xref: /linux/sound/core/pcm_lib.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
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 <sound/core.h>
27 #include <sound/control.h>
28 #include <sound/info.h>
29 #include <sound/pcm.h>
30 #include <sound/pcm_params.h>
31 #include <sound/timer.h>
32 
33 /*
34  * fill ring buffer with silence
35  * runtime->silence_start: starting pointer to silence area
36  * runtime->silence_filled: size filled with silence
37  * runtime->silence_threshold: threshold from application
38  * runtime->silence_size: maximal size from application
39  *
40  * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
41  */
42 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
43 {
44 	struct snd_pcm_runtime *runtime = substream->runtime;
45 	snd_pcm_uframes_t frames, ofs, transfer;
46 
47 	if (runtime->silence_size < runtime->boundary) {
48 		snd_pcm_sframes_t noise_dist, n;
49 		if (runtime->silence_start != runtime->control->appl_ptr) {
50 			n = runtime->control->appl_ptr - runtime->silence_start;
51 			if (n < 0)
52 				n += runtime->boundary;
53 			if ((snd_pcm_uframes_t)n < runtime->silence_filled)
54 				runtime->silence_filled -= n;
55 			else
56 				runtime->silence_filled = 0;
57 			runtime->silence_start = runtime->control->appl_ptr;
58 		}
59 		if (runtime->silence_filled >= runtime->buffer_size)
60 			return;
61 		noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
62 		if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
63 			return;
64 		frames = runtime->silence_threshold - noise_dist;
65 		if (frames > runtime->silence_size)
66 			frames = runtime->silence_size;
67 	} else {
68 		if (new_hw_ptr == ULONG_MAX) {	/* initialization */
69 			snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
70 			if (avail > runtime->buffer_size)
71 				avail = runtime->buffer_size;
72 			runtime->silence_filled = avail > 0 ? avail : 0;
73 			runtime->silence_start = (runtime->status->hw_ptr +
74 						  runtime->silence_filled) %
75 						 runtime->boundary;
76 		} else {
77 			ofs = runtime->status->hw_ptr;
78 			frames = new_hw_ptr - ofs;
79 			if ((snd_pcm_sframes_t)frames < 0)
80 				frames += runtime->boundary;
81 			runtime->silence_filled -= frames;
82 			if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
83 				runtime->silence_filled = 0;
84 				runtime->silence_start = new_hw_ptr;
85 			} else {
86 				runtime->silence_start = ofs;
87 			}
88 		}
89 		frames = runtime->buffer_size - runtime->silence_filled;
90 	}
91 	if (snd_BUG_ON(frames > runtime->buffer_size))
92 		return;
93 	if (frames == 0)
94 		return;
95 	ofs = runtime->silence_start % runtime->buffer_size;
96 	while (frames > 0) {
97 		transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
98 		if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
99 		    runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
100 			if (substream->ops->silence) {
101 				int err;
102 				err = substream->ops->silence(substream, -1, ofs, transfer);
103 				snd_BUG_ON(err < 0);
104 			} else {
105 				char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
106 				snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
107 			}
108 		} else {
109 			unsigned int c;
110 			unsigned int channels = runtime->channels;
111 			if (substream->ops->silence) {
112 				for (c = 0; c < channels; ++c) {
113 					int err;
114 					err = substream->ops->silence(substream, c, ofs, transfer);
115 					snd_BUG_ON(err < 0);
116 				}
117 			} else {
118 				size_t dma_csize = runtime->dma_bytes / channels;
119 				for (c = 0; c < channels; ++c) {
120 					char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
121 					snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
122 				}
123 			}
124 		}
125 		runtime->silence_filled += transfer;
126 		frames -= transfer;
127 		ofs = 0;
128 	}
129 }
130 
131 static void pcm_debug_name(struct snd_pcm_substream *substream,
132 			   char *name, size_t len)
133 {
134 	snprintf(name, len, "pcmC%dD%d%c:%d",
135 		 substream->pcm->card->number,
136 		 substream->pcm->device,
137 		 substream->stream ? 'c' : 'p',
138 		 substream->number);
139 }
140 
141 #define XRUN_DEBUG_BASIC	(1<<0)
142 #define XRUN_DEBUG_STACK	(1<<1)	/* dump also stack */
143 #define XRUN_DEBUG_JIFFIESCHECK	(1<<2)	/* do jiffies check */
144 #define XRUN_DEBUG_PERIODUPDATE	(1<<3)	/* full period update info */
145 #define XRUN_DEBUG_HWPTRUPDATE	(1<<4)	/* full hwptr update info */
146 #define XRUN_DEBUG_LOG		(1<<5)	/* show last 10 positions on err */
147 #define XRUN_DEBUG_LOGONCE	(1<<6)	/* do above only once */
148 
149 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
150 
151 #define xrun_debug(substream, mask) \
152 			((substream)->pstr->xrun_debug & (mask))
153 #else
154 #define xrun_debug(substream, mask)	0
155 #endif
156 
157 #define dump_stack_on_xrun(substream) do {			\
158 		if (xrun_debug(substream, XRUN_DEBUG_STACK))	\
159 			dump_stack();				\
160 	} while (0)
161 
162 static void xrun(struct snd_pcm_substream *substream)
163 {
164 	struct snd_pcm_runtime *runtime = substream->runtime;
165 
166 	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
167 		snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
168 	snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
169 	if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
170 		char name[16];
171 		pcm_debug_name(substream, name, sizeof(name));
172 		snd_printd(KERN_DEBUG "XRUN: %s\n", name);
173 		dump_stack_on_xrun(substream);
174 	}
175 }
176 
177 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
178 #define hw_ptr_error(substream, fmt, args...)				\
179 	do {								\
180 		if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {		\
181 			xrun_log_show(substream);			\
182 			if (printk_ratelimit()) {			\
183 				snd_printd("PCM: " fmt, ##args);	\
184 			}						\
185 			dump_stack_on_xrun(substream);			\
186 		}							\
187 	} while (0)
188 
189 #define XRUN_LOG_CNT	10
190 
191 struct hwptr_log_entry {
192 	unsigned long jiffies;
193 	snd_pcm_uframes_t pos;
194 	snd_pcm_uframes_t period_size;
195 	snd_pcm_uframes_t buffer_size;
196 	snd_pcm_uframes_t old_hw_ptr;
197 	snd_pcm_uframes_t hw_ptr_base;
198 };
199 
200 struct snd_pcm_hwptr_log {
201 	unsigned int idx;
202 	unsigned int hit: 1;
203 	struct hwptr_log_entry entries[XRUN_LOG_CNT];
204 };
205 
206 static void xrun_log(struct snd_pcm_substream *substream,
207 		     snd_pcm_uframes_t pos)
208 {
209 	struct snd_pcm_runtime *runtime = substream->runtime;
210 	struct snd_pcm_hwptr_log *log = runtime->hwptr_log;
211 	struct hwptr_log_entry *entry;
212 
213 	if (log == NULL) {
214 		log = kzalloc(sizeof(*log), GFP_ATOMIC);
215 		if (log == NULL)
216 			return;
217 		runtime->hwptr_log = log;
218 	} else {
219 		if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
220 			return;
221 	}
222 	entry = &log->entries[log->idx];
223 	entry->jiffies = jiffies;
224 	entry->pos = pos;
225 	entry->period_size = runtime->period_size;
226 	entry->buffer_size = runtime->buffer_size;;
227 	entry->old_hw_ptr = runtime->status->hw_ptr;
228 	entry->hw_ptr_base = runtime->hw_ptr_base;
229 	log->idx = (log->idx + 1) % XRUN_LOG_CNT;
230 }
231 
232 static void xrun_log_show(struct snd_pcm_substream *substream)
233 {
234 	struct snd_pcm_hwptr_log *log = substream->runtime->hwptr_log;
235 	struct hwptr_log_entry *entry;
236 	char name[16];
237 	unsigned int idx;
238 	int cnt;
239 
240 	if (log == NULL)
241 		return;
242 	if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
243 		return;
244 	pcm_debug_name(substream, name, sizeof(name));
245 	for (cnt = 0, idx = log->idx; cnt < XRUN_LOG_CNT; cnt++) {
246 		entry = &log->entries[idx];
247 		if (entry->period_size == 0)
248 			break;
249 		snd_printd("hwptr log: %s: j=%lu, pos=%ld/%ld/%ld, "
250 			   "hwptr=%ld/%ld\n",
251 			   name, entry->jiffies, (unsigned long)entry->pos,
252 			   (unsigned long)entry->period_size,
253 			   (unsigned long)entry->buffer_size,
254 			   (unsigned long)entry->old_hw_ptr,
255 			   (unsigned long)entry->hw_ptr_base);
256 		idx++;
257 		idx %= XRUN_LOG_CNT;
