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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/time.h>
25 #include <linux/math64.h>
26 #include <linux/export.h>
27 #include <sound/core.h>
28 #include <sound/control.h>
29 #include <sound/tlv.h>
30 #include <sound/info.h>
31 #include <sound/pcm.h>
32 #include <sound/pcm_params.h>
33 #include <sound/timer.h>
34 
35 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
36 #define CREATE_TRACE_POINTS
37 #include "pcm_trace.h"
38 #else
39 #define trace_hwptr(substream, pos, in_interrupt)
40 #define trace_xrun(substream)
41 #define trace_hw_ptr_error(substream, reason)
42 #endif
43 
44 /*
45  * fill ring buffer with silence
46  * runtime->silence_start: starting pointer to silence area
47  * runtime->silence_filled: size filled with silence
48  * runtime->silence_threshold: threshold from application
49  * runtime->silence_size: maximal size from application
50  *
51  * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
52  */
snd_pcm_playback_silence(struct snd_pcm_substream * substream,snd_pcm_uframes_t new_hw_ptr)53 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
54 {
55 	struct snd_pcm_runtime *runtime = substream->runtime;
56 	snd_pcm_uframes_t frames, ofs, transfer;
57 
58 	if (runtime->silence_size < runtime->boundary) {
59 		snd_pcm_sframes_t noise_dist, n;
60 		if (runtime->silence_start != runtime->control->appl_ptr) {
61 			n = runtime->control->appl_ptr - runtime->silence_start;
62 			if (n < 0)
63 				n += runtime->boundary;
64 			if ((snd_pcm_uframes_t)n < runtime->silence_filled)
65 				runtime->silence_filled -= n;
66 			else
67 				runtime->silence_filled = 0;
68 			runtime->silence_start = runtime->control->appl_ptr;
69 		}
70 		if (runtime->silence_filled >= runtime->buffer_size)
71 			return;
72 		noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
73 		if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
74 			return;
75 		frames = runtime->silence_threshold - noise_dist;
76 		if (frames > runtime->silence_size)
77 			frames = runtime->silence_size;
78 	} else {
79 		if (new_hw_ptr == ULONG_MAX) {	/* initialization */
80 			snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
81 			if (avail > runtime->buffer_size)
82 				avail = runtime->buffer_size;
83 			runtime->silence_filled = avail > 0 ? avail : 0;
84 			runtime->silence_start = (runtime->status->hw_ptr +
85 						  runtime->silence_filled) %
86 						 runtime->boundary;
87 		} else {
88 			ofs = runtime->status->hw_ptr;
89 			frames = new_hw_ptr - ofs;
90 			if ((snd_pcm_sframes_t)frames < 0)
91 				frames += runtime->boundary;
92 			runtime->silence_filled -= frames;
93 			if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
94 				runtime->silence_filled = 0;
95 				runtime->silence_start = new_hw_ptr;
96 			} else {
97 				runtime->silence_start = ofs;
98 			}
99 		}
100 		frames = runtime->buffer_size - runtime->silence_filled;
101 	}
102 	if (snd_BUG_ON(frames > runtime->buffer_size))
103 		return;
104 	if (frames == 0)
105 		return;
106 	ofs = runtime->silence_start % runtime->buffer_size;
107 	while (frames > 0) {
108 		transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
109 		if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
110 		    runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
111 			if (substream->ops->silence) {
112 				int err;
113 				err = substream->ops->silence(substream, -1, ofs, transfer);
114 				snd_BUG_ON(err < 0);
115 			} else {
116 				char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
117 				snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
118 			}
119 		} else {
120 			unsigned int c;
121 			unsigned int channels = runtime->channels;
122 			if (substream->ops->silence) {
123 				for (c = 0; c < channels; ++c) {
124 					int err;
125 					err = substream->ops->silence(substream, c, ofs, transfer);
126 					snd_BUG_ON(err < 0);
127 				}
128 			} else {
129 				size_t dma_csize = runtime->dma_bytes / channels;
130 				for (c = 0; c < channels; ++c) {
131 					char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
132 					snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
133 				}
134 			}
135 		}
136 		runtime->silence_filled += transfer;
137 		frames -= transfer;
138 		ofs = 0;
139 	}
140 }
141 
142 #ifdef CONFIG_SND_DEBUG
snd_pcm_debug_name(struct snd_pcm_substream * substream,char * name,size_t len)143 void snd_pcm_debug_name(struct snd_pcm_substream *substream,
144 			   char *name, size_t len)
145 {
146 	snprintf(name, len, "pcmC%dD%d%c:%d",
147 		 substream->pcm->card->number,
148 		 substream->pcm->device,
149 		 substream->stream ? 'c' : 'p',
150 		 substream->number);
151 }
152 EXPORT_SYMBOL(snd_pcm_debug_name);
153 #endif
154 
155 #define XRUN_DEBUG_BASIC	(1<<0)
156 #define XRUN_DEBUG_STACK	(1<<1)	/* dump also stack */
157 #define XRUN_DEBUG_JIFFIESCHECK	(1<<2)	/* do jiffies check */
158 
159 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
160 
161 #define xrun_debug(substream, mask) \
162 			((substream)->pstr->xrun_debug & (mask))
163 #else
164 #define xrun_debug(substream, mask)	0
165 #endif
166 
167 #define dump_stack_on_xrun(substream) do {			\
168 		if (xrun_debug(substream, XRUN_DEBUG_STACK))	\
169 			dump_stack();				\
170 	} while (0)
171 
xrun(struct snd_pcm_substream * substream)172 static void xrun(struct snd_pcm_substream *substream)
173 {
174 	struct snd_pcm_runtime *runtime = substream->runtime;
175 
176 	trace_xrun(substream);
177 	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
178 		snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
179 	snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
180 	if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
181 		char name[16];
182 		snd_pcm_debug_name(substream, name, sizeof(name));
183 		pcm_warn(substream->pcm, "XRUN: %s\n", name);
184 		dump_stack_on_xrun(substream);
185 	}
186 }
187 
188 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
189 #define hw_ptr_error(substream, in_interrupt, reason, fmt, args...)	\
190 	do {								\
191 		trace_hw_ptr_error(substream, reason);	\
192 		if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {		\
193 			pr_err_ratelimited("ALSA: PCM: [%c] " reason ": " fmt, \
194 					   (in_interrupt) ? 'Q' : 'P', ##args);	\
195 			dump_stack_on_xrun(substream);			\
196 		}							\
197 	} while (0)
198 
199 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
200 
201 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
202 
203 #endif
204 
snd_pcm_update_state(struct snd_pcm_substream * substream,struct snd_pcm_runtime * runtime)205 int snd_pcm_update_state(struct snd_pcm_substream *substream,
206 			 struct snd_pcm_runtime *runtime)
207 {
208 	snd_pcm_uframes_t avail;
209 
210 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
211 		avail = snd_pcm_playback_avail(runtime);
212 	else
213 		avail = snd_pcm_capture_avail(runtime);
214 	if (avail > runtime->avail_max)
215 		runtime->avail_max = avail;
216 	if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
217 		if (avail >= runtime->buffer_size) {
218 			snd_pcm_drain_done(substream);
219 			return -EPIPE;
220 		}
221 	} else {
222 		if (avail >= runtime->stop_threshold) {
223 			xrun(substream);
224 			return -EPIPE;
225 		}
226 	}
227 	if (runtime->twake) {
228 		if (avail >= runtime->twake)
229 			wake_up(&runtime->tsleep);
230 	} else if (avail >= runtime->control->avail_min)
231 		wake_up(&runtime->sleep);
232 	return 0;
233 }
234 
update_audio_tstamp(struct snd_pcm_substream * substream,struct timespec * curr_tstamp,struct timespec * audio_tstamp)235 static void update_audio_tstamp(struct snd_pcm_substream *substream,
236 				struct timespec *curr_tstamp,
237 				struct timespec *audio_tstamp)
238 {
239 	struct snd_pcm_runtime *runtime = substream->runtime;
240 	u64 audio_frames, audio_nsecs;
241 	struct timespec driver_tstamp;
242 
243 	if (runtime->tstamp_mode != SNDRV_PCM_TSTAMP_ENABLE)
244 		return;
245 
246 	if (!(substream->ops->get_time_info) ||
247 		(runtime->audio_tstamp_report.actual_type ==
248 			SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
249 
250 		/*
251 		 * provide audio timestamp derived from pointer position
252 		 * add delay only if requested
253 		 */
254 
255 		audio_frames = runtime->hw_ptr_wrap + runtime->status->hw_ptr;
256 
257 		if (runtime->audio_tstamp_config.report_delay) {
258 			if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
259 				audio_frames -=  runtime->delay;
260 			else
261 				audio_frames +=  runtime->delay;
262 		}
263 		audio_nsecs = div_u64(audio_frames * 1000000000LL,
264 				runtime->rate);
265 		*audio_tstamp = ns_to_timespec(audio_nsecs);
266 	}
267 	if (!timespec_equal(&runtime->status->audio_tstamp, audio_tstamp)) {
268 		runtime->status->audio_tstamp = *audio_tstamp;
269 		runtime->status->tstamp = *curr_tstamp;
270 	}
271 
272 	/*
273 	 * re-take a driver timestamp to let apps detect if the reference tstamp
274 	 * read by low-level hardware was provided with a delay
275 	 */
276 	snd_pcm_gettime(substream->runtime, (struct timespec *)&driver_tstamp);
277 	runtime->driver_tstamp = driver_tstamp;
278 }
279 
snd_pcm_update_hw_ptr0(struct snd_pcm_substream * substream,unsigned int in_interrupt)280 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
281 				  unsigned int in_interrupt)
282 {
283 	struct snd_pcm_runtime *runtime = substream->runtime;
284 	snd_pcm_uframes_t pos;
285 	snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
286 	snd_pcm_sframes_t hdelta, delta;
287 	unsigned long jdelta;
288 	unsigned long curr_jiffies;
289 	struct timespec curr_tstamp;
290 	struct timespec audio_tstamp;
291 	int crossed_boundary = 0;
292 
293 	old_hw_ptr = runtime->status->hw_ptr;
294 
295 	/*
296 	 * group pointer, time and jiffies reads to allow for more
297 	 * accurate correlations/corrections.
