xref: /openbmc/linux/sound/core/pcm_lib.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
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 			va_end(args);
1075 			return -ENOMEM;
1076 		}
1077 		if (constrs->rules) {
1078 			memcpy(new, constrs->rules,
1079 			       constrs->rules_num * sizeof(*c));
1080 			kfree(constrs->rules);
1081 		}
1082 		constrs->rules = new;
1083 		constrs->rules_all = new_rules;
1084 	}
1085 	c = &constrs->rules[constrs->rules_num];
1086 	c->cond = cond;
1087 	c->func = func;
1088 	c->var = var;
1089 	c->private = private;
1090 	k = 0;
1091 	while (1) {
1092 		if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1093 			va_end(args);
1094 			return -EINVAL;
1095 		}
1096 		c->deps[k++] = dep;
1097 		if (dep < 0)
1098 			break;
1099 		dep = va_arg(args, int);
1100 	}
1101 	constrs->rules_num++;
1102 	va_end(args);
1103 	return 0;
1104 }
1105 
1106 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1107 
1108 /**
1109  * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1110  * @runtime: PCM runtime instance
1111  * @var: hw_params variable to apply the mask
1112  * @mask: the bitmap mask
1113  *
1114  * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1115  */
1116 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1117 			       u_int32_t mask)
1118 {
1119 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1120 	struct snd_mask *maskp = constrs_mask(constrs, var);
1121 	*maskp->bits &= mask;
1122 	memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1123 	if (*maskp->bits == 0)
1124 		return -EINVAL;
1125 	return 0;
1126 }
1127 
1128 /**
1129  * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1130  * @runtime: PCM runtime instance
1131  * @var: hw_params variable to apply the mask
1132  * @mask: the 64bit bitmap mask
1133  *
1134  * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1135  */
1136 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1137 				 u_int64_t mask)
1138 {
1139 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1140 	struct snd_mask *maskp = constrs_mask(constrs, var);
1141 	maskp->bits[0] &= (u_int32_t)mask;
1142 	maskp->bits[1] &= (u_int32_t)(mask >> 32);
1143 	memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1144 	if (! maskp->bits[0] && ! maskp->bits[1])
1145 		return -EINVAL;
1146 	return 0;
1147 }
1148 
1149 /**
1150  * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1151  * @runtime: PCM runtime instance
1152  * @var: hw_params variable to apply the integer constraint
1153  *
1154  * Apply the constraint of integer to an interval parameter.
1155  */
1156 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1157 {
1158 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1159 	return snd_interval_setinteger(constrs_interval(constrs, var));
1160 }
1161 
1162 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1163 
1164 /**
1165  * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1166  * @runtime: PCM runtime instance
1167  * @var: hw_params variable to apply the range
1168  * @min: the minimal value
1169  * @max: the maximal value
1170  *
1171  * Apply the min/max range constraint to an interval parameter.
1172  */
1173 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1174 				 unsigned int min, unsigned int max)
1175 {
1176 	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1177 	struct snd_interval t;
1178 	t.min = min;
1179 	t.max = max;
1180 	t.openmin = t.openmax = 0;
1181 	t.integer = 0;
1182 	return snd_interval_refine(constrs_interval(constrs, var), &t);
1183 }
1184 
1185 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1186 
1187 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1188 				struct snd_pcm_hw_rule *rule)
1189 {
1190 	struct snd_pcm_hw_constraint_list *list = rule->private;
1191 	return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1192 }
1193 
1194 
1195 /**
1196  * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1197  * @runtime: PCM runtime instance
1198  * @cond: condition bits
1199  * @var: hw_params variable to apply the list constraint
1200  * @l: list
1201  *
1202  * Apply the list of constraints to an interval parameter.