258 	}
259 	log->hit = 1;
260 }
261 
262 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
263 
264 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
265 #define xrun_log(substream, pos)	do { } while (0)
266 #define xrun_log_show(substream)	do { } while (0)
267 
268 #endif
269 
270 int snd_pcm_update_state(struct snd_pcm_substream *substream,
271 			 struct snd_pcm_runtime *runtime)
272 {
273 	snd_pcm_uframes_t avail;
274 
275 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
276 		avail = snd_pcm_playback_avail(runtime);
277 	else
278 		avail = snd_pcm_capture_avail(runtime);
279 	if (avail > runtime->avail_max)
280 		runtime->avail_max = avail;
281 	if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
282 		if (avail >= runtime->buffer_size) {
283 			snd_pcm_drain_done(substream);
284 			return -EPIPE;
285 		}
286 	} else {
287 		if (avail >= runtime->stop_threshold) {
288 			xrun(substream);
289 			return -EPIPE;
290 		}
291 	}
292 	if (runtime->twake) {
293 		if (avail >= runtime->twake)
294 			wake_up(&runtime->tsleep);
295 	} else if (avail >= runtime->control->avail_min)
296 		wake_up(&runtime->sleep);
297 	return 0;
298 }
299 
300 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
301 				  unsigned int in_interrupt)
302 {
303 	struct snd_pcm_runtime *runtime = substream->runtime;
304 	snd_pcm_uframes_t pos;
305 	snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
306 	snd_pcm_sframes_t hdelta, delta;
307 	unsigned long jdelta;
308 
309 	old_hw_ptr = runtime->status->hw_ptr;
310 	pos = substream->ops->pointer(substream);
311 	if (pos == SNDRV_PCM_POS_XRUN) {
312 		xrun(substream);
313 		return -EPIPE;
314 	}
315 	if (pos >= runtime->buffer_size) {
316 		if (printk_ratelimit()) {
317 			char name[16];
318 			pcm_debug_name(substream, name, sizeof(name));
319 			xrun_log_show(substream);
320 			snd_printd(KERN_ERR  "BUG: %s, pos = %ld, "
321 				   "buffer size = %ld, period size = %ld\n",
322 				   name, pos, runtime->buffer_size,
323 				   runtime->period_size);
324 		}
325 		pos = 0;
326 	}
327 	pos -= pos % runtime->min_align;
328 	if (xrun_debug(substream, XRUN_DEBUG_LOG))
329 		xrun_log(substream, pos);
330 	hw_base = runtime->hw_ptr_base;
331 	new_hw_ptr = hw_base + pos;
332 	if (in_interrupt) {
333 		/* we know that one period was processed */
334 		/* delta = "expected next hw_ptr" for in_interrupt != 0 */
335 		delta = runtime->hw_ptr_interrupt + runtime->period_size;
336 		if (delta > new_hw_ptr) {
337 			hw_base += runtime->buffer_size;
338 			if (hw_base >= runtime->boundary)
339 				hw_base = 0;
340 			new_hw_ptr = hw_base + pos;
341 			goto __delta;
342 		}
343 	}
344 	/* new_hw_ptr might be lower than old_hw_ptr in case when */
345 	/* pointer crosses the end of the ring buffer */
346 	if (new_hw_ptr < old_hw_ptr) {
347 		hw_base += runtime->buffer_size;
348 		if (hw_base >= runtime->boundary)
349 			hw_base = 0;
350 		new_hw_ptr = hw_base + pos;
351 	}
352       __delta:
353 	delta = new_hw_ptr - old_hw_ptr;
354 	if (delta < 0)
355 		delta += runtime->boundary;
356 	if (xrun_debug(substream, in_interrupt ?
357 			XRUN_DEBUG_PERIODUPDATE : XRUN_DEBUG_HWPTRUPDATE)) {
358 		char name[16];
359 		pcm_debug_name(substream, name, sizeof(name));
360 		snd_printd("%s_update: %s: pos=%u/%u/%u, "
361 			   "hwptr=%ld/%ld/%ld/%ld\n",
362 			   in_interrupt ? "period" : "hwptr",
363 			   name,
364 			   (unsigned int)pos,
365 			   (unsigned int)runtime->period_size,
366 			   (unsigned int)runtime->buffer_size,
367 			   (unsigned long)delta,
368 			   (unsigned long)old_hw_ptr,
369 			   (unsigned long)new_hw_ptr,
370 			   (unsigned long)runtime->hw_ptr_base);
371 	}
372 	/* something must be really wrong */
373 	if (delta >= runtime->buffer_size + runtime->period_size) {
374 		hw_ptr_error(substream,
375 			       "Unexpected hw_pointer value %s"
376 			       "(stream=%i, pos=%ld, new_hw_ptr=%ld, "
377 			       "old_hw_ptr=%ld)\n",
378 				     in_interrupt ? "[Q] " : "[P]",
379 				     substream->stream, (long)pos,
380 				     (long)new_hw_ptr, (long)old_hw_ptr);
381 		return 0;
382 	}
383 
384 	/* Do jiffies check only in xrun_debug mode */
385 	if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
386 		goto no_jiffies_check;
387 
388 	/* Skip the jiffies check for hardwares with BATCH flag.
389 	 * Such hardware usually just increases the position at each IRQ,
390 	 * thus it can't give any strange position.
391 	 */
392 	if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
393 		goto no_jiffies_check;
394 	hdelta = delta;
395 	if (hdelta < runtime->delay)
396 		goto no_jiffies_check;
397 	hdelta -= runtime->delay;
398 	jdelta = jiffies - runtime->hw_ptr_jiffies;
399 	if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
400 		delta = jdelta /
401 			(((runtime->period_size * HZ) / runtime->rate)
402 								+ HZ/100);
403 		/* move new_hw_ptr according jiffies not pos variable */
404 		new_hw_ptr = old_hw_ptr;
405 		hw_base = delta;
406 		/* use loop to avoid checks for delta overflows */
407 		/* the delta value is small or zero in most cases */
408 		while (delta > 0) {
409 			new_hw_ptr += runtime->period_size;
410 			if (new_hw_ptr >= runtime->boundary)
411 				new_hw_ptr -= runtime->boundary;
412 			delta--;
413 		}
414 		/* align hw_base to buffer_size */
415 		hw_ptr_error(substream,
416 			     "hw_ptr skipping! %s"
417 			     "(pos=%ld, delta=%ld, period=%ld, "
418 			     "jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
419 			     in_interrupt ? "[Q] " : "",
420 			     (long)pos, (long)hdelta,
421 			     (long)runtime->period_size, jdelta,
422 			     ((hdelta * HZ) / runtime->rate), hw_base,
423 			     (unsigned long)old_hw_ptr,
424 			     (unsigned long)new_hw_ptr);
425 		/* reset values to proper state */
426 		delta = 0;
427 		hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
428 	}
429  no_jiffies_check:
430 	if (delta > runtime->period_size + runtime->period_size / 2) {
431 		hw_ptr_error(substream,
432 			     "Lost interrupts? %s"
433 			     "(stream=%i, delta=%ld, new_hw_ptr=%ld, "
434 			     "old_hw_ptr=%ld)\n",
435 			     in_interrupt ? "[Q] " : "",
436 			     substream->stream, (long)delta,
437 			     (long)new_hw_ptr,
438 			     (long)old_hw_ptr);
439 	}
440 
441 	if (runtime->status->hw_ptr == new_hw_ptr)
442 		return 0;
443 
444 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
445 	    runtime->silence_size > 0)
446 		snd_pcm_playback_silence(substream, new_hw_ptr);
447 
448 	if (in_interrupt) {
449 		delta = new_hw_ptr - runtime->hw_ptr_interrupt;
450 		if (delta < 0)
451 			delta += runtime->boundary;
452 		delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
453 		runtime->hw_ptr_interrupt += delta;
454 		if (runtime->hw_ptr_interrupt >= runtime->boundary)
455 			runtime->hw_ptr_interrupt -= runtime->boundary;
456 	}
457 	runtime->hw_ptr_base = hw_base;
458 	runtime->status->hw_ptr = new_hw_ptr;
459 	runtime->hw_ptr_jiffies = jiffies;
460 	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
461 		snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
462 
463 	return snd_pcm_update_state(substream, runtime);
464 }
465 
466 /* CAUTION: call it with irq disabled */
467 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
468 {
469 	return snd_pcm_update_hw_ptr0(substream, 0);
470 }
471 
472 /**
473  * snd_pcm_set_ops - set the PCM operators
474  * @pcm: the pcm instance
475  * @direction: stream direction, SNDRV_PCM_STREAM_XXX
476  * @ops: the operator table
477  *
478  * Sets the given PCM operators to the pcm instance.
479  */
480 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction, struct snd_pcm_ops *ops)
481 {
482 	struct snd_pcm_str *stream = &pcm->streams[direction];
483 	struct snd_pcm_substream *substream;
484 
485 	for (substream = stream->substream; substream != NULL; substream = substream->next)
486 		substream->ops = ops;
487 }
488 
489 EXPORT_SYMBOL(snd_pcm_set_ops);
490 
491 /**
492  * snd_pcm_sync - set the PCM sync id
493  * @substream: the pcm substream
494  *
495  * Sets the PCM sync identifier for the card.
