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 runtime->silence_filled = avail > 0 ? avail : 0;
71 runtime->silence_start = (runtime->status->hw_ptr +
72 runtime->silence_filled) %
75 ofs = runtime->status->hw_ptr;
76 frames = new_hw_ptr - ofs;
77 if ((snd_pcm_sframes_t)frames < 0)
78 frames += runtime->boundary;
79 runtime->silence_filled -= frames;
80 if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
81 runtime->silence_filled = 0;
82 runtime->silence_start = new_hw_ptr;
84 runtime->silence_start = ofs;
87 frames = runtime->buffer_size - runtime->silence_filled;
89 if (snd_BUG_ON(frames > runtime->buffer_size))
93 ofs = runtime->silence_start % runtime->buffer_size;
95 transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
96 if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
97 runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
98 if (substream->ops->silence) {
100 err = substream->ops->silence(substream, -1, ofs, transfer);
103 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
104 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
108 unsigned int channels = runtime->channels;
109 if (substream->ops->silence) {
110 for (c = 0; c < channels; ++c) {
112 err = substream->ops->silence(substream, c, ofs, transfer);
116 size_t dma_csize = runtime->dma_bytes / channels;
117 for (c = 0; c < channels; ++c) {
118 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
119 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
123 runtime->silence_filled += transfer;
129 static void pcm_debug_name(struct snd_pcm_substream *substream,
130 char *name, size_t len)
132 snprintf(name, len, "pcmC%dD%d%c:%d",
133 substream->pcm->card->number,
134 substream->pcm->device,
135 substream->stream ? 'c' : 'p',
139 #define XRUN_DEBUG_BASIC (1<<0)
140 #define XRUN_DEBUG_STACK (1<<1) /* dump also stack */
141 #define XRUN_DEBUG_JIFFIESCHECK (1<<2) /* do jiffies check */
142 #define XRUN_DEBUG_PERIODUPDATE (1<<3) /* full period update info */
143 #define XRUN_DEBUG_HWPTRUPDATE (1<<4) /* full hwptr update info */
144 #define XRUN_DEBUG_LOG (1<<5) /* show last 10 positions on err */
145 #define XRUN_DEBUG_LOGONCE (1<<6) /* do above only once */
147 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
149 #define xrun_debug(substream, mask) \
150 ((substream)->pstr->xrun_debug & (mask))
152 #define dump_stack_on_xrun(substream) do { \
153 if (xrun_debug(substream, XRUN_DEBUG_STACK)) \
157 static void xrun(struct snd_pcm_substream *substream)
159 struct snd_pcm_runtime *runtime = substream->runtime;
161 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
162 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
163 snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
164 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
166 pcm_debug_name(substream, name, sizeof(name));
167 snd_printd(KERN_DEBUG "XRUN: %s\n", name);
168 dump_stack_on_xrun(substream);
172 #define hw_ptr_error(substream, fmt, args...) \
174 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) { \
175 xrun_log_show(substream); \
176 if (printk_ratelimit()) { \
177 snd_printd("PCM: " fmt, ##args); \
179 dump_stack_on_xrun(substream); \
183 #define XRUN_LOG_CNT 10
185 struct hwptr_log_entry {
186 unsigned long jiffies;
187 snd_pcm_uframes_t pos;
188 snd_pcm_uframes_t period_size;
189 snd_pcm_uframes_t buffer_size;
190 snd_pcm_uframes_t old_hw_ptr;
191 snd_pcm_uframes_t hw_ptr_base;
194 struct snd_pcm_hwptr_log {
197 struct hwptr_log_entry entries[XRUN_LOG_CNT];
200 static void xrun_log(struct snd_pcm_substream *substream,
201 snd_pcm_uframes_t pos)
203 struct snd_pcm_runtime *runtime = substream->runtime;
204 struct snd_pcm_hwptr_log *log = runtime->hwptr_log;
205 struct hwptr_log_entry *entry;
208 log = kzalloc(sizeof(*log), GFP_ATOMIC);
211 runtime->hwptr_log = log;
213 if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
216 entry = &log->entries[log->idx];
217 entry->jiffies = jiffies;
219 entry->period_size = runtime->period_size;
220 entry->buffer_size = runtime->buffer_size;;
221 entry->old_hw_ptr = runtime->status->hw_ptr;
222 entry->hw_ptr_base = runtime->hw_ptr_base;
223 log->idx = (log->idx + 1) % XRUN_LOG_CNT;
226 static void xrun_log_show(struct snd_pcm_substream *substream)
228 struct snd_pcm_hwptr_log *log = substream->runtime->hwptr_log;
229 struct hwptr_log_entry *entry;
236 if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
238 pcm_debug_name(substream, name, sizeof(name));
239 for (cnt = 0, idx = log->idx; cnt < XRUN_LOG_CNT; cnt++) {
240 entry = &log->entries[idx];
241 if (entry->period_size == 0)
243 snd_printd("hwptr log: %s: j=%lu, pos=%ld/%ld/%ld, "
245 name, entry->jiffies, (unsigned long)entry->pos,
246 (unsigned long)entry->period_size,
247 (unsigned long)entry->buffer_size,
248 (unsigned long)entry->old_hw_ptr,
249 (unsigned long)entry->hw_ptr_base);
256 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
258 #define xrun_debug(substream, mask) 0
259 #define xrun(substream) do { } while (0)
260 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
261 #define xrun_log(substream, pos) do { } while (0)
262 #define xrun_log_show(substream) do { } while (0)
266 int snd_pcm_update_state(struct snd_pcm_substream *substream,
267 struct snd_pcm_runtime *runtime)
269 snd_pcm_uframes_t avail;
271 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