1203  */
1204 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1205 			       unsigned int cond,
1206 			       snd_pcm_hw_param_t var,
1207 			       struct snd_pcm_hw_constraint_list *l)
1208 {
1209 	return snd_pcm_hw_rule_add(runtime, cond, var,
1210 				   snd_pcm_hw_rule_list, l,
1211 				   var, -1);
1212 }
1213 
1214 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1215 
1216 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1217 				   struct snd_pcm_hw_rule *rule)
1218 {
1219 	struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1220 	unsigned int num = 0, den = 0;
1221 	int err;
1222 	err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1223 				  r->nrats, r->rats, &num, &den);
1224 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1225 		params->rate_num = num;
1226 		params->rate_den = den;
1227 	}
1228 	return err;
1229 }
1230 
1231 /**
1232  * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1233  * @runtime: PCM runtime instance
1234  * @cond: condition bits
1235  * @var: hw_params variable to apply the ratnums constraint
1236  * @r: struct snd_ratnums constriants
1237  */
1238 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1239 				  unsigned int cond,
1240 				  snd_pcm_hw_param_t var,
1241 				  struct snd_pcm_hw_constraint_ratnums *r)
1242 {
1243 	return snd_pcm_hw_rule_add(runtime, cond, var,
1244 				   snd_pcm_hw_rule_ratnums, r,
1245 				   var, -1);
1246 }
1247 
1248 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1249 
1250 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1251 				   struct snd_pcm_hw_rule *rule)
1252 {
1253 	struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1254 	unsigned int num = 0, den = 0;
1255 	int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1256 				  r->nrats, r->rats, &num, &den);
1257 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1258 		params->rate_num = num;
1259 		params->rate_den = den;
1260 	}
1261 	return err;
1262 }
1263 
1264 /**
1265  * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1266  * @runtime: PCM runtime instance
1267  * @cond: condition bits
1268  * @var: hw_params variable to apply the ratdens constraint
1269  * @r: struct snd_ratdens constriants
1270  */
1271 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1272 				  unsigned int cond,
1273 				  snd_pcm_hw_param_t var,
1274 				  struct snd_pcm_hw_constraint_ratdens *r)
1275 {
1276 	return snd_pcm_hw_rule_add(runtime, cond, var,
1277 				   snd_pcm_hw_rule_ratdens, r,
1278 				   var, -1);
1279 }
1280 
1281 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1282 
1283 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1284 				  struct snd_pcm_hw_rule *rule)
1285 {
1286 	unsigned int l = (unsigned long) rule->private;
1287 	int width = l & 0xffff;
1288 	unsigned int msbits = l >> 16;
1289 	struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1290 	if (snd_interval_single(i) && snd_interval_value(i) == width)
1291 		params->msbits = msbits;
1292 	return 0;
1293 }
1294 
1295 /**
1296  * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1297  * @runtime: PCM runtime instance
1298  * @cond: condition bits
1299  * @width: sample bits width
1300  * @msbits: msbits width
1301  */
1302 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1303 				 unsigned int cond,
1304 				 unsigned int width,
1305 				 unsigned int msbits)
1306 {
1307 	unsigned long l = (msbits << 16) | width;
1308 	return snd_pcm_hw_rule_add(runtime, cond, -1,
1309 				    snd_pcm_hw_rule_msbits,
1310 				    (void*) l,
1311 				    SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1312 }
1313 
1314 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1315 
1316 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1317 				struct snd_pcm_hw_rule *rule)
1318 {
1319 	unsigned long step = (unsigned long) rule->private;
1320 	return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1321 }
1322 
1323 /**
1324  * snd_pcm_hw_constraint_step - add a hw constraint step rule
1325  * @runtime: PCM runtime instance
1326  * @cond: condition bits
1327  * @var: hw_params variable to apply the step constraint
1328  * @step: step size
1329  */
1330 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1331 			       unsigned int cond,
1332 			       snd_pcm_hw_param_t var,
1333 			       unsigned long step)
1334 {
1335 	return snd_pcm_hw_rule_add(runtime, cond, var,
1336 				   snd_pcm_hw_rule_step, (void *) step,
1337 				   var, -1);
1338 }
1339 
1340 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1341 
1342 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1343 {
1344 	static unsigned int pow2_sizes[] = {
1345 		1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1346 		1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1347 		1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1348 		1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1349 	};
1350 	return snd_interval_list(hw_param_interval(params, rule->var),
1351 				 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1352 }
1353 
1354 /**
1355  * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1356  * @runtime: PCM runtime instance
1357  * @cond: condition bits
1358  * @var: hw_params variable to apply the power-of-2 constraint
1359  */
1360 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1361 			       unsigned int cond,
1362 			       snd_pcm_hw_param_t var)
1363 {
1364 	return snd_pcm_hw_rule_add(runtime, cond, var,
1365 				   snd_pcm_hw_rule_pow2, NULL,
1366 				   var, -1);
1367 }
1368 
1369 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1370 
1371 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1372 				  snd_pcm_hw_param_t var)
1373 {
1374 	if (hw_is_mask(var)) {
1375 		snd_mask_any(hw_param_mask(params, var));
1376 		params->cmask |= 1 << var;
1377 		params->rmask |= 1 << var;
1378 		return;
1379 	}
1380 	if (hw_is_interval(var)) {
1381 		snd_interval_any(hw_param_interval(params, var));
1382 		params->cmask |= 1 << var;
1383 		params->rmask |= 1 << var;
1384 		return;
1385 	}
1386 	snd_BUG();
1387 }
1388 
1389 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1390 {
1391 	unsigned int k;
1392 	memset(params, 0, sizeof(*params));
1393 	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1394 		_snd_pcm_hw_param_any(params, k);
1395 	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1396 		_snd_pcm_hw_param_any(params, k);
1397 	params->info = ~0U;
1398 }
1399 
1400 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1401 
1402 /**
1403  * snd_pcm_hw_param_value - return @params field @var value
1404  * @params: the hw_params instance
1405  * @var: parameter to retrieve
1406  * @dir: pointer to the direction (-1,0,1) or %NULL
1407  *
1408  * Return the value for field @var if it's fixed in configuration space
1409  * defined by @params. Return -%EINVAL otherwise.
