dm snapshot: only take lock for statustype info not table
[linux-2.6/x86.git] / sound / core / pcm_lib.c
blob30f410832a25991c44e2f71efcebb63abdb2b232
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 <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;
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 if (snd_BUG_ON(frames > runtime->buffer_size))
90 return;
91 if (frames == 0)
92 return;
93 ofs = runtime->silence_start % runtime->buffer_size;
94 while (frames > 0) {
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) {
99 int err;
100 err = substream->ops->silence(substream, -1, ofs, transfer);
101 snd_BUG_ON(err < 0);
102 } else {
103 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
104 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
106 } else {
107 unsigned int c;
108 unsigned int channels = runtime->channels;
109 if (substream->ops->silence) {
110 for (c = 0; c < channels; ++c) {
111 int err;
112 err = substream->ops->silence(substream, c, ofs, transfer);
113 snd_BUG_ON(err < 0);
115 } else {
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;
124 frames -= transfer;
125 ofs = 0;
129 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
130 #define xrun_debug(substream, mask) ((substream)->pstr->xrun_debug & (mask))
131 #else
132 #define xrun_debug(substream, mask) 0
133 #endif
135 #define dump_stack_on_xrun(substream) do { \
136 if (xrun_debug(substream, 2)) \
137 dump_stack(); \
138 } while (0)
140 static void pcm_debug_name(struct snd_pcm_substream *substream,
141 char *name, size_t len)
143 snprintf(name, len, "pcmC%dD%d%c:%d",
144 substream->pcm->card->number,
145 substream->pcm->device,
146 substream->stream ? 'c' : 'p',
147 substream->number);
150 static void xrun(struct snd_pcm_substream *substream)
152 struct snd_pcm_runtime *runtime = substream->runtime;
154 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
155 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
156 snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
157 if (xrun_debug(substream, 1)) {
158 char name[16];
159 pcm_debug_name(substream, name, sizeof(name));
160 snd_printd(KERN_DEBUG "XRUN: %s\n", name);
161 dump_stack_on_xrun(substream);
165 static snd_pcm_uframes_t
166 snd_pcm_update_hw_ptr_pos(struct snd_pcm_substream *substream,
167 struct snd_pcm_runtime *runtime)
169 snd_pcm_uframes_t pos;
171 pos = substream->ops->pointer(substream);
172 if (pos == SNDRV_PCM_POS_XRUN)
173 return pos; /* XRUN */
174 if (pos >= runtime->buffer_size) {
175 if (printk_ratelimit()) {
176 char name[16];
177 pcm_debug_name(substream, name, sizeof(name));
178 snd_printd(KERN_ERR "BUG: %s, pos = 0x%lx, "
179 "buffer size = 0x%lx, period size = 0x%lx\n",
180 name, pos, runtime->buffer_size,
181 runtime->period_size);
183 pos = 0;
185 pos -= pos % runtime->min_align;
186 return pos;
189 static int snd_pcm_update_hw_ptr_post(struct snd_pcm_substream *substream,
190 struct snd_pcm_runtime *runtime)
192 snd_pcm_uframes_t avail;
194 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
195 avail = snd_pcm_playback_avail(runtime);
196 else
197 avail = snd_pcm_capture_avail(runtime);
198 if (avail > runtime->avail_max)
199 runtime->avail_max = avail;
200 if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
201 if (avail >= runtime->buffer_size) {
202 snd_pcm_drain_done(substream);
203 return -EPIPE;
205 } else {
206 if (avail >= runtime->stop_threshold) {
207 xrun(substream);
208 return -EPIPE;
211 if (avail >= runtime->control->avail_min)
212 wake_up(&runtime->sleep);
213 return 0;
216 #define hw_ptr_error(substream, fmt, args...) \
217 do { \
218 if (xrun_debug(substream, 1)) { \
219 if (printk_ratelimit()) { \
220 snd_printd("PCM: " fmt, ##args); \
222 dump_stack_on_xrun(substream); \
224 } while (0)
226 static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream)
228 struct snd_pcm_runtime *runtime = substream->runtime;
229 snd_pcm_uframes_t pos;
230 snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_ptr_interrupt, hw_base;
231 snd_pcm_sframes_t hdelta, delta;
232 unsigned long jdelta;
234 old_hw_ptr = runtime->status->hw_ptr;
235 pos = snd_pcm_update_hw_ptr_pos(substream, runtime);
236 if (pos == SNDRV_PCM_POS_XRUN) {
237 xrun(substream);
238 return -EPIPE;
240 if (xrun_debug(substream, 8)) {
241 char name[16];
242 pcm_debug_name(substream, name, sizeof(name));
243 snd_printd("period_update: %s: pos=0x%x/0x%x/0x%x, "
244 "hwptr=0x%lx, hw_base=0x%lx, hw_intr=0x%lx\n",
245 name, (unsigned int)pos,
246 (unsigned int)runtime->period_size,
247 (unsigned int)runtime->buffer_size,
248 (unsigned long)old_hw_ptr,
249 (unsigned long)runtime->hw_ptr_base,
250 (unsigned long)runtime->hw_ptr_interrupt);
252 hw_base = runtime->hw_ptr_base;
253 new_hw_ptr = hw_base + pos;
254 hw_ptr_interrupt = runtime->hw_ptr_interrupt + runtime->period_size;
255 delta = new_hw_ptr - hw_ptr_interrupt;
256 if (hw_ptr_interrupt >= runtime->boundary) {
257 hw_ptr_interrupt -= runtime->boundary;
258 if (hw_base < runtime->boundary / 2)
259 /* hw_base was already lapped; recalc delta */
260 delta = new_hw_ptr - hw_ptr_interrupt;
262 if (delta < 0) {
263 if (runtime->periods == 1 || new_hw_ptr < old_hw_ptr)
264 delta += runtime->buffer_size;
265 if (delta < 0) {
266 hw_ptr_error(substream,
267 "Unexpected hw_pointer value "
268 "(stream=%i, pos=%ld, intr_ptr=%ld)\n",
269 substream->stream, (long)pos,
270 (long)hw_ptr_interrupt);
271 #if 1
272 /* simply skipping the hwptr update seems more
273 * robust in some cases, e.g. on VMware with
274 * inaccurate timer source
276 return 0; /* skip this update */
277 #else
278 /* rebase to interrupt position */
279 hw_base = new_hw_ptr = hw_ptr_interrupt;
280 /* align hw_base to buffer_size */
281 hw_base -= hw_base % runtime->buffer_size;
282 delta = 0;
283 #endif
284 } else {
285 hw_base += runtime->buffer_size;
286 if (hw_base >= runtime->boundary)
287 hw_base = 0;
288 new_hw_ptr = hw_base + pos;
292 /* Do jiffies check only in xrun_debug mode */
293 if (!xrun_debug(substream, 4))
294 goto no_jiffies_check;
296 /* Skip the jiffies check for hardwares with BATCH flag.
297 * Such hardware usually just increases the position at each IRQ,
298 * thus it can't give any strange position.
