1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Digital Audio (PCM) abstract layer
4 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5 * Abramo Bagnara <abramo@alsa-project.org>
6 */
7
8 #include <linux/slab.h>
9 #include <linux/sched/signal.h>
10 #include <linux/time.h>
11 #include <linux/math64.h>
12 #include <linux/export.h>
13 #include <sound/core.h>
14 #include <sound/control.h>
15 #include <sound/tlv.h>
16 #include <sound/info.h>
17 #include <sound/pcm.h>
18 #include <sound/pcm_params.h>
19 #include <sound/timer.h>
20
21 #include "pcm_local.h"
22
23 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
24 #define CREATE_TRACE_POINTS
25 #include "pcm_trace.h"
26 #else
27 #define trace_hwptr(substream, pos, in_interrupt)
28 #define trace_xrun(substream)
29 #define trace_hw_ptr_error(substream, reason)
30 #define trace_applptr(substream, prev, curr)
31 #endif
32
33 static int fill_silence_frames(struct snd_pcm_substream *substream,
34 snd_pcm_uframes_t off, snd_pcm_uframes_t frames);
35
36
37 static inline void update_silence_vars(struct snd_pcm_runtime *runtime,
38 snd_pcm_uframes_t ptr,
39 snd_pcm_uframes_t new_ptr)
40 {
41 snd_pcm_sframes_t delta;
42
43 delta = new_ptr - ptr;
44 if (delta == 0)
45 return;
46 if (delta < 0)
47 delta += runtime->boundary;
48 if ((snd_pcm_uframes_t)delta < runtime->silence_filled)
49 runtime->silence_filled -= delta;
50 else
51 runtime->silence_filled = 0;
52 runtime->silence_start = new_ptr;
53 }
54
55 /*
56 * fill ring buffer with silence
57 * runtime->silence_start: starting pointer to silence area
58 * runtime->silence_filled: size filled with silence
59 * runtime->silence_threshold: threshold from application
60 * runtime->silence_size: maximal size from application
61 *
62 * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
63 */
64 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
65 {
66 struct snd_pcm_runtime *runtime = substream->runtime;
67 snd_pcm_uframes_t frames, ofs, transfer;
68 int err;
69
70 if (runtime->silence_size < runtime->boundary) {
71 snd_pcm_sframes_t noise_dist;
72 snd_pcm_uframes_t appl_ptr = READ_ONCE(runtime->control->appl_ptr);
73 update_silence_vars(runtime, runtime->silence_start, appl_ptr);
74 /* initialization outside pointer updates */
75 if (new_hw_ptr == ULONG_MAX)
76 new_hw_ptr = runtime->status->hw_ptr;
77 /* get hw_avail with the boundary crossing */
78 noise_dist = appl_ptr - new_hw_ptr;
79 if (noise_dist < 0)
80 noise_dist += runtime->boundary;
81 /* total noise distance */
82 noise_dist += runtime->silence_filled;
83 if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
84 return;
85 frames = runtime->silence_threshold - noise_dist;
86 if (frames > runtime->silence_size)
87 frames = runtime->silence_size;
88 } else {
89 /*
90 * This filling mode aims at free-running mode (used for example by dmix),
91 * which doesn't update the application pointer.
92 */
93 snd_pcm_uframes_t hw_ptr = runtime->status->hw_ptr;
94 if (new_hw_ptr == ULONG_MAX) {
95 /*
96 * Initialization, fill the whole unused buffer with silence.
97 *
98 * Usually, this is entered while stopped, before data is queued,
99 * so both pointers are expected to be zero.
100 */
101 snd_pcm_sframes_t avail = runtime->control->appl_ptr - hw_ptr;
102 if (avail < 0)
103 avail += runtime->boundary;
104 /*
105 * In free-running mode, appl_ptr will be zero even while running,
106 * so we end up with a huge number. There is no useful way to
107 * handle this, so we just clear the whole buffer.
108 */
109 runtime->silence_filled = avail > runtime->buffer_size ? 0 : avail;
110 runtime->silence_start = hw_ptr;
111 } else {
112 /* Silence the just played area immediately */
113 update_silence_vars(runtime, hw_ptr, new_hw_ptr);
114 }
115 /*
116 * In this mode, silence_filled actually includes the valid
117 * sample data from the user.
118 */
119 frames = runtime->buffer_size - runtime->silence_filled;
120 }
121 if (snd_BUG_ON(frames > runtime->buffer_size))
122 return;
123 if (frames == 0)
124 return;
125 ofs = (runtime->silence_start + runtime->silence_filled) % runtime->buffer_size;
126 do {
127 transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
128 err = fill_silence_frames(substream, ofs, transfer);
129 snd_BUG_ON(err < 0);
130 runtime->silence_filled += transfer;
131 frames -= transfer;
132 ofs = 0;
133 } while (frames > 0);
134 snd_pcm_dma_buffer_sync(substream, SNDRV_DMA_SYNC_DEVICE);
135 }
136
137 #ifdef CONFIG_SND_DEBUG
138 void snd_pcm_debug_name(struct snd_pcm_substream *substream,
139 char *name, size_t len)
140 {
141 snprintf(name, len, "pcmC%dD%d%c:%d",
142 substream->pcm->card->number,
143 substream->pcm->device,
144 substream->stream ? 'c' : 'p',
145 substream->number);
146 }
147 EXPORT_SYMBOL(snd_pcm_debug_name);
148 #endif
149
150 #define XRUN_DEBUG_BASIC (1<<0)
151 #define XRUN_DEBUG_STACK (1<<1) /* dump also stack */
152 #define XRUN_DEBUG_JIFFIESCHECK (1<<2) /* do jiffies check */
153
154 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
155
156 #define xrun_debug(substream, mask) \
157 ((substream)->pstr->xrun_debug & (mask))
158 #else
159 #define xrun_debug(substream, mask) 0
160 #endif
161
162 #define dump_stack_on_xrun(substream) do { \
163 if (xrun_debug(substream, XRUN_DEBUG_STACK)) \
164 dump_stack(); \
165 } while (0)
166
167 /* call with stream lock held */
168 void __snd_pcm_xrun(struct snd_pcm_substream *substream)
169 {
170 struct snd_pcm_runtime *runtime = substream->runtime;
171
172 trace_xrun(substream);
173 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
174 struct timespec64 tstamp;
175
176 snd_pcm_gettime(runtime, &tstamp);
177 runtime->status->tstamp.tv_sec = tstamp.tv_sec;
178 runtime->status->tstamp.tv_nsec = tstamp.tv_nsec;
179 }
180 snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
181 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
182 char name[16];
183 snd_pcm_debug_name(substream, name, sizeof(name));
184 pcm_warn(substream->pcm, "XRUN: %s\n", name);
185 dump_stack_on_xrun(substream);
186 }
187 }
188
189 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
190 #define hw_ptr_error(substream, in_interrupt, reason, fmt, args...) \
191 do { \
192 trace_hw_ptr_error(substream, reason); \
193 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) { \
194 pr_err_ratelimited("ALSA: PCM: [%c] " reason ": " fmt, \
195 (in_interrupt) ? 'Q' : 'P', ##args); \
196 dump_stack_on_xrun(substream); \
197 } \
198 } while (0)
199
200 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
201
202 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
203
204 #endif
205
206 int snd_pcm_update_state(struct snd_pcm_substream *substream,
207 struct snd_pcm_runtime *runtime)
208 {
209 snd_pcm_uframes_t avail;
210
211 avail = snd_pcm_avail(substream);
212 if (avail > runtime->avail_max)
213 runtime->avail_max = avail;
214 if (runtime->state == SNDRV_PCM_STATE_DRAINING) {
215 if (avail >= runtime->buffer_size) {
216 snd_pcm_drain_done(substream);
217 return -EPIPE;
218 }
219 } else {
220 if (avail >= runtime->stop_threshold) {
221 __snd_pcm_xrun(substream);
222 return -EPIPE;
223 }
224 }
225 if (runtime->twake) {
226 if (avail >= runtime->twake)
227 wake_up(&runtime->tsleep);
228 } else if (avail >= runtime->control->avail_min)
229 wake_up(&runtime->sleep);
230 return 0;
231 }
232
233 static void update_audio_tstamp(struct snd_pcm_substream *substream,
234 struct timespec64 *curr_tstamp,
235 struct timespec64 *audio_tstamp)
236 {
237 struct snd_pcm_runtime *runtime = substream->runtime;
238 u64 audio_frames, audio_nsecs;
239 struct timespec64 driver_tstamp;
240
241 if (runtime->tstamp_mode != SNDRV_PCM_TSTAMP_ENABLE)
242 return;
243
244 if (!(substream->ops->get_time_info) ||
245 (runtime->audio_tstamp_report.actual_type ==
246 SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
247
248 /*
249 * provide audio timestamp derived from pointer position
250 * add delay only if requested
251 */
252
253 audio_frames = runtime->hw_ptr_wrap + runtime->status->hw_ptr;
254
255 if (runtime->audio_tstamp_config.report_delay) {
256 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
257 audio_frames -= runtime->delay;
258 else
259 audio_frames += runtime->delay;
260 }
261 audio_nsecs = div_u64(audio_frames * 1000000000LL,
262 runtime->rate);
263 *audio_tstamp = ns_to_timespec64(audio_nsecs);
264 }
265
266 if (runtime->status->audio_tstamp.tv_sec != audio_tstamp->tv_sec ||
267 runtime->status->audio_tstamp.tv_nsec != audio_tstamp->tv_nsec) {
268 runtime->status->audio_tstamp.tv_sec = audio_tstamp->tv_sec;
269 runtime->status->audio_tstamp.tv_nsec = audio_tstamp->tv_nsec;
270 runtime->status->tstamp.tv_sec = curr_tstamp->tv_sec;
271 runtime->status->tstamp.tv_nsec = curr_tstamp->tv_nsec;
272 }
273
274
275 /*
276 * re-take a driver timestamp to let apps detect if the reference tstamp
277 * read by low-level hardware was provided with a delay
278 */
279 snd_pcm_gettime(substream->runtime, &driver_tstamp);
280 runtime->driver_tstamp = driver_tstamp;
281 }
282
283 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
284 unsigned int in_interrupt)
285 {
286 struct snd_pcm_runtime *runtime = substream->runtime;
287 snd_pcm_uframes_t pos;
288 snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
289 snd_pcm_sframes_t hdelta, delta;
290 unsigned long jdelta;
291 unsigned long curr_jiffies;
292 struct timespec64 curr_tstamp;
293 struct timespec64 audio_tstamp;
294 int crossed_boundary = 0;
295
296 old_hw_ptr = runtime->status->hw_ptr;
297
298 /*
299 * group pointer, time and jiffies reads to allow for more
300 * accurate correlations/corrections.