496  */
497 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
498 {
499 	struct snd_pcm_runtime *runtime = substream->runtime;
500 
501 	runtime->sync.id32[0] = substream->pcm->card->number;
502 	runtime->sync.id32[1] = -1;
503 	runtime->sync.id32[2] = -1;
504 	runtime->sync.id32[3] = -1;
505 }
506 
507 EXPORT_SYMBOL(snd_pcm_set_sync);
508 
509 /*
510  *  Standard ioctl routine
511  */
512 
513 static inline unsigned int div32(unsigned int a, unsigned int b,
514 				 unsigned int *r)
515 {
516 	if (b == 0) {
517 		*r = 0;
518 		return UINT_MAX;
519 	}
520 	*r = a % b;
521 	return a / b;
522 }
523 
524 static inline unsigned int div_down(unsigned int a, unsigned int b)
525 {
526 	if (b == 0)
527 		return UINT_MAX;
528 	return a / b;
529 }
530 
531 static inline unsigned int div_up(unsigned int a, unsigned int b)
532 {
533 	unsigned int r;
534 	unsigned int q;
535 	if (b == 0)
536 		return UINT_MAX;
537 	q = div32(a, b, &r);
538 	if (r)
539 		++q;
540 	return q;
541 }
542 
543 static inline unsigned int mul(unsigned int a, unsigned int b)
544 {
545 	if (a == 0)
546 		return 0;
547 	if (div_down(UINT_MAX, a) < b)
548 		return UINT_MAX;
549 	return a * b;
550 }
551 
552 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
553 				    unsigned int c, unsigned int *r)
554 {
555 	u_int64_t n = (u_int64_t) a * b;
556 	if (c == 0) {
557 		snd_BUG_ON(!n);
558 		*r = 0;
559 		return UINT_MAX;
560 	}
561 	n = div_u64_rem(n, c, r);
562 	if (n >= UINT_MAX) {
563 		*r = 0;
564 		return UINT_MAX;
565 	}
566 	return n;
567 }
568 
569 /**
570  * snd_interval_refine - refine the interval value of configurator
571  * @i: the interval value to refine
572  * @v: the interval value to refer to
573  *
574  * Refines the interval value with the reference value.
575  * The interval is changed to the range satisfying both intervals.
576  * The interval status (min, max, integer, etc.) are evaluated.
577  *
578  * Returns non-zero if the value is changed, zero if not changed.
579  */
580 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
581 {
582 	int changed = 0;
583 	if (snd_BUG_ON(snd_interval_empty(i)))
584 		return -EINVAL;
585 	if (i->min < v->min) {
586 		i->min = v->min;
587 		i->openmin = v->openmin;
588 		changed = 1;
589 	} else if (i->min == v->min && !i->openmin && v->openmin) {
590 		i->openmin = 1;
591 		changed = 1;
592 	}
593 	if (i->max > v->max) {
594 		i->max = v->max;
595 		i->openmax = v->openmax;
596 		changed = 1;
597 	} else if (i->max == v->max && !i->openmax && v->openmax) {
598 		i->openmax = 1;
599 		changed = 1;
600 	}
601 	if (!i->integer && v->integer) {
602 		i->integer = 1;
603 		changed = 1;
604 	}
605 	if (i->integer) {
606 		if (i->openmin) {
607 			i->min++;
608 			i->openmin = 0;
609 		}
610 		if (i->openmax) {
611 			i->max--;
612 			i->openmax = 0;
613 		}
614 	} else if (!i->openmin && !i->openmax && i->min == i->max)
615 		i->integer = 1;
616 	if (snd_interval_checkempty(i)) {
617 		snd_interval_none(i);
618 		return -EINVAL;
619 	}
620 	return changed;
621 }
622 
623 EXPORT_SYMBOL(snd_interval_refine);
624 
625 static int snd_interval_refine_first(struct snd_interval *i)
626 {
627 	if (snd_BUG_ON(snd_interval_empty(i)))
628 		return -EINVAL;
629 	if (snd_interval_single(i))
630 		return 0;
631 	i->max = i->min;
632 	i->openmax = i->openmin;
633 	if (i->openmax)
634 		i->max++;
635 	return 1;
636 }
637 
638 static int snd_interval_refine_last(struct snd_interval *i)
639 {
640 	if (snd_BUG_ON(snd_interval_empty(i)))
641 		return -EINVAL;
642 	if (snd_interval_single(i))
643 		return 0;
644 	i->min = i->max;
645 	i->openmin = i->openmax;
646 	if (i->openmin)
647 		i->min--;
648 	return 1;
649 }
650 
651 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
652 {
653 	if (a->empty || b->empty) {
654 		snd_interval_none(c);
655 		return;
656 	}
657 	c->empty = 0;
658 	c->min = mul(a->min, b->min);
659 	c->openmin = (a->openmin || b->openmin);
660 	c->max = mul(a->max,  b->max);
661 	c->openmax = (a->openmax || b->openmax);
662 	c->integer = (a->integer && b->integer);
663 }
664 
665 /**
666  * snd_interval_div - refine the interval value with division
667  * @a: dividend
668  * @b: divisor
669  * @c: quotient
670  *
671  * c = a / b
672  *
673  * Returns non-zero if the value is changed, zero if not changed.
674  */
675 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
676 {
677 	unsigned int r;
678 	if (a->empty || b->empty) {
679 		snd_interval_none(c);
680 		return;
681 	}
682 	c->empty = 0;
683 	c->min = div32(a->min, b->max, &r);
684 	c->openmin = (r || a->openmin || b->openmax);
685 	if (b->min > 0) {
686 		c->max = div32(a->max, b->min, &r);
687 		if (r) {
688 			c->max++;
689 			c->openmax = 1;
690 		} else
691 			c->openmax = (a->openmax || b->openmin);
692 	} else {
693 		c->max = UINT_MAX;
694 		c->openmax = 0;
695 	}
696 	c->integer = 0;
697 }
698 
699 /**
700  * snd_interval_muldivk - refine the interval value
701  * @a: dividend 1
702  * @b: dividend 2
703  * @k: divisor (as integer)
704  * @c: result
705   *
706  * c = a * b / k
707  *
708  * Returns non-zero if the value is changed, zero if not changed.
709  */
710 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
711 		      unsigned int k, struct snd_interval *c)
712 {
713 	unsigned int r;
714 	if (a->empty || b->empty) {
715 		snd_interval_none(c);
716 		return;
717 	}
718 	c->empty = 0;
719 	c->min = muldiv32(a->min, b->min, k, &r);
720 	c->openmin = (r || a->openmin || b->openmin);
721 	c->max = muldiv32(a->max, b->max, k, &r);
722 	if (r) {
723 		c->max++;
724 		c->openmax = 1;
725 	} else
726 		c->openmax = (a->openmax || b->openmax);
727 	c->integer = 0;
728 }
729 
730 /**
731  * snd_interval_mulkdiv - refine the interval value
732  * @a: dividend 1
733  * @k: dividend 2 (as integer)
734  * @b: divisor
735  * @c: result
736  *
737  * c = a * k / b
738  *
739  * Returns non-zero if the value is changed, zero if not changed.
740  */
741 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
742 		      const struct snd_interval *b, 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, k, b->max, &r);
751 	c->openmin = (r || a->openmin || b->openmax);
752 	if (b->min > 0) {
753 		c->max = muldiv32(a->max, k, b->min, &r);
754 		if (r) {
755 			c->max++;
756 			c->openmax = 1;
757 		} else
758 			c->openmax = (a->openmax || b->openmin);
759 	} else {
760 		c->max = UINT_MAX;
761 		c->openmax = 0;
762 	}
763 	c->integer = 0;
764 }
765 
766 /* ---- */
767 
768 
769 /**
770  * snd_interval_ratnum - refine the interval value
771  * @i: interval to refine
772  * @rats_count: number of ratnum_t
773  * @rats: ratnum_t array
774  * @nump: pointer to store the resultant numerator
775  * @denp: pointer to store the resultant denominator
776  *
777  * Returns non-zero if the value is changed, zero if not changed.