300 if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
301 goto no_jiffies_check;
302 hdelta = new_hw_ptr - old_hw_ptr;
303 if (hdelta < runtime->delay)
304 goto no_jiffies_check;
305 hdelta -= runtime->delay;
306 jdelta = jiffies - runtime->hw_ptr_jiffies;
307 if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
308 delta = jdelta /
309 (((runtime->period_size * HZ) / runtime->rate)
310 + HZ/100);
311 hw_ptr_error(substream,
312 "hw_ptr skipping! [Q] "
313 "(pos=%ld, delta=%ld, period=%ld, "
314 "jdelta=%lu/%lu/%lu)\n",
315 (long)pos, (long)hdelta,
316 (long)runtime->period_size, jdelta,
317 ((hdelta * HZ) / runtime->rate), delta);
318 hw_ptr_interrupt = runtime->hw_ptr_interrupt +
319 runtime->period_size * delta;
320 if (hw_ptr_interrupt >= runtime->boundary)
321 hw_ptr_interrupt -= runtime->boundary;
322 /* rebase to interrupt position */
323 hw_base = new_hw_ptr = hw_ptr_interrupt;
324 /* align hw_base to buffer_size */
325 hw_base -= hw_base % runtime->buffer_size;
326 delta = 0;
328 no_jiffies_check:
329 if (delta > runtime->period_size + runtime->period_size / 2) {
330 hw_ptr_error(substream,
331 "Lost interrupts? "
332 "(stream=%i, delta=%ld, intr_ptr=%ld)\n",
333 substream->stream, (long)delta,
334 (long)hw_ptr_interrupt);
335 /* rebase hw_ptr_interrupt */
336 hw_ptr_interrupt =
337 new_hw_ptr - new_hw_ptr % runtime->period_size;
339 runtime->hw_ptr_interrupt = hw_ptr_interrupt;
341 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
342 runtime->silence_size > 0)
343 snd_pcm_playback_silence(substream, new_hw_ptr);
345 if (runtime->status->hw_ptr == new_hw_ptr)
346 return 0;
348 runtime->hw_ptr_base = hw_base;
349 runtime->status->hw_ptr = new_hw_ptr;
350 runtime->hw_ptr_jiffies = jiffies;
351 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
352 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
354 return snd_pcm_update_hw_ptr_post(substream, runtime);
357 /* CAUTION: call it with irq disabled */
358 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
360 struct snd_pcm_runtime *runtime = substream->runtime;
361 snd_pcm_uframes_t pos;
362 snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
363 snd_pcm_sframes_t delta;
364 unsigned long jdelta;
366 old_hw_ptr = runtime->status->hw_ptr;
367 pos = snd_pcm_update_hw_ptr_pos(substream, runtime);
368 if (pos == SNDRV_PCM_POS_XRUN) {
369 xrun(substream);
370 return -EPIPE;
372 if (xrun_debug(substream, 16)) {
373 char name[16];
374 pcm_debug_name(substream, name, sizeof(name));
375 snd_printd("hw_update: %s: pos=0x%x/0x%x/0x%x, "
376 "hwptr=0x%lx, hw_base=0x%lx, hw_intr=0x%lx\n",
377 name, (unsigned int)pos,
378 (unsigned int)runtime->period_size,
379 (unsigned int)runtime->buffer_size,
380 (unsigned long)old_hw_ptr,
381 (unsigned long)runtime->hw_ptr_base,
382 (unsigned long)runtime->hw_ptr_interrupt);
385 hw_base = runtime->hw_ptr_base;
386 new_hw_ptr = hw_base + pos;
388 delta = new_hw_ptr - old_hw_ptr;
389 jdelta = jiffies - runtime->hw_ptr_jiffies;
390 if (delta < 0) {
391 delta += runtime->buffer_size;
392 if (delta < 0) {
393 hw_ptr_error(substream,
394 "Unexpected hw_pointer value [2] "
395 "(stream=%i, pos=%ld, old_ptr=%ld, jdelta=%li)\n",
396 substream->stream, (long)pos,
397 (long)old_hw_ptr, jdelta);
398 return 0;
400 hw_base += runtime->buffer_size;
401 if (hw_base >= runtime->boundary)
402 hw_base = 0;
403 new_hw_ptr = hw_base + pos;
405 /* Do jiffies check only in xrun_debug mode */
406 if (!xrun_debug(substream, 4))
407 goto no_jiffies_check;
408 if (delta < runtime->delay)
409 goto no_jiffies_check;
410 delta -= runtime->delay;
411 if (((delta * HZ) / runtime->rate) > jdelta + HZ/100) {
412 hw_ptr_error(substream,
413 "hw_ptr skipping! "
414 "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu)\n",
415 (long)pos, (long)delta,
416 (long)runtime->period_size, jdelta,
417 ((delta * HZ) / runtime->rate));
418 return 0;
420 no_jiffies_check:
421 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
422 runtime->silence_size > 0)
423 snd_pcm_playback_silence(substream, new_hw_ptr);
425 if (runtime->status->hw_ptr == new_hw_ptr)
426 return 0;
428 runtime->hw_ptr_base = hw_base;
429 runtime->status->hw_ptr = new_hw_ptr;
430 runtime->hw_ptr_jiffies = jiffies;
431 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
432 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
434 return snd_pcm_update_hw_ptr_post(substream, runtime);
438 * snd_pcm_set_ops - set the PCM operators
439 * @pcm: the pcm instance
440 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
441 * @ops: the operator table
443 * Sets the given PCM operators to the pcm instance.
445 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction, struct snd_pcm_ops *ops)
447 struct snd_pcm_str *stream = &pcm->streams[direction];
448 struct snd_pcm_substream *substream;
450 for (substream = stream->substream; substream != NULL; substream = substream->next)
451 substream->ops = ops;
454 EXPORT_SYMBOL(snd_pcm_set_ops);
457 * snd_pcm_sync - set the PCM sync id
458 * @substream: the pcm substream
460 * Sets the PCM sync identifier for the card.
462 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
464 struct snd_pcm_runtime *runtime = substream->runtime;
466 runtime->sync.id32[0] = substream->pcm->card->number;
467 runtime->sync.id32[1] = -1;
468 runtime->sync.id32[2] = -1;
469 runtime->sync.id32[3] = -1;
472 EXPORT_SYMBOL(snd_pcm_set_sync);
475 * Standard ioctl routine
478 static inline unsigned int div32(unsigned int a, unsigned int b,
479 unsigned int *r)
481 if (b == 0) {
482 *r = 0;
483 return UINT_MAX;
485 *r = a % b;
486 return a / b;
489 static inline unsigned int div_down(unsigned int a, unsigned int b)
491 if (b == 0)
492 return UINT_MAX;
493 return a / b;
496 static inline unsigned int div_up(unsigned int a, unsigned int b)
498 unsigned int r;
499 unsigned int q;
500 if (b == 0)
501 return UINT_MAX;
502 q = div32(a, b, &r);
503 if (r)
504 ++q;
505 return q;
508 static inline unsigned int mul(unsigned int a, unsigned int b)
510 if (a == 0)
511 return 0;
512 if (div_down(UINT_MAX, a) < b)
513 return UINT_MAX;
514 return a * b;
517 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
518 unsigned int c, unsigned int *r)
520 u_int64_t n = (u_int64_t) a * b;
521 if (c == 0) {
522 snd_BUG_ON(!n);
523 *r = 0;
524 return UINT_MAX;
526 n = div_u64_rem(n, c, r);
527 if (n >= UINT_MAX) {
528 *r = 0;
529 return UINT_MAX;
531 return n;
535 * snd_interval_refine - refine the interval value of configurator
536 * @i: the interval value to refine
537 * @v: the interval value to refer to
539 * Refines the interval value with the reference value.