298 	 * The values are stored at the end of this routine after
299 	 * corrections for hw_ptr position
300 	 */
301 	pos = substream->ops->pointer(substream);
302 	curr_jiffies = jiffies;
303 	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
304 		if ((substream->ops->get_time_info) &&
305 			(runtime->audio_tstamp_config.type_requested != SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
306 			substream->ops->get_time_info(substream, &curr_tstamp,
307 						&audio_tstamp,
308 						&runtime->audio_tstamp_config,
309 						&runtime->audio_tstamp_report);
310 
311 			/* re-test in case tstamp type is not supported in hardware and was demoted to DEFAULT */
312 			if (runtime->audio_tstamp_report.actual_type == SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)
313 				snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
314 		} else
315 			snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
316 	}
317 
318 	if (pos == SNDRV_PCM_POS_XRUN) {
319 		xrun(substream);
320 		return -EPIPE;
321 	}
322 	if (pos >= runtime->buffer_size) {
323 		if (printk_ratelimit()) {
324 			char name[16];
325 			snd_pcm_debug_name(substream, name, sizeof(name));
326 			pcm_err(substream->pcm,
327 				"invalid position: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
328 				name, pos, runtime->buffer_size,
329 				runtime->period_size);
330 		}
331 		pos = 0;
332 	}
333 	pos -= pos % runtime->min_align;
334 	trace_hwptr(substream, pos, in_interrupt);
335 	hw_base = runtime->hw_ptr_base;
336 	new_hw_ptr = hw_base + pos;
337 	if (in_interrupt) {
338 		/* we know that one period was processed */
339 		/* delta = "expected next hw_ptr" for in_interrupt != 0 */
340 		delta = runtime->hw_ptr_interrupt + runtime->period_size;
341 		if (delta > new_hw_ptr) {
342 			/* check for double acknowledged interrupts */
343 			hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
344 			if (hdelta > runtime->hw_ptr_buffer_jiffies/2 + 1) {
345 				hw_base += runtime->buffer_size;
346 				if (hw_base >= runtime->boundary) {
347 					hw_base = 0;
348 					crossed_boundary++;
349 				}
350 				new_hw_ptr = hw_base + pos;
351 				goto __delta;
352 			}
353 		}
354 	}
355 	/* new_hw_ptr might be lower than old_hw_ptr in case when */
356 	/* pointer crosses the end of the ring buffer */
357 	if (new_hw_ptr < old_hw_ptr) {
358 		hw_base += runtime->buffer_size;
359 		if (hw_base >= runtime->boundary) {
360 			hw_base = 0;
361 			crossed_boundary++;
362 		}
363 		new_hw_ptr = hw_base + pos;
364 	}
365       __delta:
366 	delta = new_hw_ptr - old_hw_ptr;
367 	if (delta < 0)
368 		delta += runtime->boundary;
369 
370 	if (runtime->no_period_wakeup) {
371 		snd_pcm_sframes_t xrun_threshold;
372 		/*
373 		 * Without regular period interrupts, we have to check
374 		 * the elapsed time to detect xruns.
375 		 */
376 		jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
377 		if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
378 			goto no_delta_check;
379 		hdelta = jdelta - delta * HZ / runtime->rate;
380 		xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
381 		while (hdelta > xrun_threshold) {
382 			delta += runtime->buffer_size;
383 			hw_base += runtime->buffer_size;
384 			if (hw_base >= runtime->boundary) {
385 				hw_base = 0;
386 				crossed_boundary++;
387 			}
388 			new_hw_ptr = hw_base + pos;
389 			hdelta -= runtime->hw_ptr_buffer_jiffies;
390 		}
391 		goto no_delta_check;
392 	}
393 
394 	/* something must be really wrong */
395 	if (delta >= runtime->buffer_size + runtime->period_size) {
396 		hw_ptr_error(substream, in_interrupt, "Unexpected hw_ptr",
397 			     "(stream=%i, pos=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
398 			     substream->stream, (long)pos,
399 			     (long)new_hw_ptr, (long)old_hw_ptr);
400 		return 0;
401 	}
402 
403 	/* Do jiffies check only in xrun_debug mode */
404 	if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
405 		goto no_jiffies_check;
406 
407 	/* Skip the jiffies check for hardwares with BATCH flag.
408 	 * Such hardware usually just increases the position at each IRQ,
409 	 * thus it can't give any strange position.
410 	 */
411 	if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
412 		goto no_jiffies_check;
413 	hdelta = delta;
414 	if (hdelta < runtime->delay)
415 		goto no_jiffies_check;
416 	hdelta -= runtime->delay;
417 	jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
418 	if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
419 		delta = jdelta /
420 			(((runtime->period_size * HZ) / runtime->rate)
421 								+ HZ/100);
422 		/* move new_hw_ptr according jiffies not pos variable */
423 		new_hw_ptr = old_hw_ptr;
424 		hw_base = delta;
425 		/* use loop to avoid checks for delta overflows */
426 		/* the delta value is small or zero in most cases */
427 		while (delta > 0) {
428 			new_hw_ptr += runtime->period_size;
429 			if (new_hw_ptr >= runtime->boundary) {
430 				new_hw_ptr -= runtime->boundary;
431 				crossed_boundary--;
432 			}
433 			delta--;
434 		}
435 		/* align hw_base to buffer_size */
436 		hw_ptr_error(substream, in_interrupt, "hw_ptr skipping",
437 			     "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
438 			     (long)pos, (long)hdelta,
439 			     (long)runtime->period_size, jdelta,
440 			     ((hdelta * HZ) / runtime->rate), hw_base,
441 			     (unsigned long)old_hw_ptr,
442 			     (unsigned long)new_hw_ptr);
443 		/* reset values to proper state */
444 		delta = 0;
445 		hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
446 	}
447  no_jiffies_check:
448 	if (delta > runtime->period_size + runtime->period_size / 2) {
449 		hw_ptr_error(substream, in_interrupt,
450 			     "Lost interrupts?",
451 			     "(stream=%i, delta=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
452 			     substream->stream, (long)delta,
453 			     (long)new_hw_ptr,
454 			     (long)old_hw_ptr);
455 	}
456 
457  no_delta_check:
458 	if (runtime->status->hw_ptr == new_hw_ptr) {
459 		runtime->hw_ptr_jiffies = curr_jiffies;
460 		update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
461 		return 0;
462 	}
463 
464 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
465 	    runtime->silence_size > 0)
466 		snd_pcm_playback_silence(substream, new_hw_ptr);
467 
468 	if (in_interrupt) {
469 		delta = new_hw_ptr - runtime->hw_ptr_interrupt;
470 		if (delta < 0)
471 			delta += runtime->boundary;
472 		delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
473 		runtime->hw_ptr_interrupt += delta;
474 		if (runtime->hw_ptr_interrupt >= runtime->boundary)
475 			runtime->hw_ptr_interrupt -= runtime->boundary;
476 	}
477 	runtime->hw_ptr_base = hw_base;
478 	runtime->status->hw_ptr = new_hw_ptr;
479 	runtime->hw_ptr_jiffies = curr_jiffies;
480 	if (crossed_boundary) {
481 		snd_BUG_ON(crossed_boundary != 1);
482 		runtime->hw_ptr_wrap += runtime->boundary;
483 	}
484 
485 	update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
486 
487 	return snd_pcm_update_state(substream, runtime);
488 }
489 
490 /* CAUTION: call it with irq disabled */
snd_pcm_update_hw_ptr(struct snd_pcm_substream * substream)491 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
492 {
493 	return snd_pcm_update_hw_ptr0(substream, 0);
494 }
495 
496 /**
497  * snd_pcm_set_ops - set the PCM operators
498  * @pcm: the pcm instance
499  * @direction: stream direction, SNDRV_PCM_STREAM_XXX
500  * @ops: the operator table
501  *
502  * Sets the given PCM operators to the pcm instance.
503  */
snd_pcm_set_ops(struct snd_pcm * pcm,int direction,const struct snd_pcm_ops * ops)504 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
505 		     const struct snd_pcm_ops *ops)
506 {
507 	struct snd_pcm_str *stream = &pcm->streams[direction];
508 	struct snd_pcm_substream *substream;
509 
510 	for (substream = stream->substream; substream != NULL; substream = substream->next)
511 		substream->ops = ops;
512 }
513 
514 EXPORT_SYMBOL(snd_pcm_set_ops);
515 
516 /**
517  * snd_pcm_sync - set the PCM sync id
518  * @substream: the pcm substream
519  *
520  * Sets the PCM sync identifier for the card.
521  */
snd_pcm_set_sync(struct snd_pcm_substream * substream)522 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
523 {
524 	struct snd_pcm_runtime *runtime = substream->runtime;
525 
526 	runtime->sync.id32[0] = substream->pcm->card->number;
527 	runtime->sync.id32[1] = -1;
528 	runtime->sync.id32[2] = -1;
529 	runtime->sync.id32[3] = -1;
530 }
531 
532 EXPORT_SYMBOL(snd_pcm_set_sync);
533 
534 /*
535  *  Standard ioctl routine
536  */
537 
div32(unsigned int a,unsigned int b,unsigned int * r)538 static inline unsigned int div32(unsigned int a, unsigned int b,
539 				 unsigned int *r)
540 {
541 	if (b == 0) {
542 		*r = 0;
543 		return UINT_MAX;
544 	}
545 	*r = a % b;
546 	return a / b;
547 }
548 
div_down(unsigned int a,unsigned int b)549 static inline unsigned int div_down(unsigned int a, unsigned int b)
550 {
551 	if (b == 0)
552 		return UINT_MAX;
553 	return a / b;
554 }
555 
div_up(unsigned int a,unsigned int b)556 static inline unsigned int div_up(unsigned int a, unsigned int b)
557 {
558 	unsigned int r;
559 	unsigned int q;
560 	if (b == 0)
561 		return UINT_MAX;
562 	q = div32(a, b, &r);
563 	if (r)
564 		++q;
565 	return q;
566 }
567 
mul(unsigned int a,unsigned int b)568 static inline unsigned int mul(unsigned int a, unsigned int b)
569 {
570 	if (a == 0)
571 		return 0;
572 	if (div_down(UINT_MAX, a) < b)
573 		return UINT_MAX;
574 	return a * b;
575 }
576 
muldiv32(unsigned int a,unsigned int b,unsigned int c,unsigned int * r)577 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
578 				    unsigned int c, unsigned int *r)
579 {
580 	u_int64_t n = (u_int64_t) a * b;
581 	if (c == 0) {
582 		*r = 0;
583 		return UINT_MAX;
584 	}
585 	n = div_u64_rem(n, c, r);
586 	if (n >= UINT_MAX) {
587 		*r = 0;
588 		return UINT_MAX;
589 	}
590 	return n;
591 }
592 
593 /**
594  * snd_interval_refine - refine the interval value of configurator
595  * @i: the interval value to refine
596  * @v: the interval value to refer to
597  *
598  * Refines the interval value with the reference value.
599  * The interval is changed to the range satisfying both intervals.
600  * The interval status (min, max, integer, etc.) are evaluated.
601  *
602  * Return: Positive if the value is changed, zero if it's not changed, or a
603  * negative error code.