778  */
779 int snd_interval_ratnum(struct snd_interval *i,
780 			unsigned int rats_count, struct snd_ratnum *rats,
781 			unsigned int *nump, unsigned int *denp)
782 {
783 	unsigned int best_num, best_den;
784 	int best_diff;
785 	unsigned int k;
786 	struct snd_interval t;
787 	int err;
788 	unsigned int result_num, result_den;
789 	int result_diff;
790 
791 	best_num = best_den = best_diff = 0;
792 	for (k = 0; k < rats_count; ++k) {
793 		unsigned int num = rats[k].num;
794 		unsigned int den;
795 		unsigned int q = i->min;
796 		int diff;
797 		if (q == 0)
798 			q = 1;
799 		den = div_up(num, q);
800 		if (den < rats[k].den_min)
801 			continue;
802 		if (den > rats[k].den_max)
803 			den = rats[k].den_max;
804 		else {
805 			unsigned int r;
806 			r = (den - rats[k].den_min) % rats[k].den_step;
807 			if (r != 0)
808 				den -= r;
809 		}
810 		diff = num - q * den;
811 		if (diff < 0)
812 			diff = -diff;
813 		if (best_num == 0 ||
814 		    diff * best_den < best_diff * den) {
815 			best_diff = diff;
816 			best_den = den;
817 			best_num = num;
818 		}
819 	}
820 	if (best_den == 0) {
821 		i->empty = 1;
822 		return -EINVAL;
823 	}
824 	t.min = div_down(best_num, best_den);
825 	t.openmin = !!(best_num % best_den);
826 
827 	result_num = best_num;
828 	result_diff = best_diff;
829 	result_den = best_den;
830 	best_num = best_den = best_diff = 0;
831 	for (k = 0; k < rats_count; ++k) {
832 		unsigned int num = rats[k].num;
833 		unsigned int den;
834 		unsigned int q = i->max;
835 		int diff;
836 		if (q == 0) {
837 			i->empty = 1;
838 			return -EINVAL;
839 		}
840 		den = div_down(num, q);
841 		if (den > rats[k].den_max)
842 			continue;
843 		if (den < rats[k].den_min)
844 			den = rats[k].den_min;
845 		else {
846 			unsigned int r;
847 			r = (den - rats[k].den_min) % rats[k].den_step;
848 			if (r != 0)
849 				den += rats[k].den_step - r;
850 		}
851 		diff = q * den - num;
852 		if (diff < 0)
853 			diff = -diff;
854 		if (best_num == 0 ||
855 		    diff * best_den < best_diff * den) {
856 			best_diff = diff;
857 			best_den = den;
858 			best_num = num;
859 		}
860 	}
861 	if (best_den == 0) {
862 		i->empty = 1;
863 		return -EINVAL;
864 	}
865 	t.max = div_up(best_num, best_den);
866 	t.openmax = !!(best_num % best_den);
867 	t.integer = 0;
868 	err = snd_interval_refine(i, &t);
869 	if (err < 0)
870 		return err;
871 
872 	if (snd_interval_single(i)) {
873 		if (best_diff * result_den < result_diff * best_den) {
874 			result_num = best_num;
875 			result_den = best_den;
876 		}
877 		if (nump)
878 			*nump = result_num;
879 		if (denp)
880 			*denp = result_den;
881 	}
882 	return err;
883 }
884 
885 EXPORT_SYMBOL(snd_interval_ratnum);
886 
887 /**
888  * snd_interval_ratden - refine the interval value
889  * @i: interval to refine
890  * @rats_count: number of struct ratden
891  * @rats: struct ratden array
892  * @nump: pointer to store the resultant numerator
893  * @denp: pointer to store the resultant denominator
894  *
895  * Returns non-zero if the value is changed, zero if not changed.
896  */
897 static int snd_interval_ratden(struct snd_interval *i,
898 			       unsigned int rats_count, struct snd_ratden *rats,
899 			       unsigned int *nump, unsigned int *denp)
900 {
901 	unsigned int best_num, best_diff, best_den;
902 	unsigned int k;
903 	struct snd_interval t;
904 	int err;
905 
906 	best_num = best_den = best_diff = 0;
907 	for (k = 0; k < rats_count; ++k) {
908 		unsigned int num;
909 		unsigned int den = rats[k].den;
910 		unsigned int q = i->min;
911 		int diff;
912 		num = mul(q, den);
913 		if (num > rats[k].num_max)
914 			continue;
915 		if (num < rats[k].num_min)
916 			num = rats[k].num_max;
917 		else {
918 			unsigned int r;
919 			r = (num - rats[k].num_min) % rats[k].num_step;
920 			if (r != 0)
921 				num += rats[k].num_step - r;
922 		}
923 		diff = num - q * den;
924 		if (best_num == 0 ||
925 		    diff * best_den < best_diff * den) {
926 			best_diff = diff;
927 			best_den = den;
928 			best_num = num;
929 		}
930 	}
931 	if (best_den == 0) {
932 		i->empty = 1;
933 		return -EINVAL;
934 	}
935 	t.min = div_down(best_num, best_den);
936 	t.openmin = !!(best_num % best_den);
937 
938 	best_num = best_den = best_diff = 0;
939 	for (k = 0; k < rats_count; ++k) {
940 		unsigned int num;
941 		unsigned int den = rats[k].den;
942 		unsigned int q = i->max;
943 		int diff;
944 		num = mul(q, den);
945 		if (num < rats[k].num_min)
946 			continue;
947 		if (num > rats[k].num_max)
948 			num = rats[k].num_max;
949 		else {
950 			unsigned int r;
951 			r = (num - rats[k].num_min) % rats[k].num_step;
952 			if (r != 0)
953 				num -= r;
954 		}
955 		diff = q * den - num;
956 		if (best_num == 0 ||
957 		    diff * best_den < best_diff * den) {
958 			best_diff = diff;
959 			best_den = den;
960 			best_num = num;
961 		}
962 	}
963 	if (best_den == 0) {
964 		i->empty = 1;
965 		return -EINVAL;
966 	}
967 	t.max = div_up(best_num, best_den);
968 	t.openmax = !!(best_num % best_den);
969 	t.integer = 0;
970 	err = snd_interval_refine(i, &t);
971 	if (err < 0)
972 		return err;
973 
974 	if (snd_interval_single(i)) {
975 		if (nump)
976 			*nump = best_num;
977 		if (denp)
978 			*denp = best_den;
979 	}
980 	return err;
981 }
982 
983 /**
984  * snd_interval_list - refine the interval value from the list
985  * @i: the interval value to refine
986  * @count: the number of elements in the list
987  * @list: the value list
988  * @mask: the bit-mask to evaluate
989  *
990  * Refines the interval value from the list.
991  * When mask is non-zero, only the elements corresponding to bit 1 are
992  * evaluated.
993  *
994  * Returns non-zero if the value is changed, zero if not changed.
995  */
996 int snd_interval_list(struct snd_interval *i, unsigned int count, unsigned int *list, unsigned int mask)
997 {
998         unsigned int k;
999 	struct snd_interval list_range;
1000 
1001 	if (!count) {
1002 		i->empty = 1;
1003 		return -EINVAL;
1004 	}
1005 	snd_interval_any(&list_range);
1006 	list_range.min = UINT_MAX;
1007 	list_range.max = 0;
1008         for (k = 0; k < count; k++) {
1009 		if (mask && !(mask & (1 << k)))
1010 			continue;
1011 		if (!snd_interval_test(i, list[k]))
1012 			continue;
1013 		list_range.min = min(list_range.min, list[k]);
1014 		list_range.max = max(list_range.max, list[k]);
1015         }
1016 	return snd_interval_refine(i, &list_range);
1017 }
1018 
1019 EXPORT_SYMBOL(snd_interval_list);
1020 
1021 static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
1022 {
1023 	unsigned int n;
1024 	int changed = 0;
1025 	n = (i->min - min) % step;
1026 	if (n != 0 || i->openmin) {
1027 		i->min += step - n;
1028 		changed = 1;
1029 	}
1030 	n = (i->max - min) % step;
1031 	if (n != 0 || i->openmax) {
1032 		i->max -= n;
1033 		changed = 1;
1034 	}
1035 	if (snd_interval_checkempty(i)) {
1036 		i->empty = 1;
1037 		return -EINVAL;
1038 	}
1039 	return changed;
1040 }
1041 
1042 /* Info constraints helpers */
1043 
1044 /**
1045  * snd_pcm_hw_rule_add - add the hw-constraint rule
1046  * @runtime: the pcm runtime instance
1047  * @cond: condition bits
1048  * @var: the variable to evaluate
1049  * @func: the evaluation function
1050  * @private: the private data pointer passed to function
1051  * @dep: the dependent variables
1052  *
1053  * Returns zero if successful, or a negative error code on failure.
1054  */
1055 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1056 			int var,
1057 			snd_pcm_hw_rule_func_t func, void *private,
1058 			int dep, ...)