540 * The interval is changed to the range satisfying both intervals.
541 * The interval status (min, max, integer, etc.) are evaluated.
543 * Returns non-zero if the value is changed, zero if not changed.
545 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
547 int changed = 0;
548 if (snd_BUG_ON(snd_interval_empty(i)))
549 return -EINVAL;
550 if (i->min < v->min) {
551 i->min = v->min;
552 i->openmin = v->openmin;
553 changed = 1;
554 } else if (i->min == v->min && !i->openmin && v->openmin) {
555 i->openmin = 1;
556 changed = 1;
558 if (i->max > v->max) {
559 i->max = v->max;
560 i->openmax = v->openmax;
561 changed = 1;
562 } else if (i->max == v->max && !i->openmax && v->openmax) {
563 i->openmax = 1;
564 changed = 1;
566 if (!i->integer && v->integer) {
567 i->integer = 1;
568 changed = 1;
570 if (i->integer) {
571 if (i->openmin) {
572 i->min++;
573 i->openmin = 0;
575 if (i->openmax) {
576 i->max--;
577 i->openmax = 0;
579 } else if (!i->openmin && !i->openmax && i->min == i->max)
580 i->integer = 1;
581 if (snd_interval_checkempty(i)) {
582 snd_interval_none(i);
583 return -EINVAL;
585 return changed;
588 EXPORT_SYMBOL(snd_interval_refine);
590 static int snd_interval_refine_first(struct snd_interval *i)
592 if (snd_BUG_ON(snd_interval_empty(i)))
593 return -EINVAL;
594 if (snd_interval_single(i))
595 return 0;
596 i->max = i->min;
597 i->openmax = i->openmin;
598 if (i->openmax)
599 i->max++;
600 return 1;
603 static int snd_interval_refine_last(struct snd_interval *i)
605 if (snd_BUG_ON(snd_interval_empty(i)))
606 return -EINVAL;
607 if (snd_interval_single(i))
608 return 0;
609 i->min = i->max;
610 i->openmin = i->openmax;
611 if (i->openmin)
612 i->min--;
613 return 1;
616 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
618 if (a->empty || b->empty) {
619 snd_interval_none(c);
620 return;
622 c->empty = 0;
623 c->min = mul(a->min, b->min);
624 c->openmin = (a->openmin || b->openmin);
625 c->max = mul(a->max, b->max);
626 c->openmax = (a->openmax || b->openmax);
627 c->integer = (a->integer && b->integer);
631 * snd_interval_div - refine the interval value with division
632 * @a: dividend
633 * @b: divisor
634 * @c: quotient
636 * c = a / b
638 * Returns non-zero if the value is changed, zero if not changed.
640 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
642 unsigned int r;
643 if (a->empty || b->empty) {
644 snd_interval_none(c);
645 return;
647 c->empty = 0;
648 c->min = div32(a->min, b->max, &r);
649 c->openmin = (r || a->openmin || b->openmax);
650 if (b->min > 0) {
651 c->max = div32(a->max, b->min, &r);
652 if (r) {
653 c->max++;
654 c->openmax = 1;
655 } else
656 c->openmax = (a->openmax || b->openmin);
657 } else {
658 c->max = UINT_MAX;
659 c->openmax = 0;
661 c->integer = 0;
665 * snd_interval_muldivk - refine the interval value
666 * @a: dividend 1
667 * @b: dividend 2
668 * @k: divisor (as integer)
669 * @c: result
671 * c = a * b / k
673 * Returns non-zero if the value is changed, zero if not changed.
675 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
676 unsigned int k, struct snd_interval *c)
678 unsigned int r;
679 if (a->empty || b->empty) {
680 snd_interval_none(c);
681 return;
683 c->empty = 0;
684 c->min = muldiv32(a->min, b->min, k, &r);
685 c->openmin = (r || a->openmin || b->openmin);
686 c->max = muldiv32(a->max, b->max, k, &r);
687 if (r) {
688 c->max++;
689 c->openmax = 1;
690 } else
691 c->openmax = (a->openmax || b->openmax);
692 c->integer = 0;
696 * snd_interval_mulkdiv - refine the interval value
697 * @a: dividend 1
698 * @k: dividend 2 (as integer)
699 * @b: divisor
700 * @c: result
702 * c = a * k / b
704 * Returns non-zero if the value is changed, zero if not changed.
706 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
707 const struct snd_interval *b, struct snd_interval *c)
709 unsigned int r;
710 if (a->empty || b->empty) {
711 snd_interval_none(c);
712 return;
714 c->empty = 0;
715 c->min = muldiv32(a->min, k, b->max, &r);
716 c->openmin = (r || a->openmin || b->openmax);
717 if (b->min > 0) {
718 c->max = muldiv32(a->max, k, b->min, &r);
719 if (r) {
720 c->max++;
721 c->openmax = 1;
722 } else
723 c->openmax = (a->openmax || b->openmin);
724 } else {
725 c->max = UINT_MAX;
726 c->openmax = 0;
728 c->integer = 0;
731 /* ---- */
735 * snd_interval_ratnum - refine the interval value
736 * @i: interval to refine
737 * @rats_count: number of ratnum_t
738 * @rats: ratnum_t array
739 * @nump: pointer to store the resultant numerator
740 * @denp: pointer to store the resultant denominator
742 * Returns non-zero if the value is changed, zero if not changed.
744 int snd_interval_ratnum(struct snd_interval *i,
745 unsigned int rats_count, struct snd_ratnum *rats,
746 unsigned int *nump, unsigned int *denp)
748 unsigned int best_num, best_diff, best_den;
749 unsigned int k;
750 struct snd_interval t;
751 int err;
753 best_num = best_den = best_diff = 0;
754 for (k = 0; k < rats_count; ++k) {
755 unsigned int num = rats[k].num;
756 unsigned int den;
757 unsigned int q = i->min;
758 int diff;
759 if (q == 0)
760 q = 1;
761 den = div_down(num, q);
762 if (den < rats[k].den_min)
763 continue;
764 if (den > rats[k].den_max)
765 den = rats[k].den_max;
766 else {
767 unsigned int r;
768 r = (den - rats[k].den_min) % rats[k].den_step;
769 if (r != 0)
770 den -= r;
772 diff = num - q * den;
773 if (best_num == 0 ||
774 diff * best_den < best_diff * den) {
775 best_diff = diff;
776 best_den = den;
777 best_num = num;
780 if (best_den == 0) {
781 i->empty = 1;
782 return -EINVAL;
784 t.min = div_down(best_num, best_den);
785 t.openmin = !!(best_num % best_den);
787 best_num = best_den = best_diff = 0;
788 for (k = 0; k < rats_count; ++k) {
789 unsigned int num = rats[k].num;
790 unsigned int den;
791 unsigned int q = i->max;
792 int diff;
793 if (q == 0) {
794 i->empty = 1;
795 return -EINVAL;
797 den = div_up(num, q);
798 if (den > rats[k].den_max)
799 continue;
800 if (den < rats[k].den_min)
801 den = rats[k].den_min;
802 else {
803 unsigned int r;
804 r = (den - rats[k].den_min) % rats[k].den_step;
805 if (r != 0)
806 den += rats[k].den_step - r;
808 diff = q * den - num;
809 if (best_num == 0 ||
810 diff * best_den < best_diff * den) {
811 best_diff = diff;
812 best_den = den;
813 best_num = num;
816 if (best_den == 0) {
817 i->empty = 1;
818 return -EINVAL;
820 t.max = div_up(best_num, best_den);
821 t.openmax = !!(best_num % best_den);
822 t.integer = 0;
823 err = snd_interval_refine(i, &t);
824 if (err < 0)
825 return err;
827 if (snd_interval_single(i)) {
828 if (nump)
829 *nump = best_num;
830 if (denp)
831 *denp = best_den;
833 return err;
836 EXPORT_SYMBOL(snd_interval_ratnum);
839 * snd_interval_ratden - refine the interval value
840 * @i: interval to refine
841 * @rats_count: number of struct ratden
842 * @rats: struct ratden array
843 * @nump: pointer to store the resultant numerator
844 * @denp: pointer to store the resultant denominator
846 * Returns non-zero if the value is changed, zero if not changed.