604  */
snd_interval_refine(struct snd_interval * i,const struct snd_interval * v)605 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
606 {
607 	int changed = 0;
608 	if (snd_BUG_ON(snd_interval_empty(i)))
609 		return -EINVAL;
610 	if (i->min < v->min) {
611 		i->min = v->min;
612 		i->openmin = v->openmin;
613 		changed = 1;
614 	} else if (i->min == v->min && !i->openmin && v->openmin) {
615 		i->openmin = 1;
616 		changed = 1;
617 	}
618 	if (i->max > v->max) {
619 		i->max = v->max;
620 		i->openmax = v->openmax;
621 		changed = 1;
622 	} else if (i->max == v->max && !i->openmax && v->openmax) {
623 		i->openmax = 1;
624 		changed = 1;
625 	}
626 	if (!i->integer && v->integer) {
627 		i->integer = 1;
628 		changed = 1;
629 	}
630 	if (i->integer) {
631 		if (i->openmin) {
632 			i->min++;
633 			i->openmin = 0;
634 		}
635 		if (i->openmax) {
636 			i->max--;
637 			i->openmax = 0;
638 		}
639 	} else if (!i->openmin && !i->openmax && i->min == i->max)
640 		i->integer = 1;
641 	if (snd_interval_checkempty(i)) {
642 		snd_interval_none(i);
643 		return -EINVAL;
644 	}
645 	return changed;
646 }
647 
648 EXPORT_SYMBOL(snd_interval_refine);
649 
snd_interval_refine_first(struct snd_interval * i)650 static int snd_interval_refine_first(struct snd_interval *i)
651 {
652 	const unsigned int last_max = i->max;
653 
654 	if (snd_BUG_ON(snd_interval_empty(i)))
655 		return -EINVAL;
656 	if (snd_interval_single(i))
657 		return 0;
658 	i->max = i->min;
659 	if (i->openmin)
660 		i->max++;
661 	/* only exclude max value if also excluded before refine */
662 	i->openmax = (i->openmax && i->max >= last_max);
663 	return 1;
664 }
665 
snd_interval_refine_last(struct snd_interval * i)666 static int snd_interval_refine_last(struct snd_interval *i)
667 {
668 	const unsigned int last_min = i->min;
669 
670 	if (snd_BUG_ON(snd_interval_empty(i)))
671 		return -EINVAL;
672 	if (snd_interval_single(i))
673 		return 0;
674 	i->min = i->max;
675 	if (i->openmax)
676 		i->min--;
677 	/* only exclude min value if also excluded before refine */
678 	i->openmin = (i->openmin && i->min <= last_min);
679 	return 1;
680 }
681 
snd_interval_mul(const struct snd_interval * a,const struct snd_interval * b,struct snd_interval * c)682 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
683 {
684 	if (a->empty || b->empty) {
685 		snd_interval_none(c);
686 		return;
687 	}
688 	c->empty = 0;
689 	c->min = mul(a->min, b->min);
690 	c->openmin = (a->openmin || b->openmin);
691 	c->max = mul(a->max,  b->max);
692 	c->openmax = (a->openmax || b->openmax);
693 	c->integer = (a->integer && b->integer);
694 }
695 
696 /**
697  * snd_interval_div - refine the interval value with division
698  * @a: dividend
699  * @b: divisor
700  * @c: quotient
701  *
702  * c = a / b
703  *
704  * Returns non-zero if the value is changed, zero if not changed.
705  */
snd_interval_div(const struct snd_interval * a,const struct snd_interval * b,struct snd_interval * c)706 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
707 {
708 	unsigned int r;
709 	if (a->empty || b->empty) {
710 		snd_interval_none(c);
711 		return;
712 	}
713 	c->empty = 0;
714 	c->min = div32(a->min, b->max, &r);
715 	c->openmin = (r || a->openmin || b->openmax);
716 	if (b->min > 0) {
717 		c->max = div32(a->max, b->min, &r);
718 		if (r) {
719 			c->max++;
720 			c->openmax = 1;
721 		} else
722 			c->openmax = (a->openmax || b->openmin);
723 	} else {
724 		c->max = UINT_MAX;
725 		c->openmax = 0;
726 	}
727 	c->integer = 0;
728 }
729 
730 /**
731  * snd_interval_muldivk - refine the interval value
732  * @a: dividend 1
733  * @b: dividend 2
734  * @k: divisor (as integer)
735  * @c: result
736   *
737  * c = a * b / k
738  *
739  * Returns non-zero if the value is changed, zero if not changed.
740  */
snd_interval_muldivk(const struct snd_interval * a,const struct snd_interval * b,unsigned int k,struct snd_interval * c)741 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
742 		      unsigned int k, struct snd_interval *c)
743 {
744 	unsigned int r;
745 	if (a->empty || b->empty) {
746 		snd_interval_none(c);
747 		return;
748 	}
749 	c->empty = 0;
750 	c->min = muldiv32(a->min, b->min, k, &r);
751 	c->openmin = (r || a->openmin || b->openmin);
752 	c->max = muldiv32(a->max, b->max, k, &r);
753 	if (r) {
754 		c->max++;
755 		c->openmax = 1;
756 	} else
757 		c->openmax = (a->openmax || b->openmax);
758 	c->integer = 0;
759 }
760 
761 /**
762  * snd_interval_mulkdiv - refine the interval value
763  * @a: dividend 1
764  * @k: dividend 2 (as integer)
765  * @b: divisor
766  * @c: result
767  *
768  * c = a * k / b
769  *
770  * Returns non-zero if the value is changed, zero if not changed.
771  */
snd_interval_mulkdiv(const struct snd_interval * a,unsigned int k,const struct snd_interval * b,struct snd_interval * c)772 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
773 		      const struct snd_interval *b, struct snd_interval *c)
774 {
775 	unsigned int r;
776 	if (a->empty || b->empty) {
777 		snd_interval_none(c);
778 		return;
779 	}
780 	c->empty = 0;
781 	c->min = muldiv32(a->min, k, b->max, &r);
782 	c->openmin = (r || a->openmin || b->openmax);
783 	if (b->min > 0) {
784 		c->max = muldiv32(a->max, k, b->min, &r);
785 		if (r) {
786 			c->max++;
787 			c->openmax = 1;
788 		} else
789 			c->openmax = (a->openmax || b->openmin);
790 	} else {
791 		c->max = UINT_MAX;
792 		c->openmax = 0;
793 	}
794 	c->integer = 0;
795 }
796 
797 /* ---- */
798 
799 
800 /**
801  * snd_interval_ratnum - refine the interval value
802  * @i: interval to refine
803  * @rats_count: number of ratnum_t
804  * @rats: ratnum_t array
805  * @nump: pointer to store the resultant numerator
806  * @denp: pointer to store the resultant denominator
807  *
808  * Return: Positive if the value is changed, zero if it's not changed, or a
809  * negative error code.
810  */
snd_interval_ratnum(struct snd_interval * i,unsigned int rats_count,const struct snd_ratnum * rats,unsigned int * nump,unsigned int * denp)811 int snd_interval_ratnum(struct snd_interval *i,
812 			unsigned int rats_count, const struct snd_ratnum *rats,
813 			unsigned int *nump, unsigned int *denp)
814 {
815 	unsigned int best_num, best_den;
816 	int best_diff;
817 	unsigned int k;
818 	struct snd_interval t;
819 	int err;
820 	unsigned int result_num, result_den;
821 	int result_diff;
822 
823 	best_num = best_den = best_diff = 0;
824 	for (k = 0; k < rats_count; ++k) {
825 		unsigned int num = rats[k].num;
826 		unsigned int den;
827 		unsigned int q = i->min;
828 		int diff;
829 		if (q == 0)
830 			q = 1;
831 		den = div_up(num, q);
832 		if (den < rats[k].den_min)
833 			continue;
834 		if (den > rats[k].den_max)
835 			den = rats[k].den_max;
836 		else {
837 			unsigned int r;
838 			r = (den - rats[k].den_min) % rats[k].den_step;
839 			if (r != 0)
840 				den -= r;
841 		}
842 		diff = num - q * den;
843 		if (diff < 0)
844 			diff = -diff;
845 		if (best_num == 0 ||
846 		    diff * best_den < best_diff * den) {
847 			best_diff = diff;
848 			best_den = den;
849 			best_num = num;
850 		}
851 	}
852 	if (best_den == 0) {
853 		i->empty = 1;
854 		return -EINVAL;
855 	}
856 	t.min = div_down(best_num, best_den);
857 	t.openmin = !!(best_num % best_den);
858 
859 	result_num = best_num;
860 	result_diff = best_diff;
861 	result_den = best_den;
862 	best_num = best_den = best_diff = 0;
863 	for (k = 0; k < rats_count; ++k) {
864 		unsigned int num = rats[k].num;
865 		unsigned int den;
866 		unsigned int q = i->max;
867 		int diff;
868 		if (q == 0) {
869 			i->empty = 1;
870 			return -EINVAL;
871 		}
872 		den = div_down(num, q);
873 		if (den > rats[k].den_max)
874 			continue;
875 		if (den < rats[k].den_min)
876 			den = rats[k].den_min;
877 		else {
878 			unsigned int r;
879 			r = (den - rats[k].den_min) % rats[k].den_step;
880 			if (r != 0)
881 				den += rats[k].den_step - r;
882 		}
883 		diff = q * den - num;
884 		if (diff < 0)
885 			diff = -diff;
886 		if (best_num == 0 ||
887 		    diff * best_den < best_diff * den) {
888 			best_diff = diff;
889 			best_den = den;
890 			best_num = num;
891 		}
892 	}
893 	if (best_den == 0) {
894 		i->empty = 1;
895 		return -EINVAL;
896 	}
897 	t.max = div_up(best_num, best_den);
898 	t.openmax = !!(best_num % best_den);
899 	t.integer = 0;
900 	err = snd_interval_refine(i, &t);
901 	if (err < 0)
902 		return err;
903 
904 	if (snd_interval_single(i)) {
905 		if (best_diff * result_den < result_diff * best_den) {
906 			result_num = best_num;
907 			result_den = best_den;
908 		}
909 		if (nump)
910 			*nump = result_num;
911 		if (denp)
912 			*denp = result_den;
913 	}
914 	return err;
915 }
916 
917 EXPORT_SYMBOL(snd_interval_ratnum);
918 
919 /**
920  * snd_interval_ratden - refine the interval value
921  * @i: interval to refine
922  * @rats_count: number of struct ratden
923  * @rats: struct ratden array
924  * @nump: pointer to store the resultant numerator
925  * @denp: pointer to store the resultant denominator
926  *
927  * Return: Positive if the value is changed, zero if it's not changed, or a
928  * negative error code.
929  */
snd_interval_ratden(struct snd_interval * i,unsigned int rats_count,const struct snd_ratden * rats,unsigned int * nump,unsigned int * denp)930 static int snd_interval_ratden(struct snd_interval *i,
931 			       unsigned int rats_count,
932 			       const struct snd_ratden *rats,
933 			       unsigned int *nump, unsigned int *denp)
934 {
935 	unsigned int best_num, best_diff, best_den;
936 	unsigned int k;
937 	struct snd_interval t;
938 	int err;
939 
940 	best_num = best_den = best_diff = 0;
941 	for (k = 0; k < rats_count; ++k) {
942 		unsigned int num;
943 		unsigned int den = rats[k].den;
944 		unsigned int q = i->min;
945 		int diff;
946 		num = mul(q, den);
947 		if (num > rats[k].num_max)
948 			continue;
949 		if (num < rats[k].num_min)
950 			num = rats[k].num_max;
951 		else {
952 			unsigned int r;
953 			r = (num - rats[k].num_min) % rats[k].num_step;
954 			if (r != 0)
955 				num += rats[k].num_step - r;
956 		}
957 		diff = num - q * den;
958 		if (best_num == 0 ||
959 		    diff * best_den < best_diff * den) {
960 			best_diff = diff;
961 			best_den = den;
962 			best_num = num;
963 		}
964 	}
965 	if (best_den == 0) {
966 		i->empty = 1;
967 		return -EINVAL;
968 	}
969 	t.min = div_down(best_num, best_den);
970 	t.openmin = !!(best_num % best_den);
971 
972 	best_num = best_den = best_diff = 0;
973 	for (k = 0; k < rats_count; ++k) {
974 		unsigned int num;
975 		unsigned int den = rats[k].den;
976 		unsigned int q = i->max;
977 		int diff;
978 		num = mul(q, den);
979 		if (num < rats[k].num_min)
980 			continue;
981 		if (num > rats[k].num_max)
982 			num = rats[k].num_max;
983 		else {
984 			unsigned int r;
985 			r = (num - rats[k].num_min) % rats[k].num_step;
986 			if (r != 0)
987 				num -= r;
988 		}
989 		diff = q * den - num;
990 		if (best_num == 0 ||
991 		    diff * best_den < best_diff * den) {
992 			best_diff = diff;
993 			best_den = den;
994 			best_num = num;
995 		}
996 	}
997 	if (best_den == 0) {
998 		i->empty = 1;
999 		return -EINVAL;
1000 	}
1001 	t.max = div_up(best_num, best_den);
1002 	t.openmax = !!(best_num % best_den);
1003 	t.integer = 0;
1004 	err = snd_interval_refine(i, &t);
1005 	if (err < 0)
1006 		return err;
1007 
1008 	if (snd_interval_single(i)) {
1009 		if (nump)
1010 			*nump = best_num;
1011 		if (denp)
1012 			*denp = best_den;
1013 	}
1014 	return err;
1015 }
1016 
1017 /**
1018  * snd_interval_list - refine the interval value from the list
1019  * @i: the interval value to refine
1020  * @count: the number of elements in the list
1021  * @list: the value list
1022  * @mask: the bit-mask to evaluate
1023  *
1024  * Refines the interval value from the list.
