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 * fill ring buffer with silence
38 * runtime->silence_start: starting pointer to silence area
39 * runtime->silence_filled: size filled with silence
40 * runtime->silence_threshold: threshold from application
41 * runtime->silence_size: maximal size from application
42 *
43 * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
44 */
snd_pcm_playback_silence(struct snd_pcm_substream * substream,snd_pcm_uframes_t new_hw_ptr)45 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
46 {
47 struct snd_pcm_runtime *runtime = substream->runtime;
48 snd_pcm_uframes_t frames, ofs, transfer;
49 int err;
50
51 if (runtime->silence_size < runtime->boundary) {
52 snd_pcm_sframes_t noise_dist, n;
53 snd_pcm_uframes_t appl_ptr = READ_ONCE(runtime->control->appl_ptr);
54 if (runtime->silence_start != appl_ptr) {
55 n = appl_ptr - runtime->silence_start;
56 if (n < 0)
57 n += runtime->boundary;
58 if ((snd_pcm_uframes_t)n < runtime->silence_filled)
59 runtime->silence_filled -= n;
60 else
61 runtime->silence_filled = 0;
62 runtime->silence_start = appl_ptr;
63 }
64 if (runtime->silence_filled >= runtime->buffer_size)
65 return;
66 noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
67 if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
68 return;
69 frames = runtime->silence_threshold - noise_dist;
70 if (frames > runtime->silence_size)
71 frames = runtime->silence_size;
72 } else {
73 if (new_hw_ptr == ULONG_MAX) { /* initialization */
74 snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
75 if (avail > runtime->buffer_size)
76 avail = runtime->buffer_size;
77 runtime->silence_filled = avail > 0 ? avail : 0;
78 runtime->silence_start = (runtime->status->hw_ptr +
79 runtime->silence_filled) %
80 runtime->boundary;
81 } else {
82 ofs = runtime->status->hw_ptr;
83 frames = new_hw_ptr - ofs;
84 if ((snd_pcm_sframes_t)frames < 0)
85 frames += runtime->boundary;
86 runtime->silence_filled -= frames;
87 if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
88 runtime->silence_filled = 0;
89 runtime->silence_start = new_hw_ptr;
90 } else {
91 runtime->silence_start = ofs;
92 }
93 }
94 frames = runtime->buffer_size - runtime->silence_filled;
95 }
96 if (snd_BUG_ON(frames > runtime->buffer_size))
97 return;
98 if (frames == 0)
99 return;
100 ofs = runtime->silence_start % runtime->buffer_size;
101 while (frames > 0) {
102 transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
103 err = fill_silence_frames(substream, ofs, transfer);
104 snd_BUG_ON(err < 0);
105 runtime->silence_filled += transfer;
106 frames -= transfer;
107 ofs = 0;
108 }
109 }
110
111 #ifdef CONFIG_SND_DEBUG
snd_pcm_debug_name(struct snd_pcm_substream * substream,char * name,size_t len)112 void snd_pcm_debug_name(struct snd_pcm_substream *substream,
113 char *name, size_t len)
114 {
115 snprintf(name, len, "pcmC%dD%d%c:%d",
116 substream->pcm->card->number,
117 substream->pcm->device,
118 substream->stream ? 'c' : 'p',
119 substream->number);
120 }
121 EXPORT_SYMBOL(snd_pcm_debug_name);
122 #endif
123
124 #define XRUN_DEBUG_BASIC (1<<0)
125 #define XRUN_DEBUG_STACK (1<<1) /* dump also stack */
126 #define XRUN_DEBUG_JIFFIESCHECK (1<<2) /* do jiffies check */
127
128 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
129
130 #define xrun_debug(substream, mask) \
131 ((substream)->pstr->xrun_debug & (mask))
132 #else
133 #define xrun_debug(substream, mask) 0
134 #endif
135
136 #define dump_stack_on_xrun(substream) do { \
137 if (xrun_debug(substream, XRUN_DEBUG_STACK)) \
138 dump_stack(); \
139 } while (0)
140
141 /* call with stream lock held */
__snd_pcm_xrun(struct snd_pcm_substream * substream)142 void __snd_pcm_xrun(struct snd_pcm_substream *substream)
143 {
144 struct snd_pcm_runtime *runtime = substream->runtime;
145
146 trace_xrun(substream);
147 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
148 struct timespec64 tstamp;
149
150 snd_pcm_gettime(runtime, &tstamp);
151 runtime->status->tstamp.tv_sec = tstamp.tv_sec;
152 runtime->status->tstamp.tv_nsec = tstamp.tv_nsec;
153 }
154 snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
155 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
156 char name[16];
157 snd_pcm_debug_name(substream, name, sizeof(name));
158 pcm_warn(substream->pcm, "XRUN: %s\n", name);
159 dump_stack_on_xrun(substream);
160 }
161 }
162
163 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
164 #define hw_ptr_error(substream, in_interrupt, reason, fmt, args...) \
165 do { \
166 trace_hw_ptr_error(substream, reason); \
167 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) { \
168 pr_err_ratelimited("ALSA: PCM: [%c] " reason ": " fmt, \
169 (in_interrupt) ? 'Q' : 'P', ##args); \
170 dump_stack_on_xrun(substream); \
171 } \
172 } while (0)
173
174 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
175
176 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
177
178 #endif
179
snd_pcm_update_state(struct snd_pcm_substream * substream,struct snd_pcm_runtime * runtime)180 int snd_pcm_update_state(struct snd_pcm_substream *substream,
181 struct snd_pcm_runtime *runtime)
182 {
183 snd_pcm_uframes_t avail;
184
185 avail = snd_pcm_avail(substream);
186 if (avail > runtime->avail_max)
187 runtime->avail_max = avail;
188 if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
189 if (avail >= runtime->buffer_size) {
190 snd_pcm_drain_done(substream);
191 return -EPIPE;
192 }
193 } else {
194 if (avail >= runtime->stop_threshold) {
195 __snd_pcm_xrun(substream);
196 return -EPIPE;
197 }
198 }
199 if (runtime->twake) {
200 if (avail >= runtime->twake)
201 wake_up(&runtime->tsleep);
202 } else if (avail >= runtime->control->avail_min)
203 wake_up(&runtime->sleep);
204 return 0;
205 }
206
update_audio_tstamp(struct snd_pcm_substream * substream,struct timespec64 * curr_tstamp,struct timespec64 * audio_tstamp)207 static void update_audio_tstamp(struct snd_pcm_substream *substream,
208 struct timespec64 *curr_tstamp,
209 struct timespec64 *audio_tstamp)
210 {
211 struct snd_pcm_runtime *runtime = substream->runtime;
212 u64 audio_frames, audio_nsecs;
213 struct timespec64 driver_tstamp;
214
215 if (runtime->tstamp_mode != SNDRV_PCM_TSTAMP_ENABLE)
216 return;
217
218 if (!(substream->ops->get_time_info) ||
219 (runtime->audio_tstamp_report.actual_type ==
220 SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
221
222 /*
223 * provide audio timestamp derived from pointer position
224 * add delay only if requested
225 */
226
227 audio_frames = runtime->hw_ptr_wrap + runtime->status->hw_ptr;
228
229 if (runtime->audio_tstamp_config.report_delay) {
230 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
231 audio_frames -= runtime->delay;
232 else
233 audio_frames += runtime->delay;
234 }
235 audio_nsecs = div_u64(audio_frames * 1000000000LL,
236 runtime->rate);
237 *audio_tstamp = ns_to_timespec64(audio_nsecs);
238 }
239
240 if (runtime->status->audio_tstamp.tv_sec != audio_tstamp->tv_sec ||
241 runtime->status->audio_tstamp.tv_nsec != audio_tstamp->tv_nsec) {
242 runtime->status->audio_tstamp.tv_sec = audio_tstamp->tv_sec;
243 runtime->status->audio_tstamp.tv_nsec = audio_tstamp->tv_nsec;
244 runtime->status->tstamp.tv_sec = curr_tstamp->tv_sec;
245 runtime->status->tstamp.tv_nsec = curr_tstamp->tv_nsec;
246 }
247
248
249 /*
250 * re-take a driver timestamp to let apps detect if the reference tstamp
251 * read by low-level hardware was provided with a delay
252 */
253 snd_pcm_gettime(substream->runtime, &driver_tstamp);
254 runtime->driver_tstamp = driver_tstamp;
255 }
256
snd_pcm_update_hw_ptr0(struct snd_pcm_substream * substream,unsigned int in_interrupt)257 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
258 unsigned int in_interrupt)
259 {
260 struct snd_pcm_runtime *runtime = substream->runtime;
261 snd_pcm_uframes_t pos;
262 snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
263 snd_pcm_sframes_t hdelta, delta;
264 unsigned long jdelta;
265 unsigned long curr_jiffies;
266 struct timespec64 curr_tstamp;
267 struct timespec64 audio_tstamp;
268 int crossed_boundary = 0;
269
270 old_hw_ptr = runtime->status->hw_ptr;
271
272 /*
273 * group pointer, time and jiffies reads to allow for more
274 * accurate correlations/corrections.
275 * The values are stored at the end of this routine after
276 * corrections for hw_ptr position
277 */
278 pos = substream->ops->pointer(substream);
279 curr_jiffies = jiffies;
280 if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
281 if ((substream->ops->get_time_info) &&
282 (runtime->audio_tstamp_config.type_requested != SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
283 substream->ops->get_time_info(substream, &curr_tstamp,
284 &audio_tstamp,
285 &runtime->audio_tstamp_config,
286 &runtime->audio_tstamp_report);
287
288 /* re-test in case tstamp type is not supported in hardware and was demoted to DEFAULT */
289 if (runtime->audio_tstamp_report.actual_type == SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)
290 snd_pcm_gettime(runtime, &curr_tstamp);
291 } else
292 snd_pcm_gettime(runtime, &curr_tstamp);
293 }
294
295 if (pos == SNDRV_PCM_POS_XRUN) {
296 __snd_pcm_xrun(substream);
297 return -EPIPE;
298 }
299 if (pos >= runtime->buffer_size) {
300 if (printk_ratelimit()) {
301 char name[16];
302 snd_pcm_debug_name(substream, name, sizeof(name));
303 pcm_err(substream->pcm,
304 "invalid position: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
305 name, pos, runtime->buffer_size,
306 runtime->period_size);
307 }
308 pos = 0;
309 }
310 pos -= pos % runtime->min_align;
311 trace_hwptr(substream, pos, in_interrupt);
312 hw_base = runtime->hw_ptr_base;
313 new_hw_ptr = hw_base + pos;
314 if (in_interrupt) {
315 /* we know that one period was processed */
316 /* delta = "expected next hw_ptr" for in_interrupt != 0 */
317 delta = runtime->hw_ptr_interrupt + runtime->period_size;
318 if (delta > new_hw_ptr) {
319 /* check for double acknowledged interrupts */
320 hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
321 if (hdelta > runtime->hw_ptr_buffer_jiffies/2 + 1) {
322 hw_base += runtime->buffer_size;
323 if (hw_base >= runtime->boundary) {
324 hw_base = 0;
325 crossed_boundary++;
326 }
327 new_hw_ptr = hw_base + pos;
328 goto __delta;
329 }
330 }
331 }
332 /* new_hw_ptr might be lower than old_hw_ptr in case when */
333 /* pointer crosses the end of the ring buffer */
334 if (new_hw_ptr < old_hw_ptr) {
335 hw_base += runtime->buffer_size;
336 if (hw_base >= runtime->boundary) {
337 hw_base = 0;
338 crossed_boundary++;
339 }
340 new_hw_ptr = hw_base + pos;
341 }
342 __delta:
343 delta = new_hw_ptr - old_hw_ptr;
344 if (delta < 0)
345 delta += runtime->boundary;
346
347 if (runtime->no_period_wakeup) {
348 snd_pcm_sframes_t xrun_threshold;
349 /*
350 * Without regular period interrupts, we have to check
351 * the elapsed time to detect xruns.
