xref: /linux/sound/core/pcm_lib.c (revision cb299ba8b5ef2239429484072fea394cd7581bd7)
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 			/* check for double acknowledged interrupts */
338 			hdelta = jiffies - runtime->hw_ptr_jiffies;
339 			if (hdelta > runtime->hw_ptr_buffer_jiffies/2) {
340 				hw_base += runtime->buffer_size;
341 				if (hw_base >= runtime->boundary)
342 					hw_base = 0;
343 				new_hw_ptr = hw_base + pos;
344 				goto __delta;
345 			}
346 		}
347 	}
348 	/* new_hw_ptr might be lower than old_hw_ptr in case when */
349 	/* pointer crosses the end of the ring buffer */
350 	if (new_hw_ptr < old_hw_ptr) {
351 		hw_base += runtime->buffer_size;
352 		if (hw_base >= runtime->boundary)
353 			hw_base = 0;
354 		new_hw_ptr = hw_base + pos;
355 	}
356       __delta:
357 	delta = new_hw_ptr - old_hw_ptr;
358 	if (delta < 0)
359 		delta += runtime->boundary;
360 	if (xrun_debug(substream, in_interrupt ?
361 			XRUN_DEBUG_PERIODUPDATE : XRUN_DEBUG_HWPTRUPDATE)) {
362 		char name[16];
363 		pcm_debug_name(substream, name, sizeof(name));
364 		snd_printd("%s_update: %s: pos=%u/%u/%u, "
365 			   "hwptr=%ld/%ld/%ld/%ld\n",
366 			   in_interrupt ? "period" : "hwptr",
367 			   name,
368 			   (unsigned int)pos,
369 			   (unsigned int)runtime->period_size,
370 			   (unsigned int)runtime->buffer_size,
371 			   (unsigned long)delta,
372 			   (unsigned long)old_hw_ptr,
373 			   (unsigned long)new_hw_ptr,
374 			   (unsigned long)runtime->hw_ptr_base);
375 	}
376 	/* something must be really wrong */
377 	if (delta >= runtime->buffer_size + runtime->period_size) {
378 		hw_ptr_error(substream,
379 			       "Unexpected hw_pointer value %s"
380 			       "(stream=%i, pos=%ld, new_hw_ptr=%ld, "
381 			       "old_hw_ptr=%ld)\n",
382 				     in_interrupt ? "[Q] " : "[P]",
383 				     substream->stream, (long)pos,
384 				     (long)new_hw_ptr, (long)old_hw_ptr);
385 		return 0;
386 	}
387 
388 	/* Do jiffies check only in xrun_debug mode */
389 	if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
390 		goto no_jiffies_check;
391 
392 	/* Skip the jiffies check for hardwares with BATCH flag.
393 	 * Such hardware usually just increases the position at each IRQ,
394 	 * thus it can't give any strange position.
395 	 */
396 	if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
397 		goto no_jiffies_check;
398 	hdelta = delta;
399 	if (hdelta < runtime->delay)
400 		goto no_jiffies_check;
401 	hdelta -= runtime->delay;
402 	jdelta = jiffies - runtime->hw_ptr_jiffies;
403 	if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
404 		delta = jdelta /
405 			(((runtime->period_size * HZ) / runtime->rate)
406 								+ HZ/100);
407 		/* move new_hw_ptr according jiffies not pos variable */
408 		new_hw_ptr = old_hw_ptr;
409 		hw_base = delta;
410 		/* use loop to avoid checks for delta overflows */
411 		/* the delta value is small or zero in most cases */
412 		while (delta > 0) {
413 			new_hw_ptr += runtime->period_size;
414 			if (new_hw_ptr >= runtime->boundary)
415 				new_hw_ptr -= runtime->boundary;
416 			delta--;
417 		}
418 		/* align hw_base to buffer_size */
419 		hw_ptr_error(substream,
420 			     "hw_ptr skipping! %s"
421 			     "(pos=%ld, delta=%ld, period=%ld, "
422 			     "jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
423 			     in_interrupt ? "[Q] " : "",
424 			     (long)pos, (long)hdelta,
425 			     (long)runtime->period_size, jdelta,
426 			     ((hdelta * HZ) / runtime->rate), hw_base,
427 			     (unsigned long)old_hw_ptr,
428 			     (unsigned long)new_hw_ptr);
429 		/* reset values to proper state */
430 		delta = 0;
431 		hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
432 	}
433  no_jiffies_check:
434 	if (delta > runtime->period_size + runtime->period_size / 2) {
435 		hw_ptr_error(substream,
436 			     "Lost interrupts? %s"
437 			     "(stream=%i, delta=%ld, new_hw_ptr=%ld, "
438 			     "old_hw_ptr=%ld)\n",
439 			     in_interrupt ? "[Q] " : "",
440 			     substream->stream, (long)delta,
441 			     (long)new_hw_ptr,
442 			     (long)old_hw_ptr);
443 	}
444 
445 	if (runtime->status->hw_ptr == new_hw_ptr)
446 		return 0;
447 
448 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
449 	    runtime->silence_size > 0)
450 		snd_pcm_playback_silence(substream, new_hw_ptr);
451 
452 	if (in_interrupt) {
453 		delta = new_hw_ptr - runtime->hw_ptr_interrupt;
454 		if (delta < 0)
455 			delta += runtime->boundary;
456 		delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
457 		runtime->hw_ptr_interrupt += delta;
458 		if (runtime->hw_ptr_interrupt >= runtime->boundary)
459 			runtime->hw_ptr_interrupt -= runtime->boundary;
460 	}
461 	runtime->hw_ptr_base = hw_base;
462 	runtime->status->hw_ptr = new_hw_ptr;
463 	runtime->hw_ptr_jiffies = jiffies;
464 	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
465 		snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
466 
467 	return snd_pcm_update_state(substream, runtime);
468 }
469 
470 /* CAUTION: call it with irq disabled */
471 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
472 {
473 	return snd_pcm_update_hw_ptr0(substream, 0);
474 }
475 
476 /**
477  * snd_pcm_set_ops - set the PCM operators
478  * @pcm: the pcm instance
479  * @direction: stream direction, SNDRV_PCM_STREAM_XXX
480  * @ops: the operator table
481  *
482  * Sets the given PCM operators to the pcm instance.
483  */
484 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction, struct snd_pcm_ops *ops)
485 {
486 	struct snd_pcm_str *stream = &pcm->streams[direction];
487 	struct snd_pcm_substream *substream;
488 
489 	for (substream = stream->substream; substream != NULL; substream = substream->next)
490 		substream->ops = ops;
491 }
492 
493 EXPORT_SYMBOL(snd_pcm_set_ops);
494 
495 /**
496  * snd_pcm_sync - set the PCM sync id
497  * @substream: the pcm substream
498  *
499  * Sets the PCM sync identifier for the card.
