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 <sound/core.h>
27 #include <sound/control.h>
28 #include <sound/info.h>
29 #include <sound/pcm.h>
30 #include <sound/pcm_params.h>
31 #include <sound/timer.h>
34 * fill ring buffer with silence
35 * runtime->silence_start: starting pointer to silence area
36 * runtime->silence_filled: size filled with silence
37 * runtime->silence_threshold: threshold from application
38 * runtime->silence_size: maximal size from application
40 * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
42 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
44 struct snd_pcm_runtime *runtime = substream->runtime;
45 snd_pcm_uframes_t frames, ofs, transfer;
47 if (runtime->silence_size < runtime->boundary) {
48 snd_pcm_sframes_t noise_dist, n;
49 if (runtime->silence_start != runtime->control->appl_ptr) {
50 n = runtime->control->appl_ptr - runtime->silence_start;
52 n += runtime->boundary;
53 if ((snd_pcm_uframes_t)n < runtime->silence_filled)
54 runtime->silence_filled -= n;
56 runtime->silence_filled = 0;
57 runtime->silence_start = runtime->control->appl_ptr;
59 if (runtime->silence_filled >= runtime->buffer_size)
61 noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
62 if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
64 frames = runtime->silence_threshold - noise_dist;
65 if (frames > runtime->silence_size)
66 frames = runtime->silence_size;
68 if (new_hw_ptr == ULONG_MAX) { /* initialization */
69 snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
70 if (avail > runtime->buffer_size)
71 avail = runtime->buffer_size;
72 runtime->silence_filled = avail > 0 ? avail : 0;
73 runtime->silence_start = (runtime->status->hw_ptr +
74 runtime->silence_filled) %
77 ofs = runtime->status->hw_ptr;
78 frames = new_hw_ptr - ofs;
79 if ((snd_pcm_sframes_t)frames < 0)
80 frames += runtime->boundary;
81 runtime->silence_filled -= frames;
82 if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
83 runtime->silence_filled = 0;
84 runtime->silence_start = new_hw_ptr;
86 runtime->silence_start = ofs;
89 frames = runtime->buffer_size - runtime->silence_filled;
91 if (snd_BUG_ON(frames > runtime->buffer_size))
95 ofs = runtime->silence_start % runtime->buffer_size;
97 transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
98 if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
99 runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
100 if (substream->ops->silence) {
102 err = substream->ops->silence(substream, -1, ofs, transfer);
105 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
106 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
110 unsigned int channels = runtime->channels;
111 if (substream->ops->silence) {
112 for (c = 0; c < channels; ++c) {
114 err = substream->ops->silence(substream, c, ofs, transfer);
118 size_t dma_csize = runtime->dma_bytes / channels;
119 for (c = 0; c < channels; ++c) {
120 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
121 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
125 runtime->silence_filled += transfer;
131 static void pcm_debug_name(struct snd_pcm_substream *substream,
132 char *name, size_t len)
134 snprintf(name, len, "pcmC%dD%d%c:%d",
135 substream->pcm->card->number,
136 substream->pcm->device,
137 substream->stream ? 'c' : 'p',
141 #define XRUN_DEBUG_BASIC (1<<0)
142 #define XRUN_DEBUG_STACK (1<<1) /* dump also stack */
143 #define XRUN_DEBUG_JIFFIESCHECK (1<<2) /* do jiffies check */
144 #define XRUN_DEBUG_PERIODUPDATE (1<<3) /* full period update info */
145 #define XRUN_DEBUG_HWPTRUPDATE (1<<4) /* full hwptr update info */
146 #define XRUN_DEBUG_LOG (1<<5) /* show last 10 positions on err */
147 #define XRUN_DEBUG_LOGONCE (1<<6) /* do above only once */
149 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
151 #define xrun_debug(substream, mask) \
152 ((substream)->pstr->xrun_debug & (mask))
154 #define xrun_debug(substream, mask) 0
157 #define dump_stack_on_xrun(substream) do { \
158 if (xrun_debug(substream, XRUN_DEBUG_STACK)) \
162 static void xrun(struct snd_pcm_substream *substream)
164 struct snd_pcm_runtime *runtime = substream->runtime;
166 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
167 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
168 snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
169 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
171 pcm_debug_name(substream, name, sizeof(name));
172 snd_printd(KERN_DEBUG "XRUN: %s\n", name);
173 dump_stack_on_xrun(substream);
177 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
178 #define hw_ptr_error(substream, fmt, args...) \
180 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) { \
181 xrun_log_show(substream); \
182 if (printk_ratelimit()) { \
183 snd_printd("PCM: " fmt, ##args); \
185 dump_stack_on_xrun(substream); \
189 #define XRUN_LOG_CNT 10
191 struct hwptr_log_entry {
192 unsigned long jiffies;
193 snd_pcm_uframes_t pos;
194 snd_pcm_uframes_t period_size;
195 snd_pcm_uframes_t buffer_size;
196 snd_pcm_uframes_t old_hw_ptr;
197 snd_pcm_uframes_t hw_ptr_base;
200 struct snd_pcm_hwptr_log {
203 struct hwptr_log_entry entries[XRUN_LOG_CNT];