352 */
353 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
354 if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
355 goto no_delta_check;
356 hdelta = jdelta - delta * HZ / runtime->rate;
357 xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
358 while (hdelta > xrun_threshold) {
359 delta += runtime->buffer_size;
360 hw_base += runtime->buffer_size;
361 if (hw_base >= runtime->boundary) {
362 hw_base = 0;
363 crossed_boundary++;
364 }
365 new_hw_ptr = hw_base + pos;
366 hdelta -= runtime->hw_ptr_buffer_jiffies;
367 }
368 goto no_delta_check;
369 }
370
371 /* something must be really wrong */
372 if (delta >= runtime->buffer_size + runtime->period_size) {
373 hw_ptr_error(substream, in_interrupt, "Unexpected hw_ptr",
374 "(stream=%i, pos=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
375 substream->stream, (long)pos,
376 (long)new_hw_ptr, (long)old_hw_ptr);
377 return 0;
378 }
379
380 /* Do jiffies check only in xrun_debug mode */
381 if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
382 goto no_jiffies_check;
383
384 /* Skip the jiffies check for hardwares with BATCH flag.
385 * Such hardware usually just increases the position at each IRQ,
386 * thus it can't give any strange position.
387 */
388 if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
389 goto no_jiffies_check;
390 hdelta = delta;
391 if (hdelta < runtime->delay)
392 goto no_jiffies_check;
393 hdelta -= runtime->delay;
394 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
395 if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
396 delta = jdelta /
397 (((runtime->period_size * HZ) / runtime->rate)
398 + HZ/100);
399 /* move new_hw_ptr according jiffies not pos variable */
400 new_hw_ptr = old_hw_ptr;
401 hw_base = delta;
402 /* use loop to avoid checks for delta overflows */
403 /* the delta value is small or zero in most cases */
404 while (delta > 0) {
405 new_hw_ptr += runtime->period_size;
406 if (new_hw_ptr >= runtime->boundary) {
407 new_hw_ptr -= runtime->boundary;
408 crossed_boundary--;
409 }
410 delta--;
411 }
412 /* align hw_base to buffer_size */
413 hw_ptr_error(substream, in_interrupt, "hw_ptr skipping",
414 "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
415 (long)pos, (long)hdelta,
416 (long)runtime->period_size, jdelta,
417 ((hdelta * HZ) / runtime->rate), hw_base,
418 (unsigned long)old_hw_ptr,
419 (unsigned long)new_hw_ptr);
420 /* reset values to proper state */
421 delta = 0;
422 hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
423 }
424 no_jiffies_check:
425 if (delta > runtime->period_size + runtime->period_size / 2) {
426 hw_ptr_error(substream, in_interrupt,
427 "Lost interrupts?",
428 "(stream=%i, delta=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
429 substream->stream, (long)delta,
430 (long)new_hw_ptr,
431 (long)old_hw_ptr);
432 }
433
434 no_delta_check:
435 if (runtime->status->hw_ptr == new_hw_ptr) {
436 runtime->hw_ptr_jiffies = curr_jiffies;
437 update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
438 return 0;
439 }
440
441 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
442 runtime->silence_size > 0)
443 snd_pcm_playback_silence(substream, new_hw_ptr);
444
445 if (in_interrupt) {
446 delta = new_hw_ptr - runtime->hw_ptr_interrupt;
447 if (delta < 0)
448 delta += runtime->boundary;
449 delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
450 runtime->hw_ptr_interrupt += delta;
451 if (runtime->hw_ptr_interrupt >= runtime->boundary)
452 runtime->hw_ptr_interrupt -= runtime->boundary;
453 }
454 runtime->hw_ptr_base = hw_base;
455 runtime->status->hw_ptr = new_hw_ptr;
456 runtime->hw_ptr_jiffies = curr_jiffies;
457 if (crossed_boundary) {
458 snd_BUG_ON(crossed_boundary != 1);
459 runtime->hw_ptr_wrap += runtime->boundary;
460 }
461
462 update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
463
464 return snd_pcm_update_state(substream, runtime);
465 }
466
467 /* CAUTION: call it with irq disabled */
snd_pcm_update_hw_ptr(struct snd_pcm_substream * substream)468 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
469 {
470 return snd_pcm_update_hw_ptr0(substream, 0);
471 }
472
473 /**
474 * snd_pcm_set_ops - set the PCM operators
475 * @pcm: the pcm instance
476 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
477 * @ops: the operator table
478 *
479 * Sets the given PCM operators to the pcm instance.
480 */
snd_pcm_set_ops(struct snd_pcm * pcm,int direction,const struct snd_pcm_ops * ops)481 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
482 const struct snd_pcm_ops *ops)
483 {
484 struct snd_pcm_str *stream = &pcm->streams[direction];
485 struct snd_pcm_substream *substream;
486
487 for (substream = stream->substream; substream != NULL; substream = substream->next)
488 substream->ops = ops;
489 }
490 EXPORT_SYMBOL(snd_pcm_set_ops);
491
492 /**
493 * snd_pcm_set_sync - set the PCM sync id
494 * @substream: the pcm substream
495 *
496 * Sets the PCM sync identifier for the card.
497 */
snd_pcm_set_sync(struct snd_pcm_substream * substream)498 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
499 {
500 struct snd_pcm_runtime *runtime = substream->runtime;
501
502 runtime->sync.id32[0] = substream->pcm->card->number;
503 runtime->sync.id32[1] = -1;
504 runtime->sync.id32[2] = -1;
505 runtime->sync.id32[3] = -1;
506 }
507 EXPORT_SYMBOL(snd_pcm_set_sync);
508
509 /*
510 * Standard ioctl routine
511 */
512
div32(unsigned int a,unsigned int b,unsigned int * r)513 static inline unsigned int div32(unsigned int a, unsigned int b,
514 unsigned int *r)
515 {
516 if (b == 0) {
517 *r = 0;
518 return UINT_MAX;
519 }
520 *r = a % b;
521 return a / b;
522 }
523
div_down(unsigned int a,unsigned int b)524 static inline unsigned int div_down(unsigned int a, unsigned int b)
525 {
526 if (b == 0)
527 return UINT_MAX;
528 return a / b;
529 }
530
div_up(unsigned int a,unsigned int b)531 static inline unsigned int div_up(unsigned int a, unsigned int b)
532 {
533 unsigned int r;
534 unsigned int q;
535 if (b == 0)
536 return UINT_MAX;
537 q = div32(a, b, &r);
538 if (r)
539 ++q;
540 return q;
541 }
542
mul(unsigned int a,unsigned int b)543 static inline unsigned int mul(unsigned int a, unsigned int b)
544 {
545 if (a == 0)
546 return 0;
547 if (div_down(UINT_MAX, a) < b)
548 return UINT_MAX;
549 return a * b;
550 }
551
muldiv32(unsigned int a,unsigned int b,unsigned int c,unsigned int * r)552 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
553 unsigned int c, unsigned int *r)
554 {
555 u_int64_t n = (u_int64_t) a * b;
556 if (c == 0) {
557 *r = 0;
558 return UINT_MAX;
559 }
560 n = div_u64_rem(n, c, r);
561 if (n >= UINT_MAX) {
562 *r = 0;
563 return UINT_MAX;
564 }
565 return n;
566 }
567
568 /**
569 * snd_interval_refine - refine the interval value of configurator
570 * @i: the interval value to refine
571 * @v: the interval value to refer to
572 *
573 * Refines the interval value with the reference value.
574 * The interval is changed to the range satisfying both intervals.
575 * The interval status (min, max, integer, etc.) are evaluated.
576 *
577 * Return: Positive if the value is changed, zero if it's not changed, or a
578 * negative error code.
579 */
snd_interval_refine(struct snd_interval * i,const struct snd_interval * v)580 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
581 {
582 int changed = 0;
583 if (snd_BUG_ON(snd_interval_empty(i)))
584 return -EINVAL;
585 if (i->min < v->min) {
586 i->min = v->min;
587 i->openmin = v->openmin;
588 changed = 1;
589 } else if (i->min == v->min && !i->openmin && v->openmin) {
590 i->openmin = 1;
591 changed = 1;
592 }
593 if (i->max > v->max) {
594 i->max = v->max;
595 i->openmax = v->openmax;
596 changed = 1;
597 } else if (i->max == v->max && !i->openmax && v->openmax) {
598 i->openmax = 1;
599 changed = 1;
600 }
601 if (!i->integer && v->integer) {
602 i->integer = 1;
603 changed = 1;
604 }
605 if (i->integer) {
606 if (i->openmin) {
607 i->min++;
608 i->openmin = 0;
609 }
610 if (i->openmax) {
611 i->max--;
612 i->openmax = 0;
613 }
614 } else if (!i->openmin && !i->openmax && i->min == i->max)
615 i->integer = 1;
616 if (snd_interval_checkempty(i)) {
617 snd_interval_none(i);
618 return -EINVAL;
619 }
620 return changed;
621 }
622 EXPORT_SYMBOL(snd_interval_refine);
623
snd_interval_refine_first(struct snd_interval * i)624 static int snd_interval_refine_first(struct snd_interval *i)
625 {
626 const unsigned int last_max = i->max;
627
628 if (snd_BUG_ON(snd_interval_empty(i)))
629 return -EINVAL;
630 if (snd_interval_single(i))
631 return 0;
632 i->max = i->min;
633 if (i->openmin)
634 i->max++;
635 /* only exclude max value if also excluded before refine */
636 i->openmax = (i->openmax && i->max >= last_max);
637 return 1;
638 }
639
snd_interval_refine_last(struct snd_interval * i)640 static int snd_interval_refine_last(struct snd_interval *i)
641 {
642 const unsigned int last_min = i->min;
643
644 if (snd_BUG_ON(snd_interval_empty(i)))
645 return -EINVAL;
646 if (snd_interval_single(i))
647 return 0;
648 i->min = i->max;
649 if (i->openmax)
650 i->min--;
651 /* only exclude min value if also excluded before refine */
652 i->openmin = (i->openmin && i->min <= last_min);
653 return 1;
654 }
655
snd_interval_mul(const struct snd_interval * a,const struct snd_interval * b,struct snd_interval * c)656 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
657 {
658 if (a->empty || b->empty) {
659 snd_interval_none(c);
660 return;
661 }
662 c->empty = 0;
663 c->min = mul(a->min, b->min);
664 c->openmin = (a->openmin || b->openmin);
665 c->max = mul(a->max, b->max);
666 c->openmax = (a->openmax || b->openmax);
667 c->integer = (a->integer && b->integer);
668 }
669
670 /**
671 * snd_interval_div - refine the interval value with division
672 * @a: dividend
673 * @b: divisor
674 * @c: quotient
675 *
676 * c = a / b
677 *
678 * Returns non-zero if the value is changed, zero if not changed.