500  */
501 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
502 {
503 	struct snd_pcm_runtime *runtime = substream->runtime;
504 
505 	runtime->sync.id32[0] = substream->pcm->card->number;
506 	runtime->sync.id32[1] = -1;
507 	runtime->sync.id32[2] = -1;
508 	runtime->sync.id32[3] = -1;
509 }
510 
511 EXPORT_SYMBOL(snd_pcm_set_sync);
512 
513 /*
514  *  Standard ioctl routine
515  */
516 
517 static inline unsigned int div32(unsigned int a, unsigned int b,
518 				 unsigned int *r)
519 {
520 	if (b == 0) {
521 		*r = 0;
522 		return UINT_MAX;
523 	}
524 	*r = a % b;
525 	return a / b;
526 }
527 
528 static inline unsigned int div_down(unsigned int a, unsigned int b)
529 {
530 	if (b == 0)
531 		return UINT_MAX;
532 	return a / b;
533 }
534 
535 static inline unsigned int div_up(unsigned int a, unsigned int b)
536 {
537 	unsigned int r;
538 	unsigned int q;
539 	if (b == 0)
540 		return UINT_MAX;
541 	q = div32(a, b, &r);
542 	if (r)
543 		++q;
544 	return q;
545 }
546 
547 static inline unsigned int mul(unsigned int a, unsigned int b)
548 {
549 	if (a == 0)
550 		return 0;
551 	if (div_down(UINT_MAX, a) < b)
552 		return UINT_MAX;
553 	return a * b;
554 }
555 
556 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
557 				    unsigned int c, unsigned int *r)
558 {
559 	u_int64_t n = (u_int64_t) a * b;
560 	if (c == 0) {
561 		snd_BUG_ON(!n);
562 		*r = 0;
563 		return UINT_MAX;
564 	}
565 	n = div_u64_rem(n, c, r);
566 	if (n >= UINT_MAX) {
567 		*r = 0;
568 		return UINT_MAX;
569 	}
570 	return n;
571 }
572 
573 /**
574  * snd_interval_refine - refine the interval value of configurator
575  * @i: the interval value to refine
576  * @v: the interval value to refer to
577  *
578  * Refines the interval value with the reference value.
579  * The interval is changed to the range satisfying both intervals.
580  * The interval status (min, max, integer, etc.) are evaluated.
581  *
582  * Returns non-zero if the value is changed, zero if not changed.
583  */
584 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
585 {
586 	int changed = 0;
587 	if (snd_BUG_ON(snd_interval_empty(i)))
588 		return -EINVAL;
589 	if (i->min < v->min) {
590 		i->min = v->min;
591 		i->openmin = v->openmin;
592 		changed = 1;
593 	} else if (i->min == v->min && !i->openmin && v->openmin) {
594 		i->openmin = 1;
595 		changed = 1;
596 	}
597 	if (i->max > v->max) {
598 		i->max = v->max;
599 		i->openmax = v->openmax;
600 		changed = 1;
601 	} else if (i->max == v->max && !i->openmax && v->openmax) {
602 		i->openmax = 1;
603 		changed = 1;
604 	}
605 	if (!i->integer && v->integer) {
606 		i->integer = 1;
607 		changed = 1;
608 	}
609 	if (i->integer) {
610 		if (i->openmin) {
611 			i->min++;
612 			i->openmin = 0;
613 		}
614 		if (i->openmax) {
615 			i->max--;
616 			i->openmax = 0;
617 		}
618 	} else if (!i->openmin && !i->openmax && i->min == i->max)
619 		i->integer = 1;
620 	if (snd_interval_checkempty(i)) {
621 		snd_interval_none(i);
622 		return -EINVAL;
623 	}
624 	return changed;
625 }
626 
627 EXPORT_SYMBOL(snd_interval_refine);
628 
629 static int snd_interval_refine_first(struct snd_interval *i)
630 {
631 	if (snd_BUG_ON(snd_interval_empty(i)))
632 		return -EINVAL;
633 	if (snd_interval_single(i))
634 		return 0;
635 	i->max = i->min;
636 	i->openmax = i->openmin;
637 	if (i->openmax)
638 		i->max++;
639 	return 1;
640 }
641 
642 static int snd_interval_refine_last(struct snd_interval *i)
643 {
644 	if (snd_BUG_ON(snd_interval_empty(i)))
645 		return -EINVAL;
646 	if (snd_interval_single(i))
647 		return 0;
648 	i->min = i->max;
649 	i->openmin = i->openmax;
650 	if (i->openmin)
651 		i->min--;
652 	return 1;
653 }
654 
655 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
656 {
657 	if (a->empty || b->empty) {
658 		snd_interval_none(c);
659 		return;
660 	}
661 	c->empty = 0;
662 	c->min = mul(a->min, b->min);
663 	c->openmin = (a->openmin || b->openmin);
664 	c->max = mul(a->max,  b->max);
665 	c->openmax = (a->openmax || b->openmax);
666 	c->integer = (a->integer && b->integer);
667 }
668 
669 /**
670  * snd_interval_div - refine the interval value with division
671  * @a: dividend
672  * @b: divisor
673  * @c: quotient
674  *
675  * c = a / b
676  *
677  * Returns non-zero if the value is changed, zero if not changed.
678  */
679 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
680 {
681 	unsigned int r;
682 	if (a->empty || b->empty) {
683 		snd_interval_none(c);
684 		return;
685 	}
686 	c->empty = 0;
687 	c->min = div32(a->min, b->max, &r);
688 	c->openmin = (r || a->openmin || b->openmax);
689 	if (b->min > 0) {
690 		c->max = div32(a->max, b->min, &r);
691 		if (r) {
692 			c->max++;
693 			c->openmax = 1;
694 		} else
695 			c->openmax = (a->openmax || b->openmin);
696 	} else {
697 		c->max = UINT_MAX;
698 		c->openmax = 0;
699 	}
700 	c->integer = 0;
701 }
702 
703 /**
704  * snd_interval_muldivk - refine the interval value
705  * @a: dividend 1
706  * @b: dividend 2
707  * @k: divisor (as integer)
708  * @c: result
709   *
710  * c = a * b / k
711  *
712  * Returns non-zero if the value is changed, zero if not changed.
713  */
714 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
715 		      unsigned int k, struct snd_interval *c)
716 {
717 	unsigned int r;
718 	if (a->empty || b->empty) {
719 		snd_interval_none(c);
720 		return;
721 	}
722 	c->empty = 0;
723 	c->min = muldiv32(a->min, b->min, k, &r);
724 	c->openmin = (r || a->openmin || b->openmin);
725 	c->max = muldiv32(a->max, b->max, k, &r);
726 	if (r) {
727 		c->max++;
728 		c->openmax = 1;
729 	} else
730 		c->openmax = (a->openmax || b->openmax);
731 	c->integer = 0;
732 }
733 
734 /**
735  * snd_interval_mulkdiv - refine the interval value
736  * @a: dividend 1
737  * @k: dividend 2 (as integer)
738  * @b: divisor
739  * @c: result
740  *
741  * c = a * k / b
742  *
743  * Returns non-zero if the value is changed, zero if not changed.
744  */
745 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
746 		      const struct snd_interval *b, struct snd_interval *c)
747 {
748 	unsigned int r;
749 	if (a->empty || b->empty) {
750 		snd_interval_none(c);
751 		return;
752 	}
753 	c->empty = 0;
754 	c->min = muldiv32(a->min, k, b->max, &r);
755 	c->openmin = (r || a->openmin || b->openmax);
756 	if (b->min > 0) {
757 		c->max = muldiv32(a->max, k, b->min, &r);
758 		if (r) {
759 			c->max++;
760 			c->openmax = 1;
761 		} else
762 			c->openmax = (a->openmax || b->openmin);
763 	} else {
764 		c->max = UINT_MAX;
765 		c->openmax = 0;
766 	}
767 	c->integer = 0;
768 }
769 
770 /* ---- */
771 
772 
773 /**
774  * snd_interval_ratnum - refine the interval value
775  * @i: interval to refine
776  * @rats_count: number of ratnum_t
777  * @rats: ratnum_t array
778  * @nump: pointer to store the resultant numerator
779  * @denp: pointer to store the resultant denominator
780  *
781  * Returns non-zero if the value is changed, zero if not changed.
