fs: use kmem_cache_zalloc instead
[pv_ops_mirror.git] / sound / core / pcm_lib.c
blob806f1fba5446d1f639309d203f55d2de2db268cc
1 /*
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 <sound/driver.h>
24 #include <linux/slab.h>
25 #include <linux/time.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;
51 if (n < 0)
52 n += runtime->boundary;
53 if ((snd_pcm_uframes_t)n < runtime->silence_filled)
54 runtime->silence_filled -= n;
55 else
56 runtime->silence_filled = 0;
57 runtime->silence_start = runtime->control->appl_ptr;
59 if (runtime->silence_filled >= runtime->buffer_size)
60 return;
61 noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
62 if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
63 return;
64 frames = runtime->silence_threshold - noise_dist;
65 if (frames > runtime->silence_size)
66 frames = runtime->silence_size;
67 } else {
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) %
73 runtime->boundary;
74 } else {
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;
83 } else {
84 runtime->silence_start = ofs;
87 frames = runtime->buffer_size - runtime->silence_filled;
89 snd_assert(frames <= runtime->buffer_size, return);
90 if (frames == 0)
91 return;
92 ofs = runtime->silence_start % runtime->buffer_size;
93 while (frames > 0) {
94 transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
95 if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
96 runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
97 if (substream->ops->silence) {
98 int err;
99 err = substream->ops->silence(substream, -1, ofs, transfer);
100 snd_assert(err >= 0, );
101 } else {
102 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
103 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
105 } else {
106 unsigned int c;
107 unsigned int channels = runtime->channels;
108 if (substream->ops->silence) {
109 for (c = 0; c < channels; ++c) {
110 int err;
111 err = substream->ops->silence(substream, c, ofs, transfer);
112 snd_assert(err >= 0, );
114 } else {
115 size_t dma_csize = runtime->dma_bytes / channels;
116 for (c = 0; c < channels; ++c) {
117 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
118 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
122 runtime->silence_filled += transfer;
123 frames -= transfer;
124 ofs = 0;
128 static void xrun(struct snd_pcm_substream *substream)
130 snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
131 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
132 if (substream->pstr->xrun_debug) {
133 snd_printd(KERN_DEBUG "XRUN: pcmC%dD%d%c\n",
134 substream->pcm->card->number,
135 substream->pcm->device,
136 substream->stream ? 'c' : 'p');
137 if (substream->pstr->xrun_debug > 1)
138 dump_stack();
140 #endif
143 static inline snd_pcm_uframes_t snd_pcm_update_hw_ptr_pos(struct snd_pcm_substream *substream,
144 struct snd_pcm_runtime *runtime)
146 snd_pcm_uframes_t pos;
148 pos = substream->ops->pointer(substream);
149 if (pos == SNDRV_PCM_POS_XRUN)
150 return pos; /* XRUN */
151 if (runtime->tstamp_mode & SNDRV_PCM_TSTAMP_MMAP)
152 getnstimeofday((struct timespec *)&runtime->status->tstamp);
153 #ifdef CONFIG_SND_DEBUG
154 if (pos >= runtime->buffer_size) {
155 snd_printk(KERN_ERR "BUG: stream = %i, pos = 0x%lx, buffer size = 0x%lx, period size = 0x%lx\n", substream->stream, pos, runtime->buffer_size, runtime->period_size);
157 #endif
158 pos -= pos % runtime->min_align;
159 return pos;
162 static inline int snd_pcm_update_hw_ptr_post(struct snd_pcm_substream *substream,
163 struct snd_pcm_runtime *runtime)
165 snd_pcm_uframes_t avail;
167 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
168 avail = snd_pcm_playback_avail(runtime);
169 else
170 avail = snd_pcm_capture_avail(runtime);
171 if (avail > runtime->avail_max)
172 runtime->avail_max = avail;
173 if (avail >= runtime->stop_threshold) {
174 if (substream->runtime->status->state == SNDRV_PCM_STATE_DRAINING)
175 snd_pcm_drain_done(substream);
176 else
177 xrun(substream);
178 return -EPIPE;
180 if (avail >= runtime->control->avail_min)
181 wake_up(&runtime->sleep);
182 return 0;
185 static inline int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream)
187 struct snd_pcm_runtime *runtime = substream->runtime;
188 snd_pcm_uframes_t pos;
189 snd_pcm_uframes_t new_hw_ptr, hw_ptr_interrupt;
190 snd_pcm_sframes_t delta;
192 pos = snd_pcm_update_hw_ptr_pos(substream, runtime);
193 if (pos == SNDRV_PCM_POS_XRUN) {
194 xrun(substream);
195 return -EPIPE;
197 if (runtime->period_size == runtime->buffer_size)
198 goto __next_buf;
199 new_hw_ptr = runtime->hw_ptr_base + pos;
200 hw_ptr_interrupt = runtime->hw_ptr_interrupt + runtime->period_size;
202 delta = hw_ptr_interrupt - new_hw_ptr;
203 if (delta > 0) {
204 if ((snd_pcm_uframes_t)delta < runtime->buffer_size / 2) {
205 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
206 if (runtime->periods > 1 && substream->pstr->xrun_debug) {
207 snd_printd(KERN_ERR "Unexpected hw_pointer value [1] (stream = %i, delta: -%ld, max jitter = %ld): wrong interrupt acknowledge?\n", substream->stream, (long) delta, runtime->buffer_size / 2);
208 if (substream->pstr->xrun_debug > 1)
209 dump_stack();
211 #endif
212 return 0;
214 __next_buf:
215 runtime->hw_ptr_base += runtime->buffer_size;
216 if (runtime->hw_ptr_base == runtime->boundary)
217 runtime->hw_ptr_base = 0;
218 new_hw_ptr = runtime->hw_ptr_base + pos;
221 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
222 runtime->silence_size > 0)
223 snd_pcm_playback_silence(substream, new_hw_ptr);
225 runtime->status->hw_ptr = new_hw_ptr;
226 runtime->hw_ptr_interrupt = new_hw_ptr - new_hw_ptr % runtime->period_size;
228 return snd_pcm_update_hw_ptr_post(substream, runtime);
231 /* CAUTION: call it with irq disabled */
232 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
234 struct snd_pcm_runtime *runtime = substream->runtime;
235 snd_pcm_uframes_t pos;
236 snd_pcm_uframes_t old_hw_ptr, new_hw_ptr;
237 snd_pcm_sframes_t delta;
239 old_hw_ptr = runtime->status->hw_ptr;
240 pos = snd_pcm_update_hw_ptr_pos(substream, runtime);
241 if (pos == SNDRV_PCM_POS_XRUN) {
242 xrun(substream);
243 return -EPIPE;
245 new_hw_ptr = runtime->hw_ptr_base + pos;
247 delta = old_hw_ptr - new_hw_ptr;
248 if (delta > 0) {
249 if ((snd_pcm_uframes_t)delta < runtime->buffer_size / 2) {
250 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
251 if (runtime->periods > 2 && substream->pstr->xrun_debug) {
252 snd_printd(KERN_ERR "Unexpected hw_pointer value [2] (stream = %i, delta: -%ld, max jitter = %ld): wrong interrupt acknowledge?\n", substream->stream, (long) delta, runtime->buffer_size / 2);
253 if (substream->pstr->xrun_debug > 1)
254 dump_stack();
256 #endif
257 return 0;
259 runtime->hw_ptr_base += runtime->buffer_size;
260 if (runtime->hw_ptr_base == runtime->boundary)
261 runtime->hw_ptr_base = 0;
262 new_hw_ptr = runtime->hw_ptr_base + pos;
264 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
265 runtime->silence_size > 0)
266 snd_pcm_playback_silence(substream, new_hw_ptr);
268 runtime->status->hw_ptr = new_hw_ptr;
270 return snd_pcm_update_hw_ptr_post(substream, runtime);
274 * snd_pcm_set_ops - set the PCM operators
275 * @pcm: the pcm instance
276 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
277 * @ops: the operator table
279 * Sets the given PCM operators to the pcm instance.