1410  */
1411 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1412 			   snd_pcm_hw_param_t var, int *dir)
1413 {
1414 	if (hw_is_mask(var)) {
1415 		const struct snd_mask *mask = hw_param_mask_c(params, var);
1416 		if (!snd_mask_single(mask))
1417 			return -EINVAL;
1418 		if (dir)
1419 			*dir = 0;
1420 		return snd_mask_value(mask);
1421 	}
1422 	if (hw_is_interval(var)) {
1423 		const struct snd_interval *i = hw_param_interval_c(params, var);
1424 		if (!snd_interval_single(i))
1425 			return -EINVAL;
1426 		if (dir)
1427 			*dir = i->openmin;
1428 		return snd_interval_value(i);
1429 	}
1430 	return -EINVAL;
1431 }
1432 
1433 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1434 
1435 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1436 				snd_pcm_hw_param_t var)
1437 {
1438 	if (hw_is_mask(var)) {
1439 		snd_mask_none(hw_param_mask(params, var));
1440 		params->cmask |= 1 << var;
1441 		params->rmask |= 1 << var;
1442 	} else if (hw_is_interval(var)) {
1443 		snd_interval_none(hw_param_interval(params, var));
1444 		params->cmask |= 1 << var;
1445 		params->rmask |= 1 << var;
1446 	} else {
1447 		snd_BUG();
1448 	}
1449 }
1450 
1451 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1452 
1453 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1454 				   snd_pcm_hw_param_t var)
1455 {
1456 	int changed;
1457 	if (hw_is_mask(var))
1458 		changed = snd_mask_refine_first(hw_param_mask(params, var));
1459 	else if (hw_is_interval(var))
1460 		changed = snd_interval_refine_first(hw_param_interval(params, var));
1461 	else
1462 		return -EINVAL;
1463 	if (changed) {
1464 		params->cmask |= 1 << var;
1465 		params->rmask |= 1 << var;
1466 	}
1467 	return changed;
1468 }
1469 
1470 
1471 /**
1472  * snd_pcm_hw_param_first - refine config space and return minimum value
1473  * @pcm: PCM instance
1474  * @params: the hw_params instance
1475  * @var: parameter to retrieve
1476  * @dir: pointer to the direction (-1,0,1) or %NULL
1477  *
1478  * Inside configuration space defined by @params remove from @var all
1479  * values > minimum. Reduce configuration space accordingly.
1480  * Return the minimum.
1481  */
1482 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1483 			   struct snd_pcm_hw_params *params,
1484 			   snd_pcm_hw_param_t var, int *dir)
1485 {
1486 	int changed = _snd_pcm_hw_param_first(params, var);
1487 	if (changed < 0)
1488 		return changed;
1489 	if (params->rmask) {
1490 		int err = snd_pcm_hw_refine(pcm, params);
1491 		if (snd_BUG_ON(err < 0))
1492 			return err;
1493 	}
1494 	return snd_pcm_hw_param_value(params, var, dir);
1495 }
1496 
1497 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1498 
1499 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1500 				  snd_pcm_hw_param_t var)
1501 {
1502 	int changed;
1503 	if (hw_is_mask(var))
1504 		changed = snd_mask_refine_last(hw_param_mask(params, var));
1505 	else if (hw_is_interval(var))
1506 		changed = snd_interval_refine_last(hw_param_interval(params, var));
1507 	else
1508 		return -EINVAL;
1509 	if (changed) {
1510 		params->cmask |= 1 << var;
1511 		params->rmask |= 1 << var;
1512 	}
1513 	return changed;
1514 }
1515 
1516 
1517 /**
1518  * snd_pcm_hw_param_last - refine config space and return maximum value
1519  * @pcm: PCM instance
1520  * @params: the hw_params instance
1521  * @var: parameter to retrieve
1522  * @dir: pointer to the direction (-1,0,1) or %NULL
1523  *
1524  * Inside configuration space defined by @params remove from @var all
1525  * values < maximum. Reduce configuration space accordingly.
1526  * Return the maximum.