782  */
783 int snd_interval_ratnum(struct snd_interval *i,
784 			unsigned int rats_count, struct snd_ratnum *rats,
785 			unsigned int *nump, unsigned int *denp)
786 {
787 	unsigned int best_num, best_den;
788 	int best_diff;
789 	unsigned int k;
790 	struct snd_interval t;
791 	int err;
792 	unsigned int result_num, result_den;
793 	int result_diff;
794 
795 	best_num = best_den = best_diff = 0;
796 	for (k = 0; k < rats_count; ++k) {
797 		unsigned int num = rats[k].num;
798 		unsigned int den;
799 		unsigned int q = i->min;
800 		int diff;
801 		if (q == 0)
802 			q = 1;
803 		den = div_up(num, q);
804 		if (den < rats[k].den_min)
805 			continue;
806 		if (den > rats[k].den_max)
807 			den = rats[k].den_max;
808 		else {
809 			unsigned int r;
810 			r = (den - rats[k].den_min) % rats[k].den_step;
811 			if (r != 0)
812 				den -= r;
813 		}
814 		diff = num - q * den;
815 		if (diff < 0)
816 			diff = -diff;
817 		if (best_num == 0 ||
818 		    diff * best_den < best_diff * den) {
819 			best_diff = diff;
820 			best_den = den;
821 			best_num = num;
822 		}
823 	}
824 	if (best_den == 0) {
825 		i->empty = 1;
826 		return -EINVAL;
827 	}
828 	t.min = div_down(best_num, best_den);
829 	t.openmin = !!(best_num % best_den);
830 
831 	result_num = best_num;
832 	result_diff = best_diff;
833 	result_den = best_den;
834 	best_num = best_den = best_diff = 0;
835 	for (k = 0; k < rats_count; ++k) {
836 		unsigned int num = rats[k].num;
837 		unsigned int den;
838 		unsigned int q = i->max;
839 		int diff;
840 		if (q == 0) {
841 			i->empty = 1;
842 			return -EINVAL;
843 		}
844 		den = div_down(num, q);
845 		if (den > rats[k].den_max)
846 			continue;
847 		if (den < rats[k].den_min)
848 			den = rats[k].den_min;
849 		else {
850 			unsigned int r;
851 			r = (den - rats[k].den_min) % rats[k].den_step;
852 			if (r != 0)
853 				den += rats[k].den_step - r;
854 		}
855 		diff = q * den - num;
856 		if (diff < 0)
857 			diff = -diff;
858 		if (best_num == 0 ||
859 		    diff * best_den < best_diff * den) {
860 			best_diff = diff;
861 			best_den = den;
862 			best_num = num;
863 		}
864 	}
865 	if (best_den == 0) {
866 		i->empty = 1;
867 		return -EINVAL;
868 	}
869 	t.max = div_up(best_num, best_den);
870 	t.openmax = !!(best_num % best_den);
871 	t.integer = 0;
872 	err = snd_interval_refine(i, &t);
873 	if (err < 0)
874 		return err;
875 
876 	if (snd_interval_single(i)) {
877 		if (best_diff * result_den < result_diff * best_den) {
878 			result_num = best_num;
879 			result_den = best_den;
880 		}
881 		if (nump)
882 			*nump = result_num;
883 		if (denp)
884 			*denp = result_den;
885 	}
886 	return err;
887 }
888 
889 EXPORT_SYMBOL(snd_interval_ratnum);
890 
891 /**
892  * snd_interval_ratden - refine the interval value
893  * @i: interval to refine
894  * @rats_count: number of struct ratden
895  * @rats: struct ratden array
896  * @nump: pointer to store the resultant numerator
897  * @denp: pointer to store the resultant denominator
898  *
899  * Returns non-zero if the value is changed, zero if not changed.
900  */
901 static int snd_interval_ratden(struct snd_interval *i,
902 			       unsigned int rats_count, struct snd_ratden *rats,
903 			       unsigned int *nump, unsigned int *denp)
904 {
905 	unsigned int best_num, best_diff, best_den;
906 	unsigned int k;
907 	struct snd_interval t;
908 	int err;
909 
910 	best_num = best_den = best_diff = 0;
911 	for (k = 0; k < rats_count; ++k) {
912 		unsigned int num;
913 		unsigned int den = rats[k].den;
914 		unsigned int q = i->min;
915 		int diff;
916 		num = mul(q, den);
917 		if (num > rats[k].num_max)
918 			continue;
919 		if (num < rats[k].num_min)
920 			num = rats[k].num_max;
921 		else {
922 			unsigned int r;
923 			r = (num - rats[k].num_min) % rats[k].num_step;
924 			if (r != 0)
925 				num += rats[k].num_step - r;
926 		}
927 		diff = num - q * den;
928 		if (best_num == 0 ||
929 		    diff * best_den < best_diff * den) {
930 			best_diff = diff;
931 			best_den = den;
932 			best_num = num;
933 		}
934 	}
935 	if (best_den == 0) {
936 		i->empty = 1;
937 		return -EINVAL;
938 	}
939 	t.min = div_down(best_num, best_den);
940 	t.openmin = !!(best_num % best_den);
941 
942 	best_num = best_den = best_diff = 0;
943 	for (k = 0; k < rats_count; ++k) {
944 		unsigned int num;
945 		unsigned int den = rats[k].den;
946 		unsigned int q = i->max;
947 		int diff;
948 		num = mul(q, den);
949 		if (num < rats[k].num_min)
950 			continue;
951 		if (num > rats[k].num_max)
952 			num = rats[k].num_max;
953 		else {
954 			unsigned int r;
955 			r = (num - rats[k].num_min) % rats[k].num_step;
956 			if (r != 0)
957 				num -= r;
958 		}
959 		diff = q * den - num;
960 		if (best_num == 0 ||
961 		    diff * best_den < best_diff * den) {
962 			best_diff = diff;
963 			best_den = den;
964 			best_num = num;
965 		}
966 	}
967 	if (best_den == 0) {
968 		i->empty = 1;
969 		return -EINVAL;
970 	}
971 	t.max = div_up(best_num, best_den);
972 	t.openmax = !!(best_num % best_den);
973 	t.integer = 0;
974 	err = snd_interval_refine(i, &t);
975 	if (err < 0)
976 		return err;
977 
978 	if (snd_interval_single(i)) {
979 		if (nump)
980 			*nump = best_num;
981 		if (denp)
982 			*denp = best_den;
983 	}
984 	return err;
985 }
986 
987 /**
988  * snd_interval_list - refine the interval value from the list
989  * @i: the interval value to refine
990  * @count: the number of elements in the list
991  * @list: the value list
992  * @mask: the bit-mask to evaluate
993  *
994  * Refines the interval value from the list.
995  * When mask is non-zero, only the elements corresponding to bit 1 are
996  * evaluated.
997  *
998  * Returns non-zero if the value is changed, zero if not changed.
999  */
1000 int snd_interval_list(struct snd_interval *i, unsigned int count, unsigned int *list, unsigned int mask)
1001 {
1002         unsigned int k;
1003 	struct snd_interval list_range;
1004 
1005 	if (!count) {
1006 		i->empty = 1;
1007 		return -EINVAL;
1008 	}
1009 	snd_interval_any(&list_range);
1010 	list_range.min = UINT_MAX;
1011 	list_range.max = 0;
1012         for (k = 0; k < count; k++) {
1013 		if (mask && !(mask & (1 << k)))
1014 			continue;
1015 		if (!snd_interval_test(i, list[k]))
1016 			continue;
1017 		list_range.min = min(list_range.min, list[k]);
1018 		list_range.max = max(list_range.max, list[k]);
1019         }
1020 	return snd_interval_refine(i, &list_range);
1021 }
1022 
1023 EXPORT_SYMBOL(snd_interval_list);
1024 
1025 static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
1026 {
1027 	unsigned int n;
1028 	int changed = 0;
1029 	n = (i->min - min) % step;
1030 	if (n != 0 || i->openmin) {
1031 		i->min += step - n;
1032 		changed = 1;
1033 	}
1034 	n = (i->max - min) % step;
1035 	if (n != 0 || i->openmax) {
1036 		i->max -= n;
1037 		changed = 1;
1038 	}
1039 	if (snd_interval_checkempty(i)) {
1040 		i->empty = 1;
1041 		return -EINVAL;
1042 	}
1043 	return changed;
1044 }
1045 
1046 /* Info constraints helpers */
1047 
1048 /**
1049  * snd_pcm_hw_rule_add - add the hw-constraint rule
1050  * @runtime: the pcm runtime instance
1051  * @cond: condition bits
1052  * @var: the variable to evaluate
1053  * @func: the evaluation function
1054  * @private: the private data pointer passed to function
1055  * @dep: the dependent variables
1056  *
1057  * Returns zero if successful, or a negative error code on failure.