679 */
snd_interval_div(const struct snd_interval * a,const struct snd_interval * b,struct snd_interval * c)680 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
681 {
682 unsigned int r;
683 if (a->empty || b->empty) {
684 snd_interval_none(c);
685 return;
686 }
687 c->empty = 0;
688 c->min = div32(a->min, b->max, &r);
689 c->openmin = (r || a->openmin || b->openmax);
690 if (b->min > 0) {
691 c->max = div32(a->max, b->min, &r);
692 if (r) {
693 c->max++;
694 c->openmax = 1;
695 } else
696 c->openmax = (a->openmax || b->openmin);
697 } else {
698 c->max = UINT_MAX;
699 c->openmax = 0;
700 }
701 c->integer = 0;
702 }
703
704 /**
705 * snd_interval_muldivk - refine the interval value
706 * @a: dividend 1
707 * @b: dividend 2
708 * @k: divisor (as integer)
709 * @c: result
710 *
711 * c = a * b / k
712 *
713 * Returns non-zero if the value is changed, zero if not changed.
714 */
snd_interval_muldivk(const struct snd_interval * a,const struct snd_interval * b,unsigned int k,struct snd_interval * c)715 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
716 unsigned int k, struct snd_interval *c)
717 {
718 unsigned int r;
719 if (a->empty || b->empty) {
720 snd_interval_none(c);
721 return;
722 }
723 c->empty = 0;
724 c->min = muldiv32(a->min, b->min, k, &r);
725 c->openmin = (r || a->openmin || b->openmin);
726 c->max = muldiv32(a->max, b->max, k, &r);
727 if (r) {
728 c->max++;
729 c->openmax = 1;
730 } else
731 c->openmax = (a->openmax || b->openmax);
732 c->integer = 0;
733 }
734
735 /**
736 * snd_interval_mulkdiv - refine the interval value
737 * @a: dividend 1
738 * @k: dividend 2 (as integer)
739 * @b: divisor
740 * @c: result
741 *
742 * c = a * k / b
743 *
744 * Returns non-zero if the value is changed, zero if not changed.
745 */
snd_interval_mulkdiv(const struct snd_interval * a,unsigned int k,const struct snd_interval * b,struct snd_interval * c)746 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
747 const struct snd_interval *b, struct snd_interval *c)
748 {
749 unsigned int r;
750 if (a->empty || b->empty) {
751 snd_interval_none(c);
752 return;
753 }
754 c->empty = 0;
755 c->min = muldiv32(a->min, k, b->max, &r);
756 c->openmin = (r || a->openmin || b->openmax);
757 if (b->min > 0) {
758 c->max = muldiv32(a->max, k, b->min, &r);
759 if (r) {
760 c->max++;
761 c->openmax = 1;
762 } else
763 c->openmax = (a->openmax || b->openmin);
764 } else {
765 c->max = UINT_MAX;
766 c->openmax = 0;
767 }
768 c->integer = 0;
769 }
770
771 /* ---- */
772
773
774 /**
775 * snd_interval_ratnum - refine the interval value
776 * @i: interval to refine
777 * @rats_count: number of ratnum_t
778 * @rats: ratnum_t array
779 * @nump: pointer to store the resultant numerator
780 * @denp: pointer to store the resultant denominator
781 *
782 * Return: Positive if the value is changed, zero if it's not changed, or a
783 * negative error code.
784 */
snd_interval_ratnum(struct snd_interval * i,unsigned int rats_count,const struct snd_ratnum * rats,unsigned int * nump,unsigned int * denp)785 int snd_interval_ratnum(struct snd_interval *i,
786 unsigned int rats_count, const struct snd_ratnum *rats,
787 unsigned int *nump, unsigned int *denp)
788 {
789 unsigned int best_num, best_den;
790 int best_diff;
791 unsigned int k;
792 struct snd_interval t;
793 int err;
794 unsigned int result_num, result_den;
795 int result_diff;
796
797 best_num = best_den = best_diff = 0;
798 for (k = 0; k < rats_count; ++k) {
799 unsigned int num = rats[k].num;
800 unsigned int den;
801 unsigned int q = i->min;
802 int diff;
803 if (q == 0)
804 q = 1;
805 den = div_up(num, q);
806 if (den < rats[k].den_min)
807 continue;
808 if (den > rats[k].den_max)
809 den = rats[k].den_max;
810 else {
811 unsigned int r;
812 r = (den - rats[k].den_min) % rats[k].den_step;
813 if (r != 0)
814 den -= r;
815 }
816 diff = num - q * den;
817 if (diff < 0)
818 diff = -diff;
819 if (best_num == 0 ||
820 diff * best_den < best_diff * den) {
821 best_diff = diff;
822 best_den = den;
823 best_num = num;
824 }
825 }
826 if (best_den == 0) {
827 i->empty = 1;
828 return -EINVAL;
829 }
830 t.min = div_down(best_num, best_den);
831 t.openmin = !!(best_num % best_den);
832
833 result_num = best_num;
834 result_diff = best_diff;
835 result_den = best_den;
836 best_num = best_den = best_diff = 0;
837 for (k = 0; k < rats_count; ++k) {
838 unsigned int num = rats[k].num;
839 unsigned int den;
840 unsigned int q = i->max;
841 int diff;
842 if (q == 0) {
843 i->empty = 1;
844 return -EINVAL;
845 }
846 den = div_down(num, q);
847 if (den > rats[k].den_max)
848 continue;
849 if (den < rats[k].den_min)
850 den = rats[k].den_min;
851 else {
852 unsigned int r;
853 r = (den - rats[k].den_min) % rats[k].den_step;
854 if (r != 0)
855 den += rats[k].den_step - r;
856 }
857 diff = q * den - num;
858 if (diff < 0)
859 diff = -diff;
860 if (best_num == 0 ||
861 diff * best_den < best_diff * den) {
862 best_diff = diff;
863 best_den = den;
864 best_num = num;
865 }
866 }
867 if (best_den == 0) {
868 i->empty = 1;
869 return -EINVAL;
870 }
871 t.max = div_up(best_num, best_den);
872 t.openmax = !!(best_num % best_den);
873 t.integer = 0;
874 err = snd_interval_refine(i, &t);
875 if (err < 0)
876 return err;
877
878 if (snd_interval_single(i)) {
879 if (best_diff * result_den < result_diff * best_den) {
880 result_num = best_num;
881 result_den = best_den;
882 }
883 if (nump)
884 *nump = result_num;
885 if (denp)
886 *denp = result_den;
887 }
888 return err;
889 }
890 EXPORT_SYMBOL(snd_interval_ratnum);
891
892 /**
893 * snd_interval_ratden - refine the interval value
894 * @i: interval to refine
895 * @rats_count: number of struct ratden
896 * @rats: struct ratden array
897 * @nump: pointer to store the resultant numerator
898 * @denp: pointer to store the resultant denominator
899 *
900 * Return: Positive if the value is changed, zero if it's not changed, or a
901 * negative error code.
902 */
snd_interval_ratden(struct snd_interval * i,unsigned int rats_count,const struct snd_ratden * rats,unsigned int * nump,unsigned int * denp)903 static int snd_interval_ratden(struct snd_interval *i,
904 unsigned int rats_count,
905 const struct snd_ratden *rats,
906 unsigned int *nump, unsigned int *denp)
907 {
908 unsigned int best_num, best_diff, best_den;
909 unsigned int k;
910 struct snd_interval t;
911 int err;
912
913 best_num = best_den = best_diff = 0;
914 for (k = 0; k < rats_count; ++k) {
915 unsigned int num;
916 unsigned int den = rats[k].den;
917 unsigned int q = i->min;
918 int diff;
919 num = mul(q, den);
920 if (num > rats[k].num_max)
921 continue;
922 if (num < rats[k].num_min)
923 num = rats[k].num_max;
924 else {
925 unsigned int r;
926 r = (num - rats[k].num_min) % rats[k].num_step;
927 if (r != 0)
928 num += rats[k].num_step - r;
929 }
930 diff = num - q * den;
931 if (best_num == 0 ||
932 diff * best_den < best_diff * den) {
933 best_diff = diff;
934 best_den = den;
935 best_num = num;
936 }
937 }
938 if (best_den == 0) {
939 i->empty = 1;
940 return -EINVAL;
941 }
942 t.min = div_down(best_num, best_den);
943 t.openmin = !!(best_num % best_den);
944
945 best_num = best_den = best_diff = 0;
946 for (k = 0; k < rats_count; ++k) {
947 unsigned int num;
948 unsigned int den = rats[k].den;
949 unsigned int q = i->max;
950 int diff;
951 num = mul(q, den);
952 if (num < rats[k].num_min)
953 continue;
954 if (num > rats[k].num_max)
955 num = rats[k].num_max;
956 else {
957 unsigned int r;
958 r = (num - rats[k].num_min) % rats[k].num_step;
959 if (r != 0)
960 num -= r;
961 }
962 diff = q * den - num;
963 if (best_num == 0 ||
964 diff * best_den < best_diff * den) {
965 best_diff = diff;
966 best_den = den;
967 best_num = num;
968 }
969 }
970 if (best_den == 0) {
971 i->empty = 1;
972 return -EINVAL;
973 }
974 t.max = div_up(best_num, best_den);
975 t.openmax = !!(best_num % best_den);
976 t.integer = 0;
977 err = snd_interval_refine(i, &t);
978 if (err < 0)
979 return err;
980
981 if (snd_interval_single(i)) {
982 if (nump)
983 *nump = best_num;
984 if (denp)
985 *denp = best_den;
986 }
987 return err;
988 }
989
990 /**
991 * snd_interval_list - refine the interval value from the list
992 * @i: the interval value to refine
993 * @count: the number of elements in the list
994 * @list: the value list
995 * @mask: the bit-mask to evaluate
996 *
997 * Refines the interval value from the list.
998 * When mask is non-zero, only the elements corresponding to bit 1 are
999 * evaluated.
1000 *
1001 * Return: Positive if the value is changed, zero if it's not changed, or a
1002 * negative error code.
