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1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Digital Audio (PCM) abstract layer
4  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5  *                   Abramo Bagnara <abramo@alsa-project.org>
6  */
7 
8 #include <linux/slab.h>
9 #include <linux/sched/signal.h>
10 #include <linux/time.h>
11 #include <linux/math64.h>
12 #include <linux/export.h>
13 #include <sound/core.h>
14 #include <sound/control.h>
15 #include <sound/tlv.h>
16 #include <sound/info.h>
17 #include <sound/pcm.h>
18 #include <sound/pcm_params.h>
19 #include <sound/timer.h>
20 
21 #include "pcm_local.h"
22 
23 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
24 #define CREATE_TRACE_POINTS
25 #include "pcm_trace.h"
26 #else
27 #define trace_hwptr(substream, pos, in_interrupt)
28 #define trace_xrun(substream)
29 #define trace_hw_ptr_error(substream, reason)
30 #define trace_applptr(substream, prev, curr)
31 #endif
32 
33 static int fill_silence_frames(struct snd_pcm_substream *substream,
34 			       snd_pcm_uframes_t off, snd_pcm_uframes_t frames);
35 
36 /*
37  * fill ring buffer with silence
38  * runtime->silence_start: starting pointer to silence area
39  * runtime->silence_filled: size filled with silence
40  * runtime->silence_threshold: threshold from application
41  * runtime->silence_size: maximal size from application
42  *
43  * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
44  */
snd_pcm_playback_silence(struct snd_pcm_substream * substream,snd_pcm_uframes_t new_hw_ptr)45 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
46 {
47 	struct snd_pcm_runtime *runtime = substream->runtime;
48 	snd_pcm_uframes_t frames, ofs, transfer;
49 	int err;
50 
51 	if (runtime->silence_size < runtime->boundary) {
52 		snd_pcm_sframes_t noise_dist, n;
53 		snd_pcm_uframes_t appl_ptr = READ_ONCE(runtime->control->appl_ptr);
54 		if (runtime->silence_start != appl_ptr) {
55 			n = appl_ptr - runtime->silence_start;
56 			if (n < 0)
57 				n += runtime->boundary;
58 			if ((snd_pcm_uframes_t)n < runtime->silence_filled)
59 				runtime->silence_filled -= n;
60 			else
61 				runtime->silence_filled = 0;
62 			runtime->silence_start = appl_ptr;
63 		}
64 		if (runtime->silence_filled >= runtime->buffer_size)
65 			return;
66 		noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
67 		if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
68 			return;
69 		frames = runtime->silence_threshold - noise_dist;
70 		if (frames > runtime->silence_size)
71 			frames = runtime->silence_size;
72 	} else {
73 		if (new_hw_ptr == ULONG_MAX) {	/* initialization */
74 			snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
75 			if (avail > runtime->buffer_size)
76 				avail = runtime->buffer_size;
77 			runtime->silence_filled = avail > 0 ? avail : 0;
78 			runtime->silence_start = (runtime->status->hw_ptr +
79 						  runtime->silence_filled) %
80 						 runtime->boundary;
81 		} else {
82 			ofs = runtime->status->hw_ptr;
83 			frames = new_hw_ptr - ofs;
84 			if ((snd_pcm_sframes_t)frames < 0)
85 				frames += runtime->boundary;
86 			runtime->silence_filled -= frames;
87 			if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
88 				runtime->silence_filled = 0;
89 				runtime->silence_start = new_hw_ptr;
90 			} else {
91 				runtime->silence_start = ofs;
92 			}
93 		}
94 		frames = runtime->buffer_size - runtime->silence_filled;
95 	}
96 	if (snd_BUG_ON(frames > runtime->buffer_size))
97 		return;
98 	if (frames == 0)
99 		return;
100 	ofs = runtime->silence_start % runtime->buffer_size;
101 	while (frames > 0) {
102 		transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
103 		err = fill_silence_frames(substream, ofs, transfer);
104 		snd_BUG_ON(err < 0);
105 		runtime->silence_filled += transfer;
106 		frames -= transfer;
107 		ofs = 0;
108 	}
109 }
110 
111 #ifdef CONFIG_SND_DEBUG
snd_pcm_debug_name(struct snd_pcm_substream * substream,char * name,size_t len)112 void snd_pcm_debug_name(struct snd_pcm_substream *substream,
113 			   char *name, size_t len)
114 {
115 	snprintf(name, len, "pcmC%dD%d%c:%d",
116 		 substream->pcm->card->number,
117 		 substream->pcm->device,
118 		 substream->stream ? 'c' : 'p',
119 		 substream->number);
120 }
121 EXPORT_SYMBOL(snd_pcm_debug_name);
122 #endif
123 
124 #define XRUN_DEBUG_BASIC	(1<<0)
125 #define XRUN_DEBUG_STACK	(1<<1)	/* dump also stack */
126 #define XRUN_DEBUG_JIFFIESCHECK	(1<<2)	/* do jiffies check */
127 
128 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
129 
130 #define xrun_debug(substream, mask) \
131 			((substream)->pstr->xrun_debug & (mask))
132 #else
133 #define xrun_debug(substream, mask)	0
134 #endif
135 
136 #define dump_stack_on_xrun(substream) do {			\
137 		if (xrun_debug(substream, XRUN_DEBUG_STACK))	\
138 			dump_stack();				\
139 	} while (0)
140 
141 /* call with stream lock held */
__snd_pcm_xrun(struct snd_pcm_substream * substream)142 void __snd_pcm_xrun(struct snd_pcm_substream *substream)
143 {
144 	struct snd_pcm_runtime *runtime = substream->runtime;
145 
146 	trace_xrun(substream);
147 	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
148 		snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
149 	snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
150 	if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
151 		char name[16];
152 		snd_pcm_debug_name(substream, name, sizeof(name));
153 		pcm_warn(substream->pcm, "XRUN: %s\n", name);
154 		dump_stack_on_xrun(substream);
155 	}
156 }
157 
158 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
159 #define hw_ptr_error(substream, in_interrupt, reason, fmt, args...)	\
160 	do {								\
161 		trace_hw_ptr_error(substream, reason);	\
162 		if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {		\
163 			pr_err_ratelimited("ALSA: PCM: [%c] " reason ": " fmt, \
164 					   (in_interrupt) ? 'Q' : 'P', ##args);	\
165 			dump_stack_on_xrun(substream);			\
166 		}							\
167 	} while (0)
168 
169 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
170 
171 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
172 
173 #endif
174 
snd_pcm_update_state(struct snd_pcm_substream * substream,struct snd_pcm_runtime * runtime)175 int snd_pcm_update_state(struct snd_pcm_substream *substream,
176 			 struct snd_pcm_runtime *runtime)
177 {
178 	snd_pcm_uframes_t avail;
179 
180 	avail = snd_pcm_avail(substream);
181 	if (avail > runtime->avail_max)
182 		runtime->avail_max = avail;
183 	if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
184 		if (avail >= runtime->buffer_size) {
185 			snd_pcm_drain_done(substream);
186 			return -EPIPE;
187 		}
188 	} else {
189 		if (avail >= runtime->stop_threshold) {
190 			__snd_pcm_xrun(substream);
191 			return -EPIPE;
192 		}
193 	}
194 	if (runtime->twake) {
195 		if (avail >= runtime->twake)
196 			wake_up(&runtime->tsleep);
197 	} else if (avail >= runtime->control->avail_min)
198 		wake_up(&runtime->sleep);
199 	return 0;
200 }
201 
update_audio_tstamp(struct snd_pcm_substream * substream,struct timespec * curr_tstamp,struct timespec * audio_tstamp)202 static void update_audio_tstamp(struct snd_pcm_substream *substream,
203 				struct timespec *curr_tstamp,
204 				struct timespec *audio_tstamp)
205 {
206 	struct snd_pcm_runtime *runtime = substream->runtime;
207 	u64 audio_frames, audio_nsecs;
208 	struct timespec driver_tstamp;
209 
210 	if (runtime->tstamp_mode != SNDRV_PCM_TSTAMP_ENABLE)
211 		return;
212 
213 	if (!(substream->ops->get_time_info) ||
214 		(runtime->audio_tstamp_report.actual_type ==
215 			SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
216 
217 		/*
218 		 * provide audio timestamp derived from pointer position
219 		 * add delay only if requested
220 		 */
221 
222 		audio_frames = runtime->hw_ptr_wrap + runtime->status->hw_ptr;
223 
224 		if (runtime->audio_tstamp_config.report_delay) {
225 			if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
226 				audio_frames -=  runtime->delay;
227 			else
228 				audio_frames +=  runtime->delay;
229 		}
230 		audio_nsecs = div_u64(audio_frames * 1000000000LL,
231 				runtime->rate);
232 		*audio_tstamp = ns_to_timespec(audio_nsecs);
233 	}
234 	if (!timespec_equal(&runtime->status->audio_tstamp, audio_tstamp)) {
235 		runtime->status->audio_tstamp = *audio_tstamp;
236 		runtime->status->tstamp = *curr_tstamp;
237 	}
238 
239 	/*
240 	 * re-take a driver timestamp to let apps detect if the reference tstamp
241 	 * read by low-level hardware was provided with a delay
242 	 */
243 	snd_pcm_gettime(substream->runtime, (struct timespec *)&driver_tstamp);
244 	runtime->driver_tstamp = driver_tstamp;
245 }
246 
snd_pcm_update_hw_ptr0(struct snd_pcm_substream * substream,unsigned int in_interrupt)247 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
248 				  unsigned int in_interrupt)
249 {
250 	struct snd_pcm_runtime *runtime = substream->runtime;
251 	snd_pcm_uframes_t pos;
252 	snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
253 	snd_pcm_sframes_t hdelta, delta;
254 	unsigned long jdelta;
255 	unsigned long curr_jiffies;
256 	struct timespec curr_tstamp;
257 	struct timespec audio_tstamp;
258 	int crossed_boundary = 0;
259 
260 	old_hw_ptr = runtime->status->hw_ptr;
261 
262 	/*
263 	 * group pointer, time and jiffies reads to allow for more
264 	 * accurate correlations/corrections.