1059 {
1060 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1061 	struct snd_pcm_hw_rule *c;
1062 	unsigned int k;
1063 	va_list args;
1064 	va_start(args, dep);
1065 	if (constrs->rules_num >= constrs->rules_all) {
1066 		struct snd_pcm_hw_rule *new;
1067 		unsigned int new_rules = constrs->rules_all + 16;
1068 		new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1069 		if (!new)
1070 			return -ENOMEM;
1071 		if (constrs->rules) {
1072 			memcpy(new, constrs->rules,
1073 			       constrs->rules_num * sizeof(*c));
1074 			kfree(constrs->rules);
1075 		}
1076 		constrs->rules = new;
1077 		constrs->rules_all = new_rules;
1078 	}
1079 	c = &constrs->rules[constrs->rules_num];
1080 	c->cond = cond;
1081 	c->func = func;
1082 	c->var = var;
1083 	c->private = private;
1084 	k = 0;
1085 	while (1) {
1086 		if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps)))
1087 			return -EINVAL;
1088 		c->deps[k++] = dep;
1089 		if (dep < 0)
1090 			break;
1091 		dep = va_arg(args, int);
1092 	}
1093 	constrs->rules_num++;
1094 	va_end(args);
1095 	return 0;
1096 }
1097 
1098 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1099 
1100 /**
1101  * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1102  * @runtime: PCM runtime instance
1103  * @var: hw_params variable to apply the mask
1104  * @mask: the bitmap mask
1105  *
1106  * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1107  */
1108 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1109 			       u_int32_t mask)
1110 {
1111 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1112 	struct snd_mask *maskp = constrs_mask(constrs, var);
1113 	*maskp->bits &= mask;
1114 	memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1115 	if (*maskp->bits == 0)
1116 		return -EINVAL;
1117 	return 0;
1118 }
1119 
1120 /**
1121  * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1122  * @runtime: PCM runtime instance
1123  * @var: hw_params variable to apply the mask
1124  * @mask: the 64bit bitmap mask
1125  *
1126  * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1127  */
1128 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1129 				 u_int64_t mask)
1130 {
1131 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1132 	struct snd_mask *maskp = constrs_mask(constrs, var);
1133 	maskp->bits[0] &= (u_int32_t)mask;
1134 	maskp->bits[1] &= (u_int32_t)(mask >> 32);
1135 	memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1136 	if (! maskp->bits[0] && ! maskp->bits[1])
1137 		return -EINVAL;
1138 	return 0;
1139 }
1140 
1141 /**
1142  * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1143  * @runtime: PCM runtime instance
1144  * @var: hw_params variable to apply the integer constraint
1145  *
1146  * Apply the constraint of integer to an interval parameter.
1147  */
1148 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1149 {
1150 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1151 	return snd_interval_setinteger(constrs_interval(constrs, var));
1152 }
1153 
1154 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1155 
1156 /**
1157  * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1158  * @runtime: PCM runtime instance
1159  * @var: hw_params variable to apply the range
1160  * @min: the minimal value
1161  * @max: the maximal value
1162  *
1163  * Apply the min/max range constraint to an interval parameter.
1164  */
1165 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1166 				 unsigned int min, unsigned int max)
1167 {
1168 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1169 	struct snd_interval t;
1170 	t.min = min;
1171 	t.max = max;
1172 	t.openmin = t.openmax = 0;
1173 	t.integer = 0;
1174 	return snd_interval_refine(constrs_interval(constrs, var), &t);
1175 }
1176 
1177 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1178 
1179 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1180 				struct snd_pcm_hw_rule *rule)
1181 {
1182 	struct snd_pcm_hw_constraint_list *list = rule->private;
1183 	return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1184 }
1185 
1186 
1187 /**
1188  * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1189  * @runtime: PCM runtime instance
1190  * @cond: condition bits
1191  * @var: hw_params variable to apply the list constraint
1192  * @l: list
1193  *
1194  * Apply the list of constraints to an interval parameter.
1195  */
1196 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1197 			       unsigned int cond,
1198 			       snd_pcm_hw_param_t var,
1199 			       struct snd_pcm_hw_constraint_list *l)
1200 {
1201 	return snd_pcm_hw_rule_add(runtime, cond, var,
1202 				   snd_pcm_hw_rule_list, l,
1203 				   var, -1);
1204 }
1205 
1206 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1207 
1208 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1209 				   struct snd_pcm_hw_rule *rule)
1210 {
1211 	struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1212 	unsigned int num = 0, den = 0;
1213 	int err;
1214 	err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1215 				  r->nrats, r->rats, &num, &den);
1216 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1217 		params->rate_num = num;
1218 		params->rate_den = den;
1219 	}
1220 	return err;
1221 }
1222 
1223 /**
1224  * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1225  * @runtime: PCM runtime instance
1226  * @cond: condition bits
1227  * @var: hw_params variable to apply the ratnums constraint
1228  * @r: struct snd_ratnums constriants
1229  */
1230 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1231 				  unsigned int cond,
1232 				  snd_pcm_hw_param_t var,
1233 				  struct snd_pcm_hw_constraint_ratnums *r)
1234 {
1235 	return snd_pcm_hw_rule_add(runtime, cond, var,
1236 				   snd_pcm_hw_rule_ratnums, r,
1237 				   var, -1);
1238 }
1239 
1240 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1241 
1242 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1243 				   struct snd_pcm_hw_rule *rule)
1244 {
1245 	struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1246 	unsigned int num = 0, den = 0;
1247 	int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1248 				  r->nrats, r->rats, &num, &den);
1249 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1250 		params->rate_num = num;
1251 		params->rate_den = den;
1252 	}
1253 	return err;
1254 }
1255 
1256 /**
1257  * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1258  * @runtime: PCM runtime instance
1259  * @cond: condition bits
1260  * @var: hw_params variable to apply the ratdens constraint
1261  * @r: struct snd_ratdens constriants
1262  */
1263 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1264 				  unsigned int cond,
1265 				  snd_pcm_hw_param_t var,
1266 				  struct snd_pcm_hw_constraint_ratdens *r)
1267 {
1268 	return snd_pcm_hw_rule_add(runtime, cond, var,
1269 				   snd_pcm_hw_rule_ratdens, r,
1270 				   var, -1);
1271 }
1272 
1273 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1274 
1275 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1276 				  struct snd_pcm_hw_rule *rule)
1277 {
1278 	unsigned int l = (unsigned long) rule->private;
1279 	int width = l & 0xffff;
1280 	unsigned int msbits = l >> 16;
1281 	struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1282 	if (snd_interval_single(i) && snd_interval_value(i) == width)
1283 		params->msbits = msbits;
1284 	return 0;
1285 }
1286 
1287 /**
1288  * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1289  * @runtime: PCM runtime instance
1290  * @cond: condition bits
1291  * @width: sample bits width
1292  * @msbits: msbits width
1293  */
1294 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1295 				 unsigned int cond,
1296 				 unsigned int width,
1297 				 unsigned int msbits)
1298 {
1299 	unsigned long l = (msbits << 16) | width;
1300 	return snd_pcm_hw_rule_add(runtime, cond, -1,
1301 				    snd_pcm_hw_rule_msbits,
1302 				    (void*) l,
1303 				    SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1304 }
1305 
1306 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1307 
1308 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1309 				struct snd_pcm_hw_rule *rule)
1310 {
1311 	unsigned long step = (unsigned long) rule->private;
1312 	return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1313 }
1314 
1315 /**
1316  * snd_pcm_hw_constraint_step - add a hw constraint step rule
1317  * @runtime: PCM runtime instance
1318  * @cond: condition bits
1319  * @var: hw_params variable to apply the step constraint
1320  * @step: step size
1321  */
1322 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1323 			       unsigned int cond,
1324 			       snd_pcm_hw_param_t var,
1325 			       unsigned long step)
1326 {
1327 	return snd_pcm_hw_rule_add(runtime, cond, var,
1328 				   snd_pcm_hw_rule_step, (void *) step,
1329 				   var, -1);
1330 }
1331 
1332 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1333 
1334 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1335 {
1336 	static unsigned int pow2_sizes[] = {
1337 		1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1338 		1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1339 		1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1340 		1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1341 	};
1342 	return snd_interval_list(hw_param_interval(params, rule->var),
1343 				 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1344 }
1345 
1346 /**
1347  * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1348  * @runtime: PCM runtime instance
1349  * @cond: condition bits
1350  * @var: hw_params variable to apply the power-of-2 constraint
1351  */
1352 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1353 			       unsigned int cond,
1354 			       snd_pcm_hw_param_t var)
1355 {
1356 	return snd_pcm_hw_rule_add(runtime, cond, var,
1357 				   snd_pcm_hw_rule_pow2, NULL,
1358 				   var, -1);
1359 }
1360 
1361 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1362 
1363 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1364 				  snd_pcm_hw_param_t var)
1365 {
1366 	if (hw_is_mask(var)) {
1367 		snd_mask_any(hw_param_mask(params, var));
1368 		params->cmask |= 1 << var;
1369 		params->rmask |= 1 << var;
1370 		return;
1371 	}
1372 	if (hw_is_interval(var)) {
1373 		snd_interval_any(hw_param_interval(params, var));
1374 		params->cmask |= 1 << var;
1375 		params->rmask |= 1 << var;
1376 		return;
1377 	}
1378 	snd_BUG();
1379 }
1380 
1381 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1382 {
1383 	unsigned int k;
1384 	memset(params, 0, sizeof(*params));
1385 	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1386 		_snd_pcm_hw_param_any(params, k);
1387 	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1388 		_snd_pcm_hw_param_any(params, k);
1389 	params->info = ~0U;
1390 }
1391 
1392 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1393 
1394 /**
1395  * snd_pcm_hw_param_value - return @params field @var value
1396  * @params: the hw_params instance
1397  * @var: parameter to retrieve
1398  * @dir: pointer to the direction (-1,0,1) or %NULL
1399  *
1400  * Return the value for field @var if it's fixed in configuration space
1401  * defined by @params. Return -%EINVAL otherwise.