1527  */
1528 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1529 			  struct snd_pcm_hw_params *params,
1530 			  snd_pcm_hw_param_t var, int *dir)
1531 {
1532 	int changed = _snd_pcm_hw_param_last(params, var);
1533 	if (changed < 0)
1534 		return changed;
1535 	if (params->rmask) {
1536 		int err = snd_pcm_hw_refine(pcm, params);
1537 		if (snd_BUG_ON(err < 0))
1538 			return err;
1539 	}
1540 	return snd_pcm_hw_param_value(params, var, dir);
1541 }
1542 
1543 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1544 
1545 /**
1546  * snd_pcm_hw_param_choose - choose a configuration defined by @params
1547  * @pcm: PCM instance
1548  * @params: the hw_params instance
1549  *
1550  * Choose one configuration from configuration space defined by @params.
1551  * The configuration chosen is that obtained fixing in this order:
1552  * first access, first format, first subformat, min channels,
1553  * min rate, min period time, max buffer size, min tick time
1554  */
1555 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1556 			     struct snd_pcm_hw_params *params)
1557 {
1558 	static int vars[] = {
1559 		SNDRV_PCM_HW_PARAM_ACCESS,
1560 		SNDRV_PCM_HW_PARAM_FORMAT,
1561 		SNDRV_PCM_HW_PARAM_SUBFORMAT,
1562 		SNDRV_PCM_HW_PARAM_CHANNELS,
1563 		SNDRV_PCM_HW_PARAM_RATE,
1564 		SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1565 		SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1566 		SNDRV_PCM_HW_PARAM_TICK_TIME,
1567 		-1
1568 	};
1569 	int err, *v;
1570 
1571 	for (v = vars; *v != -1; v++) {
1572 		if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1573 			err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1574 		else
1575 			err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1576 		if (snd_BUG_ON(err < 0))
1577 			return err;
1578 	}
1579 	return 0;
1580 }
1581 
1582 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1583 				   void *arg)
1584 {
1585 	struct snd_pcm_runtime *runtime = substream->runtime;
1586 	unsigned long flags;
1587 	snd_pcm_stream_lock_irqsave(substream, flags);
1588 	if (snd_pcm_running(substream) &&
1589 	    snd_pcm_update_hw_ptr(substream) >= 0)
1590 		runtime->status->hw_ptr %= runtime->buffer_size;
1591 	else
1592 		runtime->status->hw_ptr = 0;
1593 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1594 	return 0;
1595 }
1596 
1597 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1598 					  void *arg)
1599 {
1600 	struct snd_pcm_channel_info *info = arg;
1601 	struct snd_pcm_runtime *runtime = substream->runtime;
1602 	int width;
1603 	if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1604 		info->offset = -1;
1605 		return 0;
1606 	}
1607 	width = snd_pcm_format_physical_width(runtime->format);
1608 	if (width < 0)
1609 		return width;
1610 	info->offset = 0;
1611 	switch (runtime->access) {
1612 	case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1613 	case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1614 		info->first = info->channel * width;
1615 		info->step = runtime->channels * width;
1616 		break;
1617 	case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1618 	case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1619 	{
1620 		size_t size = runtime->dma_bytes / runtime->channels;
1621 		info->first = info->channel * size * 8;
1622 		info->step = width;
1623 		break;
1624 	}
1625 	default:
1626 		snd_BUG();
1627 		break;
1628 	}
1629 	return 0;
1630 }
1631 
1632 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1633 				       void *arg)
1634 {
1635 	struct snd_pcm_hw_params *params = arg;
1636 	snd_pcm_format_t format;
1637 	int channels, width;
1638 
1639 	params->fifo_size = substream->runtime->hw.fifo_size;
1640 	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1641 		format = params_format(params);
1642 		channels = params_channels(params);
1643 		width = snd_pcm_format_physical_width(format);
1644 		params->fifo_size /= width * channels;
1645 	}
1646 	return 0;
1647 }
1648 
1649 /**
1650  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1651  * @substream: the pcm substream instance
1652  * @cmd: ioctl command
1653  * @arg: ioctl argument
1654  *
1655  * Processes the generic ioctl commands for PCM.
1656  * Can be passed as the ioctl callback for PCM ops.
1657  *
1658  * Returns zero if successful, or a negative error code on failure.
1659  */
1660 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1661 		      unsigned int cmd, void *arg)
1662 {
1663 	switch (cmd) {
1664 	case SNDRV_PCM_IOCTL1_INFO:
1665 		return 0;
1666 	case SNDRV_PCM_IOCTL1_RESET:
1667 		return snd_pcm_lib_ioctl_reset(substream, arg);
1668 	case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1669 		return snd_pcm_lib_ioctl_channel_info(substream, arg);
1670 	case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1671 		return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1672 	}
1673 	return -ENXIO;
1674 }
1675 
1676 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1677 
1678 /**
1679  * snd_pcm_period_elapsed - update the pcm status for the next period
1680  * @substream: the pcm substream instance
1681  *
1682  * This function is called from the interrupt handler when the
1683  * PCM has processed the period size.  It will update the current
1684  * pointer, wake up sleepers, etc.
