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1 /*
2  *  Digital Audio (PCM) abstract layer
3  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4  *                   Abramo Bagnara <abramo@alsa-project.org>
5  *
6  *
7  *   This program is free software; you can redistribute it and/or modify
8  *   it under the terms of the GNU General Public License as published by
9  *   the Free Software Foundation; either version 2 of the License, or
10  *   (at your option) any later version.
11  *
12  *   This program is distributed in the hope that it will be useful,
13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *   GNU General Public License for more details.
16  *
17  *   You should have received a copy of the GNU General Public License
18  *   along with this program; if not, write to the Free Software
19  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
20  *
21  */
22 
23 #include <linux/slab.h>
24 #include <linux/sched/signal.h>
25 #include <linux/time.h>
26 #include <linux/math64.h>
27 #include <linux/export.h>
28 #include <sound/core.h>
29 #include <sound/control.h>
30 #include <sound/tlv.h>
31 #include <sound/info.h>
32 #include <sound/pcm.h>
33 #include <sound/pcm_params.h>
34 #include <sound/timer.h>
35 
36 #include "pcm_local.h"
37 
38 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
39 #define CREATE_TRACE_POINTS
40 #include "pcm_trace.h"
41 #else
42 #define trace_hwptr(substream, pos, in_interrupt)
43 #define trace_xrun(substream)
44 #define trace_hw_ptr_error(substream, reason)
45 #define trace_applptr(substream, prev, curr)
46 #endif
47 
48 static int fill_silence_frames(struct snd_pcm_substream *substream,
49 			       snd_pcm_uframes_t off, snd_pcm_uframes_t frames);
50 
51 /*
52  * fill ring buffer with silence
53  * runtime->silence_start: starting pointer to silence area
54  * runtime->silence_filled: size filled with silence
55  * runtime->silence_threshold: threshold from application
56  * runtime->silence_size: maximal size from application
57  *
58  * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
59  */
snd_pcm_playback_silence(struct snd_pcm_substream * substream,snd_pcm_uframes_t new_hw_ptr)60 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
61 {
62 	struct snd_pcm_runtime *runtime = substream->runtime;
63 	snd_pcm_uframes_t frames, ofs, transfer;
64 	int err;
65 
66 	if (runtime->silence_size < runtime->boundary) {
67 		snd_pcm_sframes_t noise_dist, n;
68 		snd_pcm_uframes_t appl_ptr = READ_ONCE(runtime->control->appl_ptr);
69 		if (runtime->silence_start != appl_ptr) {
70 			n = appl_ptr - runtime->silence_start;
71 			if (n < 0)
72 				n += runtime->boundary;
73 			if ((snd_pcm_uframes_t)n < runtime->silence_filled)
74 				runtime->silence_filled -= n;
75 			else
76 				runtime->silence_filled = 0;
77 			runtime->silence_start = appl_ptr;
78 		}
79 		if (runtime->silence_filled >= runtime->buffer_size)
80 			return;
81 		noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
82 		if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
83 			return;
84 		frames = runtime->silence_threshold - noise_dist;
85 		if (frames > runtime->silence_size)
86 			frames = runtime->silence_size;
87 	} else {
88 		if (new_hw_ptr == ULONG_MAX) {	/* initialization */
89 			snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
90 			if (avail > runtime->buffer_size)
91 				avail = runtime->buffer_size;
92 			runtime->silence_filled = avail > 0 ? avail : 0;
93 			runtime->silence_start = (runtime->status->hw_ptr +
94 						  runtime->silence_filled) %
95 						 runtime->boundary;
96 		} else {
97 			ofs = runtime->status->hw_ptr;
98 			frames = new_hw_ptr - ofs;
99 			if ((snd_pcm_sframes_t)frames < 0)
100 				frames += runtime->boundary;
101 			runtime->silence_filled -= frames;
102 			if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
103 				runtime->silence_filled = 0;
104 				runtime->silence_start = new_hw_ptr;
105 			} else {
106 				runtime->silence_start = ofs;
107 			}
108 		}
109 		frames = runtime->buffer_size - runtime->silence_filled;
110 	}
111 	if (snd_BUG_ON(frames > runtime->buffer_size))
112 		return;
113 	if (frames == 0)
114 		return;
115 	ofs = runtime->silence_start % runtime->buffer_size;
116 	while (frames > 0) {
117 		transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
118 		err = fill_silence_frames(substream, ofs, transfer);
119 		snd_BUG_ON(err < 0);
120 		runtime->silence_filled += transfer;
121 		frames -= transfer;
122 		ofs = 0;
123 	}
124 }
125 
126 #ifdef CONFIG_SND_DEBUG
snd_pcm_debug_name(struct snd_pcm_substream * substream,char * name,size_t len)127 void snd_pcm_debug_name(struct snd_pcm_substream *substream,
128 			   char *name, size_t len)
129 {
130 	snprintf(name, len, "pcmC%dD%d%c:%d",
131 		 substream->pcm->card->number,
132 		 substream->pcm->device,
133 		 substream->stream ? 'c' : 'p',
134 		 substream->number);
135 }
136 EXPORT_SYMBOL(snd_pcm_debug_name);
137 #endif
138 
139 #define XRUN_DEBUG_BASIC	(1<<0)
140 #define XRUN_DEBUG_STACK	(1<<1)	/* dump also stack */
141 #define XRUN_DEBUG_JIFFIESCHECK	(1<<2)	/* do jiffies check */
142 
143 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
144 
145 #define xrun_debug(substream, mask) \
146 			((substream)->pstr->xrun_debug & (mask))
147 #else
148 #define xrun_debug(substream, mask)	0
149 #endif
150 
151 #define dump_stack_on_xrun(substream) do {			\
152 		if (xrun_debug(substream, XRUN_DEBUG_STACK))	\
153 			dump_stack();				\
154 	} while (0)
155 
xrun(struct snd_pcm_substream * substream)156 static void xrun(struct snd_pcm_substream *substream)
157 {
158 	struct snd_pcm_runtime *runtime = substream->runtime;
159 
160 	trace_xrun(substream);
161 	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
162 		snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
163 	snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
164 	if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
165 		char name[16];
166 		snd_pcm_debug_name(substream, name, sizeof(name));
167 		pcm_warn(substream->pcm, "XRUN: %s\n", name);
168 		dump_stack_on_xrun(substream);
169 	}
170 }
171 
172 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
173 #define hw_ptr_error(substream, in_interrupt, reason, fmt, args...)	\
174 	do {								\
175 		trace_hw_ptr_error(substream, reason);	\
176 		if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {		\
177 			pr_err_ratelimited("ALSA: PCM: [%c] " reason ": " fmt, \
178 					   (in_interrupt) ? 'Q' : 'P', ##args);	\
179 			dump_stack_on_xrun(substream);			\
180 		}							\
181 	} while (0)
182 
183 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
184 
185 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
186 
187 #endif
188 
snd_pcm_update_state(struct snd_pcm_substream * substream,struct snd_pcm_runtime * runtime)189 int snd_pcm_update_state(struct snd_pcm_substream *substream,
190 			 struct snd_pcm_runtime *runtime)
191 {
192 	snd_pcm_uframes_t avail;
193 
194 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
195 		avail = snd_pcm_playback_avail(runtime);
196 	else
197 		avail = snd_pcm_capture_avail(runtime);
198 	if (avail > runtime->avail_max)
199 		runtime->avail_max = avail;
200 	if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
201 		if (avail >= runtime->buffer_size) {
202 			snd_pcm_drain_done(substream);
203 			return -EPIPE;
204 		}
205 	} else {
206 		if (avail >= runtime->stop_threshold) {
207 			xrun(substream);
208 			return -EPIPE;
209 		}
210 	}
211 	if (runtime->twake) {
212 		if (avail >= runtime->twake)
213 			wake_up(&runtime->tsleep);
214 	} else if (avail >= runtime->control->avail_min)
215 		wake_up(&runtime->sleep);
216 	return 0;
217 }
218 
update_audio_tstamp(struct snd_pcm_substream * substream,struct timespec * curr_tstamp,struct timespec * audio_tstamp)219 static void update_audio_tstamp(struct snd_pcm_substream *substream,
220 				struct timespec *curr_tstamp,
221 				struct timespec *audio_tstamp)
222 {
223 	struct snd_pcm_runtime *runtime = substream->runtime;
224 	u64 audio_frames, audio_nsecs;
225 	struct timespec driver_tstamp;
226 
227 	if (runtime->tstamp_mode != SNDRV_PCM_TSTAMP_ENABLE)
228 		return;
229 
230 	if (!(substream->ops->get_time_info) ||
231 		(runtime->audio_tstamp_report.actual_type ==
232 			SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
233 
234 		/*
235 		 * provide audio timestamp derived from pointer position
236 		 * add delay only if requested
237 		 */
238 
239 		audio_frames = runtime->hw_ptr_wrap + runtime->status->hw_ptr;
240 
241 		if (runtime->audio_tstamp_config.report_delay) {
242 			if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
243 				audio_frames -=  runtime->delay;
244 			else
245 				audio_frames +=  runtime->delay;
246 		}
247 		audio_nsecs = div_u64(audio_frames * 1000000000LL,
248 				runtime->rate);
249 		*audio_tstamp = ns_to_timespec(audio_nsecs);
250 	}
251 	if (!timespec_equal(&runtime->status->audio_tstamp, audio_tstamp)) {
252 		runtime->status->audio_tstamp = *audio_tstamp;
253 		runtime->status->tstamp = *curr_tstamp;
254 	}
255 
256 	/*
257 	 * re-take a driver timestamp to let apps detect if the reference tstamp
258 	 * read by low-level hardware was provided with a delay
259 	 */
260 	snd_pcm_gettime(substream->runtime, (struct timespec *)&driver_tstamp);
261 	runtime->driver_tstamp = driver_tstamp;
262 }
263 
snd_pcm_update_hw_ptr0(struct snd_pcm_substream * substream,unsigned int in_interrupt)264 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
265 				  unsigned int in_interrupt)
266 {
267 	struct snd_pcm_runtime *runtime = substream->runtime;
268 	snd_pcm_uframes_t pos;
269 	snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
270 	snd_pcm_sframes_t hdelta, delta;
271 	unsigned long jdelta;
272 	unsigned long curr_jiffies;
273 	struct timespec curr_tstamp;
274 	struct timespec audio_tstamp;
275 	int crossed_boundary = 0;
276 
277 	old_hw_ptr = runtime->status->hw_ptr;
278 
279 	/*
280 	 * group pointer, time and jiffies reads to allow for more
281 	 * accurate correlations/corrections.
