xref: /linux/sound/core/pcm_lib.c (revision 9ce7677cfd7cd871adb457c80bea3b581b839641)
1 /*
2  *  Digital Audio (PCM) abstract layer
3  *  Copyright (c) by Jaroslav Kysela <perex@suse.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 <sound/driver.h>
24 #include <linux/slab.h>
25 #include <linux/time.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(snd_pcm_substream_t *substream, snd_pcm_uframes_t new_hw_ptr)
43 {
44 	snd_pcm_runtime_t *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 		snd_assert(runtime->silence_filled <= runtime->buffer_size, return);
62 		noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
63 		if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
64 			return;
65 		frames = runtime->silence_threshold - noise_dist;
66 		if (frames > runtime->silence_size)
67 			frames = runtime->silence_size;
68 	} else {
69 		if (new_hw_ptr == ULONG_MAX) {	/* initialization */
70 			snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
71 			runtime->silence_filled = avail > 0 ? avail : 0;
72 			runtime->silence_start = (runtime->status->hw_ptr +
73 						  runtime->silence_filled) %
74 						 runtime->boundary;
75 		} else {
76 			ofs = runtime->status->hw_ptr;
77 			frames = new_hw_ptr - ofs;
78 			if ((snd_pcm_sframes_t)frames < 0)
79 				frames += runtime->boundary;
80 			runtime->silence_filled -= frames;
81 			if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
82 				runtime->silence_filled = 0;
83 				runtime->silence_start = (ofs + frames) - runtime->buffer_size;
84 			} else {
85 				runtime->silence_start = ofs - runtime->silence_filled;
86 			}
87 			if ((snd_pcm_sframes_t)runtime->silence_start < 0)
88 				runtime->silence_start += runtime->boundary;
89 		}
90 		frames = runtime->buffer_size - runtime->silence_filled;
91 	}
92 	snd_assert(frames <= runtime->buffer_size, return);
93 	if (frames == 0)
94 		return;
95 	ofs = (runtime->silence_start + runtime->silence_filled) % 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_assert(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_assert(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 xrun(snd_pcm_substream_t *substream)
132 {
133 	snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
134 #ifdef CONFIG_SND_DEBUG
135 	if (substream->pstr->xrun_debug) {
136 		snd_printd(KERN_DEBUG "XRUN: pcmC%dD%d%c\n",
137 			   substream->pcm->card->number,
138 			   substream->pcm->device,
139 			   substream->stream ? 'c' : 'p');
140 		if (substream->pstr->xrun_debug > 1)
141 			dump_stack();
142 	}
143 #endif
144 }
145 
146 static inline snd_pcm_uframes_t snd_pcm_update_hw_ptr_pos(snd_pcm_substream_t *substream,
147 							  snd_pcm_runtime_t *runtime)
148 {
149 	snd_pcm_uframes_t pos;
150 
151 	pos = substream->ops->pointer(substream);
152 	if (pos == SNDRV_PCM_POS_XRUN)
153 		return pos; /* XRUN */
154 	if (runtime->tstamp_mode & SNDRV_PCM_TSTAMP_MMAP)
155 		getnstimeofday((struct timespec *)&runtime->status->tstamp);
156 #ifdef CONFIG_SND_DEBUG
157 	if (pos >= runtime->buffer_size) {
158 		snd_printk(KERN_ERR  "BUG: stream = %i, pos = 0x%lx, buffer size = 0x%lx, period size = 0x%lx\n", substream->stream, pos, runtime->buffer_size, runtime->period_size);
159 	}
160 #endif
161 	pos -= pos % runtime->min_align;
162 	return pos;
163 }
164 
165 static inline int snd_pcm_update_hw_ptr_post(snd_pcm_substream_t *substream,
166 					     snd_pcm_runtime_t *runtime)
167 {
168 	snd_pcm_uframes_t avail;
169 
170 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
171 		avail = snd_pcm_playback_avail(runtime);
172 	else
173 		avail = snd_pcm_capture_avail(runtime);
174 	if (avail > runtime->avail_max)
175 		runtime->avail_max = avail;
176 	if (avail >= runtime->stop_threshold) {
177 		if (substream->runtime->status->state == SNDRV_PCM_STATE_DRAINING)
178 			snd_pcm_drain_done(substream);
179 		else
180 			xrun(substream);
181 		return -EPIPE;
182 	}
183 	if (avail >= runtime->control->avail_min)
184 		wake_up(&runtime->sleep);
185 	return 0;
186 }
187 
188 static inline int snd_pcm_update_hw_ptr_interrupt(snd_pcm_substream_t *substream)
189 {
190 	snd_pcm_runtime_t *runtime = substream->runtime;
191 	snd_pcm_uframes_t pos;
192 	snd_pcm_uframes_t new_hw_ptr, hw_ptr_interrupt;
193 	snd_pcm_sframes_t delta;
194 
195 	pos = snd_pcm_update_hw_ptr_pos(substream, runtime);
196 	if (pos == SNDRV_PCM_POS_XRUN) {
197 		xrun(substream);
198 		return -EPIPE;
199 	}
200 	if (runtime->period_size == runtime->buffer_size)
201 		goto __next_buf;
202 	new_hw_ptr = runtime->hw_ptr_base + pos;
203 	hw_ptr_interrupt = runtime->hw_ptr_interrupt + runtime->period_size;
204 
205 	delta = hw_ptr_interrupt - new_hw_ptr;
206 	if (delta > 0) {
207 		if ((snd_pcm_uframes_t)delta < runtime->buffer_size / 2) {
208 #ifdef CONFIG_SND_DEBUG
209 			if (runtime->periods > 1 && substream->pstr->xrun_debug) {
210 				snd_printd(KERN_ERR "Unexpected hw_pointer value [1] (stream = %i, delta: -%ld, max jitter = %ld): wrong interrupt acknowledge?\n", substream->stream, (long) delta, runtime->buffer_size / 2);
211 				if (substream->pstr->xrun_debug > 1)
212 					dump_stack();
213 			}
214 #endif
215 			return 0;
216 		}
217 	      __next_buf:
218 		runtime->hw_ptr_base += runtime->buffer_size;
219 		if (runtime->hw_ptr_base == runtime->boundary)
220 			runtime->hw_ptr_base = 0;
221 		new_hw_ptr = runtime->hw_ptr_base + pos;
222 	}
223 
224 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
225 	    runtime->silence_size > 0)
226 		snd_pcm_playback_silence(substream, new_hw_ptr);
227 
228 	runtime->status->hw_ptr = new_hw_ptr;
229 	runtime->hw_ptr_interrupt = new_hw_ptr - new_hw_ptr % runtime->period_size;
230 
231 	return snd_pcm_update_hw_ptr_post(substream, runtime);
232 }
233 
234 /* CAUTION: call it with irq disabled */
235 int snd_pcm_update_hw_ptr(snd_pcm_substream_t *substream)
236 {
237 	snd_pcm_runtime_t *runtime = substream->runtime;
238 	snd_pcm_uframes_t pos;
239 	snd_pcm_uframes_t old_hw_ptr, new_hw_ptr;
240 	snd_pcm_sframes_t delta;
241 
242 	old_hw_ptr = runtime->status->hw_ptr;
243 	pos = snd_pcm_update_hw_ptr_pos(substream, runtime);
244 	if (pos == SNDRV_PCM_POS_XRUN) {
245 		xrun(substream);
246 		return -EPIPE;
247 	}
248 	new_hw_ptr = runtime->hw_ptr_base + pos;
249 
250 	delta = old_hw_ptr - new_hw_ptr;
251 	if (delta > 0) {
252 		if ((snd_pcm_uframes_t)delta < runtime->buffer_size / 2) {
253 #ifdef CONFIG_SND_DEBUG
254 			if (runtime->periods > 2 && substream->pstr->xrun_debug) {
255 				snd_printd(KERN_ERR "Unexpected hw_pointer value [2] (stream = %i, delta: -%ld, max jitter = %ld): wrong interrupt acknowledge?\n", substream->stream, (long) delta, runtime->buffer_size / 2);
256 				if (substream->pstr->xrun_debug > 1)
257 					dump_stack();
258 			}
259 #endif
260 			return 0;
261 		}
262 		runtime->hw_ptr_base += runtime->buffer_size;
263 		if (runtime->hw_ptr_base == runtime->boundary)
264 			runtime->hw_ptr_base = 0;
265 		new_hw_ptr = runtime->hw_ptr_base + pos;
266 	}
267 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
268 	    runtime->silence_size > 0)
269 		snd_pcm_playback_silence(substream, new_hw_ptr);
270 
271 	runtime->status->hw_ptr = new_hw_ptr;
272 
273 	return snd_pcm_update_hw_ptr_post(substream, runtime);
274 }
275 
276 /**
277  * snd_pcm_set_ops - set the PCM operators
278  * @pcm: the pcm instance
279  * @direction: stream direction, SNDRV_PCM_STREAM_XXX
280  * @ops: the operator table
281  *
282  * Sets the given PCM operators to the pcm instance.