301 * The values are stored at the end of this routine after
302 * corrections for hw_ptr position
303 */
304 pos = substream->ops->pointer(substream);
305 curr_jiffies = jiffies;
306 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
307 if ((substream->ops->get_time_info) &&
308 (runtime->audio_tstamp_config.type_requested != SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
309 substream->ops->get_time_info(substream, &curr_tstamp,
310 &audio_tstamp,
311 &runtime->audio_tstamp_config,
312 &runtime->audio_tstamp_report);
313
314 /* re-test in case tstamp type is not supported in hardware and was demoted to DEFAULT */
315 if (runtime->audio_tstamp_report.actual_type == SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)
316 snd_pcm_gettime(runtime, &curr_tstamp);
317 } else
318 snd_pcm_gettime(runtime, &curr_tstamp);
319 }
320
321 if (pos == SNDRV_PCM_POS_XRUN) {
322 __snd_pcm_xrun(substream);
323 return -EPIPE;
324 }
325 if (pos >= runtime->buffer_size) {
326 if (printk_ratelimit()) {
327 char name[16];
328 snd_pcm_debug_name(substream, name, sizeof(name));
329 pcm_err(substream->pcm,
330 "invalid position: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
331 name, pos, runtime->buffer_size,
332 runtime->period_size);
333 }
334 pos = 0;
335 }
336 pos -= pos % runtime->min_align;
337 trace_hwptr(substream, pos, in_interrupt);
338 hw_base = runtime->hw_ptr_base;
339 new_hw_ptr = hw_base + pos;
340 if (in_interrupt) {
341 /* we know that one period was processed */
342 /* delta = "expected next hw_ptr" for in_interrupt != 0 */
343 delta = runtime->hw_ptr_interrupt + runtime->period_size;
344 if (delta > new_hw_ptr) {
345 /* check for double acknowledged interrupts */
346 hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
347 if (hdelta > runtime->hw_ptr_buffer_jiffies/2 + 1) {
348 hw_base += runtime->buffer_size;
349 if (hw_base >= runtime->boundary) {
350 hw_base = 0;
351 crossed_boundary++;
352 }
353 new_hw_ptr = hw_base + pos;
354 goto __delta;
355 }
356 }
357 }
358 /* new_hw_ptr might be lower than old_hw_ptr in case when */
359 /* pointer crosses the end of the ring buffer */
360 if (new_hw_ptr < old_hw_ptr) {
361 hw_base += runtime->buffer_size;
362 if (hw_base >= runtime->boundary) {
363 hw_base = 0;
364 crossed_boundary++;
365 }
366 new_hw_ptr = hw_base + pos;
367 }
368 __delta:
369 delta = new_hw_ptr - old_hw_ptr;
370 if (delta < 0)
371 delta += runtime->boundary;
372
373 if (runtime->no_period_wakeup) {
374 snd_pcm_sframes_t xrun_threshold;
375 /*
376 * Without regular period interrupts, we have to check
377 * the elapsed time to detect xruns.
378 */
379 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
380 if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
381 goto no_delta_check;
382 hdelta = jdelta - delta * HZ / runtime->rate;
383 xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
384 while (hdelta > xrun_threshold) {
385 delta += runtime->buffer_size;
386 hw_base += runtime->buffer_size;
387 if (hw_base >= runtime->boundary) {
388 hw_base = 0;
389 crossed_boundary++;
390 }
391 new_hw_ptr = hw_base + pos;
392 hdelta -= runtime->hw_ptr_buffer_jiffies;
393 }
394 goto no_delta_check;
395 }
396
397 /* something must be really wrong */
398 if (delta >= runtime->buffer_size + runtime->period_size) {
399 hw_ptr_error(substream, in_interrupt, "Unexpected hw_ptr",
400 "(stream=%i, pos=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
401 substream->stream, (long)pos,
402 (long)new_hw_ptr, (long)old_hw_ptr);
403 return 0;
404 }
405
406 /* Do jiffies check only in xrun_debug mode */
407 if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
408 goto no_jiffies_check;
409
410 /* Skip the jiffies check for hardwares with BATCH flag.
411 * Such hardware usually just increases the position at each IRQ,
412 * thus it can't give any strange position.
413 */
414 if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
415 goto no_jiffies_check;
416 hdelta = delta;
417 if (hdelta < runtime->delay)
418 goto no_jiffies_check;
419 hdelta -= runtime->delay;
420 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
421 if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
422 delta = jdelta /
423 (((runtime->period_size * HZ) / runtime->rate)
424 + HZ/100);
425 /* move new_hw_ptr according jiffies not pos variable */
426 new_hw_ptr = old_hw_ptr;
427 hw_base = delta;
428 /* use loop to avoid checks for delta overflows */
429 /* the delta value is small or zero in most cases */
430 while (delta > 0) {
431 new_hw_ptr += runtime->period_size;
432 if (new_hw_ptr >= runtime->boundary) {
433 new_hw_ptr -= runtime->boundary;
434 crossed_boundary--;
435 }
436 delta--;
437 }
438 /* align hw_base to buffer_size */
439 hw_ptr_error(substream, in_interrupt, "hw_ptr skipping",
440 "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
441 (long)pos, (long)hdelta,
442 (long)runtime->period_size, jdelta,
443 ((hdelta * HZ) / runtime->rate), hw_base,
444 (unsigned long)old_hw_ptr,
445 (unsigned long)new_hw_ptr);
446 /* reset values to proper state */
447 delta = 0;
448 hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
449 }
450 no_jiffies_check:
451 if (delta > runtime->period_size + runtime->period_size / 2) {
452 hw_ptr_error(substream, in_interrupt,
453 "Lost interrupts?",
454 "(stream=%i, delta=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
455 substream->stream, (long)delta,
456 (long)new_hw_ptr,
457 (long)old_hw_ptr);
458 }
459
460 no_delta_check:
461 if (runtime->status->hw_ptr == new_hw_ptr) {
462 runtime->hw_ptr_jiffies = curr_jiffies;
463 update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
464 return 0;
465 }
466
467 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
468 runtime->silence_size > 0)
469 snd_pcm_playback_silence(substream, new_hw_ptr);
470
471 if (in_interrupt) {
472 delta = new_hw_ptr - runtime->hw_ptr_interrupt;
473 if (delta < 0)
474 delta += runtime->boundary;
475 delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
476 runtime->hw_ptr_interrupt += delta;
477 if (runtime->hw_ptr_interrupt >= runtime->boundary)
478 runtime->hw_ptr_interrupt -= runtime->boundary;
479 }
480 runtime->hw_ptr_base = hw_base;
481 runtime->status->hw_ptr = new_hw_ptr;
482 runtime->hw_ptr_jiffies = curr_jiffies;
483 if (crossed_boundary) {
484 snd_BUG_ON(crossed_boundary != 1);
485 runtime->hw_ptr_wrap += runtime->boundary;
486 }
487
488 update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
489
490 return snd_pcm_update_state(substream, runtime);
491 }
492
493 /* CAUTION: call it with irq disabled */
494 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
495 {
496 return snd_pcm_update_hw_ptr0(substream, 0);
497 }
498
499 /**
500 * snd_pcm_set_ops - set the PCM operators
501 * @pcm: the pcm instance
502 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
503 * @ops: the operator table
504 *
505 * Sets the given PCM operators to the pcm instance.
506 */
507 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
508 const struct snd_pcm_ops *ops)
509 {
510 struct snd_pcm_str *stream = &pcm->streams[direction];
511 struct snd_pcm_substream *substream;
512
513 for (substream = stream->substream; substream != NULL; substream = substream->next)
514 substream->ops = ops;
515 }
516 EXPORT_SYMBOL(snd_pcm_set_ops);
517
518 /**
519 * snd_pcm_set_sync_per_card - set the PCM sync id with card number
520 * @substream: the pcm substream
521 * @params: modified hardware parameters
522 * @id: identifier (max 12 bytes)
523 * @len: identifier length (max 12 bytes)
524 *
525 * Sets the PCM sync identifier for the card with zero padding.
526 *
527 * User space or any user should use this 16-byte identifier for a comparison only
528 * to check if two IDs are similar or different. Special case is the identifier
529 * containing only zeros. Interpretation for this combination is - empty (not set).
530 * The contents of the identifier should not be interpreted in any other way.
531 *
532 * The synchronization ID must be unique per clock source (usually one sound card,
533 * but multiple soundcard may use one PCM word clock source which means that they
534 * are fully synchronized).
535 *
536 * This routine composes this ID using card number in first four bytes and
537 * 12-byte additional ID. When other ID composition is used (e.g. for multiple
538 * sound cards), make sure that the composition does not clash with this
539 * composition scheme.
540 */
541 void snd_pcm_set_sync_per_card(struct snd_pcm_substream *substream,
542 struct snd_pcm_hw_params *params,
543 const unsigned char *id, unsigned int len)
544 {
545 *(__u32 *)params->sync = cpu_to_le32(substream->pcm->card->number);
546 len = min(12, len);
547 memcpy(params->sync + 4, id, len);
548 memset(params->sync + 4 + len, 0, 12 - len);
549 }
550 EXPORT_SYMBOL_GPL(snd_pcm_set_sync_per_card);
551
552 /*
553 * Standard ioctl routine
554 */
555
556 static inline unsigned int div32(unsigned int a, unsigned int b,
557 unsigned int *r)
558 {
559 if (b == 0) {
560 *r = 0;
561 return UINT_MAX;
562 }
563 *r = a % b;
564 return a / b;
565 }
566
567 static inline unsigned int div_down(unsigned int a, unsigned int b)
568 {
569 if (b == 0)
570 return UINT_MAX;
571 return a / b;
572 }
573
574 static inline unsigned int div_up(unsigned int a, unsigned int b)
575 {
576 unsigned int r;
577 unsigned int q;
578 if (b == 0)
579 return UINT_MAX;
580 q = div32(a, b, &r);
581 if (r)
582 ++q;
583 return q;
584 }
585
586 static inline unsigned int mul(unsigned int a, unsigned int b)
587 {
588 if (a == 0)
589 return 0;
590 if (div_down(UINT_MAX, a) < b)
591 return UINT_MAX;
592 return a * b;
593 }
594
595 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
596 unsigned int c, unsigned int *r)
597 {
598 u_int64_t n = (u_int64_t) a * b;
599 if (c == 0) {
600 *r = 0;
601 return UINT_MAX;
602 }
603 n = div_u64_rem(n, c, r);
604 if (n >= UINT_MAX) {
605 *r = 0;
606 return UINT_MAX;
607 }
608 return n;
609 }
610
611 /**
612 * snd_interval_refine - refine the interval value of configurator
613 * @i: the interval value to refine
614 * @v: the interval value to refer to
615 *
616 * Refines the interval value with the reference value.
617 * The interval is changed to the range satisfying both intervals.
618 * The interval status (min, max, integer, etc.) are evaluated.
619 *
620 * Return: Positive if the value is changed, zero if it's not changed, or a
621 * negative error code.