282 	 * The values are stored at the end of this routine after
283 	 * corrections for hw_ptr position
284 	 */
285 	pos = substream->ops->pointer(substream);
286 	curr_jiffies = jiffies;
287 	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
288 		if ((substream->ops->get_time_info) &&
289 			(runtime->audio_tstamp_config.type_requested != SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
290 			substream->ops->get_time_info(substream, &curr_tstamp,
291 						&audio_tstamp,
292 						&runtime->audio_tstamp_config,
293 						&runtime->audio_tstamp_report);
294 
295 			/* re-test in case tstamp type is not supported in hardware and was demoted to DEFAULT */
296 			if (runtime->audio_tstamp_report.actual_type == SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)
297 				snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
298 		} else
299 			snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
300 	}
301 
302 	if (pos == SNDRV_PCM_POS_XRUN) {
303 		xrun(substream);
304 		return -EPIPE;
305 	}
306 	if (pos >= runtime->buffer_size) {
307 		if (printk_ratelimit()) {
308 			char name[16];
309 			snd_pcm_debug_name(substream, name, sizeof(name));
310 			pcm_err(substream->pcm,
311 				"invalid position: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
312 				name, pos, runtime->buffer_size,
313 				runtime->period_size);
314 		}
315 		pos = 0;
316 	}
317 	pos -= pos % runtime->min_align;
318 	trace_hwptr(substream, pos, in_interrupt);
319 	hw_base = runtime->hw_ptr_base;
320 	new_hw_ptr = hw_base + pos;
321 	if (in_interrupt) {
322 		/* we know that one period was processed */
323 		/* delta = "expected next hw_ptr" for in_interrupt != 0 */
324 		delta = runtime->hw_ptr_interrupt + runtime->period_size;
325 		if (delta > new_hw_ptr) {
326 			/* check for double acknowledged interrupts */
327 			hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
328 			if (hdelta > runtime->hw_ptr_buffer_jiffies/2 + 1) {
329 				hw_base += runtime->buffer_size;
330 				if (hw_base >= runtime->boundary) {
331 					hw_base = 0;
332 					crossed_boundary++;
333 				}
334 				new_hw_ptr = hw_base + pos;
335 				goto __delta;
336 			}
337 		}
338 	}
339 	/* new_hw_ptr might be lower than old_hw_ptr in case when */
340 	/* pointer crosses the end of the ring buffer */
341 	if (new_hw_ptr < old_hw_ptr) {
342 		hw_base += runtime->buffer_size;
343 		if (hw_base >= runtime->boundary) {
344 			hw_base = 0;
345 			crossed_boundary++;
346 		}
347 		new_hw_ptr = hw_base + pos;
348 	}
349       __delta:
350 	delta = new_hw_ptr - old_hw_ptr;
351 	if (delta < 0)
352 		delta += runtime->boundary;
353 
354 	if (runtime->no_period_wakeup) {
355 		snd_pcm_sframes_t xrun_threshold;
356 		/*
357 		 * Without regular period interrupts, we have to check
358 		 * the elapsed time to detect xruns.
359 		 */
360 		jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
361 		if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
362 			goto no_delta_check;
363 		hdelta = jdelta - delta * HZ / runtime->rate;
364 		xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
365 		while (hdelta > xrun_threshold) {
366 			delta += runtime->buffer_size;
367 			hw_base += runtime->buffer_size;
368 			if (hw_base >= runtime->boundary) {
369 				hw_base = 0;
370 				crossed_boundary++;
371 			}
372 			new_hw_ptr = hw_base + pos;
373 			hdelta -= runtime->hw_ptr_buffer_jiffies;
374 		}
375 		goto no_delta_check;
376 	}
377 
378 	/* something must be really wrong */
379 	if (delta >= runtime->buffer_size + runtime->period_size) {
380 		hw_ptr_error(substream, in_interrupt, "Unexpected hw_ptr",
381 			     "(stream=%i, pos=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
382 			     substream->stream, (long)pos,
383 			     (long)new_hw_ptr, (long)old_hw_ptr);
384 		return 0;
385 	}
386 
387 	/* Do jiffies check only in xrun_debug mode */
388 	if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
389 		goto no_jiffies_check;
390 
391 	/* Skip the jiffies check for hardwares with BATCH flag.
392 	 * Such hardware usually just increases the position at each IRQ,
393 	 * thus it can't give any strange position.
394 	 */
395 	if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
396 		goto no_jiffies_check;
397 	hdelta = delta;
398 	if (hdelta < runtime->delay)
399 		goto no_jiffies_check;
400 	hdelta -= runtime->delay;
401 	jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
402 	if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
403 		delta = jdelta /
404 			(((runtime->period_size * HZ) / runtime->rate)
405 								+ HZ/100);
406 		/* move new_hw_ptr according jiffies not pos variable */
407 		new_hw_ptr = old_hw_ptr;
408 		hw_base = delta;
409 		/* use loop to avoid checks for delta overflows */
410 		/* the delta value is small or zero in most cases */
411 		while (delta > 0) {
412 			new_hw_ptr += runtime->period_size;
413 			if (new_hw_ptr >= runtime->boundary) {
414 				new_hw_ptr -= runtime->boundary;
415 				crossed_boundary--;
416 			}
417 			delta--;
418 		}
419 		/* align hw_base to buffer_size */
420 		hw_ptr_error(substream, in_interrupt, "hw_ptr skipping",
421 			     "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
422 			     (long)pos, (long)hdelta,
423 			     (long)runtime->period_size, jdelta,
424 			     ((hdelta * HZ) / runtime->rate), hw_base,
425 			     (unsigned long)old_hw_ptr,
426 			     (unsigned long)new_hw_ptr);
427 		/* reset values to proper state */
428 		delta = 0;
429 		hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
430 	}
431  no_jiffies_check:
432 	if (delta > runtime->period_size + runtime->period_size / 2) {
433 		hw_ptr_error(substream, in_interrupt,
434 			     "Lost interrupts?",
435 			     "(stream=%i, delta=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
436 			     substream->stream, (long)delta,
437 			     (long)new_hw_ptr,
438 			     (long)old_hw_ptr);
439 	}
440 
441  no_delta_check:
442 	if (runtime->status->hw_ptr == new_hw_ptr) {
443 		update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
444 		return 0;
445 	}
446 
447 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
448 	    runtime->silence_size > 0)
449 		snd_pcm_playback_silence(substream, new_hw_ptr);
450 
451 	if (in_interrupt) {
452 		delta = new_hw_ptr - runtime->hw_ptr_interrupt;
453 		if (delta < 0)
454 			delta += runtime->boundary;
455 		delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
456 		runtime->hw_ptr_interrupt += delta;
457 		if (runtime->hw_ptr_interrupt >= runtime->boundary)
458 			runtime->hw_ptr_interrupt -= runtime->boundary;
459 	}
460 	runtime->hw_ptr_base = hw_base;
461 	runtime->status->hw_ptr = new_hw_ptr;
462 	runtime->hw_ptr_jiffies = curr_jiffies;
463 	if (crossed_boundary) {
464 		snd_BUG_ON(crossed_boundary != 1);
465 		runtime->hw_ptr_wrap += runtime->boundary;
466 	}
467 
468 	update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
469 
470 	return snd_pcm_update_state(substream, runtime);
471 }
472 
473 /* CAUTION: call it with irq disabled */
snd_pcm_update_hw_ptr(struct snd_pcm_substream * substream)474 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
475 {
476 	return snd_pcm_update_hw_ptr0(substream, 0);
477 }
478 
479 /**
480  * snd_pcm_set_ops - set the PCM operators
481  * @pcm: the pcm instance
482  * @direction: stream direction, SNDRV_PCM_STREAM_XXX
483  * @ops: the operator table
484  *
485  * Sets the given PCM operators to the pcm instance.
486  */
snd_pcm_set_ops(struct snd_pcm * pcm,int direction,const struct snd_pcm_ops * ops)487 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
488 		     const struct snd_pcm_ops *ops)
489 {
490 	struct snd_pcm_str *stream = &pcm->streams[direction];
491 	struct snd_pcm_substream *substream;
492 
493 	for (substream = stream->substream; substream != NULL; substream = substream->next)
494 		substream->ops = ops;
495 }
496 EXPORT_SYMBOL(snd_pcm_set_ops);
497 
498 /**
499  * snd_pcm_sync - set the PCM sync id
500  * @substream: the pcm substream
501  *
502  * Sets the PCM sync identifier for the card.
503  */
snd_pcm_set_sync(struct snd_pcm_substream * substream)504 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
505 {
506 	struct snd_pcm_runtime *runtime = substream->runtime;
507 
508 	runtime->sync.id32[0] = substream->pcm->card->number;
509 	runtime->sync.id32[1] = -1;
510 	runtime->sync.id32[2] = -1;
511 	runtime->sync.id32[3] = -1;
512 }
513 EXPORT_SYMBOL(snd_pcm_set_sync);
514 
515 /*
516  *  Standard ioctl routine
517  */
518 
div32(unsigned int a,unsigned int b,unsigned int * r)519 static inline unsigned int div32(unsigned int a, unsigned int b,
520 				 unsigned int *r)
521 {
522 	if (b == 0) {
523 		*r = 0;
524 		return UINT_MAX;
525 	}
526 	*r = a % b;
527 	return a / b;
528 }
529 
div_down(unsigned int a,unsigned int b)530 static inline unsigned int div_down(unsigned int a, unsigned int b)
531 {
532 	if (b == 0)
533 		return UINT_MAX;
534 	return a / b;
535 }
536 
div_up(unsigned int a,unsigned int b)537 static inline unsigned int div_up(unsigned int a, unsigned int b)
538 {
539 	unsigned int r;
540 	unsigned int q;
541 	if (b == 0)
542 		return UINT_MAX;
543 	q = div32(a, b, &r);
544 	if (r)
545 		++q;
546 	return q;
547 }
548 
mul(unsigned int a,unsigned int b)549 static inline unsigned int mul(unsigned int a, unsigned int b)
550 {
551 	if (a == 0)
552 		return 0;
553 	if (div_down(UINT_MAX, a) < b)
554 		return UINT_MAX;
555 	return a * b;
556 }
557 
muldiv32(unsigned int a,unsigned int b,unsigned int c,unsigned int * r)558 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
559 				    unsigned int c, unsigned int *r)
560 {
561 	u_int64_t n = (u_int64_t) a * b;
562 	if (c == 0) {
563 		*r = 0;
564 		return UINT_MAX;
565 	}
566 	n = div_u64_rem(n, c, r);
567 	if (n >= UINT_MAX) {
568 		*r = 0;
569 		return UINT_MAX;
570 	}
571 	return n;
572 }
573 
574 /**
575  * snd_interval_refine - refine the interval value of configurator
576  * @i: the interval value to refine
577  * @v: the interval value to refer to
578  *
579  * Refines the interval value with the reference value.
580  * The interval is changed to the range satisfying both intervals.
581  * The interval status (min, max, integer, etc.) are evaluated.
582  *
583  * Return: Positive if the value is changed, zero if it's not changed, or a
584  * negative error code.