281 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction, struct snd_pcm_ops *ops)
283 struct snd_pcm_str *stream = &pcm->streams[direction];
284 struct snd_pcm_substream *substream;
286 for (substream = stream->substream; substream != NULL; substream = substream->next)
287 substream->ops = ops;
290 EXPORT_SYMBOL(snd_pcm_set_ops);
293 * snd_pcm_sync - set the PCM sync id
294 * @substream: the pcm substream
296 * Sets the PCM sync identifier for the card.
298 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
300 struct snd_pcm_runtime *runtime = substream->runtime;
302 runtime->sync.id32[0] = substream->pcm->card->number;
303 runtime->sync.id32[1] = -1;
304 runtime->sync.id32[2] = -1;
305 runtime->sync.id32[3] = -1;
308 EXPORT_SYMBOL(snd_pcm_set_sync);
311 * Standard ioctl routine
314 static inline unsigned int div32(unsigned int a, unsigned int b,
315 unsigned int *r)
317 if (b == 0) {
318 *r = 0;
319 return UINT_MAX;
321 *r = a % b;
322 return a / b;
325 static inline unsigned int div_down(unsigned int a, unsigned int b)
327 if (b == 0)
328 return UINT_MAX;
329 return a / b;
332 static inline unsigned int div_up(unsigned int a, unsigned int b)
334 unsigned int r;
335 unsigned int q;
336 if (b == 0)
337 return UINT_MAX;
338 q = div32(a, b, &r);
339 if (r)
340 ++q;
341 return q;
344 static inline unsigned int mul(unsigned int a, unsigned int b)
346 if (a == 0)
347 return 0;
348 if (div_down(UINT_MAX, a) < b)
349 return UINT_MAX;
350 return a * b;
353 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
354 unsigned int c, unsigned int *r)
356 u_int64_t n = (u_int64_t) a * b;
357 if (c == 0) {
358 snd_assert(n > 0, );
359 *r = 0;
360 return UINT_MAX;
362 div64_32(&n, c, r);
363 if (n >= UINT_MAX) {
364 *r = 0;
365 return UINT_MAX;
367 return n;
371 * snd_interval_refine - refine the interval value of configurator
372 * @i: the interval value to refine
373 * @v: the interval value to refer to
375 * Refines the interval value with the reference value.
376 * The interval is changed to the range satisfying both intervals.
377 * The interval status (min, max, integer, etc.) are evaluated.
379 * Returns non-zero if the value is changed, zero if not changed.
381 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
383 int changed = 0;
384 snd_assert(!snd_interval_empty(i), return -EINVAL);
385 if (i->min < v->min) {
386 i->min = v->min;
387 i->openmin = v->openmin;
388 changed = 1;
389 } else if (i->min == v->min && !i->openmin && v->openmin) {
390 i->openmin = 1;
391 changed = 1;
393 if (i->max > v->max) {
394 i->max = v->max;
395 i->openmax = v->openmax;
396 changed = 1;
397 } else if (i->max == v->max && !i->openmax && v->openmax) {
398 i->openmax = 1;
399 changed = 1;
401 if (!i->integer && v->integer) {
402 i->integer = 1;
403 changed = 1;
405 if (i->integer) {
406 if (i->openmin) {
407 i->min++;
408 i->openmin = 0;
410 if (i->openmax) {
411 i->max--;
412 i->openmax = 0;
414 } else if (!i->openmin && !i->openmax && i->min == i->max)
415 i->integer = 1;
416 if (snd_interval_checkempty(i)) {
417 snd_interval_none(i);
418 return -EINVAL;
420 return changed;
423 EXPORT_SYMBOL(snd_interval_refine);
425 static int snd_interval_refine_first(struct snd_interval *i)
427 snd_assert(!snd_interval_empty(i), return -EINVAL);
428 if (snd_interval_single(i))
429 return 0;
430 i->max = i->min;
431 i->openmax = i->openmin;
432 if (i->openmax)
433 i->max++;
434 return 1;
437 static int snd_interval_refine_last(struct snd_interval *i)
439 snd_assert(!snd_interval_empty(i), return -EINVAL);
440 if (snd_interval_single(i))
441 return 0;
442 i->min = i->max;
443 i->openmin = i->openmax;
444 if (i->openmin)
445 i->min--;
446 return 1;
449 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
451 if (a->empty || b->empty) {
452 snd_interval_none(c);
453 return;
455 c->empty = 0;
456 c->min = mul(a->min, b->min);
457 c->openmin = (a->openmin || b->openmin);
458 c->max = mul(a->max, b->max);
459 c->openmax = (a->openmax || b->openmax);
460 c->integer = (a->integer && b->integer);
464 * snd_interval_div - refine the interval value with division
465 * @a: dividend
466 * @b: divisor
467 * @c: quotient
469 * c = a / b
471 * Returns non-zero if the value is changed, zero if not changed.
473 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
475 unsigned int r;
476 if (a->empty || b->empty) {
477 snd_interval_none(c);
478 return;
480 c->empty = 0;
481 c->min = div32(a->min, b->max, &r);
482 c->openmin = (r || a->openmin || b->openmax);
483 if (b->min > 0) {
484 c->max = div32(a->max, b->min, &r);
485 if (r) {
486 c->max++;
487 c->openmax = 1;
488 } else
489 c->openmax = (a->openmax || b->openmin);
490 } else {
491 c->max = UINT_MAX;
492 c->openmax = 0;
494 c->integer = 0;
498 * snd_interval_muldivk - refine the interval value
499 * @a: dividend 1
500 * @b: dividend 2
501 * @k: divisor (as integer)
502 * @c: result
504 * c = a * b / k
506 * Returns non-zero if the value is changed, zero if not changed.
508 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
509 unsigned int k, struct snd_interval *c)
511 unsigned int r;
512 if (a->empty || b->empty) {
513 snd_interval_none(c);
514 return;
516 c->empty = 0;
517 c->min = muldiv32(a->min, b->min, k, &r);
518 c->openmin = (r || a->openmin || b->openmin);
519 c->max = muldiv32(a->max, b->max, k, &r);
520 if (r) {
521 c->max++;
522 c->openmax = 1;
523 } else
524 c->openmax = (a->openmax || b->openmax);
525 c->integer = 0;
529 * snd_interval_mulkdiv - refine the interval value
530 * @a: dividend 1
531 * @k: dividend 2 (as integer)
532 * @b: divisor
533 * @c: result
535 * c = a * k / b
537 * Returns non-zero if the value is changed, zero if not changed.
539 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
540 const struct snd_interval *b, struct snd_interval *c)
542 unsigned int r;
543 if (a->empty || b->empty) {
544 snd_interval_none(c);
545 return;
547 c->empty = 0;
548 c->min = muldiv32(a->min, k, b->max, &r);
549 c->openmin = (r || a->openmin || b->openmax);
550 if (b->min > 0) {
551 c->max = muldiv32(a->max, k, b->min, &r);
552 if (r) {
553 c->max++;
554 c->openmax = 1;
555 } else
556 c->openmax = (a->openmax || b->openmin);
557 } else {
558 c->max = UINT_MAX;
559 c->openmax = 0;
561 c->integer = 0;
564 /* ---- */
568 * snd_interval_ratnum - refine the interval value
569 * @i: interval to refine
570 * @rats_count: number of ratnum_t
571 * @rats: ratnum_t array
572 * @nump: pointer to store the resultant numerator
573 * @denp: pointer to store the resultant denominator
575 * Returns non-zero if the value is changed, zero if not changed.