1003 */
snd_interval_list(struct snd_interval * i,unsigned int count,const unsigned int * list,unsigned int mask)1004 int snd_interval_list(struct snd_interval *i, unsigned int count,
1005 const unsigned int *list, unsigned int mask)
1006 {
1007 unsigned int k;
1008 struct snd_interval list_range;
1009
1010 if (!count) {
1011 i->empty = 1;
1012 return -EINVAL;
1013 }
1014 snd_interval_any(&list_range);
1015 list_range.min = UINT_MAX;
1016 list_range.max = 0;
1017 for (k = 0; k < count; k++) {
1018 if (mask && !(mask & (1 << k)))
1019 continue;
1020 if (!snd_interval_test(i, list[k]))
1021 continue;
1022 list_range.min = min(list_range.min, list[k]);
1023 list_range.max = max(list_range.max, list[k]);
1024 }
1025 return snd_interval_refine(i, &list_range);
1026 }
1027 EXPORT_SYMBOL(snd_interval_list);
1028
1029 /**
1030 * snd_interval_ranges - refine the interval value from the list of ranges
1031 * @i: the interval value to refine
1032 * @count: the number of elements in the list of ranges
1033 * @ranges: the ranges list
1034 * @mask: the bit-mask to evaluate
1035 *
1036 * Refines the interval value from the list of ranges.
1037 * When mask is non-zero, only the elements corresponding to bit 1 are
1038 * evaluated.
1039 *
1040 * Return: Positive if the value is changed, zero if it's not changed, or a
1041 * negative error code.
1042 */
snd_interval_ranges(struct snd_interval * i,unsigned int count,const struct snd_interval * ranges,unsigned int mask)1043 int snd_interval_ranges(struct snd_interval *i, unsigned int count,
1044 const struct snd_interval *ranges, unsigned int mask)
1045 {
1046 unsigned int k;
1047 struct snd_interval range_union;
1048 struct snd_interval range;
1049
1050 if (!count) {
1051 snd_interval_none(i);
1052 return -EINVAL;
1053 }
1054 snd_interval_any(&range_union);
1055 range_union.min = UINT_MAX;
1056 range_union.max = 0;
1057 for (k = 0; k < count; k++) {
1058 if (mask && !(mask & (1 << k)))
1059 continue;
1060 snd_interval_copy(&range, &ranges[k]);
1061 if (snd_interval_refine(&range, i) < 0)
1062 continue;
1063 if (snd_interval_empty(&range))
1064 continue;
1065
1066 if (range.min < range_union.min) {
1067 range_union.min = range.min;
1068 range_union.openmin = 1;
1069 }
1070 if (range.min == range_union.min && !range.openmin)
1071 range_union.openmin = 0;
1072 if (range.max > range_union.max) {
1073 range_union.max = range.max;
1074 range_union.openmax = 1;
1075 }
1076 if (range.max == range_union.max && !range.openmax)
1077 range_union.openmax = 0;
1078 }
1079 return snd_interval_refine(i, &range_union);
1080 }
1081 EXPORT_SYMBOL(snd_interval_ranges);
1082
snd_interval_step(struct snd_interval * i,unsigned int step)1083 static int snd_interval_step(struct snd_interval *i, unsigned int step)
1084 {
1085 unsigned int n;
1086 int changed = 0;
1087 n = i->min % step;
1088 if (n != 0 || i->openmin) {
1089 i->min += step - n;
1090 i->openmin = 0;
1091 changed = 1;
1092 }
1093 n = i->max % step;
1094 if (n != 0 || i->openmax) {
1095 i->max -= n;
1096 i->openmax = 0;
1097 changed = 1;
1098 }
1099 if (snd_interval_checkempty(i)) {
1100 i->empty = 1;
1101 return -EINVAL;
1102 }
1103 return changed;
1104 }
1105
1106 /* Info constraints helpers */
1107
1108 /**
1109 * snd_pcm_hw_rule_add - add the hw-constraint rule
1110 * @runtime: the pcm runtime instance
1111 * @cond: condition bits
1112 * @var: the variable to evaluate
1113 * @func: the evaluation function
1114 * @private: the private data pointer passed to function
1115 * @dep: the dependent variables
1116 *
1117 * Return: Zero if successful, or a negative error code on failure.
1118 */
snd_pcm_hw_rule_add(struct snd_pcm_runtime * runtime,unsigned int cond,int var,snd_pcm_hw_rule_func_t func,void * private,int dep,...)1119 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1120 int var,
1121 snd_pcm_hw_rule_func_t func, void *private,
1122 int dep, ...)
1123 {
1124 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1125 struct snd_pcm_hw_rule *c;
1126 unsigned int k;
1127 va_list args;
1128 va_start(args, dep);
1129 if (constrs->rules_num >= constrs->rules_all) {
1130 struct snd_pcm_hw_rule *new;
1131 unsigned int new_rules = constrs->rules_all + 16;
1132 new = krealloc_array(constrs->rules, new_rules,
1133 sizeof(*c), GFP_KERNEL);
1134 if (!new) {
1135 va_end(args);
1136 return -ENOMEM;
1137 }
1138 constrs->rules = new;
1139 constrs->rules_all = new_rules;
1140 }
1141 c = &constrs->rules[constrs->rules_num];
1142 c->cond = cond;
1143 c->func = func;
1144 c->var = var;
1145 c->private = private;
1146 k = 0;
1147 while (1) {
1148 if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1149 va_end(args);
1150 return -EINVAL;
1151 }
1152 c->deps[k++] = dep;
1153 if (dep < 0)
1154 break;
1155 dep = va_arg(args, int);
1156 }
1157 constrs->rules_num++;
1158 va_end(args);
1159 return 0;
1160 }
1161 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1162
1163 /**
1164 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1165 * @runtime: PCM runtime instance
1166 * @var: hw_params variable to apply the mask
1167 * @mask: the bitmap mask
1168 *
1169 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1170 *
1171 * Return: Zero if successful, or a negative error code on failure.
1172 */
snd_pcm_hw_constraint_mask(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var,u_int32_t mask)1173 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1174 u_int32_t mask)
1175 {
1176 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1177 struct snd_mask *maskp = constrs_mask(constrs, var);
1178 *maskp->bits &= mask;
1179 memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1180 if (*maskp->bits == 0)
1181 return -EINVAL;
1182 return 0;
1183 }
1184
1185 /**
1186 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1187 * @runtime: PCM runtime instance
1188 * @var: hw_params variable to apply the mask
1189 * @mask: the 64bit bitmap mask
1190 *
1191 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1192 *
1193 * Return: Zero if successful, or a negative error code on failure.
1194 */
snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var,u_int64_t mask)1195 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1196 u_int64_t mask)
1197 {
1198 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1199 struct snd_mask *maskp = constrs_mask(constrs, var);
1200 maskp->bits[0] &= (u_int32_t)mask;
1201 maskp->bits[1] &= (u_int32_t)(mask >> 32);
1202 memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1203 if (! maskp->bits[0] && ! maskp->bits[1])
1204 return -EINVAL;
1205 return 0;
1206 }
1207 EXPORT_SYMBOL(snd_pcm_hw_constraint_mask64);
1208
1209 /**
1210 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1211 * @runtime: PCM runtime instance
1212 * @var: hw_params variable to apply the integer constraint
1213 *
1214 * Apply the constraint of integer to an interval parameter.
1215 *
1216 * Return: Positive if the value is changed, zero if it's not changed, or a
1217 * negative error code.
1218 */
snd_pcm_hw_constraint_integer(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var)1219 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1220 {
1221 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1222 return snd_interval_setinteger(constrs_interval(constrs, var));
1223 }
1224 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1225
1226 /**
1227 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1228 * @runtime: PCM runtime instance
1229 * @var: hw_params variable to apply the range
1230 * @min: the minimal value
1231 * @max: the maximal value
1232 *
1233 * Apply the min/max range constraint to an interval parameter.
1234 *
1235 * Return: Positive if the value is changed, zero if it's not changed, or a
1236 * negative error code.
1237 */
snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var,unsigned int min,unsigned int max)1238 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1239 unsigned int min, unsigned int max)
1240 {
1241 struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1242 struct snd_interval t;
1243 t.min = min;
1244 t.max = max;
1245 t.openmin = t.openmax = 0;
1246 t.integer = 0;
1247 return snd_interval_refine(constrs_interval(constrs, var), &t);
1248 }
1249 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1250
snd_pcm_hw_rule_list(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1251 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1252 struct snd_pcm_hw_rule *rule)
1253 {
1254 struct snd_pcm_hw_constraint_list *list = rule->private;
1255 return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1256 }
1257
1258
1259 /**
1260 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1261 * @runtime: PCM runtime instance
1262 * @cond: condition bits
1263 * @var: hw_params variable to apply the list constraint
1264 * @l: list
1265 *
1266 * Apply the list of constraints to an interval parameter.
1267 *
1268 * Return: Zero if successful, or a negative error code on failure.
1269 */
snd_pcm_hw_constraint_list(struct snd_pcm_runtime * runtime,unsigned int cond,snd_pcm_hw_param_t var,const struct snd_pcm_hw_constraint_list * l)1270 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1271 unsigned int cond,
1272 snd_pcm_hw_param_t var,
1273 const struct snd_pcm_hw_constraint_list *l)
1274 {
1275 return snd_pcm_hw_rule_add(runtime, cond, var,
1276 snd_pcm_hw_rule_list, (void *)l,
1277 var, -1);
1278 }
1279 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1280
snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1281 static int snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params *params,
1282 struct snd_pcm_hw_rule *rule)
1283 {
1284 struct snd_pcm_hw_constraint_ranges *r = rule->private;
1285 return snd_interval_ranges(hw_param_interval(params, rule->var),
1286 r->count, r->ranges, r->mask);
1287 }
1288
1289
1290 /**
1291 * snd_pcm_hw_constraint_ranges - apply list of range constraints to a parameter
1292 * @runtime: PCM runtime instance
1293 * @cond: condition bits
1294 * @var: hw_params variable to apply the list of range constraints
1295 * @r: ranges
1296 *
1297 * Apply the list of range constraints to an interval parameter.
1298 *
1299 * Return: Zero if successful, or a negative error code on failure.
1300 */
snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime * runtime,unsigned int cond,snd_pcm_hw_param_t var,const struct snd_pcm_hw_constraint_ranges * r)1301 int snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime *runtime,
1302 unsigned int cond,
1303 snd_pcm_hw_param_t var,
1304 const struct snd_pcm_hw_constraint_ranges *r)
1305 {
1306 return snd_pcm_hw_rule_add(runtime, cond, var,
1307 snd_pcm_hw_rule_ranges, (void *)r,
1308 var, -1);
1309 }
1310 EXPORT_SYMBOL(snd_pcm_hw_constraint_ranges);
1311
snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1312 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1313 struct snd_pcm_hw_rule *rule)
1314 {
1315 const struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1316 unsigned int num = 0, den = 0;
1317 int err;
1318 err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1319 r->nrats, r->rats, &num, &den);
1320 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1321 params->rate_num = num;
1322 params->rate_den = den;
1323 }
1324 return err;
1325 }
1326
1327 /**
1328 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1329 * @runtime: PCM runtime instance
1330 * @cond: condition bits
1331 * @var: hw_params variable to apply the ratnums constraint
1332 * @r: struct snd_ratnums constriants
1333 *
1334 * Return: Zero if successful, or a negative error code on failure.