585  */
snd_interval_refine(struct snd_interval * i,const struct snd_interval * v)586 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
587 {
588 	int changed = 0;
589 	if (snd_BUG_ON(snd_interval_empty(i)))
590 		return -EINVAL;
591 	if (i->min < v->min) {
592 		i->min = v->min;
593 		i->openmin = v->openmin;
594 		changed = 1;
595 	} else if (i->min == v->min && !i->openmin && v->openmin) {
596 		i->openmin = 1;
597 		changed = 1;
598 	}
599 	if (i->max > v->max) {
600 		i->max = v->max;
601 		i->openmax = v->openmax;
602 		changed = 1;
603 	} else if (i->max == v->max && !i->openmax && v->openmax) {
604 		i->openmax = 1;
605 		changed = 1;
606 	}
607 	if (!i->integer && v->integer) {
608 		i->integer = 1;
609 		changed = 1;
610 	}
611 	if (i->integer) {
612 		if (i->openmin) {
613 			i->min++;
614 			i->openmin = 0;
615 		}
616 		if (i->openmax) {
617 			i->max--;
618 			i->openmax = 0;
619 		}
620 	} else if (!i->openmin && !i->openmax && i->min == i->max)
621 		i->integer = 1;
622 	if (snd_interval_checkempty(i)) {
623 		snd_interval_none(i);
624 		return -EINVAL;
625 	}
626 	return changed;
627 }
628 EXPORT_SYMBOL(snd_interval_refine);
629 
snd_interval_refine_first(struct snd_interval * i)630 static int snd_interval_refine_first(struct snd_interval *i)
631 {
632 	const unsigned int last_max = i->max;
633 
634 	if (snd_BUG_ON(snd_interval_empty(i)))
635 		return -EINVAL;
636 	if (snd_interval_single(i))
637 		return 0;
638 	i->max = i->min;
639 	if (i->openmin)
640 		i->max++;
641 	/* only exclude max value if also excluded before refine */
642 	i->openmax = (i->openmax && i->max >= last_max);
643 	return 1;
644 }
645 
snd_interval_refine_last(struct snd_interval * i)646 static int snd_interval_refine_last(struct snd_interval *i)
647 {
648 	const unsigned int last_min = i->min;
649 
650 	if (snd_BUG_ON(snd_interval_empty(i)))
651 		return -EINVAL;
652 	if (snd_interval_single(i))
653 		return 0;
654 	i->min = i->max;
655 	if (i->openmax)
656 		i->min--;
657 	/* only exclude min value if also excluded before refine */
658 	i->openmin = (i->openmin && i->min <= last_min);
659 	return 1;
660 }
661 
snd_interval_mul(const struct snd_interval * a,const struct snd_interval * b,struct snd_interval * c)662 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
663 {
664 	if (a->empty || b->empty) {
665 		snd_interval_none(c);
666 		return;
667 	}
668 	c->empty = 0;
669 	c->min = mul(a->min, b->min);
670 	c->openmin = (a->openmin || b->openmin);
671 	c->max = mul(a->max,  b->max);
672 	c->openmax = (a->openmax || b->openmax);
673 	c->integer = (a->integer && b->integer);
674 }
675 
676 /**
677  * snd_interval_div - refine the interval value with division
678  * @a: dividend
679  * @b: divisor
680  * @c: quotient
681  *
682  * c = a / b
683  *
684  * Returns non-zero if the value is changed, zero if not changed.
685  */
snd_interval_div(const struct snd_interval * a,const struct snd_interval * b,struct snd_interval * c)686 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
687 {
688 	unsigned int r;
689 	if (a->empty || b->empty) {
690 		snd_interval_none(c);
691 		return;
692 	}
693 	c->empty = 0;
694 	c->min = div32(a->min, b->max, &r);
695 	c->openmin = (r || a->openmin || b->openmax);
696 	if (b->min > 0) {
697 		c->max = div32(a->max, b->min, &r);
698 		if (r) {
699 			c->max++;
700 			c->openmax = 1;
701 		} else
702 			c->openmax = (a->openmax || b->openmin);
703 	} else {
704 		c->max = UINT_MAX;
705 		c->openmax = 0;
706 	}
707 	c->integer = 0;
708 }
709 
710 /**
711  * snd_interval_muldivk - refine the interval value
712  * @a: dividend 1
713  * @b: dividend 2
714  * @k: divisor (as integer)
715  * @c: result
716   *
717  * c = a * b / k
718  *
719  * Returns non-zero if the value is changed, zero if not changed.
720  */
snd_interval_muldivk(const struct snd_interval * a,const struct snd_interval * b,unsigned int k,struct snd_interval * c)721 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
722 		      unsigned int k, struct snd_interval *c)
723 {
724 	unsigned int r;
725 	if (a->empty || b->empty) {
726 		snd_interval_none(c);
727 		return;
728 	}
729 	c->empty = 0;
730 	c->min = muldiv32(a->min, b->min, k, &r);
731 	c->openmin = (r || a->openmin || b->openmin);
732 	c->max = muldiv32(a->max, b->max, k, &r);
733 	if (r) {
734 		c->max++;
735 		c->openmax = 1;
736 	} else
737 		c->openmax = (a->openmax || b->openmax);
738 	c->integer = 0;
739 }
740 
741 /**
742  * snd_interval_mulkdiv - refine the interval value
743  * @a: dividend 1
744  * @k: dividend 2 (as integer)
745  * @b: divisor
746  * @c: result
747  *
748  * c = a * k / b
749  *
750  * Returns non-zero if the value is changed, zero if not changed.
751  */
snd_interval_mulkdiv(const struct snd_interval * a,unsigned int k,const struct snd_interval * b,struct snd_interval * c)752 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
753 		      const struct snd_interval *b, struct snd_interval *c)
754 {
755 	unsigned int r;
756 	if (a->empty || b->empty) {
757 		snd_interval_none(c);
758 		return;
759 	}
760 	c->empty = 0;
761 	c->min = muldiv32(a->min, k, b->max, &r);
762 	c->openmin = (r || a->openmin || b->openmax);
763 	if (b->min > 0) {
764 		c->max = muldiv32(a->max, k, b->min, &r);
765 		if (r) {
766 			c->max++;
767 			c->openmax = 1;
768 		} else
769 			c->openmax = (a->openmax || b->openmin);
770 	} else {
771 		c->max = UINT_MAX;
772 		c->openmax = 0;
773 	}
774 	c->integer = 0;
775 }
776 
777 /* ---- */
778 
779 
780 /**
781  * snd_interval_ratnum - refine the interval value
782  * @i: interval to refine
783  * @rats_count: number of ratnum_t
784  * @rats: ratnum_t array
785  * @nump: pointer to store the resultant numerator
786  * @denp: pointer to store the resultant denominator
787  *
788  * Return: Positive if the value is changed, zero if it's not changed, or a
789  * negative error code.
790  */
snd_interval_ratnum(struct snd_interval * i,unsigned int rats_count,const struct snd_ratnum * rats,unsigned int * nump,unsigned int * denp)791 int snd_interval_ratnum(struct snd_interval *i,
792 			unsigned int rats_count, const struct snd_ratnum *rats,
793 			unsigned int *nump, unsigned int *denp)
794 {
795 	unsigned int best_num, best_den;
796 	int best_diff;
797 	unsigned int k;
798 	struct snd_interval t;
799 	int err;
800 	unsigned int result_num, result_den;
801 	int result_diff;
802 
803 	best_num = best_den = best_diff = 0;
804 	for (k = 0; k < rats_count; ++k) {
805 		unsigned int num = rats[k].num;
806 		unsigned int den;
807 		unsigned int q = i->min;
808 		int diff;
809 		if (q == 0)
810 			q = 1;
811 		den = div_up(num, q);
812 		if (den < rats[k].den_min)
813 			continue;
814 		if (den > rats[k].den_max)
815 			den = rats[k].den_max;
816 		else {
817 			unsigned int r;
818 			r = (den - rats[k].den_min) % rats[k].den_step;
819 			if (r != 0)
820 				den -= r;
821 		}
822 		diff = num - q * den;
823 		if (diff < 0)
824 			diff = -diff;
825 		if (best_num == 0 ||
826 		    diff * best_den < best_diff * den) {
827 			best_diff = diff;
828 			best_den = den;
829 			best_num = num;
830 		}
831 	}
832 	if (best_den == 0) {
833 		i->empty = 1;
834 		return -EINVAL;
835 	}
836 	t.min = div_down(best_num, best_den);
837 	t.openmin = !!(best_num % best_den);
838 
839 	result_num = best_num;
840 	result_diff = best_diff;
841 	result_den = best_den;
842 	best_num = best_den = best_diff = 0;
843 	for (k = 0; k < rats_count; ++k) {
844 		unsigned int num = rats[k].num;
845 		unsigned int den;
846 		unsigned int q = i->max;
847 		int diff;
848 		if (q == 0) {
849 			i->empty = 1;
850 			return -EINVAL;
851 		}
852 		den = div_down(num, q);
853 		if (den > rats[k].den_max)
854 			continue;
855 		if (den < rats[k].den_min)
856 			den = rats[k].den_min;
857 		else {
858 			unsigned int r;
859 			r = (den - rats[k].den_min) % rats[k].den_step;
860 			if (r != 0)
861 				den += rats[k].den_step - r;
862 		}
863 		diff = q * den - num;
864 		if (diff < 0)
865 			diff = -diff;
866 		if (best_num == 0 ||
867 		    diff * best_den < best_diff * den) {
868 			best_diff = diff;
869 			best_den = den;
870 			best_num = num;
871 		}
872 	}
873 	if (best_den == 0) {
874 		i->empty = 1;
875 		return -EINVAL;
876 	}
877 	t.max = div_up(best_num, best_den);
878 	t.openmax = !!(best_num % best_den);
879 	t.integer = 0;
880 	err = snd_interval_refine(i, &t);
881 	if (err < 0)
882 		return err;
883 
884 	if (snd_interval_single(i)) {
885 		if (best_diff * result_den < result_diff * best_den) {
886 			result_num = best_num;
887 			result_den = best_den;
888 		}
889 		if (nump)
890 			*nump = result_num;
891 		if (denp)
892 			*denp = result_den;
893 	}
894 	return err;
895 }
896 EXPORT_SYMBOL(snd_interval_ratnum);
897 
898 /**
899  * snd_interval_ratden - refine the interval value
900  * @i: interval to refine
901  * @rats_count: number of struct ratden
902  * @rats: struct ratden array
903  * @nump: pointer to store the resultant numerator
904  * @denp: pointer to store the resultant denominator
905  *
906  * Return: Positive if the value is changed, zero if it's not changed, or a
907  * negative error code.