1025  * When mask is non-zero, only the elements corresponding to bit 1 are
1026  * evaluated.
1027  *
1028  * Return: Positive if the value is changed, zero if it's not changed, or a
1029  * negative error code.
1030  */
snd_interval_list(struct snd_interval * i,unsigned int count,const unsigned int * list,unsigned int mask)1031 int snd_interval_list(struct snd_interval *i, unsigned int count,
1032 		      const unsigned int *list, unsigned int mask)
1033 {
1034         unsigned int k;
1035 	struct snd_interval list_range;
1036 
1037 	if (!count) {
1038 		i->empty = 1;
1039 		return -EINVAL;
1040 	}
1041 	snd_interval_any(&list_range);
1042 	list_range.min = UINT_MAX;
1043 	list_range.max = 0;
1044         for (k = 0; k < count; k++) {
1045 		if (mask && !(mask & (1 << k)))
1046 			continue;
1047 		if (!snd_interval_test(i, list[k]))
1048 			continue;
1049 		list_range.min = min(list_range.min, list[k]);
1050 		list_range.max = max(list_range.max, list[k]);
1051         }
1052 	return snd_interval_refine(i, &list_range);
1053 }
1054 
1055 EXPORT_SYMBOL(snd_interval_list);
1056 
1057 /**
1058  * snd_interval_ranges - refine the interval value from the list of ranges
1059  * @i: the interval value to refine
1060  * @count: the number of elements in the list of ranges
1061  * @ranges: the ranges list
1062  * @mask: the bit-mask to evaluate
1063  *
1064  * Refines the interval value from the list of ranges.
1065  * When mask is non-zero, only the elements corresponding to bit 1 are
1066  * evaluated.
1067  *
1068  * Return: Positive if the value is changed, zero if it's not changed, or a
1069  * negative error code.
1070  */
snd_interval_ranges(struct snd_interval * i,unsigned int count,const struct snd_interval * ranges,unsigned int mask)1071 int snd_interval_ranges(struct snd_interval *i, unsigned int count,
1072 			const struct snd_interval *ranges, unsigned int mask)
1073 {
1074 	unsigned int k;
1075 	struct snd_interval range_union;
1076 	struct snd_interval range;
1077 
1078 	if (!count) {
1079 		snd_interval_none(i);
1080 		return -EINVAL;
1081 	}
1082 	snd_interval_any(&range_union);
1083 	range_union.min = UINT_MAX;
1084 	range_union.max = 0;
1085 	for (k = 0; k < count; k++) {
1086 		if (mask && !(mask & (1 << k)))
1087 			continue;
1088 		snd_interval_copy(&range, &ranges[k]);
1089 		if (snd_interval_refine(&range, i) < 0)
1090 			continue;
1091 		if (snd_interval_empty(&range))
1092 			continue;
1093 
1094 		if (range.min < range_union.min) {
1095 			range_union.min = range.min;
1096 			range_union.openmin = 1;
1097 		}
1098 		if (range.min == range_union.min && !range.openmin)
1099 			range_union.openmin = 0;
1100 		if (range.max > range_union.max) {
1101 			range_union.max = range.max;
1102 			range_union.openmax = 1;
1103 		}
1104 		if (range.max == range_union.max && !range.openmax)
1105 			range_union.openmax = 0;
1106 	}
1107 	return snd_interval_refine(i, &range_union);
1108 }
1109 EXPORT_SYMBOL(snd_interval_ranges);
1110 
snd_interval_step(struct snd_interval * i,unsigned int step)1111 static int snd_interval_step(struct snd_interval *i, unsigned int step)
1112 {
1113 	unsigned int n;
1114 	int changed = 0;
1115 	n = i->min % step;
1116 	if (n != 0 || i->openmin) {
1117 		i->min += step - n;
1118 		i->openmin = 0;
1119 		changed = 1;
1120 	}
1121 	n = i->max % step;
1122 	if (n != 0 || i->openmax) {
1123 		i->max -= n;
1124 		i->openmax = 0;
1125 		changed = 1;
1126 	}
1127 	if (snd_interval_checkempty(i)) {
1128 		i->empty = 1;
1129 		return -EINVAL;
1130 	}
1131 	return changed;
1132 }
1133 
1134 /* Info constraints helpers */
1135 
1136 /**
1137  * snd_pcm_hw_rule_add - add the hw-constraint rule
1138  * @runtime: the pcm runtime instance
1139  * @cond: condition bits
1140  * @var: the variable to evaluate
1141  * @func: the evaluation function
1142  * @private: the private data pointer passed to function
1143  * @dep: the dependent variables
1144  *
1145  * Return: Zero if successful, or a negative error code on failure.
1146  */
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,...)1147 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1148 			int var,
1149 			snd_pcm_hw_rule_func_t func, void *private,
1150 			int dep, ...)
1151 {
1152 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1153 	struct snd_pcm_hw_rule *c;
1154 	unsigned int k;
1155 	va_list args;
1156 	va_start(args, dep);
1157 	if (constrs->rules_num >= constrs->rules_all) {
1158 		struct snd_pcm_hw_rule *new;
1159 		unsigned int new_rules = constrs->rules_all + 16;
1160 		new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1161 		if (!new) {
1162 			va_end(args);
1163 			return -ENOMEM;
1164 		}
1165 		if (constrs->rules) {
1166 			memcpy(new, constrs->rules,
1167 			       constrs->rules_num * sizeof(*c));
1168 			kfree(constrs->rules);
1169 		}
1170 		constrs->rules = new;
1171 		constrs->rules_all = new_rules;
1172 	}
1173 	c = &constrs->rules[constrs->rules_num];
1174 	c->cond = cond;
1175 	c->func = func;
1176 	c->var = var;
1177 	c->private = private;
1178 	k = 0;
1179 	while (1) {
1180 		if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1181 			va_end(args);
1182 			return -EINVAL;
1183 		}
1184 		c->deps[k++] = dep;
1185 		if (dep < 0)
1186 			break;
1187 		dep = va_arg(args, int);
1188 	}
1189 	constrs->rules_num++;
1190 	va_end(args);
1191 	return 0;
1192 }
1193 
1194 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1195 
1196 /**
1197  * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1198  * @runtime: PCM runtime instance
1199  * @var: hw_params variable to apply the mask
1200  * @mask: the bitmap mask
1201  *
1202  * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1203  *
1204  * Return: Zero if successful, or a negative error code on failure.
1205  */
snd_pcm_hw_constraint_mask(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var,u_int32_t mask)1206 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1207 			       u_int32_t mask)
1208 {
1209 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1210 	struct snd_mask *maskp = constrs_mask(constrs, var);
1211 	*maskp->bits &= mask;
1212 	memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1213 	if (*maskp->bits == 0)
1214 		return -EINVAL;
1215 	return 0;
1216 }
1217 
1218 /**
1219  * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1220  * @runtime: PCM runtime instance
1221  * @var: hw_params variable to apply the mask
1222  * @mask: the 64bit bitmap mask
1223  *
1224  * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1225  *
1226  * Return: Zero if successful, or a negative error code on failure.
1227  */
snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var,u_int64_t mask)1228 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1229 				 u_int64_t mask)
1230 {
1231 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1232 	struct snd_mask *maskp = constrs_mask(constrs, var);
1233 	maskp->bits[0] &= (u_int32_t)mask;
1234 	maskp->bits[1] &= (u_int32_t)(mask >> 32);
1235 	memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1236 	if (! maskp->bits[0] && ! maskp->bits[1])
1237 		return -EINVAL;
1238 	return 0;
1239 }
1240 EXPORT_SYMBOL(snd_pcm_hw_constraint_mask64);
1241 
1242 /**
1243  * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1244  * @runtime: PCM runtime instance
1245  * @var: hw_params variable to apply the integer constraint
1246  *
1247  * Apply the constraint of integer to an interval parameter.
1248  *
1249  * Return: Positive if the value is changed, zero if it's not changed, or a
1250  * negative error code.
1251  */
snd_pcm_hw_constraint_integer(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var)1252 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1253 {
1254 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1255 	return snd_interval_setinteger(constrs_interval(constrs, var));
1256 }
1257 
1258 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1259 
1260 /**
1261  * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1262  * @runtime: PCM runtime instance
1263  * @var: hw_params variable to apply the range
1264  * @min: the minimal value
1265  * @max: the maximal value
1266  *
1267  * Apply the min/max range constraint to an interval parameter.
1268  *
1269  * Return: Positive if the value is changed, zero if it's not changed, or a
1270  * negative error code.
1271  */
snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var,unsigned int min,unsigned int max)1272 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1273 				 unsigned int min, unsigned int max)
1274 {
1275 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1276 	struct snd_interval t;
1277 	t.min = min;
1278 	t.max = max;
1279 	t.openmin = t.openmax = 0;
1280 	t.integer = 0;
1281 	return snd_interval_refine(constrs_interval(constrs, var), &t);
1282 }
1283 
1284 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1285 
snd_pcm_hw_rule_list(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1286 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1287 				struct snd_pcm_hw_rule *rule)
1288 {
1289 	struct snd_pcm_hw_constraint_list *list = rule->private;
1290 	return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1291 }
1292 
1293 
1294 /**
1295  * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1296  * @runtime: PCM runtime instance
1297  * @cond: condition bits
1298  * @var: hw_params variable to apply the list constraint
1299  * @l: list
1300  *
1301  * Apply the list of constraints to an interval parameter.
1302  *
1303  * Return: Zero if successful, or a negative error code on failure.
1304  */
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)1305 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1306 			       unsigned int cond,
1307 			       snd_pcm_hw_param_t var,
1308 			       const struct snd_pcm_hw_constraint_list *l)
1309 {
1310 	return snd_pcm_hw_rule_add(runtime, cond, var,
1311 				   snd_pcm_hw_rule_list, (void *)l,
1312 				   var, -1);
1313 }
1314 
1315 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1316 
snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1317 static int snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params *params,
1318 				  struct snd_pcm_hw_rule *rule)
1319 {
1320 	struct snd_pcm_hw_constraint_ranges *r = rule->private;
1321 	return snd_interval_ranges(hw_param_interval(params, rule->var),
1322 				   r->count, r->ranges, r->mask);
1323 }
1324 
1325 
1326 /**
1327  * snd_pcm_hw_constraint_ranges - apply list of range constraints to a parameter
1328  * @runtime: PCM runtime instance
1329  * @cond: condition bits
1330  * @var: hw_params variable to apply the list of range constraints
1331  * @r: ranges
1332  *
1333  * Apply the list of range constraints to an interval parameter.
1334  *
1335  * Return: Zero if successful, or a negative error code on failure.