1058  */
1059 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1060 			int var,
1061 			snd_pcm_hw_rule_func_t func, void *private,
1062 			int dep, ...)
1063 {
1064 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1065 	struct snd_pcm_hw_rule *c;
1066 	unsigned int k;
1067 	va_list args;
1068 	va_start(args, dep);
1069 	if (constrs->rules_num >= constrs->rules_all) {
1070 		struct snd_pcm_hw_rule *new;
1071 		unsigned int new_rules = constrs->rules_all + 16;
1072 		new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1073 		if (!new)
1074 			return -ENOMEM;
1075 		if (constrs->rules) {
1076 			memcpy(new, constrs->rules,
1077 			       constrs->rules_num * sizeof(*c));
1078 			kfree(constrs->rules);
1079 		}
1080 		constrs->rules = new;
1081 		constrs->rules_all = new_rules;
1082 	}
1083 	c = &constrs->rules[constrs->rules_num];
1084 	c->cond = cond;
1085 	c->func = func;
1086 	c->var = var;
1087 	c->private = private;
1088 	k = 0;
1089 	while (1) {
1090 		if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps)))
1091 			return -EINVAL;
1092 		c->deps[k++] = dep;
1093 		if (dep < 0)
1094 			break;
1095 		dep = va_arg(args, int);
1096 	}
1097 	constrs->rules_num++;
1098 	va_end(args);
1099 	return 0;
1100 }
1101 
1102 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1103 
1104 /**
1105  * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1106  * @runtime: PCM runtime instance
1107  * @var: hw_params variable to apply the mask
1108  * @mask: the bitmap mask
1109  *
1110  * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1111  */
1112 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1113 			       u_int32_t mask)
1114 {
1115 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1116 	struct snd_mask *maskp = constrs_mask(constrs, var);
1117 	*maskp->bits &= mask;
1118 	memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1119 	if (*maskp->bits == 0)
1120 		return -EINVAL;
1121 	return 0;
1122 }
1123 
1124 /**
1125  * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1126  * @runtime: PCM runtime instance
1127  * @var: hw_params variable to apply the mask
1128  * @mask: the 64bit bitmap mask
1129  *
1130  * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1131  */
1132 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1133 				 u_int64_t mask)
1134 {
1135 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1136 	struct snd_mask *maskp = constrs_mask(constrs, var);
1137 	maskp->bits[0] &= (u_int32_t)mask;
1138 	maskp->bits[1] &= (u_int32_t)(mask >> 32);
1139 	memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1140 	if (! maskp->bits[0] && ! maskp->bits[1])
1141 		return -EINVAL;
1142 	return 0;
1143 }
1144 
1145 /**
1146  * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1147  * @runtime: PCM runtime instance
1148  * @var: hw_params variable to apply the integer constraint
1149  *
1150  * Apply the constraint of integer to an interval parameter.
1151  */
1152 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1153 {
1154 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1155 	return snd_interval_setinteger(constrs_interval(constrs, var));
1156 }
1157 
1158 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1159 
1160 /**
1161  * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1162  * @runtime: PCM runtime instance
1163  * @var: hw_params variable to apply the range
1164  * @min: the minimal value
1165  * @max: the maximal value
1166  *
1167  * Apply the min/max range constraint to an interval parameter.
1168  */
1169 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1170 				 unsigned int min, unsigned int max)
1171 {
1172 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1173 	struct snd_interval t;
1174 	t.min = min;
1175 	t.max = max;
1176 	t.openmin = t.openmax = 0;
1177 	t.integer = 0;
1178 	return snd_interval_refine(constrs_interval(constrs, var), &t);
1179 }
1180 
1181 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1182 
1183 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1184 				struct snd_pcm_hw_rule *rule)
1185 {
1186 	struct snd_pcm_hw_constraint_list *list = rule->private;
1187 	return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1188 }
1189 
1190 
1191 /**
1192  * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1193  * @runtime: PCM runtime instance
1194  * @cond: condition bits
1195  * @var: hw_params variable to apply the list constraint
1196  * @l: list
1197  *
1198  * Apply the list of constraints to an interval parameter.
1199  */
1200 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1201 			       unsigned int cond,
1202 			       snd_pcm_hw_param_t var,
1203 			       struct snd_pcm_hw_constraint_list *l)
1204 {
1205 	return snd_pcm_hw_rule_add(runtime, cond, var,
1206 				   snd_pcm_hw_rule_list, l,
1207 				   var, -1);
1208 }
1209 
1210 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1211 
1212 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1213 				   struct snd_pcm_hw_rule *rule)
1214 {
1215 	struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1216 	unsigned int num = 0, den = 0;
1217 	int err;
1218 	err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1219 				  r->nrats, r->rats, &num, &den);
1220 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1221 		params->rate_num = num;
1222 		params->rate_den = den;
1223 	}
1224 	return err;
1225 }
1226 
1227 /**
1228  * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1229  * @runtime: PCM runtime instance
1230  * @cond: condition bits
1231  * @var: hw_params variable to apply the ratnums constraint
1232  * @r: struct snd_ratnums constriants
1233  */
1234 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1235 				  unsigned int cond,
1236 				  snd_pcm_hw_param_t var,
1237 				  struct snd_pcm_hw_constraint_ratnums *r)
1238 {
1239 	return snd_pcm_hw_rule_add(runtime, cond, var,
1240 				   snd_pcm_hw_rule_ratnums, r,
1241 				   var, -1);
1242 }
1243 
1244 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1245 
1246 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1247 				   struct snd_pcm_hw_rule *rule)
1248 {
1249 	struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1250 	unsigned int num = 0, den = 0;
1251 	int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1252 				  r->nrats, r->rats, &num, &den);
1253 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1254 		params->rate_num = num;
1255 		params->rate_den = den;
1256 	}
1257 	return err;
1258 }
1259 
1260 /**
1261  * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1262  * @runtime: PCM runtime instance
1263  * @cond: condition bits
1264  * @var: hw_params variable to apply the ratdens constraint
1265  * @r: struct snd_ratdens constriants
1266  */
1267 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1268 				  unsigned int cond,
1269 				  snd_pcm_hw_param_t var,
1270 				  struct snd_pcm_hw_constraint_ratdens *r)
1271 {
1272 	return snd_pcm_hw_rule_add(runtime, cond, var,
1273 				   snd_pcm_hw_rule_ratdens, r,
1274 				   var, -1);
1275 }
1276 
1277 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1278 
1279 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1280 				  struct snd_pcm_hw_rule *rule)
1281 {
1282 	unsigned int l = (unsigned long) rule->private;
1283 	int width = l & 0xffff;
1284 	unsigned int msbits = l >> 16;
1285 	struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1286 	if (snd_interval_single(i) && snd_interval_value(i) == width)
1287 		params->msbits = msbits;