908  */
snd_interval_ratden(struct snd_interval * i,unsigned int rats_count,const struct snd_ratden * rats,unsigned int * nump,unsigned int * denp)909 static int snd_interval_ratden(struct snd_interval *i,
910 			       unsigned int rats_count,
911 			       const struct snd_ratden *rats,
912 			       unsigned int *nump, unsigned int *denp)
913 {
914 	unsigned int best_num, best_diff, best_den;
915 	unsigned int k;
916 	struct snd_interval t;
917 	int err;
918 
919 	best_num = best_den = best_diff = 0;
920 	for (k = 0; k < rats_count; ++k) {
921 		unsigned int num;
922 		unsigned int den = rats[k].den;
923 		unsigned int q = i->min;
924 		int diff;
925 		num = mul(q, den);
926 		if (num > rats[k].num_max)
927 			continue;
928 		if (num < rats[k].num_min)
929 			num = rats[k].num_max;
930 		else {
931 			unsigned int r;
932 			r = (num - rats[k].num_min) % rats[k].num_step;
933 			if (r != 0)
934 				num += rats[k].num_step - r;
935 		}
936 		diff = num - q * den;
937 		if (best_num == 0 ||
938 		    diff * best_den < best_diff * den) {
939 			best_diff = diff;
940 			best_den = den;
941 			best_num = num;
942 		}
943 	}
944 	if (best_den == 0) {
945 		i->empty = 1;
946 		return -EINVAL;
947 	}
948 	t.min = div_down(best_num, best_den);
949 	t.openmin = !!(best_num % best_den);
950 
951 	best_num = best_den = best_diff = 0;
952 	for (k = 0; k < rats_count; ++k) {
953 		unsigned int num;
954 		unsigned int den = rats[k].den;
955 		unsigned int q = i->max;
956 		int diff;
957 		num = mul(q, den);
958 		if (num < rats[k].num_min)
959 			continue;
960 		if (num > rats[k].num_max)
961 			num = rats[k].num_max;
962 		else {
963 			unsigned int r;
964 			r = (num - rats[k].num_min) % rats[k].num_step;
965 			if (r != 0)
966 				num -= r;
967 		}
968 		diff = q * den - num;
969 		if (best_num == 0 ||
970 		    diff * best_den < best_diff * den) {
971 			best_diff = diff;
972 			best_den = den;
973 			best_num = num;
974 		}
975 	}
976 	if (best_den == 0) {
977 		i->empty = 1;
978 		return -EINVAL;
979 	}
980 	t.max = div_up(best_num, best_den);
981 	t.openmax = !!(best_num % best_den);
982 	t.integer = 0;
983 	err = snd_interval_refine(i, &t);
984 	if (err < 0)
985 		return err;
986 
987 	if (snd_interval_single(i)) {
988 		if (nump)
989 			*nump = best_num;
990 		if (denp)
991 			*denp = best_den;
992 	}
993 	return err;
994 }
995 
996 /**
997  * snd_interval_list - refine the interval value from the list
998  * @i: the interval value to refine
999  * @count: the number of elements in the list
1000  * @list: the value list
1001  * @mask: the bit-mask to evaluate
1002  *
1003  * Refines the interval value from the list.
1004  * When mask is non-zero, only the elements corresponding to bit 1 are
1005  * evaluated.
1006  *
1007  * Return: Positive if the value is changed, zero if it's not changed, or a
1008  * negative error code.
1009  */
snd_interval_list(struct snd_interval * i,unsigned int count,const unsigned int * list,unsigned int mask)1010 int snd_interval_list(struct snd_interval *i, unsigned int count,
1011 		      const unsigned int *list, unsigned int mask)
1012 {
1013         unsigned int k;
1014 	struct snd_interval list_range;
1015 
1016 	if (!count) {
1017 		i->empty = 1;
1018 		return -EINVAL;
1019 	}
1020 	snd_interval_any(&list_range);
1021 	list_range.min = UINT_MAX;
1022 	list_range.max = 0;
1023         for (k = 0; k < count; k++) {
1024 		if (mask && !(mask & (1 << k)))
1025 			continue;
1026 		if (!snd_interval_test(i, list[k]))
1027 			continue;
1028 		list_range.min = min(list_range.min, list[k]);
1029 		list_range.max = max(list_range.max, list[k]);
1030         }
1031 	return snd_interval_refine(i, &list_range);
1032 }
1033 EXPORT_SYMBOL(snd_interval_list);
1034 
1035 /**
1036  * snd_interval_ranges - refine the interval value from the list of ranges
1037  * @i: the interval value to refine
1038  * @count: the number of elements in the list of ranges
1039  * @ranges: the ranges list
1040  * @mask: the bit-mask to evaluate
1041  *
1042  * Refines the interval value from the list of ranges.
1043  * When mask is non-zero, only the elements corresponding to bit 1 are
1044  * evaluated.
1045  *
1046  * Return: Positive if the value is changed, zero if it's not changed, or a
1047  * negative error code.
1048  */
snd_interval_ranges(struct snd_interval * i,unsigned int count,const struct snd_interval * ranges,unsigned int mask)1049 int snd_interval_ranges(struct snd_interval *i, unsigned int count,
1050 			const struct snd_interval *ranges, unsigned int mask)
1051 {
1052 	unsigned int k;
1053 	struct snd_interval range_union;
1054 	struct snd_interval range;
1055 
1056 	if (!count) {
1057 		snd_interval_none(i);
1058 		return -EINVAL;
1059 	}
1060 	snd_interval_any(&range_union);
1061 	range_union.min = UINT_MAX;
1062 	range_union.max = 0;
1063 	for (k = 0; k < count; k++) {
1064 		if (mask && !(mask & (1 << k)))
1065 			continue;
1066 		snd_interval_copy(&range, &ranges[k]);
1067 		if (snd_interval_refine(&range, i) < 0)
1068 			continue;
1069 		if (snd_interval_empty(&range))
1070 			continue;
1071 
1072 		if (range.min < range_union.min) {
1073 			range_union.min = range.min;
1074 			range_union.openmin = 1;
1075 		}
1076 		if (range.min == range_union.min && !range.openmin)
1077 			range_union.openmin = 0;
1078 		if (range.max > range_union.max) {
1079 			range_union.max = range.max;
1080 			range_union.openmax = 1;
1081 		}
1082 		if (range.max == range_union.max && !range.openmax)
1083 			range_union.openmax = 0;
1084 	}
1085 	return snd_interval_refine(i, &range_union);
1086 }
1087 EXPORT_SYMBOL(snd_interval_ranges);
1088 
snd_interval_step(struct snd_interval * i,unsigned int step)1089 static int snd_interval_step(struct snd_interval *i, unsigned int step)
1090 {
1091 	unsigned int n;
1092 	int changed = 0;
1093 	n = i->min % step;
1094 	if (n != 0 || i->openmin) {
1095 		i->min += step - n;
1096 		i->openmin = 0;
1097 		changed = 1;
1098 	}
1099 	n = i->max % step;
1100 	if (n != 0 || i->openmax) {
1101 		i->max -= n;
1102 		i->openmax = 0;
1103 		changed = 1;
1104 	}
1105 	if (snd_interval_checkempty(i)) {
1106 		i->empty = 1;
1107 		return -EINVAL;
1108 	}
1109 	return changed;
1110 }
1111 
1112 /* Info constraints helpers */
1113 
1114 /**
1115  * snd_pcm_hw_rule_add - add the hw-constraint rule
1116  * @runtime: the pcm runtime instance
1117  * @cond: condition bits
1118  * @var: the variable to evaluate
1119  * @func: the evaluation function
1120  * @private: the private data pointer passed to function
1121  * @dep: the dependent variables
1122  *
1123  * Return: Zero if successful, or a negative error code on failure.
1124  */
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,...)1125 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1126 			int var,
1127 			snd_pcm_hw_rule_func_t func, void *private,
1128 			int dep, ...)
1129 {
1130 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1131 	struct snd_pcm_hw_rule *c;
1132 	unsigned int k;
1133 	va_list args;
1134 	va_start(args, dep);
1135 	if (constrs->rules_num >= constrs->rules_all) {
1136 		struct snd_pcm_hw_rule *new;
1137 		unsigned int new_rules = constrs->rules_all + 16;
1138 		new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1139 		if (!new) {
1140 			va_end(args);
1141 			return -ENOMEM;
1142 		}
1143 		if (constrs->rules) {
1144 			memcpy(new, constrs->rules,
1145 			       constrs->rules_num * sizeof(*c));
1146 			kfree(constrs->rules);
1147 		}
1148 		constrs->rules = new;
1149 		constrs->rules_all = new_rules;
1150 	}
1151 	c = &constrs->rules[constrs->rules_num];
1152 	c->cond = cond;
1153 	c->func = func;
1154 	c->var = var;
1155 	c->private = private;
1156 	k = 0;
1157 	while (1) {
1158 		if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1159 			va_end(args);
1160 			return -EINVAL;
1161 		}
1162 		c->deps[k++] = dep;
1163 		if (dep < 0)
1164 			break;
1165 		dep = va_arg(args, int);
1166 	}
1167 	constrs->rules_num++;
1168 	va_end(args);
1169 	return 0;
1170 }
1171 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1172 
1173 /**
1174  * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1175  * @runtime: PCM runtime instance
1176  * @var: hw_params variable to apply the mask
1177  * @mask: the bitmap mask
1178  *
1179  * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1180  *
1181  * Return: Zero if successful, or a negative error code on failure.
1182  */
snd_pcm_hw_constraint_mask(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var,u_int32_t mask)1183 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1184 			       u_int32_t mask)
1185 {
1186 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1187 	struct snd_mask *maskp = constrs_mask(constrs, var);
1188 	*maskp->bits &= mask;
1189 	memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1190 	if (*maskp->bits == 0)
1191 		return -EINVAL;
1192 	return 0;
1193 }
1194 
1195 /**
1196  * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1197  * @runtime: PCM runtime instance
1198  * @var: hw_params variable to apply the mask
1199  * @mask: the 64bit bitmap mask
1200  *
1201  * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1202  *
1203  * Return: Zero if successful, or a negative error code on failure.
1204  */
snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var,u_int64_t mask)1205 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1206 				 u_int64_t mask)
1207 {
1208 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1209 	struct snd_mask *maskp = constrs_mask(constrs, var);
1210 	maskp->bits[0] &= (u_int32_t)mask;
1211 	maskp->bits[1] &= (u_int32_t)(mask >> 32);
1212 	memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1213 	if (! maskp->bits[0] && ! maskp->bits[1])
1214 		return -EINVAL;
1215 	return 0;
1216 }
1217 EXPORT_SYMBOL(snd_pcm_hw_constraint_mask64);
1218 
1219 /**
1220  * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1221  * @runtime: PCM runtime instance
1222  * @var: hw_params variable to apply the integer constraint
1223  *
1224  * Apply the constraint of integer to an interval parameter.
1225  *
1226  * Return: Positive if the value is changed, zero if it's not changed, or a
1227  * negative error code.
1228  */
snd_pcm_hw_constraint_integer(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var)1229 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1230 {
1231 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1232 	return snd_interval_setinteger(constrs_interval(constrs, var));
1233 }
1234 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1235 
1236 /**
1237  * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1238  * @runtime: PCM runtime instance
1239  * @var: hw_params variable to apply the range
1240  * @min: the minimal value
1241  * @max: the maximal value
1242  *
1243  * Apply the min/max range constraint to an interval parameter.
1244  *
1245  * Return: Positive if the value is changed, zero if it's not changed, or a
1246  * negative error code.