622 */
623 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
624 {
625 int changed = 0;
626 if (snd_BUG_ON(snd_interval_empty(i)))
627 return -EINVAL;
628 if (i->min < v->min) {
629 i->min = v->min;
630 i->openmin = v->openmin;
631 changed = 1;
632 } else if (i->min == v->min && !i->openmin && v->openmin) {
633 i->openmin = 1;
634 changed = 1;
635 }
636 if (i->max > v->max) {
637 i->max = v->max;
638 i->openmax = v->openmax;
639 changed = 1;
640 } else if (i->max == v->max && !i->openmax && v->openmax) {
641 i->openmax = 1;
642 changed = 1;
643 }
644 if (!i->integer && v->integer) {
645 i->integer = 1;
646 changed = 1;
647 }
648 if (i->integer) {
649 if (i->openmin) {
650 i->min++;
651 i->openmin = 0;
652 }
653 if (i->openmax) {
654 i->max--;
655 i->openmax = 0;
656 }
657 } else if (!i->openmin && !i->openmax && i->min == i->max)
658 i->integer = 1;
659 if (snd_interval_checkempty(i)) {
660 snd_interval_none(i);
661 return -EINVAL;
662 }
663 return changed;
664 }
665 EXPORT_SYMBOL(snd_interval_refine);
666
667 static int snd_interval_refine_first(struct snd_interval *i)
668 {
669 const unsigned int last_max = i->max;
670
671 if (snd_BUG_ON(snd_interval_empty(i)))
672 return -EINVAL;
673 if (snd_interval_single(i))
674 return 0;
675 i->max = i->min;
676 if (i->openmin)
677 i->max++;
678 /* only exclude max value if also excluded before refine */
679 i->openmax = (i->openmax && i->max >= last_max);
680 return 1;
681 }
682
683 static int snd_interval_refine_last(struct snd_interval *i)
684 {
685 const unsigned int last_min = i->min;
686
687 if (snd_BUG_ON(snd_interval_empty(i)))
688 return -EINVAL;
689 if (snd_interval_single(i))
690 return 0;
691 i->min = i->max;
692 if (i->openmax)
693 i->min--;
694 /* only exclude min value if also excluded before refine */
695 i->openmin = (i->openmin && i->min <= last_min);
696 return 1;
697 }
698
699 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
700 {
701 if (a->empty || b->empty) {
702 snd_interval_none(c);
703 return;
704 }
705 c->empty = 0;
706 c->min = mul(a->min, b->min);
707 c->openmin = (a->openmin || b->openmin);
708 c->max = mul(a->max, b->max);
709 c->openmax = (a->openmax || b->openmax);
710 c->integer = (a->integer && b->integer);
711 }
712
713 /**
714 * snd_interval_div - refine the interval value with division
715 * @a: dividend
716 * @b: divisor
717 * @c: quotient
718 *
719 * c = a / b
720 *
721 * Returns non-zero if the value is changed, zero if not changed.
722 */
723 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
724 {
725 unsigned int r;
726 if (a->empty || b->empty) {
727 snd_interval_none(c);
728 return;
729 }
730 c->empty = 0;
731 c->min = div32(a->min, b->max, &r);
732 c->openmin = (r || a->openmin || b->openmax);
733 if (b->min > 0) {
734 c->max = div32(a->max, b->min, &r);
735 if (r) {
736 c->max++;
737 c->openmax = 1;
738 } else
739 c->openmax = (a->openmax || b->openmin);
740 } else {
741 c->max = UINT_MAX;
742 c->openmax = 0;
743 }
744 c->integer = 0;
745 }
746
747 /**
748 * snd_interval_muldivk - refine the interval value
749 * @a: dividend 1
750 * @b: dividend 2
751 * @k: divisor (as integer)
752 * @c: result
753 *
754 * c = a * b / k
755 *
756 * Returns non-zero if the value is changed, zero if not changed.
757 */
758 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
759 unsigned int k, struct snd_interval *c)
760 {
761 unsigned int r;
762 if (a->empty || b->empty) {
763 snd_interval_none(c);
764 return;
765 }
766 c->empty = 0;
767 c->min = muldiv32(a->min, b->min, k, &r);
768 c->openmin = (r || a->openmin || b->openmin);
769 c->max = muldiv32(a->max, b->max, k, &r);
770 if (r) {
771 c->max++;
772 c->openmax = 1;
773 } else
774 c->openmax = (a->openmax || b->openmax);
775 c->integer = 0;
776 }
777
778 /**
779 * snd_interval_mulkdiv - refine the interval value
780 * @a: dividend 1
781 * @k: dividend 2 (as integer)
782 * @b: divisor
783 * @c: result
784 *
785 * c = a * k / b
786 *
787 * Returns non-zero if the value is changed, zero if not changed.
788 */
789 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
790 const struct snd_interval *b, struct snd_interval *c)
791 {
792 unsigned int r;
793 if (a->empty || b->empty) {
794 snd_interval_none(c);
795 return;
796 }
797 c->empty = 0;
798 c->min = muldiv32(a->min, k, b->max, &r);
799 c->openmin = (r || a->openmin || b->openmax);
800 if (b->min > 0) {
801 c->max = muldiv32(a->max, k, b->min, &r);
802 if (r) {
803 c->max++;
804 c->openmax = 1;
805 } else
806 c->openmax = (a->openmax || b->openmin);
807 } else {
808 c->max = UINT_MAX;
809 c->openmax = 0;
810 }
811 c->integer = 0;
812 }
813
814 /* ---- */
815
816
817 /**
818 * snd_interval_ratnum - refine the interval value
819 * @i: interval to refine
820 * @rats_count: number of ratnum_t
821 * @rats: ratnum_t array
822 * @nump: pointer to store the resultant numerator
823 * @denp: pointer to store the resultant denominator
824 *
825 * Return: Positive if the value is changed, zero if it's not changed, or a
826 * negative error code.
827 */
828 int snd_interval_ratnum(struct snd_interval *i,
829 unsigned int rats_count, const struct snd_ratnum *rats,
830 unsigned int *nump, unsigned int *denp)
831 {
832 unsigned int best_num, best_den;
833 int best_diff;
834 unsigned int k;
835 struct snd_interval t;
836 int err;
837 unsigned int result_num, result_den;
838 int result_diff;
839
840 best_num = best_den = best_diff = 0;
841 for (k = 0; k < rats_count; ++k) {
842 unsigned int num = rats[k].num;
843 unsigned int den;
844 unsigned int q = i->min;
845 int diff;
846 if (q == 0)
847 q = 1;
848 den = div_up(num, q);
849 if (den < rats[k].den_min)
850 continue;
851 if (den > rats[k].den_max)
852 den = rats[k].den_max;
853 else {
854 unsigned int r;
855 r = (den - rats[k].den_min) % rats[k].den_step;
856 if (r != 0)
857 den -= r;
858 }
859 diff = num - q * den;
860 if (diff < 0)
861 diff = -diff;
862 if (best_num == 0 ||
863 diff * best_den < best_diff * den) {
864 best_diff = diff;
865 best_den = den;
866 best_num = num;
867 }
868 }
869 if (best_den == 0) {
870 i->empty = 1;
871 return -EINVAL;
872 }
873 t.min = div_down(best_num, best_den);
874 t.openmin = !!(best_num % best_den);
875
876 result_num = best_num;
877 result_diff = best_diff;
878 result_den = best_den;
879 best_num = best_den = best_diff = 0;
880 for (k = 0; k < rats_count; ++k) {
881 unsigned int num = rats[k].num;
882 unsigned int den;
883 unsigned int q = i->max;
884 int diff;
885 if (q == 0) {
886 i->empty = 1;
887 return -EINVAL;
888 }
889 den = div_down(num, q);
890 if (den > rats[k].den_max)
891 continue;
892 if (den < rats[k].den_min)
893 den = rats[k].den_min;
894 else {
895 unsigned int r;
896 r = (den - rats[k].den_min) % rats[k].den_step;
897 if (r != 0)
898 den += rats[k].den_step - r;
899 }
900 diff = q * den - num;
901 if (diff < 0)
902 diff = -diff;
903 if (best_num == 0 ||
904 diff * best_den < best_diff * den) {
905 best_diff = diff;
906 best_den = den;
907 best_num = num;
908 }
909 }
910 if (best_den == 0) {
911 i->empty = 1;
912 return -EINVAL;
913 }
914 t.max = div_up(best_num, best_den);
915 t.openmax = !!(best_num % best_den);
916 t.integer = 0;
917 err = snd_interval_refine(i, &t);
918 if (err < 0)
919 return err;
920
921 if (snd_interval_single(i)) {
922 if (best_diff * result_den < result_diff * best_den) {
923 result_num = best_num;
924 result_den = best_den;
925 }
926 if (nump)
927 *nump = result_num;
928 if (denp)
929 *denp = result_den;
930 }
931 return err;
932 }
933 EXPORT_SYMBOL(snd_interval_ratnum);
934
935 /**
936 * snd_interval_ratden - refine the interval value
937 * @i: interval to refine
938 * @rats_count: number of struct ratden
939 * @rats: struct ratden array
940 * @nump: pointer to store the resultant numerator
941 * @denp: pointer to store the resultant denominator
942 *
943 * Return: Positive if the value is changed, zero if it's not changed, or a
944 * negative error code.
945 */
946 static int snd_interval_ratden(struct snd_interval *i,
947 unsigned int rats_count,
948 const struct snd_ratden *rats,
949 unsigned int *nump, unsigned int *denp)
950 {
951 unsigned int best_num, best_diff, best_den;
952 unsigned int k;
953 struct snd_interval t;
954 int err;
955
956 best_num = best_den = best_diff = 0;
957 for (k = 0; k < rats_count; ++k) {
958 unsigned int num;
959 unsigned int den = rats[k].den;
960 unsigned int q = i->min;
961 int diff;
962 num = mul(q, den);
963 if (num > rats[k].num_max)
964 continue;
965 if (num < rats[k].num_min)
966 num = rats[k].num_max;
967 else {
968 unsigned int r;
969 r = (num - rats[k].num_min) % rats[k].num_step;
970 if (r != 0)
971 num += rats[k].num_step - r;
972 }
973 diff = num - q * den;
974 if (best_num == 0 ||
975 diff * best_den < best_diff * den) {
976 best_diff = diff;
977 best_den = den;
978 best_num = num;
979 }
980 }
981 if (best_den == 0) {
982 i->empty = 1;
983 return -EINVAL;
984 }
985 t.min = div_down(best_num, best_den);
986 t.openmin = !!(best_num % best_den);
987
988 best_num = best_den = best_diff = 0;
989 for (k = 0; k < rats_count; ++k) {
990 unsigned int num;
991 unsigned int den = rats[k].den;
992 unsigned int q = i->max;
993 int diff;
994 num = mul(q, den);
995 if (num < rats[k].num_min)
996 continue;
997 if (num > rats[k].num_max)
998 num = rats[k].num_max;
999 else {
1000 unsigned int r;
1001 r = (num - rats[k].num_min) % rats[k].num_step;
1002 if (r != 0)
1003 num -= r;
1004 }
1005 diff = q * den - num;
1006 if (best_num == 0 ||
1007 diff * best_den < best_diff * den) {
1008 best_diff = diff;
1009 best_den = den;
1010 best_num = num;
1011 }
1012 }
1013 if (best_den == 0) {
1014 i->empty = 1;
1015 return -EINVAL;
1016 }
1017 t.max = div_up(best_num, best_den);
1018 t.openmax = !!(best_num % best_den);
1019 t.integer = 0;
1020 err = snd_interval_refine(i, &t);
1021 if (err < 0)
1022 return err;
1023
1024 if (snd_interval_single(i)) {
1025 if (nump)
1026 *nump = best_num;
1027 if (denp)
1028 *denp = best_den;
1029 }
1030 return err;
1031 }
1032
1033 /**
1034 * snd_interval_list - refine the interval value from the list
1035 * @i: the interval value to refine
1036 * @count: the number of elements in the list
1037 * @list: the value list
1038 * @mask: the bit-mask to evaluate
1039 *
1040 * Refines the interval value from the list.