1402  */
1403 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1404 			   snd_pcm_hw_param_t var, int *dir)
1405 {
1406 	if (hw_is_mask(var)) {
1407 		const struct snd_mask *mask = hw_param_mask_c(params, var);
1408 		if (!snd_mask_single(mask))
1409 			return -EINVAL;
1410 		if (dir)
1411 			*dir = 0;
1412 		return snd_mask_value(mask);
1413 	}
1414 	if (hw_is_interval(var)) {
1415 		const struct snd_interval *i = hw_param_interval_c(params, var);
1416 		if (!snd_interval_single(i))
1417 			return -EINVAL;
1418 		if (dir)
1419 			*dir = i->openmin;
1420 		return snd_interval_value(i);
1421 	}
1422 	return -EINVAL;
1423 }
1424 
1425 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1426 
1427 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1428 				snd_pcm_hw_param_t var)
1429 {
1430 	if (hw_is_mask(var)) {
1431 		snd_mask_none(hw_param_mask(params, var));
1432 		params->cmask |= 1 << var;
1433 		params->rmask |= 1 << var;
1434 	} else if (hw_is_interval(var)) {
1435 		snd_interval_none(hw_param_interval(params, var));
1436 		params->cmask |= 1 << var;
1437 		params->rmask |= 1 << var;
1438 	} else {
1439 		snd_BUG();
1440 	}
1441 }
1442 
1443 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1444 
1445 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1446 				   snd_pcm_hw_param_t var)
1447 {
1448 	int changed;
1449 	if (hw_is_mask(var))
1450 		changed = snd_mask_refine_first(hw_param_mask(params, var));
1451 	else if (hw_is_interval(var))
1452 		changed = snd_interval_refine_first(hw_param_interval(params, var));
1453 	else
1454 		return -EINVAL;
1455 	if (changed) {
1456 		params->cmask |= 1 << var;
1457 		params->rmask |= 1 << var;
1458 	}
1459 	return changed;
1460 }
1461 
1462 
1463 /**
1464  * snd_pcm_hw_param_first - refine config space and return minimum value
1465  * @pcm: PCM instance
1466  * @params: the hw_params instance
1467  * @var: parameter to retrieve
1468  * @dir: pointer to the direction (-1,0,1) or %NULL
1469  *
1470  * Inside configuration space defined by @params remove from @var all
1471  * values > minimum. Reduce configuration space accordingly.
1472  * Return the minimum.
1473  */
1474 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1475 			   struct snd_pcm_hw_params *params,
1476 			   snd_pcm_hw_param_t var, int *dir)
1477 {
1478 	int changed = _snd_pcm_hw_param_first(params, var);
1479 	if (changed < 0)
1480 		return changed;
1481 	if (params->rmask) {
1482 		int err = snd_pcm_hw_refine(pcm, params);
1483 		if (snd_BUG_ON(err < 0))
1484 			return err;
1485 	}
1486 	return snd_pcm_hw_param_value(params, var, dir);
1487 }
1488 
1489 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1490 
1491 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1492 				  snd_pcm_hw_param_t var)
1493 {
1494 	int changed;
1495 	if (hw_is_mask(var))
1496 		changed = snd_mask_refine_last(hw_param_mask(params, var));
1497 	else if (hw_is_interval(var))
1498 		changed = snd_interval_refine_last(hw_param_interval(params, var));
1499 	else
1500 		return -EINVAL;
1501 	if (changed) {
1502 		params->cmask |= 1 << var;
1503 		params->rmask |= 1 << var;
1504 	}
1505 	return changed;
1506 }
1507 
1508 
1509 /**
1510  * snd_pcm_hw_param_last - refine config space and return maximum value
1511  * @pcm: PCM instance
1512  * @params: the hw_params instance
1513  * @var: parameter to retrieve
1514  * @dir: pointer to the direction (-1,0,1) or %NULL
1515  *
1516  * Inside configuration space defined by @params remove from @var all
1517  * values < maximum. Reduce configuration space accordingly.
1518  * Return the maximum.
1519  */
1520 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1521 			  struct snd_pcm_hw_params *params,
1522 			  snd_pcm_hw_param_t var, int *dir)
1523 {
1524 	int changed = _snd_pcm_hw_param_last(params, var);
1525 	if (changed < 0)
1526 		return changed;
1527 	if (params->rmask) {
1528 		int err = snd_pcm_hw_refine(pcm, params);
1529 		if (snd_BUG_ON(err < 0))
1530 			return err;
1531 	}
1532 	return snd_pcm_hw_param_value(params, var, dir);
1533 }
1534 
1535 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1536 
1537 /**
1538  * snd_pcm_hw_param_choose - choose a configuration defined by @params
1539  * @pcm: PCM instance
1540  * @params: the hw_params instance
1541  *
1542  * Choose one configuration from configuration space defined by @params.
1543  * The configuration chosen is that obtained fixing in this order:
1544  * first access, first format, first subformat, min channels,
1545  * min rate, min period time, max buffer size, min tick time
1546  */
1547 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1548 			     struct snd_pcm_hw_params *params)
1549 {
1550 	static int vars[] = {
1551 		SNDRV_PCM_HW_PARAM_ACCESS,
1552 		SNDRV_PCM_HW_PARAM_FORMAT,
1553 		SNDRV_PCM_HW_PARAM_SUBFORMAT,
1554 		SNDRV_PCM_HW_PARAM_CHANNELS,
1555 		SNDRV_PCM_HW_PARAM_RATE,
1556 		SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1557 		SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1558 		SNDRV_PCM_HW_PARAM_TICK_TIME,
1559 		-1
1560 	};
1561 	int err, *v;
1562 
1563 	for (v = vars; *v != -1; v++) {
1564 		if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1565 			err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1566 		else
1567 			err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1568 		if (snd_BUG_ON(err < 0))
1569 			return err;
1570 	}
1571 	return 0;
1572 }
1573 
1574 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1575 				   void *arg)
1576 {
1577 	struct snd_pcm_runtime *runtime = substream->runtime;
1578 	unsigned long flags;
1579 	snd_pcm_stream_lock_irqsave(substream, flags);
1580 	if (snd_pcm_running(substream) &&
1581 	    snd_pcm_update_hw_ptr(substream) >= 0)
1582 		runtime->status->hw_ptr %= runtime->buffer_size;
1583 	else
1584 		runtime->status->hw_ptr = 0;
1585 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1586 	return 0;
1587 }
1588 
1589 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1590 					  void *arg)
1591 {
1592 	struct snd_pcm_channel_info *info = arg;
1593 	struct snd_pcm_runtime *runtime = substream->runtime;
1594 	int width;
1595 	if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1596 		info->offset = -1;
1597 		return 0;
1598 	}
1599 	width = snd_pcm_format_physical_width(runtime->format);
1600 	if (width < 0)
1601 		return width;
1602 	info->offset = 0;
1603 	switch (runtime->access) {
1604 	case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1605 	case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1606 		info->first = info->channel * width;
1607 		info->step = runtime->channels * width;
1608 		break;
1609 	case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1610 	case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1611 	{
1612 		size_t size = runtime->dma_bytes / runtime->channels;
1613 		info->first = info->channel * size * 8;
1614 		info->step = width;
1615 		break;
1616 	}
1617 	default:
1618 		snd_BUG();
1619 		break;
1620 	}
1621 	return 0;
1622 }
1623 
1624 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1625 				       void *arg)
1626 {
1627 	struct snd_pcm_hw_params *params = arg;
1628 	snd_pcm_format_t format;
1629 	int channels, width;
1630 
1631 	params->fifo_size = substream->runtime->hw.fifo_size;
1632 	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1633 		format = params_format(params);
1634 		channels = params_channels(params);
1635 		width = snd_pcm_format_physical_width(format);
1636 		params->fifo_size /= width * channels;
1637 	}
1638 	return 0;
1639 }
1640 
1641 /**
1642  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1643  * @substream: the pcm substream instance
1644  * @cmd: ioctl command
1645  * @arg: ioctl argument
1646  *
1647  * Processes the generic ioctl commands for PCM.
1648  * Can be passed as the ioctl callback for PCM ops.
1649  *
1650  * Returns zero if successful, or a negative error code on failure.
1651  */
1652 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1653 		      unsigned int cmd, void *arg)
1654 {
1655 	switch (cmd) {
1656 	case SNDRV_PCM_IOCTL1_INFO:
1657 		return 0;
1658 	case SNDRV_PCM_IOCTL1_RESET:
1659 		return snd_pcm_lib_ioctl_reset(substream, arg);
1660 	case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1661 		return snd_pcm_lib_ioctl_channel_info(substream, arg);
1662 	case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1663 		return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1664 	}
1665 	return -ENXIO;
1666 }
1667 
1668 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1669 
1670 /**
1671  * snd_pcm_period_elapsed - update the pcm status for the next period
1672  * @substream: the pcm substream instance
1673  *
1674  * This function is called from the interrupt handler when the
1675  * PCM has processed the period size.  It will update the current
1676  * pointer, wake up sleepers, etc.