283  */
284 void snd_pcm_set_ops(snd_pcm_t *pcm, int direction, snd_pcm_ops_t *ops)
285 {
286 	snd_pcm_str_t *stream = &pcm->streams[direction];
287 	snd_pcm_substream_t *substream;
288 
289 	for (substream = stream->substream; substream != NULL; substream = substream->next)
290 		substream->ops = ops;
291 }
292 
293 
294 /**
295  * snd_pcm_sync - set the PCM sync id
296  * @substream: the pcm substream
297  *
298  * Sets the PCM sync identifier for the card.
299  */
300 void snd_pcm_set_sync(snd_pcm_substream_t * substream)
301 {
302 	snd_pcm_runtime_t *runtime = substream->runtime;
303 
304 	runtime->sync.id32[0] = substream->pcm->card->number;
305 	runtime->sync.id32[1] = -1;
306 	runtime->sync.id32[2] = -1;
307 	runtime->sync.id32[3] = -1;
308 }
309 
310 /*
311  *  Standard ioctl routine
312  */
313 
314 /* Code taken from alsa-lib */
315 #define assert(a) snd_assert((a), return -EINVAL)
316 
317 static inline unsigned int div32(unsigned int a, unsigned int b,
318 				 unsigned int *r)
319 {
320 	if (b == 0) {
321 		*r = 0;
322 		return UINT_MAX;
323 	}
324 	*r = a % b;
325 	return a / b;
326 }
327 
328 static inline unsigned int div_down(unsigned int a, unsigned int b)
329 {
330 	if (b == 0)
331 		return UINT_MAX;
332 	return a / b;
333 }
334 
335 static inline unsigned int div_up(unsigned int a, unsigned int b)
336 {
337 	unsigned int r;
338 	unsigned int q;
339 	if (b == 0)
340 		return UINT_MAX;
341 	q = div32(a, b, &r);
342 	if (r)
343 		++q;
344 	return q;
345 }
346 
347 static inline unsigned int mul(unsigned int a, unsigned int b)
348 {
349 	if (a == 0)
350 		return 0;
351 	if (div_down(UINT_MAX, a) < b)
352 		return UINT_MAX;
353 	return a * b;
354 }
355 
356 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
357 				    unsigned int c, unsigned int *r)
358 {
359 	u_int64_t n = (u_int64_t) a * b;
360 	if (c == 0) {
361 		snd_assert(n > 0, );
362 		*r = 0;
363 		return UINT_MAX;
364 	}
365 	div64_32(&n, c, r);
366 	if (n >= UINT_MAX) {
367 		*r = 0;
368 		return UINT_MAX;
369 	}
370 	return n;
371 }
372 
373 static int snd_interval_refine_min(snd_interval_t *i, unsigned int min, int openmin)
374 {
375 	int changed = 0;
376 	assert(!snd_interval_empty(i));
377 	if (i->min < min) {
378 		i->min = min;
379 		i->openmin = openmin;
380 		changed = 1;
381 	} else if (i->min == min && !i->openmin && openmin) {
382 		i->openmin = 1;
383 		changed = 1;
384 	}
385 	if (i->integer) {
386 		if (i->openmin) {
387 			i->min++;
388 			i->openmin = 0;
389 		}
390 	}
391 	if (snd_interval_checkempty(i)) {
392 		snd_interval_none(i);
393 		return -EINVAL;
394 	}
395 	return changed;
396 }
397 
398 static int snd_interval_refine_max(snd_interval_t *i, unsigned int max, int openmax)
399 {
400 	int changed = 0;
401 	assert(!snd_interval_empty(i));
402 	if (i->max > max) {
403 		i->max = max;
404 		i->openmax = openmax;
405 		changed = 1;
406 	} else if (i->max == max && !i->openmax && openmax) {
407 		i->openmax = 1;
408 		changed = 1;
409 	}
410 	if (i->integer) {
411 		if (i->openmax) {
412 			i->max--;
413 			i->openmax = 0;
414 		}
415 	}
416 	if (snd_interval_checkempty(i)) {
417 		snd_interval_none(i);
418 		return -EINVAL;
419 	}
420 	return changed;
421 }
422 
423 /**
424  * snd_interval_refine - refine the interval value of configurator
425  * @i: the interval value to refine
426  * @v: the interval value to refer to
427  *
428  * Refines the interval value with the reference value.
429  * The interval is changed to the range satisfying both intervals.
430  * The interval status (min, max, integer, etc.) are evaluated.
431  *
432  * Returns non-zero if the value is changed, zero if not changed.