265 	 * The values are stored at the end of this routine after
266 	 * corrections for hw_ptr position
267 	 */
268 	pos = substream->ops->pointer(substream);
269 	curr_jiffies = jiffies;
270 	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
271 		if ((substream->ops->get_time_info) &&
272 			(runtime->audio_tstamp_config.type_requested != SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
273 			substream->ops->get_time_info(substream, &curr_tstamp,
274 						&audio_tstamp,
275 						&runtime->audio_tstamp_config,
276 						&runtime->audio_tstamp_report);
277 
278 			/* re-test in case tstamp type is not supported in hardware and was demoted to DEFAULT */
279 			if (runtime->audio_tstamp_report.actual_type == SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)
280 				snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
281 		} else
282 			snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
283 	}
284 
285 	if (pos == SNDRV_PCM_POS_XRUN) {
286 		__snd_pcm_xrun(substream);
287 		return -EPIPE;
288 	}
289 	if (pos >= runtime->buffer_size) {
290 		if (printk_ratelimit()) {
291 			char name[16];
292 			snd_pcm_debug_name(substream, name, sizeof(name));
293 			pcm_err(substream->pcm,
294 				"invalid position: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
295 				name, pos, runtime->buffer_size,
296 				runtime->period_size);
297 		}
298 		pos = 0;
299 	}
300 	pos -= pos % runtime->min_align;
301 	trace_hwptr(substream, pos, in_interrupt);
302 	hw_base = runtime->hw_ptr_base;
303 	new_hw_ptr = hw_base + pos;
304 	if (in_interrupt) {
305 		/* we know that one period was processed */
306 		/* delta = "expected next hw_ptr" for in_interrupt != 0 */
307 		delta = runtime->hw_ptr_interrupt + runtime->period_size;
308 		if (delta > new_hw_ptr) {
309 			/* check for double acknowledged interrupts */
310 			hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
311 			if (hdelta > runtime->hw_ptr_buffer_jiffies/2 + 1) {
312 				hw_base += runtime->buffer_size;
313 				if (hw_base >= runtime->boundary) {
314 					hw_base = 0;
315 					crossed_boundary++;
316 				}
317 				new_hw_ptr = hw_base + pos;
318 				goto __delta;
319 			}
320 		}
321 	}
322 	/* new_hw_ptr might be lower than old_hw_ptr in case when */
323 	/* pointer crosses the end of the ring buffer */
324 	if (new_hw_ptr < old_hw_ptr) {
325 		hw_base += runtime->buffer_size;
326 		if (hw_base >= runtime->boundary) {
327 			hw_base = 0;
328 			crossed_boundary++;
329 		}
330 		new_hw_ptr = hw_base + pos;
331 	}
332       __delta:
333 	delta = new_hw_ptr - old_hw_ptr;
334 	if (delta < 0)
335 		delta += runtime->boundary;
336 
337 	if (runtime->no_period_wakeup) {
338 		snd_pcm_sframes_t xrun_threshold;
339 		/*
340 		 * Without regular period interrupts, we have to check
341 		 * the elapsed time to detect xruns.
342 		 */
343 		jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
344 		if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
345 			goto no_delta_check;
346 		hdelta = jdelta - delta * HZ / runtime->rate;
347 		xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
348 		while (hdelta > xrun_threshold) {
349 			delta += runtime->buffer_size;
350 			hw_base += runtime->buffer_size;
351 			if (hw_base >= runtime->boundary) {
352 				hw_base = 0;
353 				crossed_boundary++;
354 			}
355 			new_hw_ptr = hw_base + pos;
356 			hdelta -= runtime->hw_ptr_buffer_jiffies;
357 		}
358 		goto no_delta_check;
359 	}
360 
361 	/* something must be really wrong */
362 	if (delta >= runtime->buffer_size + runtime->period_size) {
363 		hw_ptr_error(substream, in_interrupt, "Unexpected hw_ptr",
364 			     "(stream=%i, pos=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
365 			     substream->stream, (long)pos,
366 			     (long)new_hw_ptr, (long)old_hw_ptr);
367 		return 0;
368 	}
369 
370 	/* Do jiffies check only in xrun_debug mode */
371 	if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
372 		goto no_jiffies_check;
373 
374 	/* Skip the jiffies check for hardwares with BATCH flag.
375 	 * Such hardware usually just increases the position at each IRQ,
376 	 * thus it can't give any strange position.
377 	 */
378 	if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
379 		goto no_jiffies_check;
380 	hdelta = delta;
381 	if (hdelta < runtime->delay)
382 		goto no_jiffies_check;
383 	hdelta -= runtime->delay;
384 	jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
385 	if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
386 		delta = jdelta /
387 			(((runtime->period_size * HZ) / runtime->rate)
388 								+ HZ/100);
389 		/* move new_hw_ptr according jiffies not pos variable */
390 		new_hw_ptr = old_hw_ptr;
391 		hw_base = delta;
392 		/* use loop to avoid checks for delta overflows */
393 		/* the delta value is small or zero in most cases */
394 		while (delta > 0) {
395 			new_hw_ptr += runtime->period_size;
396 			if (new_hw_ptr >= runtime->boundary) {
397 				new_hw_ptr -= runtime->boundary;
398 				crossed_boundary--;
399 			}
400 			delta--;
401 		}
402 		/* align hw_base to buffer_size */
403 		hw_ptr_error(substream, in_interrupt, "hw_ptr skipping",
404 			     "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
405 			     (long)pos, (long)hdelta,
406 			     (long)runtime->period_size, jdelta,
407 			     ((hdelta * HZ) / runtime->rate), hw_base,
408 			     (unsigned long)old_hw_ptr,
409 			     (unsigned long)new_hw_ptr);
410 		/* reset values to proper state */
411 		delta = 0;
412 		hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
413 	}
414  no_jiffies_check:
415 	if (delta > runtime->period_size + runtime->period_size / 2) {
416 		hw_ptr_error(substream, in_interrupt,
417 			     "Lost interrupts?",
418 			     "(stream=%i, delta=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
419 			     substream->stream, (long)delta,
420 			     (long)new_hw_ptr,
421 			     (long)old_hw_ptr);
422 	}
423 
424  no_delta_check:
425 	if (runtime->status->hw_ptr == new_hw_ptr) {
426 		update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
427 		return 0;
428 	}
429 
430 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
431 	    runtime->silence_size > 0)
432 		snd_pcm_playback_silence(substream, new_hw_ptr);
433 
434 	if (in_interrupt) {
435 		delta = new_hw_ptr - runtime->hw_ptr_interrupt;
436 		if (delta < 0)
437 			delta += runtime->boundary;
438 		delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
439 		runtime->hw_ptr_interrupt += delta;
440 		if (runtime->hw_ptr_interrupt >= runtime->boundary)
441 			runtime->hw_ptr_interrupt -= runtime->boundary;
442 	}
443 	runtime->hw_ptr_base = hw_base;
444 	runtime->status->hw_ptr = new_hw_ptr;
445 	runtime->hw_ptr_jiffies = curr_jiffies;
446 	if (crossed_boundary) {
447 		snd_BUG_ON(crossed_boundary != 1);
448 		runtime->hw_ptr_wrap += runtime->boundary;
449 	}
450 
451 	update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
452 
453 	return snd_pcm_update_state(substream, runtime);
454 }
455 
456 /* CAUTION: call it with irq disabled */
snd_pcm_update_hw_ptr(struct snd_pcm_substream * substream)457 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
458 {
459 	return snd_pcm_update_hw_ptr0(substream, 0);
460 }
461 
462 /**
463  * snd_pcm_set_ops - set the PCM operators
464  * @pcm: the pcm instance
465  * @direction: stream direction, SNDRV_PCM_STREAM_XXX
466  * @ops: the operator table
467  *
468  * Sets the given PCM operators to the pcm instance.
469  */
snd_pcm_set_ops(struct snd_pcm * pcm,int direction,const struct snd_pcm_ops * ops)470 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
471 		     const struct snd_pcm_ops *ops)
472 {
473 	struct snd_pcm_str *stream = &pcm->streams[direction];
474 	struct snd_pcm_substream *substream;
475 
476 	for (substream = stream->substream; substream != NULL; substream = substream->next)
477 		substream->ops = ops;
478 }
479 EXPORT_SYMBOL(snd_pcm_set_ops);
480 
481 /**
482  * snd_pcm_sync - set the PCM sync id
483  * @substream: the pcm substream
484  *
485  * Sets the PCM sync identifier for the card.
486  */
snd_pcm_set_sync(struct snd_pcm_substream * substream)487 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
488 {
489 	struct snd_pcm_runtime *runtime = substream->runtime;
490 
491 	runtime->sync.id32[0] = substream->pcm->card->number;
492 	runtime->sync.id32[1] = -1;
493 	runtime->sync.id32[2] = -1;
494 	runtime->sync.id32[3] = -1;
495 }
496 EXPORT_SYMBOL(snd_pcm_set_sync);
497 
498 /*
499  *  Standard ioctl routine
500  */
501 
div32(unsigned int a,unsigned int b,unsigned int * r)502 static inline unsigned int div32(unsigned int a, unsigned int b,
503 				 unsigned int *r)
504 {
505 	if (b == 0) {
506 		*r = 0;
507 		return UINT_MAX;
508 	}
509 	*r = a % b;
510 	return a / b;
511 }
512 
div_down(unsigned int a,unsigned int b)513 static inline unsigned int div_down(unsigned int a, unsigned int b)
514 {
515 	if (b == 0)
516 		return UINT_MAX;
517 	return a / b;
518 }
519 
div_up(unsigned int a,unsigned int b)520 static inline unsigned int div_up(unsigned int a, unsigned int b)
521 {
522 	unsigned int r;
523 	unsigned int q;
524 	if (b == 0)
525 		return UINT_MAX;
526 	q = div32(a, b, &r);
527 	if (r)
528 		++q;
529 	return q;
530 }
531 
mul(unsigned int a,unsigned int b)532 static inline unsigned int mul(unsigned int a, unsigned int b)
533 {
534 	if (a == 0)
535 		return 0;
536 	if (div_down(UINT_MAX, a) < b)
537 		return UINT_MAX;
538 	return a * b;
539 }
540 
muldiv32(unsigned int a,unsigned int b,unsigned int c,unsigned int * r)541 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
542 				    unsigned int c, unsigned int *r)
543 {
544 	u_int64_t n = (u_int64_t) a * b;
545 	if (c == 0) {
546 		*r = 0;
547 		return UINT_MAX;
548 	}
549 	n = div_u64_rem(n, c, r);
550 	if (n >= UINT_MAX) {
551 		*r = 0;
552 		return UINT_MAX;
553 	}
554 	return n;
555 }
556 
557 /**
558  * snd_interval_refine - refine the interval value of configurator
559  * @i: the interval value to refine
560  * @v: the interval value to refer to
561  *
562  * Refines the interval value with the reference value.
563  * The interval is changed to the range satisfying both intervals.
564  * The interval status (min, max, integer, etc.) are evaluated.
565  *
566  * Return: Positive if the value is changed, zero if it's not changed, or a
567  * negative error code.