577 int snd_interval_ratnum(struct snd_interval *i,
578 unsigned int rats_count, struct snd_ratnum *rats,
579 unsigned int *nump, unsigned int *denp)
581 unsigned int best_num, best_diff, best_den;
582 unsigned int k;
583 struct snd_interval t;
584 int err;
586 best_num = best_den = best_diff = 0;
587 for (k = 0; k < rats_count; ++k) {
588 unsigned int num = rats[k].num;
589 unsigned int den;
590 unsigned int q = i->min;
591 int diff;
592 if (q == 0)
593 q = 1;
594 den = div_down(num, q);
595 if (den < rats[k].den_min)
596 continue;
597 if (den > rats[k].den_max)
598 den = rats[k].den_max;
599 else {
600 unsigned int r;
601 r = (den - rats[k].den_min) % rats[k].den_step;
602 if (r != 0)
603 den -= r;
605 diff = num - q * den;
606 if (best_num == 0 ||
607 diff * best_den < best_diff * den) {
608 best_diff = diff;
609 best_den = den;
610 best_num = num;
613 if (best_den == 0) {
614 i->empty = 1;
615 return -EINVAL;
617 t.min = div_down(best_num, best_den);
618 t.openmin = !!(best_num % best_den);
620 best_num = best_den = best_diff = 0;
621 for (k = 0; k < rats_count; ++k) {
622 unsigned int num = rats[k].num;
623 unsigned int den;
624 unsigned int q = i->max;
625 int diff;
626 if (q == 0) {
627 i->empty = 1;
628 return -EINVAL;
630 den = div_up(num, q);
631 if (den > rats[k].den_max)
632 continue;
633 if (den < rats[k].den_min)
634 den = rats[k].den_min;
635 else {
636 unsigned int r;
637 r = (den - rats[k].den_min) % rats[k].den_step;
638 if (r != 0)
639 den += rats[k].den_step - r;
641 diff = q * den - num;
642 if (best_num == 0 ||
643 diff * best_den < best_diff * den) {
644 best_diff = diff;
645 best_den = den;
646 best_num = num;
649 if (best_den == 0) {
650 i->empty = 1;
651 return -EINVAL;
653 t.max = div_up(best_num, best_den);
654 t.openmax = !!(best_num % best_den);
655 t.integer = 0;
656 err = snd_interval_refine(i, &t);
657 if (err < 0)
658 return err;
660 if (snd_interval_single(i)) {
661 if (nump)
662 *nump = best_num;
663 if (denp)
664 *denp = best_den;
666 return err;
669 EXPORT_SYMBOL(snd_interval_ratnum);
672 * snd_interval_ratden - refine the interval value
673 * @i: interval to refine
674 * @rats_count: number of struct ratden
675 * @rats: struct ratden array
676 * @nump: pointer to store the resultant numerator
677 * @denp: pointer to store the resultant denominator
679 * Returns non-zero if the value is changed, zero if not changed.
681 static int snd_interval_ratden(struct snd_interval *i,
682 unsigned int rats_count, struct snd_ratden *rats,
683 unsigned int *nump, unsigned int *denp)
685 unsigned int best_num, best_diff, best_den;
686 unsigned int k;
687 struct snd_interval t;
688 int err;
690 best_num = best_den = best_diff = 0;
691 for (k = 0; k < rats_count; ++k) {
692 unsigned int num;
693 unsigned int den = rats[k].den;
694 unsigned int q = i->min;
695 int diff;
696 num = mul(q, den);
697 if (num > rats[k].num_max)
698 continue;
699 if (num < rats[k].num_min)
700 num = rats[k].num_max;
701 else {
702 unsigned int r;
703 r = (num - rats[k].num_min) % rats[k].num_step;
704 if (r != 0)
705 num += rats[k].num_step - r;
707 diff = num - q * den;
708 if (best_num == 0 ||
709 diff * best_den < best_diff * den) {
710 best_diff = diff;
711 best_den = den;
712 best_num = num;
715 if (best_den == 0) {
716 i->empty = 1;
717 return -EINVAL;
719 t.min = div_down(best_num, best_den);
720 t.openmin = !!(best_num % best_den);
722 best_num = best_den = best_diff = 0;
723 for (k = 0; k < rats_count; ++k) {
724 unsigned int num;
725 unsigned int den = rats[k].den;
726 unsigned int q = i->max;
727 int diff;
728 num = mul(q, den);
729 if (num < rats[k].num_min)
730 continue;
731 if (num > rats[k].num_max)
732 num = rats[k].num_max;
733 else {
734 unsigned int r;
735 r = (num - rats[k].num_min) % rats[k].num_step;
736 if (r != 0)
737 num -= r;
739 diff = q * den - num;
740 if (best_num == 0 ||
741 diff * best_den < best_diff * den) {
742 best_diff = diff;
743 best_den = den;
744 best_num = num;
747 if (best_den == 0) {
748 i->empty = 1;
749 return -EINVAL;
751 t.max = div_up(best_num, best_den);
752 t.openmax = !!(best_num % best_den);
753 t.integer = 0;
754 err = snd_interval_refine(i, &t);
755 if (err < 0)
756 return err;
758 if (snd_interval_single(i)) {
759 if (nump)
760 *nump = best_num;
761 if (denp)
762 *denp = best_den;
764 return err;
768 * snd_interval_list - refine the interval value from the list
769 * @i: the interval value to refine
770 * @count: the number of elements in the list
771 * @list: the value list
772 * @mask: the bit-mask to evaluate
774 * Refines the interval value from the list.
775 * When mask is non-zero, only the elements corresponding to bit 1 are
776 * evaluated.
778 * Returns non-zero if the value is changed, zero if not changed.
780 int snd_interval_list(struct snd_interval *i, unsigned int count, unsigned int *list, unsigned int mask)
782 unsigned int k;
783 int changed = 0;
785 if (!count) {
786 i->empty = 1;
787 return -EINVAL;
789 for (k = 0; k < count; k++) {
790 if (mask && !(mask & (1 << k)))
791 continue;
792 if (i->min == list[k] && !i->openmin)
793 goto _l1;
794 if (i->min < list[k]) {
795 i->min = list[k];
796 i->openmin = 0;
797 changed = 1;
798 goto _l1;
801 i->empty = 1;
802 return -EINVAL;
803 _l1:
804 for (k = count; k-- > 0;) {
805 if (mask && !(mask & (1 << k)))
806 continue;
807 if (i->max == list[k] && !i->openmax)
808 goto _l2;
809 if (i->max > list[k]) {
810 i->max = list[k];
811 i->openmax = 0;
812 changed = 1;
813 goto _l2;
816 i->empty = 1;
817 return -EINVAL;
818 _l2:
819 if (snd_interval_checkempty(i)) {
820 i->empty = 1;
821 return -EINVAL;
823 return changed;
826 EXPORT_SYMBOL(snd_interval_list);
828 static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
830 unsigned int n;
831 int changed = 0;
832 n = (i->min - min) % step;
833 if (n != 0 || i->openmin) {
834 i->min += step - n;
835 changed = 1;
837 n = (i->max - min) % step;
838 if (n != 0 || i->openmax) {
839 i->max -= n;
840 changed = 1;
842 if (snd_interval_checkempty(i)) {
843 i->empty = 1;
844 return -EINVAL;
846 return changed;
849 /* Info constraints helpers */
852 * snd_pcm_hw_rule_add - add the hw-constraint rule
853 * @runtime: the pcm runtime instance
854 * @cond: condition bits
855 * @var: the variable to evaluate
856 * @func: the evaluation function
857 * @private: the private data pointer passed to function
858 * @dep: the dependent variables
860 * Returns zero if successful, or a negative error code on failure.