433  */
434 int snd_interval_refine(snd_interval_t *i, const snd_interval_t *v)
435 {
436 	int changed = 0;
437 	assert(!snd_interval_empty(i));
438 	if (i->min < v->min) {
439 		i->min = v->min;
440 		i->openmin = v->openmin;
441 		changed = 1;
442 	} else if (i->min == v->min && !i->openmin && v->openmin) {
443 		i->openmin = 1;
444 		changed = 1;
445 	}
446 	if (i->max > v->max) {
447 		i->max = v->max;
448 		i->openmax = v->openmax;
449 		changed = 1;
450 	} else if (i->max == v->max && !i->openmax && v->openmax) {
451 		i->openmax = 1;
452 		changed = 1;
453 	}
454 	if (!i->integer && v->integer) {
455 		i->integer = 1;
456 		changed = 1;
457 	}
458 	if (i->integer) {
459 		if (i->openmin) {
460 			i->min++;
461 			i->openmin = 0;
462 		}
463 		if (i->openmax) {
464 			i->max--;
465 			i->openmax = 0;
466 		}
467 	} else if (!i->openmin && !i->openmax && i->min == i->max)
468 		i->integer = 1;
469 	if (snd_interval_checkempty(i)) {
470 		snd_interval_none(i);
471 		return -EINVAL;
472 	}
473 	return changed;
474 }
475 
476 static int snd_interval_refine_first(snd_interval_t *i)
477 {
478 	assert(!snd_interval_empty(i));
479 	if (snd_interval_single(i))
480 		return 0;
481 	i->max = i->min;
482 	i->openmax = i->openmin;
483 	if (i->openmax)
484 		i->max++;
485 	return 1;
486 }
487 
488 static int snd_interval_refine_last(snd_interval_t *i)
489 {
490 	assert(!snd_interval_empty(i));
491 	if (snd_interval_single(i))
492 		return 0;
493 	i->min = i->max;
494 	i->openmin = i->openmax;
495 	if (i->openmin)
496 		i->min--;
497 	return 1;
498 }
499 
500 static int snd_interval_refine_set(snd_interval_t *i, unsigned int val)
501 {
502 	snd_interval_t t;
503 	t.empty = 0;
504 	t.min = t.max = val;
505 	t.openmin = t.openmax = 0;
506 	t.integer = 1;
507 	return snd_interval_refine(i, &t);
508 }
509 
510 void snd_interval_mul(const snd_interval_t *a, const snd_interval_t *b, snd_interval_t *c)
511 {
512 	if (a->empty || b->empty) {
513 		snd_interval_none(c);
514 		return;
515 	}
516 	c->empty = 0;
517 	c->min = mul(a->min, b->min);
518 	c->openmin = (a->openmin || b->openmin);
519 	c->max = mul(a->max,  b->max);
520 	c->openmax = (a->openmax || b->openmax);
521 	c->integer = (a->integer && b->integer);
522 }
523 
524 /**
525  * snd_interval_div - refine the interval value with division
526  * @a: dividend
527  * @b: divisor
528  * @c: quotient
529  *
530  * c = a / b
531  *
532  * Returns non-zero if the value is changed, zero if not changed.
533  */
534 void snd_interval_div(const snd_interval_t *a, const snd_interval_t *b, snd_interval_t *c)
535 {
536 	unsigned int r;
537 	if (a->empty || b->empty) {
538 		snd_interval_none(c);
539 		return;
540 	}
541 	c->empty = 0;
542 	c->min = div32(a->min, b->max, &r);
543 	c->openmin = (r || a->openmin || b->openmax);
544 	if (b->min > 0) {
545 		c->max = div32(a->max, b->min, &r);
546 		if (r) {
547 			c->max++;
548 			c->openmax = 1;
549 		} else
550 			c->openmax = (a->openmax || b->openmin);
551 	} else {
552 		c->max = UINT_MAX;
553 		c->openmax = 0;
554 	}
555 	c->integer = 0;
556 }
557 
558 /**
559  * snd_interval_muldivk - refine the interval value
560  * @a: dividend 1
561  * @b: dividend 2
562  * @k: divisor (as integer)
563  * @c: result
564   *
565  * c = a * b / k
566  *
567  * Returns non-zero if the value is changed, zero if not changed.
568  */
569 void snd_interval_muldivk(const snd_interval_t *a, const snd_interval_t *b,
570 		      unsigned int k, snd_interval_t *c)
571 {
572 	unsigned int r;
573 	if (a->empty || b->empty) {
574 		snd_interval_none(c);
575 		return;
576 	}
577 	c->empty = 0;
578 	c->min = muldiv32(a->min, b->min, k, &r);
579 	c->openmin = (r || a->openmin || b->openmin);
580 	c->max = muldiv32(a->max, b->max, k, &r);
581 	if (r) {
582 		c->max++;
583 		c->openmax = 1;
584 	} else
585 		c->openmax = (a->openmax || b->openmax);
586 	c->integer = 0;
587 }
588 
589 /**
590  * snd_interval_mulkdiv - refine the interval value
591  * @a: dividend 1
592  * @k: dividend 2 (as integer)
593  * @b: divisor
594  * @c: result
595  *
596  * c = a * k / b
597  *
598  * Returns non-zero if the value is changed, zero if not changed.
599  */
600 void snd_interval_mulkdiv(const snd_interval_t *a, unsigned int k,
601 		      const snd_interval_t *b, snd_interval_t *c)
602 {
603 	unsigned int r;
604 	if (a->empty || b->empty) {
605 		snd_interval_none(c);
606 		return;
607 	}
608 	c->empty = 0;
609 	c->min = muldiv32(a->min, k, b->max, &r);
610 	c->openmin = (r || a->openmin || b->openmax);
611 	if (b->min > 0) {
612 		c->max = muldiv32(a->max, k, b->min, &r);
613 		if (r) {
614 			c->max++;
615 			c->openmax = 1;
616 		} else
617 			c->openmax = (a->openmax || b->openmin);
618 	} else {
619 		c->max = UINT_MAX;
620 		c->openmax = 0;
621 	}
622 	c->integer = 0;
623 }
624 
625 #undef assert
626 /* ---- */
627 
628 
629 /**
630  * snd_interval_ratnum - refine the interval value
631  * @i: interval to refine
632  * @rats_count: number of ratnum_t
633  * @rats: ratnum_t array
634  * @nump: pointer to store the resultant numerator
635  * @denp: pointer to store the resultant denominator
636  *
637  * Returns non-zero if the value is changed, zero if not changed.
638  */
639 int snd_interval_ratnum(snd_interval_t *i,
640 		    unsigned int rats_count, ratnum_t *rats,
641 		    unsigned int *nump, unsigned int *denp)
642 {
643 	unsigned int best_num, best_diff, best_den;
644 	unsigned int k;
645 	snd_interval_t t;
646 	int err;
647 
648 	best_num = best_den = best_diff = 0;
649 	for (k = 0; k < rats_count; ++k) {
650 		unsigned int num = rats[k].num;
651 		unsigned int den;
652 		unsigned int q = i->min;
653 		int diff;
654 		if (q == 0)
655 			q = 1;
656 		den = div_down(num, q);
657 		if (den < rats[k].den_min)
658 			continue;
659 		if (den > rats[k].den_max)
660 			den = rats[k].den_max;
661 		else {
662 			unsigned int r;
663 			r = (den - rats[k].den_min) % rats[k].den_step;
664 			if (r != 0)
665 				den -= r;
666 		}
667 		diff = num - q * den;
668 		if (best_num == 0 ||
669 		    diff * best_den < best_diff * den) {
670 			best_diff = diff;
671 			best_den = den;
672 			best_num = num;
673 		}
674 	}
675 	if (best_den == 0) {
676 		i->empty = 1;
677 		return -EINVAL;
678 	}
679 	t.min = div_down(best_num, best_den);
680 	t.openmin = !!(best_num % best_den);
681 
682 	best_num = best_den = best_diff = 0;
683 	for (k = 0; k < rats_count; ++k) {
684 		unsigned int num = rats[k].num;
685 		unsigned int den;
686 		unsigned int q = i->max;
687 		int diff;
688 		if (q == 0) {
689 			i->empty = 1;
690 			return -EINVAL;
691 		}
692 		den = div_up(num, q);
693 		if (den > rats[k].den_max)
694 			continue;
695 		if (den < rats[k].den_min)
696 			den = rats[k].den_min;
697 		else {
698 			unsigned int r;
699 			r = (den - rats[k].den_min) % rats[k].den_step;
700 			if (r != 0)
701 				den += rats[k].den_step - r;
702 		}
703 		diff = q * den - num;
704 		if (best_num == 0 ||
705 		    diff * best_den < best_diff * den) {
706 			best_diff = diff;
707 			best_den = den;
708 			best_num = num;
709 		}
710 	}
711 	if (best_den == 0) {
712 		i->empty = 1;
713 		return -EINVAL;
714 	}
715 	t.max = div_up(best_num, best_den);
716 	t.openmax = !!(best_num % best_den);
717 	t.integer = 0;
718 	err = snd_interval_refine(i, &t);
719 	if (err < 0)
720 		return err;
721 
722 	if (snd_interval_single(i)) {
723 		if (nump)
724 			*nump = best_num;
725 		if (denp)
726 			*denp = best_den;
727 	}
728 	return err;
729 }
730 
731 /**
732  * snd_interval_ratden - refine the interval value
733  * @i: interval to refine
734  * @rats_count: number of ratden_t
735  * @rats: ratden_t array
736  * @nump: pointer to store the resultant numerator
737  * @denp: pointer to store the resultant denominator
738  *
739  * Returns non-zero if the value is changed, zero if not changed.