1041 * When mask is non-zero, only the elements corresponding to bit 1 are
1042 * evaluated.
1043 *
1044 * Return: Positive if the value is changed, zero if it's not changed, or a
1045 * negative error code.
1046 */
1047 int snd_interval_list(struct snd_interval *i, unsigned int count,
1048 const unsigned int *list, unsigned int mask)
1049 {
1050 unsigned int k;
1051 struct snd_interval list_range;
1052
1053 if (!count) {
1054 i->empty = 1;
1055 return -EINVAL;
1056 }
1057 snd_interval_any(&list_range);
1058 list_range.min = UINT_MAX;
1059 list_range.max = 0;
1060 for (k = 0; k < count; k++) {
1061 if (mask && !(mask & (1 << k)))
1062 continue;
1063 if (!snd_interval_test(i, list[k]))
1064 continue;
1065 list_range.min = min(list_range.min, list[k]);
1066 list_range.max = max(list_range.max, list[k]);
1067 }
1068 return snd_interval_refine(i, &list_range);
1069 }
1070 EXPORT_SYMBOL(snd_interval_list);
1071
1072 /**
1073 * snd_interval_ranges - refine the interval value from the list of ranges
1074 * @i: the interval value to refine
1075 * @count: the number of elements in the list of ranges
1076 * @ranges: the ranges list
1077 * @mask: the bit-mask to evaluate
1078 *
1079 * Refines the interval value from the list of ranges.
1080 * When mask is non-zero, only the elements corresponding to bit 1 are
1081 * evaluated.
1082 *
1083 * Return: Positive if the value is changed, zero if it's not changed, or a
1084 * negative error code.
1085 */
1086 int snd_interval_ranges(struct snd_interval *i, unsigned int count,
1087 const struct snd_interval *ranges, unsigned int mask)
1088 {
1089 unsigned int k;
1090 struct snd_interval range_union;
1091 struct snd_interval range;
1092
1093 if (!count) {
1094 snd_interval_none(i);
1095 return -EINVAL;
1096 }
1097 snd_interval_any(&range_union);
1098 range_union.min = UINT_MAX;
1099 range_union.max = 0;
1100 for (k = 0; k < count; k++) {
1101 if (mask && !(mask & (1 << k)))
1102 continue;
1103 snd_interval_copy(&range, &ranges[k]);
1104 if (snd_interval_refine(&range, i) < 0)
1105 continue;
1106 if (snd_interval_empty(&range))
1107 continue;
1108
1109 if (range.min < range_union.min) {
1110 range_union.min = range.min;
1111 range_union.openmin = 1;
1112 }
1113 if (range.min == range_union.min && !range.openmin)
1114 range_union.openmin = 0;
1115 if (range.max > range_union.max) {
1116 range_union.max = range.max;
1117 range_union.openmax = 1;
1118 }
1119 if (range.max == range_union.max && !range.openmax)
1120 range_union.openmax = 0;
1121 }
1122 return snd_interval_refine(i, &range_union);
1123 }
1124 EXPORT_SYMBOL(snd_interval_ranges);
1125
1126 static int snd_interval_step(struct snd_interval *i, unsigned int step)
1127 {
1128 unsigned int n;
1129 int changed = 0;
1130 n = i->min % step;
1131 if (n != 0 || i->openmin) {
1132 i->min += step - n;
1133 i->openmin = 0;
1134 changed = 1;
1135 }
1136 n = i->max % step;
1137 if (n != 0 || i->openmax) {
1138 i->max -= n;
1139 i->openmax = 0;
1140 changed = 1;
1141 }
1142 if (snd_interval_checkempty(i)) {
1143 i->empty = 1;
1144 return -EINVAL;
1145 }
1146 return changed;
1147 }
1148
1149 /* Info constraints helpers */
1150
1151 /**
1152 * snd_pcm_hw_rule_add - add the hw-constraint rule
1153 * @runtime: the pcm runtime instance
1154 * @cond: condition bits
1155 * @var: the variable to evaluate
1156 * @func: the evaluation function
1157 * @private: the private data pointer passed to function
1158 * @dep: the dependent variables
1159 *
1160 * Return: Zero if successful, or a negative error code on failure.
1161 */
1162 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1163 int var,
1164 snd_pcm_hw_rule_func_t func, void *private,
1165 int dep, ...)
1166 {
1167 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1168 struct snd_pcm_hw_rule *c;
1169 unsigned int k;
1170 va_list args;
1171 va_start(args, dep);
1172 if (constrs->rules_num >= constrs->rules_all) {
1173 struct snd_pcm_hw_rule *new;
1174 unsigned int new_rules = constrs->rules_all + 16;
1175 new = krealloc_array(constrs->rules, new_rules,
1176 sizeof(*c), GFP_KERNEL);
1177 if (!new) {
1178 va_end(args);
1179 return -ENOMEM;
1180 }
1181 constrs->rules = new;
1182 constrs->rules_all = new_rules;
1183 }
1184 c = &constrs->rules[constrs->rules_num];
1185 c->cond = cond;
1186 c->func = func;
1187 c->var = var;
1188 c->private = private;
1189 k = 0;
1190 while (1) {
1191 if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1192 va_end(args);
1193 return -EINVAL;
1194 }
1195 c->deps[k++] = dep;
1196 if (dep < 0)
1197 break;
1198 dep = va_arg(args, int);
1199 }
1200 constrs->rules_num++;
1201 va_end(args);
1202 return 0;
1203 }
1204 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1205
1206 /**
1207 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1208 * @runtime: PCM runtime instance
1209 * @var: hw_params variable to apply the mask
1210 * @mask: the bitmap mask
1211 *
1212 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1213 *
1214 * Return: Zero if successful, or a negative error code on failure.
1215 */
1216 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1217 u_int32_t mask)
1218 {
1219 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1220 struct snd_mask *maskp = constrs_mask(constrs, var);
1221 *maskp->bits &= mask;
1222 memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1223 if (*maskp->bits == 0)
1224 return -EINVAL;
1225 return 0;
1226 }
1227
1228 /**
1229 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1230 * @runtime: PCM runtime instance
1231 * @var: hw_params variable to apply the mask
1232 * @mask: the 64bit bitmap mask
1233 *
1234 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1235 *
1236 * Return: Zero if successful, or a negative error code on failure.
1237 */
1238 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1239 u_int64_t mask)
1240 {
1241 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1242 struct snd_mask *maskp = constrs_mask(constrs, var);
1243 maskp->bits[0] &= (u_int32_t)mask;
1244 maskp->bits[1] &= (u_int32_t)(mask >> 32);
1245 memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1246 if (! maskp->bits[0] && ! maskp->bits[1])
1247 return -EINVAL;
1248 return 0;
1249 }
1250 EXPORT_SYMBOL(snd_pcm_hw_constraint_mask64);
1251
1252 /**
1253 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1254 * @runtime: PCM runtime instance
1255 * @var: hw_params variable to apply the integer constraint
1256 *
1257 * Apply the constraint of integer to an interval parameter.
1258 *
1259 * Return: Positive if the value is changed, zero if it's not changed, or a
1260 * negative error code.
1261 */
1262 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1263 {
1264 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1265 return snd_interval_setinteger(constrs_interval(constrs, var));
1266 }
1267 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1268
1269 /**
1270 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1271 * @runtime: PCM runtime instance
1272 * @var: hw_params variable to apply the range
1273 * @min: the minimal value
1274 * @max: the maximal value
1275 *
1276 * Apply the min/max range constraint to an interval parameter.
1277 *
1278 * Return: Positive if the value is changed, zero if it's not changed, or a
1279 * negative error code.
1280 */
1281 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1282 unsigned int min, unsigned int max)
1283 {
1284 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1285 struct snd_interval t;
1286 t.min = min;
1287 t.max = max;
1288 t.openmin = t.openmax = 0;
1289 t.integer = 0;
1290 return snd_interval_refine(constrs_interval(constrs, var), &t);
1291 }
1292 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1293
1294 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1295 struct snd_pcm_hw_rule *rule)
1296 {
1297 struct snd_pcm_hw_constraint_list *list = rule->private;
1298 return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1299 }
1300
1301
1302 /**
1303 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1304 * @runtime: PCM runtime instance
1305 * @cond: condition bits
1306 * @var: hw_params variable to apply the list constraint
1307 * @l: list
1308 *
1309 * Apply the list of constraints to an interval parameter.
1310 *
1311 * Return: Zero if successful, or a negative error code on failure.
1312 */
1313 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1314 unsigned int cond,
1315 snd_pcm_hw_param_t var,
1316 const struct snd_pcm_hw_constraint_list *l)
1317 {
1318 return snd_pcm_hw_rule_add(runtime, cond, var,
1319 snd_pcm_hw_rule_list, (void *)l,
1320 var, -1);
1321 }
1322 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1323
1324 static int snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params *params,
1325 struct snd_pcm_hw_rule *rule)
1326 {
1327 struct snd_pcm_hw_constraint_ranges *r = rule->private;
1328 return snd_interval_ranges(hw_param_interval(params, rule->var),
1329 r->count, r->ranges, r->mask);
1330 }
1331
1332
1333 /**
1334 * snd_pcm_hw_constraint_ranges - apply list of range constraints to a parameter
1335 * @runtime: PCM runtime instance
1336 * @cond: condition bits
1337 * @var: hw_params variable to apply the list of range constraints
1338 * @r: ranges
1339 *
1340 * Apply the list of range constraints to an interval parameter.
1341 *
1342 * Return: Zero if successful, or a negative error code on failure.