1288 	return 0;
1289 }
1290 
1291 /**
1292  * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1293  * @runtime: PCM runtime instance
1294  * @cond: condition bits
1295  * @width: sample bits width
1296  * @msbits: msbits width
1297  */
1298 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1299 				 unsigned int cond,
1300 				 unsigned int width,
1301 				 unsigned int msbits)
1302 {
1303 	unsigned long l = (msbits << 16) | width;
1304 	return snd_pcm_hw_rule_add(runtime, cond, -1,
1305 				    snd_pcm_hw_rule_msbits,
1306 				    (void*) l,
1307 				    SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1308 }
1309 
1310 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1311 
1312 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1313 				struct snd_pcm_hw_rule *rule)
1314 {
1315 	unsigned long step = (unsigned long) rule->private;
1316 	return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1317 }
1318 
1319 /**
1320  * snd_pcm_hw_constraint_step - add a hw constraint step rule
1321  * @runtime: PCM runtime instance
1322  * @cond: condition bits
1323  * @var: hw_params variable to apply the step constraint
1324  * @step: step size
1325  */
1326 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1327 			       unsigned int cond,
1328 			       snd_pcm_hw_param_t var,
1329 			       unsigned long step)
1330 {
1331 	return snd_pcm_hw_rule_add(runtime, cond, var,
1332 				   snd_pcm_hw_rule_step, (void *) step,
1333 				   var, -1);
1334 }
1335 
1336 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1337 
1338 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1339 {
1340 	static unsigned int pow2_sizes[] = {
1341 		1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1342 		1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1343 		1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1344 		1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1345 	};
1346 	return snd_interval_list(hw_param_interval(params, rule->var),
1347 				 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1348 }
1349 
1350 /**
1351  * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1352  * @runtime: PCM runtime instance
1353  * @cond: condition bits
1354  * @var: hw_params variable to apply the power-of-2 constraint
1355  */
1356 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1357 			       unsigned int cond,
1358 			       snd_pcm_hw_param_t var)
1359 {
1360 	return snd_pcm_hw_rule_add(runtime, cond, var,
1361 				   snd_pcm_hw_rule_pow2, NULL,
1362 				   var, -1);
1363 }
1364 
1365 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1366 
1367 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1368 				  snd_pcm_hw_param_t var)
1369 {
1370 	if (hw_is_mask(var)) {
1371 		snd_mask_any(hw_param_mask(params, var));
1372 		params->cmask |= 1 << var;
1373 		params->rmask |= 1 << var;
1374 		return;
1375 	}
1376 	if (hw_is_interval(var)) {
1377 		snd_interval_any(hw_param_interval(params, var));
1378 		params->cmask |= 1 << var;
1379 		params->rmask |= 1 << var;
1380 		return;
1381 	}
1382 	snd_BUG();
1383 }
1384 
1385 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1386 {
1387 	unsigned int k;
1388 	memset(params, 0, sizeof(*params));
1389 	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1390 		_snd_pcm_hw_param_any(params, k);
1391 	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1392 		_snd_pcm_hw_param_any(params, k);
1393 	params->info = ~0U;
1394 }
1395 
1396 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1397 
1398 /**
1399  * snd_pcm_hw_param_value - return @params field @var value
1400  * @params: the hw_params instance
1401  * @var: parameter to retrieve
1402  * @dir: pointer to the direction (-1,0,1) or %NULL
1403  *
1404  * Return the value for field @var if it's fixed in configuration space
1405  * defined by @params. Return -%EINVAL otherwise.
1406  */
1407 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1408 			   snd_pcm_hw_param_t var, int *dir)
1409 {
1410 	if (hw_is_mask(var)) {
1411 		const struct snd_mask *mask = hw_param_mask_c(params, var);
1412 		if (!snd_mask_single(mask))
1413 			return -EINVAL;
1414 		if (dir)
1415 			*dir = 0;
1416 		return snd_mask_value(mask);
1417 	}
1418 	if (hw_is_interval(var)) {
1419 		const struct snd_interval *i = hw_param_interval_c(params, var);
1420 		if (!snd_interval_single(i))
1421 			return -EINVAL;
1422 		if (dir)
1423 			*dir = i->openmin;
1424 		return snd_interval_value(i);
1425 	}
1426 	return -EINVAL;
1427 }
1428 
1429 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1430 
1431 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1432 				snd_pcm_hw_param_t var)
1433 {
1434 	if (hw_is_mask(var)) {
1435 		snd_mask_none(hw_param_mask(params, var));
1436 		params->cmask |= 1 << var;
1437 		params->rmask |= 1 << var;
1438 	} else if (hw_is_interval(var)) {
1439 		snd_interval_none(hw_param_interval(params, var));
1440 		params->cmask |= 1 << var;
1441 		params->rmask |= 1 << var;
1442 	} else {
1443 		snd_BUG();
1444 	}
1445 }
1446 
1447 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1448 
1449 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1450 				   snd_pcm_hw_param_t var)
1451 {
1452 	int changed;
1453 	if (hw_is_mask(var))
1454 		changed = snd_mask_refine_first(hw_param_mask(params, var));
1455 	else if (hw_is_interval(var))
1456 		changed = snd_interval_refine_first(hw_param_interval(params, var));
1457 	else
1458 		return -EINVAL;
1459 	if (changed) {
1460 		params->cmask |= 1 << var;
1461 		params->rmask |= 1 << var;
1462 	}
1463 	return changed;
1464 }
1465 
1466 
1467 /**
1468  * snd_pcm_hw_param_first - refine config space and return minimum value
1469  * @pcm: PCM instance
1470  * @params: the hw_params instance
1471  * @var: parameter to retrieve
1472  * @dir: pointer to the direction (-1,0,1) or %NULL
1473  *
1474  * Inside configuration space defined by @params remove from @var all
1475  * values > minimum. Reduce configuration space accordingly.
1476  * Return the minimum.
1477  */
1478 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1479 			   struct snd_pcm_hw_params *params,
1480 			   snd_pcm_hw_param_t var, int *dir)
1481 {
1482 	int changed = _snd_pcm_hw_param_first(params, var);
1483 	if (changed < 0)
1484 		return changed;
1485 	if (params->rmask) {
1486 		int err = snd_pcm_hw_refine(pcm, params);
1487 		if (snd_BUG_ON(err < 0))
1488 			return err;
1489 	}
1490 	return snd_pcm_hw_param_value(params, var, dir);
1491 }
1492 
1493 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1494 
1495 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1496 				  snd_pcm_hw_param_t var)
1497 {
1498 	int changed;
1499 	if (hw_is_mask(var))
1500 		changed = snd_mask_refine_last(hw_param_mask(params, var));
1501 	else if (hw_is_interval(var))
1502 		changed = snd_interval_refine_last(hw_param_interval(params, var));
1503 	else
1504 		return -EINVAL;
1505 	if (changed) {
1506 		params->cmask |= 1 << var;
1507 		params->rmask |= 1 << var;
1508 	}
1509 	return changed;
1510 }
1511 
1512 
1513 /**
1514  * snd_pcm_hw_param_last - refine config space and return maximum value
1515  * @pcm: PCM instance
1516  * @params: the hw_params instance
1517  * @var: parameter to retrieve
1518  * @dir: pointer to the direction (-1,0,1) or %NULL
1519  *
1520  * Inside configuration space defined by @params remove from @var all
1521  * values < maximum. Reduce configuration space accordingly.
1522  * Return the maximum.