568  */
snd_interval_refine(struct snd_interval * i,const struct snd_interval * v)569 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
570 {
571 	int changed = 0;
572 	if (snd_BUG_ON(snd_interval_empty(i)))
573 		return -EINVAL;
574 	if (i->min < v->min) {
575 		i->min = v->min;
576 		i->openmin = v->openmin;
577 		changed = 1;
578 	} else if (i->min == v->min && !i->openmin && v->openmin) {
579 		i->openmin = 1;
580 		changed = 1;
581 	}
582 	if (i->max > v->max) {
583 		i->max = v->max;
584 		i->openmax = v->openmax;
585 		changed = 1;
586 	} else if (i->max == v->max && !i->openmax && v->openmax) {
587 		i->openmax = 1;
588 		changed = 1;
589 	}
590 	if (!i->integer && v->integer) {
591 		i->integer = 1;
592 		changed = 1;
593 	}
594 	if (i->integer) {
595 		if (i->openmin) {
596 			i->min++;
597 			i->openmin = 0;
598 		}
599 		if (i->openmax) {
600 			i->max--;
601 			i->openmax = 0;
602 		}
603 	} else if (!i->openmin && !i->openmax && i->min == i->max)
604 		i->integer = 1;
605 	if (snd_interval_checkempty(i)) {
606 		snd_interval_none(i);
607 		return -EINVAL;
608 	}
609 	return changed;
610 }
611 EXPORT_SYMBOL(snd_interval_refine);
612 
snd_interval_refine_first(struct snd_interval * i)613 static int snd_interval_refine_first(struct snd_interval *i)
614 {
615 	const unsigned int last_max = i->max;
616 
617 	if (snd_BUG_ON(snd_interval_empty(i)))
618 		return -EINVAL;
619 	if (snd_interval_single(i))
620 		return 0;
621 	i->max = i->min;
622 	if (i->openmin)
623 		i->max++;
624 	/* only exclude max value if also excluded before refine */
625 	i->openmax = (i->openmax && i->max >= last_max);
626 	return 1;
627 }
628 
snd_interval_refine_last(struct snd_interval * i)629 static int snd_interval_refine_last(struct snd_interval *i)
630 {
631 	const unsigned int last_min = i->min;
632 
633 	if (snd_BUG_ON(snd_interval_empty(i)))
634 		return -EINVAL;
635 	if (snd_interval_single(i))
636 		return 0;
637 	i->min = i->max;
638 	if (i->openmax)
639 		i->min--;
640 	/* only exclude min value if also excluded before refine */
641 	i->openmin = (i->openmin && i->min <= last_min);
642 	return 1;
643 }
644 
snd_interval_mul(const struct snd_interval * a,const struct snd_interval * b,struct snd_interval * c)645 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
646 {
647 	if (a->empty || b->empty) {
648 		snd_interval_none(c);
649 		return;
650 	}
651 	c->empty = 0;
652 	c->min = mul(a->min, b->min);
653 	c->openmin = (a->openmin || b->openmin);
654 	c->max = mul(a->max,  b->max);
655 	c->openmax = (a->openmax || b->openmax);
656 	c->integer = (a->integer && b->integer);
657 }
658 
659 /**
660  * snd_interval_div - refine the interval value with division
661  * @a: dividend
662  * @b: divisor
663  * @c: quotient
664  *
665  * c = a / b
666  *
667  * Returns non-zero if the value is changed, zero if not changed.
668  */
snd_interval_div(const struct snd_interval * a,const struct snd_interval * b,struct snd_interval * c)669 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
670 {
671 	unsigned int r;
672 	if (a->empty || b->empty) {
673 		snd_interval_none(c);
674 		return;
675 	}
676 	c->empty = 0;
677 	c->min = div32(a->min, b->max, &r);
678 	c->openmin = (r || a->openmin || b->openmax);
679 	if (b->min > 0) {
680 		c->max = div32(a->max, b->min, &r);
681 		if (r) {
682 			c->max++;
683 			c->openmax = 1;
684 		} else
685 			c->openmax = (a->openmax || b->openmin);
686 	} else {
687 		c->max = UINT_MAX;
688 		c->openmax = 0;
689 	}
690 	c->integer = 0;
691 }
692 
693 /**
694  * snd_interval_muldivk - refine the interval value
695  * @a: dividend 1
696  * @b: dividend 2
697  * @k: divisor (as integer)
698  * @c: result
699   *
700  * c = a * b / k
701  *
702  * Returns non-zero if the value is changed, zero if not changed.
703  */
snd_interval_muldivk(const struct snd_interval * a,const struct snd_interval * b,unsigned int k,struct snd_interval * c)704 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
705 		      unsigned int k, struct snd_interval *c)
706 {
707 	unsigned int r;
708 	if (a->empty || b->empty) {
709 		snd_interval_none(c);
710 		return;
711 	}
712 	c->empty = 0;
713 	c->min = muldiv32(a->min, b->min, k, &r);
714 	c->openmin = (r || a->openmin || b->openmin);
715 	c->max = muldiv32(a->max, b->max, k, &r);
716 	if (r) {
717 		c->max++;
718 		c->openmax = 1;
719 	} else
720 		c->openmax = (a->openmax || b->openmax);
721 	c->integer = 0;
722 }
723 
724 /**
725  * snd_interval_mulkdiv - refine the interval value
726  * @a: dividend 1
727  * @k: dividend 2 (as integer)
728  * @b: divisor
729  * @c: result
730  *
731  * c = a * k / b
732  *
733  * Returns non-zero if the value is changed, zero if not changed.
734  */
snd_interval_mulkdiv(const struct snd_interval * a,unsigned int k,const struct snd_interval * b,struct snd_interval * c)735 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
736 		      const struct snd_interval *b, struct snd_interval *c)
737 {
738 	unsigned int r;
739 	if (a->empty || b->empty) {
740 		snd_interval_none(c);
741 		return;
742 	}
743 	c->empty = 0;
744 	c->min = muldiv32(a->min, k, b->max, &r);
745 	c->openmin = (r || a->openmin || b->openmax);
746 	if (b->min > 0) {
747 		c->max = muldiv32(a->max, k, b->min, &r);
748 		if (r) {
749 			c->max++;
750 			c->openmax = 1;
751 		} else
752 			c->openmax = (a->openmax || b->openmin);
753 	} else {
754 		c->max = UINT_MAX;
755 		c->openmax = 0;
756 	}
757 	c->integer = 0;
758 }
759 
760 /* ---- */
761 
762 
763 /**
764  * snd_interval_ratnum - refine the interval value
765  * @i: interval to refine
766  * @rats_count: number of ratnum_t
767  * @rats: ratnum_t array
768  * @nump: pointer to store the resultant numerator
769  * @denp: pointer to store the resultant denominator
770  *
771  * Return: Positive if the value is changed, zero if it's not changed, or a
772  * negative error code.
773  */
snd_interval_ratnum(struct snd_interval * i,unsigned int rats_count,const struct snd_ratnum * rats,unsigned int * nump,unsigned int * denp)774 int snd_interval_ratnum(struct snd_interval *i,
775 			unsigned int rats_count, const struct snd_ratnum *rats,
776 			unsigned int *nump, unsigned int *denp)
777 {
778 	unsigned int best_num, best_den;
779 	int best_diff;
780 	unsigned int k;
781 	struct snd_interval t;
782 	int err;
783 	unsigned int result_num, result_den;
784 	int result_diff;
785 
786 	best_num = best_den = best_diff = 0;
787 	for (k = 0; k < rats_count; ++k) {
788 		unsigned int num = rats[k].num;
789 		unsigned int den;
790 		unsigned int q = i->min;
791 		int diff;
792 		if (q == 0)
793 			q = 1;
794 		den = div_up(num, q);
795 		if (den < rats[k].den_min)
796 			continue;
797 		if (den > rats[k].den_max)
798 			den = rats[k].den_max;
799 		else {
800 			unsigned int r;
801 			r = (den - rats[k].den_min) % rats[k].den_step;
802 			if (r != 0)
803 				den -= r;
804 		}
805 		diff = num - q * den;
806 		if (diff < 0)
807 			diff = -diff;
808 		if (best_num == 0 ||
809 		    diff * best_den < best_diff * den) {
810 			best_diff = diff;
811 			best_den = den;
812 			best_num = num;
813 		}
814 	}
815 	if (best_den == 0) {
816 		i->empty = 1;
817 		return -EINVAL;
818 	}
819 	t.min = div_down(best_num, best_den);
820 	t.openmin = !!(best_num % best_den);
821 
822 	result_num = best_num;
823 	result_diff = best_diff;
824 	result_den = best_den;
825 	best_num = best_den = best_diff = 0;
826 	for (k = 0; k < rats_count; ++k) {
827 		unsigned int num = rats[k].num;
828 		unsigned int den;
829 		unsigned int q = i->max;
830 		int diff;
831 		if (q == 0) {
832 			i->empty = 1;
833 			return -EINVAL;
834 		}
835 		den = div_down(num, q);
836 		if (den > rats[k].den_max)
837 			continue;
838 		if (den < rats[k].den_min)
839 			den = rats[k].den_min;
840 		else {
841 			unsigned int r;
842 			r = (den - rats[k].den_min) % rats[k].den_step;
843 			if (r != 0)
844 				den += rats[k].den_step - r;
845 		}
846 		diff = q * den - num;
847 		if (diff < 0)
848 			diff = -diff;
849 		if (best_num == 0 ||
850 		    diff * best_den < best_diff * den) {
851 			best_diff = diff;
852 			best_den = den;
853 			best_num = num;
854 		}
855 	}
856 	if (best_den == 0) {
857 		i->empty = 1;
858 		return -EINVAL;
859 	}
860 	t.max = div_up(best_num, best_den);
861 	t.openmax = !!(best_num % best_den);
862 	t.integer = 0;
863 	err = snd_interval_refine(i, &t);
864 	if (err < 0)
865 		return err;
866 
867 	if (snd_interval_single(i)) {
868 		if (best_diff * result_den < result_diff * best_den) {
869 			result_num = best_num;
870 			result_den = best_den;
871 		}
872 		if (nump)
873 			*nump = result_num;
874 		if (denp)
875 			*denp = result_den;
876 	}
877 	return err;
878 }
879 EXPORT_SYMBOL(snd_interval_ratnum);
880 
881 /**
882  * snd_interval_ratden - refine the interval value
883  * @i: interval to refine
884  * @rats_count: number of struct ratden
885  * @rats: struct ratden array
886  * @nump: pointer to store the resultant numerator
887  * @denp: pointer to store the resultant denominator
888  *
889  * Return: Positive if the value is changed, zero if it's not changed, or a
890  * negative error code.
891  */
snd_interval_ratden(struct snd_interval * i,unsigned int rats_count,const struct snd_ratden * rats,unsigned int * nump,unsigned int * denp)892 static int snd_interval_ratden(struct snd_interval *i,
893 			       unsigned int rats_count,
894 			       const struct snd_ratden *rats,
895 			       unsigned int *nump, unsigned int *denp)
896 {
897 	unsigned int best_num, best_diff, best_den;
898 	unsigned int k;
899 	struct snd_interval t;
900 	int err;
901 
902 	best_num = best_den = best_diff = 0;
903 	for (k = 0; k < rats_count; ++k) {
904 		unsigned int num;
905 		unsigned int den = rats[k].den;
906 		unsigned int q = i->min;
907 		int diff;
908 		num = mul(q, den);
909 		if (num > rats[k].num_max)
910 			continue;
911 		if (num < rats[k].num_min)
912 			num = rats[k].num_max;
913 		else {
914 			unsigned int r;
915 			r = (num - rats[k].num_min) % rats[k].num_step;
916 			if (r != 0)
917 				num += rats[k].num_step - r;
918 		}
919 		diff = num - q * den;
920 		if (best_num == 0 ||
921 		    diff * best_den < best_diff * den) {
922 			best_diff = diff;
923 			best_den = den;
924 			best_num = num;
925 		}
926 	}
927 	if (best_den == 0) {
928 		i->empty = 1;
929 		return -EINVAL;
930 	}
931 	t.min = div_down(best_num, best_den);
932 	t.openmin = !!(best_num % best_den);
933 
934 	best_num = best_den = best_diff = 0;
935 	for (k = 0; k < rats_count; ++k) {
936 		unsigned int num;
937 		unsigned int den = rats[k].den;
938 		unsigned int q = i->max;
939 		int diff;
940 		num = mul(q, den);
941 		if (num < rats[k].num_min)
942 			continue;
943 		if (num > rats[k].num_max)
944 			num = rats[k].num_max;
945 		else {
946 			unsigned int r;
947 			r = (num - rats[k].num_min) % rats[k].num_step;
948 			if (r != 0)
949 				num -= r;
950 		}
951 		diff = q * den - num;
952 		if (best_num == 0 ||
953 		    diff * best_den < best_diff * den) {
954 			best_diff = diff;
955 			best_den = den;
956 			best_num = num;
957 		}
958 	}
959 	if (best_den == 0) {
960 		i->empty = 1;
961 		return -EINVAL;
962 	}
963 	t.max = div_up(best_num, best_den);
964 	t.openmax = !!(best_num % best_den);
965 	t.integer = 0;
966 	err = snd_interval_refine(i, &t);
967 	if (err < 0)
968 		return err;
969 
970 	if (snd_interval_single(i)) {
971 		if (nump)
972 			*nump = best_num;
973 		if (denp)
974 			*denp = best_den;
975 	}
976 	return err;
977 }
978 
979 /**
980  * snd_interval_list - refine the interval value from the list
981  * @i: the interval value to refine
982  * @count: the number of elements in the list
983  * @list: the value list
984  * @mask: the bit-mask to evaluate
985  *
986  * Refines the interval value from the list.