206 static void xrun_log(struct snd_pcm_substream *substream,
207 snd_pcm_uframes_t pos)
209 struct snd_pcm_runtime *runtime = substream->runtime;
210 struct snd_pcm_hwptr_log *log = runtime->hwptr_log;
211 struct hwptr_log_entry *entry;
214 log = kzalloc(sizeof(*log), GFP_ATOMIC);
217 runtime->hwptr_log = log;
219 if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
222 entry = &log->entries[log->idx];
223 entry->jiffies = jiffies;
225 entry->period_size = runtime->period_size;
226 entry->buffer_size = runtime->buffer_size;
227 entry->old_hw_ptr = runtime->status->hw_ptr;
228 entry->hw_ptr_base = runtime->hw_ptr_base;
229 log->idx = (log->idx + 1) % XRUN_LOG_CNT;
232 static void xrun_log_show(struct snd_pcm_substream *substream)
234 struct snd_pcm_hwptr_log *log = substream->runtime->hwptr_log;
235 struct hwptr_log_entry *entry;
242 if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
244 pcm_debug_name(substream, name, sizeof(name));
245 for (cnt = 0, idx = log->idx; cnt < XRUN_LOG_CNT; cnt++) {
246 entry = &log->entries[idx];
247 if (entry->period_size == 0)
249 snd_printd("hwptr log: %s: j=%lu, pos=%ld/%ld/%ld, "
251 name, entry->jiffies, (unsigned long)entry->pos,
252 (unsigned long)entry->period_size,
253 (unsigned long)entry->buffer_size,
254 (unsigned long)entry->old_hw_ptr,
255 (unsigned long)entry->hw_ptr_base);
262 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
264 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
265 #define xrun_log(substream, pos) do { } while (0)
266 #define xrun_log_show(substream) do { } while (0)
270 int snd_pcm_update_state(struct snd_pcm_substream *substream,
271 struct snd_pcm_runtime *runtime)
273 snd_pcm_uframes_t avail;
275 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
276 avail = snd_pcm_playback_avail(runtime);
278 avail = snd_pcm_capture_avail(runtime);
279 if (avail > runtime->avail_max)
280 runtime->avail_max = avail;
281 if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
282 if (avail >= runtime->buffer_size) {
283 snd_pcm_drain_done(substream);
287 if (avail >= runtime->stop_threshold) {
292 if (runtime->twake) {
293 if (avail >= runtime->twake)
294 wake_up(&runtime->tsleep);
295 } else if (avail >= runtime->control->avail_min)
296 wake_up(&runtime->sleep);
300 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
301 unsigned int in_interrupt)
303 struct snd_pcm_runtime *runtime = substream->runtime;
304 snd_pcm_uframes_t pos;
305 snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
306 snd_pcm_sframes_t hdelta, delta;
307 unsigned long jdelta;
309 old_hw_ptr = runtime->status->hw_ptr;
310 pos = substream->ops->pointer(substream);
311 if (pos == SNDRV_PCM_POS_XRUN) {
315 if (pos >= runtime->buffer_size) {
316 if (printk_ratelimit()) {
318 pcm_debug_name(substream, name, sizeof(name));
319 xrun_log_show(substream);
320 snd_printd(KERN_ERR "BUG: %s, pos = %ld, "
321 "buffer size = %ld, period size = %ld\n",
322 name, pos, runtime->buffer_size,
323 runtime->period_size);
327 pos -= pos % runtime->min_align;
328 if (xrun_debug(substream, XRUN_DEBUG_LOG))
329 xrun_log(substream, pos);
330 hw_base = runtime->hw_ptr_base;
331 new_hw_ptr = hw_base + pos;
333 /* we know that one period was processed */
334 /* delta = "expected next hw_ptr" for in_interrupt != 0 */
335 delta = runtime->hw_ptr_interrupt + runtime->period_size;
336 if (delta > new_hw_ptr) {
337 /* check for double acknowledged interrupts */
338 hdelta = jiffies - runtime->hw_ptr_jiffies;
339 if (hdelta > runtime->hw_ptr_buffer_jiffies/2) {
340 hw_base += runtime->buffer_size;
341 if (hw_base >= runtime->boundary)
343 new_hw_ptr = hw_base + pos;
348 /* new_hw_ptr might be lower than old_hw_ptr in case when */
349 /* pointer crosses the end of the ring buffer */
350 if (new_hw_ptr < old_hw_ptr) {
351 hw_base += runtime->buffer_size;
352 if (hw_base >= runtime->boundary)
354 new_hw_ptr = hw_base + pos;
357 delta = new_hw_ptr - old_hw_ptr;
359 delta += runtime->boundary;
360 if (xrun_debug(substream, in_interrupt ?
361 XRUN_DEBUG_PERIODUPDATE : XRUN_DEBUG_HWPTRUPDATE)) {
363 pcm_debug_name(substream, name, sizeof(name));
364 snd_printd("%s_update: %s: pos=%u/%u/%u, "
365 "hwptr=%ld/%ld/%ld/%ld\n",
366 in_interrupt ? "period" : "hwptr",
369 (unsigned int)runtime->period_size,
370 (unsigned int)runtime->buffer_size,
371 (unsigned long)delta,
372 (unsigned long)old_hw_ptr,
373 (unsigned long)new_hw_ptr,
374 (unsigned long)runtime->hw_ptr_base);
377 /* without period interrupts, there are no regular pointer updates */
378 if (runtime->no_period_wakeup)
381 /* something must be really wrong */
382 if (delta >= runtime->buffer_size + runtime->period_size) {
383 hw_ptr_error(substream,
384 "Unexpected hw_pointer value %s"
385 "(stream=%i, pos=%ld, new_hw_ptr=%ld, "
387 in_interrupt ? "[Q] " : "[P]",
388 substream->stream, (long)pos,
389 (long)new_hw_ptr, (long)old_hw_ptr);
393 /* Do jiffies check only in xrun_debug mode */
394 if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
395 goto no_jiffies_check;
397 /* Skip the jiffies check for hardwares with BATCH flag.
398 * Such hardware usually just increases the position at each IRQ,
399 * thus it can't give any strange position.