1685  *
1686  * Even if more than one periods have elapsed since the last call, you
1687  * have to call this only once.
1688  */
1689 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1690 {
1691 	struct snd_pcm_runtime *runtime;
1692 	unsigned long flags;
1693 
1694 	if (PCM_RUNTIME_CHECK(substream))
1695 		return;
1696 	runtime = substream->runtime;
1697 
1698 	if (runtime->transfer_ack_begin)
1699 		runtime->transfer_ack_begin(substream);
1700 
1701 	snd_pcm_stream_lock_irqsave(substream, flags);
1702 	if (!snd_pcm_running(substream) ||
1703 	    snd_pcm_update_hw_ptr0(substream, 1) < 0)
1704 		goto _end;
1705 
1706 	if (substream->timer_running)
1707 		snd_timer_interrupt(substream->timer, 1);
1708  _end:
1709 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1710 	if (runtime->transfer_ack_end)
1711 		runtime->transfer_ack_end(substream);
1712 	kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1713 }
1714 
1715 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1716 
1717 /*
1718  * Wait until avail_min data becomes available
1719  * Returns a negative error code if any error occurs during operation.
1720  * The available space is stored on availp.  When err = 0 and avail = 0
1721  * on the capture stream, it indicates the stream is in DRAINING state.
1722  */
1723 static int wait_for_avail(struct snd_pcm_substream *substream,
1724 			      snd_pcm_uframes_t *availp)
1725 {
1726 	struct snd_pcm_runtime *runtime = substream->runtime;
1727 	int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1728 	wait_queue_t wait;
1729 	int err = 0;
1730 	snd_pcm_uframes_t avail = 0;
1731 	long tout;
1732 
1733 	init_waitqueue_entry(&wait, current);
1734 	add_wait_queue(&runtime->tsleep, &wait);
1735 	for (;;) {
1736 		if (signal_pending(current)) {
1737 			err = -ERESTARTSYS;
1738 			break;
1739 		}
1740 		set_current_state(TASK_INTERRUPTIBLE);
1741 		snd_pcm_stream_unlock_irq(substream);
1742 		tout = schedule_timeout(msecs_to_jiffies(10000));
1743 		snd_pcm_stream_lock_irq(substream);
1744 		switch (runtime->status->state) {
1745 		case SNDRV_PCM_STATE_SUSPENDED:
1746 			err = -ESTRPIPE;
1747 			goto _endloop;
1748 		case SNDRV_PCM_STATE_XRUN:
1749 			err = -EPIPE;
1750 			goto _endloop;
1751 		case SNDRV_PCM_STATE_DRAINING:
1752 			if (is_playback)
1753 				err = -EPIPE;
1754 			else
1755 				avail = 0; /* indicate draining */
1756 			goto _endloop;
1757 		case SNDRV_PCM_STATE_OPEN:
1758 		case SNDRV_PCM_STATE_SETUP:
1759 		case SNDRV_PCM_STATE_DISCONNECTED:
1760 			err = -EBADFD;
1761 			goto _endloop;
1762 		}
1763 		if (!tout) {
1764 			snd_printd("%s write error (DMA or IRQ trouble?)\n",
1765 				   is_playback ? "playback" : "capture");
1766 			err = -EIO;
1767 			break;
1768 		}
1769 		if (is_playback)
1770 			avail = snd_pcm_playback_avail(runtime);
1771 		else
1772 			avail = snd_pcm_capture_avail(runtime);
1773 		if (avail >= runtime->twake)
1774 			break;
1775 	}
1776  _endloop:
1777 	remove_wait_queue(&runtime->tsleep, &wait);
1778 	*availp = avail;
1779 	return err;
1780 }
1781 
1782 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1783 				      unsigned int hwoff,
1784 				      unsigned long data, unsigned int off,
1785 				      snd_pcm_uframes_t frames)
1786 {
1787 	struct snd_pcm_runtime *runtime = substream->runtime;
1788 	int err;
1789 	char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1790 	if (substream->ops->copy) {
1791 		if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1792 			return err;
1793 	} else {
1794 		char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1795 		if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1796 			return -EFAULT;
1797 	}
1798 	return 0;
1799 }
1800 
1801 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1802 			  unsigned long data, unsigned int off,
1803 			  snd_pcm_uframes_t size);
1804 
1805 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1806 					    unsigned long data,
1807 					    snd_pcm_uframes_t size,
1808 					    int nonblock,
1809 					    transfer_f transfer)
1810 {
1811 	struct snd_pcm_runtime *runtime = substream->runtime;