862 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
863 int var,
864 snd_pcm_hw_rule_func_t func, void *private,
865 int dep, ...)
867 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
868 struct snd_pcm_hw_rule *c;
869 unsigned int k;
870 va_list args;
871 va_start(args, dep);
872 if (constrs->rules_num >= constrs->rules_all) {
873 struct snd_pcm_hw_rule *new;
874 unsigned int new_rules = constrs->rules_all + 16;
875 new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
876 if (!new)
877 return -ENOMEM;
878 if (constrs->rules) {
879 memcpy(new, constrs->rules,
880 constrs->rules_num * sizeof(*c));
881 kfree(constrs->rules);
883 constrs->rules = new;
884 constrs->rules_all = new_rules;
886 c = &constrs->rules[constrs->rules_num];
887 c->cond = cond;
888 c->func = func;
889 c->var = var;
890 c->private = private;
891 k = 0;
892 while (1) {
893 snd_assert(k < ARRAY_SIZE(c->deps), return -EINVAL);
894 c->deps[k++] = dep;
895 if (dep < 0)
896 break;
897 dep = va_arg(args, int);
899 constrs->rules_num++;
900 va_end(args);
901 return 0;
904 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
907 * snd_pcm_hw_constraint_mask
908 * @runtime: PCM runtime instance
909 * @var: hw_params variable to apply the mask
910 * @mask: the bitmap mask
912 * Apply the constraint of the given bitmap mask to a mask parameter.
914 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
915 u_int32_t mask)
917 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
918 struct snd_mask *maskp = constrs_mask(constrs, var);
919 *maskp->bits &= mask;
920 memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
921 if (*maskp->bits == 0)
922 return -EINVAL;
923 return 0;
927 * snd_pcm_hw_constraint_mask64
928 * @runtime: PCM runtime instance
929 * @var: hw_params variable to apply the mask
930 * @mask: the 64bit bitmap mask
932 * Apply the constraint of the given bitmap mask to a mask parameter.
934 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
935 u_int64_t mask)
937 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
938 struct snd_mask *maskp = constrs_mask(constrs, var);
939 maskp->bits[0] &= (u_int32_t)mask;
940 maskp->bits[1] &= (u_int32_t)(mask >> 32);
941 memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
942 if (! maskp->bits[0] && ! maskp->bits[1])
943 return -EINVAL;
944 return 0;
948 * snd_pcm_hw_constraint_integer
949 * @runtime: PCM runtime instance
950 * @var: hw_params variable to apply the integer constraint
952 * Apply the constraint of integer to an interval parameter.
954 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
956 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
957 return snd_interval_setinteger(constrs_interval(constrs, var));
960 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
963 * snd_pcm_hw_constraint_minmax
964 * @runtime: PCM runtime instance
965 * @var: hw_params variable to apply the range
966 * @min: the minimal value
967 * @max: the maximal value
969 * Apply the min/max range constraint to an interval parameter.
971 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
972 unsigned int min, unsigned int max)
974 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
975 struct snd_interval t;
976 t.min = min;
977 t.max = max;
978 t.openmin = t.openmax = 0;
979 t.integer = 0;
980 return snd_interval_refine(constrs_interval(constrs, var), &t);
983 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
985 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
986 struct snd_pcm_hw_rule *rule)
988 struct snd_pcm_hw_constraint_list *list = rule->private;
989 return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
994 * snd_pcm_hw_constraint_list
995 * @runtime: PCM runtime instance
996 * @cond: condition bits
997 * @var: hw_params variable to apply the list constraint
998 * @l: list
1000 * Apply the list of constraints to an interval parameter.
1002 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1003 unsigned int cond,
1004 snd_pcm_hw_param_t var,
1005 struct snd_pcm_hw_constraint_list *l)
1007 return snd_pcm_hw_rule_add(runtime, cond, var,
1008 snd_pcm_hw_rule_list, l,
1009 var, -1);
1012 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1014 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1015 struct snd_pcm_hw_rule *rule)
1017 struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1018 unsigned int num = 0, den = 0;
1019 int err;
1020 err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1021 r->nrats, r->rats, &num, &den);
1022 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1023 params->rate_num = num;
1024 params->rate_den = den;
1026 return err;
1030 * snd_pcm_hw_constraint_ratnums
1031 * @runtime: PCM runtime instance
1032 * @cond: condition bits
1033 * @var: hw_params variable to apply the ratnums constraint
1034 * @r: struct snd_ratnums constriants
1036 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1037 unsigned int cond,
1038 snd_pcm_hw_param_t var,
1039 struct snd_pcm_hw_constraint_ratnums *r)
1041 return snd_pcm_hw_rule_add(runtime, cond, var,
1042 snd_pcm_hw_rule_ratnums, r,
1043 var, -1);
1046 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1048 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1049 struct snd_pcm_hw_rule *rule)
1051 struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1052 unsigned int num = 0, den = 0;
1053 int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1054 r->nrats, r->rats, &num, &den);
1055 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1056 params->rate_num = num;
1057 params->rate_den = den;
1059 return err;
1063 * snd_pcm_hw_constraint_ratdens
1064 * @runtime: PCM runtime instance
1065 * @cond: condition bits
1066 * @var: hw_params variable to apply the ratdens constraint
1067 * @r: struct snd_ratdens constriants
1069 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1070 unsigned int cond,
1071 snd_pcm_hw_param_t var,
1072 struct snd_pcm_hw_constraint_ratdens *r)
1074 return snd_pcm_hw_rule_add(runtime, cond, var,
1075 snd_pcm_hw_rule_ratdens, r,
1076 var, -1);
1079 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1081 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1082 struct snd_pcm_hw_rule *rule)
1084 unsigned int l = (unsigned long) rule->private;
1085 int width = l & 0xffff;
1086 unsigned int msbits = l >> 16;
1087 struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1088 if (snd_interval_single(i) && snd_interval_value(i) == width)
1089 params->msbits = msbits;
1090 return 0;
1094 * snd_pcm_hw_constraint_msbits
1095 * @runtime: PCM runtime instance
1096 * @cond: condition bits
1097 * @width: sample bits width
1098 * @msbits: msbits width
1100 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1101 unsigned int cond,
1102 unsigned int width,
1103 unsigned int msbits)
1105 unsigned long l = (msbits << 16) | width;
1106 return snd_pcm_hw_rule_add(runtime, cond, -1,
1107 snd_pcm_hw_rule_msbits,
1108 (void*) l,
1109 SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1112 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1114 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1115 struct snd_pcm_hw_rule *rule)
1117 unsigned long step = (unsigned long) rule->private;
1118 return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1122 * snd_pcm_hw_constraint_step
1123 * @runtime: PCM runtime instance
1124 * @cond: condition bits
1125 * @var: hw_params variable to apply the step constraint
1126 * @step: step size
1128 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1129 unsigned int cond,
1130 snd_pcm_hw_param_t var,
1131 unsigned long step)
1133 return snd_pcm_hw_rule_add(runtime, cond, var,
1134 snd_pcm_hw_rule_step, (void *) step,
1135 var, -1);
1138 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1140 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1142 static int pow2_sizes[] = {
1143 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1144 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1145 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1146 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1148 return snd_interval_list(hw_param_interval(params, rule->var),