272 avail = snd_pcm_playback_avail(runtime);
274 avail = snd_pcm_capture_avail(runtime);
275 if (avail > runtime->avail_max)
276 runtime->avail_max = avail;
277 if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
278 if (avail >= runtime->buffer_size) {
279 snd_pcm_drain_done(substream);
283 if (avail >= runtime->stop_threshold) {
288 if (!runtime->nowake && avail >= runtime->control->avail_min)
289 wake_up(&runtime->sleep);
293 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
294 unsigned int in_interrupt)
296 struct snd_pcm_runtime *runtime = substream->runtime;
297 snd_pcm_uframes_t pos;
298 snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
299 snd_pcm_sframes_t hdelta, delta;
300 unsigned long jdelta;
302 old_hw_ptr = runtime->status->hw_ptr;
303 pos = substream->ops->pointer(substream);
304 if (pos == SNDRV_PCM_POS_XRUN) {
308 if (pos >= runtime->buffer_size) {
309 if (printk_ratelimit()) {
311 pcm_debug_name(substream, name, sizeof(name));
312 xrun_log_show(substream);
313 snd_printd(KERN_ERR "BUG: %s, pos = %ld, "
314 "buffer size = %ld, period size = %ld\n",
315 name, pos, runtime->buffer_size,
316 runtime->period_size);
320 pos -= pos % runtime->min_align;
321 if (xrun_debug(substream, XRUN_DEBUG_LOG))
322 xrun_log(substream, pos);
323 hw_base = runtime->hw_ptr_base;
324 new_hw_ptr = hw_base + pos;
326 /* we know that one period was processed */
327 /* delta = "expected next hw_ptr" for in_interrupt != 0 */
328 delta = old_hw_ptr - (old_hw_ptr % runtime->period_size)
329 + runtime->period_size;
330 if (delta > new_hw_ptr) {
331 hw_base += runtime->buffer_size;
332 if (hw_base >= runtime->boundary)
334 new_hw_ptr = hw_base + pos;
338 /* new_hw_ptr might be lower than old_hw_ptr in case when */
339 /* pointer crosses the end of the ring buffer */
340 if (new_hw_ptr < old_hw_ptr) {
341 hw_base += runtime->buffer_size;
342 if (hw_base >= runtime->boundary)
344 new_hw_ptr = hw_base + pos;
347 delta = (new_hw_ptr - old_hw_ptr) % runtime->boundary;
348 if (xrun_debug(substream, in_interrupt ?
349 XRUN_DEBUG_PERIODUPDATE : XRUN_DEBUG_HWPTRUPDATE)) {
351 pcm_debug_name(substream, name, sizeof(name));
352 snd_printd("%s_update: %s: pos=%u/%u/%u, "
353 "hwptr=%ld/%ld/%ld/%ld\n",
354 in_interrupt ? "period" : "hwptr",
357 (unsigned int)runtime->period_size,
358 (unsigned int)runtime->buffer_size,
359 (unsigned long)delta,
360 (unsigned long)old_hw_ptr,
361 (unsigned long)new_hw_ptr,
362 (unsigned long)runtime->hw_ptr_base);
364 /* something must be really wrong */
365 if (delta >= runtime->buffer_size + runtime->period_size) {
366 hw_ptr_error(substream,
367 "Unexpected hw_pointer value %s"
368 "(stream=%i, pos=%ld, new_hw_ptr=%ld, "
370 in_interrupt ? "[Q] " : "[P]",
371 substream->stream, (long)pos,
372 (long)new_hw_ptr, (long)old_hw_ptr);
376 /* Do jiffies check only in xrun_debug mode */
377 if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
378 goto no_jiffies_check;
380 /* Skip the jiffies check for hardwares with BATCH flag.
381 * Such hardware usually just increases the position at each IRQ,
382 * thus it can't give any strange position.
384 if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
385 goto no_jiffies_check;
387 if (hdelta < runtime->delay)
388 goto no_jiffies_check;
389 hdelta -= runtime->delay;
390 jdelta = jiffies - runtime->hw_ptr_jiffies;
391 if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
393 (((runtime->period_size * HZ) / runtime->rate)
395 /* move new_hw_ptr according jiffies not pos variable */
396 new_hw_ptr = old_hw_ptr;
398 /* use loop to avoid checks for delta overflows */
399 /* the delta value is small or zero in most cases */
401 new_hw_ptr += runtime->period_size;
402 if (new_hw_ptr >= runtime->boundary)
403 new_hw_ptr -= runtime->boundary;
406 /* align hw_base to buffer_size */
407 hw_ptr_error(substream,
408 "hw_ptr skipping! %s"
409 "(pos=%ld, delta=%ld, period=%ld, "
410 "jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
411 in_interrupt ? "[Q] " : "",
412 (long)pos, (long)hdelta,
413 (long)runtime->period_size, jdelta,
414 ((hdelta * HZ) / runtime->rate), hw_base,
415 (unsigned long)old_hw_ptr,
416 (unsigned long)new_hw_ptr);
417 /* reset values to proper state */
419 hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
422 if (delta > runtime->period_size + runtime->period_size / 2) {
423 hw_ptr_error(substream,
424 "Lost interrupts? %s"
425 "(stream=%i, delta=%ld, new_hw_ptr=%ld, "
427 in_interrupt ? "[Q] " : "",
428 substream->stream, (long)delta,
433 if (runtime->status->hw_ptr == new_hw_ptr)
436 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
437 runtime->silence_size > 0)
438 snd_pcm_playback_silence(substream, new_hw_ptr);
440 runtime->hw_ptr_base = hw_base;
441 runtime->status->hw_ptr = new_hw_ptr;
442 runtime->hw_ptr_jiffies = jiffies;
443 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
444 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
446 return snd_pcm_update_state(substream, runtime);
449 /* CAUTION: call it with irq disabled */
450 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
452 return snd_pcm_update_hw_ptr0(substream, 0);
456 * snd_pcm_set_ops - set the PCM operators
457 * @pcm: the pcm instance
458 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
459 * @ops: the operator table
461 * Sets the given PCM operators to the pcm instance.