1343 */
1344 int snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime *runtime,
1345 unsigned int cond,
1346 snd_pcm_hw_param_t var,
1347 const struct snd_pcm_hw_constraint_ranges *r)
1348 {
1349 return snd_pcm_hw_rule_add(runtime, cond, var,
1350 snd_pcm_hw_rule_ranges, (void *)r,
1351 var, -1);
1352 }
1353 EXPORT_SYMBOL(snd_pcm_hw_constraint_ranges);
1354
1355 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1356 struct snd_pcm_hw_rule *rule)
1357 {
1358 const struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1359 unsigned int num = 0, den = 0;
1360 int err;
1361 err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1362 r->nrats, r->rats, &num, &den);
1363 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1364 params->rate_num = num;
1365 params->rate_den = den;
1366 }
1367 return err;
1368 }
1369
1370 /**
1371 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1372 * @runtime: PCM runtime instance
1373 * @cond: condition bits
1374 * @var: hw_params variable to apply the ratnums constraint
1375 * @r: struct snd_ratnums constriants
1376 *
1377 * Return: Zero if successful, or a negative error code on failure.
1378 */
1379 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1380 unsigned int cond,
1381 snd_pcm_hw_param_t var,
1382 const struct snd_pcm_hw_constraint_ratnums *r)
1383 {
1384 return snd_pcm_hw_rule_add(runtime, cond, var,
1385 snd_pcm_hw_rule_ratnums, (void *)r,
1386 var, -1);
1387 }
1388 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1389
1390 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1391 struct snd_pcm_hw_rule *rule)
1392 {
1393 const struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1394 unsigned int num = 0, den = 0;
1395 int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1396 r->nrats, r->rats, &num, &den);
1397 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1398 params->rate_num = num;
1399 params->rate_den = den;
1400 }
1401 return err;
1402 }
1403
1404 /**
1405 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1406 * @runtime: PCM runtime instance
1407 * @cond: condition bits
1408 * @var: hw_params variable to apply the ratdens constraint
1409 * @r: struct snd_ratdens constriants
1410 *
1411 * Return: Zero if successful, or a negative error code on failure.
1412 */
1413 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1414 unsigned int cond,
1415 snd_pcm_hw_param_t var,
1416 const struct snd_pcm_hw_constraint_ratdens *r)
1417 {
1418 return snd_pcm_hw_rule_add(runtime, cond, var,
1419 snd_pcm_hw_rule_ratdens, (void *)r,
1420 var, -1);
1421 }
1422 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1423
1424 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1425 struct snd_pcm_hw_rule *rule)
1426 {
1427 unsigned int l = (unsigned long) rule->private;
1428 int width = l & 0xffff;
1429 unsigned int msbits = l >> 16;
1430 const struct snd_interval *i =
1431 hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1432
1433 if (!snd_interval_single(i))
1434 return 0;
1435
1436 if ((snd_interval_value(i) == width) ||
1437 (width == 0 && snd_interval_value(i) > msbits))
1438 params->msbits = min_not_zero(params->msbits, msbits);
1439
1440 return 0;
1441 }
1442
1443 /**
1444 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1445 * @runtime: PCM runtime instance
1446 * @cond: condition bits
1447 * @width: sample bits width
1448 * @msbits: msbits width
1449 *
1450 * This constraint will set the number of most significant bits (msbits) if a
1451 * sample format with the specified width has been select. If width is set to 0
1452 * the msbits will be set for any sample format with a width larger than the
1453 * specified msbits.
1454 *
1455 * Return: Zero if successful, or a negative error code on failure.
1456 */
1457 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1458 unsigned int cond,
1459 unsigned int width,
1460 unsigned int msbits)
1461 {
1462 unsigned long l = (msbits << 16) | width;
1463 return snd_pcm_hw_rule_add(runtime, cond, -1,
1464 snd_pcm_hw_rule_msbits,
1465 (void*) l,
1466 SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1467 }
1468 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1469
1470 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1471 struct snd_pcm_hw_rule *rule)
1472 {
1473 unsigned long step = (unsigned long) rule->private;
1474 return snd_interval_step(hw_param_interval(params, rule->var), step);
1475 }
1476
1477 /**
1478 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1479 * @runtime: PCM runtime instance
1480 * @cond: condition bits
1481 * @var: hw_params variable to apply the step constraint
1482 * @step: step size
1483 *
1484 * Return: Zero if successful, or a negative error code on failure.
1485 */
1486 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1487 unsigned int cond,
1488 snd_pcm_hw_param_t var,
1489 unsigned long step)
1490 {
1491 return snd_pcm_hw_rule_add(runtime, cond, var,
1492 snd_pcm_hw_rule_step, (void *) step,
1493 var, -1);
1494 }
1495 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1496
1497 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1498 {
1499 static const unsigned int pow2_sizes[] = {
1500 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1501 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1502 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1503 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1504 };
1505 return snd_interval_list(hw_param_interval(params, rule->var),
1506 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1507 }
1508
1509 /**
1510 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1511 * @runtime: PCM runtime instance
1512 * @cond: condition bits
1513 * @var: hw_params variable to apply the power-of-2 constraint
1514 *
1515 * Return: Zero if successful, or a negative error code on failure.
1516 */
1517 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1518 unsigned int cond,
1519 snd_pcm_hw_param_t var)
1520 {
1521 return snd_pcm_hw_rule_add(runtime, cond, var,
1522 snd_pcm_hw_rule_pow2, NULL,
1523 var, -1);
1524 }
1525 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1526
1527 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1528 struct snd_pcm_hw_rule *rule)
1529 {
1530 unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1531 struct snd_interval *rate;
1532
1533 rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1534 return snd_interval_list(rate, 1, &base_rate, 0);
1535 }
1536
1537 /**
1538 * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1539 * @runtime: PCM runtime instance
1540 * @base_rate: the rate at which the hardware does not resample
1541 *
1542 * Return: Zero if successful, or a negative error code on failure.
1543 */
1544 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1545 unsigned int base_rate)
1546 {
1547 return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1548 SNDRV_PCM_HW_PARAM_RATE,
1549 snd_pcm_hw_rule_noresample_func,
1550 (void *)(uintptr_t)base_rate,
1551 SNDRV_PCM_HW_PARAM_RATE, -1);
1552 }
1553 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1554
1555 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1556 snd_pcm_hw_param_t var)
1557 {
1558 if (hw_is_mask(var)) {
1559 snd_mask_any(hw_param_mask(params, var));
1560 params->cmask |= 1 << var;
1561 params->rmask |= 1 << var;
1562 return;
1563 }
1564 if (hw_is_interval(var)) {
1565 snd_interval_any(hw_param_interval(params, var));
1566 params->cmask |= 1 << var;
1567 params->rmask |= 1 << var;
1568 return;
1569 }
1570 snd_BUG();
1571 }
1572
1573 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1574 {
1575 unsigned int k;
1576 memset(params, 0, sizeof(*params));
1577 for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1578 _snd_pcm_hw_param_any(params, k);
1579 for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1580 _snd_pcm_hw_param_any(params, k);
1581 params->info = ~0U;
1582 }
1583 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1584
1585 /**
1586 * snd_pcm_hw_param_value - return @params field @var value
1587 * @params: the hw_params instance
1588 * @var: parameter to retrieve
1589 * @dir: pointer to the direction (-1,0,1) or %NULL
1590 *
1591 * Return: The value for field @var if it's fixed in configuration space
1592 * defined by @params. -%EINVAL otherwise.
1593 */
1594 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1595 snd_pcm_hw_param_t var, int *dir)
1596 {
1597 if (hw_is_mask(var)) {
1598 const struct snd_mask *mask = hw_param_mask_c(params, var);
1599 if (!snd_mask_single(mask))
1600 return -EINVAL;
1601 if (dir)
1602 *dir = 0;
1603 return snd_mask_value(mask);
1604 }
1605 if (hw_is_interval(var)) {
1606 const struct snd_interval *i = hw_param_interval_c(params, var);
1607 if (!snd_interval_single(i))
1608 return -EINVAL;
1609 if (dir)
1610 *dir = i->openmin;
1611 return snd_interval_value(i);
1612 }
1613 return -EINVAL;
1614 }
1615 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1616
1617 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1618 snd_pcm_hw_param_t var)
1619 {
1620 if (hw_is_mask(var)) {
1621 snd_mask_none(hw_param_mask(params, var));
1622 params->cmask |= 1 << var;
1623 params->rmask |= 1 << var;
1624 } else if (hw_is_interval(var)) {
1625 snd_interval_none(hw_param_interval(params, var));
1626 params->cmask |= 1 << var;
1627 params->rmask |= 1 << var;
1628 } else {
1629 snd_BUG();
1630 }
1631 }
1632 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1633
1634 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1635 snd_pcm_hw_param_t var)
1636 {
1637 int changed;
1638 if (hw_is_mask(var))
1639 changed = snd_mask_refine_first(hw_param_mask(params, var));
1640 else if (hw_is_interval(var))
1641 changed = snd_interval_refine_first(hw_param_interval(params, var));
1642 else
1643 return -EINVAL;
1644 if (changed > 0) {
1645 params->cmask |= 1 << var;
1646 params->rmask |= 1 << var;
1647 }
1648 return changed;
1649 }
1650
1651
1652 /**
1653 * snd_pcm_hw_param_first - refine config space and return minimum value
1654 * @pcm: PCM instance
1655 * @params: the hw_params instance
1656 * @var: parameter to retrieve
1657 * @dir: pointer to the direction (-1,0,1) or %NULL
1658 *
1659 * Inside configuration space defined by @params remove from @var all
1660 * values > minimum. Reduce configuration space accordingly.
1661 *
1662 * Return: The minimum, or a negative error code on failure.
1663 */
1664 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1665 struct snd_pcm_hw_params *params,
1666 snd_pcm_hw_param_t var, int *dir)
1667 {
1668 int changed = _snd_pcm_hw_param_first(params, var);
1669 if (changed < 0)
1670 return changed;
1671 if (params->rmask) {
1672 int err = snd_pcm_hw_refine(pcm, params);
1673 if (err < 0)
1674 return err;
1675 }
1676 return snd_pcm_hw_param_value(params, var, dir);
1677 }
1678 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1679
1680 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1681 snd_pcm_hw_param_t var)
1682 {
1683 int changed;
1684 if (hw_is_mask(var))
1685 changed = snd_mask_refine_last(hw_param_mask(params, var));
1686 else if (hw_is_interval(var))
1687 changed = snd_interval_refine_last(hw_param_interval(params, var));
1688 else
1689 return -EINVAL;
1690 if (changed > 0) {
1691 params->cmask |= 1 << var;
1692 params->rmask |= 1 << var;
1693 }
1694 return changed;
1695 }
1696
1697
1698 /**
1699 * snd_pcm_hw_param_last - refine config space and return maximum value
1700 * @pcm: PCM instance
1701 * @params: the hw_params instance
1702 * @var: parameter to retrieve
1703 * @dir: pointer to the direction (-1,0,1) or %NULL
1704 *
1705 * Inside configuration space defined by @params remove from @var all
1706 * values < maximum. Reduce configuration space accordingly.