740  */
741 static int snd_interval_ratden(snd_interval_t *i,
742 			       unsigned int rats_count, ratden_t *rats,
743 			       unsigned int *nump, unsigned int *denp)
744 {
745 	unsigned int best_num, best_diff, best_den;
746 	unsigned int k;
747 	snd_interval_t t;
748 	int err;
749 
750 	best_num = best_den = best_diff = 0;
751 	for (k = 0; k < rats_count; ++k) {
752 		unsigned int num;
753 		unsigned int den = rats[k].den;
754 		unsigned int q = i->min;
755 		int diff;
756 		num = mul(q, den);
757 		if (num > rats[k].num_max)
758 			continue;
759 		if (num < rats[k].num_min)
760 			num = rats[k].num_max;
761 		else {
762 			unsigned int r;
763 			r = (num - rats[k].num_min) % rats[k].num_step;
764 			if (r != 0)
765 				num += rats[k].num_step - r;
766 		}
767 		diff = num - q * den;
768 		if (best_num == 0 ||
769 		    diff * best_den < best_diff * den) {
770 			best_diff = diff;
771 			best_den = den;
772 			best_num = num;
773 		}
774 	}
775 	if (best_den == 0) {
776 		i->empty = 1;
777 		return -EINVAL;
778 	}
779 	t.min = div_down(best_num, best_den);
780 	t.openmin = !!(best_num % best_den);
781 
782 	best_num = best_den = best_diff = 0;
783 	for (k = 0; k < rats_count; ++k) {
784 		unsigned int num;
785 		unsigned int den = rats[k].den;
786 		unsigned int q = i->max;
787 		int diff;
788 		num = mul(q, den);
789 		if (num < rats[k].num_min)
790 			continue;
791 		if (num > rats[k].num_max)
792 			num = rats[k].num_max;
793 		else {
794 			unsigned int r;
795 			r = (num - rats[k].num_min) % rats[k].num_step;
796 			if (r != 0)
797 				num -= r;
798 		}
799 		diff = q * den - num;
800 		if (best_num == 0 ||
801 		    diff * best_den < best_diff * den) {
802 			best_diff = diff;
803 			best_den = den;
804 			best_num = num;
805 		}
806 	}
807 	if (best_den == 0) {
808 		i->empty = 1;
809 		return -EINVAL;
810 	}
811 	t.max = div_up(best_num, best_den);
812 	t.openmax = !!(best_num % best_den);
813 	t.integer = 0;
814 	err = snd_interval_refine(i, &t);
815 	if (err < 0)
816 		return err;
817 
818 	if (snd_interval_single(i)) {
819 		if (nump)
820 			*nump = best_num;
821 		if (denp)
822 			*denp = best_den;
823 	}
824 	return err;
825 }
826 
827 /**
828  * snd_interval_list - refine the interval value from the list
829  * @i: the interval value to refine
830  * @count: the number of elements in the list
831  * @list: the value list
832  * @mask: the bit-mask to evaluate
833  *
834  * Refines the interval value from the list.
835  * When mask is non-zero, only the elements corresponding to bit 1 are
836  * evaluated.
837  *
838  * Returns non-zero if the value is changed, zero if not changed.
839  */
840 int snd_interval_list(snd_interval_t *i, unsigned int count, unsigned int *list, unsigned int mask)
841 {
842         unsigned int k;
843 	int changed = 0;
844         for (k = 0; k < count; k++) {
845 		if (mask && !(mask & (1 << k)))
846 			continue;
847                 if (i->min == list[k] && !i->openmin)
848                         goto _l1;
849                 if (i->min < list[k]) {
850                         i->min = list[k];
851 			i->openmin = 0;
852 			changed = 1;
853                         goto _l1;
854                 }
855         }
856         i->empty = 1;
857         return -EINVAL;
858  _l1:
859         for (k = count; k-- > 0;) {
860 		if (mask && !(mask & (1 << k)))
861 			continue;
862                 if (i->max == list[k] && !i->openmax)
863                         goto _l2;
864                 if (i->max > list[k]) {
865                         i->max = list[k];
866 			i->openmax = 0;
867 			changed = 1;
868                         goto _l2;
869                 }
870         }
871         i->empty = 1;
872         return -EINVAL;
873  _l2:
874 	if (snd_interval_checkempty(i)) {
875 		i->empty = 1;
876 		return -EINVAL;
877 	}
878         return changed;
879 }
880 
881 static int snd_interval_step(snd_interval_t *i, unsigned int min, unsigned int step)
882 {
883 	unsigned int n;
884 	int changed = 0;
885 	n = (i->min - min) % step;
886 	if (n != 0 || i->openmin) {
887 		i->min += step - n;
888 		changed = 1;
889 	}
890 	n = (i->max - min) % step;
891 	if (n != 0 || i->openmax) {
892 		i->max -= n;
893 		changed = 1;
894 	}
895 	if (snd_interval_checkempty(i)) {
896 		i->empty = 1;
897 		return -EINVAL;
898 	}
899 	return changed;
900 }
901 
902 /* Info constraints helpers */
903 
904 /**
905  * snd_pcm_hw_rule_add - add the hw-constraint rule
906  * @runtime: the pcm runtime instance
907  * @cond: condition bits
908  * @var: the variable to evaluate
909  * @func: the evaluation function
910  * @private: the private data pointer passed to function
911  * @dep: the dependent variables
912  *
913  * Returns zero if successful, or a negative error code on failure.
914  */
915 int snd_pcm_hw_rule_add(snd_pcm_runtime_t *runtime, unsigned int cond,
916 			int var,
917 			snd_pcm_hw_rule_func_t func, void *private,
918 			int dep, ...)
919 {
920 	snd_pcm_hw_constraints_t *constrs = &runtime->hw_constraints;
921 	snd_pcm_hw_rule_t *c;
922 	unsigned int k;
923 	va_list args;
924 	va_start(args, dep);
925 	if (constrs->rules_num >= constrs->rules_all) {
926 		snd_pcm_hw_rule_t *new;
927 		unsigned int new_rules = constrs->rules_all + 16;
928 		new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
929 		if (!new)
930 			return -ENOMEM;
931 		if (constrs->rules) {
932 			memcpy(new, constrs->rules,
933 			       constrs->rules_num * sizeof(*c));
934 			kfree(constrs->rules);
935 		}
936 		constrs->rules = new;
937 		constrs->rules_all = new_rules;
938 	}
939 	c = &constrs->rules[constrs->rules_num];
940 	c->cond = cond;
941 	c->func = func;
942 	c->var = var;
943 	c->private = private;
944 	k = 0;
945 	while (1) {
946 		snd_assert(k < ARRAY_SIZE(c->deps), return -EINVAL);
947 		c->deps[k++] = dep;
948 		if (dep < 0)
949 			break;
950 		dep = va_arg(args, int);
951 	}
952 	constrs->rules_num++;
953 	va_end(args);
954 	return 0;
955 }
956 
957 /**
958  * snd_pcm_hw_constraint_mask
959  * @runtime: PCM runtime instance
960  * @var: hw_params variable to apply the mask
961  * @mask: the bitmap mask
962  *
963  * Apply the constraint of the given bitmap mask to a mask parameter.