987  * When mask is non-zero, only the elements corresponding to bit 1 are
988  * evaluated.
989  *
990  * Return: Positive if the value is changed, zero if it's not changed, or a
991  * negative error code.
992  */
snd_interval_list(struct snd_interval * i,unsigned int count,const unsigned int * list,unsigned int mask)993 int snd_interval_list(struct snd_interval *i, unsigned int count,
994 		      const unsigned int *list, unsigned int mask)
995 {
996         unsigned int k;
997 	struct snd_interval list_range;
998 
999 	if (!count) {
1000 		i->empty = 1;
1001 		return -EINVAL;
1002 	}
1003 	snd_interval_any(&list_range);
1004 	list_range.min = UINT_MAX;
1005 	list_range.max = 0;
1006         for (k = 0; k < count; k++) {
1007 		if (mask && !(mask & (1 << k)))
1008 			continue;
1009 		if (!snd_interval_test(i, list[k]))
1010 			continue;
1011 		list_range.min = min(list_range.min, list[k]);
1012 		list_range.max = max(list_range.max, list[k]);
1013         }
1014 	return snd_interval_refine(i, &list_range);
1015 }
1016 EXPORT_SYMBOL(snd_interval_list);
1017 
1018 /**
1019  * snd_interval_ranges - refine the interval value from the list of ranges
1020  * @i: the interval value to refine
1021  * @count: the number of elements in the list of ranges
1022  * @ranges: the ranges list
1023  * @mask: the bit-mask to evaluate
1024  *
1025  * Refines the interval value from the list of ranges.
1026  * When mask is non-zero, only the elements corresponding to bit 1 are
1027  * evaluated.
1028  *
1029  * Return: Positive if the value is changed, zero if it's not changed, or a
1030  * negative error code.
1031  */
snd_interval_ranges(struct snd_interval * i,unsigned int count,const struct snd_interval * ranges,unsigned int mask)1032 int snd_interval_ranges(struct snd_interval *i, unsigned int count,
1033 			const struct snd_interval *ranges, unsigned int mask)
1034 {
1035 	unsigned int k;
1036 	struct snd_interval range_union;
1037 	struct snd_interval range;
1038 
1039 	if (!count) {
1040 		snd_interval_none(i);
1041 		return -EINVAL;
1042 	}
1043 	snd_interval_any(&range_union);
1044 	range_union.min = UINT_MAX;
1045 	range_union.max = 0;
1046 	for (k = 0; k < count; k++) {
1047 		if (mask && !(mask & (1 << k)))
1048 			continue;
1049 		snd_interval_copy(&range, &ranges[k]);
1050 		if (snd_interval_refine(&range, i) < 0)
1051 			continue;
1052 		if (snd_interval_empty(&range))
1053 			continue;
1054 
1055 		if (range.min < range_union.min) {
1056 			range_union.min = range.min;
1057 			range_union.openmin = 1;
1058 		}
1059 		if (range.min == range_union.min && !range.openmin)
1060 			range_union.openmin = 0;
1061 		if (range.max > range_union.max) {
1062 			range_union.max = range.max;
1063 			range_union.openmax = 1;
1064 		}
1065 		if (range.max == range_union.max && !range.openmax)
1066 			range_union.openmax = 0;
1067 	}
1068 	return snd_interval_refine(i, &range_union);
1069 }
1070 EXPORT_SYMBOL(snd_interval_ranges);
1071 
snd_interval_step(struct snd_interval * i,unsigned int step)1072 static int snd_interval_step(struct snd_interval *i, unsigned int step)
1073 {
1074 	unsigned int n;
1075 	int changed = 0;
1076 	n = i->min % step;
1077 	if (n != 0 || i->openmin) {
1078 		i->min += step - n;
1079 		i->openmin = 0;
1080 		changed = 1;
1081 	}
1082 	n = i->max % step;
1083 	if (n != 0 || i->openmax) {
1084 		i->max -= n;
1085 		i->openmax = 0;
1086 		changed = 1;
1087 	}
1088 	if (snd_interval_checkempty(i)) {
1089 		i->empty = 1;
1090 		return -EINVAL;
1091 	}
1092 	return changed;
1093 }
1094 
1095 /* Info constraints helpers */
1096 
1097 /**
1098  * snd_pcm_hw_rule_add - add the hw-constraint rule
1099  * @runtime: the pcm runtime instance
1100  * @cond: condition bits
1101  * @var: the variable to evaluate
1102  * @func: the evaluation function
1103  * @private: the private data pointer passed to function
1104  * @dep: the dependent variables
1105  *
1106  * Return: Zero if successful, or a negative error code on failure.
1107  */
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,...)1108 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1109 			int var,
1110 			snd_pcm_hw_rule_func_t func, void *private,
1111 			int dep, ...)
1112 {
1113 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1114 	struct snd_pcm_hw_rule *c;
1115 	unsigned int k;
1116 	va_list args;
1117 	va_start(args, dep);
1118 	if (constrs->rules_num >= constrs->rules_all) {
1119 		struct snd_pcm_hw_rule *new;
1120 		unsigned int new_rules = constrs->rules_all + 16;
1121 		new = krealloc(constrs->rules, new_rules * sizeof(*c),
1122 			       GFP_KERNEL);
1123 		if (!new) {
1124 			va_end(args);
1125 			return -ENOMEM;
1126 		}
1127 		constrs->rules = new;
1128 		constrs->rules_all = new_rules;
1129 	}
1130 	c = &constrs->rules[constrs->rules_num];
1131 	c->cond = cond;
1132 	c->func = func;
1133 	c->var = var;
1134 	c->private = private;
1135 	k = 0;
1136 	while (1) {
1137 		if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1138 			va_end(args);
1139 			return -EINVAL;
1140 		}
1141 		c->deps[k++] = dep;
1142 		if (dep < 0)
1143 			break;
1144 		dep = va_arg(args, int);
1145 	}
1146 	constrs->rules_num++;
1147 	va_end(args);
1148 	return 0;
1149 }
1150 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1151 
1152 /**
1153  * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1154  * @runtime: PCM runtime instance
1155  * @var: hw_params variable to apply the mask
1156  * @mask: the bitmap mask
1157  *
1158  * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1159  *
1160  * Return: Zero if successful, or a negative error code on failure.
1161  */
snd_pcm_hw_constraint_mask(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var,u_int32_t mask)1162 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1163 			       u_int32_t mask)
1164 {
1165 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1166 	struct snd_mask *maskp = constrs_mask(constrs, var);
1167 	*maskp->bits &= mask;
1168 	memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1169 	if (*maskp->bits == 0)
1170 		return -EINVAL;
1171 	return 0;
1172 }
1173 
1174 /**
1175  * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1176  * @runtime: PCM runtime instance
1177  * @var: hw_params variable to apply the mask
1178  * @mask: the 64bit bitmap mask
1179  *
1180  * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1181  *
1182  * Return: Zero if successful, or a negative error code on failure.
1183  */
snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var,u_int64_t mask)1184 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1185 				 u_int64_t mask)
1186 {
1187 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1188 	struct snd_mask *maskp = constrs_mask(constrs, var);
1189 	maskp->bits[0] &= (u_int32_t)mask;
1190 	maskp->bits[1] &= (u_int32_t)(mask >> 32);
1191 	memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1192 	if (! maskp->bits[0] && ! maskp->bits[1])
1193 		return -EINVAL;
1194 	return 0;
1195 }
1196 EXPORT_SYMBOL(snd_pcm_hw_constraint_mask64);
1197 
1198 /**
1199  * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1200  * @runtime: PCM runtime instance
1201  * @var: hw_params variable to apply the integer constraint
1202  *
1203  * Apply the constraint of integer to an interval parameter.
1204  *
1205  * Return: Positive if the value is changed, zero if it's not changed, or a
1206  * negative error code.
1207  */
snd_pcm_hw_constraint_integer(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var)1208 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1209 {
1210 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1211 	return snd_interval_setinteger(constrs_interval(constrs, var));
1212 }
1213 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1214 
1215 /**
1216  * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1217  * @runtime: PCM runtime instance
1218  * @var: hw_params variable to apply the range
1219  * @min: the minimal value
1220  * @max: the maximal value
1221  *
1222  * Apply the min/max range constraint to an interval parameter.
1223  *
1224  * Return: Positive if the value is changed, zero if it's not changed, or a
1225  * negative error code.
1226  */
snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime * runtime,snd_pcm_hw_param_t var,unsigned int min,unsigned int max)1227 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1228 				 unsigned int min, unsigned int max)
1229 {
1230 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1231 	struct snd_interval t;
1232 	t.min = min;
1233 	t.max = max;
1234 	t.openmin = t.openmax = 0;
1235 	t.integer = 0;
1236 	return snd_interval_refine(constrs_interval(constrs, var), &t);
1237 }
1238 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1239 
snd_pcm_hw_rule_list(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1240 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1241 				struct snd_pcm_hw_rule *rule)
1242 {
1243 	struct snd_pcm_hw_constraint_list *list = rule->private;
1244 	return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1245 }
1246 
1247 
1248 /**
1249  * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1250  * @runtime: PCM runtime instance
1251  * @cond: condition bits
1252  * @var: hw_params variable to apply the list constraint
1253  * @l: list
1254  *
1255  * Apply the list of constraints to an interval parameter.
1256  *
1257  * Return: Zero if successful, or a negative error code on failure.