1523  */
1524 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1525 			  struct snd_pcm_hw_params *params,
1526 			  snd_pcm_hw_param_t var, int *dir)
1527 {
1528 	int changed = _snd_pcm_hw_param_last(params, var);
1529 	if (changed < 0)
1530 		return changed;
1531 	if (params->rmask) {
1532 		int err = snd_pcm_hw_refine(pcm, params);
1533 		if (snd_BUG_ON(err < 0))
1534 			return err;
1535 	}
1536 	return snd_pcm_hw_param_value(params, var, dir);
1537 }
1538 
1539 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1540 
1541 /**
1542  * snd_pcm_hw_param_choose - choose a configuration defined by @params
1543  * @pcm: PCM instance
1544  * @params: the hw_params instance
1545  *
1546  * Choose one configuration from configuration space defined by @params.
1547  * The configuration chosen is that obtained fixing in this order:
1548  * first access, first format, first subformat, min channels,
1549  * min rate, min period time, max buffer size, min tick time
1550  */
1551 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1552 			     struct snd_pcm_hw_params *params)
1553 {
1554 	static int vars[] = {
1555 		SNDRV_PCM_HW_PARAM_ACCESS,
1556 		SNDRV_PCM_HW_PARAM_FORMAT,
1557 		SNDRV_PCM_HW_PARAM_SUBFORMAT,
1558 		SNDRV_PCM_HW_PARAM_CHANNELS,
1559 		SNDRV_PCM_HW_PARAM_RATE,
1560 		SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1561 		SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1562 		SNDRV_PCM_HW_PARAM_TICK_TIME,
1563 		-1
1564 	};
1565 	int err, *v;
1566 
1567 	for (v = vars; *v != -1; v++) {
1568 		if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1569 			err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1570 		else
1571 			err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1572 		if (snd_BUG_ON(err < 0))
1573 			return err;
1574 	}
1575 	return 0;
1576 }
1577 
1578 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1579 				   void *arg)
1580 {
1581 	struct snd_pcm_runtime *runtime = substream->runtime;
1582 	unsigned long flags;
1583 	snd_pcm_stream_lock_irqsave(substream, flags);
1584 	if (snd_pcm_running(substream) &&
1585 	    snd_pcm_update_hw_ptr(substream) >= 0)
1586 		runtime->status->hw_ptr %= runtime->buffer_size;
1587 	else
1588 		runtime->status->hw_ptr = 0;
1589 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1590 	return 0;
1591 }
1592 
1593 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1594 					  void *arg)
1595 {
1596 	struct snd_pcm_channel_info *info = arg;
1597 	struct snd_pcm_runtime *runtime = substream->runtime;
1598 	int width;
1599 	if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1600 		info->offset = -1;
1601 		return 0;
1602 	}
1603 	width = snd_pcm_format_physical_width(runtime->format);
1604 	if (width < 0)
1605 		return width;
1606 	info->offset = 0;
1607 	switch (runtime->access) {
1608 	case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1609 	case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1610 		info->first = info->channel * width;
1611 		info->step = runtime->channels * width;
1612 		break;
1613 	case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1614 	case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1615 	{
1616 		size_t size = runtime->dma_bytes / runtime->channels;
1617 		info->first = info->channel * size * 8;
1618 		info->step = width;
1619 		break;
1620 	}
1621 	default:
1622 		snd_BUG();
1623 		break;
1624 	}
1625 	return 0;
1626 }
1627 
1628 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1629 				       void *arg)
1630 {
1631 	struct snd_pcm_hw_params *params = arg;
1632 	snd_pcm_format_t format;
1633 	int channels, width;
1634 
1635 	params->fifo_size = substream->runtime->hw.fifo_size;
1636 	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1637 		format = params_format(params);
1638 		channels = params_channels(params);
1639 		width = snd_pcm_format_physical_width(format);
1640 		params->fifo_size /= width * channels;
1641 	}
1642 	return 0;
1643 }
1644 
1645 /**
1646  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1647  * @substream: the pcm substream instance
1648  * @cmd: ioctl command
1649  * @arg: ioctl argument
1650  *
1651  * Processes the generic ioctl commands for PCM.
1652  * Can be passed as the ioctl callback for PCM ops.
1653  *
1654  * Returns zero if successful, or a negative error code on failure.
1655  */
1656 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1657 		      unsigned int cmd, void *arg)
1658 {
1659 	switch (cmd) {
1660 	case SNDRV_PCM_IOCTL1_INFO:
1661 		return 0;
1662 	case SNDRV_PCM_IOCTL1_RESET:
1663 		return snd_pcm_lib_ioctl_reset(substream, arg);
1664 	case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1665 		return snd_pcm_lib_ioctl_channel_info(substream, arg);
1666 	case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1667 		return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1668 	}
1669 	return -ENXIO;
1670 }
1671 
1672 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1673 
1674 /**
1675  * snd_pcm_period_elapsed - update the pcm status for the next period
1676  * @substream: the pcm substream instance
1677  *
1678  * This function is called from the interrupt handler when the
1679  * PCM has processed the period size.  It will update the current
1680  * pointer, wake up sleepers, etc.
1681  *
1682  * Even if more than one periods have elapsed since the last call, you
1683  * have to call this only once.
1684  */
1685 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1686 {
1687 	struct snd_pcm_runtime *runtime;
1688 	unsigned long flags;
1689 
1690 	if (PCM_RUNTIME_CHECK(substream))
1691 		return;
1692 	runtime = substream->runtime;
1693 
1694 	if (runtime->transfer_ack_begin)
1695 		runtime->transfer_ack_begin(substream);
1696 
1697 	snd_pcm_stream_lock_irqsave(substream, flags);
1698 	if (!snd_pcm_running(substream) ||
1699 	    snd_pcm_update_hw_ptr0(substream, 1) < 0)
1700 		goto _end;
1701 
1702 	if (substream->timer_running)
1703 		snd_timer_interrupt(substream->timer, 1);
1704  _end:
1705 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1706 	if (runtime->transfer_ack_end)
1707 		runtime->transfer_ack_end(substream);
1708 	kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1709 }
1710 
1711 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1712 
1713 /*
1714  * Wait until avail_min data becomes available
1715  * Returns a negative error code if any error occurs during operation.
1716  * The available space is stored on availp.  When err = 0 and avail = 0
1717  * on the capture stream, it indicates the stream is in DRAINING state.