1707 *
1708 * Return: The maximum, or a negative error code on failure.
1709 */
1710 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1711 struct snd_pcm_hw_params *params,
1712 snd_pcm_hw_param_t var, int *dir)
1713 {
1714 int changed = _snd_pcm_hw_param_last(params, var);
1715 if (changed < 0)
1716 return changed;
1717 if (params->rmask) {
1718 int err = snd_pcm_hw_refine(pcm, params);
1719 if (err < 0)
1720 return err;
1721 }
1722 return snd_pcm_hw_param_value(params, var, dir);
1723 }
1724 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1725
1726 /**
1727 * snd_pcm_hw_params_bits - Get the number of bits per the sample.
1728 * @p: hardware parameters
1729 *
1730 * Return: The number of bits per sample based on the format,
1731 * subformat and msbits the specified hw params has.
1732 */
1733 int snd_pcm_hw_params_bits(const struct snd_pcm_hw_params *p)
1734 {
1735 snd_pcm_subformat_t subformat = params_subformat(p);
1736 snd_pcm_format_t format = params_format(p);
1737
1738 switch (format) {
1739 case SNDRV_PCM_FORMAT_S32_LE:
1740 case SNDRV_PCM_FORMAT_U32_LE:
1741 case SNDRV_PCM_FORMAT_S32_BE:
1742 case SNDRV_PCM_FORMAT_U32_BE:
1743 switch (subformat) {
1744 case SNDRV_PCM_SUBFORMAT_MSBITS_20:
1745 return 20;
1746 case SNDRV_PCM_SUBFORMAT_MSBITS_24:
1747 return 24;
1748 case SNDRV_PCM_SUBFORMAT_MSBITS_MAX:
1749 case SNDRV_PCM_SUBFORMAT_STD:
1750 default:
1751 break;
1752 }
1753 fallthrough;
1754 default:
1755 return snd_pcm_format_width(format);
1756 }
1757 }
1758 EXPORT_SYMBOL(snd_pcm_hw_params_bits);
1759
1760 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1761 void *arg)
1762 {
1763 struct snd_pcm_runtime *runtime = substream->runtime;
1764
1765 guard(pcm_stream_lock_irqsave)(substream);
1766 if (snd_pcm_running(substream) &&
1767 snd_pcm_update_hw_ptr(substream) >= 0)
1768 runtime->status->hw_ptr %= runtime->buffer_size;
1769 else {
1770 runtime->status->hw_ptr = 0;
1771 runtime->hw_ptr_wrap = 0;
1772 }
1773 return 0;
1774 }
1775
1776 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1777 void *arg)
1778 {
1779 struct snd_pcm_channel_info *info = arg;
1780 struct snd_pcm_runtime *runtime = substream->runtime;
1781 int width;
1782 if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1783 info->offset = -1;
1784 return 0;
1785 }
1786 width = snd_pcm_format_physical_width(runtime->format);
1787 if (width < 0)
1788 return width;
1789 info->offset = 0;
1790 switch (runtime->access) {
1791 case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1792 case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1793 info->first = info->channel * width;
1794 info->step = runtime->channels * width;
1795 break;
1796 case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1797 case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1798 {
1799 size_t size = runtime->dma_bytes / runtime->channels;
1800 info->first = info->channel * size * 8;
1801 info->step = width;
1802 break;
1803 }
1804 default:
1805 snd_BUG();
1806 break;
1807 }
1808 return 0;
1809 }
1810
1811 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1812 void *arg)
1813 {
1814 struct snd_pcm_hw_params *params = arg;
1815 snd_pcm_format_t format;
1816 int channels;
1817 ssize_t frame_size;
1818
1819 params->fifo_size = substream->runtime->hw.fifo_size;
1820 if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1821 format = params_format(params);
1822 channels = params_channels(params);
1823 frame_size = snd_pcm_format_size(format, channels);
1824 if (frame_size > 0)
1825 params->fifo_size /= frame_size;
1826 }
1827 return 0;
1828 }
1829
1830 static int snd_pcm_lib_ioctl_sync_id(struct snd_pcm_substream *substream,
1831 void *arg)
1832 {
1833 static const unsigned char id[12] = { 0xff, 0xff, 0xff, 0xff,
1834 0xff, 0xff, 0xff, 0xff,
1835 0xff, 0xff, 0xff, 0xff };
1836
1837 if (substream->runtime->std_sync_id)
1838 snd_pcm_set_sync_per_card(substream, arg, id, sizeof(id));
1839 return 0;
1840 }
1841
1842 /**
1843 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1844 * @substream: the pcm substream instance
1845 * @cmd: ioctl command
1846 * @arg: ioctl argument
1847 *
1848 * Processes the generic ioctl commands for PCM.
1849 * Can be passed as the ioctl callback for PCM ops.
1850 *
1851 * Return: Zero if successful, or a negative error code on failure.
1852 */
1853 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1854 unsigned int cmd, void *arg)
1855 {
1856 switch (cmd) {
1857 case SNDRV_PCM_IOCTL1_RESET:
1858 return snd_pcm_lib_ioctl_reset(substream, arg);
1859 case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1860 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1861 case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1862 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1863 case SNDRV_PCM_IOCTL1_SYNC_ID:
1864 return snd_pcm_lib_ioctl_sync_id(substream, arg);
1865 }
1866 return -ENXIO;
1867 }
1868 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1869
1870 /**
1871 * snd_pcm_period_elapsed_under_stream_lock() - update the status of runtime for the next period
1872 * under acquired lock of PCM substream.
1873 * @substream: the instance of pcm substream.
1874 *
1875 * This function is called when the batch of audio data frames as the same size as the period of
1876 * buffer is already processed in audio data transmission.
1877 *
1878 * The call of function updates the status of runtime with the latest position of audio data
1879 * transmission, checks overrun and underrun over buffer, awaken user processes from waiting for
1880 * available audio data frames, sampling audio timestamp, and performs stop or drain the PCM
1881 * substream according to configured threshold.
1882 *
1883 * The function is intended to use for the case that PCM driver operates audio data frames under
1884 * acquired lock of PCM substream; e.g. in callback of any operation of &snd_pcm_ops in process
1885 * context. In any interrupt context, it's preferrable to use ``snd_pcm_period_elapsed()`` instead
1886 * since lock of PCM substream should be acquired in advance.
1887 *
1888 * Developer should pay enough attention that some callbacks in &snd_pcm_ops are done by the call of
1889 * function:
1890 *
1891 * - .pointer - to retrieve current position of audio data transmission by frame count or XRUN state.
1892 * - .trigger - with SNDRV_PCM_TRIGGER_STOP at XRUN or DRAINING state.
1893 * - .get_time_info - to retrieve audio time stamp if needed.
1894 *
1895 * Even if more than one periods have elapsed since the last call, you have to call this only once.
1896 */
1897 void snd_pcm_period_elapsed_under_stream_lock(struct snd_pcm_substream *substream)
1898 {
1899 struct snd_pcm_runtime *runtime;
1900
1901 if (PCM_RUNTIME_CHECK(substream))
1902 return;
1903 runtime = substream->runtime;
1904
1905 if (!snd_pcm_running(substream) ||
1906 snd_pcm_update_hw_ptr0(substream, 1) < 0)
1907 goto _end;
1908
1909 #ifdef CONFIG_SND_PCM_TIMER
1910 if (substream->timer_running)
1911 snd_timer_interrupt(substream->timer, 1);
1912 #endif
1913 _end:
1914 snd_kill_fasync(runtime->fasync, SIGIO, POLL_IN);
1915 }
1916 EXPORT_SYMBOL(snd_pcm_period_elapsed_under_stream_lock);
1917
1918 /**
1919 * snd_pcm_period_elapsed() - update the status of runtime for the next period by acquiring lock of
1920 * PCM substream.
1921 * @substream: the instance of PCM substream.
1922 *
1923 * This function is mostly similar to ``snd_pcm_period_elapsed_under_stream_lock()`` except for
1924 * acquiring lock of PCM substream voluntarily.
1925 *
1926 * It's typically called by any type of IRQ handler when hardware IRQ occurs to notify event that
1927 * the batch of audio data frames as the same size as the period of buffer is already processed in
1928 * audio data transmission.
1929 */
1930 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1931 {
1932 if (snd_BUG_ON(!substream))
1933 return;
1934
1935 guard(pcm_stream_lock_irqsave)(substream);
1936 snd_pcm_period_elapsed_under_stream_lock(substream);
1937 }
1938 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1939
1940 /*
1941 * Wait until avail_min data becomes available
1942 * Returns a negative error code if any error occurs during operation.
1943 * The available space is stored on availp. When err = 0 and avail = 0
1944 * on the capture stream, it indicates the stream is in DRAINING state.
1945 */
1946 static int wait_for_avail(struct snd_pcm_substream *substream,
1947 snd_pcm_uframes_t *availp)
1948 {
1949 struct snd_pcm_runtime *runtime = substream->runtime;
1950 int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1951 wait_queue_entry_t wait;
1952 int err = 0;
1953 snd_pcm_uframes_t avail = 0;
1954 long wait_time, tout;
1955
1956 init_waitqueue_entry(&wait, current);
1957 set_current_state(TASK_INTERRUPTIBLE);
1958 add_wait_queue(&runtime->tsleep, &wait);
1959
1960 if (runtime->no_period_wakeup)
1961 wait_time = MAX_SCHEDULE_TIMEOUT;
1962 else {
1963 /* use wait time from substream if available */
1964 if (substream->wait_time) {
1965 wait_time = substream->wait_time;
1966 } else {
1967 wait_time = 100;
1968
1969 if (runtime->rate) {
1970 long t = runtime->buffer_size * 1100 / runtime->rate;
1971 wait_time = max(t, wait_time);
1972 }
1973 }
1974 wait_time = msecs_to_jiffies(wait_time);
1975 }
1976
1977 for (;;) {
1978 if (signal_pending(current)) {
1979 err = -ERESTARTSYS;
1980 break;
1981 }
1982
1983 /*
1984 * We need to check if space became available already
1985 * (and thus the wakeup happened already) first to close
1986 * the race of space already having become available.
1987 * This check must happen after been added to the waitqueue
1988 * and having current state be INTERRUPTIBLE.