1258  */
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)1259 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1260 			       unsigned int cond,
1261 			       snd_pcm_hw_param_t var,
1262 			       const struct snd_pcm_hw_constraint_list *l)
1263 {
1264 	return snd_pcm_hw_rule_add(runtime, cond, var,
1265 				   snd_pcm_hw_rule_list, (void *)l,
1266 				   var, -1);
1267 }
1268 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1269 
snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1270 static int snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params *params,
1271 				  struct snd_pcm_hw_rule *rule)
1272 {
1273 	struct snd_pcm_hw_constraint_ranges *r = rule->private;
1274 	return snd_interval_ranges(hw_param_interval(params, rule->var),
1275 				   r->count, r->ranges, r->mask);
1276 }
1277 
1278 
1279 /**
1280  * snd_pcm_hw_constraint_ranges - apply list of range constraints to a parameter
1281  * @runtime: PCM runtime instance
1282  * @cond: condition bits
1283  * @var: hw_params variable to apply the list of range constraints
1284  * @r: ranges
1285  *
1286  * Apply the list of range constraints to an interval parameter.
1287  *
1288  * Return: Zero if successful, or a negative error code on failure.
1289  */
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)1290 int snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime *runtime,
1291 				 unsigned int cond,
1292 				 snd_pcm_hw_param_t var,
1293 				 const struct snd_pcm_hw_constraint_ranges *r)
1294 {
1295 	return snd_pcm_hw_rule_add(runtime, cond, var,
1296 				   snd_pcm_hw_rule_ranges, (void *)r,
1297 				   var, -1);
1298 }
1299 EXPORT_SYMBOL(snd_pcm_hw_constraint_ranges);
1300 
snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1301 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1302 				   struct snd_pcm_hw_rule *rule)
1303 {
1304 	const struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1305 	unsigned int num = 0, den = 0;
1306 	int err;
1307 	err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1308 				  r->nrats, r->rats, &num, &den);
1309 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1310 		params->rate_num = num;
1311 		params->rate_den = den;
1312 	}
1313 	return err;
1314 }
1315 
1316 /**
1317  * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1318  * @runtime: PCM runtime instance
1319  * @cond: condition bits
1320  * @var: hw_params variable to apply the ratnums constraint
1321  * @r: struct snd_ratnums constriants
1322  *
1323  * Return: Zero if successful, or a negative error code on failure.
1324  */
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)1325 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1326 				  unsigned int cond,
1327 				  snd_pcm_hw_param_t var,
1328 				  const struct snd_pcm_hw_constraint_ratnums *r)
1329 {
1330 	return snd_pcm_hw_rule_add(runtime, cond, var,
1331 				   snd_pcm_hw_rule_ratnums, (void *)r,
1332 				   var, -1);
1333 }
1334 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1335 
snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1336 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1337 				   struct snd_pcm_hw_rule *rule)
1338 {
1339 	const struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1340 	unsigned int num = 0, den = 0;
1341 	int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1342 				  r->nrats, r->rats, &num, &den);
1343 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1344 		params->rate_num = num;
1345 		params->rate_den = den;
1346 	}
1347 	return err;
1348 }
1349 
1350 /**
1351  * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1352  * @runtime: PCM runtime instance
1353  * @cond: condition bits
1354  * @var: hw_params variable to apply the ratdens constraint
1355  * @r: struct snd_ratdens constriants
1356  *
1357  * Return: Zero if successful, or a negative error code on failure.
1358  */
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)1359 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1360 				  unsigned int cond,
1361 				  snd_pcm_hw_param_t var,
1362 				  const struct snd_pcm_hw_constraint_ratdens *r)
1363 {
1364 	return snd_pcm_hw_rule_add(runtime, cond, var,
1365 				   snd_pcm_hw_rule_ratdens, (void *)r,
1366 				   var, -1);
1367 }
1368 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1369 
snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1370 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1371 				  struct snd_pcm_hw_rule *rule)
1372 {
1373 	unsigned int l = (unsigned long) rule->private;
1374 	int width = l & 0xffff;
1375 	unsigned int msbits = l >> 16;
1376 	const struct snd_interval *i =
1377 		hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1378 
1379 	if (!snd_interval_single(i))
1380 		return 0;
1381 
1382 	if ((snd_interval_value(i) == width) ||
1383 	    (width == 0 && snd_interval_value(i) > msbits))
1384 		params->msbits = min_not_zero(params->msbits, msbits);
1385 
1386 	return 0;
1387 }
1388 
1389 /**
1390  * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1391  * @runtime: PCM runtime instance
1392  * @cond: condition bits
1393  * @width: sample bits width
1394  * @msbits: msbits width
1395  *
1396  * This constraint will set the number of most significant bits (msbits) if a
1397  * sample format with the specified width has been select. If width is set to 0
1398  * the msbits will be set for any sample format with a width larger than the
1399  * specified msbits.
1400  *
1401  * Return: Zero if successful, or a negative error code on failure.
1402  */
snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime * runtime,unsigned int cond,unsigned int width,unsigned int msbits)1403 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1404 				 unsigned int cond,
1405 				 unsigned int width,
1406 				 unsigned int msbits)
1407 {
1408 	unsigned long l = (msbits << 16) | width;
1409 	return snd_pcm_hw_rule_add(runtime, cond, -1,
1410 				    snd_pcm_hw_rule_msbits,
1411 				    (void*) l,
1412 				    SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1413 }
1414 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1415 
snd_pcm_hw_rule_step(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1416 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1417 				struct snd_pcm_hw_rule *rule)
1418 {
1419 	unsigned long step = (unsigned long) rule->private;
1420 	return snd_interval_step(hw_param_interval(params, rule->var), step);
1421 }
1422 
1423 /**
1424  * snd_pcm_hw_constraint_step - add a hw constraint step rule
1425  * @runtime: PCM runtime instance
1426  * @cond: condition bits
1427  * @var: hw_params variable to apply the step constraint
1428  * @step: step size
1429  *
1430  * Return: Zero if successful, or a negative error code on failure.
1431  */
snd_pcm_hw_constraint_step(struct snd_pcm_runtime * runtime,unsigned int cond,snd_pcm_hw_param_t var,unsigned long step)1432 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1433 			       unsigned int cond,
1434 			       snd_pcm_hw_param_t var,
1435 			       unsigned long step)
1436 {
1437 	return snd_pcm_hw_rule_add(runtime, cond, var,
1438 				   snd_pcm_hw_rule_step, (void *) step,
1439 				   var, -1);
1440 }
1441 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1442 
snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1443 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1444 {
1445 	static unsigned int pow2_sizes[] = {
1446 		1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1447 		1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1448 		1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1449 		1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1450 	};
1451 	return snd_interval_list(hw_param_interval(params, rule->var),
1452 				 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1453 }
1454 
1455 /**
1456  * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1457  * @runtime: PCM runtime instance
1458  * @cond: condition bits
1459  * @var: hw_params variable to apply the power-of-2 constraint
1460  *
1461  * Return: Zero if successful, or a negative error code on failure.
1462  */
snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime * runtime,unsigned int cond,snd_pcm_hw_param_t var)1463 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1464 			       unsigned int cond,
1465 			       snd_pcm_hw_param_t var)
1466 {
1467 	return snd_pcm_hw_rule_add(runtime, cond, var,
1468 				   snd_pcm_hw_rule_pow2, NULL,
1469 				   var, -1);
1470 }
1471 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1472 
snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)1473 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1474 					   struct snd_pcm_hw_rule *rule)
1475 {
1476 	unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1477 	struct snd_interval *rate;
1478 
1479 	rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1480 	return snd_interval_list(rate, 1, &base_rate, 0);
1481 }
1482 
1483 /**
1484  * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1485  * @runtime: PCM runtime instance
1486  * @base_rate: the rate at which the hardware does not resample
1487  *
1488  * Return: Zero if successful, or a negative error code on failure.
1489  */
snd_pcm_hw_rule_noresample(struct snd_pcm_runtime * runtime,unsigned int base_rate)1490 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1491 			       unsigned int base_rate)
1492 {
1493 	return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1494 				   SNDRV_PCM_HW_PARAM_RATE,
1495 				   snd_pcm_hw_rule_noresample_func,
1496 				   (void *)(uintptr_t)base_rate,
1497 				   SNDRV_PCM_HW_PARAM_RATE, -1);
1498 }
1499 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1500 
_snd_pcm_hw_param_any(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1501 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1502 				  snd_pcm_hw_param_t var)
1503 {
1504 	if (hw_is_mask(var)) {
1505 		snd_mask_any(hw_param_mask(params, var));
1506 		params->cmask |= 1 << var;
1507 		params->rmask |= 1 << var;
1508 		return;
1509 	}
1510 	if (hw_is_interval(var)) {
1511 		snd_interval_any(hw_param_interval(params, var));
1512 		params->cmask |= 1 << var;
1513 		params->rmask |= 1 << var;
1514 		return;
1515 	}
1516 	snd_BUG();
1517 }
1518 
_snd_pcm_hw_params_any(struct snd_pcm_hw_params * params)1519 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1520 {
1521 	unsigned int k;
1522 	memset(params, 0, sizeof(*params));
1523 	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1524 		_snd_pcm_hw_param_any(params, k);
1525 	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1526 		_snd_pcm_hw_param_any(params, k);
1527 	params->info = ~0U;
1528 }
1529 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1530 
1531 /**
1532  * snd_pcm_hw_param_value - return @params field @var value
1533  * @params: the hw_params instance
1534  * @var: parameter to retrieve
1535  * @dir: pointer to the direction (-1,0,1) or %NULL
1536  *
1537  * Return: The value for field @var if it's fixed in configuration space
1538  * defined by @params. -%EINVAL otherwise.
1539  */
snd_pcm_hw_param_value(const struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var,int * dir)1540 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1541 			   snd_pcm_hw_param_t var, int *dir)
1542 {
1543 	if (hw_is_mask(var)) {
1544 		const struct snd_mask *mask = hw_param_mask_c(params, var);
1545 		if (!snd_mask_single(mask))
1546 			return -EINVAL;
1547 		if (dir)
1548 			*dir = 0;
1549 		return snd_mask_value(mask);
1550 	}
1551 	if (hw_is_interval(var)) {
1552 		const struct snd_interval *i = hw_param_interval_c(params, var);
1553 		if (!snd_interval_single(i))
1554 			return -EINVAL;
1555 		if (dir)
1556 			*dir = i->openmin;
1557 		return snd_interval_value(i);
1558 	}
1559 	return -EINVAL;
1560 }
1561 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1562 
_snd_pcm_hw_param_setempty(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1563 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1564 				snd_pcm_hw_param_t var)
1565 {
1566 	if (hw_is_mask(var)) {
1567 		snd_mask_none(hw_param_mask(params, var));
1568 		params->cmask |= 1 << var;
1569 		params->rmask |= 1 << var;
1570 	} else if (hw_is_interval(var)) {
1571 		snd_interval_none(hw_param_interval(params, var));
1572 		params->cmask |= 1 << var;
1573 		params->rmask |= 1 << var;
1574 	} else {
1575 		snd_BUG();
1576 	}
1577 }
1578 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1579 
_snd_pcm_hw_param_first(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1580 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1581 				   snd_pcm_hw_param_t var)
1582 {
1583 	int changed;
1584 	if (hw_is_mask(var))
1585 		changed = snd_mask_refine_first(hw_param_mask(params, var));
1586 	else if (hw_is_interval(var))
1587 		changed = snd_interval_refine_first(hw_param_interval(params, var));
1588 	else
1589 		return -EINVAL;
1590 	if (changed > 0) {
1591 		params->cmask |= 1 << var;
1592 		params->rmask |= 1 << var;
1593 	}
1594 	return changed;
1595 }
1596 
1597 
1598 /**
1599  * snd_pcm_hw_param_first - refine config space and return minimum value
1600  * @pcm: PCM instance
1601  * @params: the hw_params instance
1602  * @var: parameter to retrieve
1603  * @dir: pointer to the direction (-1,0,1) or %NULL
1604  *
1605  * Inside configuration space defined by @params remove from @var all
1606  * values > minimum. Reduce configuration space accordingly.