401 if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
402 goto no_jiffies_check;
404 if (hdelta < runtime->delay)
405 goto no_jiffies_check;
406 hdelta -= runtime->delay;
407 jdelta = jiffies - runtime->hw_ptr_jiffies;
408 if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
410 (((runtime->period_size * HZ) / runtime->rate)
412 /* move new_hw_ptr according jiffies not pos variable */
413 new_hw_ptr = old_hw_ptr;
415 /* use loop to avoid checks for delta overflows */
416 /* the delta value is small or zero in most cases */
418 new_hw_ptr += runtime->period_size;
419 if (new_hw_ptr >= runtime->boundary)
420 new_hw_ptr -= runtime->boundary;
423 /* align hw_base to buffer_size */
424 hw_ptr_error(substream,
425 "hw_ptr skipping! %s"
426 "(pos=%ld, delta=%ld, period=%ld, "
427 "jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
428 in_interrupt ? "[Q] " : "",
429 (long)pos, (long)hdelta,
430 (long)runtime->period_size, jdelta,
431 ((hdelta * HZ) / runtime->rate), hw_base,
432 (unsigned long)old_hw_ptr,
433 (unsigned long)new_hw_ptr);
434 /* reset values to proper state */
436 hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
439 if (delta > runtime->period_size + runtime->period_size / 2) {
440 hw_ptr_error(substream,
441 "Lost interrupts? %s"
442 "(stream=%i, delta=%ld, new_hw_ptr=%ld, "
444 in_interrupt ? "[Q] " : "",
445 substream->stream, (long)delta,
451 if (runtime->status->hw_ptr == new_hw_ptr)
454 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
455 runtime->silence_size > 0)
456 snd_pcm_playback_silence(substream, new_hw_ptr);
459 delta = new_hw_ptr - runtime->hw_ptr_interrupt;
461 delta += runtime->boundary;
462 delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
463 runtime->hw_ptr_interrupt += delta;
464 if (runtime->hw_ptr_interrupt >= runtime->boundary)
465 runtime->hw_ptr_interrupt -= runtime->boundary;
467 runtime->hw_ptr_base = hw_base;
468 runtime->status->hw_ptr = new_hw_ptr;
469 runtime->hw_ptr_jiffies = jiffies;
470 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
471 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
473 return snd_pcm_update_state(substream, runtime);
476 /* CAUTION: call it with irq disabled */
477 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
479 return snd_pcm_update_hw_ptr0(substream, 0);
483 * snd_pcm_set_ops - set the PCM operators
484 * @pcm: the pcm instance
485 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
486 * @ops: the operator table
488 * Sets the given PCM operators to the pcm instance.
490 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction, struct snd_pcm_ops *ops)
492 struct snd_pcm_str *stream = &pcm->streams[direction];
493 struct snd_pcm_substream *substream;
495 for (substream = stream->substream; substream != NULL; substream = substream->next)
496 substream->ops = ops;
499 EXPORT_SYMBOL(snd_pcm_set_ops);
502 * snd_pcm_sync - set the PCM sync id
503 * @substream: the pcm substream
505 * Sets the PCM sync identifier for the card.
507 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
509 struct snd_pcm_runtime *runtime = substream->runtime;
511 runtime->sync.id32[0] = substream->pcm->card->number;
512 runtime->sync.id32[1] = -1;
513 runtime->sync.id32[2] = -1;
514 runtime->sync.id32[3] = -1;
517 EXPORT_SYMBOL(snd_pcm_set_sync);
520 * Standard ioctl routine
523 static inline unsigned int div32(unsigned int a, unsigned int b,
534 static inline unsigned int div_down(unsigned int a, unsigned int b)
541 static inline unsigned int div_up(unsigned int a, unsigned int b)
553 static inline unsigned int mul(unsigned int a, unsigned int b)
557 if (div_down(UINT_MAX, a) < b)
562 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
563 unsigned int c, unsigned int *r)
565 u_int64_t n = (u_int64_t) a * b;
571 n = div_u64_rem(n, c, r);
580 * snd_interval_refine - refine the interval value of configurator
581 * @i: the interval value to refine
582 * @v: the interval value to refer to
584 * Refines the interval value with the reference value.
585 * The interval is changed to the range satisfying both intervals.
586 * The interval status (min, max, integer, etc.) are evaluated.
588 * Returns non-zero if the value is changed, zero if not changed.
590 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
593 if (snd_BUG_ON(snd_interval_empty(i)))
595 if (i->min < v->min) {
597 i->openmin = v->openmin;
599 } else if (i->min == v->min && !i->openmin && v->openmin) {
603 if (i->max > v->max) {
605 i->openmax = v->openmax;
607 } else if (i->max == v->max && !i->openmax && v->openmax) {
611 if (!i->integer && v->integer) {
624 } else if (!i->openmin && !i->openmax && i->min == i->max)
626 if (snd_interval_checkempty(i)) {
627 snd_interval_none(i);
633 EXPORT_SYMBOL(snd_interval_refine);
635 static int snd_interval_refine_first(struct snd_interval *i)
637 if (snd_BUG_ON(snd_interval_empty(i)))
639 if (snd_interval_single(i))
642 i->openmax = i->openmin;
648 static int snd_interval_refine_last(struct snd_interval *i)
650 if (snd_BUG_ON(snd_interval_empty(i)))
652 if (snd_interval_single(i))
655 i->openmin = i->openmax;
661 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
663 if (a->empty || b->empty) {
664 snd_interval_none(c);
668 c->min = mul(a->min, b->min);
669 c->openmin = (a->openmin || b->openmin);
670 c->max = mul(a->max, b->max);
671 c->openmax = (a->openmax || b->openmax);
672 c->integer = (a->integer && b->integer);
676 * snd_interval_div - refine the interval value with division
683 * Returns non-zero if the value is changed, zero if not changed.
685 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
688 if (a->empty || b->empty) {
689 snd_interval_none(c);
693 c->min = div32(a->min, b->max, &r);
694 c->openmin = (r || a->openmin || b->openmax);
696 c->max = div32(a->max, b->min, &r);
701 c->openmax = (a->openmax || b->openmin);
710 * snd_interval_muldivk - refine the interval value
713 * @k: divisor (as integer)
718 * Returns non-zero if the value is changed, zero if not changed.
720 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
721 unsigned int k, struct snd_interval *c)
724 if (a->empty || b->empty) {
725 snd_interval_none(c);
729 c->min = muldiv32(a->min, b->min, k, &r);
730 c->openmin = (r || a->openmin || b->openmin);
731 c->max = muldiv32(a->max, b->max, k, &r);
736 c->openmax = (a->openmax || b->openmax);
741 * snd_interval_mulkdiv - refine the interval value
743 * @k: dividend 2 (as integer)
749 * Returns non-zero if the value is changed, zero if not changed.
751 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
752 const struct snd_interval *b, struct snd_interval *c)
755 if (a->empty || b->empty) {
756 snd_interval_none(c);
760 c->min = muldiv32(a->min, k, b->max, &r);
761 c->openmin = (r || a->openmin || b->openmax);
763 c->max = muldiv32(a->max, k, b->min, &r);
768 c->openmax = (a->openmax || b->openmin);
780 * snd_interval_ratnum - refine the interval value
781 * @i: interval to refine
782 * @rats_count: number of ratnum_t
783 * @rats: ratnum_t array
784 * @nump: pointer to store the resultant numerator
785 * @denp: pointer to store the resultant denominator
787 * Returns non-zero if the value is changed, zero if not changed.