1247  */
snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var,unsigned int min,unsigned int max)1248 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1249 				 unsigned int min, unsigned int max)
1250 {
1251 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1252 	struct snd_interval t;
1253 	t.min = min;
1254 	t.max = max;
1255 	t.openmin = t.openmax = 0;
1256 	t.integer = 0;
1257 	return snd_interval_refine(constrs_interval(constrs, var), &t);
1258 }
1259 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1260 
snd_pcm_hw_rule_list(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1261 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1262 				struct snd_pcm_hw_rule *rule)
1263 {
1264 	struct snd_pcm_hw_constraint_list *list = rule->private;
1265 	return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1266 }
1267 
1268 
1269 /**
1270  * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1271  * @runtime: PCM runtime instance
1272  * @cond: condition bits
1273  * @var: hw_params variable to apply the list constraint
1274  * @l: list
1275  *
1276  * Apply the list of constraints to an interval parameter.
1277  *
1278  * Return: Zero if successful, or a negative error code on failure.
1279  */
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)1280 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1281 			       unsigned int cond,
1282 			       snd_pcm_hw_param_t var,
1283 			       const struct snd_pcm_hw_constraint_list *l)
1284 {
1285 	return snd_pcm_hw_rule_add(runtime, cond, var,
1286 				   snd_pcm_hw_rule_list, (void *)l,
1287 				   var, -1);
1288 }
1289 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1290 
snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1291 static int snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params *params,
1292 				  struct snd_pcm_hw_rule *rule)
1293 {
1294 	struct snd_pcm_hw_constraint_ranges *r = rule->private;
1295 	return snd_interval_ranges(hw_param_interval(params, rule->var),
1296 				   r->count, r->ranges, r->mask);
1297 }
1298 
1299 
1300 /**
1301  * snd_pcm_hw_constraint_ranges - apply list of range constraints to a parameter
1302  * @runtime: PCM runtime instance
1303  * @cond: condition bits
1304  * @var: hw_params variable to apply the list of range constraints
1305  * @r: ranges
1306  *
1307  * Apply the list of range constraints to an interval parameter.
1308  *
1309  * Return: Zero if successful, or a negative error code on failure.
1310  */
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)1311 int snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime *runtime,
1312 				 unsigned int cond,
1313 				 snd_pcm_hw_param_t var,
1314 				 const struct snd_pcm_hw_constraint_ranges *r)
1315 {
1316 	return snd_pcm_hw_rule_add(runtime, cond, var,
1317 				   snd_pcm_hw_rule_ranges, (void *)r,
1318 				   var, -1);
1319 }
1320 EXPORT_SYMBOL(snd_pcm_hw_constraint_ranges);
1321 
snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1322 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1323 				   struct snd_pcm_hw_rule *rule)
1324 {
1325 	const struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1326 	unsigned int num = 0, den = 0;
1327 	int err;
1328 	err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1329 				  r->nrats, r->rats, &num, &den);
1330 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1331 		params->rate_num = num;
1332 		params->rate_den = den;
1333 	}
1334 	return err;
1335 }
1336 
1337 /**
1338  * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1339  * @runtime: PCM runtime instance
1340  * @cond: condition bits
1341  * @var: hw_params variable to apply the ratnums constraint
1342  * @r: struct snd_ratnums constriants
1343  *
1344  * Return: Zero if successful, or a negative error code on failure.
1345  */
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)1346 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1347 				  unsigned int cond,
1348 				  snd_pcm_hw_param_t var,
1349 				  const struct snd_pcm_hw_constraint_ratnums *r)
1350 {
1351 	return snd_pcm_hw_rule_add(runtime, cond, var,
1352 				   snd_pcm_hw_rule_ratnums, (void *)r,
1353 				   var, -1);
1354 }
1355 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1356 
snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1357 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1358 				   struct snd_pcm_hw_rule *rule)
1359 {
1360 	const struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1361 	unsigned int num = 0, den = 0;
1362 	int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1363 				  r->nrats, r->rats, &num, &den);
1364 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1365 		params->rate_num = num;
1366 		params->rate_den = den;
1367 	}
1368 	return err;
1369 }
1370 
1371 /**
1372  * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1373  * @runtime: PCM runtime instance
1374  * @cond: condition bits
1375  * @var: hw_params variable to apply the ratdens constraint
1376  * @r: struct snd_ratdens constriants
1377  *
1378  * Return: Zero if successful, or a negative error code on failure.
1379  */
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)1380 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1381 				  unsigned int cond,
1382 				  snd_pcm_hw_param_t var,
1383 				  const struct snd_pcm_hw_constraint_ratdens *r)
1384 {
1385 	return snd_pcm_hw_rule_add(runtime, cond, var,
1386 				   snd_pcm_hw_rule_ratdens, (void *)r,
1387 				   var, -1);
1388 }
1389 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1390 
snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1391 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1392 				  struct snd_pcm_hw_rule *rule)
1393 {
1394 	unsigned int l = (unsigned long) rule->private;
1395 	int width = l & 0xffff;
1396 	unsigned int msbits = l >> 16;
1397 	const struct snd_interval *i =
1398 		hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1399 
1400 	if (!snd_interval_single(i))
1401 		return 0;
1402 
1403 	if ((snd_interval_value(i) == width) ||
1404 	    (width == 0 && snd_interval_value(i) > msbits))
1405 		params->msbits = min_not_zero(params->msbits, msbits);
1406 
1407 	return 0;
1408 }
1409 
1410 /**
1411  * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1412  * @runtime: PCM runtime instance
1413  * @cond: condition bits
1414  * @width: sample bits width
1415  * @msbits: msbits width
1416  *
1417  * This constraint will set the number of most significant bits (msbits) if a
1418  * sample format with the specified width has been select. If width is set to 0
1419  * the msbits will be set for any sample format with a width larger than the
1420  * specified msbits.
1421  *
1422  * Return: Zero if successful, or a negative error code on failure.
1423  */
snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime * runtime,unsigned int cond,unsigned int width,unsigned int msbits)1424 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1425 				 unsigned int cond,
1426 				 unsigned int width,
1427 				 unsigned int msbits)
1428 {
1429 	unsigned long l = (msbits << 16) | width;
1430 	return snd_pcm_hw_rule_add(runtime, cond, -1,
1431 				    snd_pcm_hw_rule_msbits,
1432 				    (void*) l,
1433 				    SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1434 }
1435 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1436 
snd_pcm_hw_rule_step(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1437 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1438 				struct snd_pcm_hw_rule *rule)
1439 {
1440 	unsigned long step = (unsigned long) rule->private;
1441 	return snd_interval_step(hw_param_interval(params, rule->var), step);
1442 }
1443 
1444 /**
1445  * snd_pcm_hw_constraint_step - add a hw constraint step rule
1446  * @runtime: PCM runtime instance
1447  * @cond: condition bits
1448  * @var: hw_params variable to apply the step constraint
1449  * @step: step size
1450  *
1451  * Return: Zero if successful, or a negative error code on failure.
1452  */
snd_pcm_hw_constraint_step(struct snd_pcm_runtime * runtime,unsigned int cond,snd_pcm_hw_param_t var,unsigned long step)1453 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1454 			       unsigned int cond,
1455 			       snd_pcm_hw_param_t var,
1456 			       unsigned long step)
1457 {
1458 	return snd_pcm_hw_rule_add(runtime, cond, var,
1459 				   snd_pcm_hw_rule_step, (void *) step,
1460 				   var, -1);
1461 }
1462 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1463 
snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1464 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1465 {
1466 	static unsigned int pow2_sizes[] = {
1467 		1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1468 		1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1469 		1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1470 		1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1471 	};
1472 	return snd_interval_list(hw_param_interval(params, rule->var),
1473 				 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1474 }
1475 
1476 /**
1477  * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1478  * @runtime: PCM runtime instance
1479  * @cond: condition bits
1480  * @var: hw_params variable to apply the power-of-2 constraint
1481  *
1482  * Return: Zero if successful, or a negative error code on failure.
1483  */
snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime * runtime,unsigned int cond,snd_pcm_hw_param_t var)1484 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1485 			       unsigned int cond,
1486 			       snd_pcm_hw_param_t var)
1487 {
1488 	return snd_pcm_hw_rule_add(runtime, cond, var,
1489 				   snd_pcm_hw_rule_pow2, NULL,
1490 				   var, -1);
1491 }
1492 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1493 
snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1494 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1495 					   struct snd_pcm_hw_rule *rule)
1496 {
1497 	unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1498 	struct snd_interval *rate;
1499 
1500 	rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1501 	return snd_interval_list(rate, 1, &base_rate, 0);
1502 }
1503 
1504 /**
1505  * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1506  * @runtime: PCM runtime instance
1507  * @base_rate: the rate at which the hardware does not resample
1508  *
1509  * Return: Zero if successful, or a negative error code on failure.
1510  */
snd_pcm_hw_rule_noresample(struct snd_pcm_runtime * runtime,unsigned int base_rate)1511 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1512 			       unsigned int base_rate)
1513 {
1514 	return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1515 				   SNDRV_PCM_HW_PARAM_RATE,
1516 				   snd_pcm_hw_rule_noresample_func,
1517 				   (void *)(uintptr_t)base_rate,
1518 				   SNDRV_PCM_HW_PARAM_RATE, -1);
1519 }
1520 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1521 
_snd_pcm_hw_param_any(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1522 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1523 				  snd_pcm_hw_param_t var)
1524 {
1525 	if (hw_is_mask(var)) {
1526 		snd_mask_any(hw_param_mask(params, var));
1527 		params->cmask |= 1 << var;
1528 		params->rmask |= 1 << var;
1529 		return;
1530 	}
1531 	if (hw_is_interval(var)) {
1532 		snd_interval_any(hw_param_interval(params, var));
1533 		params->cmask |= 1 << var;
1534 		params->rmask |= 1 << var;
1535 		return;
1536 	}
1537 	snd_BUG();
1538 }
1539 
_snd_pcm_hw_params_any(struct snd_pcm_hw_params * params)1540 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1541 {
1542 	unsigned int k;
1543 	memset(params, 0, sizeof(*params));
1544 	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1545 		_snd_pcm_hw_param_any(params, k);
1546 	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1547 		_snd_pcm_hw_param_any(params, k);
1548 	params->info = ~0U;
1549 }
1550 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1551 
1552 /**
1553  * snd_pcm_hw_param_value - return @params field @var value
1554  * @params: the hw_params instance
1555  * @var: parameter to retrieve
1556  * @dir: pointer to the direction (-1,0,1) or %NULL
1557  *
1558  * Return: The value for field @var if it's fixed in configuration space
1559  * defined by @params. -%EINVAL otherwise.