1335 */
snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime * runtime,unsigned int cond,snd_pcm_hw_param_t var,const struct snd_pcm_hw_constraint_ratnums * r)1336 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1337 unsigned int cond,
1338 snd_pcm_hw_param_t var,
1339 const struct snd_pcm_hw_constraint_ratnums *r)
1340 {
1341 return snd_pcm_hw_rule_add(runtime, cond, var,
1342 snd_pcm_hw_rule_ratnums, (void *)r,
1343 var, -1);
1344 }
1345 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1346
snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1347 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1348 struct snd_pcm_hw_rule *rule)
1349 {
1350 const struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1351 unsigned int num = 0, den = 0;
1352 int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1353 r->nrats, r->rats, &num, &den);
1354 if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1355 params->rate_num = num;
1356 params->rate_den = den;
1357 }
1358 return err;
1359 }
1360
1361 /**
1362 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1363 * @runtime: PCM runtime instance
1364 * @cond: condition bits
1365 * @var: hw_params variable to apply the ratdens constraint
1366 * @r: struct snd_ratdens constriants
1367 *
1368 * Return: Zero if successful, or a negative error code on failure.
1369 */
snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime * runtime,unsigned int cond,snd_pcm_hw_param_t var,const struct snd_pcm_hw_constraint_ratdens * r)1370 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1371 unsigned int cond,
1372 snd_pcm_hw_param_t var,
1373 const struct snd_pcm_hw_constraint_ratdens *r)
1374 {
1375 return snd_pcm_hw_rule_add(runtime, cond, var,
1376 snd_pcm_hw_rule_ratdens, (void *)r,
1377 var, -1);
1378 }
1379 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1380
snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1381 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1382 struct snd_pcm_hw_rule *rule)
1383 {
1384 unsigned int l = (unsigned long) rule->private;
1385 int width = l & 0xffff;
1386 unsigned int msbits = l >> 16;
1387 const struct snd_interval *i =
1388 hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1389
1390 if (!snd_interval_single(i))
1391 return 0;
1392
1393 if ((snd_interval_value(i) == width) ||
1394 (width == 0 && snd_interval_value(i) > msbits))
1395 params->msbits = min_not_zero(params->msbits, msbits);
1396
1397 return 0;
1398 }
1399
1400 /**
1401 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1402 * @runtime: PCM runtime instance
1403 * @cond: condition bits
1404 * @width: sample bits width
1405 * @msbits: msbits width
1406 *
1407 * This constraint will set the number of most significant bits (msbits) if a
1408 * sample format with the specified width has been select. If width is set to 0
1409 * the msbits will be set for any sample format with a width larger than the
1410 * specified msbits.
1411 *
1412 * Return: Zero if successful, or a negative error code on failure.
1413 */
snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime * runtime,unsigned int cond,unsigned int width,unsigned int msbits)1414 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1415 unsigned int cond,
1416 unsigned int width,
1417 unsigned int msbits)
1418 {
1419 unsigned long l = (msbits << 16) | width;
1420 return snd_pcm_hw_rule_add(runtime, cond, -1,
1421 snd_pcm_hw_rule_msbits,
1422 (void*) l,
1423 SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1424 }
1425 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1426
snd_pcm_hw_rule_step(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1427 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1428 struct snd_pcm_hw_rule *rule)
1429 {
1430 unsigned long step = (unsigned long) rule->private;
1431 return snd_interval_step(hw_param_interval(params, rule->var), step);
1432 }
1433
1434 /**
1435 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1436 * @runtime: PCM runtime instance
1437 * @cond: condition bits
1438 * @var: hw_params variable to apply the step constraint
1439 * @step: step size
1440 *
1441 * Return: Zero if successful, or a negative error code on failure.
1442 */
snd_pcm_hw_constraint_step(struct snd_pcm_runtime * runtime,unsigned int cond,snd_pcm_hw_param_t var,unsigned long step)1443 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1444 unsigned int cond,
1445 snd_pcm_hw_param_t var,
1446 unsigned long step)
1447 {
1448 return snd_pcm_hw_rule_add(runtime, cond, var,
1449 snd_pcm_hw_rule_step, (void *) step,
1450 var, -1);
1451 }
1452 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1453
snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1454 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1455 {
1456 static const unsigned int pow2_sizes[] = {
1457 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1458 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1459 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1460 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1461 };
1462 return snd_interval_list(hw_param_interval(params, rule->var),
1463 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1464 }
1465
1466 /**
1467 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1468 * @runtime: PCM runtime instance
1469 * @cond: condition bits
1470 * @var: hw_params variable to apply the power-of-2 constraint
1471 *
1472 * Return: Zero if successful, or a negative error code on failure.
1473 */
snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime * runtime,unsigned int cond,snd_pcm_hw_param_t var)1474 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1475 unsigned int cond,
1476 snd_pcm_hw_param_t var)
1477 {
1478 return snd_pcm_hw_rule_add(runtime, cond, var,
1479 snd_pcm_hw_rule_pow2, NULL,
1480 var, -1);
1481 }
1482 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1483
snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1484 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1485 struct snd_pcm_hw_rule *rule)
1486 {
1487 unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1488 struct snd_interval *rate;
1489
1490 rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1491 return snd_interval_list(rate, 1, &base_rate, 0);
1492 }
1493
1494 /**
1495 * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1496 * @runtime: PCM runtime instance
1497 * @base_rate: the rate at which the hardware does not resample
1498 *
1499 * Return: Zero if successful, or a negative error code on failure.
1500 */
snd_pcm_hw_rule_noresample(struct snd_pcm_runtime * runtime,unsigned int base_rate)1501 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1502 unsigned int base_rate)
1503 {
1504 return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1505 SNDRV_PCM_HW_PARAM_RATE,
1506 snd_pcm_hw_rule_noresample_func,
1507 (void *)(uintptr_t)base_rate,
1508 SNDRV_PCM_HW_PARAM_RATE, -1);
1509 }
1510 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1511
_snd_pcm_hw_param_any(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1512 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1513 snd_pcm_hw_param_t var)
1514 {
1515 if (hw_is_mask(var)) {
1516 snd_mask_any(hw_param_mask(params, var));
1517 params->cmask |= 1 << var;
1518 params->rmask |= 1 << var;
1519 return;
1520 }
1521 if (hw_is_interval(var)) {
1522 snd_interval_any(hw_param_interval(params, var));
1523 params->cmask |= 1 << var;
1524 params->rmask |= 1 << var;
1525 return;
1526 }
1527 snd_BUG();
1528 }
1529
_snd_pcm_hw_params_any(struct snd_pcm_hw_params * params)1530 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1531 {
1532 unsigned int k;
1533 memset(params, 0, sizeof(*params));
1534 for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1535 _snd_pcm_hw_param_any(params, k);
1536 for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1537 _snd_pcm_hw_param_any(params, k);
1538 params->info = ~0U;
1539 }
1540 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1541
1542 /**
1543 * snd_pcm_hw_param_value - return @params field @var value
1544 * @params: the hw_params instance
1545 * @var: parameter to retrieve
1546 * @dir: pointer to the direction (-1,0,1) or %NULL
1547 *
1548 * Return: The value for field @var if it's fixed in configuration space
1549 * defined by @params. -%EINVAL otherwise.
1550 */
snd_pcm_hw_param_value(const struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var,int * dir)1551 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1552 snd_pcm_hw_param_t var, int *dir)
1553 {
1554 if (hw_is_mask(var)) {
1555 const struct snd_mask *mask = hw_param_mask_c(params, var);
1556 if (!snd_mask_single(mask))
1557 return -EINVAL;
1558 if (dir)
1559 *dir = 0;
1560 return snd_mask_value(mask);
1561 }
1562 if (hw_is_interval(var)) {
1563 const struct snd_interval *i = hw_param_interval_c(params, var);
1564 if (!snd_interval_single(i))
1565 return -EINVAL;
1566 if (dir)
1567 *dir = i->openmin;
1568 return snd_interval_value(i);
1569 }
1570 return -EINVAL;
1571 }
1572 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1573
_snd_pcm_hw_param_setempty(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1574 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1575 snd_pcm_hw_param_t var)
1576 {
1577 if (hw_is_mask(var)) {
1578 snd_mask_none(hw_param_mask(params, var));
1579 params->cmask |= 1 << var;
1580 params->rmask |= 1 << var;
1581 } else if (hw_is_interval(var)) {
1582 snd_interval_none(hw_param_interval(params, var));
1583 params->cmask |= 1 << var;
1584 params->rmask |= 1 << var;
1585 } else {
1586 snd_BUG();
1587 }
1588 }
1589 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1590
_snd_pcm_hw_param_first(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1591 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1592 snd_pcm_hw_param_t var)
1593 {
1594 int changed;
1595 if (hw_is_mask(var))
1596 changed = snd_mask_refine_first(hw_param_mask(params, var));
1597 else if (hw_is_interval(var))
1598 changed = snd_interval_refine_first(hw_param_interval(params, var));
1599 else
1600 return -EINVAL;
1601 if (changed > 0) {
1602 params->cmask |= 1 << var;
1603 params->rmask |= 1 << var;
1604 }
1605 return changed;
1606 }
1607
1608
1609 /**
1610 * snd_pcm_hw_param_first - refine config space and return minimum value
1611 * @pcm: PCM instance
1612 * @params: the hw_params instance
1613 * @var: parameter to retrieve
1614 * @dir: pointer to the direction (-1,0,1) or %NULL
1615 *
1616 * Inside configuration space defined by @params remove from @var all
1617 * values > minimum. Reduce configuration space accordingly.
1618 *
1619 * Return: The minimum, or a negative error code on failure.