789 int snd_interval_ratnum(struct snd_interval *i,
790 unsigned int rats_count, struct snd_ratnum *rats,
791 unsigned int *nump, unsigned int *denp)
793 unsigned int best_num, best_den;
796 struct snd_interval t;
798 unsigned int result_num, result_den;
801 best_num = best_den = best_diff = 0;
802 for (k = 0; k < rats_count; ++k) {
803 unsigned int num = rats[k].num;
805 unsigned int q = i->min;
809 den = div_up(num, q);
810 if (den < rats[k].den_min)
812 if (den > rats[k].den_max)
813 den = rats[k].den_max;
816 r = (den - rats[k].den_min) % rats[k].den_step;
820 diff = num - q * den;
824 diff * best_den < best_diff * den) {
834 t.min = div_down(best_num, best_den);
835 t.openmin = !!(best_num % best_den);
837 result_num = best_num;
838 result_diff = best_diff;
839 result_den = best_den;
840 best_num = best_den = best_diff = 0;
841 for (k = 0; k < rats_count; ++k) {
842 unsigned int num = rats[k].num;
844 unsigned int q = i->max;
850 den = div_down(num, q);
851 if (den > rats[k].den_max)
853 if (den < rats[k].den_min)
854 den = rats[k].den_min;
857 r = (den - rats[k].den_min) % rats[k].den_step;
859 den += rats[k].den_step - r;
861 diff = q * den - num;
865 diff * best_den < best_diff * den) {
875 t.max = div_up(best_num, best_den);
876 t.openmax = !!(best_num % best_den);
878 err = snd_interval_refine(i, &t);
882 if (snd_interval_single(i)) {
883 if (best_diff * result_den < result_diff * best_den) {
884 result_num = best_num;
885 result_den = best_den;
895 EXPORT_SYMBOL(snd_interval_ratnum);
898 * snd_interval_ratden - refine the interval value
899 * @i: interval to refine
900 * @rats_count: number of struct ratden
901 * @rats: struct ratden array
902 * @nump: pointer to store the resultant numerator
903 * @denp: pointer to store the resultant denominator
905 * Returns non-zero if the value is changed, zero if not changed.
907 static int snd_interval_ratden(struct snd_interval *i,
908 unsigned int rats_count, struct snd_ratden *rats,
909 unsigned int *nump, unsigned int *denp)
911 unsigned int best_num, best_diff, best_den;
913 struct snd_interval t;
916 best_num = best_den = best_diff = 0;
917 for (k = 0; k < rats_count; ++k) {
919 unsigned int den = rats[k].den;
920 unsigned int q = i->min;
923 if (num > rats[k].num_max)
925 if (num < rats[k].num_min)
926 num = rats[k].num_max;
929 r = (num - rats[k].num_min) % rats[k].num_step;
931 num += rats[k].num_step - r;
933 diff = num - q * den;
935 diff * best_den < best_diff * den) {
945 t.min = div_down(best_num, best_den);
946 t.openmin = !!(best_num % best_den);
948 best_num = best_den = best_diff = 0;
949 for (k = 0; k < rats_count; ++k) {
951 unsigned int den = rats[k].den;
952 unsigned int q = i->max;
955 if (num < rats[k].num_min)
957 if (num > rats[k].num_max)
958 num = rats[k].num_max;
961 r = (num - rats[k].num_min) % rats[k].num_step;
965 diff = q * den - num;
967 diff * best_den < best_diff * den) {
977 t.max = div_up(best_num, best_den);
978 t.openmax = !!(best_num % best_den);
980 err = snd_interval_refine(i, &t);
984 if (snd_interval_single(i)) {
994 * snd_interval_list - refine the interval value from the list
995 * @i: the interval value to refine
996 * @count: the number of elements in the list
997 * @list: the value list
998 * @mask: the bit-mask to evaluate
1000 * Refines the interval value from the list.
1001 * When mask is non-zero, only the elements corresponding to bit 1 are
1004 * Returns non-zero if the value is changed, zero if not changed.
1006 int snd_interval_list(struct snd_interval *i, unsigned int count, unsigned int *list, unsigned int mask)
1009 struct snd_interval list_range;
1015 snd_interval_any(&list_range);
1016 list_range.min = UINT_MAX;
1018 for (k = 0; k < count; k++) {
1019 if (mask && !(mask & (1 << k)))
1021 if (!snd_interval_test(i, list[k]))
1023 list_range.min = min(list_range.min, list[k]);
1024 list_range.max = max(list_range.max, list[k]);
1026 return snd_interval_refine(i, &list_range);
1029 EXPORT_SYMBOL(snd_interval_list);
1031 static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
1035 n = (i->min - min) % step;
1036 if (n != 0 || i->openmin) {
1040 n = (i->max - min) % step;
1041 if (n != 0 || i->openmax) {
1045 if (snd_interval_checkempty(i)) {
1052 /* Info constraints helpers */
1055 * snd_pcm_hw_rule_add - add the hw-constraint rule
1056 * @runtime: the pcm runtime instance
1057 * @cond: condition bits
1058 * @var: the variable to evaluate
1059 * @func: the evaluation function
1060 * @private: the private data pointer passed to function
1061 * @dep: the dependent variables
1063 * Returns zero if successful, or a negative error code on failure.