848 static int snd_interval_ratden(struct snd_interval *i,
849 unsigned int rats_count, struct snd_ratden *rats,
850 unsigned int *nump, unsigned int *denp)
852 unsigned int best_num, best_diff, best_den;
853 unsigned int k;
854 struct snd_interval t;
855 int err;
857 best_num = best_den = best_diff = 0;
858 for (k = 0; k < rats_count; ++k) {
859 unsigned int num;
860 unsigned int den = rats[k].den;
861 unsigned int q = i->min;
862 int diff;
863 num = mul(q, den);
864 if (num > rats[k].num_max)
865 continue;
866 if (num < rats[k].num_min)
867 num = rats[k].num_max;
868 else {
869 unsigned int r;
870 r = (num - rats[k].num_min) % rats[k].num_step;
871 if (r != 0)
872 num += rats[k].num_step - r;
874 diff = num - q * den;
875 if (best_num == 0 ||
876 diff * best_den < best_diff * den) {
877 best_diff = diff;
878 best_den = den;
879 best_num = num;
882 if (best_den == 0) {
883 i->empty = 1;
884 return -EINVAL;
886 t.min = div_down(best_num, best_den);
887 t.openmin = !!(best_num % best_den);
889 best_num = best_den = best_diff = 0;
890 for (k = 0; k < rats_count; ++k) {
891 unsigned int num;
892 unsigned int den = rats[k].den;
893 unsigned int q = i->max;
894 int diff;
895 num = mul(q, den);
896 if (num < rats[k].num_min)
897 continue;
898 if (num > rats[k].num_max)
899 num = rats[k].num_max;
900 else {
901 unsigned int r;
902 r = (num - rats[k].num_min) % rats[k].num_step;
903 if (r != 0)
904 num -= r;
906 diff = q * den - num;
907 if (best_num == 0 ||
908 diff * best_den < best_diff * den) {
909 best_diff = diff;
910 best_den = den;
911 best_num = num;
914 if (best_den == 0) {
915 i->empty = 1;
916 return -EINVAL;
918 t.max = div_up(best_num, best_den);
919 t.openmax = !!(best_num % best_den);
920 t.integer = 0;
921 err = snd_interval_refine(i, &t);
922 if (err < 0)
923 return err;
925 if (snd_interval_single(i)) {
926 if (nump)
927 *nump = best_num;
928 if (denp)
929 *denp = best_den;
931 return err;
935 * snd_interval_list - refine the interval value from the list
936 * @i: the interval value to refine
937 * @count: the number of elements in the list
938 * @list: the value list
939 * @mask: the bit-mask to evaluate
941 * Refines the interval value from the list.
942 * When mask is non-zero, only the elements corresponding to bit 1 are
943 * evaluated.
945 * Returns non-zero if the value is changed, zero if not changed.
947 int snd_interval_list(struct snd_interval *i, unsigned int count, unsigned int *list, unsigned int mask)
949 unsigned int k;
950 struct snd_interval list_range;
952 if (!count) {
953 i->empty = 1;
954 return -EINVAL;
956 snd_interval_any(&list_range);
957 list_range.min = UINT_MAX;
958 list_range.max = 0;
959 for (k = 0; k < count; k++) {
960 if (mask && !(mask & (1 << k)))
961 continue;
962 if (!snd_interval_test(i, list[k]))
963 continue;
964 list_range.min = min(list_range.min, list[k]);
965 list_range.max = max(list_range.max, list[k]);
967 return snd_interval_refine(i, &list_range);
970 EXPORT_SYMBOL(snd_interval_list);
972 static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
974 unsigned int n;
975 int changed = 0;
976 n = (i->min - min) % step;
977 if (n != 0 || i->openmin) {
978 i->min += step - n;
979 changed = 1;
981 n = (i->max - min) % step;
982 if (n != 0 || i->openmax) {
983 i->max -= n;
984 changed = 1;
986 if (snd_interval_checkempty(i)) {
987 i->empty = 1;
988 return -EINVAL;
990 return changed;
993 /* Info constraints helpers */
996 * snd_pcm_hw_rule_add - add the hw-constraint rule
997 * @runtime: the pcm runtime instance
998 * @cond: condition bits
999 * @var: the variable to evaluate
1000 * @func: the evaluation function
1001 * @private: the private data pointer passed to function
1002 * @dep: the dependent variables
1004 * Returns zero if successful, or a negative error code on failure.
1006 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1007 int var,
1008 snd_pcm_hw_rule_func_t func, void *private,
1009 int dep, ...)
1011 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1012 struct snd_pcm_hw_rule *c;
1013 unsigned int k;
1014 va_list args;
1015 va_start(args, dep);
1016 if (constrs->rules_num >= constrs->rules_all) {
1017 struct snd_pcm_hw_rule *new;
1018 unsigned int new_rules = constrs->rules_all + 16;
1019 new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1020 if (!new)
1021 return -ENOMEM;
1022 if (constrs->rules) {
1023 memcpy(new, constrs->rules,
1024 constrs->rules_num * sizeof(*c));
1025 kfree(constrs->rules);
1027 constrs->rules = new;
1028 constrs->rules_all = new_rules;
1030 c = &constrs->rules[constrs->rules_num];
1031 c->cond = cond;
1032 c->func = func;
1033 c->var = var;
1034 c->private = private;
1035 k = 0;
1036 while (1) {
1037 if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps)))
1038 return -EINVAL;
1039 c->deps[k++] = dep;
1040 if (dep < 0)
1041 break;
1042 dep = va_arg(args, int);
1044 constrs->rules_num++;
1045 va_end(args);
1046 return 0;
1049 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1052 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1053 * @runtime: PCM runtime instance
1054 * @var: hw_params variable to apply the mask
1055 * @mask: the bitmap mask
1057 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1059 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1060 u_int32_t mask)
1062 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1063 struct snd_mask *maskp = constrs_mask(constrs, var);
1064 *maskp->bits &= mask;
1065 memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1066 if (*maskp->bits == 0)
1067 return -EINVAL;
1068 return 0;
1072 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1073 * @runtime: PCM runtime instance
1074 * @var: hw_params variable to apply the mask
1075 * @mask: the 64bit bitmap mask
1077 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1079 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1080 u_int64_t mask)
1082 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1083 struct snd_mask *maskp = constrs_mask(constrs, var);
1084 maskp->bits[0] &= (u_int32_t)mask;
1085 maskp->bits[1] &= (u_int32_t)(mask >> 32);
1086 memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1087 if (! maskp->bits[0] && ! maskp->bits[1])
1088 return -EINVAL;
1089 return 0;
1093 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1094 * @runtime: PCM runtime instance
1095 * @var: hw_params variable to apply the integer constraint
1097 * Apply the constraint of integer to an interval parameter.