1336  */
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)1337 int snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime *runtime,
1338 				 unsigned int cond,
1339 				 snd_pcm_hw_param_t var,
1340 				 const struct snd_pcm_hw_constraint_ranges *r)
1341 {
1342 	return snd_pcm_hw_rule_add(runtime, cond, var,
1343 				   snd_pcm_hw_rule_ranges, (void *)r,
1344 				   var, -1);
1345 }
1346 EXPORT_SYMBOL(snd_pcm_hw_constraint_ranges);
1347 
snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1348 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1349 				   struct snd_pcm_hw_rule *rule)
1350 {
1351 	const struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1352 	unsigned int num = 0, den = 0;
1353 	int err;
1354 	err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1355 				  r->nrats, r->rats, &num, &den);
1356 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1357 		params->rate_num = num;
1358 		params->rate_den = den;
1359 	}
1360 	return err;
1361 }
1362 
1363 /**
1364  * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1365  * @runtime: PCM runtime instance
1366  * @cond: condition bits
1367  * @var: hw_params variable to apply the ratnums constraint
1368  * @r: struct snd_ratnums constriants
1369  *
1370  * Return: Zero if successful, or a negative error code on failure.
1371  */
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)1372 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1373 				  unsigned int cond,
1374 				  snd_pcm_hw_param_t var,
1375 				  const struct snd_pcm_hw_constraint_ratnums *r)
1376 {
1377 	return snd_pcm_hw_rule_add(runtime, cond, var,
1378 				   snd_pcm_hw_rule_ratnums, (void *)r,
1379 				   var, -1);
1380 }
1381 
1382 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1383 
snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1384 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1385 				   struct snd_pcm_hw_rule *rule)
1386 {
1387 	const struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1388 	unsigned int num = 0, den = 0;
1389 	int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1390 				  r->nrats, r->rats, &num, &den);
1391 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1392 		params->rate_num = num;
1393 		params->rate_den = den;
1394 	}
1395 	return err;
1396 }
1397 
1398 /**
1399  * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1400  * @runtime: PCM runtime instance
1401  * @cond: condition bits
1402  * @var: hw_params variable to apply the ratdens constraint
1403  * @r: struct snd_ratdens constriants
1404  *
1405  * Return: Zero if successful, or a negative error code on failure.
1406  */
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)1407 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1408 				  unsigned int cond,
1409 				  snd_pcm_hw_param_t var,
1410 				  const struct snd_pcm_hw_constraint_ratdens *r)
1411 {
1412 	return snd_pcm_hw_rule_add(runtime, cond, var,
1413 				   snd_pcm_hw_rule_ratdens, (void *)r,
1414 				   var, -1);
1415 }
1416 
1417 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1418 
snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1419 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1420 				  struct snd_pcm_hw_rule *rule)
1421 {
1422 	unsigned int l = (unsigned long) rule->private;
1423 	int width = l & 0xffff;
1424 	unsigned int msbits = l >> 16;
1425 	struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1426 
1427 	if (!snd_interval_single(i))
1428 		return 0;
1429 
1430 	if ((snd_interval_value(i) == width) ||
1431 	    (width == 0 && snd_interval_value(i) > msbits))
1432 		params->msbits = min_not_zero(params->msbits, msbits);
1433 
1434 	return 0;
1435 }
1436 
1437 /**
1438  * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1439  * @runtime: PCM runtime instance
1440  * @cond: condition bits
1441  * @width: sample bits width
1442  * @msbits: msbits width
1443  *
1444  * This constraint will set the number of most significant bits (msbits) if a
1445  * sample format with the specified width has been select. If width is set to 0
1446  * the msbits will be set for any sample format with a width larger than the
1447  * specified msbits.
1448  *
1449  * Return: Zero if successful, or a negative error code on failure.
1450  */
snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime * runtime,unsigned int cond,unsigned int width,unsigned int msbits)1451 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1452 				 unsigned int cond,
1453 				 unsigned int width,
1454 				 unsigned int msbits)
1455 {
1456 	unsigned long l = (msbits << 16) | width;
1457 	return snd_pcm_hw_rule_add(runtime, cond, -1,
1458 				    snd_pcm_hw_rule_msbits,
1459 				    (void*) l,
1460 				    SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1461 }
1462 
1463 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1464 
snd_pcm_hw_rule_step(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1465 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1466 				struct snd_pcm_hw_rule *rule)
1467 {
1468 	unsigned long step = (unsigned long) rule->private;
1469 	return snd_interval_step(hw_param_interval(params, rule->var), step);
1470 }
1471 
1472 /**
1473  * snd_pcm_hw_constraint_step - add a hw constraint step rule
1474  * @runtime: PCM runtime instance
1475  * @cond: condition bits
1476  * @var: hw_params variable to apply the step constraint
1477  * @step: step size
1478  *
1479  * Return: Zero if successful, or a negative error code on failure.
1480  */
snd_pcm_hw_constraint_step(struct snd_pcm_runtime * runtime,unsigned int cond,snd_pcm_hw_param_t var,unsigned long step)1481 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1482 			       unsigned int cond,
1483 			       snd_pcm_hw_param_t var,
1484 			       unsigned long step)
1485 {
1486 	return snd_pcm_hw_rule_add(runtime, cond, var,
1487 				   snd_pcm_hw_rule_step, (void *) step,
1488 				   var, -1);
1489 }
1490 
1491 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1492 
snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1493 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1494 {
1495 	static unsigned int pow2_sizes[] = {
1496 		1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1497 		1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1498 		1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1499 		1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1500 	};
1501 	return snd_interval_list(hw_param_interval(params, rule->var),
1502 				 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1503 }
1504 
1505 /**
1506  * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1507  * @runtime: PCM runtime instance
1508  * @cond: condition bits
1509  * @var: hw_params variable to apply the power-of-2 constraint
1510  *
1511  * Return: Zero if successful, or a negative error code on failure.
1512  */
snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime * runtime,unsigned int cond,snd_pcm_hw_param_t var)1513 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1514 			       unsigned int cond,
1515 			       snd_pcm_hw_param_t var)
1516 {
1517 	return snd_pcm_hw_rule_add(runtime, cond, var,
1518 				   snd_pcm_hw_rule_pow2, NULL,
1519 				   var, -1);
1520 }
1521 
1522 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1523 
snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1524 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1525 					   struct snd_pcm_hw_rule *rule)
1526 {
1527 	unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1528 	struct snd_interval *rate;
1529 
1530 	rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1531 	return snd_interval_list(rate, 1, &base_rate, 0);
1532 }
1533 
1534 /**
1535  * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1536  * @runtime: PCM runtime instance
1537  * @base_rate: the rate at which the hardware does not resample
1538  *
1539  * Return: Zero if successful, or a negative error code on failure.
1540  */
snd_pcm_hw_rule_noresample(struct snd_pcm_runtime * runtime,unsigned int base_rate)1541 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1542 			       unsigned int base_rate)
1543 {
1544 	return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1545 				   SNDRV_PCM_HW_PARAM_RATE,
1546 				   snd_pcm_hw_rule_noresample_func,
1547 				   (void *)(uintptr_t)base_rate,
1548 				   SNDRV_PCM_HW_PARAM_RATE, -1);
1549 }
1550 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1551 
_snd_pcm_hw_param_any(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1552 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1553 				  snd_pcm_hw_param_t var)
1554 {
1555 	if (hw_is_mask(var)) {
1556 		snd_mask_any(hw_param_mask(params, var));
1557 		params->cmask |= 1 << var;
1558 		params->rmask |= 1 << var;
1559 		return;
1560 	}
1561 	if (hw_is_interval(var)) {
1562 		snd_interval_any(hw_param_interval(params, var));
1563 		params->cmask |= 1 << var;
1564 		params->rmask |= 1 << var;
1565 		return;
1566 	}
1567 	snd_BUG();
1568 }
1569 
_snd_pcm_hw_params_any(struct snd_pcm_hw_params * params)1570 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1571 {
1572 	unsigned int k;
1573 	memset(params, 0, sizeof(*params));
1574 	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1575 		_snd_pcm_hw_param_any(params, k);
1576 	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1577 		_snd_pcm_hw_param_any(params, k);
1578 	params->info = ~0U;
1579 }
1580 
1581 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1582 
1583 /**
1584  * snd_pcm_hw_param_value - return @params field @var value
1585  * @params: the hw_params instance
1586  * @var: parameter to retrieve
1587  * @dir: pointer to the direction (-1,0,1) or %NULL
1588  *
1589  * Return: The value for field @var if it's fixed in configuration space
1590  * defined by @params. -%EINVAL otherwise.
1591  */
snd_pcm_hw_param_value(const struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var,int * dir)1592 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1593 			   snd_pcm_hw_param_t var, int *dir)
1594 {
1595 	if (hw_is_mask(var)) {
1596 		const struct snd_mask *mask = hw_param_mask_c(params, var);
1597 		if (!snd_mask_single(mask))
1598 			return -EINVAL;
1599 		if (dir)
1600 			*dir = 0;
1601 		return snd_mask_value(mask);
1602 	}
1603 	if (hw_is_interval(var)) {
1604 		const struct snd_interval *i = hw_param_interval_c(params, var);
1605 		if (!snd_interval_single(i))
1606 			return -EINVAL;
1607 		if (dir)
1608 			*dir = i->openmin;
1609 		return snd_interval_value(i);
1610 	}
1611 	return -EINVAL;
1612 }
1613 
1614 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1615 
_snd_pcm_hw_param_setempty(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1616 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1617 				snd_pcm_hw_param_t var)
1618 {
1619 	if (hw_is_mask(var)) {
1620 		snd_mask_none(hw_param_mask(params, var));
1621 		params->cmask |= 1 << var;
1622 		params->rmask |= 1 << var;
1623 	} else if (hw_is_interval(var)) {
1624 		snd_interval_none(hw_param_interval(params, var));
1625 		params->cmask |= 1 << var;
1626 		params->rmask |= 1 << var;
1627 	} else {
1628 		snd_BUG();
1629 	}
1630 }
1631 
1632 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1633 
_snd_pcm_hw_param_first(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1634 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1635 				   snd_pcm_hw_param_t var)
1636 {
1637 	int changed;
1638 	if (hw_is_mask(var))
1639 		changed = snd_mask_refine_first(hw_param_mask(params, var));
1640 	else if (hw_is_interval(var))
1641 		changed = snd_interval_refine_first(hw_param_interval(params, var));
1642 	else
1643 		return -EINVAL;
1644 	if (changed) {
1645 		params->cmask |= 1 << var;
1646 		params->rmask |= 1 << var;
1647 	}
1648 	return changed;
1649 }
1650 
1651 
1652 /**
1653  * snd_pcm_hw_param_first - refine config space and return minimum value
1654  * @pcm: PCM instance
1655  * @params: the hw_params instance
1656  * @var: parameter to retrieve
1657  * @dir: pointer to the direction (-1,0,1) or %NULL
1658  *
1659  * Inside configuration space defined by @params remove from @var all
1660  * values > minimum. Reduce configuration space accordingly.
1661  *
1662  * Return: The minimum, or a negative error code on failure.