964  */
965 int snd_pcm_hw_constraint_mask(snd_pcm_runtime_t *runtime, snd_pcm_hw_param_t var,
966 			       u_int32_t mask)
967 {
968 	snd_pcm_hw_constraints_t *constrs = &runtime->hw_constraints;
969 	snd_mask_t *maskp = constrs_mask(constrs, var);
970 	*maskp->bits &= mask;
971 	memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
972 	if (*maskp->bits == 0)
973 		return -EINVAL;
974 	return 0;
975 }
976 
977 /**
978  * snd_pcm_hw_constraint_mask64
979  * @runtime: PCM runtime instance
980  * @var: hw_params variable to apply the mask
981  * @mask: the 64bit bitmap mask
982  *
983  * Apply the constraint of the given bitmap mask to a mask parameter.
984  */
985 int snd_pcm_hw_constraint_mask64(snd_pcm_runtime_t *runtime, snd_pcm_hw_param_t var,
986 				 u_int64_t mask)
987 {
988 	snd_pcm_hw_constraints_t *constrs = &runtime->hw_constraints;
989 	snd_mask_t *maskp = constrs_mask(constrs, var);
990 	maskp->bits[0] &= (u_int32_t)mask;
991 	maskp->bits[1] &= (u_int32_t)(mask >> 32);
992 	memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
993 	if (! maskp->bits[0] && ! maskp->bits[1])
994 		return -EINVAL;
995 	return 0;
996 }
997 
998 /**
999  * snd_pcm_hw_constraint_integer
1000  * @runtime: PCM runtime instance
1001  * @var: hw_params variable to apply the integer constraint
1002  *
1003  * Apply the constraint of integer to an interval parameter.
1004  */
1005 int snd_pcm_hw_constraint_integer(snd_pcm_runtime_t *runtime, snd_pcm_hw_param_t var)
1006 {
1007 	snd_pcm_hw_constraints_t *constrs = &runtime->hw_constraints;
1008 	return snd_interval_setinteger(constrs_interval(constrs, var));
1009 }
1010 
1011 /**
1012  * snd_pcm_hw_constraint_minmax
1013  * @runtime: PCM runtime instance
1014  * @var: hw_params variable to apply the range
1015  * @min: the minimal value
1016  * @max: the maximal value
1017  *
1018  * Apply the min/max range constraint to an interval parameter.
1019  */
1020 int snd_pcm_hw_constraint_minmax(snd_pcm_runtime_t *runtime, snd_pcm_hw_param_t var,
1021 				 unsigned int min, unsigned int max)
1022 {
1023 	snd_pcm_hw_constraints_t *constrs = &runtime->hw_constraints;
1024 	snd_interval_t t;
1025 	t.min = min;
1026 	t.max = max;
1027 	t.openmin = t.openmax = 0;
1028 	t.integer = 0;
1029 	return snd_interval_refine(constrs_interval(constrs, var), &t);
1030 }
1031 
1032 static int snd_pcm_hw_rule_list(snd_pcm_hw_params_t *params,
1033 				snd_pcm_hw_rule_t *rule)
1034 {
1035 	snd_pcm_hw_constraint_list_t *list = rule->private;
1036 	return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1037 }
1038 
1039 
1040 /**
1041  * snd_pcm_hw_constraint_list
1042  * @runtime: PCM runtime instance
1043  * @cond: condition bits
1044  * @var: hw_params variable to apply the list constraint
1045  * @l: list
1046  *
1047  * Apply the list of constraints to an interval parameter.
1048  */
1049 int snd_pcm_hw_constraint_list(snd_pcm_runtime_t *runtime,
1050 			       unsigned int cond,
1051 			       snd_pcm_hw_param_t var,
1052 			       snd_pcm_hw_constraint_list_t *l)
1053 {
1054 	return snd_pcm_hw_rule_add(runtime, cond, var,
1055 				   snd_pcm_hw_rule_list, l,
1056 				   var, -1);
1057 }
1058 
1059 static int snd_pcm_hw_rule_ratnums(snd_pcm_hw_params_t *params,
1060 				   snd_pcm_hw_rule_t *rule)
1061 {
1062 	snd_pcm_hw_constraint_ratnums_t *r = rule->private;
1063 	unsigned int num = 0, den = 0;
1064 	int err;
1065 	err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1066 				  r->nrats, r->rats, &num, &den);
1067 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1068 		params->rate_num = num;
1069 		params->rate_den = den;
1070 	}
1071 	return err;
1072 }
1073 
1074 /**
1075  * snd_pcm_hw_constraint_ratnums
1076  * @runtime: PCM runtime instance
1077  * @cond: condition bits
1078  * @var: hw_params variable to apply the ratnums constraint
1079  * @r: ratnums_t constriants
1080  */
1081 int snd_pcm_hw_constraint_ratnums(snd_pcm_runtime_t *runtime,
1082 				  unsigned int cond,
1083 				  snd_pcm_hw_param_t var,
1084 				  snd_pcm_hw_constraint_ratnums_t *r)
1085 {
1086 	return snd_pcm_hw_rule_add(runtime, cond, var,
1087 				   snd_pcm_hw_rule_ratnums, r,
1088 				   var, -1);
1089 }
1090 
1091 static int snd_pcm_hw_rule_ratdens(snd_pcm_hw_params_t *params,
1092 				   snd_pcm_hw_rule_t *rule)
1093 {
1094 	snd_pcm_hw_constraint_ratdens_t *r = rule->private;
1095 	unsigned int num = 0, den = 0;
1096 	int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1097 				  r->nrats, r->rats, &num, &den);
1098 	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1099 		params->rate_num = num;
1100 		params->rate_den = den;
1101 	}
1102 	return err;
1103 }
1104 
1105 /**
1106  * snd_pcm_hw_constraint_ratdens
1107  * @runtime: PCM runtime instance
1108  * @cond: condition bits
1109  * @var: hw_params variable to apply the ratdens constraint
1110  * @r: ratdens_t constriants
1111  */
1112 int snd_pcm_hw_constraint_ratdens(snd_pcm_runtime_t *runtime,
1113 				  unsigned int cond,
1114 				  snd_pcm_hw_param_t var,
1115 				  snd_pcm_hw_constraint_ratdens_t *r)
1116 {
1117 	return snd_pcm_hw_rule_add(runtime, cond, var,
1118 				   snd_pcm_hw_rule_ratdens, r,
1119 				   var, -1);
1120 }
1121 
1122 static int snd_pcm_hw_rule_msbits(snd_pcm_hw_params_t *params,
1123 				  snd_pcm_hw_rule_t *rule)
1124 {
1125 	unsigned int l = (unsigned long) rule->private;
1126 	int width = l & 0xffff;
1127 	unsigned int msbits = l >> 16;
1128 	snd_interval_t *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1129 	if (snd_interval_single(i) && snd_interval_value(i) == width)
1130 		params->msbits = msbits;
1131 	return 0;
1132 }
1133 
1134 /**
1135  * snd_pcm_hw_constraint_msbits
1136  * @runtime: PCM runtime instance
1137  * @cond: condition bits
1138  * @width: sample bits width
1139  * @msbits: msbits width
1140  */