1607  *
1608  * Return: The minimum, or a negative error code on failure.
1609  */
snd_pcm_hw_param_first(struct snd_pcm_substream * pcm,struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var,int * dir)1610 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1611 			   struct snd_pcm_hw_params *params,
1612 			   snd_pcm_hw_param_t var, int *dir)
1613 {
1614 	int changed = _snd_pcm_hw_param_first(params, var);
1615 	if (changed < 0)
1616 		return changed;
1617 	if (params->rmask) {
1618 		int err = snd_pcm_hw_refine(pcm, params);
1619 		if (err < 0)
1620 			return err;
1621 	}
1622 	return snd_pcm_hw_param_value(params, var, dir);
1623 }
1624 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1625 
_snd_pcm_hw_param_last(struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var)1626 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1627 				  snd_pcm_hw_param_t var)
1628 {
1629 	int changed;
1630 	if (hw_is_mask(var))
1631 		changed = snd_mask_refine_last(hw_param_mask(params, var));
1632 	else if (hw_is_interval(var))
1633 		changed = snd_interval_refine_last(hw_param_interval(params, var));
1634 	else
1635 		return -EINVAL;
1636 	if (changed > 0) {
1637 		params->cmask |= 1 << var;
1638 		params->rmask |= 1 << var;
1639 	}
1640 	return changed;
1641 }
1642 
1643 
1644 /**
1645  * snd_pcm_hw_param_last - refine config space and return maximum value
1646  * @pcm: PCM instance
1647  * @params: the hw_params instance
1648  * @var: parameter to retrieve
1649  * @dir: pointer to the direction (-1,0,1) or %NULL
1650  *
1651  * Inside configuration space defined by @params remove from @var all
1652  * values < maximum. Reduce configuration space accordingly.
1653  *
1654  * Return: The maximum, or a negative error code on failure.
1655  */
snd_pcm_hw_param_last(struct snd_pcm_substream * pcm,struct snd_pcm_hw_params * params,snd_pcm_hw_param_t var,int * dir)1656 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1657 			  struct snd_pcm_hw_params *params,
1658 			  snd_pcm_hw_param_t var, int *dir)
1659 {
1660 	int changed = _snd_pcm_hw_param_last(params, var);
1661 	if (changed < 0)
1662 		return changed;
1663 	if (params->rmask) {
1664 		int err = snd_pcm_hw_refine(pcm, params);
1665 		if (err < 0)
1666 			return err;
1667 	}
1668 	return snd_pcm_hw_param_value(params, var, dir);
1669 }
1670 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1671 
snd_pcm_lib_ioctl_reset(struct snd_pcm_substream * substream,void * arg)1672 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1673 				   void *arg)
1674 {
1675 	struct snd_pcm_runtime *runtime = substream->runtime;
1676 	unsigned long flags;
1677 	snd_pcm_stream_lock_irqsave(substream, flags);
1678 	if (snd_pcm_running(substream) &&
1679 	    snd_pcm_update_hw_ptr(substream) >= 0)
1680 		runtime->status->hw_ptr %= runtime->buffer_size;
1681 	else {
1682 		runtime->status->hw_ptr = 0;
1683 		runtime->hw_ptr_wrap = 0;
1684 	}
1685 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1686 	return 0;
1687 }
1688 
snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream * substream,void * arg)1689 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1690 					  void *arg)
1691 {
1692 	struct snd_pcm_channel_info *info = arg;
1693 	struct snd_pcm_runtime *runtime = substream->runtime;
1694 	int width;
1695 	if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1696 		info->offset = -1;
1697 		return 0;
1698 	}
1699 	width = snd_pcm_format_physical_width(runtime->format);
1700 	if (width < 0)
1701 		return width;
1702 	info->offset = 0;
1703 	switch (runtime->access) {
1704 	case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1705 	case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1706 		info->first = info->channel * width;
1707 		info->step = runtime->channels * width;
1708 		break;
1709 	case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1710 	case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1711 	{
1712 		size_t size = runtime->dma_bytes / runtime->channels;
1713 		info->first = info->channel * size * 8;
1714 		info->step = width;
1715 		break;
1716 	}
1717 	default:
1718 		snd_BUG();
1719 		break;
1720 	}
1721 	return 0;
1722 }
1723 
snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream * substream,void * arg)1724 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1725 				       void *arg)
1726 {
1727 	struct snd_pcm_hw_params *params = arg;
1728 	snd_pcm_format_t format;
1729 	int channels;
1730 	ssize_t frame_size;
1731 
1732 	params->fifo_size = substream->runtime->hw.fifo_size;
1733 	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1734 		format = params_format(params);
1735 		channels = params_channels(params);
1736 		frame_size = snd_pcm_format_size(format, channels);
1737 		if (frame_size > 0)
1738 			params->fifo_size /= (unsigned)frame_size;
1739 	}
1740 	return 0;
1741 }
1742 
1743 /**
1744  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1745  * @substream: the pcm substream instance
1746  * @cmd: ioctl command
1747  * @arg: ioctl argument
1748  *
1749  * Processes the generic ioctl commands for PCM.
1750  * Can be passed as the ioctl callback for PCM ops.
1751  *
1752  * Return: Zero if successful, or a negative error code on failure.
1753  */
snd_pcm_lib_ioctl(struct snd_pcm_substream * substream,unsigned int cmd,void * arg)1754 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1755 		      unsigned int cmd, void *arg)
1756 {
1757 	switch (cmd) {
1758 	case SNDRV_PCM_IOCTL1_RESET:
1759 		return snd_pcm_lib_ioctl_reset(substream, arg);
1760 	case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1761 		return snd_pcm_lib_ioctl_channel_info(substream, arg);
1762 	case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1763 		return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1764 	}
1765 	return -ENXIO;
1766 }
1767 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1768 
1769 /**
1770  * snd_pcm_period_elapsed - update the pcm status for the next period
1771  * @substream: the pcm substream instance
1772  *
1773  * This function is called from the interrupt handler when the
1774  * PCM has processed the period size.  It will update the current
1775  * pointer, wake up sleepers, etc.
1776  *
1777  * Even if more than one periods have elapsed since the last call, you
1778  * have to call this only once.
1779  */
snd_pcm_period_elapsed(struct snd_pcm_substream * substream)1780 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1781 {
1782 	struct snd_pcm_runtime *runtime;
1783 	unsigned long flags;
1784 
1785 	if (snd_BUG_ON(!substream))
1786 		return;
1787 
1788 	snd_pcm_stream_lock_irqsave(substream, flags);
1789 	if (PCM_RUNTIME_CHECK(substream))
1790 		goto _unlock;
1791 	runtime = substream->runtime;
1792 
1793 	if (!snd_pcm_running(substream) ||
1794 	    snd_pcm_update_hw_ptr0(substream, 1) < 0)
1795 		goto _end;
1796 
1797 #ifdef CONFIG_SND_PCM_TIMER
1798 	if (substream->timer_running)
1799 		snd_timer_interrupt(substream->timer, 1);
1800 #endif
1801  _end:
1802 	kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1803  _unlock:
1804 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1805 }
1806 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1807 
1808 /*
1809  * Wait until avail_min data becomes available
1810  * Returns a negative error code if any error occurs during operation.
1811  * The available space is stored on availp.  When err = 0 and avail = 0
1812  * on the capture stream, it indicates the stream is in DRAINING state.
1813  */
wait_for_avail(struct snd_pcm_substream * substream,snd_pcm_uframes_t * availp)1814 static int wait_for_avail(struct snd_pcm_substream *substream,
1815 			      snd_pcm_uframes_t *availp)
1816 {
1817 	struct snd_pcm_runtime *runtime = substream->runtime;
1818 	int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1819 	wait_queue_entry_t wait;
1820 	int err = 0;
1821 	snd_pcm_uframes_t avail = 0;
1822 	long wait_time, tout;
1823 
1824 	init_waitqueue_entry(&wait, current);
1825 	set_current_state(TASK_INTERRUPTIBLE);
1826 	add_wait_queue(&runtime->tsleep, &wait);
1827 
1828 	if (runtime->no_period_wakeup)
1829 		wait_time = MAX_SCHEDULE_TIMEOUT;
1830 	else {
1831 		/* use wait time from substream if available */
1832 		if (substream->wait_time) {
1833 			wait_time = substream->wait_time;
1834 		} else {
1835 			wait_time = 10;
1836 
1837 			if (runtime->rate) {
1838 				long t = runtime->period_size * 2 /
1839 					 runtime->rate;
1840 				wait_time = max(t, wait_time);
1841 			}
1842 			wait_time = msecs_to_jiffies(wait_time * 1000);
1843 		}
1844 	}
1845 
1846 	for (;;) {
1847 		if (signal_pending(current)) {
1848 			err = -ERESTARTSYS;
1849 			break;
1850 		}
1851 
1852 		/*
1853 		 * We need to check if space became available already
1854 		 * (and thus the wakeup happened already) first to close
1855 		 * the race of space already having become available.
1856 		 * This check must happen after been added to the waitqueue
1857 		 * and having current state be INTERRUPTIBLE.