1149 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1153 * snd_pcm_hw_constraint_pow2
1154 * @runtime: PCM runtime instance
1155 * @cond: condition bits
1156 * @var: hw_params variable to apply the power-of-2 constraint
1158 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1159 unsigned int cond,
1160 snd_pcm_hw_param_t var)
1162 return snd_pcm_hw_rule_add(runtime, cond, var,
1163 snd_pcm_hw_rule_pow2, NULL,
1164 var, -1);
1167 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1169 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1170 snd_pcm_hw_param_t var)
1172 if (hw_is_mask(var)) {
1173 snd_mask_any(hw_param_mask(params, var));
1174 params->cmask |= 1 << var;
1175 params->rmask |= 1 << var;
1176 return;
1178 if (hw_is_interval(var)) {
1179 snd_interval_any(hw_param_interval(params, var));
1180 params->cmask |= 1 << var;
1181 params->rmask |= 1 << var;
1182 return;
1184 snd_BUG();
1187 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1189 unsigned int k;
1190 memset(params, 0, sizeof(*params));
1191 for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1192 _snd_pcm_hw_param_any(params, k);
1193 for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1194 _snd_pcm_hw_param_any(params, k);
1195 params->info = ~0U;
1198 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1201 * snd_pcm_hw_param_value
1202 * @params: the hw_params instance
1203 * @var: parameter to retrieve
1204 * @dir: pointer to the direction (-1,0,1) or NULL
1206 * Return the value for field PAR if it's fixed in configuration space
1207 * defined by PARAMS. Return -EINVAL otherwise
1209 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1210 snd_pcm_hw_param_t var, int *dir)
1212 if (hw_is_mask(var)) {
1213 const struct snd_mask *mask = hw_param_mask_c(params, var);
1214 if (!snd_mask_single(mask))
1215 return -EINVAL;
1216 if (dir)
1217 *dir = 0;
1218 return snd_mask_value(mask);
1220 if (hw_is_interval(var)) {
1221 const struct snd_interval *i = hw_param_interval_c(params, var);
1222 if (!snd_interval_single(i))
1223 return -EINVAL;
1224 if (dir)
1225 *dir = i->openmin;
1226 return snd_interval_value(i);
1228 return -EINVAL;
1231 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1233 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1234 snd_pcm_hw_param_t var)
1236 if (hw_is_mask(var)) {
1237 snd_mask_none(hw_param_mask(params, var));
1238 params->cmask |= 1 << var;
1239 params->rmask |= 1 << var;
1240 } else if (hw_is_interval(var)) {
1241 snd_interval_none(hw_param_interval(params, var));
1242 params->cmask |= 1 << var;
1243 params->rmask |= 1 << var;
1244 } else {
1245 snd_BUG();
1249 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1251 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1252 snd_pcm_hw_param_t var)
1254 int changed;
1255 if (hw_is_mask(var))
1256 changed = snd_mask_refine_first(hw_param_mask(params, var));
1257 else if (hw_is_interval(var))
1258 changed = snd_interval_refine_first(hw_param_interval(params, var));
1259 else
1260 return -EINVAL;
1261 if (changed) {
1262 params->cmask |= 1 << var;
1263 params->rmask |= 1 << var;
1265 return changed;
1270 * snd_pcm_hw_param_first
1271 * @pcm: PCM instance
1272 * @params: the hw_params instance
1273 * @var: parameter to retrieve
1274 * @dir: pointer to the direction (-1,0,1) or NULL
1276 * Inside configuration space defined by PARAMS remove from PAR all
1277 * values > minimum. Reduce configuration space accordingly.
1278 * Return the minimum.
1280 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1281 struct snd_pcm_hw_params *params,
1282 snd_pcm_hw_param_t var, int *dir)
1284 int changed = _snd_pcm_hw_param_first(params, var);
1285 if (changed < 0)
1286 return changed;
1287 if (params->rmask) {
1288 int err = snd_pcm_hw_refine(pcm, params);
1289 snd_assert(err >= 0, return err);
1291 return snd_pcm_hw_param_value(params, var, dir);
1294 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1296 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1297 snd_pcm_hw_param_t var)
1299 int changed;
1300 if (hw_is_mask(var))
1301 changed = snd_mask_refine_last(hw_param_mask(params, var));
1302 else if (hw_is_interval(var))
1303 changed = snd_interval_refine_last(hw_param_interval(params, var));
1304 else
1305 return -EINVAL;
1306 if (changed) {
1307 params->cmask |= 1 << var;
1308 params->rmask |= 1 << var;
1310 return changed;
1315 * snd_pcm_hw_param_last
1316 * @pcm: PCM instance
1317 * @params: the hw_params instance
1318 * @var: parameter to retrieve
1319 * @dir: pointer to the direction (-1,0,1) or NULL
1321 * Inside configuration space defined by PARAMS remove from PAR all
1322 * values < maximum. Reduce configuration space accordingly.
1323 * Return the maximum.
1325 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1326 struct snd_pcm_hw_params *params,
1327 snd_pcm_hw_param_t var, int *dir)
1329 int changed = _snd_pcm_hw_param_last(params, var);
1330 if (changed < 0)
1331 return changed;
1332 if (params->rmask) {
1333 int err = snd_pcm_hw_refine(pcm, params);
1334 snd_assert(err >= 0, return err);
1336 return snd_pcm_hw_param_value(params, var, dir);
1339 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1342 * snd_pcm_hw_param_choose
1343 * @pcm: PCM instance
1344 * @params: the hw_params instance
1346 * Choose one configuration from configuration space defined by PARAMS
1347 * The configuration chosen is that obtained fixing in this order:
1348 * first access, first format, first subformat, min channels,
1349 * min rate, min period time, max buffer size, min tick time
1351 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1352 struct snd_pcm_hw_params *params)
1354 static int vars[] = {
1355 SNDRV_PCM_HW_PARAM_ACCESS,
1356 SNDRV_PCM_HW_PARAM_FORMAT,
1357 SNDRV_PCM_HW_PARAM_SUBFORMAT,
1358 SNDRV_PCM_HW_PARAM_CHANNELS,
1359 SNDRV_PCM_HW_PARAM_RATE,
1360 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1361 SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1362 SNDRV_PCM_HW_PARAM_TICK_TIME,
1365 int err, *v;
1367 for (v = vars; *v != -1; v++) {
1368 if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1369 err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1370 else
1371 err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1372 snd_assert(err >= 0, return err);
1374 return 0;
1377 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1378 void *arg)
1380 struct snd_pcm_runtime *runtime = substream->runtime;
1381 unsigned long flags;
1382 snd_pcm_stream_lock_irqsave(substream, flags);
1383 if (snd_pcm_running(substream) &&
1384 snd_pcm_update_hw_ptr(substream) >= 0)
1385 runtime->status->hw_ptr %= runtime->buffer_size;
1386 else
1387 runtime->status->hw_ptr = 0;
1388 snd_pcm_stream_unlock_irqrestore(substream, flags);
1389 return 0;
1392 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1393 void *arg)
1395 struct snd_pcm_channel_info *info = arg;
1396 struct snd_pcm_runtime *runtime = substream->runtime;
1397 int width;
1398 if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1399 info->offset = -1;
1400 return 0;
1402 width = snd_pcm_format_physical_width(runtime->format);
1403 if (width < 0)
1404 return width;
1405 info->offset = 0;
1406 switch (runtime->access) {
1407 case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1408 case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1409 info->first = info->channel * width;
1410 info->step = runtime->channels * width;
1411 break;
1412 case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1413 case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1415 size_t size = runtime->dma_bytes / runtime->channels;
1416 info->first = info->channel * size * 8;
1417 info->step = width;
1418 break;
1420 default:
1421 snd_BUG();
1422 break;
1424 return 0;
1428 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1429 * @substream: the pcm substream instance
1430 * @cmd: ioctl command
1431 * @arg: ioctl argument
1433 * Processes the generic ioctl commands for PCM.