1620 */
snd_pcm_hw_param_first(struct snd_pcm_substream * pcm,struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var,int * dir)1621 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1622 struct snd_pcm_hw_params *params,
1623 snd_pcm_hw_param_t var, int *dir)
1624 {
1625 int changed = _snd_pcm_hw_param_first(params, var);
1626 if (changed < 0)
1627 return changed;
1628 if (params->rmask) {
1629 int err = snd_pcm_hw_refine(pcm, params);
1630 if (err < 0)
1631 return err;
1632 }
1633 return snd_pcm_hw_param_value(params, var, dir);
1634 }
1635 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1636
_snd_pcm_hw_param_last(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1637 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1638 snd_pcm_hw_param_t var)
1639 {
1640 int changed;
1641 if (hw_is_mask(var))
1642 changed = snd_mask_refine_last(hw_param_mask(params, var));
1643 else if (hw_is_interval(var))
1644 changed = snd_interval_refine_last(hw_param_interval(params, var));
1645 else
1646 return -EINVAL;
1647 if (changed > 0) {
1648 params->cmask |= 1 << var;
1649 params->rmask |= 1 << var;
1650 }
1651 return changed;
1652 }
1653
1654
1655 /**
1656 * snd_pcm_hw_param_last - refine config space and return maximum value
1657 * @pcm: PCM instance
1658 * @params: the hw_params instance
1659 * @var: parameter to retrieve
1660 * @dir: pointer to the direction (-1,0,1) or %NULL
1661 *
1662 * Inside configuration space defined by @params remove from @var all
1663 * values < maximum. Reduce configuration space accordingly.
1664 *
1665 * Return: The maximum, or a negative error code on failure.
1666 */
snd_pcm_hw_param_last(struct snd_pcm_substream * pcm,struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var,int * dir)1667 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1668 struct snd_pcm_hw_params *params,
1669 snd_pcm_hw_param_t var, int *dir)
1670 {
1671 int changed = _snd_pcm_hw_param_last(params, var);
1672 if (changed < 0)
1673 return changed;
1674 if (params->rmask) {
1675 int err = snd_pcm_hw_refine(pcm, params);
1676 if (err < 0)
1677 return err;
1678 }
1679 return snd_pcm_hw_param_value(params, var, dir);
1680 }
1681 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1682
snd_pcm_lib_ioctl_reset(struct snd_pcm_substream * substream,void * arg)1683 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1684 void *arg)
1685 {
1686 struct snd_pcm_runtime *runtime = substream->runtime;
1687 unsigned long flags;
1688 snd_pcm_stream_lock_irqsave(substream, flags);
1689 if (snd_pcm_running(substream) &&
1690 snd_pcm_update_hw_ptr(substream) >= 0)
1691 runtime->status->hw_ptr %= runtime->buffer_size;
1692 else {
1693 runtime->status->hw_ptr = 0;
1694 runtime->hw_ptr_wrap = 0;
1695 }
1696 snd_pcm_stream_unlock_irqrestore(substream, flags);
1697 return 0;
1698 }
1699
snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream * substream,void * arg)1700 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1701 void *arg)
1702 {
1703 struct snd_pcm_channel_info *info = arg;
1704 struct snd_pcm_runtime *runtime = substream->runtime;
1705 int width;
1706 if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1707 info->offset = -1;
1708 return 0;
1709 }
1710 width = snd_pcm_format_physical_width(runtime->format);
1711 if (width < 0)
1712 return width;
1713 info->offset = 0;
1714 switch (runtime->access) {
1715 case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1716 case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1717 info->first = info->channel * width;
1718 info->step = runtime->channels * width;
1719 break;
1720 case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1721 case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1722 {
1723 size_t size = runtime->dma_bytes / runtime->channels;
1724 info->first = info->channel * size * 8;
1725 info->step = width;
1726 break;
1727 }
1728 default:
1729 snd_BUG();
1730 break;
1731 }
1732 return 0;
1733 }
1734
snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream * substream,void * arg)1735 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1736 void *arg)
1737 {
1738 struct snd_pcm_hw_params *params = arg;
1739 snd_pcm_format_t format;
1740 int channels;
1741 ssize_t frame_size;
1742
1743 params->fifo_size = substream->runtime->hw.fifo_size;
1744 if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1745 format = params_format(params);
1746 channels = params_channels(params);
1747 frame_size = snd_pcm_format_size(format, channels);
1748 if (frame_size > 0)
1749 params->fifo_size /= frame_size;
1750 }
1751 return 0;
1752 }
1753
1754 /**
1755 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1756 * @substream: the pcm substream instance
1757 * @cmd: ioctl command
1758 * @arg: ioctl argument
1759 *
1760 * Processes the generic ioctl commands for PCM.
1761 * Can be passed as the ioctl callback for PCM ops.
1762 *
1763 * Return: Zero if successful, or a negative error code on failure.
1764 */
snd_pcm_lib_ioctl(struct snd_pcm_substream * substream,unsigned int cmd,void * arg)1765 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1766 unsigned int cmd, void *arg)
1767 {
1768 switch (cmd) {
1769 case SNDRV_PCM_IOCTL1_RESET:
1770 return snd_pcm_lib_ioctl_reset(substream, arg);
1771 case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1772 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1773 case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1774 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1775 }
1776 return -ENXIO;
1777 }
1778 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1779
1780 /**
1781 * snd_pcm_period_elapsed_under_stream_lock() - update the status of runtime for the next period
1782 * under acquired lock of PCM substream.
1783 * @substream: the instance of pcm substream.
1784 *
1785 * This function is called when the batch of audio data frames as the same size as the period of
1786 * buffer is already processed in audio data transmission.
1787 *
1788 * The call of function updates the status of runtime with the latest position of audio data
1789 * transmission, checks overrun and underrun over buffer, awaken user processes from waiting for
1790 * available audio data frames, sampling audio timestamp, and performs stop or drain the PCM
1791 * substream according to configured threshold.
1792 *
1793 * The function is intended to use for the case that PCM driver operates audio data frames under
1794 * acquired lock of PCM substream; e.g. in callback of any operation of &snd_pcm_ops in process
1795 * context. In any interrupt context, it's preferrable to use ``snd_pcm_period_elapsed()`` instead
1796 * since lock of PCM substream should be acquired in advance.
1797 *
1798 * Developer should pay enough attention that some callbacks in &snd_pcm_ops are done by the call of
1799 * function:
1800 *
1801 * - .pointer - to retrieve current position of audio data transmission by frame count or XRUN state.
1802 * - .trigger - with SNDRV_PCM_TRIGGER_STOP at XRUN or DRAINING state.
1803 * - .get_time_info - to retrieve audio time stamp if needed.
1804 *
1805 * Even if more than one periods have elapsed since the last call, you have to call this only once.
1806 */
snd_pcm_period_elapsed_under_stream_lock(struct snd_pcm_substream * substream)1807 void snd_pcm_period_elapsed_under_stream_lock(struct snd_pcm_substream *substream)
1808 {
1809 struct snd_pcm_runtime *runtime;
1810
1811 if (PCM_RUNTIME_CHECK(substream))
1812 return;
1813 runtime = substream->runtime;
1814
1815 if (!snd_pcm_running(substream) ||
1816 snd_pcm_update_hw_ptr0(substream, 1) < 0)
1817 goto _end;
1818
1819 #ifdef CONFIG_SND_PCM_TIMER
1820 if (substream->timer_running)
1821 snd_timer_interrupt(substream->timer, 1);
1822 #endif
1823 _end:
1824 kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1825 }
1826 EXPORT_SYMBOL(snd_pcm_period_elapsed_under_stream_lock);
1827
1828 /**
1829 * snd_pcm_period_elapsed() - update the status of runtime for the next period by acquiring lock of
1830 * PCM substream.
1831 * @substream: the instance of PCM substream.
1832 *
1833 * This function is mostly similar to ``snd_pcm_period_elapsed_under_stream_lock()`` except for
1834 * acquiring lock of PCM substream voluntarily.
1835 *
1836 * It's typically called by any type of IRQ handler when hardware IRQ occurs to notify event that
1837 * the batch of audio data frames as the same size as the period of buffer is already processed in
1838 * audio data transmission.
1839 */
snd_pcm_period_elapsed(struct snd_pcm_substream * substream)1840 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1841 {
1842 unsigned long flags;
1843
1844 if (snd_BUG_ON(!substream))
1845 return;
1846
1847 snd_pcm_stream_lock_irqsave(substream, flags);
1848 snd_pcm_period_elapsed_under_stream_lock(substream);
1849 snd_pcm_stream_unlock_irqrestore(substream, flags);
1850 }
1851 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1852
1853 /*
1854 * Wait until avail_min data becomes available
1855 * Returns a negative error code if any error occurs during operation.
1856 * The available space is stored on availp. When err = 0 and avail = 0
1857 * on the capture stream, it indicates the stream is in DRAINING state.
1858 */
wait_for_avail(struct snd_pcm_substream * substream,snd_pcm_uframes_t * availp)1859 static int wait_for_avail(struct snd_pcm_substream *substream,
1860 snd_pcm_uframes_t *availp)
1861 {
1862 struct snd_pcm_runtime *runtime = substream->runtime;
1863 int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1864 wait_queue_entry_t wait;
1865 int err = 0;
1866 snd_pcm_uframes_t avail = 0;
1867 long wait_time, tout;
1868
1869 init_waitqueue_entry(&wait, current);
1870 set_current_state(TASK_INTERRUPTIBLE);
1871 add_wait_queue(&runtime->tsleep, &wait);
1872
1873 if (runtime->no_period_wakeup)
1874 wait_time = MAX_SCHEDULE_TIMEOUT;
1875 else {
1876 /* use wait time from substream if available */
1877 if (substream->wait_time) {
1878 wait_time = substream->wait_time;
1879 } else {
1880 wait_time = 10;
1881
1882 if (runtime->rate) {
1883 long t = runtime->period_size * 2 /
1884 runtime->rate;
1885 wait_time = max(t, wait_time);
1886 }
1887 wait_time = msecs_to_jiffies(wait_time * 1000);
1888 }
1889 }
1890
1891 for (;;) {
1892 if (signal_pending(current)) {
1893 err = -ERESTARTSYS;
1894 break;
1895 }
1896
1897 /*
1898 * We need to check if space became available already
1899 * (and thus the wakeup happened already) first to close
1900 * the race of space already having become available.
1901 * This check must happen after been added to the waitqueue
1902 * and having current state be INTERRUPTIBLE.