1141 int snd_pcm_hw_constraint_msbits(snd_pcm_runtime_t *runtime,
1142 				 unsigned int cond,
1143 				 unsigned int width,
1144 				 unsigned int msbits)
1145 {
1146 	unsigned long l = (msbits << 16) | width;
1147 	return snd_pcm_hw_rule_add(runtime, cond, -1,
1148 				    snd_pcm_hw_rule_msbits,
1149 				    (void*) l,
1150 				    SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1151 }
1152 
1153 static int snd_pcm_hw_rule_step(snd_pcm_hw_params_t *params,
1154 				snd_pcm_hw_rule_t *rule)
1155 {
1156 	unsigned long step = (unsigned long) rule->private;
1157 	return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1158 }
1159 
1160 /**
1161  * snd_pcm_hw_constraint_step
1162  * @runtime: PCM runtime instance
1163  * @cond: condition bits
1164  * @var: hw_params variable to apply the step constraint
1165  * @step: step size
1166  */
1167 int snd_pcm_hw_constraint_step(snd_pcm_runtime_t *runtime,
1168 			       unsigned int cond,
1169 			       snd_pcm_hw_param_t var,
1170 			       unsigned long step)
1171 {
1172 	return snd_pcm_hw_rule_add(runtime, cond, var,
1173 				   snd_pcm_hw_rule_step, (void *) step,
1174 				   var, -1);
1175 }
1176 
1177 static int snd_pcm_hw_rule_pow2(snd_pcm_hw_params_t *params, snd_pcm_hw_rule_t *rule)
1178 {
1179 	static int pow2_sizes[] = {
1180 		1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1181 		1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1182 		1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1183 		1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1184 	};
1185 	return snd_interval_list(hw_param_interval(params, rule->var),
1186 				 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1187 }
1188 
1189 /**
1190  * snd_pcm_hw_constraint_pow2
1191  * @runtime: PCM runtime instance
1192  * @cond: condition bits
1193  * @var: hw_params variable to apply the power-of-2 constraint
1194  */
1195 int snd_pcm_hw_constraint_pow2(snd_pcm_runtime_t *runtime,
1196 			       unsigned int cond,
1197 			       snd_pcm_hw_param_t var)
1198 {
1199 	return snd_pcm_hw_rule_add(runtime, cond, var,
1200 				   snd_pcm_hw_rule_pow2, NULL,
1201 				   var, -1);
1202 }
1203 
1204 /* To use the same code we have in alsa-lib */
1205 #define snd_pcm_t snd_pcm_substream_t
1206 #define assert(i) snd_assert((i), return -EINVAL)
1207 #ifndef INT_MIN
1208 #define INT_MIN ((int)((unsigned int)INT_MAX+1))
1209 #endif
1210 
1211 static void _snd_pcm_hw_param_any(snd_pcm_hw_params_t *params,
1212 				  snd_pcm_hw_param_t var)
1213 {
1214 	if (hw_is_mask(var)) {
1215 		snd_mask_any(hw_param_mask(params, var));
1216 		params->cmask |= 1 << var;
1217 		params->rmask |= 1 << var;
1218 		return;
1219 	}
1220 	if (hw_is_interval(var)) {
1221 		snd_interval_any(hw_param_interval(params, var));
1222 		params->cmask |= 1 << var;
1223 		params->rmask |= 1 << var;
1224 		return;
1225 	}
1226 	snd_BUG();
1227 }
1228 
1229 #if 0
1230 /*
1231  * snd_pcm_hw_param_any
1232  */
1233 int snd_pcm_hw_param_any(snd_pcm_t *pcm, snd_pcm_hw_params_t *params,
1234 			 snd_pcm_hw_param_t var)
1235 {
1236 	_snd_pcm_hw_param_any(params, var);
1237 	return snd_pcm_hw_refine(pcm, params);
1238 }
1239 #endif  /*  0  */
1240 
1241 void _snd_pcm_hw_params_any(snd_pcm_hw_params_t *params)
1242 {
1243 	unsigned int k;
1244 	memset(params, 0, sizeof(*params));
1245 	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1246 		_snd_pcm_hw_param_any(params, k);
1247 	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1248 		_snd_pcm_hw_param_any(params, k);
1249 	params->info = ~0U;
1250 }
1251 
1252 #if 0
1253 /*
1254  * snd_pcm_hw_params_any
1255  *
1256  * Fill PARAMS with full configuration space boundaries
1257  */
1258 int snd_pcm_hw_params_any(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
1259 {
1260 	_snd_pcm_hw_params_any(params);
1261 	return snd_pcm_hw_refine(pcm, params);
1262 }
1263 #endif  /*  0  */
1264 
1265 /**
1266  * snd_pcm_hw_param_value
1267  * @params: the hw_params instance
1268  * @var: parameter to retrieve
1269  * @dir: pointer to the direction (-1,0,1) or NULL
1270  *
1271  * Return the value for field PAR if it's fixed in configuration space
1272  *  defined by PARAMS. Return -EINVAL otherwise
1273  */
1274 static int snd_pcm_hw_param_value(const snd_pcm_hw_params_t *params,
1275 				  snd_pcm_hw_param_t var, int *dir)
1276 {
1277 	if (hw_is_mask(var)) {
1278 		const snd_mask_t *mask = hw_param_mask_c(params, var);
1279 		if (!snd_mask_single(mask))
1280 			return -EINVAL;
1281 		if (dir)
1282 			*dir = 0;
1283 		return snd_mask_value(mask);
1284 	}
1285 	if (hw_is_interval(var)) {
1286 		const snd_interval_t *i = hw_param_interval_c(params, var);
1287 		if (!snd_interval_single(i))
1288 			return -EINVAL;
1289 		if (dir)
1290 			*dir = i->openmin;
1291 		return snd_interval_value(i);
1292 	}
1293 	assert(0);
1294 	return -EINVAL;
1295 }
1296 
1297 /**
1298  * snd_pcm_hw_param_value_min
1299  * @params: the hw_params instance
1300  * @var: parameter to retrieve
1301  * @dir: pointer to the direction (-1,0,1) or NULL
1302  *
1303  * Return the minimum value for field PAR.
1304  */
1305 unsigned int snd_pcm_hw_param_value_min(const snd_pcm_hw_params_t *params,
1306 					snd_pcm_hw_param_t var, int *dir)
1307 {
1308 	if (hw_is_mask(var)) {
1309 		if (dir)
1310 			*dir = 0;
1311 		return snd_mask_min(hw_param_mask_c(params, var));
1312 	}
1313 	if (hw_is_interval(var)) {
1314 		const snd_interval_t *i = hw_param_interval_c(params, var);
1315 		if (dir)
1316 			*dir = i->openmin;
1317 		return snd_interval_min(i);
1318 	}
1319 	assert(0);
1320 	return -EINVAL;
1321 }
1322 
1323 /**
1324  * snd_pcm_hw_param_value_max
1325  * @params: the hw_params instance
1326  * @var: parameter to retrieve
1327  * @dir: pointer to the direction (-1,0,1) or NULL
1328  *
1329  * Return the maximum value for field PAR.