463 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction, struct snd_pcm_ops *ops)
465 struct snd_pcm_str *stream = &pcm->streams[direction];
466 struct snd_pcm_substream *substream;
468 for (substream = stream->substream; substream != NULL; substream = substream->next)
469 substream->ops = ops;
472 EXPORT_SYMBOL(snd_pcm_set_ops);
475 * snd_pcm_sync - set the PCM sync id
476 * @substream: the pcm substream
478 * Sets the PCM sync identifier for the card.
480 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
482 struct snd_pcm_runtime *runtime = substream->runtime;
484 runtime->sync.id32[0] = substream->pcm->card->number;
485 runtime->sync.id32[1] = -1;
486 runtime->sync.id32[2] = -1;
487 runtime->sync.id32[3] = -1;
490 EXPORT_SYMBOL(snd_pcm_set_sync);
493 * Standard ioctl routine
496 static inline unsigned int div32(unsigned int a, unsigned int b,
507 static inline unsigned int div_down(unsigned int a, unsigned int b)
514 static inline unsigned int div_up(unsigned int a, unsigned int b)
526 static inline unsigned int mul(unsigned int a, unsigned int b)
530 if (div_down(UINT_MAX, a) < b)
535 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
536 unsigned int c, unsigned int *r)
538 u_int64_t n = (u_int64_t) a * b;
544 n = div_u64_rem(n, c, r);
553 * snd_interval_refine - refine the interval value of configurator
554 * @i: the interval value to refine
555 * @v: the interval value to refer to
557 * Refines the interval value with the reference value.
558 * The interval is changed to the range satisfying both intervals.
559 * The interval status (min, max, integer, etc.) are evaluated.
561 * Returns non-zero if the value is changed, zero if not changed.
563 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
566 if (snd_BUG_ON(snd_interval_empty(i)))
568 if (i->min < v->min) {
570 i->openmin = v->openmin;
572 } else if (i->min == v->min && !i->openmin && v->openmin) {
576 if (i->max > v->max) {
578 i->openmax = v->openmax;
580 } else if (i->max == v->max && !i->openmax && v->openmax) {
584 if (!i->integer && v->integer) {
597 } else if (!i->openmin && !i->openmax && i->min == i->max)
599 if (snd_interval_checkempty(i)) {
600 snd_interval_none(i);
606 EXPORT_SYMBOL(snd_interval_refine);
608 static int snd_interval_refine_first(struct snd_interval *i)
610 if (snd_BUG_ON(snd_interval_empty(i)))
612 if (snd_interval_single(i))
615 i->openmax = i->openmin;
621 static int snd_interval_refine_last(struct snd_interval *i)
623 if (snd_BUG_ON(snd_interval_empty(i)))
625 if (snd_interval_single(i))
628 i->openmin = i->openmax;
634 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
636 if (a->empty || b->empty) {
637 snd_interval_none(c);
641 c->min = mul(a->min, b->min);
642 c->openmin = (a->openmin || b->openmin);
643 c->max = mul(a->max, b->max);
644 c->openmax = (a->openmax || b->openmax);
645 c->integer = (a->integer && b->integer);
649 * snd_interval_div - refine the interval value with division
656 * Returns non-zero if the value is changed, zero if not changed.
658 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
661 if (a->empty || b->empty) {
662 snd_interval_none(c);
666 c->min = div32(a->min, b->max, &r);
667 c->openmin = (r || a->openmin || b->openmax);
669 c->max = div32(a->max, b->min, &r);
674 c->openmax = (a->openmax || b->openmin);
683 * snd_interval_muldivk - refine the interval value
686 * @k: divisor (as integer)
691 * Returns non-zero if the value is changed, zero if not changed.
693 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
694 unsigned int k, struct snd_interval *c)
697 if (a->empty || b->empty) {
698 snd_interval_none(c);
702 c->min = muldiv32(a->min, b->min, k, &r);
703 c->openmin = (r || a->openmin || b->openmin);
704 c->max = muldiv32(a->max, b->max, k, &r);
709 c->openmax = (a->openmax || b->openmax);
714 * snd_interval_mulkdiv - refine the interval value
716 * @k: dividend 2 (as integer)
722 * Returns non-zero if the value is changed, zero if not changed.
724 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
725 const struct snd_interval *b, struct snd_interval *c)
728 if (a->empty || b->empty) {
729 snd_interval_none(c);
733 c->min = muldiv32(a->min, k, b->max, &r);
734 c->openmin = (r || a->openmin || b->openmax);
736 c->max = muldiv32(a->max, k, b->min, &r);
741 c->openmax = (a->openmax || b->openmin);
753 * snd_interval_ratnum - refine the interval value
754 * @i: interval to refine
755 * @rats_count: number of ratnum_t
756 * @rats: ratnum_t array
757 * @nump: pointer to store the resultant numerator
758 * @denp: pointer to store the resultant denominator
760 * Returns non-zero if the value is changed, zero if not changed.