1858 		 */
1859 		avail = snd_pcm_avail(substream);
1860 		if (avail >= runtime->twake)
1861 			break;
1862 		snd_pcm_stream_unlock_irq(substream);
1863 
1864 		tout = schedule_timeout(wait_time);
1865 
1866 		snd_pcm_stream_lock_irq(substream);
1867 		set_current_state(TASK_INTERRUPTIBLE);
1868 		switch (runtime->status->state) {
1869 		case SNDRV_PCM_STATE_SUSPENDED:
1870 			err = -ESTRPIPE;
1871 			goto _endloop;
1872 		case SNDRV_PCM_STATE_XRUN:
1873 			err = -EPIPE;
1874 			goto _endloop;
1875 		case SNDRV_PCM_STATE_DRAINING:
1876 			if (is_playback)
1877 				err = -EPIPE;
1878 			else
1879 				avail = 0; /* indicate draining */
1880 			goto _endloop;
1881 		case SNDRV_PCM_STATE_OPEN:
1882 		case SNDRV_PCM_STATE_SETUP:
1883 		case SNDRV_PCM_STATE_DISCONNECTED:
1884 			err = -EBADFD;
1885 			goto _endloop;
1886 		case SNDRV_PCM_STATE_PAUSED:
1887 			continue;
1888 		}
1889 		if (!tout) {
1890 			pcm_dbg(substream->pcm,
1891 				"%s write error (DMA or IRQ trouble?)\n",
1892 				is_playback ? "playback" : "capture");
1893 			err = -EIO;
1894 			break;
1895 		}
1896 	}
1897  _endloop:
1898 	set_current_state(TASK_RUNNING);
1899 	remove_wait_queue(&runtime->tsleep, &wait);
1900 	*availp = avail;
1901 	return err;
1902 }
1903 
1904 typedef int (*pcm_transfer_f)(struct snd_pcm_substream *substream,
1905 			      int channel, unsigned long hwoff,
1906 			      void *buf, unsigned long bytes);
1907 
1908 typedef int (*pcm_copy_f)(struct snd_pcm_substream *, snd_pcm_uframes_t, void *,
1909 			  snd_pcm_uframes_t, snd_pcm_uframes_t, pcm_transfer_f);
1910 
1911 /* calculate the target DMA-buffer position to be written/read */
get_dma_ptr(struct snd_pcm_runtime * runtime,int channel,unsigned long hwoff)1912 static void *get_dma_ptr(struct snd_pcm_runtime *runtime,
1913 			   int channel, unsigned long hwoff)
1914 {
1915 	return runtime->dma_area + hwoff +
1916 		channel * (runtime->dma_bytes / runtime->channels);
1917 }
1918 
1919 /* default copy_user ops for write; used for both interleaved and non- modes */
default_write_copy(struct snd_pcm_substream * substream,int channel,unsigned long hwoff,void * buf,unsigned long bytes)1920 static int default_write_copy(struct snd_pcm_substream *substream,
1921 			      int channel, unsigned long hwoff,
1922 			      void *buf, unsigned long bytes)
1923 {
1924 	if (copy_from_user(get_dma_ptr(substream->runtime, channel, hwoff),
1925 			   (void __user *)buf, bytes))
1926 		return -EFAULT;
1927 	return 0;
1928 }
1929 
1930 /* default copy_kernel ops for write */
default_write_copy_kernel(struct snd_pcm_substream * substream,int channel,unsigned long hwoff,void * buf,unsigned long bytes)1931 static int default_write_copy_kernel(struct snd_pcm_substream *substream,
1932 				     int channel, unsigned long hwoff,
1933 				     void *buf, unsigned long bytes)
1934 {
1935 	memcpy(get_dma_ptr(substream->runtime, channel, hwoff), buf, bytes);
1936 	return 0;
1937 }
1938 
1939 /* fill silence instead of copy data; called as a transfer helper
1940  * from __snd_pcm_lib_write() or directly from noninterleaved_copy() when
1941  * a NULL buffer is passed
1942  */
fill_silence(struct snd_pcm_substream * substream,int channel,unsigned long hwoff,void * buf,unsigned long bytes)1943 static int fill_silence(struct snd_pcm_substream *substream, int channel,
1944 			unsigned long hwoff, void *buf, unsigned long bytes)
1945 {
1946 	struct snd_pcm_runtime *runtime = substream->runtime;
1947 
1948 	if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
1949 		return 0;
1950 	if (substream->ops->fill_silence)
1951 		return substream->ops->fill_silence(substream, channel,
1952 						    hwoff, bytes);
1953 
1954 	snd_pcm_format_set_silence(runtime->format,
1955 				   get_dma_ptr(runtime, channel, hwoff),
1956 				   bytes_to_samples(runtime, bytes));
1957 	return 0;
1958 }
1959 
1960 /* default copy_user ops for read; used for both interleaved and non- modes */
default_read_copy(struct snd_pcm_substream * substream,int channel,unsigned long hwoff,void * buf,unsigned long bytes)1961 static int default_read_copy(struct snd_pcm_substream *substream,
1962 			     int channel, unsigned long hwoff,
1963 			     void *buf, unsigned long bytes)
1964 {
1965 	if (copy_to_user((void __user *)buf,
1966 			 get_dma_ptr(substream->runtime, channel, hwoff),
1967 			 bytes))
1968 		return -EFAULT;
1969 	return 0;
1970 }
1971 
1972 /* default copy_kernel ops for read */
default_read_copy_kernel(struct snd_pcm_substream * substream,int channel,unsigned long hwoff,void * buf,unsigned long bytes)1973 static int default_read_copy_kernel(struct snd_pcm_substream *substream,
1974 				    int channel, unsigned long hwoff,
1975 				    void *buf, unsigned long bytes)
1976 {
1977 	memcpy(buf, get_dma_ptr(substream->runtime, channel, hwoff), bytes);
1978 	return 0;
1979 }
1980 
1981 /* call transfer function with the converted pointers and sizes;
1982  * for interleaved mode, it's one shot for all samples
1983  */
interleaved_copy(struct snd_pcm_substream * substream,snd_pcm_uframes_t hwoff,void * data,snd_pcm_uframes_t off,snd_pcm_uframes_t frames,pcm_transfer_f transfer)1984 static int interleaved_copy(struct snd_pcm_substream *substream,
1985 			    snd_pcm_uframes_t hwoff, void *data,
1986 			    snd_pcm_uframes_t off,
1987 			    snd_pcm_uframes_t frames,
1988 			    pcm_transfer_f transfer)
1989 {
1990 	struct snd_pcm_runtime *runtime = substream->runtime;
1991 
1992 	/* convert to bytes */
1993 	hwoff = frames_to_bytes(runtime, hwoff);
1994 	off = frames_to_bytes(runtime, off);
1995 	frames = frames_to_bytes(runtime, frames);
1996 	return transfer(substream, 0, hwoff, data + off, frames);
1997 }
1998 
1999 /* call transfer function with the converted pointers and sizes for each
2000  * non-interleaved channel; when buffer is NULL, silencing instead of copying
2001  */
noninterleaved_copy(struct snd_pcm_substream * substream,snd_pcm_uframes_t hwoff,void * data,snd_pcm_uframes_t off,snd_pcm_uframes_t frames,pcm_transfer_f transfer)2002 static int noninterleaved_copy(struct snd_pcm_substream *substream,
2003 			       snd_pcm_uframes_t hwoff, void *data,
2004 			       snd_pcm_uframes_t off,
2005 			       snd_pcm_uframes_t frames,
2006 			       pcm_transfer_f transfer)
2007 {
2008 	struct snd_pcm_runtime *runtime = substream->runtime;
2009 	int channels = runtime->channels;
2010 	void **bufs = data;
2011 	int c, err;
2012 
2013 	/* convert to bytes; note that it's not frames_to_bytes() here.
2014 	 * in non-interleaved mode, we copy for each channel, thus
2015 	 * each copy is n_samples bytes x channels = whole frames.
2016 	 */
2017 	off = samples_to_bytes(runtime, off);
2018 	frames = samples_to_bytes(runtime, frames);
2019 	hwoff = samples_to_bytes(runtime, hwoff);
2020 	for (c = 0; c < channels; ++c, ++bufs) {
2021 		if (!data || !*bufs)
2022 			err = fill_silence(substream, c, hwoff, NULL, frames);
2023 		else
2024 			err = transfer(substream, c, hwoff, *bufs + off,
2025 				       frames);
2026 		if (err < 0)
2027 			return err;
2028 	}
2029 	return 0;
2030 }
2031 
2032 /* fill silence on the given buffer position;
2033  * called from snd_pcm_playback_silence()
2034  */
fill_silence_frames(struct snd_pcm_substream * substream,snd_pcm_uframes_t off,snd_pcm_uframes_t frames)2035 static int fill_silence_frames(struct snd_pcm_substream *substream,
2036 			       snd_pcm_uframes_t off, snd_pcm_uframes_t frames)
2037 {
2038 	if (substream->runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
2039 	    substream->runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED)
2040 		return interleaved_copy(substream, off, NULL, 0, frames,
2041 					fill_silence);
2042 	else
2043 		return noninterleaved_copy(substream, off, NULL, 0, frames,
2044 					   fill_silence);
2045 }
2046 
2047 /* sanity-check for read/write methods */
pcm_sanity_check(struct snd_pcm_substream * substream)2048 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2049 {
2050 	struct snd_pcm_runtime *runtime;
2051 	if (PCM_RUNTIME_CHECK(substream))
2052 		return -ENXIO;
2053 	if (substream->hw_no_buffer)
2054 		snd_printd("%s: warning this PCM is host less\n", __func__);
2055 	runtime = substream->runtime;
2056 	if (snd_BUG_ON(!substream->ops->copy_user && !runtime->dma_area))
2057 		return -EINVAL;
2058 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2059 		return -EBADFD;
2060 	return 0;
2061 }
2062 
pcm_accessible_state(struct snd_pcm_runtime * runtime)2063 static int pcm_accessible_state(struct snd_pcm_runtime *runtime)
2064 {
2065 	switch (runtime->status->state) {
2066 	case SNDRV_PCM_STATE_PREPARED:
2067 	case SNDRV_PCM_STATE_RUNNING:
2068 	case SNDRV_PCM_STATE_PAUSED:
2069 		return 0;
2070 	case SNDRV_PCM_STATE_XRUN:
2071 		return -EPIPE;
2072 	case SNDRV_PCM_STATE_SUSPENDED:
2073 		return -ESTRPIPE;
2074 	default:
2075 		return -EBADFD;
2076 	}
2077 }
2078 
2079 /* update to the given appl_ptr and call ack callback if needed;
2080  * when an error is returned, take back to the original value
2081  */
pcm_lib_apply_appl_ptr(struct snd_pcm_substream * substream,snd_pcm_uframes_t appl_ptr)2082 int pcm_lib_apply_appl_ptr(struct snd_pcm_substream *substream,
2083 			   snd_pcm_uframes_t appl_ptr)
2084 {
2085 	struct snd_pcm_runtime *runtime = substream->runtime;
2086 	snd_pcm_uframes_t old_appl_ptr = runtime->control->appl_ptr;
2087 	int ret;
2088 
2089 	if (old_appl_ptr == appl_ptr)
2090 		return 0;
2091 
2092 	runtime->control->appl_ptr = appl_ptr;
2093 	if (substream->ops->ack) {
2094 		ret = substream->ops->ack(substream);
2095 		if (ret < 0) {
2096 			runtime->control->appl_ptr = old_appl_ptr;
2097 			return ret;
2098 		}
2099 	}
2100 
2101 	trace_applptr(substream, old_appl_ptr, appl_ptr);
2102 
2103 	return 0;
2104 }
2105 
2106 /* the common loop for read/write data */
__snd_pcm_lib_xfer(struct snd_pcm_substream * substream,void * data,bool interleaved,snd_pcm_uframes_t size,bool in_kernel)2107 snd_pcm_sframes_t __snd_pcm_lib_xfer(struct snd_pcm_substream *substream,
2108 				     void *data, bool interleaved,
2109 				     snd_pcm_uframes_t size, bool in_kernel)
2110 {
2111 	struct snd_pcm_runtime *runtime = substream->runtime;
2112 	snd_pcm_uframes_t xfer = 0;
2113 	snd_pcm_uframes_t offset = 0;
2114 	snd_pcm_uframes_t avail;
2115 	pcm_copy_f writer;
2116 	pcm_transfer_f transfer;
2117 	bool nonblock;
2118 	bool is_playback;
2119 	int err;
2120 
2121 	err = pcm_sanity_check(substream);
2122 	if (err < 0)
2123 		return err;
2124 
2125 	is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
2126 	if (interleaved) {
2127 		if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2128 		    runtime->channels > 1)
2129 			return -EINVAL;
2130 		writer = interleaved_copy;
2131 	} else {
2132 		if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2133 			return -EINVAL;
2134 		writer = noninterleaved_copy;
2135 	}
2136 
2137 	if (!data) {
2138 		if (is_playback)
2139 			transfer = fill_silence;
2140 		else
2141 			return -EINVAL;
2142 	} else if (in_kernel) {
2143 		if (substream->ops->copy_kernel)
2144 			transfer = substream->ops->copy_kernel;
2145 		else
2146 			transfer = is_playback ?