1903 */
1904 avail = snd_pcm_avail(substream);
1905 if (avail >= runtime->twake)
1906 break;
1907 snd_pcm_stream_unlock_irq(substream);
1908
1909 tout = schedule_timeout(wait_time);
1910
1911 snd_pcm_stream_lock_irq(substream);
1912 set_current_state(TASK_INTERRUPTIBLE);
1913 switch (runtime->status->state) {
1914 case SNDRV_PCM_STATE_SUSPENDED:
1915 err = -ESTRPIPE;
1916 goto _endloop;
1917 case SNDRV_PCM_STATE_XRUN:
1918 err = -EPIPE;
1919 goto _endloop;
1920 case SNDRV_PCM_STATE_DRAINING:
1921 if (is_playback)
1922 err = -EPIPE;
1923 else
1924 avail = 0; /* indicate draining */
1925 goto _endloop;
1926 case SNDRV_PCM_STATE_OPEN:
1927 case SNDRV_PCM_STATE_SETUP:
1928 case SNDRV_PCM_STATE_DISCONNECTED:
1929 err = -EBADFD;
1930 goto _endloop;
1931 case SNDRV_PCM_STATE_PAUSED:
1932 continue;
1933 }
1934 if (!tout) {
1935 pcm_dbg(substream->pcm,
1936 "%s write error (DMA or IRQ trouble?)\n",
1937 is_playback ? "playback" : "capture");
1938 err = -EIO;
1939 break;
1940 }
1941 }
1942 _endloop:
1943 set_current_state(TASK_RUNNING);
1944 remove_wait_queue(&runtime->tsleep, &wait);
1945 *availp = avail;
1946 return err;
1947 }
1948
1949 typedef int (*pcm_transfer_f)(struct snd_pcm_substream *substream,
1950 int channel, unsigned long hwoff,
1951 void *buf, unsigned long bytes);
1952
1953 typedef int (*pcm_copy_f)(struct snd_pcm_substream *, snd_pcm_uframes_t, void *,
1954 snd_pcm_uframes_t, snd_pcm_uframes_t, pcm_transfer_f);
1955
1956 /* calculate the target DMA-buffer position to be written/read */
get_dma_ptr(struct snd_pcm_runtime * runtime,int channel,unsigned long hwoff)1957 static void *get_dma_ptr(struct snd_pcm_runtime *runtime,
1958 int channel, unsigned long hwoff)
1959 {
1960 return runtime->dma_area + hwoff +
1961 channel * (runtime->dma_bytes / runtime->channels);
1962 }
1963
1964 /* default copy_user ops for write; used for both interleaved and non- modes */
default_write_copy(struct snd_pcm_substream * substream,int channel,unsigned long hwoff,void * buf,unsigned long bytes)1965 static int default_write_copy(struct snd_pcm_substream *substream,
1966 int channel, unsigned long hwoff,
1967 void *buf, unsigned long bytes)
1968 {
1969 if (copy_from_user(get_dma_ptr(substream->runtime, channel, hwoff),
1970 (void __user *)buf, bytes))
1971 return -EFAULT;
1972 return 0;
1973 }
1974
1975 /* default copy_kernel ops for write */
default_write_copy_kernel(struct snd_pcm_substream * substream,int channel,unsigned long hwoff,void * buf,unsigned long bytes)1976 static int default_write_copy_kernel(struct snd_pcm_substream *substream,
1977 int channel, unsigned long hwoff,
1978 void *buf, unsigned long bytes)
1979 {
1980 memcpy(get_dma_ptr(substream->runtime, channel, hwoff), buf, bytes);
1981 return 0;
1982 }
1983
1984 /* fill silence instead of copy data; called as a transfer helper
1985 * from __snd_pcm_lib_write() or directly from noninterleaved_copy() when
1986 * a NULL buffer is passed
1987 */
fill_silence(struct snd_pcm_substream * substream,int channel,unsigned long hwoff,void * buf,unsigned long bytes)1988 static int fill_silence(struct snd_pcm_substream *substream, int channel,
1989 unsigned long hwoff, void *buf, unsigned long bytes)
1990 {
1991 struct snd_pcm_runtime *runtime = substream->runtime;
1992
1993 if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
1994 return 0;
1995 if (substream->ops->fill_silence)
1996 return substream->ops->fill_silence(substream, channel,
1997 hwoff, bytes);
1998
1999 snd_pcm_format_set_silence(runtime->format,
2000 get_dma_ptr(runtime, channel, hwoff),
2001 bytes_to_samples(runtime, bytes));
2002 return 0;
2003 }
2004
2005 /* default copy_user ops for read; used for both interleaved and non- modes */
default_read_copy(struct snd_pcm_substream * substream,int channel,unsigned long hwoff,void * buf,unsigned long bytes)2006 static int default_read_copy(struct snd_pcm_substream *substream,
2007 int channel, unsigned long hwoff,
2008 void *buf, unsigned long bytes)
2009 {
2010 if (copy_to_user((void __user *)buf,
2011 get_dma_ptr(substream->runtime, channel, hwoff),
2012 bytes))
2013 return -EFAULT;
2014 return 0;
2015 }
2016
2017 /* default copy_kernel ops for read */
default_read_copy_kernel(struct snd_pcm_substream * substream,int channel,unsigned long hwoff,void * buf,unsigned long bytes)2018 static int default_read_copy_kernel(struct snd_pcm_substream *substream,
2019 int channel, unsigned long hwoff,
2020 void *buf, unsigned long bytes)
2021 {
2022 memcpy(buf, get_dma_ptr(substream->runtime, channel, hwoff), bytes);
2023 return 0;
2024 }
2025
2026 /* call transfer function with the converted pointers and sizes;
2027 * for interleaved mode, it's one shot for all samples
2028 */
interleaved_copy(struct snd_pcm_substream * substream,snd_pcm_uframes_t hwoff,void * data,snd_pcm_uframes_t off,snd_pcm_uframes_t frames,pcm_transfer_f transfer)2029 static int interleaved_copy(struct snd_pcm_substream *substream,
2030 snd_pcm_uframes_t hwoff, void *data,
2031 snd_pcm_uframes_t off,
2032 snd_pcm_uframes_t frames,
2033 pcm_transfer_f transfer)
2034 {
2035 struct snd_pcm_runtime *runtime = substream->runtime;
2036
2037 /* convert to bytes */
2038 hwoff = frames_to_bytes(runtime, hwoff);
2039 off = frames_to_bytes(runtime, off);
2040 frames = frames_to_bytes(runtime, frames);
2041 return transfer(substream, 0, hwoff, data + off, frames);
2042 }
2043
2044 /* call transfer function with the converted pointers and sizes for each
2045 * non-interleaved channel; when buffer is NULL, silencing instead of copying
2046 */
noninterleaved_copy(struct snd_pcm_substream * substream,snd_pcm_uframes_t hwoff,void * data,snd_pcm_uframes_t off,snd_pcm_uframes_t frames,pcm_transfer_f transfer)2047 static int noninterleaved_copy(struct snd_pcm_substream *substream,
2048 snd_pcm_uframes_t hwoff, void *data,
2049 snd_pcm_uframes_t off,
2050 snd_pcm_uframes_t frames,
2051 pcm_transfer_f transfer)
2052 {
2053 struct snd_pcm_runtime *runtime = substream->runtime;
2054 int channels = runtime->channels;
2055 void **bufs = data;
2056 int c, err;
2057
2058 /* convert to bytes; note that it's not frames_to_bytes() here.
2059 * in non-interleaved mode, we copy for each channel, thus
2060 * each copy is n_samples bytes x channels = whole frames.
2061 */
2062 off = samples_to_bytes(runtime, off);
2063 frames = samples_to_bytes(runtime, frames);
2064 hwoff = samples_to_bytes(runtime, hwoff);
2065 for (c = 0; c < channels; ++c, ++bufs) {
2066 if (!data || !*bufs)
2067 err = fill_silence(substream, c, hwoff, NULL, frames);
2068 else
2069 err = transfer(substream, c, hwoff, *bufs + off,
2070 frames);
2071 if (err < 0)
2072 return err;
2073 }
2074 return 0;
2075 }
2076
2077 /* fill silence on the given buffer position;
2078 * called from snd_pcm_playback_silence()
2079 */
fill_silence_frames(struct snd_pcm_substream * substream,snd_pcm_uframes_t off,snd_pcm_uframes_t frames)2080 static int fill_silence_frames(struct snd_pcm_substream *substream,
2081 snd_pcm_uframes_t off, snd_pcm_uframes_t frames)
2082 {
2083 if (substream->runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
2084 substream->runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED)
2085 return interleaved_copy(substream, off, NULL, 0, frames,
2086 fill_silence);
2087 else
2088 return noninterleaved_copy(substream, off, NULL, 0, frames,
2089 fill_silence);
2090 }
2091
2092 /* sanity-check for read/write methods */
pcm_sanity_check(struct snd_pcm_substream * substream)2093 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2094 {
2095 struct snd_pcm_runtime *runtime;
2096 if (PCM_RUNTIME_CHECK(substream))
2097 return -ENXIO;
2098 runtime = substream->runtime;
2099 if (snd_BUG_ON(!substream->ops->copy_user && !runtime->dma_area))
2100 return -EINVAL;
2101 if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2102 return -EBADFD;
2103 return 0;
2104 }
2105
pcm_accessible_state(struct snd_pcm_runtime * runtime)2106 static int pcm_accessible_state(struct snd_pcm_runtime *runtime)
2107 {
2108 switch (runtime->status->state) {
2109 case SNDRV_PCM_STATE_PREPARED:
2110 case SNDRV_PCM_STATE_RUNNING:
2111 case SNDRV_PCM_STATE_PAUSED:
2112 return 0;
2113 case SNDRV_PCM_STATE_XRUN:
2114 return -EPIPE;
2115 case SNDRV_PCM_STATE_SUSPENDED:
2116 return -ESTRPIPE;
2117 default:
2118 return -EBADFD;
2119 }
2120 }
2121
2122 /* update to the given appl_ptr and call ack callback if needed;
2123 * when an error is returned, take back to the original value
2124 */
pcm_lib_apply_appl_ptr(struct snd_pcm_substream * substream,snd_pcm_uframes_t appl_ptr)2125 int pcm_lib_apply_appl_ptr(struct snd_pcm_substream *substream,
2126 snd_pcm_uframes_t appl_ptr)
2127 {
2128 struct snd_pcm_runtime *runtime = substream->runtime;
2129 snd_pcm_uframes_t old_appl_ptr = runtime->control->appl_ptr;
2130 int ret;
2131
2132 if (old_appl_ptr == appl_ptr)
2133 return 0;
2134
2135 runtime->control->appl_ptr = appl_ptr;
2136 if (substream->ops->ack) {
2137 ret = substream->ops->ack(substream);
2138 if (ret < 0) {
2139 runtime->control->appl_ptr = old_appl_ptr;
2140 if (ret == -EPIPE)
2141 __snd_pcm_xrun(substream);
2142 return ret;
2143 }
2144 }
2145
2146 trace_applptr(substream, old_appl_ptr, appl_ptr);
2147
2148 return 0;
2149 }
2150
2151 /* the common loop for read/write data */
__snd_pcm_lib_xfer(struct snd_pcm_substream * substream,void * data,bool interleaved,snd_pcm_uframes_t size,bool in_kernel)2152 snd_pcm_sframes_t __snd_pcm_lib_xfer(struct snd_pcm_substream *substream,
2153 void *data, bool interleaved,
2154 snd_pcm_uframes_t size, bool in_kernel)
2155 {
2156 struct snd_pcm_runtime *runtime = substream->runtime;
2157 snd_pcm_uframes_t xfer = 0;
2158 snd_pcm_uframes_t offset = 0;
2159 snd_pcm_uframes_t avail;
2160 pcm_copy_f writer;
2161 pcm_transfer_f transfer;
2162 bool nonblock;
2163 bool is_playback;
2164 int err;
2165
2166 err = pcm_sanity_check(substream);
2167 if (err < 0)
2168 return err;
2169
2170 is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
2171 if (interleaved) {
2172 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2173 runtime->channels > 1)
2174 return -EINVAL;
2175 writer = interleaved_copy;
2176 } else {
2177 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2178 return -EINVAL;
2179 writer = noninterleaved_copy;
2180 }
2181
2182 if (!data) {
2183 if (is_playback)
2184 transfer = fill_silence;
2185 else
2186 return -EINVAL;
2187 } else if (in_kernel) {
2188 if (substream->ops->copy_kernel)
2189 transfer = substream->ops->copy_kernel;
2190 else
2191 transfer = is_playback ?