762 int snd_interval_ratnum(struct snd_interval *i,
763 unsigned int rats_count, struct snd_ratnum *rats,
764 unsigned int *nump, unsigned int *denp)
766 unsigned int best_num, best_diff, best_den;
768 struct snd_interval t;
771 best_num = best_den = best_diff = 0;
772 for (k = 0; k < rats_count; ++k) {
773 unsigned int num = rats[k].num;
775 unsigned int q = i->min;
779 den = div_up(num, q);
780 if (den < rats[k].den_min)
782 if (den > rats[k].den_max)
783 den = rats[k].den_max;
786 r = (den - rats[k].den_min) % rats[k].den_step;
790 diff = num - q * den;
792 diff * best_den < best_diff * den) {
802 t.min = div_down(best_num, best_den);
803 t.openmin = !!(best_num % best_den);
805 best_num = best_den = best_diff = 0;
806 for (k = 0; k < rats_count; ++k) {
807 unsigned int num = rats[k].num;
809 unsigned int q = i->max;
815 den = div_down(num, q);
816 if (den > rats[k].den_max)
818 if (den < rats[k].den_min)
819 den = rats[k].den_min;
822 r = (den - rats[k].den_min) % rats[k].den_step;
824 den += rats[k].den_step - r;
826 diff = q * den - num;
828 diff * best_den < best_diff * den) {
838 t.max = div_up(best_num, best_den);
839 t.openmax = !!(best_num % best_den);
841 err = snd_interval_refine(i, &t);
845 if (snd_interval_single(i)) {
854 EXPORT_SYMBOL(snd_interval_ratnum);
857 * snd_interval_ratden - refine the interval value
858 * @i: interval to refine
859 * @rats_count: number of struct ratden
860 * @rats: struct ratden array
861 * @nump: pointer to store the resultant numerator
862 * @denp: pointer to store the resultant denominator
864 * Returns non-zero if the value is changed, zero if not changed.
866 static int snd_interval_ratden(struct snd_interval *i,
867 unsigned int rats_count, struct snd_ratden *rats,
868 unsigned int *nump, unsigned int *denp)
870 unsigned int best_num, best_diff, best_den;
872 struct snd_interval t;
875 best_num = best_den = best_diff = 0;
876 for (k = 0; k < rats_count; ++k) {
878 unsigned int den = rats[k].den;
879 unsigned int q = i->min;
882 if (num > rats[k].num_max)
884 if (num < rats[k].num_min)
885 num = rats[k].num_max;
888 r = (num - rats[k].num_min) % rats[k].num_step;
890 num += rats[k].num_step - r;
892 diff = num - q * den;
894 diff * best_den < best_diff * den) {
904 t.min = div_down(best_num, best_den);
905 t.openmin = !!(best_num % best_den);
907 best_num = best_den = best_diff = 0;
908 for (k = 0; k < rats_count; ++k) {
910 unsigned int den = rats[k].den;
911 unsigned int q = i->max;
914 if (num < rats[k].num_min)
916 if (num > rats[k].num_max)
917 num = rats[k].num_max;
920 r = (num - rats[k].num_min) % rats[k].num_step;
924 diff = q * den - num;
926 diff * best_den < best_diff * den) {
936 t.max = div_up(best_num, best_den);
937 t.openmax = !!(best_num % best_den);
939 err = snd_interval_refine(i, &t);
943 if (snd_interval_single(i)) {
953 * snd_interval_list - refine the interval value from the list
954 * @i: the interval value to refine
955 * @count: the number of elements in the list
956 * @list: the value list
957 * @mask: the bit-mask to evaluate
959 * Refines the interval value from the list.
960 * When mask is non-zero, only the elements corresponding to bit 1 are
963 * Returns non-zero if the value is changed, zero if not changed.
965 int snd_interval_list(struct snd_interval *i, unsigned int count, unsigned int *list, unsigned int mask)
968 struct snd_interval list_range;
974 snd_interval_any(&list_range);
975 list_range.min = UINT_MAX;
977 for (k = 0; k < count; k++) {
978 if (mask && !(mask & (1 << k)))
980 if (!snd_interval_test(i, list[k]))
982 list_range.min = min(list_range.min, list[k]);
983 list_range.max = max(list_range.max, list[k]);
985 return snd_interval_refine(i, &list_range);
988 EXPORT_SYMBOL(snd_interval_list);
990 static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
994 n = (i->min - min) % step;
995 if (n != 0 || i->openmin) {
999 n = (i->max - min) % step;
1000 if (n != 0 || i->openmax) {
1004 if (snd_interval_checkempty(i)) {
1011 /* Info constraints helpers */
1014 * snd_pcm_hw_rule_add - add the hw-constraint rule
1015 * @runtime: the pcm runtime instance
1016 * @cond: condition bits
1017 * @var: the variable to evaluate
1018 * @func: the evaluation function
1019 * @private: the private data pointer passed to function
1020 * @dep: the dependent variables
1022 * Returns zero if successful, or a negative error code on failure.
1024 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1026 snd_pcm_hw_rule_func_t func, void *private,
1029 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1030 struct snd_pcm_hw_rule *c;
1033 va_start(args, dep);
1034 if (constrs->rules_num >= constrs->rules_all) {
1035 struct snd_pcm_hw_rule *new;
1036 unsigned int new_rules = constrs->rules_all + 16;
1037 new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1040 if (constrs->rules) {
1041 memcpy(new, constrs->rules,
1042 constrs->rules_num * sizeof(*c));
1043 kfree(constrs->rules);
1045 constrs->rules = new;
1046 constrs->rules_all = new_rules;
1048 c = &constrs->rules[constrs->rules_num];
1052 c->private = private;
1055 if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps)))
1060 dep = va_arg(args, int);
1062 constrs->rules_num++;
1067 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1070 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1071 * @runtime: PCM runtime instance
1072 * @var: hw_params variable to apply the mask
1073 * @mask: the bitmap mask
1075 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1077 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1080 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1081 struct snd_mask *maskp = constrs_mask(constrs, var);
1082 *maskp->bits &= mask;
1083 memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1084 if (*maskp->bits == 0)
1090 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1091 * @runtime: PCM runtime instance
1092 * @var: hw_params variable to apply the mask
1093 * @mask: the 64bit bitmap mask
1095 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1097 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1100 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1101 struct snd_mask *maskp = constrs_mask(constrs, var);
1102 maskp->bits[0] &= (u_int32_t)mask;
1103 maskp->bits[1] &= (u_int32_t)(mask >> 32);
1104 memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1105 if (! maskp->bits[0] && ! maskp->bits[1])
1111 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1112 * @runtime: PCM runtime instance
1113 * @var: hw_params variable to apply the integer constraint
1115 * Apply the constraint of integer to an interval parameter.