1560  */
snd_pcm_hw_param_value(const struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var,int * dir)1561 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1562 			   snd_pcm_hw_param_t var, int *dir)
1563 {
1564 	if (hw_is_mask(var)) {
1565 		const struct snd_mask *mask = hw_param_mask_c(params, var);
1566 		if (!snd_mask_single(mask))
1567 			return -EINVAL;
1568 		if (dir)
1569 			*dir = 0;
1570 		return snd_mask_value(mask);
1571 	}
1572 	if (hw_is_interval(var)) {
1573 		const struct snd_interval *i = hw_param_interval_c(params, var);
1574 		if (!snd_interval_single(i))
1575 			return -EINVAL;
1576 		if (dir)
1577 			*dir = i->openmin;
1578 		return snd_interval_value(i);
1579 	}
1580 	return -EINVAL;
1581 }
1582 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1583 
_snd_pcm_hw_param_setempty(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1584 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1585 				snd_pcm_hw_param_t var)
1586 {
1587 	if (hw_is_mask(var)) {
1588 		snd_mask_none(hw_param_mask(params, var));
1589 		params->cmask |= 1 << var;
1590 		params->rmask |= 1 << var;
1591 	} else if (hw_is_interval(var)) {
1592 		snd_interval_none(hw_param_interval(params, var));
1593 		params->cmask |= 1 << var;
1594 		params->rmask |= 1 << var;
1595 	} else {
1596 		snd_BUG();
1597 	}
1598 }
1599 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1600 
_snd_pcm_hw_param_first(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1601 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1602 				   snd_pcm_hw_param_t var)
1603 {
1604 	int changed;
1605 	if (hw_is_mask(var))
1606 		changed = snd_mask_refine_first(hw_param_mask(params, var));
1607 	else if (hw_is_interval(var))
1608 		changed = snd_interval_refine_first(hw_param_interval(params, var));
1609 	else
1610 		return -EINVAL;
1611 	if (changed) {
1612 		params->cmask |= 1 << var;
1613 		params->rmask |= 1 << var;
1614 	}
1615 	return changed;
1616 }
1617 
1618 
1619 /**
1620  * snd_pcm_hw_param_first - refine config space and return minimum value
1621  * @pcm: PCM instance
1622  * @params: the hw_params instance
1623  * @var: parameter to retrieve
1624  * @dir: pointer to the direction (-1,0,1) or %NULL
1625  *
1626  * Inside configuration space defined by @params remove from @var all
1627  * values > minimum. Reduce configuration space accordingly.
1628  *
1629  * Return: The minimum, or a negative error code on failure.
1630  */
snd_pcm_hw_param_first(struct snd_pcm_substream * pcm,struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var,int * dir)1631 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1632 			   struct snd_pcm_hw_params *params,
1633 			   snd_pcm_hw_param_t var, int *dir)
1634 {
1635 	int changed = _snd_pcm_hw_param_first(params, var);
1636 	if (changed < 0)
1637 		return changed;
1638 	if (params->rmask) {
1639 		int err = snd_pcm_hw_refine(pcm, params);
1640 		if (err < 0)
1641 			return err;
1642 	}
1643 	return snd_pcm_hw_param_value(params, var, dir);
1644 }
1645 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1646 
_snd_pcm_hw_param_last(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1647 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1648 				  snd_pcm_hw_param_t var)
1649 {
1650 	int changed;
1651 	if (hw_is_mask(var))
1652 		changed = snd_mask_refine_last(hw_param_mask(params, var));
1653 	else if (hw_is_interval(var))
1654 		changed = snd_interval_refine_last(hw_param_interval(params, var));
1655 	else
1656 		return -EINVAL;
1657 	if (changed) {
1658 		params->cmask |= 1 << var;
1659 		params->rmask |= 1 << var;
1660 	}
1661 	return changed;
1662 }
1663 
1664 
1665 /**
1666  * snd_pcm_hw_param_last - refine config space and return maximum value
1667  * @pcm: PCM instance
1668  * @params: the hw_params instance
1669  * @var: parameter to retrieve
1670  * @dir: pointer to the direction (-1,0,1) or %NULL
1671  *
1672  * Inside configuration space defined by @params remove from @var all
1673  * values < maximum. Reduce configuration space accordingly.
1674  *
1675  * Return: The maximum, or a negative error code on failure.
1676  */
snd_pcm_hw_param_last(struct snd_pcm_substream * pcm,struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var,int * dir)1677 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1678 			  struct snd_pcm_hw_params *params,
1679 			  snd_pcm_hw_param_t var, int *dir)
1680 {
1681 	int changed = _snd_pcm_hw_param_last(params, var);
1682 	if (changed < 0)
1683 		return changed;
1684 	if (params->rmask) {
1685 		int err = snd_pcm_hw_refine(pcm, params);
1686 		if (err < 0)
1687 			return err;
1688 	}
1689 	return snd_pcm_hw_param_value(params, var, dir);
1690 }
1691 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1692 
snd_pcm_lib_ioctl_reset(struct snd_pcm_substream * substream,void * arg)1693 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1694 				   void *arg)
1695 {
1696 	struct snd_pcm_runtime *runtime = substream->runtime;
1697 	unsigned long flags;
1698 	snd_pcm_stream_lock_irqsave(substream, flags);
1699 	if (snd_pcm_running(substream) &&
1700 	    snd_pcm_update_hw_ptr(substream) >= 0)
1701 		runtime->status->hw_ptr %= runtime->buffer_size;
1702 	else {
1703 		runtime->status->hw_ptr = 0;
1704 		runtime->hw_ptr_wrap = 0;
1705 	}
1706 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1707 	return 0;
1708 }
1709 
snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream * substream,void * arg)1710 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1711 					  void *arg)
1712 {
1713 	struct snd_pcm_channel_info *info = arg;
1714 	struct snd_pcm_runtime *runtime = substream->runtime;
1715 	int width;
1716 	if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1717 		info->offset = -1;
1718 		return 0;
1719 	}
1720 	width = snd_pcm_format_physical_width(runtime->format);
1721 	if (width < 0)
1722 		return width;
1723 	info->offset = 0;
1724 	switch (runtime->access) {
1725 	case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1726 	case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1727 		info->first = info->channel * width;
1728 		info->step = runtime->channels * width;
1729 		break;
1730 	case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1731 	case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1732 	{
1733 		size_t size = runtime->dma_bytes / runtime->channels;
1734 		info->first = info->channel * size * 8;
1735 		info->step = width;
1736 		break;
1737 	}
1738 	default:
1739 		snd_BUG();
1740 		break;
1741 	}
1742 	return 0;
1743 }
1744 
snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream * substream,void * arg)1745 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1746 				       void *arg)
1747 {
1748 	struct snd_pcm_hw_params *params = arg;
1749 	snd_pcm_format_t format;
1750 	int channels;
1751 	ssize_t frame_size;
1752 
1753 	params->fifo_size = substream->runtime->hw.fifo_size;
1754 	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1755 		format = params_format(params);
1756 		channels = params_channels(params);
1757 		frame_size = snd_pcm_format_size(format, channels);
1758 		if (frame_size > 0)
1759 			params->fifo_size /= (unsigned)frame_size;
1760 	}
1761 	return 0;
1762 }
1763 
1764 /**
1765  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1766  * @substream: the pcm substream instance
1767  * @cmd: ioctl command
1768  * @arg: ioctl argument
1769  *
1770  * Processes the generic ioctl commands for PCM.
1771  * Can be passed as the ioctl callback for PCM ops.
1772  *
1773  * Return: Zero if successful, or a negative error code on failure.
1774  */
snd_pcm_lib_ioctl(struct snd_pcm_substream * substream,unsigned int cmd,void * arg)1775 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1776 		      unsigned int cmd, void *arg)
1777 {
1778 	switch (cmd) {
1779 	case SNDRV_PCM_IOCTL1_RESET:
1780 		return snd_pcm_lib_ioctl_reset(substream, arg);
1781 	case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1782 		return snd_pcm_lib_ioctl_channel_info(substream, arg);
1783 	case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1784 		return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1785 	}
1786 	return -ENXIO;
1787 }
1788 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1789 
1790 /**
1791  * snd_pcm_period_elapsed - update the pcm status for the next period
1792  * @substream: the pcm substream instance
1793  *
1794  * This function is called from the interrupt handler when the
1795  * PCM has processed the period size.  It will update the current
1796  * pointer, wake up sleepers, etc.
1797  *
1798  * Even if more than one periods have elapsed since the last call, you
1799  * have to call this only once.
1800  */
snd_pcm_period_elapsed(struct snd_pcm_substream * substream)1801 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1802 {
1803 	struct snd_pcm_runtime *runtime;
1804 	unsigned long flags;
1805 
1806 	if (snd_BUG_ON(!substream))
1807 		return;
1808 
1809 	snd_pcm_stream_lock_irqsave(substream, flags);
1810 	if (PCM_RUNTIME_CHECK(substream))
1811 		goto _unlock;
1812 	runtime = substream->runtime;
1813 
1814 	if (!snd_pcm_running(substream) ||
1815 	    snd_pcm_update_hw_ptr0(substream, 1) < 0)
1816 		goto _end;
1817 
1818 #ifdef CONFIG_SND_PCM_TIMER
1819 	if (substream->timer_running)
1820 		snd_timer_interrupt(substream->timer, 1);
1821 #endif
1822  _end:
1823 	kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1824  _unlock:
1825 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1826 }
1827 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1828 
1829 /*
1830  * Wait until avail_min data becomes available
1831  * Returns a negative error code if any error occurs during operation.
1832  * The available space is stored on availp.  When err = 0 and avail = 0
1833  * on the capture stream, it indicates the stream is in DRAINING state.
1834  */
wait_for_avail(struct snd_pcm_substream * substream,snd_pcm_uframes_t * availp)1835 static int wait_for_avail(struct snd_pcm_substream *substream,
1836 			      snd_pcm_uframes_t *availp)
1837 {
1838 	struct snd_pcm_runtime *runtime = substream->runtime;
1839 	int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1840 	wait_queue_entry_t wait;
1841 	int err = 0;
1842 	snd_pcm_uframes_t avail = 0;
1843 	long wait_time, tout;
1844 
1845 	init_waitqueue_entry(&wait, current);
1846 	set_current_state(TASK_INTERRUPTIBLE);
1847 	add_wait_queue(&runtime->tsleep, &wait);
1848 
1849 	if (runtime->no_period_wakeup)
1850 		wait_time = MAX_SCHEDULE_TIMEOUT;
1851 	else {
1852 		wait_time = 10;
1853 		if (runtime->rate) {
1854 			long t = runtime->period_size * 2 / runtime->rate;
1855 			wait_time = max(t, wait_time);
1856 		}
1857 		wait_time = msecs_to_jiffies(wait_time * 1000);
1858 	}
1859 
1860 	for (;;) {
1861 		if (signal_pending(current)) {
1862 			err = -ERESTARTSYS;
1863 			break;
1864 		}
1865 
1866 		/*
1867 		 * We need to check if space became available already
1868 		 * (and thus the wakeup happened already) first to close
1869 		 * the race of space already having become available.
1870 		 * This check must happen after been added to the waitqueue
1871 		 * and having current state be INTERRUPTIBLE.