1099 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1101 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1102 return snd_interval_setinteger(constrs_interval(constrs, var));
1105 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1108 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1109 * @runtime: PCM runtime instance
1110 * @var: hw_params variable to apply the range
1111 * @min: the minimal value
1112 * @max: the maximal value
1114 * Apply the min/max range constraint to an interval parameter.
1116 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1117 unsigned int min, unsigned int max)
1119 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1120 struct snd_interval t;
1121 t.min = min;
1122 t.max = max;
1123 t.openmin = t.openmax = 0;
1124 t.integer = 0;
1125 return snd_interval_refine(constrs_interval(constrs, var), &t);
1128 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1130 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1131 struct snd_pcm_hw_rule *rule)
1133 struct snd_pcm_hw_constraint_list *list = rule->private;
1134 return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1139 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1140 * @runtime: PCM runtime instance
1141 * @cond: condition bits
1142 * @var: hw_params variable to apply the list constraint
1143 * @l: list
1145 * Apply the list of constraints to an interval parameter.
1147 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1148 unsigned int cond,
1149 snd_pcm_hw_param_t var,
1150 struct snd_pcm_hw_constraint_list *l)
1152 return snd_pcm_hw_rule_add(runtime, cond, var,
1153 snd_pcm_hw_rule_list, l,
1154 var, -1);
1157 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1159 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1160 struct snd_pcm_hw_rule *rule)
1162 struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1163 unsigned int num = 0, den = 0;
1164 int err;
1165 err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1166 r->nrats, r->rats, &num, &den);
1167 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1168 params->rate_num = num;
1169 params->rate_den = den;
1171 return err;
1175 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1176 * @runtime: PCM runtime instance
1177 * @cond: condition bits
1178 * @var: hw_params variable to apply the ratnums constraint
1179 * @r: struct snd_ratnums constriants
1181 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1182 unsigned int cond,
1183 snd_pcm_hw_param_t var,
1184 struct snd_pcm_hw_constraint_ratnums *r)
1186 return snd_pcm_hw_rule_add(runtime, cond, var,
1187 snd_pcm_hw_rule_ratnums, r,
1188 var, -1);
1191 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1193 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1194 struct snd_pcm_hw_rule *rule)
1196 struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1197 unsigned int num = 0, den = 0;
1198 int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1199 r->nrats, r->rats, &num, &den);
1200 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1201 params->rate_num = num;
1202 params->rate_den = den;
1204 return err;
1208 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1209 * @runtime: PCM runtime instance
1210 * @cond: condition bits
1211 * @var: hw_params variable to apply the ratdens constraint
1212 * @r: struct snd_ratdens constriants
1214 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1215 unsigned int cond,
1216 snd_pcm_hw_param_t var,
1217 struct snd_pcm_hw_constraint_ratdens *r)
1219 return snd_pcm_hw_rule_add(runtime, cond, var,
1220 snd_pcm_hw_rule_ratdens, r,
1221 var, -1);
1224 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1226 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1227 struct snd_pcm_hw_rule *rule)
1229 unsigned int l = (unsigned long) rule->private;
1230 int width = l & 0xffff;
1231 unsigned int msbits = l >> 16;
1232 struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1233 if (snd_interval_single(i) && snd_interval_value(i) == width)
1234 params->msbits = msbits;
1235 return 0;
1239 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1240 * @runtime: PCM runtime instance
1241 * @cond: condition bits
1242 * @width: sample bits width
1243 * @msbits: msbits width
1245 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1246 unsigned int cond,
1247 unsigned int width,
1248 unsigned int msbits)
1250 unsigned long l = (msbits << 16) | width;
1251 return snd_pcm_hw_rule_add(runtime, cond, -1,
1252 snd_pcm_hw_rule_msbits,
1253 (void*) l,
1254 SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1257 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1259 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1260 struct snd_pcm_hw_rule *rule)
1262 unsigned long step = (unsigned long) rule->private;
1263 return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1267 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1268 * @runtime: PCM runtime instance
1269 * @cond: condition bits
1270 * @var: hw_params variable to apply the step constraint
1271 * @step: step size
1273 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1274 unsigned int cond,
1275 snd_pcm_hw_param_t var,
1276 unsigned long step)
1278 return snd_pcm_hw_rule_add(runtime, cond, var,
1279 snd_pcm_hw_rule_step, (void *) step,
1280 var, -1);
1283 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1285 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1287 static unsigned int pow2_sizes[] = {
1288 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1289 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1290 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1291 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1293 return snd_interval_list(hw_param_interval(params, rule->var),
1294 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1298 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1299 * @runtime: PCM runtime instance
1300 * @cond: condition bits
1301 * @var: hw_params variable to apply the power-of-2 constraint
1303 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1304 unsigned int cond,
1305 snd_pcm_hw_param_t var)
1307 return snd_pcm_hw_rule_add(runtime, cond, var,
1308 snd_pcm_hw_rule_pow2, NULL,
1309 var, -1);
1312 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1314 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1315 snd_pcm_hw_param_t var)
1317 if (hw_is_mask(var)) {
1318 snd_mask_any(hw_param_mask(params, var));
1319 params->cmask |= 1 << var;
1320 params->rmask |= 1 << var;
1321 return;
1323 if (hw_is_interval(var)) {
1324 snd_interval_any(hw_param_interval(params, var));
1325 params->cmask |= 1 << var;
1326 params->rmask |= 1 << var;
1327 return;
1329 snd_BUG();
1332 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1334 unsigned int k;
1335 memset(params, 0, sizeof(*params));
1336 for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1337 _snd_pcm_hw_param_any(params, k);
1338 for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1339 _snd_pcm_hw_param_any(params, k);
1340 params->info = ~0U;
1343 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1346 * snd_pcm_hw_param_value - return @params field @var value
1347 * @params: the hw_params instance
1348 * @var: parameter to retrieve
1349 * @dir: pointer to the direction (-1,0,1) or %NULL
1351 * Return the value for field @var if it's fixed in configuration space
1352 * defined by @params. Return -%EINVAL otherwise.
