtime *runtime;
2410 err = pcm_sanity_check(substream);
2413 runtime = substream->runtime;
2414 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2417 nonblock = !!(substream->f_flags & O_NONBLOCK);
2418 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2420 return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2423 EXPORT_SYMBOL(snd_pcm_lib_readv);
2426 * standard channel mapping helpers
2429 /* default channel maps for multi-channel playbacks, up to 8 channels */
2430 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2432 .map = { SNDRV_CHMAP_MONO } },
2434 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2436 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2437 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2439 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2440 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2441 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2443 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2444 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2445 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2446 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2449 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2451 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2452 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2454 .map = { SNDRV_CHMAP_MONO } },
2456 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2458 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2459 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2461 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2462 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2463 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2465 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2466 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2467 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2468 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2471 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2473 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2475 if (ch > info->max_channels)
2477 return !info->channel_mask || (info->channel_mask & (1U << ch));
2480 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2481 struct snd_ctl_elem_info *uinfo)
2483 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2485 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2487 uinfo->count = info->max_channels;
2488 uinfo->value.integer.min = 0;
2489 uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2493 /* get callback for channel map ctl element
2494 * stores the channel position firstly matching with the current channels
2496 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2497 struct snd_ctl_elem_value *ucontrol)
2499 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2500 unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2501 struct snd_pcm_substream *substream;
2502 const struct snd_pcm_chmap_elem *map;
2504 if (snd_BUG_ON(!info->chmap))
2506 substream = snd_pcm_chmap_substream(info, idx);
2509 memset(ucontrol->value.integer.value, 0,
2510 sizeof(ucontrol->value.integer.value));
2511 if (!substream->runtime)
2512 return 0; /* no channels set */
2513 for (map = info->chmap; map->channels; map++) {
2515 if (map->channels == substream->runtime->channels &&
2516 valid_chmap_channels(info, map->channels)) {
2517 for (i = 0; i < map->channels; i++)
2518 ucontrol->value.integer.value[i] = map->map[i];
2525 /* tlv callback for channel map ctl element
2526 * expands the pre-defined channel maps in a form of TLV
2528 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2529 unsigned int size, unsigned int __user *tlv)
2531 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2532 const struct snd_pcm_chmap_elem *map;
2533 unsigned int __user *dst;
2536 if (snd_BUG_ON(!info->chmap))
2540 if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2544 for (map = info->chmap; map->channels; map++) {
2545 int chs_bytes = map->channels * 4;
2546 if (!valid_chmap_channels(info, map->channels))
2550 if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2551 put_user(chs_bytes, dst + 1))
2556 if (size < chs_bytes)
2560 for (c = 0; c < map->channels; c++) {
2561 if (put_user(map->map[c], dst))
2566 if (put_user(count, tlv + 1))
2571 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2573 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2574 info->pcm->streams[info->stream].chmap_kctl = NULL;
2579 * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2580 * @pcm: the assigned PCM instance
2581 * @stream: stream direction
2582 * @chmap: channel map elements (for query)
2583 * @max_channels: the max number of channels for the stream
2584 * @private_value: the value passed to each kcontrol's private_value field
2585 * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2587 * Create channel-mapping control elements assigned to the given PCM stream(s).
2588 * Return: Zero if successful, or a negative error value.
2590 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2591 const struct snd_pcm_chmap_elem *chmap,
2593 unsigned long private_value,
2594 struct snd_pcm_chmap **info_ret)
2596 struct snd_pcm_chmap *info;
2597 struct snd_kcontrol_new knew = {
2598 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
2599 .access = SNDRV_CTL_ELEM_ACCESS_READ |
2600 SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2601 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2602 .info = pcm_chmap_ctl_info,
2603 .get = pcm_chmap_ctl_get,
2604 .tlv.c = pcm_chmap_ctl_tlv,
2608 info = kzalloc(sizeof(*info), GFP_KERNEL);
2612 info->stream = stream;
2613 info->chmap = chmap;
2614 info->max_channels = max_channels;
2615 if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2616 knew.name = "Playback Channel Map";
2618 knew.name = "Capture Channel Map";
2619 knew.device = pcm->device;
2620 knew.count = pcm->streams[stream].substream_count;
2621 knew.private_value = private_value;
2622 info->kctl = snd_ctl_new1(&knew, info);
2627 info->kctl->private_free = pcm_chmap_ctl_private_free;
2628 err = snd_ctl_add(pcm->card, info->kctl);
2631 pcm->streams[stream].chmap_kctl = info->kctl;
2636 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);