1872 		 */
1873 		if (is_playback)
1874 			avail = snd_pcm_playback_avail(runtime);
1875 		else
1876 			avail = snd_pcm_capture_avail(runtime);
1877 		if (avail >= runtime->twake)
1878 			break;
1879 		snd_pcm_stream_unlock_irq(substream);
1880 
1881 		tout = schedule_timeout(wait_time);
1882 
1883 		snd_pcm_stream_lock_irq(substream);
1884 		set_current_state(TASK_INTERRUPTIBLE);
1885 		switch (runtime->status->state) {
1886 		case SNDRV_PCM_STATE_SUSPENDED:
1887 			err = -ESTRPIPE;
1888 			goto _endloop;
1889 		case SNDRV_PCM_STATE_XRUN:
1890 			err = -EPIPE;
1891 			goto _endloop;
1892 		case SNDRV_PCM_STATE_DRAINING:
1893 			if (is_playback)
1894 				err = -EPIPE;
1895 			else
1896 				avail = 0; /* indicate draining */
1897 			goto _endloop;
1898 		case SNDRV_PCM_STATE_OPEN:
1899 		case SNDRV_PCM_STATE_SETUP:
1900 		case SNDRV_PCM_STATE_DISCONNECTED:
1901 			err = -EBADFD;
1902 			goto _endloop;
1903 		case SNDRV_PCM_STATE_PAUSED:
1904 			continue;
1905 		}
1906 		if (!tout) {
1907 			pcm_dbg(substream->pcm,
1908 				"%s write error (DMA or IRQ trouble?)\n",
1909 				is_playback ? "playback" : "capture");
1910 			err = -EIO;
1911 			break;
1912 		}
1913 	}
1914  _endloop:
1915 	set_current_state(TASK_RUNNING);
1916 	remove_wait_queue(&runtime->tsleep, &wait);
1917 	*availp = avail;
1918 	return err;
1919 }
1920 
1921 typedef int (*pcm_transfer_f)(struct snd_pcm_substream *substream,
1922 			      int channel, unsigned long hwoff,
1923 			      void *buf, unsigned long bytes);
1924 
1925 typedef int (*pcm_copy_f)(struct snd_pcm_substream *, snd_pcm_uframes_t, void *,
1926 			  snd_pcm_uframes_t, snd_pcm_uframes_t, pcm_transfer_f);
1927 
1928 /* calculate the target DMA-buffer position to be written/read */
get_dma_ptr(struct snd_pcm_runtime * runtime,int channel,unsigned long hwoff)1929 static void *get_dma_ptr(struct snd_pcm_runtime *runtime,
1930 			   int channel, unsigned long hwoff)
1931 {
1932 	return runtime->dma_area + hwoff +
1933 		channel * (runtime->dma_bytes / runtime->channels);
1934 }
1935 
1936 /* 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)1937 static int default_write_copy(struct snd_pcm_substream *substream,
1938 			      int channel, unsigned long hwoff,
1939 			      void *buf, unsigned long bytes)
1940 {
1941 	if (copy_from_user(get_dma_ptr(substream->runtime, channel, hwoff),
1942 			   (void __user *)buf, bytes))
1943 		return -EFAULT;
1944 	return 0;
1945 }
1946 
1947 /* 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)1948 static int default_write_copy_kernel(struct snd_pcm_substream *substream,
1949 				     int channel, unsigned long hwoff,
1950 				     void *buf, unsigned long bytes)
1951 {
1952 	memcpy(get_dma_ptr(substream->runtime, channel, hwoff), buf, bytes);
1953 	return 0;
1954 }
1955 
1956 /* fill silence instead of copy data; called as a transfer helper
1957  * from __snd_pcm_lib_write() or directly from noninterleaved_copy() when
1958  * a NULL buffer is passed
1959  */
fill_silence(struct snd_pcm_substream * substream,int channel,unsigned long hwoff,void * buf,unsigned long bytes)1960 static int fill_silence(struct snd_pcm_substream *substream, int channel,
1961 			unsigned long hwoff, void *buf, unsigned long bytes)
1962 {
1963 	struct snd_pcm_runtime *runtime = substream->runtime;
1964 
1965 	if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
1966 		return 0;
1967 	if (substream->ops->fill_silence)
1968 		return substream->ops->fill_silence(substream, channel,
1969 						    hwoff, bytes);
1970 
1971 	snd_pcm_format_set_silence(runtime->format,
1972 				   get_dma_ptr(runtime, channel, hwoff),
1973 				   bytes_to_samples(runtime, bytes));
1974 	return 0;
1975 }
1976 
1977 /* 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)1978 static int default_read_copy(struct snd_pcm_substream *substream,
1979 			     int channel, unsigned long hwoff,
1980 			     void *buf, unsigned long bytes)
1981 {
1982 	if (copy_to_user((void __user *)buf,
1983 			 get_dma_ptr(substream->runtime, channel, hwoff),
1984 			 bytes))
1985 		return -EFAULT;
1986 	return 0;
1987 }
1988 
1989 /* 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)1990 static int default_read_copy_kernel(struct snd_pcm_substream *substream,
1991 				    int channel, unsigned long hwoff,
1992 				    void *buf, unsigned long bytes)
1993 {
1994 	memcpy(buf, get_dma_ptr(substream->runtime, channel, hwoff), bytes);
1995 	return 0;
1996 }
1997 
1998 /* call transfer function with the converted pointers and sizes;
1999  * for interleaved mode, it's one shot for all samples
2000  */
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)2001 static int interleaved_copy(struct snd_pcm_substream *substream,
2002 			    snd_pcm_uframes_t hwoff, void *data,
2003 			    snd_pcm_uframes_t off,
2004 			    snd_pcm_uframes_t frames,
2005 			    pcm_transfer_f transfer)
2006 {
2007 	struct snd_pcm_runtime *runtime = substream->runtime;
2008 
2009 	/* convert to bytes */
2010 	hwoff = frames_to_bytes(runtime, hwoff);
2011 	off = frames_to_bytes(runtime, off);
2012 	frames = frames_to_bytes(runtime, frames);
2013 	return transfer(substream, 0, hwoff, data + off, frames);
2014 }
2015 
2016 /* call transfer function with the converted pointers and sizes for each
2017  * non-interleaved channel; when buffer is NULL, silencing instead of copying
2018  */
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)2019 static int noninterleaved_copy(struct snd_pcm_substream *substream,
2020 			       snd_pcm_uframes_t hwoff, void *data,
2021 			       snd_pcm_uframes_t off,
2022 			       snd_pcm_uframes_t frames,
2023 			       pcm_transfer_f transfer)
2024 {
2025 	struct snd_pcm_runtime *runtime = substream->runtime;
2026 	int channels = runtime->channels;
2027 	void **bufs = data;
2028 	int c, err;
2029 
2030 	/* convert to bytes; note that it's not frames_to_bytes() here.
2031 	 * in non-interleaved mode, we copy for each channel, thus
2032 	 * each copy is n_samples bytes x channels = whole frames.
2033 	 */
2034 	off = samples_to_bytes(runtime, off);
2035 	frames = samples_to_bytes(runtime, frames);
2036 	hwoff = samples_to_bytes(runtime, hwoff);
2037 	for (c = 0; c < channels; ++c, ++bufs) {
2038 		if (!data || !*bufs)
2039 			err = fill_silence(substream, c, hwoff, NULL, frames);
2040 		else
2041 			err = transfer(substream, c, hwoff, *bufs + off,
2042 				       frames);
2043 		if (err < 0)
2044 			return err;
2045 	}
2046 	return 0;
2047 }
2048 
2049 /* fill silence on the given buffer position;
2050  * called from snd_pcm_playback_silence()
2051  */
fill_silence_frames(struct snd_pcm_substream * substream,snd_pcm_uframes_t off,snd_pcm_uframes_t frames)2052 static int fill_silence_frames(struct snd_pcm_substream *substream,
2053 			       snd_pcm_uframes_t off, snd_pcm_uframes_t frames)
2054 {
2055 	if (substream->runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
2056 	    substream->runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED)
2057 		return interleaved_copy(substream, off, NULL, 0, frames,
2058 					fill_silence);
2059 	else
2060 		return noninterleaved_copy(substream, off, NULL, 0, frames,
2061 					   fill_silence);
2062 }
2063 
2064 /* sanity-check for read/write methods */
pcm_sanity_check(struct snd_pcm_substream * substream)2065 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2066 {
2067 	struct snd_pcm_runtime *runtime;
2068 	if (PCM_RUNTIME_CHECK(substream))
2069 		return -ENXIO;
2070 	runtime = substream->runtime;
2071 	if (snd_BUG_ON(!substream->ops->copy_user && !runtime->dma_area))
2072 		return -EINVAL;
2073 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2074 		return -EBADFD;
2075 	return 0;
2076 }
2077 
pcm_accessible_state(struct snd_pcm_runtime * runtime)2078 static int pcm_accessible_state(struct snd_pcm_runtime *runtime)
2079 {
2080 	switch (runtime->status->state) {
2081 	case SNDRV_PCM_STATE_PREPARED:
2082 	case SNDRV_PCM_STATE_RUNNING:
2083 	case SNDRV_PCM_STATE_PAUSED:
2084 		return 0;
2085 	case SNDRV_PCM_STATE_XRUN:
2086 		return -EPIPE;
2087 	case SNDRV_PCM_STATE_SUSPENDED:
2088 		return -ESTRPIPE;
2089 	default:
2090 		return -EBADFD;
2091 	}
2092 }
2093 
2094 /* update to the given appl_ptr and call ack callback if needed;
2095  * when an error is returned, take back to the original value
2096  */
pcm_lib_apply_appl_ptr(struct snd_pcm_substream * substream,snd_pcm_uframes_t appl_ptr)2097 int pcm_lib_apply_appl_ptr(struct snd_pcm_substream *substream,
2098 			   snd_pcm_uframes_t appl_ptr)
2099 {
2100 	struct snd_pcm_runtime *runtime = substream->runtime;
2101 	snd_pcm_uframes_t old_appl_ptr = runtime->control->appl_ptr;
2102 	int ret;
2103 
2104 	if (old_appl_ptr == appl_ptr)
2105 		return 0;
2106 
2107 	runtime->control->appl_ptr = appl_ptr;
2108 	if (substream->ops->ack) {
2109 		ret = substream->ops->ack(substream);
2110 		if (ret < 0) {
2111 			runtime->control->appl_ptr = old_appl_ptr;
2112 			return ret;
2113 		}
2114 	}
2115 
2116 	trace_applptr(substream, old_appl_ptr, appl_ptr);
2117 
2118 	return 0;
2119 }
2120 
2121 /* 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)2122 snd_pcm_sframes_t __snd_pcm_lib_xfer(struct snd_pcm_substream *substream,
2123 				     void *data, bool interleaved,
2124 				     snd_pcm_uframes_t size, bool in_kernel)
2125 {
2126 	struct snd_pcm_runtime *runtime = substream->runtime;
2127 	snd_pcm_uframes_t xfer = 0;
2128 	snd_pcm_uframes_t offset = 0;
2129 	snd_pcm_uframes_t avail;
2130 	pcm_copy_f writer;
2131 	pcm_transfer_f transfer;
2132 	bool nonblock;
2133 	bool is_playback;
2134 	int err;
2135 
2136 	err = pcm_sanity_check(substream);
2137 	if (err < 0)
2138 		return err;
2139 
2140 	is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
2141 	if (interleaved) {
2142 		if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2143 		    runtime->channels > 1)
2144 			return -EINVAL;
2145 		writer = interleaved_copy;
2146 	} else {
2147 		if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2148 			return -EINVAL;
2149 		writer = noninterleaved_copy;
2150 	}
2151 
2152 	if (!data) {
2153 		if (is_playback)
2154 			transfer = fill_silence;
2155 		else
2156 			return -EINVAL;
2157 	} else if (in_kernel) {
2158 		if (substream->ops->copy_kernel)
2159 			transfer = substream->ops->copy_kernel;
2160 		else
2161 			transfer = is_playback ?