1117 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1119 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1120 return snd_interval_setinteger(constrs_interval(constrs, var));
1123 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1126 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1127 * @runtime: PCM runtime instance
1128 * @var: hw_params variable to apply the range
1129 * @min: the minimal value
1130 * @max: the maximal value
1132 * Apply the min/max range constraint to an interval parameter.
1134 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1135 unsigned int min, unsigned int max)
1137 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1138 struct snd_interval t;
1141 t.openmin = t.openmax = 0;
1143 return snd_interval_refine(constrs_interval(constrs, var), &t);
1146 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1148 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1149 struct snd_pcm_hw_rule *rule)
1151 struct snd_pcm_hw_constraint_list *list = rule->private;
1152 return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1157 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1158 * @runtime: PCM runtime instance
1159 * @cond: condition bits
1160 * @var: hw_params variable to apply the list constraint
1163 * Apply the list of constraints to an interval parameter.
1165 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1167 snd_pcm_hw_param_t var,
1168 struct snd_pcm_hw_constraint_list *l)
1170 return snd_pcm_hw_rule_add(runtime, cond, var,
1171 snd_pcm_hw_rule_list, l,
1175 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1177 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1178 struct snd_pcm_hw_rule *rule)
1180 struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1181 unsigned int num = 0, den = 0;
1183 err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1184 r->nrats, r->rats, &num, &den);
1185 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1186 params->rate_num = num;
1187 params->rate_den = den;
1193 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1194 * @runtime: PCM runtime instance
1195 * @cond: condition bits
1196 * @var: hw_params variable to apply the ratnums constraint
1197 * @r: struct snd_ratnums constriants
1199 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1201 snd_pcm_hw_param_t var,
1202 struct snd_pcm_hw_constraint_ratnums *r)
1204 return snd_pcm_hw_rule_add(runtime, cond, var,
1205 snd_pcm_hw_rule_ratnums, r,
1209 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1211 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1212 struct snd_pcm_hw_rule *rule)
1214 struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1215 unsigned int num = 0, den = 0;
1216 int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1217 r->nrats, r->rats, &num, &den);
1218 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1219 params->rate_num = num;
1220 params->rate_den = den;
1226 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1227 * @runtime: PCM runtime instance
1228 * @cond: condition bits
1229 * @var: hw_params variable to apply the ratdens constraint
1230 * @r: struct snd_ratdens constriants
1232 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1234 snd_pcm_hw_param_t var,
1235 struct snd_pcm_hw_constraint_ratdens *r)
1237 return snd_pcm_hw_rule_add(runtime, cond, var,
1238 snd_pcm_hw_rule_ratdens, r,
1242 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1244 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1245 struct snd_pcm_hw_rule *rule)
1247 unsigned int l = (unsigned long) rule->private;
1248 int width = l & 0xffff;
1249 unsigned int msbits = l >> 16;
1250 struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1251 if (snd_interval_single(i) && snd_interval_value(i) == width)
1252 params->msbits = msbits;
1257 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1258 * @runtime: PCM runtime instance
1259 * @cond: condition bits
1260 * @width: sample bits width
1261 * @msbits: msbits width
1263 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1266 unsigned int msbits)
1268 unsigned long l = (msbits << 16) | width;
1269 return snd_pcm_hw_rule_add(runtime, cond, -1,
1270 snd_pcm_hw_rule_msbits,
1272 SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1275 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1277 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1278 struct snd_pcm_hw_rule *rule)
1280 unsigned long step = (unsigned long) rule->private;
1281 return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1285 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1286 * @runtime: PCM runtime instance
1287 * @cond: condition bits
1288 * @var: hw_params variable to apply the step constraint
1291 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1293 snd_pcm_hw_param_t var,
1296 return snd_pcm_hw_rule_add(runtime, cond, var,
1297 snd_pcm_hw_rule_step, (void *) step,
1301 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1303 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1305 static unsigned int pow2_sizes[] = {
1306 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1307 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1308 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1309 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1311 return snd_interval_list(hw_param_interval(params, rule->var),
1312 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1316 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1317 * @runtime: PCM runtime instance
1318 * @cond: condition bits
1319 * @var: hw_params variable to apply the power-of-2 constraint
1321 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1323 snd_pcm_hw_param_t var)
1325 return snd_pcm_hw_rule_add(runtime, cond, var,
1326 snd_pcm_hw_rule_pow2, NULL,
1330 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1332 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1333 snd_pcm_hw_param_t var)
1335 if (hw_is_mask(var)) {
1336 snd_mask_any(hw_param_mask(params, var));
1337 params->cmask |= 1 << var;
1338 params->rmask |= 1 << var;
1341 if (hw_is_interval(var)) {
1342 snd_interval_any(hw_param_interval(params, var));
1343 params->cmask |= 1 << var;
1344 params->rmask |= 1 << var;
1350 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1353 memset(params, 0, sizeof(*params));
1354 for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1355 _snd_pcm_hw_param_any(params, k);
1356 for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1357 _snd_pcm_hw_param_any(params, k);
1361 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1364 * snd_pcm_hw_param_value - return @params field @var value
1365 * @params: the hw_params instance
1366 * @var: parameter to retrieve
1367 * @dir: pointer to the direction (-1,0,1) or %NULL
1369 * Return the value for field @var if it's fixed in configuration space
1370 * defined by @params. Return -%EINVAL otherwise.