1434 * Can be passed as the ioctl callback for PCM ops.
1436 * Returns zero if successful, or a negative error code on failure.
1438 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1439 unsigned int cmd, void *arg)
1441 switch (cmd) {
1442 case SNDRV_PCM_IOCTL1_INFO:
1443 return 0;
1444 case SNDRV_PCM_IOCTL1_RESET:
1445 return snd_pcm_lib_ioctl_reset(substream, arg);
1446 case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1447 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1449 return -ENXIO;
1452 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1455 * Conditions
1458 static void snd_pcm_system_tick_set(struct snd_pcm_substream *substream,
1459 unsigned long ticks)
1461 struct snd_pcm_runtime *runtime = substream->runtime;
1462 if (ticks == 0)
1463 del_timer(&runtime->tick_timer);
1464 else {
1465 ticks += (1000000 / HZ) - 1;
1466 ticks /= (1000000 / HZ);
1467 mod_timer(&runtime->tick_timer, jiffies + ticks);
1471 /* Temporary alias */
1472 void snd_pcm_tick_set(struct snd_pcm_substream *substream, unsigned long ticks)
1474 snd_pcm_system_tick_set(substream, ticks);
1477 void snd_pcm_tick_prepare(struct snd_pcm_substream *substream)
1479 struct snd_pcm_runtime *runtime = substream->runtime;
1480 snd_pcm_uframes_t frames = ULONG_MAX;
1481 snd_pcm_uframes_t avail, dist;
1482 unsigned int ticks;
1483 u_int64_t n;
1484 u_int32_t r;
1485 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
1486 if (runtime->silence_size >= runtime->boundary) {
1487 frames = 1;
1488 } else if (runtime->silence_size > 0 &&
1489 runtime->silence_filled < runtime->buffer_size) {
1490 snd_pcm_sframes_t noise_dist;
1491 noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
1492 if (noise_dist > (snd_pcm_sframes_t)runtime->silence_threshold)
1493 frames = noise_dist - runtime->silence_threshold;
1495 avail = snd_pcm_playback_avail(runtime);
1496 } else {
1497 avail = snd_pcm_capture_avail(runtime);
1499 if (avail < runtime->control->avail_min) {
1500 snd_pcm_sframes_t n = runtime->control->avail_min - avail;
1501 if (n > 0 && frames > (snd_pcm_uframes_t)n)
1502 frames = n;
1504 if (avail < runtime->buffer_size) {
1505 snd_pcm_sframes_t n = runtime->buffer_size - avail;
1506 if (n > 0 && frames > (snd_pcm_uframes_t)n)
1507 frames = n;
1509 if (frames == ULONG_MAX) {
1510 snd_pcm_tick_set(substream, 0);
1511 return;
1513 dist = runtime->status->hw_ptr - runtime->hw_ptr_base;
1514 /* Distance to next interrupt */
1515 dist = runtime->period_size - dist % runtime->period_size;
1516 if (dist <= frames) {
1517 snd_pcm_tick_set(substream, 0);
1518 return;
1520 /* the base time is us */
1521 n = frames;
1522 n *= 1000000;
1523 div64_32(&n, runtime->tick_time * runtime->rate, &r);
1524 ticks = n + (r > 0 ? 1 : 0);
1525 if (ticks < runtime->sleep_min)
1526 ticks = runtime->sleep_min;
1527 snd_pcm_tick_set(substream, (unsigned long) ticks);
1530 void snd_pcm_tick_elapsed(struct snd_pcm_substream *substream)
1532 struct snd_pcm_runtime *runtime;
1533 unsigned long flags;
1535 snd_assert(substream != NULL, return);
1536 runtime = substream->runtime;
1537 snd_assert(runtime != NULL, return);
1539 snd_pcm_stream_lock_irqsave(substream, flags);
1540 if (!snd_pcm_running(substream) ||
1541 snd_pcm_update_hw_ptr(substream) < 0)
1542 goto _end;
1543 if (runtime->sleep_min)
1544 snd_pcm_tick_prepare(substream);
1545 _end:
1546 snd_pcm_stream_unlock_irqrestore(substream, flags);
1550 * snd_pcm_period_elapsed - update the pcm status for the next period
1551 * @substream: the pcm substream instance
1553 * This function is called from the interrupt handler when the
1554 * PCM has processed the period size. It will update the current
1555 * pointer, set up the tick, wake up sleepers, etc.
1557 * Even if more than one periods have elapsed since the last call, you
1558 * have to call this only once.
1560 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1562 struct snd_pcm_runtime *runtime;
1563 unsigned long flags;
1565 snd_assert(substream != NULL, return);
1566 runtime = substream->runtime;
1567 snd_assert(runtime != NULL, return);
1569 if (runtime->transfer_ack_begin)
1570 runtime->transfer_ack_begin(substream);
1572 snd_pcm_stream_lock_irqsave(substream, flags);
1573 if (!snd_pcm_running(substream) ||
1574 snd_pcm_update_hw_ptr_interrupt(substream) < 0)
1575 goto _end;
1577 if (substream->timer_running)
1578 snd_timer_interrupt(substream->timer, 1);
1579 if (runtime->sleep_min)
1580 snd_pcm_tick_prepare(substream);
1581 _end:
1582 snd_pcm_stream_unlock_irqrestore(substream, flags);
1583 if (runtime->transfer_ack_end)
1584 runtime->transfer_ack_end(substream);
1585 kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1588 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1590 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1591 unsigned int hwoff,
1592 unsigned long data, unsigned int off,
1593 snd_pcm_uframes_t frames)
1595 struct snd_pcm_runtime *runtime = substream->runtime;
1596 int err;
1597 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1598 if (substream->ops->copy) {
1599 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1600 return err;
1601 } else {
1602 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1603 snd_assert(runtime->dma_area, return -EFAULT);
1604 if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1605 return -EFAULT;
1607 return 0;
1610 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1611 unsigned long data, unsigned int off,
1612 snd_pcm_uframes_t size);
1614 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1615 unsigned long data,
1616 snd_pcm_uframes_t size,
1617 int nonblock,
1618 transfer_f transfer)
1620 struct snd_pcm_runtime *runtime = substream->runtime;
1621 snd_pcm_uframes_t xfer = 0;
1622 snd_pcm_uframes_t offset = 0;
1623 int err = 0;
1625 if (size == 0)
1626 return 0;
1627 if (size > runtime->xfer_align)
1628 size -= size % runtime->xfer_align;
1630 snd_pcm_stream_lock_irq(substream);
1631 switch (runtime->status->state) {
1632 case SNDRV_PCM_STATE_PREPARED:
1633 case SNDRV_PCM_STATE_RUNNING:
1634 case SNDRV_PCM_STATE_PAUSED:
1635 break;
1636 case SNDRV_PCM_STATE_XRUN:
1637 err = -EPIPE;
1638 goto _end_unlock;
1639 case SNDRV_PCM_STATE_SUSPENDED:
1640 err = -ESTRPIPE;
1641 goto _end_unlock;
1642 default:
1643 err = -EBADFD;
1644 goto _end_unlock;
1647 while (size > 0) {
1648 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1649 snd_pcm_uframes_t avail;
1650 snd_pcm_uframes_t cont;
1651 if (runtime->sleep_min == 0 && runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1652 snd_pcm_update_hw_ptr(substream);
1653 avail = snd_pcm_playback_avail(runtime);
1654 if (((avail < runtime->control->avail_min && size > avail) ||
1655 (size >= runtime->xfer_align && avail < runtime->xfer_align))) {
1656 wait_queue_t wait;