1677  *
1678  * Even if more than one periods have elapsed since the last call, you
1679  * have to call this only once.
1680  */
1681 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1682 {
1683 	struct snd_pcm_runtime *runtime;
1684 	unsigned long flags;
1685 
1686 	if (PCM_RUNTIME_CHECK(substream))
1687 		return;
1688 	runtime = substream->runtime;
1689 
1690 	if (runtime->transfer_ack_begin)
1691 		runtime->transfer_ack_begin(substream);
1692 
1693 	snd_pcm_stream_lock_irqsave(substream, flags);
1694 	if (!snd_pcm_running(substream) ||
1695 	    snd_pcm_update_hw_ptr0(substream, 1) < 0)
1696 		goto _end;
1697 
1698 	if (substream->timer_running)
1699 		snd_timer_interrupt(substream->timer, 1);
1700  _end:
1701 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1702 	if (runtime->transfer_ack_end)
1703 		runtime->transfer_ack_end(substream);
1704 	kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1705 }
1706 
1707 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1708 
1709 /*
1710  * Wait until avail_min data becomes available
1711  * Returns a negative error code if any error occurs during operation.
1712  * The available space is stored on availp.  When err = 0 and avail = 0
1713  * on the capture stream, it indicates the stream is in DRAINING state.
1714  */
1715 static int wait_for_avail(struct snd_pcm_substream *substream,
1716 			      snd_pcm_uframes_t *availp)
1717 {
1718 	struct snd_pcm_runtime *runtime = substream->runtime;
1719 	int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1720 	wait_queue_t wait;
1721 	int err = 0;
1722 	snd_pcm_uframes_t avail = 0;
1723 	long tout;
1724 
1725 	init_waitqueue_entry(&wait, current);
1726 	add_wait_queue(&runtime->tsleep, &wait);
1727 	for (;;) {
1728 		if (signal_pending(current)) {
1729 			err = -ERESTARTSYS;
1730 			break;
1731 		}
1732 		set_current_state(TASK_INTERRUPTIBLE);
1733 		snd_pcm_stream_unlock_irq(substream);
1734 		tout = schedule_timeout(msecs_to_jiffies(10000));
1735 		snd_pcm_stream_lock_irq(substream);
1736 		switch (runtime->status->state) {
1737 		case SNDRV_PCM_STATE_SUSPENDED:
1738 			err = -ESTRPIPE;
1739 			goto _endloop;
1740 		case SNDRV_PCM_STATE_XRUN:
1741 			err = -EPIPE;
1742 			goto _endloop;
1743 		case SNDRV_PCM_STATE_DRAINING:
1744 			if (is_playback)
1745 				err = -EPIPE;
1746 			else
1747 				avail = 0; /* indicate draining */
1748 			goto _endloop;
1749 		case SNDRV_PCM_STATE_OPEN:
1750 		case SNDRV_PCM_STATE_SETUP:
1751 		case SNDRV_PCM_STATE_DISCONNECTED:
1752 			err = -EBADFD;
1753 			goto _endloop;
1754 		}
1755 		if (!tout) {
1756 			snd_printd("%s write error (DMA or IRQ trouble?)\n",
1757 				   is_playback ? "playback" : "capture");
1758 			err = -EIO;
1759 			break;
1760 		}
1761 		if (is_playback)
1762 			avail = snd_pcm_playback_avail(runtime);
1763 		else
1764 			avail = snd_pcm_capture_avail(runtime);
1765 		if (avail >= runtime->twake)
1766 			break;
1767 	}
1768  _endloop:
1769 	remove_wait_queue(&runtime->tsleep, &wait);
1770 	*availp = avail;
1771 	return err;
1772 }
1773 
1774 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1775 				      unsigned int hwoff,
1776 				      unsigned long data, unsigned int off,
1777 				      snd_pcm_uframes_t frames)
1778 {
1779 	struct snd_pcm_runtime *runtime = substream->runtime;
1780 	int err;
1781 	char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1782 	if (substream->ops->copy) {
1783 		if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1784 			return err;
1785 	} else {
1786 		char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1787 		if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1788 			return -EFAULT;
1789 	}
1790 	return 0;
1791 }
1792 
1793 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1794 			  unsigned long data, unsigned int off,
1795 			  snd_pcm_uframes_t size);
1796 
1797 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1798 					    unsigned long data,
1799 					    snd_pcm_uframes_t size,
1800 					    int nonblock,
1801 					    transfer_f transfer)
1802 {
1803 	struct snd_pcm_runtime *runtime = substream->runtime;
1804 	snd_pcm_uframes_t xfer = 0;
1805 	snd_pcm_uframes_t offset = 0;
1806 	int err = 0;
1807 
1808 	if (size == 0)
1809 		return 0;
1810 
1811 	snd_pcm_stream_lock_irq(substream);
1812 	switch (runtime->status->state) {
1813 	case SNDRV_PCM_STATE_PREPARED:
1814 	case SNDRV_PCM_STATE_RUNNING:
1815 	case SNDRV_PCM_STATE_PAUSED:
1816 		break;
1817 	case SNDRV_PCM_STATE_XRUN:
1818 		err = -EPIPE;
1819 		goto _end_unlock;
1820 	case SNDRV_PCM_STATE_SUSPENDED:
1821 		err = -ESTRPIPE;
1822 		goto _end_unlock;
1823 	default:
1824 		err = -EBADFD;
1825 		goto _end_unlock;
1826 	}
1827 
1828 	runtime->twake = runtime->control->avail_min ? : 1;
1829 	while (size > 0) {
1830 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1831 		snd_pcm_uframes_t avail;
1832 		snd_pcm_uframes_t cont;
1833 		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1834 			snd_pcm_update_hw_ptr(substream);
1835 		avail = snd_pcm_playback_avail(runtime);
1836 		if (!avail) {
1837 			if (nonblock) {
1838 				err = -EAGAIN;
1839 				goto _end_unlock;
1840 			}
1841 			runtime->twake = min_t(snd_pcm_uframes_t, size,
1842 					runtime->control->avail_min ? : 1);
1843 			err = wait_for_avail(substream, &avail);
1844 			if (err < 0)
1845 				goto _end_unlock;
1846 		}
1847 		frames = size > avail ? avail : size;
1848 		cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1849 		if (frames > cont)
1850 			frames = cont;
1851 		if (snd_BUG_ON(!frames)) {
1852 			runtime->twake = 0;
1853 			snd_pcm_stream_unlock_irq(substream);
1854 			return -EINVAL;
1855 		}
1856 		appl_ptr = runtime->control->appl_ptr;
1857 		appl_ofs = appl_ptr % runtime->buffer_size;
1858 		snd_pcm_stream_unlock_irq(substream);
1859 		err = transfer(substream, appl_ofs, data, offset, frames);
1860 		snd_pcm_stream_lock_irq(substream);
1861 		if (err < 0)
1862 			goto _end_unlock;
1863 		switch (runtime->status->state) {
1864 		case SNDRV_PCM_STATE_XRUN:
1865 			err = -EPIPE;
1866 			goto _end_unlock;
1867 		case SNDRV_PCM_STATE_SUSPENDED:
1868 			err = -ESTRPIPE;
1869 			goto _end_unlock;
1870 		default:
1871 			break;
1872 		}
1873 		appl_ptr += frames;
1874 		if (appl_ptr >= runtime->boundary)
1875 			appl_ptr -= runtime->boundary;
1876 		runtime->control->appl_ptr = appl_ptr;
1877 		if (substream->ops->ack)
1878 			substream->ops->ack(substream);
1879 
1880 		offset += frames;
1881 		size -= frames;
1882 		xfer += frames;
1883 		if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1884 		    snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1885 			err = snd_pcm_start(substream);
1886 			if (err < 0)
1887 				goto _end_unlock;
1888 		}
1889 	}
1890  _end_unlock:
1891 	runtime->twake = 0;
1892 	if (xfer > 0 && err >= 0)
1893 		snd_pcm_update_state(substream, runtime);
1894 	snd_pcm_stream_unlock_irq(substream);
1895 	return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
1896 }
1897 
1898 /* sanity-check for read/write methods */
1899 static int pcm_sanity_check(struct snd_pcm_substream *substream)
1900 {
1901 	struct snd_pcm_runtime *runtime;
1902 	if (PCM_RUNTIME_CHECK(substream))
1903 		return -ENXIO;
1904 	runtime = substream->runtime;
1905 	if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
1906 		return -EINVAL;
1907 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1908 		return -EBADFD;
1909 	return 0;
1910 }
1911 
1912 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
1913 {
1914 	struct snd_pcm_runtime *runtime;
1915 	int nonblock;
1916 	int err;
1917 
1918 	err = pcm_sanity_check(substream);
1919 	if (err < 0)
1920 		return err;
1921 	runtime = substream->runtime;
1922 	nonblock = !!(substream->f_flags & O_NONBLOCK);
1923 
1924 	if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
1925 	    runtime->channels > 1)
1926 		return -EINVAL;
1927 	return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
1928 				  snd_pcm_lib_write_transfer);
1929 }
1930 
1931 EXPORT_SYMBOL(snd_pcm_lib_write);