1718  */
1719 static int wait_for_avail(struct snd_pcm_substream *substream,
1720 			      snd_pcm_uframes_t *availp)
1721 {
1722 	struct snd_pcm_runtime *runtime = substream->runtime;
1723 	int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1724 	wait_queue_t wait;
1725 	int err = 0;
1726 	snd_pcm_uframes_t avail = 0;
1727 	long tout;
1728 
1729 	init_waitqueue_entry(&wait, current);
1730 	add_wait_queue(&runtime->tsleep, &wait);
1731 	for (;;) {
1732 		if (signal_pending(current)) {
1733 			err = -ERESTARTSYS;
1734 			break;
1735 		}
1736 		set_current_state(TASK_INTERRUPTIBLE);
1737 		snd_pcm_stream_unlock_irq(substream);
1738 		tout = schedule_timeout(msecs_to_jiffies(10000));
1739 		snd_pcm_stream_lock_irq(substream);
1740 		switch (runtime->status->state) {
1741 		case SNDRV_PCM_STATE_SUSPENDED:
1742 			err = -ESTRPIPE;
1743 			goto _endloop;
1744 		case SNDRV_PCM_STATE_XRUN:
1745 			err = -EPIPE;
1746 			goto _endloop;
1747 		case SNDRV_PCM_STATE_DRAINING:
1748 			if (is_playback)
1749 				err = -EPIPE;
1750 			else
1751 				avail = 0; /* indicate draining */
1752 			goto _endloop;
1753 		case SNDRV_PCM_STATE_OPEN:
1754 		case SNDRV_PCM_STATE_SETUP:
1755 		case SNDRV_PCM_STATE_DISCONNECTED:
1756 			err = -EBADFD;
1757 			goto _endloop;
1758 		}
1759 		if (!tout) {
1760 			snd_printd("%s write error (DMA or IRQ trouble?)\n",
1761 				   is_playback ? "playback" : "capture");
1762 			err = -EIO;
1763 			break;
1764 		}
1765 		if (is_playback)
1766 			avail = snd_pcm_playback_avail(runtime);
1767 		else
1768 			avail = snd_pcm_capture_avail(runtime);
1769 		if (avail >= runtime->twake)
1770 			break;
1771 	}
1772  _endloop:
1773 	remove_wait_queue(&runtime->tsleep, &wait);
1774 	*availp = avail;
1775 	return err;
1776 }
1777 
1778 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1779 				      unsigned int hwoff,
1780 				      unsigned long data, unsigned int off,
1781 				      snd_pcm_uframes_t frames)
1782 {
1783 	struct snd_pcm_runtime *runtime = substream->runtime;
1784 	int err;
1785 	char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1786 	if (substream->ops->copy) {
1787 		if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1788 			return err;
1789 	} else {
1790 		char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1791 		if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1792 			return -EFAULT;
1793 	}
1794 	return 0;
1795 }
1796 
1797 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1798 			  unsigned long data, unsigned int off,
1799 			  snd_pcm_uframes_t size);
1800 
1801 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1802 					    unsigned long data,
1803 					    snd_pcm_uframes_t size,
1804 					    int nonblock,
1805 					    transfer_f transfer)
1806 {
1807 	struct snd_pcm_runtime *runtime = substream->runtime;
1808 	snd_pcm_uframes_t xfer = 0;
1809 	snd_pcm_uframes_t offset = 0;
1810 	int err = 0;
1811 
1812 	if (size == 0)
1813 		return 0;
1814 
1815 	snd_pcm_stream_lock_irq(substream);
1816 	switch (runtime->status->state) {
1817 	case SNDRV_PCM_STATE_PREPARED:
1818 	case SNDRV_PCM_STATE_RUNNING:
1819 	case SNDRV_PCM_STATE_PAUSED:
1820 		break;
1821 	case SNDRV_PCM_STATE_XRUN:
1822 		err = -EPIPE;
1823 		goto _end_unlock;
1824 	case SNDRV_PCM_STATE_SUSPENDED:
1825 		err = -ESTRPIPE;
1826 		goto _end_unlock;
1827 	default:
1828 		err = -EBADFD;
1829 		goto _end_unlock;
1830 	}
1831 
1832 	runtime->twake = runtime->control->avail_min ? : 1;
1833 	while (size > 0) {
1834 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1835 		snd_pcm_uframes_t avail;
1836 		snd_pcm_uframes_t cont;
1837 		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1838 			snd_pcm_update_hw_ptr(substream);
1839 		avail = snd_pcm_playback_avail(runtime);
1840 		if (!avail) {
1841 			if (nonblock) {
1842 				err = -EAGAIN;
1843 				goto _end_unlock;
1844 			}
1845 			runtime->twake = min_t(snd_pcm_uframes_t, size,
1846 					runtime->control->avail_min ? : 1);
1847 			err = wait_for_avail(substream, &avail);
1848 			if (err < 0)
1849 				goto _end_unlock;
1850 		}
1851 		frames = size > avail ? avail : size;
1852 		cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1853 		if (frames > cont)
1854 			frames = cont;
1855 		if (snd_BUG_ON(!frames)) {
1856 			runtime->twake = 0;
1857 			snd_pcm_stream_unlock_irq(substream);
1858 			return -EINVAL;
1859 		}
1860 		appl_ptr = runtime->control->appl_ptr;
1861 		appl_ofs = appl_ptr % runtime->buffer_size;
1862 		snd_pcm_stream_unlock_irq(substream);
1863 		err = transfer(substream, appl_ofs, data, offset, frames);
1864 		snd_pcm_stream_lock_irq(substream);
1865 		if (err < 0)
1866 			goto _end_unlock;
1867 		switch (runtime->status->state) {
1868 		case SNDRV_PCM_STATE_XRUN:
1869 			err = -EPIPE;
1870 			goto _end_unlock;
1871 		case SNDRV_PCM_STATE_SUSPENDED:
1872 			err = -ESTRPIPE;
1873 			goto _end_unlock;
1874 		default:
1875 			break;
1876 		}
1877 		appl_ptr += frames;
1878 		if (appl_ptr >= runtime->boundary)
1879 			appl_ptr -= runtime->boundary;
1880 		runtime->control->appl_ptr = appl_ptr;
1881 		if (substream->ops->ack)
1882 			substream->ops->ack(substream);
1883 
1884 		offset += frames;
1885 		size -= frames;
1886 		xfer += frames;
1887 		if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1888 		    snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1889 			err = snd_pcm_start(substream);
1890 			if (err < 0)
1891 				goto _end_unlock;
1892 		}
1893 	}
1894  _end_unlock:
1895 	runtime->twake = 0;
1896 	if (xfer > 0 && err >= 0)
1897 		snd_pcm_update_state(substream, runtime);
1898 	snd_pcm_stream_unlock_irq(substream);
1899 	return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
1900 }
1901 
1902 /* sanity-check for read/write methods */
1903 static int pcm_sanity_check(struct snd_pcm_substream *substream)
1904 {
1905 	struct snd_pcm_runtime *runtime;
1906 	if (PCM_RUNTIME_CHECK(substream))
1907 		return -ENXIO;
1908 	runtime = substream->runtime;
1909 	if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
1910 		return -EINVAL;
1911 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1912 		return -EBADFD;
1913 	return 0;
1914 }
1915 
1916 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
1917 {
1918 	struct snd_pcm_runtime *runtime;
1919 	int nonblock;
1920 	int err;
1921 
1922 	err = pcm_sanity_check(substream);
1923 	if (err < 0)
1924 		return err;
1925 	runtime = substream->runtime;
1926 	nonblock = !!(substream->f_flags & O_NONBLOCK);
1927 
1928 	if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
1929 	    runtime->channels > 1)
1930 		return -EINVAL;
1931 	return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
1932 				  snd_pcm_lib_write_transfer);
1933 }
1934 
1935 EXPORT_SYMBOL(snd_pcm_lib_write);
1936 
1937 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
1938 				       unsigned int hwoff,
1939 				       unsigned long data, unsigned int off,
1940 				       snd_pcm_uframes_t frames)
1941 {
1942 	struct snd_pcm_runtime *runtime = substream->runtime;
1943 	int err;
1944 	void __user **bufs = (void __user **)data;
1945 	int channels = runtime->channels;
1946 	int c;
1947 	if (substream->ops->copy) {
1948 		if (snd_BUG_ON(!substream->ops->silence))
1949 			return -EINVAL;
1950 		for (c = 0; c < channels; ++c, ++bufs) {
1951 			if (*bufs == NULL) {
1952 				if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
1953 					return err;
1954 			} else {
1955 				char __user *buf = *bufs + samples_to_bytes(runtime, off);
1956 				if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