1657 enum { READY, SIGNALED, ERROR, SUSPENDED, EXPIRED, DROPPED } state;
1658 long tout;
1660 if (nonblock) {
1661 err = -EAGAIN;
1662 goto _end_unlock;
1665 init_waitqueue_entry(&wait, current);
1666 add_wait_queue(&runtime->sleep, &wait);
1667 while (1) {
1668 if (signal_pending(current)) {
1669 state = SIGNALED;
1670 break;
1672 set_current_state(TASK_INTERRUPTIBLE);
1673 snd_pcm_stream_unlock_irq(substream);
1674 tout = schedule_timeout(10 * HZ);
1675 snd_pcm_stream_lock_irq(substream);
1676 if (tout == 0) {
1677 if (runtime->status->state != SNDRV_PCM_STATE_PREPARED &&
1678 runtime->status->state != SNDRV_PCM_STATE_PAUSED) {
1679 state = runtime->status->state == SNDRV_PCM_STATE_SUSPENDED ? SUSPENDED : EXPIRED;
1680 break;
1683 switch (runtime->status->state) {
1684 case SNDRV_PCM_STATE_XRUN:
1685 case SNDRV_PCM_STATE_DRAINING:
1686 state = ERROR;
1687 goto _end_loop;
1688 case SNDRV_PCM_STATE_SUSPENDED:
1689 state = SUSPENDED;
1690 goto _end_loop;
1691 case SNDRV_PCM_STATE_SETUP:
1692 state = DROPPED;
1693 goto _end_loop;
1694 default:
1695 break;
1697 avail = snd_pcm_playback_avail(runtime);
1698 if (avail >= runtime->control->avail_min) {
1699 state = READY;
1700 break;
1703 _end_loop:
1704 remove_wait_queue(&runtime->sleep, &wait);
1706 switch (state) {
1707 case ERROR:
1708 err = -EPIPE;
1709 goto _end_unlock;
1710 case SUSPENDED:
1711 err = -ESTRPIPE;
1712 goto _end_unlock;
1713 case SIGNALED:
1714 err = -ERESTARTSYS;
1715 goto _end_unlock;
1716 case EXPIRED:
1717 snd_printd("playback write error (DMA or IRQ trouble?)\n");
1718 err = -EIO;
1719 goto _end_unlock;
1720 case DROPPED:
1721 err = -EBADFD;
1722 goto _end_unlock;
1723 default:
1724 break;
1727 if (avail > runtime->xfer_align)
1728 avail -= avail % runtime->xfer_align;
1729 frames = size > avail ? avail : size;
1730 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1731 if (frames > cont)
1732 frames = cont;
1733 snd_assert(frames != 0, snd_pcm_stream_unlock_irq(substream); return -EINVAL);
1734 appl_ptr = runtime->control->appl_ptr;
1735 appl_ofs = appl_ptr % runtime->buffer_size;
1736 snd_pcm_stream_unlock_irq(substream);
1737 if ((err = transfer(substream, appl_ofs, data, offset, frames)) < 0)
1738 goto _end;
1739 snd_pcm_stream_lock_irq(substream);
1740 switch (runtime->status->state) {
1741 case SNDRV_PCM_STATE_XRUN:
1742 err = -EPIPE;
1743 goto _end_unlock;
1744 case SNDRV_PCM_STATE_SUSPENDED:
1745 err = -ESTRPIPE;
1746 goto _end_unlock;
1747 default:
1748 break;
1750 appl_ptr += frames;
1751 if (appl_ptr >= runtime->boundary)
1752 appl_ptr -= runtime->boundary;
1753 runtime->control->appl_ptr = appl_ptr;
1754 if (substream->ops->ack)
1755 substream->ops->ack(substream);
1757 offset += frames;
1758 size -= frames;
1759 xfer += frames;
1760 if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1761 snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1762 err = snd_pcm_start(substream);
1763 if (err < 0)
1764 goto _end_unlock;
1766 if (runtime->sleep_min &&
1767 runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1768 snd_pcm_tick_prepare(substream);
1770 _end_unlock:
1771 snd_pcm_stream_unlock_irq(substream);
1772 _end:
1773 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
1776 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
1778 struct snd_pcm_runtime *runtime;
1779 int nonblock;
1781 snd_assert(substream != NULL, return -ENXIO);
1782 runtime = substream->runtime;
1783 snd_assert(runtime != NULL, return -ENXIO);
1784 snd_assert(substream->ops->copy != NULL || runtime->dma_area != NULL, return -EINVAL);
1785 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1786 return -EBADFD;
1788 nonblock = !!(substream->f_flags & O_NONBLOCK);
1790 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
1791 runtime->channels > 1)
1792 return -EINVAL;
1793 return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
1794 snd_pcm_lib_write_transfer);
1797 EXPORT_SYMBOL(snd_pcm_lib_write);
1799 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
1800 unsigned int hwoff,
1801 unsigned long data, unsigned int off,
1802 snd_pcm_uframes_t frames)
1804 struct snd_pcm_runtime *runtime = substream->runtime;
1805 int err;
1806 void __user **bufs = (void __user **)data;
1807 int channels = runtime->channels;
1808 int c;
1809 if (substream->ops->copy) {
1810 snd_assert(substream->ops->silence != NULL, return -EINVAL);
1811 for (c = 0; c < channels; ++c, ++bufs) {
1812 if (*bufs == NULL) {
1813 if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
1814 return err;
1815 } else {
1816 char __user *buf = *bufs + samples_to_bytes(runtime, off);
1817 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
1818 return err;
1821 } else {
1822 /* default transfer behaviour */
1823 size_t dma_csize = runtime->dma_bytes / channels;
1824 snd_assert(runtime->dma_area, return -EFAULT);
1825 for (c = 0; c < channels; ++c, ++bufs) {
1826 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
1827 if (*bufs == NULL) {
1828 snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
1829 } else {
1830 char __user *buf = *bufs + samples_to_bytes(runtime, off);
1831 if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
1832 return -EFAULT;
1836 return 0;
1839 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
1840 void __user **bufs,
1841 snd_pcm_uframes_t frames)
1843 struct snd_pcm_runtime *runtime;
1844 int nonblock;
1846 snd_assert(substream != NULL, return -ENXIO);
1847 runtime = substream->runtime;
1848 snd_assert(runtime != NULL, return -ENXIO);
1849 snd_assert(substream->ops->copy != NULL || runtime->dma_area != NULL, return -EINVAL);
1850 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1851 return -EBADFD;
1853 nonblock = !!(substream->f_flags & O_NONBLOCK);
1855 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
1856 return -EINVAL;
1857 return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
1858 nonblock, snd_pcm_lib_writev_transfer);
1861 EXPORT_SYMBOL(snd_pcm_lib_writev);
1863 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
1864 unsigned int hwoff,
1865 unsigned long data, unsigned int off,
1866 snd_pcm_uframes_t frames)
1868 struct snd_pcm_runtime *runtime = substream->runtime;
1869 int err;
1870 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1871 if (substream->ops->copy) {
1872 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1873 return err;
1874 } else {
1875 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1876 snd_assert(runtime->dma_area, return -EFAULT);
1877 if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
1878 return -EFAULT;
1880 return 0;
1883 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
1884 unsigned long data,
1885 snd_pcm_uframes_t size,
1886 int nonblock,
1887 transfer_f transfer)
1889 struct snd_pcm_runtime *runtime = substream->runtime;
1890 snd_pcm_uframes_t xfer = 0;
1891 snd_pcm_uframes_t offset = 0;