2147 				default_write_copy_kernel : default_read_copy_kernel;
2148 	} else {
2149 		if (substream->ops->copy_user)
2150 			transfer = (pcm_transfer_f)substream->ops->copy_user;
2151 		else
2152 			transfer = is_playback ?
2153 				default_write_copy : default_read_copy;
2154 	}
2155 
2156 	if (size == 0)
2157 		return 0;
2158 
2159 	nonblock = !!(substream->f_flags & O_NONBLOCK);
2160 
2161 	snd_pcm_stream_lock_irq(substream);
2162 	err = pcm_accessible_state(runtime);
2163 	if (err < 0)
2164 		goto _end_unlock;
2165 
2166 	runtime->twake = runtime->control->avail_min ? : 1;
2167 	if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2168 		snd_pcm_update_hw_ptr(substream);
2169 
2170 	/*
2171 	 * If size < start_threshold, wait indefinitely. Another
2172 	 * thread may start capture
2173 	 */
2174 	if (!is_playback &&
2175 	    runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2176 	    size >= runtime->start_threshold) {
2177 		err = snd_pcm_start(substream);
2178 		if (err < 0)
2179 			goto _end_unlock;
2180 	}
2181 
2182 	avail = snd_pcm_avail(substream);
2183 
2184 	while (size > 0) {
2185 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2186 		snd_pcm_uframes_t cont;
2187 		if (!avail) {
2188 			if (!is_playback &&
2189 			    runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
2190 				snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2191 				goto _end_unlock;
2192 			}
2193 			if (nonblock) {
2194 				err = -EAGAIN;
2195 				goto _end_unlock;
2196 			}
2197 			runtime->twake = min_t(snd_pcm_uframes_t, size,
2198 					runtime->control->avail_min ? : 1);
2199 			err = wait_for_avail(substream, &avail);
2200 			if (err < 0)
2201 				goto _end_unlock;
2202 			if (!avail)
2203 				continue; /* draining */
2204 		}
2205 		frames = size > avail ? avail : size;
2206 		appl_ptr = READ_ONCE(runtime->control->appl_ptr);
2207 		appl_ofs = appl_ptr % runtime->buffer_size;
2208 		cont = runtime->buffer_size - appl_ofs;
2209 		if (frames > cont)
2210 			frames = cont;
2211 		if (snd_BUG_ON(!frames)) {
2212 			err = -EINVAL;
2213 			goto _end_unlock;
2214 		}
2215 		snd_pcm_stream_unlock_irq(substream);
2216 		err = writer(substream, appl_ofs, data, offset, frames,
2217 			     transfer);
2218 		snd_pcm_stream_lock_irq(substream);
2219 		if (err < 0)
2220 			goto _end_unlock;
2221 		err = pcm_accessible_state(runtime);
2222 		if (err < 0)
2223 			goto _end_unlock;
2224 		appl_ptr += frames;
2225 		if (appl_ptr >= runtime->boundary)
2226 			appl_ptr -= runtime->boundary;
2227 		err = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2228 		if (err < 0)
2229 			goto _end_unlock;
2230 
2231 		offset += frames;
2232 		size -= frames;
2233 		xfer += frames;
2234 		avail -= frames;
2235 		if (is_playback &&
2236 		    runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2237 		    snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2238 			err = snd_pcm_start(substream);
2239 			if (err < 0)
2240 				goto _end_unlock;
2241 		}
2242 	}
2243  _end_unlock:
2244 	runtime->twake = 0;
2245 	if (xfer > 0 && err >= 0)
2246 		snd_pcm_update_state(substream, runtime);
2247 	snd_pcm_stream_unlock_irq(substream);
2248 	return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2249 }
2250 EXPORT_SYMBOL(__snd_pcm_lib_xfer);
2251 
2252 /*
2253  * standard channel mapping helpers
2254  */
2255 
2256 /* default channel maps for multi-channel playbacks, up to 8 channels */
2257 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2258 	{ .channels = 1,
2259 	  .map = { SNDRV_CHMAP_MONO } },
2260 	{ .channels = 2,
2261 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2262 	{ .channels = 4,
2263 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2264 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2265 	{ .channels = 6,
2266 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2267 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2268 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2269 	{ .channels = 8,
2270 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2271 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2272 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2273 		   SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2274 	{ }
2275 };
2276 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2277 
2278 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2279 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2280 	{ .channels = 1,
2281 	  .map = { SNDRV_CHMAP_MONO } },
2282 	{ .channels = 2,
2283 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2284 	{ .channels = 4,
2285 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2286 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2287 	{ .channels = 6,
2288 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2289 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2290 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2291 	{ .channels = 8,
2292 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2293 		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2294 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2295 		   SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2296 	{ }
2297 };
2298 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2299 
valid_chmap_channels(const struct snd_pcm_chmap * info,int ch)2300 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2301 {
2302 	if (ch > info->max_channels)
2303 		return false;
2304 	return !info->channel_mask || (info->channel_mask & (1U << ch));
2305 }
2306 
pcm_chmap_ctl_info(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_info * uinfo)2307 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2308 			      struct snd_ctl_elem_info *uinfo)
2309 {
2310 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2311 
2312 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2313 	uinfo->count = 0;
2314 	uinfo->count = info->max_channels;
2315 	uinfo->value.integer.min = 0;
2316 	uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2317 	return 0;
2318 }
2319 
2320 /* get callback for channel map ctl element
2321  * stores the channel position firstly matching with the current channels
2322  */
pcm_chmap_ctl_get(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_value * ucontrol)2323 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2324 			     struct snd_ctl_elem_value *ucontrol)
2325 {
2326 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2327 	unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2328 	struct snd_pcm_substream *substream;
2329 	const struct snd_pcm_chmap_elem *map;
2330 
2331 	if (!info->chmap)
2332 		return -EINVAL;
2333 	substream = snd_pcm_chmap_substream(info, idx);
2334 	if (!substream)
2335 		return -ENODEV;
2336 	memset(ucontrol->value.integer.value, 0,
2337 	       sizeof(ucontrol->value.integer.value));
2338 	if (!substream->runtime)
2339 		return 0; /* no channels set */
2340 	for (map = info->chmap; map->channels; map++) {
2341 		int i;
2342 		if (map->channels == substream->runtime->channels &&
2343 		    valid_chmap_channels(info, map->channels)) {
2344 			for (i = 0; i < map->channels; i++)
2345 				ucontrol->value.integer.value[i] = map->map[i];
2346 			return 0;
2347 		}
2348 	}
2349 	return -EINVAL;
2350 }
2351 
2352 /* tlv callback for channel map ctl element
2353  * expands the pre-defined channel maps in a form of TLV
2354  */
pcm_chmap_ctl_tlv(struct snd_kcontrol * kcontrol,int op_flag,unsigned int size,unsigned int __user * tlv)2355 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2356 			     unsigned int size, unsigned int __user *tlv)
2357 {
2358 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2359 	const struct snd_pcm_chmap_elem *map;
2360 	unsigned int __user *dst;
2361 	int c, count = 0;
2362 
2363 	if (!info->chmap)
2364 		return -EINVAL;
2365 	if (size < 8)
2366 		return -ENOMEM;
2367 	if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2368 		return -EFAULT;
2369 	size -= 8;
2370 	dst = tlv + 2;
2371 	for (map = info->chmap; map->channels; map++) {
2372 		int chs_bytes = map->channels * 4;
2373 		if (!valid_chmap_channels(info, map->channels))
2374 			continue;
2375 		if (size < 8)
2376 			return -ENOMEM;
2377 		if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2378 		    put_user(chs_bytes, dst + 1))
2379 			return -EFAULT;
2380 		dst += 2;
2381 		size -= 8;
2382 		count += 8;
2383 		if (size < chs_bytes)
2384 			return -ENOMEM;
2385 		size -= chs_bytes;
2386 		count += chs_bytes;
2387 		for (c = 0; c < map->channels; c++) {
2388 			if (put_user(map->map[c], dst))
2389 				return -EFAULT;
2390 			dst++;
2391 		}
2392 	}
2393 	if (put_user(count, tlv + 1))
2394 		return -EFAULT;
2395 	return 0;
2396 }
2397 
pcm_chmap_ctl_private_free(struct snd_kcontrol * kcontrol)2398 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2399 {
2400 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2401 	info->pcm->streams[info->stream].chmap_kctl = NULL;
2402 	kfree(info);
2403 }
2404 
2405 /**
2406  * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2407  * @pcm: the assigned PCM instance
2408  * @stream: stream direction
2409  * @chmap: channel map elements (for query)
2410  * @max_channels: the max number of channels for the stream
2411  * @private_value: the value passed to each kcontrol's private_value field
2412  * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2413  *
2414  * Create channel-mapping control elements assigned to the given PCM stream(s).
2415  * Return: Zero if successful, or a negative error value.
2416  */
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)2417 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2418 			   const struct snd_pcm_chmap_elem *chmap,
2419 			   int max_channels,
2420 			   unsigned long private_value,
2421 			   struct snd_pcm_chmap **info_ret)
2422 {
2423 	struct snd_pcm_chmap *info;
2424 	struct snd_kcontrol_new knew = {
2425 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
2426 		.access = SNDRV_CTL_ELEM_ACCESS_READ |
2427 			SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2428 			SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2429 		.info = pcm_chmap_ctl_info,
2430 		.get = pcm_chmap_ctl_get,
2431 		.tlv.c = pcm_chmap_ctl_tlv,
2432 	};
2433 	int err;
2434 
2435 	if (WARN_ON(pcm->streams[stream].chmap_kctl))
2436 		return -EBUSY;
2437 	info = kzalloc(sizeof(*info), GFP_KERNEL);
2438 	if (!info)
2439 		return -ENOMEM;
2440 	info->pcm = pcm;
2441 	info->stream = stream;
2442 	info->chmap = chmap;
2443 	info->max_channels = max_channels;
2444 	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2445 		knew.name = "Playback Channel Map";
2446 	else
2447 		knew.name = "Capture Channel Map";
2448 	knew.device = pcm->device;
2449 	knew.count = pcm->streams[stream].substream_count;
2450 	knew.private_value = private_value;
2451 	info->kctl = snd_ctl_new1(&knew, info);
2452 	if (!info->kctl) {
2453 		kfree(info);
2454 		return -ENOMEM;
2455 	}
2456 	info->kctl->private_free = pcm_chmap_ctl_private_free;
2457 	err = snd_ctl_add(pcm->card, info->kctl);
2458 	if (err < 0)
2459 		return err;
2460 	pcm->streams[stream].chmap_kctl = info->kctl;
2461 	if (info_ret)
2462 		*info_ret = info;
2463 	return 0;
2464 }
2465 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);
2466