1065 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1067 snd_pcm_hw_rule_func_t func, void *private,
1070 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1071 struct snd_pcm_hw_rule *c;
1074 va_start(args, dep);
1075 if (constrs->rules_num >= constrs->rules_all) {
1076 struct snd_pcm_hw_rule *new;
1077 unsigned int new_rules = constrs->rules_all + 16;
1078 new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1081 if (constrs->rules) {
1082 memcpy(new, constrs->rules,
1083 constrs->rules_num * sizeof(*c));
1084 kfree(constrs->rules);
1086 constrs->rules = new;
1087 constrs->rules_all = new_rules;
1089 c = &constrs->rules[constrs->rules_num];
1093 c->private = private;
1096 if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps)))
1101 dep = va_arg(args, int);
1103 constrs->rules_num++;
1108 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1111 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1112 * @runtime: PCM runtime instance
1113 * @var: hw_params variable to apply the mask
1114 * @mask: the bitmap mask
1116 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1118 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1121 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1122 struct snd_mask *maskp = constrs_mask(constrs, var);
1123 *maskp->bits &= mask;
1124 memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1125 if (*maskp->bits == 0)
1131 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1132 * @runtime: PCM runtime instance
1133 * @var: hw_params variable to apply the mask
1134 * @mask: the 64bit bitmap mask
1136 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1138 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1141 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1142 struct snd_mask *maskp = constrs_mask(constrs, var);
1143 maskp->bits[0] &= (u_int32_t)mask;
1144 maskp->bits[1] &= (u_int32_t)(mask >> 32);
1145 memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1146 if (! maskp->bits[0] && ! maskp->bits[1])
1152 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1153 * @runtime: PCM runtime instance
1154 * @var: hw_params variable to apply the integer constraint
1156 * Apply the constraint of integer to an interval parameter.
1158 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1160 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1161 return snd_interval_setinteger(constrs_interval(constrs, var));
1164 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1167 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1168 * @runtime: PCM runtime instance
1169 * @var: hw_params variable to apply the range
1170 * @min: the minimal value
1171 * @max: the maximal value
1173 * Apply the min/max range constraint to an interval parameter.
1175 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1176 unsigned int min, unsigned int max)
1178 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1179 struct snd_interval t;
1182 t.openmin = t.openmax = 0;
1184 return snd_interval_refine(constrs_interval(constrs, var), &t);
1187 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1189 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1190 struct snd_pcm_hw_rule *rule)
1192 struct snd_pcm_hw_constraint_list *list = rule->private;
1193 return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1198 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1199 * @runtime: PCM runtime instance
1200 * @cond: condition bits
1201 * @var: hw_params variable to apply the list constraint
1204 * Apply the list of constraints to an interval parameter.
1206 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1208 snd_pcm_hw_param_t var,
1209 struct snd_pcm_hw_constraint_list *l)
1211 return snd_pcm_hw_rule_add(runtime, cond, var,
1212 snd_pcm_hw_rule_list, l,
1216 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1218 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1219 struct snd_pcm_hw_rule *rule)
1221 struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1222 unsigned int num = 0, den = 0;
1224 err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1225 r->nrats, r->rats, &num, &den);
1226 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1227 params->rate_num = num;
1228 params->rate_den = den;
1234 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1235 * @runtime: PCM runtime instance
1236 * @cond: condition bits
1237 * @var: hw_params variable to apply the ratnums constraint
1238 * @r: struct snd_ratnums constriants
1240 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1242 snd_pcm_hw_param_t var,
1243 struct snd_pcm_hw_constraint_ratnums *r)
1245 return snd_pcm_hw_rule_add(runtime, cond, var,
1246 snd_pcm_hw_rule_ratnums, r,
1250 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1252 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1253 struct snd_pcm_hw_rule *rule)
1255 struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1256 unsigned int num = 0, den = 0;
1257 int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1258 r->nrats, r->rats, &num, &den);
1259 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1260 params->rate_num = num;
1261 params->rate_den = den;
1267 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1268 * @runtime: PCM runtime instance
1269 * @cond: condition bits
1270 * @var: hw_params variable to apply the ratdens constraint
1271 * @r: struct snd_ratdens constriants
1273 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1275 snd_pcm_hw_param_t var,
1276 struct snd_pcm_hw_constraint_ratdens *r)
1278 return snd_pcm_hw_rule_add(runtime, cond, var,
1279 snd_pcm_hw_rule_ratdens, r,
1283 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1285 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1286 struct snd_pcm_hw_rule *rule)
1288 unsigned int l = (unsigned long) rule->private;
1289 int width = l & 0xffff;
1290 unsigned int msbits = l >> 16;
1291 struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1292 if (snd_interval_single(i) && snd_interval_value(i) == width)
1293 params->msbits = msbits;
1298 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1299 * @runtime: PCM runtime instance
1300 * @cond: condition bits
1301 * @width: sample bits width
1302 * @msbits: msbits width
1304 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1307 unsigned int msbits)
1309 unsigned long l = (msbits << 16) | width;
1310 return snd_pcm_hw_rule_add(runtime, cond, -1,
1311 snd_pcm_hw_rule_msbits,
1313 SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1316 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1318 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1319 struct snd_pcm_hw_rule *rule)
1321 unsigned long step = (unsigned long) rule->private;
1322 return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1326 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1327 * @runtime: PCM runtime instance
1328 * @cond: condition bits
1329 * @var: hw_params variable to apply the step constraint
1332 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1334 snd_pcm_hw_param_t var,
1337 return snd_pcm_hw_rule_add(runtime, cond, var,
1338 snd_pcm_hw_rule_step, (void *) step,
1342 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1344 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1346 static unsigned int pow2_sizes[] = {
1347 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1348 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1349 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1350 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1352 return snd_interval_list(hw_param_interval(params, rule->var),
1353 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1357 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1358 * @runtime: PCM runtime instance
1359 * @cond: condition bits
1360 * @var: hw_params variable to apply the power-of-2 constraint
1362 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1364 snd_pcm_hw_param_t var)
1366 return snd_pcm_hw_rule_add(runtime, cond, var,
1367 snd_pcm_hw_rule_pow2, NULL,
1371 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1373 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1374 snd_pcm_hw_param_t var)
1376 if (hw_is_mask(var)) {
1377 snd_mask_any(hw_param_mask(params, var));
1378 params->cmask |= 1 << var;
1379 params->rmask |= 1 << var;
1382 if (hw_is_interval(var)) {
1383 snd_interval_any(hw_param_interval(params, var));
1384 params->cmask |= 1 << var;
1385 params->rmask |= 1 << var;
1391 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1394 memset(params, 0, sizeof(*params));
1395 for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1396 _snd_pcm_hw_param_any(params, k);
1397 for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1398 _snd_pcm_hw_param_any(params, k);
1402 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1405 * snd_pcm_hw_param_value - return @params field @var value
1406 * @params: the hw_params instance
1407 * @var: parameter to retrieve
1408 * @dir: pointer to the direction (-1,0,1) or %NULL
1410 * Return the value for field @var if it's fixed in configuration space
1411 * defined by @params. Return -%EINVAL otherwise.