1957 					return err;
1958 			}
1959 		}
1960 	} else {
1961 		/* default transfer behaviour */
1962 		size_t dma_csize = runtime->dma_bytes / channels;
1963 		for (c = 0; c < channels; ++c, ++bufs) {
1964 			char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
1965 			if (*bufs == NULL) {
1966 				snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
1967 			} else {
1968 				char __user *buf = *bufs + samples_to_bytes(runtime, off);
1969 				if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
1970 					return -EFAULT;
1971 			}
1972 		}
1973 	}
1974 	return 0;
1975 }
1976 
1977 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
1978 				     void __user **bufs,
1979 				     snd_pcm_uframes_t frames)
1980 {
1981 	struct snd_pcm_runtime *runtime;
1982 	int nonblock;
1983 	int err;
1984 
1985 	err = pcm_sanity_check(substream);
1986 	if (err < 0)
1987 		return err;
1988 	runtime = substream->runtime;
1989 	nonblock = !!(substream->f_flags & O_NONBLOCK);
1990 
1991 	if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
1992 		return -EINVAL;
1993 	return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
1994 				  nonblock, snd_pcm_lib_writev_transfer);
1995 }
1996 
1997 EXPORT_SYMBOL(snd_pcm_lib_writev);
1998 
1999 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
2000 				     unsigned int hwoff,
2001 				     unsigned long data, unsigned int off,
2002 				     snd_pcm_uframes_t frames)
2003 {
2004 	struct snd_pcm_runtime *runtime = substream->runtime;
2005 	int err;
2006 	char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2007 	if (substream->ops->copy) {
2008 		if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2009 			return err;
2010 	} else {
2011 		char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2012 		if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2013 			return -EFAULT;
2014 	}
2015 	return 0;
2016 }
2017 
2018 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2019 					   unsigned long data,
2020 					   snd_pcm_uframes_t size,
2021 					   int nonblock,
2022 					   transfer_f transfer)
2023 {
2024 	struct snd_pcm_runtime *runtime = substream->runtime;
2025 	snd_pcm_uframes_t xfer = 0;
2026 	snd_pcm_uframes_t offset = 0;
2027 	int err = 0;
2028 
2029 	if (size == 0)
2030 		return 0;
2031 
2032 	snd_pcm_stream_lock_irq(substream);
2033 	switch (runtime->status->state) {
2034 	case SNDRV_PCM_STATE_PREPARED:
2035 		if (size >= runtime->start_threshold) {
2036 			err = snd_pcm_start(substream);
2037 			if (err < 0)
2038 				goto _end_unlock;
2039 		}
2040 		break;
2041 	case SNDRV_PCM_STATE_DRAINING:
2042 	case SNDRV_PCM_STATE_RUNNING:
2043 	case SNDRV_PCM_STATE_PAUSED:
2044 		break;
2045 	case SNDRV_PCM_STATE_XRUN:
2046 		err = -EPIPE;
2047 		goto _end_unlock;
2048 	case SNDRV_PCM_STATE_SUSPENDED:
2049 		err = -ESTRPIPE;
2050 		goto _end_unlock;
2051 	default:
2052 		err = -EBADFD;
2053 		goto _end_unlock;
2054 	}
2055 
2056 	runtime->twake = runtime->control->avail_min ? : 1;
2057 	while (size > 0) {
2058 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2059 		snd_pcm_uframes_t avail;
2060 		snd_pcm_uframes_t cont;
2061 		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2062 			snd_pcm_update_hw_ptr(substream);
2063 		avail = snd_pcm_capture_avail(runtime);
2064 		if (!avail) {
2065 			if (runtime->status->state ==
2066 			    SNDRV_PCM_STATE_DRAINING) {
2067 				snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2068 				goto _end_unlock;
2069 			}
2070 			if (nonblock) {
2071 				err = -EAGAIN;
2072 				goto _end_unlock;
2073 			}
2074 			runtime->twake = min_t(snd_pcm_uframes_t, size,
2075 					runtime->control->avail_min ? : 1);
2076 			err = wait_for_avail(substream, &avail);
2077 			if (err < 0)
2078 				goto _end_unlock;
2079 			if (!avail)
2080 				continue; /* draining */
2081 		}
2082 		frames = size > avail ? avail : size;
2083 		cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2084 		if (frames > cont)
2085 			frames = cont;
2086 		if (snd_BUG_ON(!frames)) {
2087 			runtime->twake = 0;
2088 			snd_pcm_stream_unlock_irq(substream);
2089 			return -EINVAL;
2090 		}
2091 		appl_ptr = runtime->control->appl_ptr;
2092 		appl_ofs = appl_ptr % runtime->buffer_size;
2093 		snd_pcm_stream_unlock_irq(substream);
2094 		err = transfer(substream, appl_ofs, data, offset, frames);
2095 		snd_pcm_stream_lock_irq(substream);
2096 		if (err < 0)
2097 			goto _end_unlock;
2098 		switch (runtime->status->state) {
2099 		case SNDRV_PCM_STATE_XRUN:
2100 			err = -EPIPE;
2101 			goto _end_unlock;
2102 		case SNDRV_PCM_STATE_SUSPENDED:
2103 			err = -ESTRPIPE;
2104 			goto _end_unlock;
2105 		default:
2106 			break;
2107 		}
2108 		appl_ptr += frames;
2109 		if (appl_ptr >= runtime->boundary)
2110 			appl_ptr -= runtime->boundary;
2111 		runtime->control->appl_ptr = appl_ptr;
2112 		if (substream->ops->ack)
2113 			substream->ops->ack(substream);
2114 
2115 		offset += frames;
2116 		size -= frames;
2117 		xfer += frames;
2118 	}
2119  _end_unlock:
2120 	runtime->twake = 0;
2121 	if (xfer > 0 && err >= 0)
2122 		snd_pcm_update_state(substream, runtime);
2123 	snd_pcm_stream_unlock_irq(substream);
2124 	return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2125 }
2126 
2127 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2128 {
2129 	struct snd_pcm_runtime *runtime;
2130 	int nonblock;
2131 	int err;
2132 
2133 	err = pcm_sanity_check(substream);
2134 	if (err < 0)
2135 		return err;
2136 	runtime = substream->runtime;
2137 	nonblock = !!(substream->f_flags & O_NONBLOCK);
2138 	if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2139 		return -EINVAL;
2140 	return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2141 }
2142 
2143 EXPORT_SYMBOL(snd_pcm_lib_read);
2144 
2145 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2146 				      unsigned int hwoff,
2147 				      unsigned long data, unsigned int off,
2148 				      snd_pcm_uframes_t frames)
2149 {
2150 	struct snd_pcm_runtime *runtime = substream->runtime;
2151 	int err;
2152 	void __user **bufs = (void __user **)data;
2153 	int channels = runtime->channels;
2154 	int c;
2155 	if (substream->ops->copy) {
2156 		for (c = 0; c < channels; ++c, ++bufs) {
2157 			char __user *buf;
2158 			if (*bufs == NULL)
2159 				continue;
2160 			buf = *bufs + samples_to_bytes(runtime, off);
2161 			if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2162 				return err;
2163 		}
2164 	} else {
2165 		snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2166 		for (c = 0; c < channels; ++c, ++bufs) {
2167 			char *hwbuf;
2168 			char __user *buf;
2169 			if (*bufs == NULL)
2170 				continue;
2171 
2172 			hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2173 			buf = *bufs + samples_to_bytes(runtime, off);
2174 			if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2175 				return -EFAULT;
2176 		}
2177 	}
2178 	return 0;
2179 }
2180 
2181 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2182 				    void __user **bufs,
2183 				    snd_pcm_uframes_t frames)
2184 {
2185 	struct snd_pcm_runtime *runtime;
2186 	int nonblock;
2187 	int err;
2188 
2189 	err = pcm_sanity_check(substream);
2190 	if (err < 0)
2191 		return err;
2192 	runtime = substream->runtime;
2193 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2194 		return -EBADFD;
2195 
2196 	nonblock = !!(substream->f_flags & O_NONBLOCK);
2197 	if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2198 		return -EINVAL;
2199 	return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2200 }
2201 
2202 EXPORT_SYMBOL(snd_pcm_lib_readv);
2203