1812 	snd_pcm_uframes_t xfer = 0;
1813 	snd_pcm_uframes_t offset = 0;
1814 	int err = 0;
1815 
1816 	if (size == 0)
1817 		return 0;
1818 
1819 	snd_pcm_stream_lock_irq(substream);
1820 	switch (runtime->status->state) {
1821 	case SNDRV_PCM_STATE_PREPARED:
1822 	case SNDRV_PCM_STATE_RUNNING:
1823 	case SNDRV_PCM_STATE_PAUSED:
1824 		break;
1825 	case SNDRV_PCM_STATE_XRUN:
1826 		err = -EPIPE;
1827 		goto _end_unlock;
1828 	case SNDRV_PCM_STATE_SUSPENDED:
1829 		err = -ESTRPIPE;
1830 		goto _end_unlock;
1831 	default:
1832 		err = -EBADFD;
1833 		goto _end_unlock;
1834 	}
1835 
1836 	runtime->twake = runtime->control->avail_min ? : 1;
1837 	while (size > 0) {
1838 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1839 		snd_pcm_uframes_t avail;
1840 		snd_pcm_uframes_t cont;
1841 		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1842 			snd_pcm_update_hw_ptr(substream);
1843 		avail = snd_pcm_playback_avail(runtime);
1844 		if (!avail) {
1845 			if (nonblock) {
1846 				err = -EAGAIN;
1847 				goto _end_unlock;
1848 			}
1849 			runtime->twake = min_t(snd_pcm_uframes_t, size,
1850 					runtime->control->avail_min ? : 1);
1851 			err = wait_for_avail(substream, &avail);
1852 			if (err < 0)
1853 				goto _end_unlock;
1854 		}
1855 		frames = size > avail ? avail : size;
1856 		cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1857 		if (frames > cont)
1858 			frames = cont;
1859 		if (snd_BUG_ON(!frames)) {
1860 			runtime->twake = 0;
1861 			snd_pcm_stream_unlock_irq(substream);
1862 			return -EINVAL;
1863 		}
1864 		appl_ptr = runtime->control->appl_ptr;
1865 		appl_ofs = appl_ptr % runtime->buffer_size;
1866 		snd_pcm_stream_unlock_irq(substream);
1867 		err = transfer(substream, appl_ofs, data, offset, frames);
1868 		snd_pcm_stream_lock_irq(substream);
1869 		if (err < 0)
1870 			goto _end_unlock;
1871 		switch (runtime->status->state) {
1872 		case SNDRV_PCM_STATE_XRUN:
1873 			err = -EPIPE;
1874 			goto _end_unlock;
1875 		case SNDRV_PCM_STATE_SUSPENDED:
1876 			err = -ESTRPIPE;
1877 			goto _end_unlock;
1878 		default:
1879 			break;
1880 		}
1881 		appl_ptr += frames;
1882 		if (appl_ptr >= runtime->boundary)
1883 			appl_ptr -= runtime->boundary;
1884 		runtime->control->appl_ptr = appl_ptr;
1885 		if (substream->ops->ack)
1886 			substream->ops->ack(substream);
1887 
1888 		offset += frames;
1889 		size -= frames;
1890 		xfer += frames;
1891 		if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1892 		    snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1893 			err = snd_pcm_start(substream);
1894 			if (err < 0)
1895 				goto _end_unlock;
1896 		}
1897 	}
1898  _end_unlock:
1899 	runtime->twake = 0;
1900 	if (xfer > 0 && err >= 0)
1901 		snd_pcm_update_state(substream, runtime);
1902 	snd_pcm_stream_unlock_irq(substream);
1903 	return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
1904 }
1905 
1906 /* sanity-check for read/write methods */
1907 static int pcm_sanity_check(struct snd_pcm_substream *substream)
1908 {
1909 	struct snd_pcm_runtime *runtime;
1910 	if (PCM_RUNTIME_CHECK(substream))
1911 		return -ENXIO;
1912 	runtime = substream->runtime;
1913 	if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
1914 		return -EINVAL;
1915 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1916 		return -EBADFD;
1917 	return 0;
1918 }
1919 
1920 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
1921 {
1922 	struct snd_pcm_runtime *runtime;
1923 	int nonblock;
1924 	int err;
1925 
1926 	err = pcm_sanity_check(substream);
1927 	if (err < 0)
1928 		return err;
1929 	runtime = substream->runtime;
1930 	nonblock = !!(substream->f_flags & O_NONBLOCK);
1931 
1932 	if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
1933 	    runtime->channels > 1)
1934 		return -EINVAL;
1935 	return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
1936 				  snd_pcm_lib_write_transfer);
1937 }
1938 
1939 EXPORT_SYMBOL(snd_pcm_lib_write);
1940 
1941 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
1942 				       unsigned int hwoff,
1943 				       unsigned long data, unsigned int off,