1663  */
snd_pcm_hw_param_first(struct snd_pcm_substream * pcm,struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var,int * dir)1664 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1665 			   struct snd_pcm_hw_params *params,
1666 			   snd_pcm_hw_param_t var, int *dir)
1667 {
1668 	int changed = _snd_pcm_hw_param_first(params, var);
1669 	if (changed < 0)
1670 		return changed;
1671 	if (params->rmask) {
1672 		int err = snd_pcm_hw_refine(pcm, params);
1673 		if (err < 0)
1674 			return err;
1675 	}
1676 	return snd_pcm_hw_param_value(params, var, dir);
1677 }
1678 
1679 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1680 
_snd_pcm_hw_param_last(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1681 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1682 				  snd_pcm_hw_param_t var)
1683 {
1684 	int changed;
1685 	if (hw_is_mask(var))
1686 		changed = snd_mask_refine_last(hw_param_mask(params, var));
1687 	else if (hw_is_interval(var))
1688 		changed = snd_interval_refine_last(hw_param_interval(params, var));
1689 	else
1690 		return -EINVAL;
1691 	if (changed) {
1692 		params->cmask |= 1 << var;
1693 		params->rmask |= 1 << var;
1694 	}
1695 	return changed;
1696 }
1697 
1698 
1699 /**
1700  * snd_pcm_hw_param_last - refine config space and return maximum value
1701  * @pcm: PCM instance
1702  * @params: the hw_params instance
1703  * @var: parameter to retrieve
1704  * @dir: pointer to the direction (-1,0,1) or %NULL
1705  *
1706  * Inside configuration space defined by @params remove from @var all
1707  * values < maximum. Reduce configuration space accordingly.
1708  *
1709  * Return: The maximum, or a negative error code on failure.
1710  */
snd_pcm_hw_param_last(struct snd_pcm_substream * pcm,struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var,int * dir)1711 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1712 			  struct snd_pcm_hw_params *params,
1713 			  snd_pcm_hw_param_t var, int *dir)
1714 {
1715 	int changed = _snd_pcm_hw_param_last(params, var);
1716 	if (changed < 0)
1717 		return changed;
1718 	if (params->rmask) {
1719 		int err = snd_pcm_hw_refine(pcm, params);
1720 		if (err < 0)
1721 			return err;
1722 	}
1723 	return snd_pcm_hw_param_value(params, var, dir);
1724 }
1725 
1726 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1727 
1728 /**
1729  * snd_pcm_hw_param_choose - choose a configuration defined by @params
1730  * @pcm: PCM instance
1731  * @params: the hw_params instance
1732  *
1733  * Choose one configuration from configuration space defined by @params.
1734  * The configuration chosen is that obtained fixing in this order:
1735  * first access, first format, first subformat, min channels,
1736  * min rate, min period time, max buffer size, min tick time
1737  *
1738  * Return: Zero if successful, or a negative error code on failure.
1739  */
snd_pcm_hw_params_choose(struct snd_pcm_substream * pcm,struct snd_pcm_hw_params * params)1740 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1741 			     struct snd_pcm_hw_params *params)
1742 {
1743 	static int vars[] = {
1744 		SNDRV_PCM_HW_PARAM_ACCESS,
1745 		SNDRV_PCM_HW_PARAM_FORMAT,
1746 		SNDRV_PCM_HW_PARAM_SUBFORMAT,
1747 		SNDRV_PCM_HW_PARAM_CHANNELS,
1748 		SNDRV_PCM_HW_PARAM_RATE,
1749 		SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1750 		SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1751 		SNDRV_PCM_HW_PARAM_TICK_TIME,
1752 		-1
1753 	};
1754 	int err, *v;
1755 
1756 	for (v = vars; *v != -1; v++) {
1757 		if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1758 			err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1759 		else
1760 			err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1761 		if (snd_BUG_ON(err < 0))
1762 			return err;
1763 	}
1764 	return 0;
1765 }
1766 
snd_pcm_lib_ioctl_reset(struct snd_pcm_substream * substream,void * arg)1767 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1768 				   void *arg)
1769 {
1770 	struct snd_pcm_runtime *runtime = substream->runtime;
1771 	unsigned long flags;
1772 	snd_pcm_stream_lock_irqsave(substream, flags);
1773 	if (snd_pcm_running(substream) &&
1774 	    snd_pcm_update_hw_ptr(substream) >= 0)
1775 		runtime->status->hw_ptr %= runtime->buffer_size;
1776 	else {
1777 		runtime->status->hw_ptr = 0;
1778 		runtime->hw_ptr_wrap = 0;
1779 	}
1780 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1781 	return 0;
1782 }
1783 
snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream * substream,void * arg)1784 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1785 					  void *arg)
1786 {
1787 	struct snd_pcm_channel_info *info = arg;
1788 	struct snd_pcm_runtime *runtime = substream->runtime;
1789 	int width;
1790 	if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1791 		info->offset = -1;
1792 		return 0;
1793 	}
1794 	width = snd_pcm_format_physical_width(runtime->format);
1795 	if (width < 0)
1796 		return width;
1797 	info->offset = 0;
1798 	switch (runtime->access) {
1799 	case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1800 	case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1801 		info->first = info->channel * width;
1802 		info->step = runtime->channels * width;
1803 		break;
1804 	case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1805 	case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1806 	{
1807 		size_t size = runtime->dma_bytes / runtime->channels;
1808 		info->first = info->channel * size * 8;
1809 		info->step = width;
1810 		break;
1811 	}
1812 	default:
1813 		snd_BUG();
1814 		break;
1815 	}
1816 	return 0;
1817 }
1818 
snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream * substream,void * arg)1819 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1820 				       void *arg)
1821 {
1822 	struct snd_pcm_hw_params *params = arg;
1823 	snd_pcm_format_t format;
1824 	int channels;
1825 	ssize_t frame_size;
1826 
1827 	params->fifo_size = substream->runtime->hw.fifo_size;
1828 	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1829 		format = params_format(params);
1830 		channels = params_channels(params);
1831 		frame_size = snd_pcm_format_size(format, channels);
1832 		if (frame_size > 0)
1833 			params->fifo_size /= frame_size;
1834 	}
1835 	return 0;
1836 }
1837 
1838 /**
1839  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1840  * @substream: the pcm substream instance
1841  * @cmd: ioctl command
1842  * @arg: ioctl argument
1843  *
1844  * Processes the generic ioctl commands for PCM.
1845  * Can be passed as the ioctl callback for PCM ops.
1846  *
1847  * Return: Zero if successful, or a negative error code on failure.
1848  */
snd_pcm_lib_ioctl(struct snd_pcm_substream * substream,unsigned int cmd,void * arg)1849 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1850 		      unsigned int cmd, void *arg)
1851 {
1852 	switch (cmd) {
1853 	case SNDRV_PCM_IOCTL1_RESET:
1854 		return snd_pcm_lib_ioctl_reset(substream, arg);
1855 	case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1856 		return snd_pcm_lib_ioctl_channel_info(substream, arg);
1857 	case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1858 		return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1859 	}
1860 	return -ENXIO;
1861 }
1862 
1863 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1864 
1865 /**
1866  * snd_pcm_period_elapsed - update the pcm status for the next period
1867  * @substream: the pcm substream instance
1868  *
1869  * This function is called from the interrupt handler when the
1870  * PCM has processed the period size.  It will update the current
1871  * pointer, wake up sleepers, etc.
1872  *
1873  * Even if more than one periods have elapsed since the last call, you
1874  * have to call this only once.
1875  */
snd_pcm_period_elapsed(struct snd_pcm_substream * substream)1876 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1877 {
1878 	struct snd_pcm_runtime *runtime;
1879 	unsigned long flags;
1880 
1881 	if (snd_BUG_ON(!substream))
1882 		return;
1883 
1884 	snd_pcm_stream_lock_irqsave(substream, flags);
1885 	if (PCM_RUNTIME_CHECK(substream))
1886 		goto _unlock;
1887 	runtime = substream->runtime;
1888 
1889 	if (!snd_pcm_running(substream) ||
1890 	    snd_pcm_update_hw_ptr0(substream, 1) < 0)
1891 		goto _end;
1892 
1893 #ifdef CONFIG_SND_PCM_TIMER
1894 	if (substream->timer_running)
1895 		snd_timer_interrupt(substream->timer, 1);
1896 #endif
1897  _end:
1898 	kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1899  _unlock:
1900 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1901 }
1902 
1903 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1904 
1905 /*
1906  * Wait until avail_min data becomes available
1907  * Returns a negative error code if any error occurs during operation.
1908  * The available space is stored on availp.  When err = 0 and avail = 0
1909  * on the capture stream, it indicates the stream is in DRAINING state.
1910  */
wait_for_avail(struct snd_pcm_substream * substream,snd_pcm_uframes_t * availp)1911 static int wait_for_avail(struct snd_pcm_substream *substream,
1912 			      snd_pcm_uframes_t *availp)
1913 {
1914 	struct snd_pcm_runtime *runtime = substream->runtime;
1915 	int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1916 	wait_queue_t wait;
1917 	int err = 0;
1918 	snd_pcm_uframes_t avail = 0;
1919 	long wait_time, tout;
1920 
1921 	init_waitqueue_entry(&wait, current);
1922 	set_current_state(TASK_INTERRUPTIBLE);
1923 	add_wait_queue(&runtime->tsleep, &wait);
1924 
1925 	if (runtime->no_period_wakeup)
1926 		wait_time = MAX_SCHEDULE_TIMEOUT;
1927 	else {
1928 		wait_time = 10;
1929 		if (runtime->rate) {
1930 			long t = runtime->period_size * 2 / runtime->rate;
1931 			wait_time = max(t, wait_time);
1932 		}
1933 		wait_time = msecs_to_jiffies(wait_time * 1000);
1934 	}
1935 
1936 	for (;;) {
1937 		if (signal_pending(current)) {
1938 			err = -ERESTARTSYS;
1939 			break;
1940 		}
1941 
1942 		/*
1943 		 * We need to check if space became available already
1944 		 * (and thus the wakeup happened already) first to close
1945 		 * the race of space already having become available.
1946 		 * This check must happen after been added to the waitqueue
1947 		 * and having current state be INTERRUPTIBLE.