1413 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1414 snd_pcm_hw_param_t var, int *dir)
1416 if (hw_is_mask(var)) {
1417 const struct snd_mask *mask = hw_param_mask_c(params, var);
1418 if (!snd_mask_single(mask))
1422 return snd_mask_value(mask);
1424 if (hw_is_interval(var)) {
1425 const struct snd_interval *i = hw_param_interval_c(params, var);
1426 if (!snd_interval_single(i))
1430 return snd_interval_value(i);
1435 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1437 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1438 snd_pcm_hw_param_t var)
1440 if (hw_is_mask(var)) {
1441 snd_mask_none(hw_param_mask(params, var));
1442 params->cmask |= 1 << var;
1443 params->rmask |= 1 << var;
1444 } else if (hw_is_interval(var)) {
1445 snd_interval_none(hw_param_interval(params, var));
1446 params->cmask |= 1 << var;
1447 params->rmask |= 1 << var;
1453 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1455 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1456 snd_pcm_hw_param_t var)
1459 if (hw_is_mask(var))
1460 changed = snd_mask_refine_first(hw_param_mask(params, var));
1461 else if (hw_is_interval(var))
1462 changed = snd_interval_refine_first(hw_param_interval(params, var));
1466 params->cmask |= 1 << var;
1467 params->rmask |= 1 << var;
1474 * snd_pcm_hw_param_first - refine config space and return minimum value
1475 * @pcm: PCM instance
1476 * @params: the hw_params instance
1477 * @var: parameter to retrieve
1478 * @dir: pointer to the direction (-1,0,1) or %NULL
1480 * Inside configuration space defined by @params remove from @var all
1481 * values > minimum. Reduce configuration space accordingly.
1482 * Return the minimum.
1484 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1485 struct snd_pcm_hw_params *params,
1486 snd_pcm_hw_param_t var, int *dir)
1488 int changed = _snd_pcm_hw_param_first(params, var);
1491 if (params->rmask) {
1492 int err = snd_pcm_hw_refine(pcm, params);
1493 if (snd_BUG_ON(err < 0))
1496 return snd_pcm_hw_param_value(params, var, dir);
1499 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1501 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1502 snd_pcm_hw_param_t var)
1505 if (hw_is_mask(var))
1506 changed = snd_mask_refine_last(hw_param_mask(params, var));
1507 else if (hw_is_interval(var))
1508 changed = snd_interval_refine_last(hw_param_interval(params, var));
1512 params->cmask |= 1 << var;
1513 params->rmask |= 1 << var;
1520 * snd_pcm_hw_param_last - refine config space and return maximum value
1521 * @pcm: PCM instance
1522 * @params: the hw_params instance
1523 * @var: parameter to retrieve
1524 * @dir: pointer to the direction (-1,0,1) or %NULL
1526 * Inside configuration space defined by @params remove from @var all
1527 * values < maximum. Reduce configuration space accordingly.
1528 * Return the maximum.
1530 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1531 struct snd_pcm_hw_params *params,
1532 snd_pcm_hw_param_t var, int *dir)
1534 int changed = _snd_pcm_hw_param_last(params, var);
1537 if (params->rmask) {
1538 int err = snd_pcm_hw_refine(pcm, params);
1539 if (snd_BUG_ON(err < 0))
1542 return snd_pcm_hw_param_value(params, var, dir);
1545 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1548 * snd_pcm_hw_param_choose - choose a configuration defined by @params
1549 * @pcm: PCM instance
1550 * @params: the hw_params instance
1552 * Choose one configuration from configuration space defined by @params.
1553 * The configuration chosen is that obtained fixing in this order:
1554 * first access, first format, first subformat, min channels,
1555 * min rate, min period time, max buffer size, min tick time
1557 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1558 struct snd_pcm_hw_params *params)
1560 static int vars[] = {
1561 SNDRV_PCM_HW_PARAM_ACCESS,
1562 SNDRV_PCM_HW_PARAM_FORMAT,
1563 SNDRV_PCM_HW_PARAM_SUBFORMAT,
1564 SNDRV_PCM_HW_PARAM_CHANNELS,
1565 SNDRV_PCM_HW_PARAM_RATE,
1566 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1567 SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1568 SNDRV_PCM_HW_PARAM_TICK_TIME,
1573 for (v = vars; *v != -1; v++) {
1574 if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1575 err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1577 err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1578 if (snd_BUG_ON(err < 0))
1584 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1587 struct snd_pcm_runtime *runtime = substream->runtime;
1588 unsigned long flags;
1589 snd_pcm_stream_lock_irqsave(substream, flags);
1590 if (snd_pcm_running(substream) &&
1591 snd_pcm_update_hw_ptr(substream) >= 0)
1592 runtime->status->hw_ptr %= runtime->buffer_size;
1594 runtime->status->hw_ptr = 0;
1595 snd_pcm_stream_unlock_irqrestore(substream, flags);
1599 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1602 struct snd_pcm_channel_info *info = arg;
1603 struct snd_pcm_runtime *runtime = substream->runtime;
1605 if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1609 width = snd_pcm_format_physical_width(runtime->format);
1613 switch (runtime->access) {
1614 case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1615 case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1616 info->first = info->channel * width;
1617 info->step = runtime->channels * width;
1619 case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1620 case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1622 size_t size = runtime->dma_bytes / runtime->channels;
1623 info->first = info->channel * size * 8;
1634 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1637 struct snd_pcm_hw_params *params = arg;
1638 snd_pcm_format_t format;
1639 int channels, width;
1641 params->fifo_size = substream->runtime->hw.fifo_size;
1642 if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1643 format = params_format(params);
1644 channels = params_channels(params);
1645 width = snd_pcm_format_physical_width(format);
1646 params->fifo_size /= width * channels;
1652 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1653 * @substream: the pcm substream instance
1654 * @cmd: ioctl command
1655 * @arg: ioctl argument
1657 * Processes the generic ioctl commands for PCM.