1354 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1355 snd_pcm_hw_param_t var, int *dir)
1357 if (hw_is_mask(var)) {
1358 const struct snd_mask *mask = hw_param_mask_c(params, var);
1359 if (!snd_mask_single(mask))
1360 return -EINVAL;
1361 if (dir)
1362 *dir = 0;
1363 return snd_mask_value(mask);
1365 if (hw_is_interval(var)) {
1366 const struct snd_interval *i = hw_param_interval_c(params, var);
1367 if (!snd_interval_single(i))
1368 return -EINVAL;
1369 if (dir)
1370 *dir = i->openmin;
1371 return snd_interval_value(i);
1373 return -EINVAL;
1376 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1378 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1379 snd_pcm_hw_param_t var)
1381 if (hw_is_mask(var)) {
1382 snd_mask_none(hw_param_mask(params, var));
1383 params->cmask |= 1 << var;
1384 params->rmask |= 1 << var;
1385 } else if (hw_is_interval(var)) {
1386 snd_interval_none(hw_param_interval(params, var));
1387 params->cmask |= 1 << var;
1388 params->rmask |= 1 << var;
1389 } else {
1390 snd_BUG();
1394 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1396 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1397 snd_pcm_hw_param_t var)
1399 int changed;
1400 if (hw_is_mask(var))
1401 changed = snd_mask_refine_first(hw_param_mask(params, var));
1402 else if (hw_is_interval(var))
1403 changed = snd_interval_refine_first(hw_param_interval(params, var));
1404 else
1405 return -EINVAL;
1406 if (changed) {
1407 params->cmask |= 1 << var;
1408 params->rmask |= 1 << var;
1410 return changed;
1415 * snd_pcm_hw_param_first - refine config space and return minimum value
1416 * @pcm: PCM instance
1417 * @params: the hw_params instance
1418 * @var: parameter to retrieve
1419 * @dir: pointer to the direction (-1,0,1) or %NULL
1421 * Inside configuration space defined by @params remove from @var all
1422 * values > minimum. Reduce configuration space accordingly.
1423 * Return the minimum.
1425 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1426 struct snd_pcm_hw_params *params,
1427 snd_pcm_hw_param_t var, int *dir)
1429 int changed = _snd_pcm_hw_param_first(params, var);
1430 if (changed < 0)
1431 return changed;
1432 if (params->rmask) {
1433 int err = snd_pcm_hw_refine(pcm, params);
1434 if (snd_BUG_ON(err < 0))
1435 return err;
1437 return snd_pcm_hw_param_value(params, var, dir);
1440 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1442 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1443 snd_pcm_hw_param_t var)
1445 int changed;
1446 if (hw_is_mask(var))
1447 changed = snd_mask_refine_last(hw_param_mask(params, var));
1448 else if (hw_is_interval(var))
1449 changed = snd_interval_refine_last(hw_param_interval(params, var));
1450 else
1451 return -EINVAL;
1452 if (changed) {
1453 params->cmask |= 1 << var;
1454 params->rmask |= 1 << var;
1456 return changed;
1461 * snd_pcm_hw_param_last - refine config space and return maximum value
1462 * @pcm: PCM instance
1463 * @params: the hw_params instance
1464 * @var: parameter to retrieve
1465 * @dir: pointer to the direction (-1,0,1) or %NULL
1467 * Inside configuration space defined by @params remove from @var all
1468 * values < maximum. Reduce configuration space accordingly.
1469 * Return the maximum.
1471 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1472 struct snd_pcm_hw_params *params,
1473 snd_pcm_hw_param_t var, int *dir)
1475 int changed = _snd_pcm_hw_param_last(params, var);
1476 if (changed < 0)
1477 return changed;
1478 if (params->rmask) {
1479 int err = snd_pcm_hw_refine(pcm, params);
1480 if (snd_BUG_ON(err < 0))
1481 return err;
1483 return snd_pcm_hw_param_value(params, var, dir);
1486 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1489 * snd_pcm_hw_param_choose - choose a configuration defined by @params
1490 * @pcm: PCM instance
1491 * @params: the hw_params instance
1493 * Choose one configuration from configuration space defined by @params.
1494 * The configuration chosen is that obtained fixing in this order:
1495 * first access, first format, first subformat, min channels,
1496 * min rate, min period time, max buffer size, min tick time
1498 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1499 struct snd_pcm_hw_params *params)
1501 static int vars[] = {
1502 SNDRV_PCM_HW_PARAM_ACCESS,
1503 SNDRV_PCM_HW_PARAM_FORMAT,
1504 SNDRV_PCM_HW_PARAM_SUBFORMAT,
1505 SNDRV_PCM_HW_PARAM_CHANNELS,
1506 SNDRV_PCM_HW_PARAM_RATE,
1507 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1508 SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1509 SNDRV_PCM_HW_PARAM_TICK_TIME,
1512 int err, *v;
1514 for (v = vars; *v != -1; v++) {
1515 if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1516 err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1517 else
1518 err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1519 if (snd_BUG_ON(err < 0))
1520 return err;
1522 return 0;
1525 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1526 void *arg)
1528 struct snd_pcm_runtime *runtime = substream->runtime;
1529 unsigned long flags;
1530 snd_pcm_stream_lock_irqsave(substream, flags);
1531 if (snd_pcm_running(substream) &&
1532 snd_pcm_update_hw_ptr(substream) >= 0)
1533 runtime->status->hw_ptr %= runtime->buffer_size;
1534 else
1535 runtime->status->hw_ptr = 0;
1536 snd_pcm_stream_unlock_irqrestore(substream, flags);
1537 return 0;
1540 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1541 void *arg)
1543 struct snd_pcm_channel_info *info = arg;
1544 struct snd_pcm_runtime *runtime = substream->runtime;
1545 int width;
1546 if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1547 info->offset = -1;
1548 return 0;
1550 width = snd_pcm_format_physical_width(runtime->format);
1551 if (width < 0)
1552 return width;
1553 info->offset = 0;
1554 switch (runtime->access) {
1555 case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1556 case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1557 info->first = info->channel * width;
1558 info->step = runtime->channels * width;
1559 break;
1560 case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1561 case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1563 size_t size = runtime->dma_bytes / runtime->channels;
1564 info->first = info->channel * size * 8;
1565 info->step = width;
1566 break;
1568 default:
1569 snd_BUG();
1570 break;
1572 return 0;
1575 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1576 void *arg)
1578 struct snd_pcm_hw_params *params = arg;
1579 snd_pcm_format_t format;
1580 int channels, width;
1582 params->fifo_size = substream->runtime->hw.fifo_size;
1583 if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1584 format = params_format(params);
1585 channels = params_channels(params);
1586 width = snd_pcm_format_physical_width(format);
1587 params->fifo_size /= width * channels;
1589 return 0;
1593 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1594 * @substream: the pcm substream instance
1595 * @cmd: ioctl command
1596 * @arg: ioctl argument
1598 * Processes the generic ioctl commands for PCM.
1599 * Can be passed as the ioctl callback for PCM ops.
1601 * Returns zero if successful, or a negative error code on failure.
1603 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1604 unsigned int cmd, void *arg)
1606 switch (cmd) {
1607 case SNDRV_PCM_IOCTL1_INFO:
1608 return 0;
1609 case SNDRV_PCM_IOCTL1_RESET:
1610 return snd_pcm_lib_ioctl_reset(substream, arg);
1611 case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1612 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1613 case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1614 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1616 return -ENXIO;
1619 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1622 * snd_pcm_period_elapsed - update the pcm status for the next period
1623 * @substream: the pcm substream instance
1625 * This function is called from the interrupt handler when the
1626 * PCM has processed the period size. It will update the current
1627 * pointer, wake up sleepers, etc.
1629 * Even if more than one periods have elapsed since the last call, you
1630 * have to call this only once.
1632 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1634 struct snd_pcm_runtime *runtime;
1635 unsigned long flags;
1637 if (PCM_RUNTIME_CHECK(substream))
1638 return;
1639 runtime = substream->runtime;
1641 if (runtime->transfer_ack_begin)
1642 runtime->transfer_ack_begin(substream);
1644 snd_pcm_stream_lock_irqsave(substream, flags);
1645 if (!snd_pcm_running(substream) ||
1646 snd_pcm_update_hw_ptr_interrupt(substream) < 0)
1647 goto _end;
1649 if (substream->timer_running)
1650 snd_timer_interrupt(substream->timer, 1);
1651 _end:
1652 snd_pcm_stream_unlock_irqrestore(substream, flags);
1653 if (runtime->transfer_ack_end)
1654 runtime->transfer_ack_end(substream);
1655 kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1658 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1661 * Wait until avail_min data becomes available
1662 * Returns a negative error code if any error occurs during operation.