1948 		 */
1949 		if (is_playback)
1950 			avail = snd_pcm_playback_avail(runtime);
1951 		else
1952 			avail = snd_pcm_capture_avail(runtime);
1953 		if (avail >= runtime->twake)
1954 			break;
1955 		snd_pcm_stream_unlock_irq(substream);
1956 
1957 		tout = schedule_timeout(wait_time);
1958 
1959 		snd_pcm_stream_lock_irq(substream);
1960 		set_current_state(TASK_INTERRUPTIBLE);
1961 		switch (runtime->status->state) {
1962 		case SNDRV_PCM_STATE_SUSPENDED:
1963 			err = -ESTRPIPE;
1964 			goto _endloop;
1965 		case SNDRV_PCM_STATE_XRUN:
1966 			err = -EPIPE;
1967 			goto _endloop;
1968 		case SNDRV_PCM_STATE_DRAINING:
1969 			if (is_playback)
1970 				err = -EPIPE;
1971 			else
1972 				avail = 0; /* indicate draining */
1973 			goto _endloop;
1974 		case SNDRV_PCM_STATE_OPEN:
1975 		case SNDRV_PCM_STATE_SETUP:
1976 		case SNDRV_PCM_STATE_DISCONNECTED:
1977 			err = -EBADFD;
1978 			goto _endloop;
1979 		case SNDRV_PCM_STATE_PAUSED:
1980 			continue;
1981 		}
1982 		if (!tout) {
1983 			pcm_dbg(substream->pcm,
1984 				"%s write error (DMA or IRQ trouble?)\n",
1985 				is_playback ? "playback" : "capture");
1986 			err = -EIO;
1987 			break;
1988 		}
1989 	}
1990  _endloop:
1991 	set_current_state(TASK_RUNNING);
1992 	remove_wait_queue(&runtime->tsleep, &wait);
1993 	*availp = avail;
1994 	return err;
1995 }
1996 
snd_pcm_lib_write_transfer(struct snd_pcm_substream * substream,unsigned int hwoff,unsigned long data,unsigned int off,snd_pcm_uframes_t frames)1997 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1998 				      unsigned int hwoff,
1999 				      unsigned long data, unsigned int off,
2000 				      snd_pcm_uframes_t frames)
2001 {
2002 	struct snd_pcm_runtime *runtime = substream->runtime;
2003 	int err;
2004 	char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2005 	if (substream->ops->copy) {
2006 		if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2007 			return err;
2008 	} else {
2009 		char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2010 		if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
2011 			return -EFAULT;
2012 	}
2013 	return 0;
2014 }
2015 
2016 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
2017 			  unsigned long data, unsigned int off,
2018 			  snd_pcm_uframes_t size);
2019 
snd_pcm_lib_write1(struct snd_pcm_substream * substream,unsigned long data,snd_pcm_uframes_t size,int nonblock,transfer_f transfer)2020 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
2021 					    unsigned long data,
2022 					    snd_pcm_uframes_t size,
2023 					    int nonblock,
2024 					    transfer_f transfer)
2025 {
2026 	struct snd_pcm_runtime *runtime = substream->runtime;
2027 	snd_pcm_uframes_t xfer = 0;
2028 	snd_pcm_uframes_t offset = 0;
2029 	snd_pcm_uframes_t avail;
2030 	int err = 0;
2031 
2032 	if (size == 0)
2033 		return 0;
2034 
2035 	snd_pcm_stream_lock_irq(substream);
2036 	switch (runtime->status->state) {
2037 	case SNDRV_PCM_STATE_PREPARED:
2038 	case SNDRV_PCM_STATE_RUNNING:
2039 	case SNDRV_PCM_STATE_PAUSED:
2040 		break;
2041 	case SNDRV_PCM_STATE_XRUN:
2042 		err = -EPIPE;
2043 		goto _end_unlock;
2044 	case SNDRV_PCM_STATE_SUSPENDED:
2045 		err = -ESTRPIPE;
2046 		goto _end_unlock;
2047 	default:
2048 		err = -EBADFD;
2049 		goto _end_unlock;
2050 	}
2051 
2052 	runtime->twake = runtime->control->avail_min ? : 1;
2053 	if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2054 		snd_pcm_update_hw_ptr(substream);
2055 	avail = snd_pcm_playback_avail(runtime);
2056 	while (size > 0) {
2057 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2058 		snd_pcm_uframes_t cont;
2059 		if (!avail) {
2060 			if (nonblock) {
2061 				err = -EAGAIN;
2062 				goto _end_unlock;
2063 			}
2064 			runtime->twake = min_t(snd_pcm_uframes_t, size,
2065 					runtime->control->avail_min ? : 1);
2066 			err = wait_for_avail(substream, &avail);
2067 			if (err < 0)
2068 				goto _end_unlock;
2069 		}
2070 		frames = size > avail ? avail : size;
2071 		cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2072 		if (frames > cont)
2073 			frames = cont;
2074 		if (snd_BUG_ON(!frames)) {
2075 			runtime->twake = 0;
2076 			snd_pcm_stream_unlock_irq(substream);
2077 			return -EINVAL;
2078 		}
2079 		appl_ptr = runtime->control->appl_ptr;
2080 		appl_ofs = appl_ptr % runtime->buffer_size;
2081 		snd_pcm_stream_unlock_irq(substream);
2082 		err = transfer(substream, appl_ofs, data, offset, frames);
2083 		snd_pcm_stream_lock_irq(substream);
2084 		if (err < 0)
2085 			goto _end_unlock;
2086 		switch (runtime->status->state) {
2087 		case SNDRV_PCM_STATE_XRUN:
2088 			err = -EPIPE;
2089 			goto _end_unlock;
2090 		case SNDRV_PCM_STATE_SUSPENDED:
2091 			err = -ESTRPIPE;
2092 			goto _end_unlock;
2093 		default:
2094 			break;
2095 		}
2096 		appl_ptr += frames;
2097 		if (appl_ptr >= runtime->boundary)
2098 			appl_ptr -= runtime->boundary;
2099 		runtime->control->appl_ptr = appl_ptr;
2100 		if (substream->ops->ack)
2101 			substream->ops->ack(substream);
2102 
2103 		offset += frames;
2104 		size -= frames;
2105 		xfer += frames;
2106 		avail -= frames;
2107 		if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2108 		    snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2109 			err = snd_pcm_start(substream);
2110 			if (err < 0)
2111 				goto _end_unlock;
2112 		}
2113 	}
2114  _end_unlock:
2115 	runtime->twake = 0;
2116 	if (xfer > 0 && err >= 0)
2117 		snd_pcm_update_state(substream, runtime);
2118 	snd_pcm_stream_unlock_irq(substream);
2119 	return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2120 }
2121 
2122 /* sanity-check for read/write methods */
pcm_sanity_check(struct snd_pcm_substream * substream)2123 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2124 {
2125 	struct snd_pcm_runtime *runtime;
2126 	if (PCM_RUNTIME_CHECK(substream))
2127 		return -ENXIO;
2128 	runtime = substream->runtime;
2129 	if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
2130 		return -EINVAL;
2131 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2132 		return -EBADFD;
2133 	return 0;
2134 }
2135 
snd_pcm_lib_write(struct snd_pcm_substream * substream,const void __user * buf,snd_pcm_uframes_t size)2136 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
2137 {
2138 	struct snd_pcm_runtime *runtime;
2139 	int nonblock;
2140 	int err;
2141 
2142 	err = pcm_sanity_check(substream);
2143 	if (err < 0)
2144 		return err;
2145 	runtime = substream->runtime;
2146 	nonblock = !!(substream->f_flags & O_NONBLOCK);
2147 
2148 	if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2149 	    runtime->channels > 1)
2150 		return -EINVAL;
2151 	return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
2152 				  snd_pcm_lib_write_transfer);
2153 }
2154 
2155 EXPORT_SYMBOL(snd_pcm_lib_write);
2156 
snd_pcm_lib_writev_transfer(struct snd_pcm_substream * substream,unsigned int hwoff,unsigned long data,unsigned int off,snd_pcm_uframes_t frames)2157 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
2158 				       unsigned int hwoff,
2159 				       unsigned long data, unsigned int off,
2160 				       snd_pcm_uframes_t frames)
2161 {
2162 	struct snd_pcm_runtime *runtime = substream->runtime;
2163 	int err;
2164 	void __user **bufs = (void __user **)data;
2165 	int channels = runtime->channels;
2166 	int c;
2167 	if (substream->ops->copy) {
2168 		if (snd_BUG_ON(!substream->ops->silence))
2169 			return -EINVAL;
2170 		for (c = 0; c < channels; ++c, ++bufs) {
2171 			if (*bufs == NULL) {
2172 				if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
2173 					return err;
2174 			} else {
2175 				char __user *buf = *bufs + samples_to_bytes(runtime, off);
2176 				if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2177 					return err;
2178 			}
2179 		}
2180 	} else {
2181 		/* default transfer behaviour */
2182 		size_t dma_csize = runtime->dma_bytes / channels;
2183 		for (c = 0; c < channels; ++c, ++bufs) {
2184 			char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2185 			if (*bufs == NULL) {
2186 				snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
2187 			} else {
2188 				char __user *buf = *bufs + samples_to_bytes(runtime, off);
2189 				if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
2190 					return -EFAULT;
2191 			}
2192 		}
2193 	}
2194 	return 0;
2195 }
2196 
snd_pcm_lib_writev(struct snd_pcm_substream * substream,void __user ** bufs,snd_pcm_uframes_t frames)2197 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
2198 				     void __user **bufs,
2199 				     snd_pcm_uframes_t frames)
2200 {
2201 	struct snd_pcm_runtime *runtime;
2202 	int nonblock;
2203 	int err;
2204 
2205 	err = pcm_sanity_check(substream);
2206 	if (err < 0)
2207 		return err;
2208 	runtime = substream->runtime;
2209 	nonblock = !!(substream->f_flags & O_NONBLOCK);
2210 
2211 	if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2212 		return -EINVAL;
2213 	return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2214 				  nonblock, snd_pcm_lib_writev_transfer);
2215 }
2216 
2217 EXPORT_SYMBOL(snd_pcm_lib_writev);
2218 
snd_pcm_lib_read_transfer(struct snd_pcm_substream * substream,unsigned int hwoff,unsigned long data,unsigned int off,snd_pcm_uframes_t frames)2219 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
2220 				     unsigned int hwoff,
2221 				     unsigned long data, unsigned int off,
2222 				     snd_pcm_uframes_t frames)
2223 {
2224 	struct snd_pcm_runtime *runtime = substream->runtime;
2225 	int err;
2226 	char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2227 	if (substream->ops->copy) {
2228 		if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2229 			return err;
2230 	} else {
2231 		char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2232 		if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2233 			return -EFAULT;
2234 	}
2235 	return 0;
2236 }
2237 
snd_pcm_lib_read1(struct snd_pcm_substream * substream,unsigned long data,snd_pcm_uframes_t size,int nonblock,transfer_f transfer)2238 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2239 					   unsigned long data,
2240 					   snd_pcm_uframes_t size,
2241 					   int nonblock,
2242 					   transfer_f transfer)
2243 {
2244 	struct snd_pcm_runtime *runtime = substream->runtime;
2245 	snd_pcm_uframes_t xfer = 0;
2246 	snd_pcm_uframes_t offset = 0;
2247 	snd_pcm_uframes_t avail;
2248 	int err = 0;
2249 
2250 	if (size == 0)
2251 		return 0;
2252 
2253 	snd_pcm_stream_lock_irq(substream);
2254 	switch (runtime->status->state) {
2255 	case SNDRV_PCM_STATE_PREPARED:
2256 		if (size >= runtime->start_threshold) {
2257 			err = snd_pcm_start(substream);
2258 			if (err < 0)
2259 				goto _end_unlock;
2260 		}
2261 		break;
2262 	case SNDRV_PCM_STATE_DRAINING:
2263 	case SNDRV_PCM_STATE_RUNNING:
2264 	case SNDRV_PCM_STATE_PAUSED:
2265 		break;
2266 	case SNDRV_PCM_STATE_XRUN:
2267 		err = -EPIPE;
2268 		goto _end_unlock;
2269 	case SNDRV_PCM_STATE_SUSPENDED:
2270 		err = -ESTRPIPE;
2271 		goto _end_unlock;
2272 	default:
2273 		err = -EBADFD;
2274 		goto _end_unlock;
2275 	}
2276 
2277 	runtime->twake = runtime->control->avail_min ? : 1;
2278 	if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2279 		snd_pcm_update_hw_ptr(substream);
2280 	avail = snd_pcm_capture_avail(runtime);
2281 	while (size > 0) {
2282 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2283 		snd_pcm_uframes_t cont;
2284 		if (!avail) {
2285 			if (runtime->status->state ==
2286 			    SNDRV_PCM_STATE_DRAINING) {
2287 				snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2288 				goto _end_unlock;
2289 			}
2290 			if (nonblock) {
2291 				err = -EAGAIN;
2292 				goto _end_unlock;
2293 			}
2294 			runtime->twake = min_t(snd_pcm_uframes_t, size,
2295 					runtime->control->avail_min ? : 1);
2296 			err = wait_for_avail(substream, &avail);
2297 			if (err < 0)
2298 				goto _end_unlock;
2299 			if (!avail)
2300 				continue; /* draining */
2301 		}
2302 		frames = size > avail ? avail : size;