1944 				       snd_pcm_uframes_t frames)
1945 {
1946 	struct snd_pcm_runtime *runtime = substream->runtime;
1947 	int err;
1948 	void __user **bufs = (void __user **)data;
1949 	int channels = runtime->channels;
1950 	int c;
1951 	if (substream->ops->copy) {
1952 		if (snd_BUG_ON(!substream->ops->silence))
1953 			return -EINVAL;
1954 		for (c = 0; c < channels; ++c, ++bufs) {
1955 			if (*bufs == NULL) {
1956 				if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
1957 					return err;
1958 			} else {
1959 				char __user *buf = *bufs + samples_to_bytes(runtime, off);
1960 				if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
1961 					return err;
1962 			}
1963 		}
1964 	} else {
1965 		/* default transfer behaviour */
1966 		size_t dma_csize = runtime->dma_bytes / channels;
1967 		for (c = 0; c < channels; ++c, ++bufs) {
1968 			char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
1969 			if (*bufs == NULL) {
1970 				snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
1971 			} else {
1972 				char __user *buf = *bufs + samples_to_bytes(runtime, off);
1973 				if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
1974 					return -EFAULT;
1975 			}
1976 		}
1977 	}
1978 	return 0;
1979 }
1980 
1981 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
1982 				     void __user **bufs,
1983 				     snd_pcm_uframes_t frames)
1984 {
1985 	struct snd_pcm_runtime *runtime;
1986 	int nonblock;
1987 	int err;
1988 
1989 	err = pcm_sanity_check(substream);
1990 	if (err < 0)
1991 		return err;
1992 	runtime = substream->runtime;
1993 	nonblock = !!(substream->f_flags & O_NONBLOCK);
1994 
1995 	if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
1996 		return -EINVAL;
1997 	return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
1998 				  nonblock, snd_pcm_lib_writev_transfer);
1999 }
2000 
2001 EXPORT_SYMBOL(snd_pcm_lib_writev);
2002 
2003 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
2004 				     unsigned int hwoff,
2005 				     unsigned long data, unsigned int off,
2006 				     snd_pcm_uframes_t frames)
2007 {
2008 	struct snd_pcm_runtime *runtime = substream->runtime;
2009 	int err;
2010 	char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2011 	if (substream->ops->copy) {
2012 		if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2013 			return err;
2014 	} else {
2015 		char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2016 		if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2017 			return -EFAULT;
2018 	}
2019 	return 0;
2020 }
2021 
2022 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2023 					   unsigned long data,
2024 					   snd_pcm_uframes_t size,
2025 					   int nonblock,
2026 					   transfer_f transfer)
2027 {
2028 	struct snd_pcm_runtime *runtime = substream->runtime;
2029 	snd_pcm_uframes_t xfer = 0;
2030 	snd_pcm_uframes_t offset = 0;
2031 	int err = 0;
2032 
2033 	if (size == 0)
2034 		return 0;
2035 
2036 	snd_pcm_stream_lock_irq(substream);
2037 	switch (runtime->status->state) {
2038 	case SNDRV_PCM_STATE_PREPARED:
2039 		if (size >= runtime->start_threshold) {
2040 			err = snd_pcm_start(substream);
2041 			if (err < 0)
2042 				goto _end_unlock;
2043 		}
2044 		break;
2045 	case SNDRV_PCM_STATE_DRAINING:
2046 	case SNDRV_PCM_STATE_RUNNING:
2047 	case SNDRV_PCM_STATE_PAUSED:
2048 		break;
2049 	case SNDRV_PCM_STATE_XRUN:
2050 		err = -EPIPE;
2051 		goto _end_unlock;
2052 	case SNDRV_PCM_STATE_SUSPENDED:
2053 		err = -ESTRPIPE;
2054 		goto _end_unlock;
2055 	default:
2056 		err = -EBADFD;
2057 		goto _end_unlock;
2058 	}
2059 
2060 	runtime->twake = runtime->control->avail_min ? : 1;
2061 	while (size > 0) {
2062 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2063 		snd_pcm_uframes_t avail;
2064 		snd_pcm_uframes_t cont;
2065 		if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2066 			snd_pcm_update_hw_ptr(substream);
2067 		avail = snd_pcm_capture_avail(runtime);
2068 		if (!avail) {
2069 			if (runtime->status->state ==
2070 			    SNDRV_PCM_STATE_DRAINING) {
2071 				snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2072 				goto _end_unlock;