1658 * Can be passed as the ioctl callback for PCM ops.
1660 * Returns zero if successful, or a negative error code on failure.
1662 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1663 unsigned int cmd, void *arg)
1666 case SNDRV_PCM_IOCTL1_INFO:
1668 case SNDRV_PCM_IOCTL1_RESET:
1669 return snd_pcm_lib_ioctl_reset(substream, arg);
1670 case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1671 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1672 case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1673 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1678 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1681 * snd_pcm_period_elapsed - update the pcm status for the next period
1682 * @substream: the pcm substream instance
1684 * This function is called from the interrupt handler when the
1685 * PCM has processed the period size. It will update the current
1686 * pointer, wake up sleepers, etc.
1688 * Even if more than one periods have elapsed since the last call, you
1689 * have to call this only once.
1691 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1693 struct snd_pcm_runtime *runtime;
1694 unsigned long flags;
1696 if (PCM_RUNTIME_CHECK(substream))
1698 runtime = substream->runtime;
1700 if (runtime->transfer_ack_begin)
1701 runtime->transfer_ack_begin(substream);
1703 snd_pcm_stream_lock_irqsave(substream, flags);
1704 if (!snd_pcm_running(substream) ||
1705 snd_pcm_update_hw_ptr0(substream, 1) < 0)
1708 if (substream->timer_running)
1709 snd_timer_interrupt(substream->timer, 1);
1711 snd_pcm_stream_unlock_irqrestore(substream, flags);
1712 if (runtime->transfer_ack_end)
1713 runtime->transfer_ack_end(substream);
1714 kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1717 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1720 * Wait until avail_min data becomes available
1721 * Returns a negative error code if any error occurs during operation.
1722 * The available space is stored on availp. When err = 0 and avail = 0
1723 * on the capture stream, it indicates the stream is in DRAINING state.
1725 static int wait_for_avail(struct snd_pcm_substream *substream,
1726 snd_pcm_uframes_t *availp)
1728 struct snd_pcm_runtime *runtime = substream->runtime;
1729 int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1732 snd_pcm_uframes_t avail = 0;
1735 init_waitqueue_entry(&wait, current);
1736 add_wait_queue(&runtime->tsleep, &wait);
1738 if (signal_pending(current)) {
1742 set_current_state(TASK_INTERRUPTIBLE);
1743 snd_pcm_stream_unlock_irq(substream);
1744 tout = schedule_timeout(msecs_to_jiffies(10000));
1745 snd_pcm_stream_lock_irq(substream);
1746 switch (runtime->status->state) {
1747 case SNDRV_PCM_STATE_SUSPENDED:
1750 case SNDRV_PCM_STATE_XRUN:
1753 case SNDRV_PCM_STATE_DRAINING:
1757 avail = 0; /* indicate draining */
1759 case SNDRV_PCM_STATE_OPEN:
1760 case SNDRV_PCM_STATE_SETUP:
1761 case SNDRV_PCM_STATE_DISCONNECTED:
1766 snd_printd("%s write error (DMA or IRQ trouble?)\n",
1767 is_playback ? "playback" : "capture");
1772 avail = snd_pcm_playback_avail(runtime);
1774 avail = snd_pcm_capture_avail(runtime);
1775 if (avail >= runtime->twake)
1779 remove_wait_queue(&runtime->tsleep, &wait);
1784 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1786 unsigned long data, unsigned int off,
1787 snd_pcm_uframes_t frames)
1789 struct snd_pcm_runtime *runtime = substream->runtime;
1791 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1792 if (substream->ops->copy) {
1793 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1796 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1797 if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1803 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1804 unsigned long data, unsigned int off,
1805 snd_pcm_uframes_t size);
1807 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1809 snd_pcm_uframes_t size,
1811 transfer_f transfer)
1813 struct snd_pcm_runtime *runtime = substream->runtime;
1814 snd_pcm_uframes_t xfer = 0;
1815 snd_pcm_uframes_t offset = 0;
1821 snd_pcm_stream_lock_irq(substream);
1822 switch (runtime->status->state) {
1823 case SNDRV_PCM_STATE_PREPARED:
1824 case SNDRV_PCM_STATE_RUNNING:
1825 case SNDRV_PCM_STATE_PAUSED:
1827 case SNDRV_PCM_STATE_XRUN:
1830 case SNDRV_PCM_STATE_SUSPENDED:
1838 runtime->twake = runtime->control->avail_min ? : 1;
1840 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1841 snd_pcm_uframes_t avail;
1842 snd_pcm_uframes_t cont;
1843 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1844 snd_pcm_update_hw_ptr(substream);
1845 avail = snd_pcm_playback_avail(runtime);
1851 runtime->twake = min_t(snd_pcm_uframes_t, size,
1852 runtime->control->avail_min ? : 1);
1853 err = wait_for_avail(substream, &avail);
1857 frames = size > avail ? avail : size;
1858 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1861 if (snd_BUG_ON(!frames)) {
1863 snd_pcm_stream_unlock_irq(substream);
1866 appl_ptr = runtime->control->appl_ptr;
1867 appl_ofs = appl_ptr % runtime->buffer_size;
1868 snd_pcm_stream_unlock_irq(substream);
1869 err = transfer(substream, appl_ofs, data, offset, frames);
1870 snd_pcm_stream_lock_irq(substream);
1873 switch (runtime->status->state) {
1874 case SNDRV_PCM_STATE_XRUN:
1877 case SNDRV_PCM_STATE_SUSPENDED:
1884 if (appl_ptr >= runtime->boundary)
1885 appl_ptr -= runtime->boundary;
1886 runtime->control->appl_ptr = appl_ptr;
1887 if (substream->ops->ack)
1888 substream->ops->ack(substream);
1893 if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1894 snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1895 err = snd_pcm_start(substream);
1902 if (xfer > 0 && err >= 0)
1903 snd_pcm_update_state(substream, runtime);
1904 snd_pcm_stream_unlock_irq(substream);
1905 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
1908 /* sanity-check for read/write methods */
1909 static int pcm_sanity_check(struct snd_pcm_substream *substream)
1911 struct snd_pcm_runtime *runtime;
1912 if (PCM_RUNTIME_CHECK(substream))
1914 runtime = substream->runtime;
1915 if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