1330  */
1331 unsigned int snd_pcm_hw_param_value_max(const snd_pcm_hw_params_t *params,
1332 					snd_pcm_hw_param_t var, int *dir)
1333 {
1334 	if (hw_is_mask(var)) {
1335 		if (dir)
1336 			*dir = 0;
1337 		return snd_mask_max(hw_param_mask_c(params, var));
1338 	}
1339 	if (hw_is_interval(var)) {
1340 		const snd_interval_t *i = hw_param_interval_c(params, var);
1341 		if (dir)
1342 			*dir = - (int) i->openmax;
1343 		return snd_interval_max(i);
1344 	}
1345 	assert(0);
1346 	return -EINVAL;
1347 }
1348 
1349 void _snd_pcm_hw_param_setempty(snd_pcm_hw_params_t *params,
1350 				snd_pcm_hw_param_t var)
1351 {
1352 	if (hw_is_mask(var)) {
1353 		snd_mask_none(hw_param_mask(params, var));
1354 		params->cmask |= 1 << var;
1355 		params->rmask |= 1 << var;
1356 	} else if (hw_is_interval(var)) {
1357 		snd_interval_none(hw_param_interval(params, var));
1358 		params->cmask |= 1 << var;
1359 		params->rmask |= 1 << var;
1360 	} else {
1361 		snd_BUG();
1362 	}
1363 }
1364 
1365 int _snd_pcm_hw_param_setinteger(snd_pcm_hw_params_t *params,
1366 				 snd_pcm_hw_param_t var)
1367 {
1368 	int changed;
1369 	assert(hw_is_interval(var));
1370 	changed = snd_interval_setinteger(hw_param_interval(params, var));
1371 	if (changed) {
1372 		params->cmask |= 1 << var;
1373 		params->rmask |= 1 << var;
1374 	}
1375 	return changed;
1376 }
1377 
1378 #if 0
1379 /*
1380  * snd_pcm_hw_param_setinteger
1381  *
1382  * Inside configuration space defined by PARAMS remove from PAR all
1383  * non integer values. Reduce configuration space accordingly.
1384  * Return -EINVAL if the configuration space is empty
1385  */
1386 int snd_pcm_hw_param_setinteger(snd_pcm_t *pcm,
1387 				snd_pcm_hw_params_t *params,
1388 				snd_pcm_hw_param_t var)
1389 {
1390 	int changed = _snd_pcm_hw_param_setinteger(params, var);
1391 	if (changed < 0)
1392 		return changed;
1393 	if (params->rmask) {
1394 		int err = snd_pcm_hw_refine(pcm, params);
1395 		if (err < 0)
1396 			return err;
1397 	}
1398 	return 0;
1399 }
1400 #endif  /*  0  */
1401 
1402 static int _snd_pcm_hw_param_first(snd_pcm_hw_params_t *params,
1403 				   snd_pcm_hw_param_t var)
1404 {
1405 	int changed;
1406 	if (hw_is_mask(var))
1407 		changed = snd_mask_refine_first(hw_param_mask(params, var));
1408 	else if (hw_is_interval(var))
1409 		changed = snd_interval_refine_first(hw_param_interval(params, var));
1410 	else {
1411 		assert(0);
1412 		return -EINVAL;
1413 	}
1414 	if (changed) {
1415 		params->cmask |= 1 << var;
1416 		params->rmask |= 1 << var;
1417 	}
1418 	return changed;
1419 }
1420 
1421 
1422 /**
1423  * snd_pcm_hw_param_first
1424  * @pcm: PCM instance
1425  * @params: the hw_params instance
1426  * @var: parameter to retrieve
1427  * @dir: pointer to the direction (-1,0,1) or NULL
1428  *
1429  * Inside configuration space defined by PARAMS remove from PAR all
1430  * values > minimum. Reduce configuration space accordingly.
1431  * Return the minimum.
1432  */
1433 static int snd_pcm_hw_param_first(snd_pcm_t *pcm,
1434 				  snd_pcm_hw_params_t *params,
1435 				  snd_pcm_hw_param_t var, int *dir)
1436 {
1437 	int changed = _snd_pcm_hw_param_first(params, var);
1438 	if (changed < 0)
1439 		return changed;
1440 	if (params->rmask) {
1441 		int err = snd_pcm_hw_refine(pcm, params);
1442 		assert(err >= 0);
1443 	}
1444 	return snd_pcm_hw_param_value(params, var, dir);
1445 }
1446 
1447 static int _snd_pcm_hw_param_last(snd_pcm_hw_params_t *params,
1448 				  snd_pcm_hw_param_t var)
1449 {
1450 	int changed;
1451 	if (hw_is_mask(var))
1452 		changed = snd_mask_refine_last(hw_param_mask(params, var));
1453 	else if (hw_is_interval(var))
1454 		changed = snd_interval_refine_last(hw_param_interval(params, var));
1455 	else {
1456 		assert(0);
1457 		return -EINVAL;
1458 	}
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_last
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 PAR all
1475  * values < maximum. Reduce configuration space accordingly.
1476  * Return the maximum.
1477  */
1478 static int snd_pcm_hw_param_last(snd_pcm_t *pcm,
1479 				 snd_pcm_hw_params_t *params,
1480 				 snd_pcm_hw_param_t var, int *dir)
1481 {
1482 	int changed = _snd_pcm_hw_param_last(params, var);
1483 	if (changed < 0)
1484 		return changed;
1485 	if (params->rmask) {
1486 		int err = snd_pcm_hw_refine(pcm, params);
1487 		assert(err >= 0);
1488 	}
1489 	return snd_pcm_hw_param_value(params, var, dir);
1490 }
1491 
1492 int _snd_pcm_hw_param_min(snd_pcm_hw_params_t *params,
1493 			  snd_pcm_hw_param_t var, unsigned int val, int dir)
1494 {
1495 	int changed;
1496 	int open = 0;
1497 	if (dir) {
1498 		if (dir > 0) {
1499 			open = 1;
1500 		} else if (dir < 0) {
1501 			if (val > 0) {
1502 				open = 1;
1503 				val--;
1504 			}
1505 		}
1506 	}
1507 	if (hw_is_mask(var))
1508 		changed = snd_mask_refine_min(hw_param_mask(params, var), val + !!open);
1509 	else if (hw_is_interval(var))
1510 		changed = snd_interval_refine_min(hw_param_interval(params, var), val, open);
1511 	else {
1512 		assert(0);
1513 		return -EINVAL;
1514 	}
1515 	if (changed) {
1516 		params->cmask |= 1 << var;
1517 		params->rmask |= 1 << var;
1518 	}
1519 	return changed;
1520 }
1521 
1522 /**
1523  * snd_pcm_hw_param_min
1524  * @pcm: PCM instance
1525  * @params: the hw_params instance
1526  * @var: parameter to retrieve
1527  * @val: minimal value
1528  * @dir: pointer to the direction (-1,0,1) or NULL
1529  *
1530  * Inside configuration space defined by PARAMS remove from PAR all
1531  * values < VAL. Reduce configuration space accordingly.