2192 default_write_copy_kernel : default_read_copy_kernel;
2193 } else {
2194 if (substream->ops->copy_user)
2195 transfer = (pcm_transfer_f)substream->ops->copy_user;
2196 else
2197 transfer = is_playback ?
2198 default_write_copy : default_read_copy;
2199 }
2200
2201 if (size == 0)
2202 return 0;
2203
2204 nonblock = !!(substream->f_flags & O_NONBLOCK);
2205
2206 snd_pcm_stream_lock_irq(substream);
2207 err = pcm_accessible_state(runtime);
2208 if (err < 0)
2209 goto _end_unlock;
2210
2211 runtime->twake = runtime->control->avail_min ? : 1;
2212 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2213 snd_pcm_update_hw_ptr(substream);
2214
2215 /*
2216 * If size < start_threshold, wait indefinitely. Another
2217 * thread may start capture
2218 */
2219 if (!is_playback &&
2220 runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2221 size >= runtime->start_threshold) {
2222 err = snd_pcm_start(substream);
2223 if (err < 0)
2224 goto _end_unlock;
2225 }
2226
2227 avail = snd_pcm_avail(substream);
2228
2229 while (size > 0) {
2230 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2231 snd_pcm_uframes_t cont;
2232 if (!avail) {
2233 if (!is_playback &&
2234 runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
2235 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2236 goto _end_unlock;
2237 }
2238 if (nonblock) {
2239 err = -EAGAIN;
2240 goto _end_unlock;
2241 }
2242 runtime->twake = min_t(snd_pcm_uframes_t, size,
2243 runtime->control->avail_min ? : 1);
2244 err = wait_for_avail(substream, &avail);
2245 if (err < 0)
2246 goto _end_unlock;
2247 if (!avail)
2248 continue; /* draining */
2249 }
2250 frames = size > avail ? avail : size;
2251 appl_ptr = READ_ONCE(runtime->control->appl_ptr);
2252 appl_ofs = appl_ptr % runtime->buffer_size;
2253 cont = runtime->buffer_size - appl_ofs;
2254 if (frames > cont)
2255 frames = cont;
2256 if (snd_BUG_ON(!frames)) {
2257 err = -EINVAL;
2258 goto _end_unlock;
2259 }
2260 if (!atomic_inc_unless_negative(&runtime->buffer_accessing)) {
2261 err = -EBUSY;
2262 goto _end_unlock;
2263 }
2264 snd_pcm_stream_unlock_irq(substream);
2265 err = writer(substream, appl_ofs, data, offset, frames,
2266 transfer);
2267 snd_pcm_stream_lock_irq(substream);
2268 atomic_dec(&runtime->buffer_accessing);
2269 if (err < 0)
2270 goto _end_unlock;
2271 err = pcm_accessible_state(runtime);
2272 if (err < 0)
2273 goto _end_unlock;
2274 appl_ptr += frames;
2275 if (appl_ptr >= runtime->boundary)
2276 appl_ptr -= runtime->boundary;
2277 err = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2278 if (err < 0)
2279 goto _end_unlock;
2280
2281 offset += frames;
2282 size -= frames;
2283 xfer += frames;
2284 avail -= frames;
2285 if (is_playback &&
2286 runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2287 snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2288 err = snd_pcm_start(substream);
2289 if (err < 0)
2290 goto _end_unlock;
2291 }
2292 }
2293 _end_unlock:
2294 runtime->twake = 0;
2295 if (xfer > 0 && err >= 0)
2296 snd_pcm_update_state(substream, runtime);
2297 snd_pcm_stream_unlock_irq(substream);
2298 return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2299 }
2300 EXPORT_SYMBOL(__snd_pcm_lib_xfer);
2301
2302 /*
2303 * standard channel mapping helpers
2304 */
2305
2306 /* default channel maps for multi-channel playbacks, up to 8 channels */
2307 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2308 { .channels = 1,
2309 .map = { SNDRV_CHMAP_MONO } },
2310 { .channels = 2,
2311 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2312 { .channels = 4,
2313 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2314 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2315 { .channels = 6,
2316 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2317 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2318 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2319 { .channels = 8,
2320 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2321 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2322 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2323 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2324 { }
2325 };
2326 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2327
2328 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2329 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2330 { .channels = 1,
2331 .map = { SNDRV_CHMAP_MONO } },
2332 { .channels = 2,
2333 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2334 { .channels = 4,
2335 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2336 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2337 { .channels = 6,
2338 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2339 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2340 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2341 { .channels = 8,
2342 .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2343 SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2344 SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2345 SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2346 { }
2347 };
2348 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2349
valid_chmap_channels(const struct snd_pcm_chmap * info,int ch)2350 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2351 {
2352 if (ch > info->max_channels)
2353 return false;
2354 return !info->channel_mask || (info->channel_mask & (1U << ch));
2355 }
2356
pcm_chmap_ctl_info(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_info * uinfo)2357 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2358 struct snd_ctl_elem_info *uinfo)
2359 {
2360 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2361
2362 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2363 uinfo->count = info->max_channels;
2364 uinfo->value.integer.min = 0;
2365 uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2366 return 0;
2367 }
2368
2369 /* get callback for channel map ctl element
2370 * stores the channel position firstly matching with the current channels
2371 */
pcm_chmap_ctl_get(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_value * ucontrol)2372 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2373 struct snd_ctl_elem_value *ucontrol)
2374 {
2375 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2376 unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2377 struct snd_pcm_substream *substream;
2378 const struct snd_pcm_chmap_elem *map;
2379
2380 if (!info->chmap)
2381 return -EINVAL;
2382 substream = snd_pcm_chmap_substream(info, idx);
2383 if (!substream)
2384 return -ENODEV;
2385 memset(ucontrol->value.integer.value, 0,
2386 sizeof(long) * info->max_channels);
2387 if (!substream->runtime)
2388 return 0; /* no channels set */
2389 for (map = info->chmap; map->channels; map++) {
2390 int i;
2391 if (map->channels == substream->runtime->channels &&
2392 valid_chmap_channels(info, map->channels)) {
2393 for (i = 0; i < map->channels; i++)
2394 ucontrol->value.integer.value[i] = map->map[i];
2395 return 0;
2396 }
2397 }
2398 return -EINVAL;
2399 }
2400
2401 /* tlv callback for channel map ctl element
2402 * expands the pre-defined channel maps in a form of TLV
2403 */
pcm_chmap_ctl_tlv(struct snd_kcontrol * kcontrol,int op_flag,unsigned int size,unsigned int __user * tlv)2404 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2405 unsigned int size, unsigned int __user *tlv)
2406 {
2407 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2408 const struct snd_pcm_chmap_elem *map;
2409 unsigned int __user *dst;
2410 int c, count = 0;
2411
2412 if (!info->chmap)
2413 return -EINVAL;
2414 if (size < 8)
2415 return -ENOMEM;
2416 if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2417 return -EFAULT;
2418 size -= 8;
2419 dst = tlv + 2;
2420 for (map = info->chmap; map->channels; map++) {
2421 int chs_bytes = map->channels * 4;
2422 if (!valid_chmap_channels(info, map->channels))
2423 continue;
2424 if (size < 8)
2425 return -ENOMEM;
2426 if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2427 put_user(chs_bytes, dst + 1))
2428 return -EFAULT;
2429 dst += 2;
2430 size -= 8;
2431 count += 8;
2432 if (size < chs_bytes)
2433 return -ENOMEM;
2434 size -= chs_bytes;
2435 count += chs_bytes;
2436 for (c = 0; c < map->channels; c++) {
2437 if (put_user(map->map[c], dst))
2438 return -EFAULT;
2439 dst++;
2440 }
2441 }
2442 if (put_user(count, tlv + 1))
2443 return -EFAULT;
2444 return 0;
2445 }
2446
pcm_chmap_ctl_private_free(struct snd_kcontrol * kcontrol)2447 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2448 {
2449 struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2450 info->pcm->streams[info->stream].chmap_kctl = NULL;
2451 kfree(info);
2452 }
2453
2454 /**
2455 * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2456 * @pcm: the assigned PCM instance
2457 * @stream: stream direction
2458 * @chmap: channel map elements (for query)
2459 * @max_channels: the max number of channels for the stream
2460 * @private_value: the value passed to each kcontrol's private_value field
2461 * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2462 *
2463 * Create channel-mapping control elements assigned to the given PCM stream(s).
2464 * Return: Zero if successful, or a negative error value.
2465 */
snd_pcm_add_chmap_ctls(struct snd_pcm * pcm,int stream,const struct snd_pcm_chmap_elem * chmap,int max_channels,unsigned long private_value,struct snd_pcm_chmap ** info_ret)2466 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2467 const struct snd_pcm_chmap_elem *chmap,
2468 int max_channels,
2469 unsigned long private_value,
2470 struct snd_pcm_chmap **info_ret)
2471 {
2472 struct snd_pcm_chmap *info;
2473 struct snd_kcontrol_new knew = {
2474 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
2475 .access = SNDRV_CTL_ELEM_ACCESS_READ |
2476 SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2477 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2478 .info = pcm_chmap_ctl_info,
2479 .get = pcm_chmap_ctl_get,
2480 .tlv.c = pcm_chmap_ctl_tlv,
2481 };
2482 int err;
2483
2484 if (WARN_ON(pcm->streams[stream].chmap_kctl))
2485 return -EBUSY;
2486 info = kzalloc(sizeof(*info), GFP_KERNEL);
2487 if (!info)
2488 return -ENOMEM;
2489 info->pcm = pcm;
2490 info->stream = stream;
2491 info->chmap = chmap;
2492 info->max_channels = max_channels;
2493 if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2494 knew.name = "Playback Channel Map";
2495 else
2496 knew.name = "Capture Channel Map";
2497 knew.device = pcm->device;
2498 knew.count = pcm->streams[stream].substream_count;
2499 knew.private_value = private_value;
2500 info->kctl = snd_ctl_new1(&knew, info);
2501 if (!info->kctl) {
2502 kfree(info);
2503 return -ENOMEM;
2504 }
2505 info->kctl->private_free = pcm_chmap_ctl_private_free;
2506 err = snd_ctl_add(pcm->card, info->kctl);
2507 if (err < 0)
2508 return err;
2509 pcm->streams[stream].chmap_kctl = info->kctl;
2510 if (info_ret)
2511 *info_ret = info;
2512 return 0;
2513 }
2514 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);
2515