1989 */
1990 avail = snd_pcm_avail(substream);
1991 if (avail >= runtime->twake)
1992 break;
1993 snd_pcm_stream_unlock_irq(substream);
1994
1995 tout = schedule_timeout(wait_time);
1996
1997 snd_pcm_stream_lock_irq(substream);
1998 set_current_state(TASK_INTERRUPTIBLE);
1999 switch (runtime->state) {
2000 case SNDRV_PCM_STATE_SUSPENDED:
2001 err = -ESTRPIPE;
2002 goto _endloop;
2003 case SNDRV_PCM_STATE_XRUN:
2004 err = -EPIPE;
2005 goto _endloop;
2006 case SNDRV_PCM_STATE_DRAINING:
2007 if (is_playback)
2008 err = -EPIPE;
2009 else
2010 avail = 0; /* indicate draining */
2011 goto _endloop;
2012 case SNDRV_PCM_STATE_OPEN:
2013 case SNDRV_PCM_STATE_SETUP:
2014 case SNDRV_PCM_STATE_DISCONNECTED:
2015 err = -EBADFD;
2016 goto _endloop;
2017 case SNDRV_PCM_STATE_PAUSED:
2018 continue;
2019 }
2020 if (!tout) {
2021 pcm_dbg(substream->pcm,
2022 "%s timeout (DMA or IRQ trouble?)\n",
2023 is_playback ? "playback write" : "capture read");
2024 err = -EIO;
2025 break;
2026 }
2027 }
2028 _endloop:
2029 set_current_state(TASK_RUNNING);
2030 remove_wait_queue(&runtime->tsleep, &wait);
2031 *availp = avail;
2032 return err;
2033 }
2034
2035 typedef int (*pcm_transfer_f)(struct snd_pcm_substream *substream,
2036 int channel, unsigned long hwoff,
2037 struct iov_iter *iter, unsigned long bytes);
2038
2039 typedef int (*pcm_copy_f)(struct snd_pcm_substream *, snd_pcm_uframes_t, void *,
2040 snd_pcm_uframes_t, snd_pcm_uframes_t, pcm_transfer_f,
2041 bool);
2042
2043 /* calculate the target DMA-buffer position to be written/read */
2044 static void *get_dma_ptr(struct snd_pcm_runtime *runtime,
2045 int channel, unsigned long hwoff)
2046 {
2047 return runtime->dma_area + hwoff +
2048 channel * (runtime->dma_bytes / runtime->channels);
2049 }
2050
2051 /* default copy ops for write; used for both interleaved and non- modes */
2052 static int default_write_copy(struct snd_pcm_substream *substream,
2053 int channel, unsigned long hwoff,
2054 struct iov_iter *iter, unsigned long bytes)
2055 {
2056 if (copy_from_iter(get_dma_ptr(substream->runtime, channel, hwoff),
2057 bytes, iter) != bytes)
2058 return -EFAULT;
2059 return 0;
2060 }
2061
2062 /* fill silence instead of copy data; called as a transfer helper
2063 * from __snd_pcm_lib_write() or directly from noninterleaved_copy() when
2064 * a NULL buffer is passed
2065 */
2066 static int fill_silence(struct snd_pcm_substream *substream, int channel,
2067 unsigned long hwoff, struct iov_iter *iter,
2068 unsigned long bytes)
2069 {
2070 struct snd_pcm_runtime *runtime = substream->runtime;
2071
2072 if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
2073 return 0;
2074 if (substream->ops->fill_silence)
2075 return substream->ops->fill_silence(substream, channel,
2076 hwoff, bytes);
2077
2078 snd_pcm_format_set_silence(runtime->format,
2079 get_dma_ptr(runtime, channel, hwoff),
2080 bytes_to_samples(runtime, bytes));
2081 return 0;
2082 }
2083
2084 /* default copy ops for read; used for both interleaved and non- modes */
2085 static int default_read_copy(struct snd_pcm_substream *substream,
2086 int channel, unsigned long hwoff,
2087 struct iov_iter *iter, unsigned long bytes)
2088 {
2089 if (copy_to_iter(get_dma_ptr(substream->runtime, channel, hwoff),
2090 bytes, iter) != bytes)
2091 return -EFAULT;
2092 return 0;
2093 }
2094
2095 /* call transfer with the filled iov_iter */
2096 static int do_transfer(struct snd_pcm_substream *substream, int c,
2097 unsigned long hwoff, void *data, unsigned long bytes,
2098 pcm_transfer_f transfer, bool in_kernel)
2099 {
2100 struct iov_iter iter;
2101 int err, type;
2102
2103 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
2104 type = ITER_SOURCE;
2105 else
2106 type = ITER_DEST;
2107
2108 if (in_kernel) {
2109 struct kvec kvec = { data, bytes };
2110
2111 iov_iter_kvec(&iter, type, &kvec, 1, bytes);
2112 return transfer(substream, c, hwoff, &iter, bytes);
2113 }
2114
2115 err = import_ubuf(type, (__force void __user *)data, bytes, &iter);
2116 if (err)
2117 return err;
2118 return transfer(substream, c, hwoff, &iter, bytes);
2119 }
2120
2121 /* call transfer function with the converted pointers and sizes;
2122 * for interleaved mode, it's one shot for all samples
2123 */
2124 static int interleaved_copy(struct snd_pcm_substream *substream,
2125 snd_pcm_uframes_t hwoff, void *data,
2126 snd_pcm_uframes_t off,
2127 snd_pcm_uframes_t frames,
2128 pcm_transfer_f transfer,
2129 bool in_kernel)
2130 {
2131 struct snd_pcm_runtime *runtime = substream->runtime;
2132
2133 /* convert to bytes */
2134 hwoff = frames_to_bytes(runtime, hwoff);
2135 off = frames_to_bytes(runtime, off);
2136 frames = frames_to_bytes(runtime, frames);
2137
2138 return do_transfer(substream, 0, hwoff, data + off, frames, transfer,
2139 in_kernel);
2140 }
2141
2142 /* call transfer function with the converted pointers and sizes for each
2143 * non-interleaved channel; when buffer is NULL, silencing instead of copying
2144 */
2145 static int noninterleaved_copy(struct snd_pcm_substream *substream,
2146 snd_pcm_uframes_t hwoff, void *data,
2147 snd_pcm_uframes_t off,
2148 snd_pcm_uframes_t frames,
2149 pcm_transfer_f transfer,
2150 bool in_kernel)
2151 {
2152 struct snd_pcm_runtime *runtime = substream->runtime;
2153 int channels = runtime->channels;
2154 void **bufs = data;
2155 int c, err;
2156
2157 /* convert to bytes; note that it's not frames_to_bytes() here.
2158 * in non-interleaved mode, we copy for each channel, thus
2159 * each copy is n_samples bytes x channels = whole frames.
2160 */
2161 off = samples_to_bytes(runtime, off);
2162 frames = samples_to_bytes(runtime, frames);
2163 hwoff = samples_to_bytes(runtime, hwoff);
2164 for (c = 0; c < channels; ++c, ++bufs) {
2165 if (!data || !*bufs)
2166 err = fill_silence(substream, c, hwoff, NULL, frames);
2167 else
2168 err = do_transfer(substream, c, hwoff, *bufs + off,
2169 frames, transfer, in_kernel);
2170 if (err < 0)
2171 return err;
2172 }
2173 return 0;
2174 }
2175
2176 /* fill silence on the given buffer position;
2177 * called from snd_pcm_playback_silence()
2178 */
2179 static int fill_silence_frames(struct snd_pcm_substream *substream,
2180 snd_pcm_uframes_t off, snd_pcm_uframes_t frames)
2181 {
2182 if (substream->runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
2183 substream->runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED)
2184 return interleaved_copy(substream, off, NULL, 0, frames,
2185 fill_silence, true);
2186 else
2187 return noninterleaved_copy(substream, off, NULL, 0, frames,
2188 fill_silence, true);
2189 }
2190
2191 /* sanity-check for read/write methods */
2192 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2193 {
2194 struct snd_pcm_runtime *runtime;
2195 if (PCM_RUNTIME_CHECK(substream))
2196 return -ENXIO;
2197 runtime = substream->runtime;
2198 if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
2199 return -EINVAL;
2200 if (runtime->state == SNDRV_PCM_STATE_OPEN)
2201 return -EBADFD;
2202 return 0;
2203 }
2204
2205 static int pcm_accessible_state(struct snd_pcm_runtime *runtime)
2206 {
2207 switch (runtime->state) {
2208 case SNDRV_PCM_STATE_PREPARED:
2209 case SNDRV_PCM_STATE_RUNNING:
2210 case SNDRV_PCM_STATE_PAUSED:
2211 return 0;
2212 case SNDRV_PCM_STATE_XRUN:
2213 return -EPIPE;
2214 case SNDRV_PCM_STATE_SUSPENDED:
2215 return -ESTRPIPE;
2216 default:
2217 return -EBADFD;
2218 }
2219 }
2220
2221 /* update to the given appl_ptr and call ack callback if needed;
2222 * when an error is returned, take back to the original value
2223 */
2224 int pcm_lib_apply_appl_ptr(struct snd_pcm_substream *substream,
2225 snd_pcm_uframes_t appl_ptr)
2226 {
2227 struct snd_pcm_runtime *runtime = substream->runtime;
2228 snd_pcm_uframes_t old_appl_ptr = runtime->control->appl_ptr;
2229 snd_pcm_sframes_t diff;
2230 int ret;
2231
2232 if (old_appl_ptr == appl_ptr)
2233 return 0;
2234
2235 if (appl_ptr >= runtime->boundary)
2236 return -EINVAL;
2237 /*
2238 * check if a rewind is requested by the application
2239 */
2240 if (substream->runtime->info & SNDRV_PCM_INFO_NO_REWINDS) {
2241 diff = appl_ptr - old_appl_ptr;
2242 if (diff >= 0) {
2243 if (diff > runtime->buffer_size)
2244 return -EINVAL;
2245 } else {
2246 if (runtime->boundary + diff > runtime->buffer_size)
2247 return -EINVAL;
2248 }
2249 }
2250
2251 runtime->control->appl_ptr = appl_ptr;
2252 if (substream->ops->ack) {
2253 ret = substream->ops->ack(substream);
2254 if (ret < 0) {
2255 runtime->control->appl_ptr = old_appl_ptr;
2256 if (ret == -EPIPE)
2257 __snd_pcm_xrun(substream);
2258 return ret;
2259 }
2260 }
2261
2262 trace_applptr(substream, old_appl_ptr, appl_ptr);
2263
2264 return 0;
2265 }
2266
2267 /* the common loop for read/write data */
2268 snd_pcm_sframes_t __snd_pcm_lib_xfer(struct snd_pcm_substream *substream,
2269 void *data, bool interleaved,
2270 snd_pcm_uframes_t size, bool in_kernel)
2271 {
2272 struct snd_pcm_runtime *runtime = substream->runtime;
2273 snd_pcm_uframes_t xfer = 0;
2274 snd_pcm_uframes_t offset = 0;
2275 snd_pcm_uframes_t avail;
2276 pcm_copy_f writer;
2277 pcm_transfer_f transfer;
2278 bool nonblock;
2279 bool is_playback;
2280 int err;
2281
2282 err = pcm_sanity_check(substream);
2283 if (err < 0)
2284 return err;
2285
2286 is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
2287 if (interleaved) {
2288 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2289 runtime->channels > 1)
2290 return -EINVAL;
2291 writer = interleaved_copy;
2292 } else {
2293 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2294 return -EINVAL;
2295 writer = noninterleaved_copy;
2296 }
2297
2298 if (!data) {
2299 if (is_playback)
2300 transfer = fill_silence;
2301 else
2302 return -EINVAL;
2303 } else {
2304 if (substream->ops->copy)
2305 transfer = substream->ops->copy;
2306 else
2307 transfer = is_playback ?