2303 		cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2304 		if (frames > cont)
2305 			frames = cont;
2306 		if (snd_BUG_ON(!frames)) {
2307 			runtime->twake = 0;
2308 			snd_pcm_stream_unlock_irq(substream);
2309 			return -EINVAL;
2310 		}
2311 		appl_ptr = runtime->control->appl_ptr;
2312 		appl_ofs = appl_ptr % runtime->buffer_size;
2313 		snd_pcm_stream_unlock_irq(substream);
2314 		err = transfer(substream, appl_ofs, data, offset, frames);
2315 		snd_pcm_stream_lock_irq(substream);
2316 		if (err < 0)
2317 			goto _end_unlock;
2318 		switch (runtime->status->state) {
2319 		case SNDRV_PCM_STATE_XRUN:
2320 			err = -EPIPE;
2321 			goto _end_unlock;
2322 		case SNDRV_PCM_STATE_SUSPENDED:
2323 			err = -ESTRPIPE;
2324 			goto _end_unlock;
2325 		default:
2326 			break;
2327 		}
2328 		appl_ptr += frames;
2329 		if (appl_ptr >= runtime->boundary)
2330 			appl_ptr -= runtime->boundary;
2331 		runtime->control->appl_ptr = appl_ptr;
2332 		if (substream->ops->ack)
2333 			substream->ops->ack(substream);
2334 
2335 		offset += frames;
2336 		size -= frames;
2337 		xfer += frames;
2338 		avail -= frames;
2339 	}
2340  _end_unlock:
2341 	runtime->twake = 0;
2342 	if (xfer > 0 && err >= 0)
2343 		snd_pcm_update_state(substream, runtime);
2344 	snd_pcm_stream_unlock_irq(substream);
2345 	return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2346 }
2347 
snd_pcm_lib_read(struct snd_pcm_substream * substream,void __user * buf,snd_pcm_uframes_t size)2348 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2349 {
2350 	struct snd_pcm_runtime *runtime;
2351 	int nonblock;
2352 	int err;
2353 
2354 	err = pcm_sanity_check(substream);
2355 	if (err < 0)
2356 		return err;
2357 	runtime = substream->runtime;
2358 	nonblock = !!(substream->f_flags & O_NONBLOCK);
2359 	if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2360 		return -EINVAL;
2361 	return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2362 }
2363 
2364 EXPORT_SYMBOL(snd_pcm_lib_read);
2365 
snd_pcm_lib_readv_transfer(struct snd_pcm_substream * substream,unsigned int hwoff,unsigned long data,unsigned int off,snd_pcm_uframes_t frames)2366 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2367 				      unsigned int hwoff,
2368 				      unsigned long data, unsigned int off,
2369 				      snd_pcm_uframes_t frames)
2370 {
2371 	struct snd_pcm_runtime *runtime = substream->runtime;
2372 	int err;
2373 	void __user **bufs = (void __user **)data;
2374 	int channels = runtime->channels;
2375 	int c;
2376 	if (substream->ops->copy) {
2377 		for (c = 0; c < channels; ++c, ++bufs) {
2378 			char __user *buf;
2379 			if (*bufs == NULL)
2380 				continue;
2381 			buf = *bufs + samples_to_bytes(runtime, off);
2382 			if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2383 				return err;
2384 		}
2385 	} else {
2386 		snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2387 		for (c = 0; c < channels; ++c, ++bufs) {
2388 			char *hwbuf;
2389 			char __user *buf;
2390 			if (*bufs == NULL)
2391 				continue;
2392 
2393 			hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2394 			buf = *bufs + samples_to_bytes(runtime, off);
2395 			if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2396 				return -EFAULT;
2397 		}
2398 	}
2399 	return 0;
2400 }
2401 
snd_pcm_lib_readv(struct snd_pcm_substream * substream,void __user ** bufs,snd_pcm_uframes_t frames)2402 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2403 				    void __user **bufs,
2404 				    snd_pcm_uframes_t frames)
2405 {
2406 	struct snd_pcm_runtime *runtime;
2407 	int nonblock;
2408 	int err;
2409 
2410 	err = pcm_sanity_check(substream);
2411 	if (err < 0)
2412 		return err;
2413 	runtime = substream->runtime;
2414 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2415 		return -EBADFD;
2416 
2417 	nonblock = !!(substream->f_flags & O_NONBLOCK);
2418 	if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2419 		return -EINVAL;
2420 	return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2421 }
2422 
2423 EXPORT_SYMBOL(snd_pcm_lib_readv);
2424 
2425 /*
2426  * standard channel mapping helpers
2427  */
2428 
2429 /* default channel maps for multi-channel playbacks, up to 8 channels */
2430 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2431 	{ .channels = 1,
2432 	  .map = { SNDRV_CHMAP_MONO } },
2433 	{ .channels = 2,
2434 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2435 	{ .channels = 4,
2436 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2437 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2438 	{ .channels = 6,
2439 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2440 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2441 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2442 	{ .channels = 8,
2443 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2444 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2445 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2446 		   SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2447 	{ }
2448 };
2449 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2450 
2451 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2452 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2453 	{ .channels = 1,
2454 	  .map = { SNDRV_CHMAP_MONO } },
2455 	{ .channels = 2,
2456 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2457 	{ .channels = 4,
2458 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2459 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2460 	{ .channels = 6,
2461 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2462 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2463 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2464 	{ .channels = 8,
2465 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2466 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2467 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2468 		   SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2469 	{ }
2470 };
2471 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2472 
valid_chmap_channels(const struct snd_pcm_chmap * info,int ch)2473 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2474 {
2475 	if (ch > info->max_channels)
2476 		return false;
2477 	return !info->channel_mask || (info->channel_mask & (1U << ch));
2478 }
2479 
pcm_chmap_ctl_info(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_info * uinfo)2480 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2481 			      struct snd_ctl_elem_info *uinfo)
2482 {
2483 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2484 
2485 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2486 	uinfo->count = 0;
2487 	uinfo->count = info->max_channels;
2488 	uinfo->value.integer.min = 0;
2489 	uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2490 	return 0;
2491 }
2492 
2493 /* get callback for channel map ctl element
2494  * stores the channel position firstly matching with the current channels
2495  */
pcm_chmap_ctl_get(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_value * ucontrol)2496 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2497 			     struct snd_ctl_elem_value *ucontrol)
2498 {
2499 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2500 	unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2501 	struct snd_pcm_substream *substream;
2502 	const struct snd_pcm_chmap_elem *map;
2503 
2504 	if (snd_BUG_ON(!info->chmap))
2505 		return -EINVAL;
2506 	substream = snd_pcm_chmap_substream(info, idx);
2507 	if (!substream)
2508 		return -ENODEV;
2509 	memset(ucontrol->value.integer.value, 0,
2510 	       sizeof(ucontrol->value.integer.value));
2511 	if (!substream->runtime)
2512 		return 0; /* no channels set */
2513 	for (map = info->chmap; map->channels; map++) {
2514 		int i;
2515 		if (map->channels == substream->runtime->channels &&
2516 		    valid_chmap_channels(info, map->channels)) {
2517 			for (i = 0; i < map->channels; i++)
2518 				ucontrol->value.integer.value[i] = map->map[i];
2519 			return 0;
2520 		}
2521 	}
2522 	return -EINVAL;
2523 }
2524 
2525 /* tlv callback for channel map ctl element
2526  * expands the pre-defined channel maps in a form of TLV
2527  */
pcm_chmap_ctl_tlv(struct snd_kcontrol * kcontrol,int op_flag,unsigned int size,unsigned int __user * tlv)2528 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2529 			     unsigned int size, unsigned int __user *tlv)
2530 {
2531 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2532 	const struct snd_pcm_chmap_elem *map;
2533 	unsigned int __user *dst;
2534 	int c, count = 0;
2535 
2536 	if (snd_BUG_ON(!info->chmap))
2537 		return -EINVAL;
2538 	if (size < 8)
2539 		return -ENOMEM;
2540 	if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2541 		return -EFAULT;
2542 	size -= 8;
2543 	dst = tlv + 2;
2544 	for (map = info->chmap; map->channels; map++) {
2545 		int chs_bytes = map->channels * 4;
2546 		if (!valid_chmap_channels(info, map->channels))
2547 			continue;
2548 		if (size < 8)
2549 			return -ENOMEM;
2550 		if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2551 		    put_user(chs_bytes, dst + 1))
2552 			return -EFAULT;
2553 		dst += 2;
2554 		size -= 8;
2555 		count += 8;
2556 		if (size < chs_bytes)
2557 			return -ENOMEM;
2558 		size -= chs_bytes;
2559 		count += chs_bytes;
2560 		for (c = 0; c < map->channels; c++) {
2561 			if (put_user(map->map[c], dst))
2562 				return -EFAULT;
2563 			dst++;
2564 		}
2565 	}
2566 	if (put_user(count, tlv + 1))
2567 		return -EFAULT;
2568 	return 0;
2569 }
2570 
pcm_chmap_ctl_private_free(struct snd_kcontrol * kcontrol)2571 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2572 {
2573 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2574 	info->pcm->streams[info->stream].chmap_kctl = NULL;
2575 	kfree(info);
2576 }
2577 
2578 /**
2579  * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2580  * @pcm: the assigned PCM instance
2581  * @stream: stream direction
2582  * @chmap: channel map elements (for query)
2583  * @max_channels: the max number of channels for the stream
2584  * @private_value: the value passed to each kcontrol's private_value field
2585  * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2586  *
2587  * Create channel-mapping control elements assigned to the given PCM stream(s).
2588  * Return: Zero if successful, or a negative error value.
2589  */
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)2590 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2591 			   const struct snd_pcm_chmap_elem *chmap,
2592 			   int max_channels,
2593 			   unsigned long private_value,
2594 			   struct snd_pcm_chmap **info_ret)
2595 {
2596 	struct snd_pcm_chmap *info;
2597 	struct snd_kcontrol_new knew = {
2598 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
2599 		.access = SNDRV_CTL_ELEM_ACCESS_READ |
2600 			SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2601 			SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2602 		.info = pcm_chmap_ctl_info,
2603 		.get = pcm_chmap_ctl_get,
2604 		.tlv.c = pcm_chmap_ctl_tlv,
2605 	};
2606 	int err;
2607 
2608 	info = kzalloc(sizeof(*info), GFP_KERNEL);
2609 	if (!info)
2610 		return -ENOMEM;
2611 	info->pcm = pcm;
2612 	info->stream = stream;
2613 	info->chmap = chmap;
2614 	info->max_channels = max_channels;
2615 	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2616 		knew.name = "Playback Channel Map";
2617 	else
2618 		knew.name = "Capture Channel Map";
2619 	knew.device = pcm->device;
2620 	knew.count = pcm->streams[stream].substream_count;
2621 	knew.private_value = private_value;
2622 	info->kctl = snd_ctl_new1(&knew, info);
2623 	if (!info->kctl) {
2624 		kfree(info);
2625 		return -ENOMEM;
2626 	}
2627 	info->kctl->private_free = pcm_chmap_ctl_private_free;
2628 	err = snd_ctl_add(pcm->card, info->kctl);
2629 	if (err < 0)
2630 		return err;
2631 	pcm->streams[stream].chmap_kctl = info->kctl;
2632 	if (info_ret)
2633 		*info_ret = info;
2634 	return 0;
2635 }
2636 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);
2637