2162 				default_write_copy_kernel : default_read_copy_kernel;
2163 	} else {
2164 		if (substream->ops->copy_user)
2165 			transfer = (pcm_transfer_f)substream->ops->copy_user;
2166 		else
2167 			transfer = is_playback ?
2168 				default_write_copy : default_read_copy;
2169 	}
2170 
2171 	if (size == 0)
2172 		return 0;
2173 
2174 	nonblock = !!(substream->f_flags & O_NONBLOCK);
2175 
2176 	snd_pcm_stream_lock_irq(substream);
2177 	err = pcm_accessible_state(runtime);
2178 	if (err < 0)
2179 		goto _end_unlock;
2180 
2181 	if (!is_playback &&
2182 	    runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2183 	    size >= runtime->start_threshold) {
2184 		err = snd_pcm_start(substream);
2185 		if (err < 0)
2186 			goto _end_unlock;
2187 	}
2188 
2189 	runtime->twake = runtime->control->avail_min ? : 1;
2190 	if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2191 		snd_pcm_update_hw_ptr(substream);
2192 	if (is_playback)
2193 		avail = snd_pcm_playback_avail(runtime);
2194 	else
2195 		avail = snd_pcm_capture_avail(runtime);
2196 	while (size > 0) {
2197 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2198 		snd_pcm_uframes_t cont;
2199 		if (!avail) {
2200 			if (!is_playback &&
2201 			    runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
2202 				snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2203 				goto _end_unlock;
2204 			}
2205 			if (nonblock) {
2206 				err = -EAGAIN;
2207 				goto _end_unlock;
2208 			}
2209 			runtime->twake = min_t(snd_pcm_uframes_t, size,
2210 					runtime->control->avail_min ? : 1);
2211 			err = wait_for_avail(substream, &avail);
2212 			if (err < 0)
2213 				goto _end_unlock;
2214 			if (!avail)
2215 				continue; /* draining */
2216 		}
2217 		frames = size > avail ? avail : size;
2218 		appl_ptr = READ_ONCE(runtime->control->appl_ptr);
2219 		appl_ofs = appl_ptr % runtime->buffer_size;
2220 		cont = runtime->buffer_size - appl_ofs;
2221 		if (frames > cont)
2222 			frames = cont;
2223 		if (snd_BUG_ON(!frames)) {
2224 			runtime->twake = 0;
2225 			snd_pcm_stream_unlock_irq(substream);
2226 			return -EINVAL;
2227 		}
2228 		snd_pcm_stream_unlock_irq(substream);
2229 		err = writer(substream, appl_ofs, data, offset, frames,
2230 			     transfer);
2231 		snd_pcm_stream_lock_irq(substream);
2232 		if (err < 0)
2233 			goto _end_unlock;
2234 		err = pcm_accessible_state(runtime);
2235 		if (err < 0)
2236 			goto _end_unlock;
2237 		appl_ptr += frames;
2238 		if (appl_ptr >= runtime->boundary)
2239 			appl_ptr -= runtime->boundary;
2240 		err = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2241 		if (err < 0)
2242 			goto _end_unlock;
2243 
2244 		offset += frames;
2245 		size -= frames;
2246 		xfer += frames;
2247 		avail -= frames;
2248 		if (is_playback &&
2249 		    runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2250 		    snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2251 			err = snd_pcm_start(substream);
2252 			if (err < 0)
2253 				goto _end_unlock;
2254 		}
2255 	}
2256  _end_unlock:
2257 	runtime->twake = 0;
2258 	if (xfer > 0 && err >= 0)
2259 		snd_pcm_update_state(substream, runtime);
2260 	snd_pcm_stream_unlock_irq(substream);
2261 	return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2262 }
2263 EXPORT_SYMBOL(__snd_pcm_lib_xfer);
2264 
2265 /*
2266  * standard channel mapping helpers
2267  */
2268 
2269 /* default channel maps for multi-channel playbacks, up to 8 channels */
2270 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2271 	{ .channels = 1,
2272 	  .map = { SNDRV_CHMAP_MONO } },
2273 	{ .channels = 2,
2274 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2275 	{ .channels = 4,
2276 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2277 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2278 	{ .channels = 6,
2279 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2280 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2281 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2282 	{ .channels = 8,
2283 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2284 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2285 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2286 		   SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2287 	{ }
2288 };
2289 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2290 
2291 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2292 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2293 	{ .channels = 1,
2294 	  .map = { SNDRV_CHMAP_MONO } },
2295 	{ .channels = 2,
2296 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2297 	{ .channels = 4,
2298 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2299 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2300 	{ .channels = 6,
2301 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2302 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2303 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2304 	{ .channels = 8,
2305 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2306 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2307 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2308 		   SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2309 	{ }
2310 };
2311 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2312 
valid_chmap_channels(const struct snd_pcm_chmap * info,int ch)2313 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2314 {
2315 	if (ch > info->max_channels)
2316 		return false;
2317 	return !info->channel_mask || (info->channel_mask & (1U << ch));
2318 }
2319 
pcm_chmap_ctl_info(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_info * uinfo)2320 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2321 			      struct snd_ctl_elem_info *uinfo)
2322 {
2323 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2324 
2325 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2326 	uinfo->count = 0;
2327 	uinfo->count = info->max_channels;
2328 	uinfo->value.integer.min = 0;
2329 	uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2330 	return 0;
2331 }
2332 
2333 /* get callback for channel map ctl element
2334  * stores the channel position firstly matching with the current channels
2335  */
pcm_chmap_ctl_get(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_value * ucontrol)2336 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2337 			     struct snd_ctl_elem_value *ucontrol)
2338 {
2339 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2340 	unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2341 	struct snd_pcm_substream *substream;
2342 	const struct snd_pcm_chmap_elem *map;
2343 
2344 	if (!info->chmap)
2345 		return -EINVAL;
2346 	substream = snd_pcm_chmap_substream(info, idx);
2347 	if (!substream)
2348 		return -ENODEV;
2349 	memset(ucontrol->value.integer.value, 0,
2350 	       sizeof(ucontrol->value.integer.value));
2351 	if (!substream->runtime)
2352 		return 0; /* no channels set */
2353 	for (map = info->chmap; map->channels; map++) {
2354 		int i;
2355 		if (map->channels == substream->runtime->channels &&
2356 		    valid_chmap_channels(info, map->channels)) {
2357 			for (i = 0; i < map->channels; i++)
2358 				ucontrol->value.integer.value[i] = map->map[i];
2359 			return 0;
2360 		}
2361 	}
2362 	return -EINVAL;
2363 }
2364 
2365 /* tlv callback for channel map ctl element
2366  * expands the pre-defined channel maps in a form of TLV
2367  */
pcm_chmap_ctl_tlv(struct snd_kcontrol * kcontrol,int op_flag,unsigned int size,unsigned int __user * tlv)2368 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2369 			     unsigned int size, unsigned int __user *tlv)
2370 {
2371 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2372 	const struct snd_pcm_chmap_elem *map;
2373 	unsigned int __user *dst;
2374 	int c, count = 0;
2375 
2376 	if (!info->chmap)
2377 		return -EINVAL;
2378 	if (size < 8)
2379 		return -ENOMEM;
2380 	if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2381 		return -EFAULT;
2382 	size -= 8;
2383 	dst = tlv + 2;
2384 	for (map = info->chmap; map->channels; map++) {
2385 		int chs_bytes = map->channels * 4;
2386 		if (!valid_chmap_channels(info, map->channels))
2387 			continue;
2388 		if (size < 8)
2389 			return -ENOMEM;
2390 		if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2391 		    put_user(chs_bytes, dst + 1))
2392 			return -EFAULT;
2393 		dst += 2;
2394 		size -= 8;
2395 		count += 8;
2396 		if (size < chs_bytes)
2397 			return -ENOMEM;
2398 		size -= chs_bytes;
2399 		count += chs_bytes;
2400 		for (c = 0; c < map->channels; c++) {
2401 			if (put_user(map->map[c], dst))
2402 				return -EFAULT;
2403 			dst++;
2404 		}
2405 	}
2406 	if (put_user(count, tlv + 1))
2407 		return -EFAULT;
2408 	return 0;
2409 }
2410 
pcm_chmap_ctl_private_free(struct snd_kcontrol * kcontrol)2411 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2412 {
2413 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2414 	info->pcm->streams[info->stream].chmap_kctl = NULL;
2415 	kfree(info);
2416 }
2417 
2418 /**
2419  * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2420  * @pcm: the assigned PCM instance
2421  * @stream: stream direction
2422  * @chmap: channel map elements (for query)
2423  * @max_channels: the max number of channels for the stream
2424  * @private_value: the value passed to each kcontrol's private_value field
2425  * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2426  *
2427  * Create channel-mapping control elements assigned to the given PCM stream(s).
2428  * Return: Zero if successful, or a negative error value.
2429  */
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)2430 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2431 			   const struct snd_pcm_chmap_elem *chmap,
2432 			   int max_channels,
2433 			   unsigned long private_value,
2434 			   struct snd_pcm_chmap **info_ret)
2435 {
2436 	struct snd_pcm_chmap *info;
2437 	struct snd_kcontrol_new knew = {
2438 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
2439 		.access = SNDRV_CTL_ELEM_ACCESS_READ |
2440 			SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2441 			SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2442 		.info = pcm_chmap_ctl_info,
2443 		.get = pcm_chmap_ctl_get,
2444 		.tlv.c = pcm_chmap_ctl_tlv,
2445 	};
2446 	int err;
2447 
2448 	if (WARN_ON(pcm->streams[stream].chmap_kctl))
2449 		return -EBUSY;
2450 	info = kzalloc(sizeof(*info), GFP_KERNEL);
2451 	if (!info)
2452 		return -ENOMEM;
2453 	info->pcm = pcm;
2454 	info->stream = stream;
2455 	info->chmap = chmap;
2456 	info->max_channels = max_channels;
2457 	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2458 		knew.name = "Playback Channel Map";
2459 	else
2460 		knew.name = "Capture Channel Map";
2461 	knew.device = pcm->device;
2462 	knew.count = pcm->streams[stream].substream_count;
2463 	knew.private_value = private_value;
2464 	info->kctl = snd_ctl_new1(&knew, info);
2465 	if (!info->kctl) {
2466 		kfree(info);
2467 		return -ENOMEM;
2468 	}
2469 	info->kctl->private_free = pcm_chmap_ctl_private_free;
2470 	err = snd_ctl_add(pcm->card, info->kctl);
2471 	if (err < 0)
2472 		return err;
2473 	pcm->streams[stream].chmap_kctl = info->kctl;
2474 	if (info_ret)
2475 		*info_ret = info;
2476 	return 0;
2477 }
2478 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);
2479