1917 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1922 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
1924 struct snd_pcm_runtime *runtime;
1928 err = pcm_sanity_check(substream);
1931 runtime = substream->runtime;
1932 nonblock = !!(substream->f_flags & O_NONBLOCK);
1934 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
1935 runtime->channels > 1)
1937 return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
1938 snd_pcm_lib_write_transfer);
1941 EXPORT_SYMBOL(snd_pcm_lib_write);
1943 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
1945 unsigned long data, unsigned int off,
1946 snd_pcm_uframes_t frames)
1948 struct snd_pcm_runtime *runtime = substream->runtime;
1950 void __user **bufs = (void __user **)data;
1951 int channels = runtime->channels;
1953 if (substream->ops->copy) {
1954 if (snd_BUG_ON(!substream->ops->silence))
1956 for (c = 0; c < channels; ++c, ++bufs) {
1957 if (*bufs == NULL) {
1958 if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
1961 char __user *buf = *bufs + samples_to_bytes(runtime, off);
1962 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
1967 /* default transfer behaviour */
1968 size_t dma_csize = runtime->dma_bytes / channels;
1969 for (c = 0; c < channels; ++c, ++bufs) {
1970 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
1971 if (*bufs == NULL) {
1972 snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
1974 char __user *buf = *bufs + samples_to_bytes(runtime, off);
1975 if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
1983 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
1985 snd_pcm_uframes_t frames)
1987 struct snd_pcm_runtime *runtime;
1991 err = pcm_sanity_check(substream);
1994 runtime = substream->runtime;
1995 nonblock = !!(substream->f_flags & O_NONBLOCK);
1997 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
1999 return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2000 nonblock, snd_pcm_lib_writev_transfer);
2003 EXPORT_SYMBOL(snd_pcm_lib_writev);
2005 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
2007 unsigned long data, unsigned int off,
2008 snd_pcm_uframes_t frames)
2010 struct snd_pcm_runtime *runtime = substream->runtime;
2012 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2013 if (substream->ops->copy) {
2014 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2017 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2018 if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2024 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2026 snd_pcm_uframes_t size,
2028 transfer_f transfer)
2030 struct snd_pcm_runtime *runtime = substream->runtime;
2031 snd_pcm_uframes_t xfer = 0;
2032 snd_pcm_uframes_t offset = 0;
2038 snd_pcm_stream_lock_irq(substream);
2039 switch (runtime->status->state) {
2040 case SNDRV_PCM_STATE_PREPARED:
2041 if (size >= runtime->start_threshold) {
2042 err = snd_pcm_start(substream);
2047 case SNDRV_PCM_STATE_DRAINING:
2048 case SNDRV_PCM_STATE_RUNNING:
2049 case SNDRV_PCM_STATE_PAUSED:
2051 case SNDRV_PCM_STATE_XRUN:
2054 case SNDRV_PCM_STATE_SUSPENDED:
2062 runtime->twake = runtime->control->avail_min ? : 1;
2064 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2065 snd_pcm_uframes_t avail;
2066 snd_pcm_uframes_t cont;
2067 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2068 snd_pcm_update_hw_ptr(substream);
2069 avail = snd_pcm_capture_avail(runtime);
2071 if (runtime->status->state ==
2072 SNDRV_PCM_STATE_DRAINING) {
2073 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2080 runtime->twake = min_t(snd_pcm_uframes_t, size,
2081 runtime->control->avail_min ? : 1);
2082 err = wait_for_avail(substream, &avail);
2086 continue; /* draining */
2088 frames = size > avail ? avail : size;
2089 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2092 if (snd_BUG_ON(!frames)) {
2094 snd_pcm_stream_unlock_irq(substream);
2097 appl_ptr = runtime->control->appl_ptr;
2098 appl_ofs = appl_ptr % runtime->buffer_size;
2099 snd_pcm_stream_unlock_irq(substream);
2100 err = transfer(substream, appl_ofs, data, offset, frames);
2101 snd_pcm_stream_lock_irq(substream);
2104 switch (runtime->status->state) {
2105 case SNDRV_PCM_STATE_XRUN:
2108 case SNDRV_PCM_STATE_SUSPENDED:
2115 if (appl_ptr >= runtime->boundary)
2116 appl_ptr -= runtime->boundary;
2117 runtime->control->appl_ptr = appl_ptr;
2118 if (substream->ops->ack)
2119 substream->ops->ack(substream);
2127 if (xfer > 0 && err >= 0)
2128 snd_pcm_update_state(substream, runtime);
2129 snd_pcm_stream_unlock_irq(substream);
2130 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2133 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2135 struct snd_pcm_runtime *runtime;
2139 err = pcm_sanity_check(substream);
2142 runtime = substream->runtime;
2143 nonblock = !!(substream->f_flags & O_NONBLOCK);
2144 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2146 return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2149 EXPORT_SYMBOL(snd_pcm_lib_read);
2151 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2153 unsigned long data, unsigned int off,
2154 snd_pcm_uframes_t frames)
2156 struct snd_pcm_runtime *runtime = substream->runtime;
2158 void __user **bufs = (void __user **)data;
2159 int channels = runtime->channels;
2161 if (substream->ops->copy) {
2162 for (c = 0; c < channels; ++c, ++bufs) {
2166 buf = *bufs + samples_to_bytes(runtime, off);
2167 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2171 snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2172 for (c = 0; c < channels; ++c, ++bufs) {
2178 hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2179 buf = *bufs + samples_to_bytes(runtime, off);
2180 if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2187 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2189 snd_pcm_uframes_t frames)
2191 struct snd_pcm_runtime *runtime;
2195 err = pcm_sanity_check(substream);
2198 runtime = substream->runtime;
2199 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2202 nonblock = !!(substream->f_flags & O_NONBLOCK);
2203 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2205 return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2208 EXPORT_SYMBOL(snd_pcm_lib_readv);