2073 			}
2074 			if (nonblock) {
2075 				err = -EAGAIN;
2076 				goto _end_unlock;
2077 			}
2078 			runtime->twake = min_t(snd_pcm_uframes_t, size,
2079 					runtime->control->avail_min ? : 1);
2080 			err = wait_for_avail(substream, &avail);
2081 			if (err < 0)
2082 				goto _end_unlock;
2083 			if (!avail)
2084 				continue; /* draining */
2085 		}
2086 		frames = size > avail ? avail : size;
2087 		cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2088 		if (frames > cont)
2089 			frames = cont;
2090 		if (snd_BUG_ON(!frames)) {
2091 			runtime->twake = 0;
2092 			snd_pcm_stream_unlock_irq(substream);
2093 			return -EINVAL;
2094 		}
2095 		appl_ptr = runtime->control->appl_ptr;
2096 		appl_ofs = appl_ptr % runtime->buffer_size;
2097 		snd_pcm_stream_unlock_irq(substream);
2098 		err = transfer(substream, appl_ofs, data, offset, frames);
2099 		snd_pcm_stream_lock_irq(substream);
2100 		if (err < 0)
2101 			goto _end_unlock;
2102 		switch (runtime->status->state) {
2103 		case SNDRV_PCM_STATE_XRUN:
2104 			err = -EPIPE;
2105 			goto _end_unlock;
2106 		case SNDRV_PCM_STATE_SUSPENDED:
2107 			err = -ESTRPIPE;
2108 			goto _end_unlock;
2109 		default:
2110 			break;
2111 		}
2112 		appl_ptr += frames;
2113 		if (appl_ptr >= runtime->boundary)
2114 			appl_ptr -= runtime->boundary;
2115 		runtime->control->appl_ptr = appl_ptr;
2116 		if (substream->ops->ack)
2117 			substream->ops->ack(substream);
2118 
2119 		offset += frames;
2120 		size -= frames;
2121 		xfer += frames;
2122 	}
2123  _end_unlock:
2124 	runtime->twake = 0;
2125 	if (xfer > 0 && err >= 0)
2126 		snd_pcm_update_state(substream, runtime);
2127 	snd_pcm_stream_unlock_irq(substream);
2128 	return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2129 }
2130 
2131 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2132 {
2133 	struct snd_pcm_runtime *runtime;
2134 	int nonblock;
2135 	int err;
2136 
2137 	err = pcm_sanity_check(substream);
2138 	if (err < 0)
2139 		return err;
2140 	runtime = substream->runtime;
2141 	nonblock = !!(substream->f_flags & O_NONBLOCK);
2142 	if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2143 		return -EINVAL;
2144 	return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2145 }
2146 
2147 EXPORT_SYMBOL(snd_pcm_lib_read);
2148 
2149 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2150 				      unsigned int hwoff,
2151 				      unsigned long data, unsigned int off,
2152 				      snd_pcm_uframes_t frames)
2153 {
2154 	struct snd_pcm_runtime *runtime = substream->runtime;
2155 	int err;
2156 	void __user **bufs = (void __user **)data;
2157 	int channels = runtime->channels;
2158 	int c;
2159 	if (substream->ops->copy) {
2160 		for (c = 0; c < channels; ++c, ++bufs) {
2161 			char __user *buf;
2162 			if (*bufs == NULL)
2163 				continue;
2164 			buf = *bufs + samples_to_bytes(runtime, off);
2165 			if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2166 				return err;
2167 		}
2168 	} else {
2169 		snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2170 		for (c = 0; c < channels; ++c, ++bufs) {
2171 			char *hwbuf;
2172 			char __user *buf;
2173 			if (*bufs == NULL)
2174 				continue;
2175 
2176 			hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2177 			buf = *bufs + samples_to_bytes(runtime, off);
2178 			if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2179 				return -EFAULT;
2180 		}
2181 	}
2182 	return 0;
2183 }
2184 
2185 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2186 				    void __user **bufs,
2187 				    snd_pcm_uframes_t frames)
2188 {
2189 	struct snd_pcm_runtime *runtime;
2190 	int nonblock;
2191 	int err;
2192 
2193 	err = pcm_sanity_check(substream);
2194 	if (err < 0)
2195 		return err;
2196 	runtime = substream->runtime;
2197 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2198 		return -EBADFD;
2199 
2200 	nonblock = !!(substream->f_flags & O_NONBLOCK);
2201 	if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2202 		return -EINVAL;
2203 	return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2204 }
2205 
2206 EXPORT_SYMBOL(snd_pcm_lib_readv);
2207