1372 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1373 snd_pcm_hw_param_t var, int *dir)
1375 if (hw_is_mask(var)) {
1376 const struct snd_mask *mask = hw_param_mask_c(params, var);
1377 if (!snd_mask_single(mask))
1381 return snd_mask_value(mask);
1383 if (hw_is_interval(var)) {
1384 const struct snd_interval *i = hw_param_interval_c(params, var);
1385 if (!snd_interval_single(i))
1389 return snd_interval_value(i);
1394 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1396 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1397 snd_pcm_hw_param_t var)
1399 if (hw_is_mask(var)) {
1400 snd_mask_none(hw_param_mask(params, var));
1401 params->cmask |= 1 << var;
1402 params->rmask |= 1 << var;
1403 } else if (hw_is_interval(var)) {
1404 snd_interval_none(hw_param_interval(params, var));
1405 params->cmask |= 1 << var;
1406 params->rmask |= 1 << var;
1412 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1414 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1415 snd_pcm_hw_param_t var)
1418 if (hw_is_mask(var))
1419 changed = snd_mask_refine_first(hw_param_mask(params, var));
1420 else if (hw_is_interval(var))
1421 changed = snd_interval_refine_first(hw_param_interval(params, var));
1425 params->cmask |= 1 << var;
1426 params->rmask |= 1 << var;
1433 * snd_pcm_hw_param_first - refine config space and return minimum value
1434 * @pcm: PCM instance
1435 * @params: the hw_params instance
1436 * @var: parameter to retrieve
1437 * @dir: pointer to the direction (-1,0,1) or %NULL
1439 * Inside configuration space defined by @params remove from @var all
1440 * values > minimum. Reduce configuration space accordingly.
1441 * Return the minimum.
1443 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1444 struct snd_pcm_hw_params *params,
1445 snd_pcm_hw_param_t var, int *dir)
1447 int changed = _snd_pcm_hw_param_first(params, var);
1450 if (params->rmask) {
1451 int err = snd_pcm_hw_refine(pcm, params);
1452 if (snd_BUG_ON(err < 0))
1455 return snd_pcm_hw_param_value(params, var, dir);
1458 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1460 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1461 snd_pcm_hw_param_t var)
1464 if (hw_is_mask(var))
1465 changed = snd_mask_refine_last(hw_param_mask(params, var));
1466 else if (hw_is_interval(var))
1467 changed = snd_interval_refine_last(hw_param_interval(params, var));
1471 params->cmask |= 1 << var;
1472 params->rmask |= 1 << var;
1479 * snd_pcm_hw_param_last - refine config space and return maximum value
1480 * @pcm: PCM instance
1481 * @params: the hw_params instance
1482 * @var: parameter to retrieve
1483 * @dir: pointer to the direction (-1,0,1) or %NULL
1485 * Inside configuration space defined by @params remove from @var all
1486 * values < maximum. Reduce configuration space accordingly.
1487 * Return the maximum.
1489 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1490 struct snd_pcm_hw_params *params,
1491 snd_pcm_hw_param_t var, int *dir)
1493 int changed = _snd_pcm_hw_param_last(params, var);
1496 if (params->rmask) {
1497 int err = snd_pcm_hw_refine(pcm, params);
1498 if (snd_BUG_ON(err < 0))
1501 return snd_pcm_hw_param_value(params, var, dir);
1504 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1507 * snd_pcm_hw_param_choose - choose a configuration defined by @params
1508 * @pcm: PCM instance
1509 * @params: the hw_params instance
1511 * Choose one configuration from configuration space defined by @params.
1512 * The configuration chosen is that obtained fixing in this order:
1513 * first access, first format, first subformat, min channels,
1514 * min rate, min period time, max buffer size, min tick time
1516 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1517 struct snd_pcm_hw_params *params)
1519 static int vars[] = {
1520 SNDRV_PCM_HW_PARAM_ACCESS,
1521 SNDRV_PCM_HW_PARAM_FORMAT,
1522 SNDRV_PCM_HW_PARAM_SUBFORMAT,
1523 SNDRV_PCM_HW_PARAM_CHANNELS,
1524 SNDRV_PCM_HW_PARAM_RATE,
1525 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1526 SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1527 SNDRV_PCM_HW_PARAM_TICK_TIME,
1532 for (v = vars; *v != -1; v++) {
1533 if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1534 err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1536 err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1537 if (snd_BUG_ON(err < 0))
1543 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1546 struct snd_pcm_runtime *runtime = substream->runtime;
1547 unsigned long flags;
1548 snd_pcm_stream_lock_irqsave(substream, flags);
1549 if (snd_pcm_running(substream) &&
1550 snd_pcm_update_hw_ptr(substream) >= 0)
1551 runtime->status->hw_ptr %= runtime->buffer_size;
1553 runtime->status->hw_ptr = 0;
1554 snd_pcm_stream_unlock_irqrestore(substream, flags);
1558 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1561 struct snd_pcm_channel_info *info = arg;
1562 struct snd_pcm_runtime *runtime = substream->runtime;
1564 if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1568 width = snd_pcm_format_physical_width(runtime->format);
1572 switch (runtime->access) {
1573 case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1574 case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1575 info->first = info->channel * width;
1576 info->step = runtime->channels * width;
1578 case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1579 case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1581 size_t size = runtime->dma_bytes / runtime->channels;
1582 info->first = info->channel * size * 8;
1593 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1596 struct snd_pcm_hw_params *params = arg;
1597 snd_pcm_format_t format;
1598 int channels, width;
1600 params->fifo_size = substream->runtime->hw.fifo_size;
1601 if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1602 format = params_format(params);
1603 channels = params_channels(params);
1604 width = snd_pcm_format_physical_width(format);
1605 params->fifo_size /= width * channels;
1611 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1612 * @substream: the pcm substream instance
1613 * @cmd: ioctl command
1614 * @arg: ioctl argument
1616 * Processes the generic ioctl commands for PCM.
1617 * Can be passed as the ioctl callback for PCM ops.
1619 * Returns zero if successful, or a negative error code on failure.