1892 int err = 0;
1894 if (size == 0)
1895 return 0;
1896 if (size > runtime->xfer_align)
1897 size -= size % runtime->xfer_align;
1899 snd_pcm_stream_lock_irq(substream);
1900 switch (runtime->status->state) {
1901 case SNDRV_PCM_STATE_PREPARED:
1902 if (size >= runtime->start_threshold) {
1903 err = snd_pcm_start(substream);
1904 if (err < 0)
1905 goto _end_unlock;
1907 break;
1908 case SNDRV_PCM_STATE_DRAINING:
1909 case SNDRV_PCM_STATE_RUNNING:
1910 case SNDRV_PCM_STATE_PAUSED:
1911 break;
1912 case SNDRV_PCM_STATE_XRUN:
1913 err = -EPIPE;
1914 goto _end_unlock;
1915 case SNDRV_PCM_STATE_SUSPENDED:
1916 err = -ESTRPIPE;
1917 goto _end_unlock;
1918 default:
1919 err = -EBADFD;
1920 goto _end_unlock;
1923 while (size > 0) {
1924 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1925 snd_pcm_uframes_t avail;
1926 snd_pcm_uframes_t cont;
1927 if (runtime->sleep_min == 0 && runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1928 snd_pcm_update_hw_ptr(substream);
1929 __draining:
1930 avail = snd_pcm_capture_avail(runtime);
1931 if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
1932 if (avail < runtime->xfer_align) {
1933 err = -EPIPE;
1934 goto _end_unlock;
1936 } else if ((avail < runtime->control->avail_min && size > avail) ||
1937 (size >= runtime->xfer_align && avail < runtime->xfer_align)) {
1938 wait_queue_t wait;
1939 enum { READY, SIGNALED, ERROR, SUSPENDED, EXPIRED, DROPPED } state;
1940 long tout;
1942 if (nonblock) {
1943 err = -EAGAIN;
1944 goto _end_unlock;
1947 init_waitqueue_entry(&wait, current);
1948 add_wait_queue(&runtime->sleep, &wait);
1949 while (1) {
1950 if (signal_pending(current)) {
1951 state = SIGNALED;
1952 break;
1954 set_current_state(TASK_INTERRUPTIBLE);
1955 snd_pcm_stream_unlock_irq(substream);
1956 tout = schedule_timeout(10 * HZ);
1957 snd_pcm_stream_lock_irq(substream);
1958 if (tout == 0) {
1959 if (runtime->status->state != SNDRV_PCM_STATE_PREPARED &&
1960 runtime->status->state != SNDRV_PCM_STATE_PAUSED) {
1961 state = runtime->status->state == SNDRV_PCM_STATE_SUSPENDED ? SUSPENDED : EXPIRED;
1962 break;
1965 switch (runtime->status->state) {
1966 case SNDRV_PCM_STATE_XRUN:
1967 state = ERROR;
1968 goto _end_loop;
1969 case SNDRV_PCM_STATE_SUSPENDED:
1970 state = SUSPENDED;
1971 goto _end_loop;
1972 case SNDRV_PCM_STATE_DRAINING:
1973 goto __draining;
1974 case SNDRV_PCM_STATE_SETUP:
1975 state = DROPPED;
1976 goto _end_loop;
1977 default:
1978 break;
1980 avail = snd_pcm_capture_avail(runtime);
1981 if (avail >= runtime->control->avail_min) {
1982 state = READY;
1983 break;
1986 _end_loop:
1987 remove_wait_queue(&runtime->sleep, &wait);
1989 switch (state) {
1990 case ERROR:
1991 err = -EPIPE;
1992 goto _end_unlock;
1993 case SUSPENDED:
1994 err = -ESTRPIPE;
1995 goto _end_unlock;
1996 case SIGNALED:
1997 err = -ERESTARTSYS;
1998 goto _end_unlock;
1999 case EXPIRED:
2000 snd_printd("capture read error (DMA or IRQ trouble?)\n");
2001 err = -EIO;
2002 goto _end_unlock;
2003 case DROPPED:
2004 err = -EBADFD;
2005 goto _end_unlock;
2006 default:
2007 break;
2010 if (avail > runtime->xfer_align)
2011 avail -= avail % runtime->xfer_align;
2012 frames = size > avail ? avail : size;
2013 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2014 if (frames > cont)
2015 frames = cont;
2016 snd_assert(frames != 0, snd_pcm_stream_unlock_irq(substream); return -EINVAL);
2017 appl_ptr = runtime->control->appl_ptr;
2018 appl_ofs = appl_ptr % runtime->buffer_size;
2019 snd_pcm_stream_unlock_irq(substream);
2020 if ((err = transfer(substream, appl_ofs, data, offset, frames)) < 0)
2021 goto _end;
2022 snd_pcm_stream_lock_irq(substream);
2023 switch (runtime->status->state) {
2024 case SNDRV_PCM_STATE_XRUN:
2025 err = -EPIPE;
2026 goto _end_unlock;
2027 case SNDRV_PCM_STATE_SUSPENDED:
2028 err = -ESTRPIPE;
2029 goto _end_unlock;
2030 default:
2031 break;
2033 appl_ptr += frames;
2034 if (appl_ptr >= runtime->boundary)
2035 appl_ptr -= runtime->boundary;
2036 runtime->control->appl_ptr = appl_ptr;
2037 if (substream->ops->ack)
2038 substream->ops->ack(substream);
2040 offset += frames;
2041 size -= frames;
2042 xfer += frames;
2043 if (runtime->sleep_min &&
2044 runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2045 snd_pcm_tick_prepare(substream);
2047 _end_unlock:
2048 snd_pcm_stream_unlock_irq(substream);
2049 _end:
2050 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2053 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2055 struct snd_pcm_runtime *runtime;
2056 int nonblock;
2058 snd_assert(substream != NULL, return -ENXIO);
2059 runtime = substream->runtime;
2060 snd_assert(runtime != NULL, return -ENXIO);
2061 snd_assert(substream->ops->copy != NULL || runtime->dma_area != NULL, return -EINVAL);
2062 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2063 return -EBADFD;
2065 nonblock = !!(substream->f_flags & O_NONBLOCK);
2066 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2067 return -EINVAL;
2068 return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2071 EXPORT_SYMBOL(snd_pcm_lib_read);
2073 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2074 unsigned int hwoff,
2075 unsigned long data, unsigned int off,
2076 snd_pcm_uframes_t frames)
2078 struct snd_pcm_runtime *runtime = substream->runtime;
2079 int err;
2080 void __user **bufs = (void __user **)data;
2081 int channels = runtime->channels;
2082 int c;
2083 if (substream->ops->copy) {
2084 for (c = 0; c < channels; ++c, ++bufs) {
2085 char __user *buf;
2086 if (*bufs == NULL)
2087 continue;
2088 buf = *bufs + samples_to_bytes(runtime, off);
2089 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2090 return err;
2092 } else {
2093 snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2094 snd_assert(runtime->dma_area, return -EFAULT);
2095 for (c = 0; c < channels; ++c, ++bufs) {
2096 char *hwbuf;
2097 char __user *buf;
2098 if (*bufs == NULL)
2099 continue;
2101 hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2102 buf = *bufs + samples_to_bytes(runtime, off);
2103 if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2104 return -EFAULT;
2107 return 0;
2110 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2111 void __user **bufs,
2112 snd_pcm_uframes_t frames)
2114 struct snd_pcm_runtime *runtime;
2115 int nonblock;
2117 snd_assert(substream != NULL, return -ENXIO);
2118 runtime = substream->runtime;
2119 snd_assert(runtime != NULL, return -ENXIO);
2120 snd_assert(substream->ops->copy != NULL || runtime->dma_area != NULL, return -EINVAL);
2121 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2122 return -EBADFD;
2124 nonblock = !!(substream->f_flags & O_NONBLOCK);
2125 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2126 return -EINVAL;
2127 return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2130 EXPORT_SYMBOL(snd_pcm_lib_readv);