1663 * The available space is stored on availp. When err = 0 and avail = 0
1664 * on the capture stream, it indicates the stream is in DRAINING state.
1666 static int wait_for_avail_min(struct snd_pcm_substream *substream,
1667 snd_pcm_uframes_t *availp)
1669 struct snd_pcm_runtime *runtime = substream->runtime;
1670 int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1671 wait_queue_t wait;
1672 int err = 0;
1673 snd_pcm_uframes_t avail = 0;
1674 long tout;
1676 init_waitqueue_entry(&wait, current);
1677 add_wait_queue(&runtime->sleep, &wait);
1678 for (;;) {
1679 if (signal_pending(current)) {
1680 err = -ERESTARTSYS;
1681 break;
1683 set_current_state(TASK_INTERRUPTIBLE);
1684 snd_pcm_stream_unlock_irq(substream);
1685 tout = schedule_timeout(msecs_to_jiffies(10000));
1686 snd_pcm_stream_lock_irq(substream);
1687 switch (runtime->status->state) {
1688 case SNDRV_PCM_STATE_SUSPENDED:
1689 err = -ESTRPIPE;
1690 goto _endloop;
1691 case SNDRV_PCM_STATE_XRUN:
1692 err = -EPIPE;
1693 goto _endloop;
1694 case SNDRV_PCM_STATE_DRAINING:
1695 if (is_playback)
1696 err = -EPIPE;
1697 else
1698 avail = 0; /* indicate draining */
1699 goto _endloop;
1700 case SNDRV_PCM_STATE_OPEN:
1701 case SNDRV_PCM_STATE_SETUP:
1702 case SNDRV_PCM_STATE_DISCONNECTED:
1703 err = -EBADFD;
1704 goto _endloop;
1706 if (!tout) {
1707 snd_printd("%s write error (DMA or IRQ trouble?)\n",
1708 is_playback ? "playback" : "capture");
1709 err = -EIO;
1710 break;
1712 if (is_playback)
1713 avail = snd_pcm_playback_avail(runtime);
1714 else
1715 avail = snd_pcm_capture_avail(runtime);
1716 if (avail >= runtime->control->avail_min)
1717 break;
1719 _endloop:
1720 remove_wait_queue(&runtime->sleep, &wait);
1721 *availp = avail;
1722 return err;
1725 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1726 unsigned int hwoff,
1727 unsigned long data, unsigned int off,
1728 snd_pcm_uframes_t frames)
1730 struct snd_pcm_runtime *runtime = substream->runtime;
1731 int err;
1732 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1733 if (substream->ops->copy) {
1734 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1735 return err;
1736 } else {
1737 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1738 if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1739 return -EFAULT;
1741 return 0;
1744 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1745 unsigned long data, unsigned int off,
1746 snd_pcm_uframes_t size);
1748 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1749 unsigned long data,
1750 snd_pcm_uframes_t size,
1751 int nonblock,
1752 transfer_f transfer)
1754 struct snd_pcm_runtime *runtime = substream->runtime;
1755 snd_pcm_uframes_t xfer = 0;
1756 snd_pcm_uframes_t offset = 0;
1757 int err = 0;
1759 if (size == 0)
1760 return 0;
1762 snd_pcm_stream_lock_irq(substream);
1763 switch (runtime->status->state) {
1764 case SNDRV_PCM_STATE_PREPARED:
1765 case SNDRV_PCM_STATE_RUNNING:
1766 case SNDRV_PCM_STATE_PAUSED:
1767 break;
1768 case SNDRV_PCM_STATE_XRUN:
1769 err = -EPIPE;
1770 goto _end_unlock;
1771 case SNDRV_PCM_STATE_SUSPENDED:
1772 err = -ESTRPIPE;
1773 goto _end_unlock;
1774 default:
1775 err = -EBADFD;
1776 goto _end_unlock;
1779 while (size > 0) {
1780 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1781 snd_pcm_uframes_t avail;
1782 snd_pcm_uframes_t cont;
1783 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1784 snd_pcm_update_hw_ptr(substream);
1785 avail = snd_pcm_playback_avail(runtime);
1786 if (!avail) {
1787 if (nonblock) {
1788 err = -EAGAIN;
1789 goto _end_unlock;
1791 err = wait_for_avail_min(substream, &avail);
1792 if (err < 0)
1793 goto _end_unlock;
1795 frames = size > avail ? avail : size;
1796 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1797 if (frames > cont)
1798 frames = cont;
1799 if (snd_BUG_ON(!frames)) {
1800 snd_pcm_stream_unlock_irq(substream);
1801 return -EINVAL;
1803 appl_ptr = runtime->control->appl_ptr;
1804 appl_ofs = appl_ptr % runtime->buffer_size;
1805 snd_pcm_stream_unlock_irq(substream);
1806 if ((err = transfer(substream, appl_ofs, data, offset, frames)) < 0)
1807 goto _end;
1808 snd_pcm_stream_lock_irq(substream);
1809 switch (runtime->status->state) {
1810 case SNDRV_PCM_STATE_XRUN:
1811 err = -EPIPE;
1812 goto _end_unlock;
1813 case SNDRV_PCM_STATE_SUSPENDED:
1814 err = -ESTRPIPE;
1815 goto _end_unlock;
1816 default:
1817 break;
1819 appl_ptr += frames;
1820 if (appl_ptr >= runtime->boundary)
1821 appl_ptr -= runtime->boundary;
1822 runtime->control->appl_ptr = appl_ptr;
1823 if (substream->ops->ack)
1824 substream->ops->ack(substream);
1826 offset += frames;
1827 size -= frames;
1828 xfer += frames;
1829 if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1830 snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1831 err = snd_pcm_start(substream);
1832 if (err < 0)
1833 goto _end_unlock;
1836 _end_unlock:
1837 snd_pcm_stream_unlock_irq(substream);
1838 _end:
1839 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
1842 /* sanity-check for read/write methods */
1843 static int pcm_sanity_check(struct snd_pcm_substream *substream)
1845 struct snd_pcm_runtime *runtime;
1846 if (PCM_RUNTIME_CHECK(substream))
1847 return -ENXIO;
1848 runtime = substream->runtime;
1849 if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
1850 return -EINVAL;
1851 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1852 return -EBADFD;
1853 return 0;
1856 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
1858 struct snd_pcm_runtime *runtime;
1859 int nonblock;
1860 int err;
1862 err = pcm_sanity_check(substream);
1863 if (err < 0)
1864 return err;
1865 runtime = substream->runtime;
1866 nonblock = !!(substream->f_flags & O_NONBLOCK);
1868 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
1869 runtime->channels > 1)
1870 return -EINVAL;
1871 return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
1872 snd_pcm_lib_write_transfer);
1875 EXPORT_SYMBOL(snd_pcm_lib_write);
1877 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
1878 unsigned int hwoff,
1879 unsigned long data, unsigned int off,
1880 snd_pcm_uframes_t frames)
1882 struct snd_pcm_runtime *runtime = substream->runtime;
1883 int err;
1884 void __user **bufs = (void __user **)data;
1885 int channels = runtime->channels;
1886 int c;
1887 if (substream->ops->copy) {
1888 if (snd_BUG_ON(!substream->ops->silence))
1889 return -EINVAL;
1890 for (c = 0; c < channels; ++c, ++bufs) {
1891 if (*bufs == NULL) {
1892 if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
1893 return err;
1894 } else {