1621 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1622 unsigned int cmd, void *arg)
1625 case SNDRV_PCM_IOCTL1_INFO:
1627 case SNDRV_PCM_IOCTL1_RESET:
1628 return snd_pcm_lib_ioctl_reset(substream, arg);
1629 case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1630 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1631 case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1632 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1637 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1640 * snd_pcm_period_elapsed - update the pcm status for the next period
1641 * @substream: the pcm substream instance
1643 * This function is called from the interrupt handler when the
1644 * PCM has processed the period size. It will update the current
1645 * pointer, wake up sleepers, etc.
1647 * Even if more than one periods have elapsed since the last call, you
1648 * have to call this only once.
1650 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1652 struct snd_pcm_runtime *runtime;
1653 unsigned long flags;
1655 if (PCM_RUNTIME_CHECK(substream))
1657 runtime = substream->runtime;
1659 if (runtime->transfer_ack_begin)
1660 runtime->transfer_ack_begin(substream);
1662 snd_pcm_stream_lock_irqsave(substream, flags);
1663 if (!snd_pcm_running(substream) ||
1664 snd_pcm_update_hw_ptr0(substream, 1) < 0)
1667 if (substream->timer_running)
1668 snd_timer_interrupt(substream->timer, 1);
1670 snd_pcm_stream_unlock_irqrestore(substream, flags);
1671 if (runtime->transfer_ack_end)
1672 runtime->transfer_ack_end(substream);
1673 kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1676 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1679 * Wait until avail_min data becomes available
1680 * Returns a negative error code if any error occurs during operation.
1681 * The available space is stored on availp. When err = 0 and avail = 0
1682 * on the capture stream, it indicates the stream is in DRAINING state.
1684 static int wait_for_avail_min(struct snd_pcm_substream *substream,
1685 snd_pcm_uframes_t *availp)
1687 struct snd_pcm_runtime *runtime = substream->runtime;
1688 int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1691 snd_pcm_uframes_t avail = 0;
1694 init_waitqueue_entry(&wait, current);
1695 add_wait_queue(&runtime->sleep, &wait);
1697 if (signal_pending(current)) {
1701 set_current_state(TASK_INTERRUPTIBLE);
1702 snd_pcm_stream_unlock_irq(substream);
1703 tout = schedule_timeout(msecs_to_jiffies(10000));
1704 snd_pcm_stream_lock_irq(substream);
1705 switch (runtime->status->state) {
1706 case SNDRV_PCM_STATE_SUSPENDED:
1709 case SNDRV_PCM_STATE_XRUN:
1712 case SNDRV_PCM_STATE_DRAINING:
1716 avail = 0; /* indicate draining */
1718 case SNDRV_PCM_STATE_OPEN:
1719 case SNDRV_PCM_STATE_SETUP:
1720 case SNDRV_PCM_STATE_DISCONNECTED:
1725 snd_printd("%s write error (DMA or IRQ trouble?)\n",
1726 is_playback ? "playback" : "capture");
1731 avail = snd_pcm_playback_avail(runtime);
1733 avail = snd_pcm_capture_avail(runtime);
1734 if (avail >= runtime->control->avail_min)
1738 remove_wait_queue(&runtime->sleep, &wait);
1743 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1745 unsigned long data, unsigned int off,
1746 snd_pcm_uframes_t frames)
1748 struct snd_pcm_runtime *runtime = substream->runtime;
1750 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1751 if (substream->ops->copy) {
1752 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1755 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1756 if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1762 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1763 unsigned long data, unsigned int off,
1764 snd_pcm_uframes_t size);
1766 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1768 snd_pcm_uframes_t size,
1770 transfer_f transfer)
1772 struct snd_pcm_runtime *runtime = substream->runtime;
1773 snd_pcm_uframes_t xfer = 0;
1774 snd_pcm_uframes_t offset = 0;
1780 snd_pcm_stream_lock_irq(substream);
1781 switch (runtime->status->state) {
1782 case SNDRV_PCM_STATE_PREPARED:
1783 case SNDRV_PCM_STATE_RUNNING:
1784 case SNDRV_PCM_STATE_PAUSED:
1786 case SNDRV_PCM_STATE_XRUN:
1789 case SNDRV_PCM_STATE_SUSPENDED:
1797 runtime->nowake = 1;
1799 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1800 snd_pcm_uframes_t avail;
1801 snd_pcm_uframes_t cont;
1802 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1803 snd_pcm_update_hw_ptr(substream);
1804 avail = snd_pcm_playback_avail(runtime);
1810 err = wait_for_avail_min(substream, &avail);
1814 frames = size > avail ? avail : size;
1815 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1818 if (snd_BUG_ON(!frames)) {
1819 runtime->nowake = 0;
1820 snd_pcm_stream_unlock_irq(substream);
1823 appl_ptr = runtime->control->appl_ptr;
1824 appl_ofs = appl_ptr % runtime->buffer_size;
1825 snd_pcm_stream_unlock_irq(substream);
1826 err = transfer(substream, appl_ofs, data, offset, frames);
1827 snd_pcm_stream_lock_irq(substream);
1830 switch (runtime->status->state) {
1831 case SNDRV_PCM_STATE_XRUN:
1834 case SNDRV_PCM_STATE_SUSPENDED:
1841 if (appl_ptr >= runtime->boundary)
1842 appl_ptr -= runtime->boundary;
1843 runtime->control->appl_ptr = appl_ptr;
1844 if (substream->ops->ack)
1845 substream->ops->ack(substream);
1850 if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1851 snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1852 err = snd_pcm_start(substream);
1858 runtime->nowake = 0;
1859 if (xfer > 0 && err >= 0)
1860 snd_pcm_update_state(substream, runtime);
1861 snd_pcm_stream_unlock_irq(substream);
1862 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
1865 /* sanity-check for read/write methods */
1866 static int pcm_sanity_check(struct snd_pcm_substream *substream)
1868 struct snd_pcm_runtime *runtime;
1869 if (PCM_RUNTIME_CHECK(substream))
1871 runtime = substream->runtime;
1872 if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
1874 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1879 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