2308 default_write_copy : default_read_copy;
2309 }
2310
2311 if (size == 0)
2312 return 0;
2313
2314 nonblock = !!(substream->f_flags & O_NONBLOCK);
2315
2316 snd_pcm_stream_lock_irq(substream);
2317 err = pcm_accessible_state(runtime);
2318 if (err < 0)
2319 goto _end_unlock;
2320
2321 runtime->twake = runtime->control->avail_min ? : 1;
2322 if (runtime->state == SNDRV_PCM_STATE_RUNNING)
2323 snd_pcm_update_hw_ptr(substream);
2324
2325 /*
2326 * If size < start_threshold, wait indefinitely. Another
2327 * thread may start capture
2328 */
2329 if (!is_playback &&
2330 runtime->state == SNDRV_PCM_STATE_PREPARED &&
2331 size >= runtime->start_threshold) {
2332 err = snd_pcm_start(substream);
2333 if (err < 0)
2334 goto _end_unlock;
2335 }
2336
2337 avail = snd_pcm_avail(substream);
2338
2339 while (size > 0) {
2340 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2341 snd_pcm_uframes_t cont;
2342 if (!avail) {
2343 if (!is_playback &&
2344 runtime->state == SNDRV_PCM_STATE_DRAINING) {
2345 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2346 goto _end_unlock;
2347 }
2348 if (nonblock) {
2349 err = -EAGAIN;
2350 goto _end_unlock;
2351 }
2352 runtime->twake = min_t(snd_pcm_uframes_t, size,
2353 runtime->control->avail_min ? : 1);
2354 err = wait_for_avail(substream, &avail);
2355 if (err < 0)
2356 goto _end_unlock;
2357 if (!avail)
2358 continue; /* draining */
2359 }
2360 frames = size > avail ? avail : size;
2361 appl_ptr = READ_ONCE(runtime->control->appl_ptr);
2362 appl_ofs = appl_ptr % runtime->buffer_size;
2363 cont = runtime->buffer_size - appl_ofs;
2364 if (frames > cont)
2365 frames = cont;
2366 if (snd_BUG_ON(!frames)) {
2367 err = -EINVAL;
2368 goto _end_unlock;
2369 }
2370 if (!atomic_inc_unless_negative(&runtime->buffer_accessing)) {
2371 err = -EBUSY;
2372 goto _end_unlock;
2373 }
2374 snd_pcm_stream_unlock_irq(substream);
2375 if (!is_playback)
2376 snd_pcm_dma_buffer_sync(substream, SNDRV_DMA_SYNC_CPU);
2377 err = writer(substream, appl_ofs, data, offset, frames,
2378 transfer, in_kernel);
2379 if (is_playback)
2380 snd_pcm_dma_buffer_sync(substream, SNDRV_DMA_SYNC_DEVICE);
2381 snd_pcm_stream_lock_irq(substream);
2382 atomic_dec(&runtime->buffer_accessing);
2383 if (err < 0)
2384 goto _end_unlock;
2385 err = pcm_accessible_state(runtime);
2386 if (err < 0)
2387 goto _end_unlock;
2388 appl_ptr += frames;
2389 if (appl_ptr >= runtime->boundary)
2390 appl_ptr -= runtime->boundary;
2391 err = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2392 if (err < 0)
2393 goto _end_unlock;
2394
2395 offset += frames;
2396 size -= frames;
2397 xfer += frames;
2398 avail -= frames;
2399 if (is_playback &&
2400 runtime->state == SNDRV_PCM_STATE_PREPARED &&
2401 snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2402 err = snd_pcm_start(substream);
2403 if (err < 0)
2404 goto _end_unlock;
2405 }
2406 }
2407 _end_unlock:
2408 runtime->twake = 0;
2409 if (xfer > 0 && err >= 0)
2410 snd_pcm_update_state(substream, runtime);
2411 snd_pcm_stream_unlock_irq(substream);
2412 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2413 }
2414 EXPORT_SYMBOL(__snd_pcm_lib_xfer);
2415
2416 /*
2417 * standard channel mapping helpers
2418 */
2419
2420 /* default channel maps for multi-channel playbacks, up to 8 channels */
2421 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2422 { .channels = 1,
2423 .map = { SNDRV_CHMAP_MONO } },
2424 { .channels = 2,
2425 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2426 { .channels = 4,
2427 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2428 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2429 { .channels = 6,
2430 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2431 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2432 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2433 { .channels = 8,
2434 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2435 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2436 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2437 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2438 { }
2439 };
2440 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2441
2442 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2443 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2444 { .channels = 1,
2445 .map = { SNDRV_CHMAP_MONO } },
2446 { .channels = 2,
2447 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2448 { .channels = 4,
2449 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2450 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2451 { .channels = 6,
2452 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2453 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2454 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2455 { .channels = 8,
2456 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2457 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2458 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2459 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2460 { }
2461 };
2462 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2463
2464 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2465 {
2466 if (ch > info->max_channels)
2467 return false;
2468 return !info->channel_mask || (info->channel_mask & (1U << ch));
2469 }
2470
2471 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2472 struct snd_ctl_elem_info *uinfo)
2473 {
2474 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2475
2476 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2477 uinfo->count = info->max_channels;
2478 uinfo->value.integer.min = 0;
2479 uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2480 return 0;
2481 }
2482
2483 /* get callback for channel map ctl element
2484 * stores the channel position firstly matching with the current channels
2485 */
2486 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2487 struct snd_ctl_elem_value *ucontrol)
2488 {
2489 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2490 unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2491 struct snd_pcm_substream *substream;
2492 const struct snd_pcm_chmap_elem *map;
2493
2494 if (!info->chmap)
2495 return -EINVAL;
2496 substream = snd_pcm_chmap_substream(info, idx);
2497 if (!substream)
2498 return -ENODEV;
2499 memset(ucontrol->value.integer.value, 0,
2500 sizeof(long) * info->max_channels);
2501 if (!substream->runtime)
2502 return 0; /* no channels set */
2503 for (map = info->chmap; map->channels; map++) {
2504 int i;
2505 if (map->channels == substream->runtime->channels &&
2506 valid_chmap_channels(info, map->channels)) {
2507 for (i = 0; i < map->channels; i++)
2508 ucontrol->value.integer.value[i] = map->map[i];
2509 return 0;
2510 }
2511 }
2512 return -EINVAL;
2513 }
2514
2515 /* tlv callback for channel map ctl element
2516 * expands the pre-defined channel maps in a form of TLV
2517 */
2518 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2519 unsigned int size, unsigned int __user *tlv)
2520 {
2521 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2522 const struct snd_pcm_chmap_elem *map;
2523 unsigned int __user *dst;
2524 int c, count = 0;
2525
2526 if (!info->chmap)
2527 return -EINVAL;
2528 if (size < 8)
2529 return -ENOMEM;
2530 if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2531 return -EFAULT;
2532 size -= 8;
2533 dst = tlv + 2;
2534 for (map = info->chmap; map->channels; map++) {
2535 int chs_bytes = map->channels * 4;
2536 if (!valid_chmap_channels(info, map->channels))
2537 continue;
2538 if (size < 8)
2539 return -ENOMEM;
2540 if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2541 put_user(chs_bytes, dst + 1))
2542 return -EFAULT;
2543 dst += 2;
2544 size -= 8;
2545 count += 8;
2546 if (size < chs_bytes)
2547 return -ENOMEM;
2548 size -= chs_bytes;
2549 count += chs_bytes;
2550 for (c = 0; c < map->channels; c++) {
2551 if (put_user(map->map[c], dst))
2552 return -EFAULT;
2553 dst++;
2554 }
2555 }
2556 if (put_user(count, tlv + 1))
2557 return -EFAULT;
2558 return 0;
2559 }
2560
2561 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2562 {
2563 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2564 info->pcm->streams[info->stream].chmap_kctl = NULL;
2565 kfree(info);
2566 }
2567
2568 /**
2569 * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2570 * @pcm: the assigned PCM instance
2571 * @stream: stream direction
2572 * @chmap: channel map elements (for query)
2573 * @max_channels: the max number of channels for the stream
2574 * @private_value: the value passed to each kcontrol's private_value field
2575 * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2576 *
2577 * Create channel-mapping control elements assigned to the given PCM stream(s).
2578 * Return: Zero if successful, or a negative error value.
2579 */
2580 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2581 const struct snd_pcm_chmap_elem *chmap,
2582 int max_channels,
2583 unsigned long private_value,
2584 struct snd_pcm_chmap **info_ret)
2585 {
2586 struct snd_pcm_chmap *info;
2587 struct snd_kcontrol_new knew = {
2588 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
2589 .access = SNDRV_CTL_ELEM_ACCESS_READ |
2590 SNDRV_CTL_ELEM_ACCESS_VOLATILE |
2591 SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2592 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2593 .info = pcm_chmap_ctl_info,
2594 .get = pcm_chmap_ctl_get,
2595 .tlv.c = pcm_chmap_ctl_tlv,
2596 };
2597 int err;
2598
2599 if (WARN_ON(pcm->streams[stream].chmap_kctl))
2600 return -EBUSY;
2601 info = kzalloc(sizeof(*info), GFP_KERNEL);
2602 if (!info)
2603 return -ENOMEM;
2604 info->pcm = pcm;
2605 info->stream = stream;
2606 info->chmap = chmap;
2607 info->max_channels = max_channels;
2608 if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2609 knew.name = "Playback Channel Map";
2610 else
2611 knew.name = "Capture Channel Map";
2612 knew.device = pcm->device;
2613 knew.count = pcm->streams[stream].substream_count;
2614 knew.private_value = private_value;
2615 info->kctl = snd_ctl_new1(&knew, info);
2616 if (!info->kctl) {
2617 kfree(info);
2618 return -ENOMEM;
2619 }
2620 info->kctl->private_free = pcm_chmap_ctl_private_free;
2621 err = snd_ctl_add(pcm->card, info->kctl);
2622 if (err < 0)
2623 return err;
2624 pcm->streams[stream].chmap_kctl = info->kctl;
2625 if (info_ret)
2626 *info_ret = info;
2627 return 0;
2628 }
2629 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);
2630
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.