1932 
1933 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
1934 				       unsigned int hwoff,
1935 				       unsigned long data, unsigned int off,
1936 				       snd_pcm_uframes_t frames)
1937 {
1938 	struct snd_pcm_runtime *runtime = substream->runtime;
1939 	int err;
1940 	void __user **bufs = (void __user **)data;
1941 	int channels = runtime->channels;
1942 	int c;
1943 	if (substream->ops->copy) {
1944 		if (snd_BUG_ON(!substream->ops->silence))
1945 			return -EINVAL;
1946 		for (c = 0; c < channels; ++c, ++bufs) {
1947 			if (*bufs == NULL) {
1948 				if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
1949 					return err;
1950 			} else {
1951 				char __user *buf = *bufs + samples_to_bytes(runtime, off);
1952 				if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
1953 					return err;
1954 			}
1955 		}
1956 	} else {
1957 		/* default transfer behaviour */
1958 		size_t dma_csize = runtime->dma_bytes / channels;
1959 		for (c = 0; c < channels; ++c, ++bufs) {
1960 			char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
1961 			if (*bufs == NULL) {
1962 				snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
1963 			} else {
1964 				char __user *buf = *bufs + samples_to_bytes(runtime, off);
1965 				if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
1966 					return -EFAULT;
1967 			}
1968 		}
1969 	}
1970 	return 0;
1971 }
1972 
1973 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
1974 				     void __user **bufs,
1975 				     snd_pcm_uframes_t frames)
1976 {
1977 	struct snd_pcm_runtime *runtime;
1978 	int nonblock;
1979 	int err;
1980 
1981 	err = pcm_sanity_check(substream);
1982 	if (err < 0)
1983 		return err;
1984 	runtime = substream->runtime;
1985 	nonblock = !!(substream->f_flags & O_NONBLOCK);
1986 
1987 	if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
1988 		return -EINVAL;
1989 	return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
1990 				  nonblock, snd_pcm_lib_writev_transfer);
1991 }
1992 
1993 EXPORT_SYMBOL(snd_pcm_lib_writev);
1994 
1995 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
1996 				     unsigned int hwoff,
1997 				     unsigned long data, unsigned int off,
1998 				     snd_pcm_uframes_t frames)
1999 {
2000 	struct snd_pcm_runtime *runtime = substream->runtime;
2001 	int err;
2002 	char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2003 	if (substream->ops->copy) {
2004 		if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2005 			return err;
2006 	} else {
2007 		char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2008 		if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2009 			return -EFAULT;
2010 	}
2011 	return 0;
2012 }
2013 
2014 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2015 					   unsigned long data,
2016 					   snd_pcm_uframes_t size,
2017 					   int nonblock,
2018 					   transfer_f transfer)
2019 {
2020 	struct snd_pcm_runtime *runtime = substream->runtime;
2021 	snd_pcm_uframes_t xfer = 0;
2022 	snd_pcm_uframes_t offset = 0;
2023 	int err = 0;
2024 
2025 	if (size == 0)
2026 		return 0;
2027 
2028 	snd_pcm_stream_lock_irq(substream);
2029 	switch (runtime->status->state) {
2030 	case SNDRV_PCM_STATE_PREPARED:
2031 		if (size >= runtime->start_threshold) {
2032 			err = snd_pcm_start(substream);
2033 			if (err < 0)
2034 				goto _end_unlock;
2035 		}
2036 		break;
2037 	case SNDRV_PCM_STATE_DRAINING:
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 	while (size > 0) {
2054 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2055 		snd_pcm_uframes_t avail;
2056 		snd_pcm_uframes_t cont;
2057 		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2058 			snd_pcm_update_hw_ptr(substream);
2059 		avail = snd_pcm_capture_avail(runtime);
2060 		if (!avail) {
2061 			if (runtime->status->state ==
2062 			    SNDRV_PCM_STATE_DRAINING) {
2063 				snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2064 				goto _end_unlock;
2065 			}
2066 			if (nonblock) {
2067 				err = -EAGAIN;
2068 				goto _end_unlock;
2069 			}
2070 			runtime->twake = min_t(snd_pcm_uframes_t, size,
2071 					runtime->control->avail_min ? : 1);
2072 			err = wait_for_avail(substream, &avail);
2073 			if (err < 0)
2074 				goto _end_unlock;
2075 			if (!avail)
2076 				continue; /* draining */
2077 		}
2078 		frames = size > avail ? avail : size;
2079 		cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2080 		if (frames > cont)
2081 			frames = cont;
2082 		if (snd_BUG_ON(!frames)) {
2083 			runtime->twake = 0;
2084 			snd_pcm_stream_unlock_irq(substream);
2085 			return -EINVAL;
2086 		}
2087 		appl_ptr = runtime->control->appl_ptr;
2088 		appl_ofs = appl_ptr % runtime->buffer_size;
2089 		snd_pcm_stream_unlock_irq(substream);
2090 		err = transfer(substream, appl_ofs, data, offset, frames);
2091 		snd_pcm_stream_lock_irq(substream);
2092 		if (err < 0)
2093 			goto _end_unlock;
2094 		switch (runtime->status->state) {
2095 		case SNDRV_PCM_STATE_XRUN:
2096 			err = -EPIPE;
2097 			goto _end_unlock;
2098 		case SNDRV_PCM_STATE_SUSPENDED:
2099 			err = -ESTRPIPE;
2100 			goto _end_unlock;
2101 		default:
2102 			break;
2103 		}
2104 		appl_ptr += frames;
2105 		if (appl_ptr >= runtime->boundary)
2106 			appl_ptr -= runtime->boundary;
2107 		runtime->control->appl_ptr = appl_ptr;
2108 		if (substream->ops->ack)
2109 			substream->ops->ack(substream);
2110 
2111 		offset += frames;
2112 		size -= frames;
2113 		xfer += frames;
2114 	}
2115  _end_unlock:
2116 	runtime->twake = 0;
2117 	if (xfer > 0 && err >= 0)
2118 		snd_pcm_update_state(substream, runtime);
2119 	snd_pcm_stream_unlock_irq(substream);
2120 	return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2121 }
2122 
2123 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2124 {
2125 	struct snd_pcm_runtime *runtime;
2126 	int nonblock;
2127 	int err;
2128 
2129 	err = pcm_sanity_check(substream);
2130 	if (err < 0)
2131 		return err;
2132 	runtime = substream->runtime;
2133 	nonblock = !!(substream->f_flags & O_NONBLOCK);
2134 	if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2135 		return -EINVAL;
2136 	return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2137 }
2138 
2139 EXPORT_SYMBOL(snd_pcm_lib_read);
2140 
2141 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2142 				      unsigned int hwoff,
2143 				      unsigned long data, unsigned int off,
2144 				      snd_pcm_uframes_t frames)
2145 {
2146 	struct snd_pcm_runtime *runtime = substream->runtime;
2147 	int err;
2148 	void __user **bufs = (void __user **)data;
2149 	int channels = runtime->channels;
2150 	int c;
2151 	if (substream->ops->copy) {
2152 		for (c = 0; c < channels; ++c, ++bufs) {
2153 			char __user *buf;
2154 			if (*bufs == NULL)
2155 				continue;
2156 			buf = *bufs + samples_to_bytes(runtime, off);
2157 			if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2158 				return err;
2159 		}
2160 	} else {
2161 		snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2162 		for (c = 0; c < channels; ++c, ++bufs) {
2163 			char *hwbuf;
2164 			char __user *buf;
2165 			if (*bufs == NULL)
2166 				continue;
2167 
2168 			hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2169 			buf = *bufs + samples_to_bytes(runtime, off);
2170 			if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2171 				return -EFAULT;
2172 		}
2173 	}
2174 	return 0;
2175 }
2176 
2177 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2178 				    void __user **bufs,
2179 				    snd_pcm_uframes_t frames)
2180 {
2181 	struct snd_pcm_runtime *runtime;
2182 	int nonblock;
2183 	int err;
2184 
2185 	err = pcm_sanity_check(substream);
2186 	if (err < 0)
2187 		return err;
2188 	runtime = substream->runtime;
2189 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2190 		return -EBADFD;
2191 
2192 	nonblock = !!(substream->f_flags & O_NONBLOCK);
2193 	if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2194 		return -EINVAL;
2195 	return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2196 }
2197 
2198 EXPORT_SYMBOL(snd_pcm_lib_readv);
2199