1881 struct snd_pcm_runtime *runtime;
1885 err = pcm_sanity_check(substream);
1888 runtime = substream->runtime;
1889 nonblock = !!(substream->f_flags & O_NONBLOCK);
1891 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
1892 runtime->channels > 1)
1894 return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
1895 snd_pcm_lib_write_transfer);
1898 EXPORT_SYMBOL(snd_pcm_lib_write);
1900 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
1902 unsigned long data, unsigned int off,
1903 snd_pcm_uframes_t frames)
1905 struct snd_pcm_runtime *runtime = substream->runtime;
1907 void __user **bufs = (void __user **)data;
1908 int channels = runtime->channels;
1910 if (substream->ops->copy) {
1911 if (snd_BUG_ON(!substream->ops->silence))
1913 for (c = 0; c < channels; ++c, ++bufs) {
1914 if (*bufs == NULL) {
1915 if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
1918 char __user *buf = *bufs + samples_to_bytes(runtime, off);
1919 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
1924 /* default transfer behaviour */
1925 size_t dma_csize = runtime->dma_bytes / channels;
1926 for (c = 0; c < channels; ++c, ++bufs) {
1927 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
1928 if (*bufs == NULL) {
1929 snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
1931 char __user *buf = *bufs + samples_to_bytes(runtime, off);
1932 if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
1940 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
1942 snd_pcm_uframes_t frames)
1944 struct snd_pcm_runtime *runtime;
1948 err = pcm_sanity_check(substream);
1951 runtime = substream->runtime;
1952 nonblock = !!(substream->f_flags & O_NONBLOCK);
1954 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
1956 return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
1957 nonblock, snd_pcm_lib_writev_transfer);
1960 EXPORT_SYMBOL(snd_pcm_lib_writev);
1962 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
1964 unsigned long data, unsigned int off,
1965 snd_pcm_uframes_t frames)
1967 struct snd_pcm_runtime *runtime = substream->runtime;
1969 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1970 if (substream->ops->copy) {
1971 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1974 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1975 if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
1981 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
1983 snd_pcm_uframes_t size,
1985 transfer_f transfer)
1987 struct snd_pcm_runtime *runtime = substream->runtime;
1988 snd_pcm_uframes_t xfer = 0;
1989 snd_pcm_uframes_t offset = 0;
1995 snd_pcm_stream_lock_irq(substream);
1996 switch (runtime->status->state) {
1997 case SNDRV_PCM_STATE_PREPARED:
1998 if (size >= runtime->start_threshold) {
1999 err = snd_pcm_start(substream);
2004 case SNDRV_PCM_STATE_DRAINING:
2005 case SNDRV_PCM_STATE_RUNNING:
2006 case SNDRV_PCM_STATE_PAUSED:
2008 case SNDRV_PCM_STATE_XRUN:
2011 case SNDRV_PCM_STATE_SUSPENDED:
2019 runtime->nowake = 1;
2021 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2022 snd_pcm_uframes_t avail;
2023 snd_pcm_uframes_t cont;
2024 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2025 snd_pcm_update_hw_ptr(substream);
2026 avail = snd_pcm_capture_avail(runtime);
2028 if (runtime->status->state ==
2029 SNDRV_PCM_STATE_DRAINING) {
2030 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2037 err = wait_for_avail_min(substream, &avail);
2041 continue; /* draining */
2043 frames = size > avail ? avail : size;
2044 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2047 if (snd_BUG_ON(!frames)) {
2048 runtime->nowake = 0;
2049 snd_pcm_stream_unlock_irq(substream);
2052 appl_ptr = runtime->control->appl_ptr;
2053 appl_ofs = appl_ptr % runtime->buffer_size;
2054 snd_pcm_stream_unlock_irq(substream);
2055 err = transfer(substream, appl_ofs, data, offset, frames);
2056 snd_pcm_stream_lock_irq(substream);
2059 switch (runtime->status->state) {
2060 case SNDRV_PCM_STATE_XRUN:
2063 case SNDRV_PCM_STATE_SUSPENDED:
2070 if (appl_ptr >= runtime->boundary)
2071 appl_ptr -= runtime->boundary;
2072 runtime->control->appl_ptr = appl_ptr;
2073 if (substream->ops->ack)
2074 substream->ops->ack(substream);
2081 runtime->nowake = 0;
2082 if (xfer > 0 && err >= 0)
2083 snd_pcm_update_state(substream, runtime);
2084 snd_pcm_stream_unlock_irq(substream);
2085 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2088 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2090 struct snd_pcm_runtime *runtime;
2094 err = pcm_sanity_check(substream);
2097 runtime = substream->runtime;
2098 nonblock = !!(substream->f_flags & O_NONBLOCK);
2099 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2101 return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2104 EXPORT_SYMBOL(snd_pcm_lib_read);
2106 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2108 unsigned long data, unsigned int off,
2109 snd_pcm_uframes_t frames)
2111 struct snd_pcm_runtime *runtime = substream->runtime;
2113 void __user **bufs = (void __user **)data;
2114 int channels = runtime->channels;
2116 if (substream->ops->copy) {
2117 for (c = 0; c < channels; ++c, ++bufs) {
2121 buf = *bufs + samples_to_bytes(runtime, off);
2122 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2126 snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2127 for (c = 0; c < channels; ++c, ++bufs) {
2133 hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2134 buf = *bufs + samples_to_bytes(runtime, off);
2135 if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2142 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2144 snd_pcm_uframes_t frames)
2146 struct snd_pcm_runtime *runtime;
2150 err = pcm_sanity_check(substream);
2153 runtime = substream->runtime;
2154 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2157 nonblock = !!(substream->f_flags & O_NONBLOCK);
2158 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2160 return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2163 EXPORT_SYMBOL(snd_pcm_lib_readv);