1895 char __user *buf = *bufs + samples_to_bytes(runtime, off);
1896 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
1897 return err;
1900 } else {
1901 /* default transfer behaviour */
1902 size_t dma_csize = runtime->dma_bytes / channels;
1903 for (c = 0; c < channels; ++c, ++bufs) {
1904 char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
1905 if (*bufs == NULL) {
1906 snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
1907 } else {
1908 char __user *buf = *bufs + samples_to_bytes(runtime, off);
1909 if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
1910 return -EFAULT;
1914 return 0;
1917 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
1918 void __user **bufs,
1919 snd_pcm_uframes_t frames)
1921 struct snd_pcm_runtime *runtime;
1922 int nonblock;
1923 int err;
1925 err = pcm_sanity_check(substream);
1926 if (err < 0)
1927 return err;
1928 runtime = substream->runtime;
1929 nonblock = !!(substream->f_flags & O_NONBLOCK);
1931 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
1932 return -EINVAL;
1933 return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
1934 nonblock, snd_pcm_lib_writev_transfer);
1937 EXPORT_SYMBOL(snd_pcm_lib_writev);
1939 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
1940 unsigned int hwoff,
1941 unsigned long data, unsigned int off,
1942 snd_pcm_uframes_t frames)
1944 struct snd_pcm_runtime *runtime = substream->runtime;
1945 int err;
1946 char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1947 if (substream->ops->copy) {
1948 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1949 return err;
1950 } else {
1951 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1952 if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
1953 return -EFAULT;
1955 return 0;
1958 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
1959 unsigned long data,
1960 snd_pcm_uframes_t size,
1961 int nonblock,
1962 transfer_f transfer)
1964 struct snd_pcm_runtime *runtime = substream->runtime;
1965 snd_pcm_uframes_t xfer = 0;
1966 snd_pcm_uframes_t offset = 0;
1967 int err = 0;
1969 if (size == 0)
1970 return 0;
1972 snd_pcm_stream_lock_irq(substream);
1973 switch (runtime->status->state) {
1974 case SNDRV_PCM_STATE_PREPARED:
1975 if (size >= runtime->start_threshold) {
1976 err = snd_pcm_start(substream);
1977 if (err < 0)
1978 goto _end_unlock;
1980 break;
1981 case SNDRV_PCM_STATE_DRAINING:
1982 case SNDRV_PCM_STATE_RUNNING:
1983 case SNDRV_PCM_STATE_PAUSED:
1984 break;
1985 case SNDRV_PCM_STATE_XRUN:
1986 err = -EPIPE;
1987 goto _end_unlock;
1988 case SNDRV_PCM_STATE_SUSPENDED:
1989 err = -ESTRPIPE;
1990 goto _end_unlock;
1991 default:
1992 err = -EBADFD;
1993 goto _end_unlock;
1996 while (size > 0) {
1997 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1998 snd_pcm_uframes_t avail;
1999 snd_pcm_uframes_t cont;
2000 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2001 snd_pcm_update_hw_ptr(substream);
2002 avail = snd_pcm_capture_avail(runtime);
2003 if (!avail) {
2004 if (runtime->status->state ==
2005 SNDRV_PCM_STATE_DRAINING) {
2006 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2007 goto _end_unlock;
2009 if (nonblock) {
2010 err = -EAGAIN;
2011 goto _end_unlock;
2013 err = wait_for_avail_min(substream, &avail);
2014 if (err < 0)
2015 goto _end_unlock;
2016 if (!avail)
2017 continue; /* draining */
2019 frames = size > avail ? avail : size;
2020 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2021 if (frames > cont)
2022 frames = cont;
2023 if (snd_BUG_ON(!frames)) {
2024 snd_pcm_stream_unlock_irq(substream);
2025 return -EINVAL;
2027 appl_ptr = runtime->control->appl_ptr;
2028 appl_ofs = appl_ptr % runtime->buffer_size;
2029 snd_pcm_stream_unlock_irq(substream);
2030 if ((err = transfer(substream, appl_ofs, data, offset, frames)) < 0)
2031 goto _end;
2032 snd_pcm_stream_lock_irq(substream);
2033 switch (runtime->status->state) {
2034 case SNDRV_PCM_STATE_XRUN:
2035 err = -EPIPE;
2036 goto _end_unlock;
2037 case SNDRV_PCM_STATE_SUSPENDED:
2038 err = -ESTRPIPE;
2039 goto _end_unlock;
2040 default:
2041 break;
2043 appl_ptr += frames;
2044 if (appl_ptr >= runtime->boundary)
2045 appl_ptr -= runtime->boundary;
2046 runtime->control->appl_ptr = appl_ptr;
2047 if (substream->ops->ack)
2048 substream->ops->ack(substream);
2050 offset += frames;
2051 size -= frames;
2052 xfer += frames;
2054 _end_unlock:
2055 snd_pcm_stream_unlock_irq(substream);
2056 _end:
2057 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2060 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2062 struct snd_pcm_runtime *runtime;
2063 int nonblock;
2064 int err;
2066 err = pcm_sanity_check(substream);
2067 if (err < 0)
2068 return err;
2069 runtime = substream->runtime;
2070 nonblock = !!(substream->f_flags & O_NONBLOCK);
2071 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2072 return -EINVAL;
2073 return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2076 EXPORT_SYMBOL(snd_pcm_lib_read);
2078 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2079 unsigned int hwoff,
2080 unsigned long data, unsigned int off,
2081 snd_pcm_uframes_t frames)
2083 struct snd_pcm_runtime *runtime = substream->runtime;
2084 int err;
2085 void __user **bufs = (void __user **)data;
2086 int channels = runtime->channels;
2087 int c;
2088 if (substream->ops->copy) {
2089 for (c = 0; c < channels; ++c, ++bufs) {
2090 char __user *buf;
2091 if (*bufs == NULL)
2092 continue;
2093 buf = *bufs + samples_to_bytes(runtime, off);
2094 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2095 return err;
2097 } else {
2098 snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2099 for (c = 0; c < channels; ++c, ++bufs) {
2100 char *hwbuf;
2101 char __user *buf;
2102 if (*bufs == NULL)
2103 continue;
2105 hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2106 buf = *bufs + samples_to_bytes(runtime, off);
2107 if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2108 return -EFAULT;
2111 return 0;
2114 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2115 void __user **bufs,
2116 snd_pcm_uframes_t frames)
2118 struct snd_pcm_runtime *runtime;
2119 int nonblock;
2120 int err;
2122 err = pcm_sanity_check(substream);
2123 if (err < 0)
2124 return err;
2125 runtime = substream->runtime;
2126 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2127 return -EBADFD;
2129 nonblock = !!(substream->f_flags & O_NONBLOCK);
2130 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2131 return -EINVAL;
2132 return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2135 EXPORT_SYMBOL(snd_pcm_lib_readv);