1532  * Return new minimum or -EINVAL if the configuration space is empty
1533  */
1534 static int snd_pcm_hw_param_min(snd_pcm_t *pcm, snd_pcm_hw_params_t *params,
1535 				snd_pcm_hw_param_t var, unsigned int val,
1536 				int *dir)
1537 {
1538 	int changed = _snd_pcm_hw_param_min(params, var, val, dir ? *dir : 0);
1539 	if (changed < 0)
1540 		return changed;
1541 	if (params->rmask) {
1542 		int err = snd_pcm_hw_refine(pcm, params);
1543 		if (err < 0)
1544 			return err;
1545 	}
1546 	return snd_pcm_hw_param_value_min(params, var, dir);
1547 }
1548 
1549 static int _snd_pcm_hw_param_max(snd_pcm_hw_params_t *params,
1550 				 snd_pcm_hw_param_t var, unsigned int val,
1551 				 int dir)
1552 {
1553 	int changed;
1554 	int open = 0;
1555 	if (dir) {
1556 		if (dir < 0) {
1557 			open = 1;
1558 		} else if (dir > 0) {
1559 			open = 1;
1560 			val++;
1561 		}
1562 	}
1563 	if (hw_is_mask(var)) {
1564 		if (val == 0 && open) {
1565 			snd_mask_none(hw_param_mask(params, var));
1566 			changed = -EINVAL;
1567 		} else
1568 			changed = snd_mask_refine_max(hw_param_mask(params, var), val - !!open);
1569 	} else if (hw_is_interval(var))
1570 		changed = snd_interval_refine_max(hw_param_interval(params, var), val, open);
1571 	else {
1572 		assert(0);
1573 		return -EINVAL;
1574 	}
1575 	if (changed) {
1576 		params->cmask |= 1 << var;
1577 		params->rmask |= 1 << var;
1578 	}
1579 	return changed;
1580 }
1581 
1582 /**
1583  * snd_pcm_hw_param_max
1584  * @pcm: PCM instance
1585  * @params: the hw_params instance
1586  * @var: parameter to retrieve
1587  * @val: maximal value
1588  * @dir: pointer to the direction (-1,0,1) or NULL
1589  *
1590  * Inside configuration space defined by PARAMS remove from PAR all
1591  *  values >= VAL + 1. Reduce configuration space accordingly.
1592  *  Return new maximum or -EINVAL if the configuration space is empty
1593  */
1594 static int snd_pcm_hw_param_max(snd_pcm_t *pcm, snd_pcm_hw_params_t *params,
1595 				snd_pcm_hw_param_t var, unsigned int val,
1596 				int *dir)
1597 {
1598 	int changed = _snd_pcm_hw_param_max(params, var, val, dir ? *dir : 0);
1599 	if (changed < 0)
1600 		return changed;
1601 	if (params->rmask) {
1602 		int err = snd_pcm_hw_refine(pcm, params);
1603 		if (err < 0)
1604 			return err;
1605 	}
1606 	return snd_pcm_hw_param_value_max(params, var, dir);
1607 }
1608 
1609 int _snd_pcm_hw_param_set(snd_pcm_hw_params_t *params,
1610 			  snd_pcm_hw_param_t var, unsigned int val, int dir)
1611 {
1612 	int changed;
1613 	if (hw_is_mask(var)) {
1614 		snd_mask_t *m = hw_param_mask(params, var);
1615 		if (val == 0 && dir < 0) {
1616 			changed = -EINVAL;
1617 			snd_mask_none(m);
1618 		} else {
1619 			if (dir > 0)
1620 				val++;
1621 			else if (dir < 0)
1622 				val--;
1623 			changed = snd_mask_refine_set(hw_param_mask(params, var), val);
1624 		}
1625 	} else if (hw_is_interval(var)) {
1626 		snd_interval_t *i = hw_param_interval(params, var);
1627 		if (val == 0 && dir < 0) {
1628 			changed = -EINVAL;
1629 			snd_interval_none(i);
1630 		} else if (dir == 0)
1631 			changed = snd_interval_refine_set(i, val);
1632 		else {
1633 			snd_interval_t t;
1634 			t.openmin = 1;
1635 			t.openmax = 1;
1636 			t.empty = 0;
1637 			t.integer = 0;
1638 			if (dir < 0) {
1639 				t.min = val - 1;
1640 				t.max = val;
1641 			} else {
1642 				t.min = val;
1643 				t.max = val+1;
1644 			}
1645 			changed = snd_interval_refine(i, &t);
1646 		}
1647 	} else {
1648 		assert(0);
1649 		return -EINVAL;
1650 	}
1651 	if (changed) {
1652 		params->cmask |= 1 << var;
1653 		params->rmask |= 1 << var;
1654 	}
1655 	return changed;
1656 }
1657 
1658 /**
1659  * snd_pcm_hw_param_set
1660  * @pcm: PCM instance
1661  * @params: the hw_params instance
1662  * @var: parameter to retrieve
1663  * @val: value to set
1664  * @dir: pointer to the direction (-1,0,1) or NULL
1665  *
1666  * Inside configuration space defined by PARAMS remove from PAR all
1667  * values != VAL. Reduce configuration space accordingly.
1668  *  Return VAL or -EINVAL if the configuration space is empty
1669  */
1670 int snd_pcm_hw_param_set(snd_pcm_t *pcm, snd_pcm_hw_params_t *params,
1671 			 snd_pcm_hw_param_t var, unsigned int val, int dir)
1672 {
1673 	int changed = _snd_pcm_hw_param_set(params, var, val, dir);
1674 	if (changed < 0)
1675 		return changed;
1676 	if (params->rmask) {
1677 		int err = snd_pcm_hw_refine(pcm, params);
1678 		if (err < 0)
1679 			return err;
1680 	}
1681 	return snd_pcm_hw_param_value(params, var, NULL);
1682 }
1683 
1684 static int _snd_pcm_hw_param_mask(snd_pcm_hw_params_t *params,
1685 				  snd_pcm_hw_param_t var, const snd_mask_t *val)
1686 {
1687 	int changed;
1688 	assert(hw_is_mask(var));
1689 	changed = snd_mask_refine(hw_param_mask(params, var), val);
1690 	if (changed) {
1691 		params->cmask |= 1 << var;
1692 		params->rmask |= 1 << var;
1693 	}
1694 	return changed;
1695 }
1696 
1697 /**
1698  * snd_pcm_hw_param_mask
1699  * @pcm: PCM instance
1700  * @params: the hw_params instance
1701  * @var: parameter to retrieve
1702  * @val: mask to apply
1703  *
1704  * Inside configuration space defined by PARAMS remove from PAR all values
1705  * not contained in MASK. Reduce configuration space accordingly.
1706  * This function can be called only for SNDRV_PCM_HW_PARAM_ACCESS,
1707  * SNDRV_PCM_HW_PARAM_FORMAT, SNDRV_PCM_HW_PARAM_SUBFORMAT.
1708  * Return 0 on success or -EINVAL
1709  * if the configuration space is empty
1710  */
1711 int snd_pcm_hw_param_mask(snd_pcm_t *pcm, snd_pcm_hw_params_t *params,
1712 			  snd_pcm_hw_param_t var, const snd_mask_t *val)
1713 {
1714 	int changed = _snd_pcm_hw_param_mask(params, var, val);
1715 	if (changed < 0)
1716 		return changed;
1717 	if (params->rmask) {
1718 		int err = snd_pcm_hw_refine(pcm, params);
1719 		if (err < 0)
1720 			return err;
1721 	}
1722 	return 0;
1723 }
1724 
1725 static int boundary_sub(int a, int adir,
1726 			int b, int bdir,
1727 			int *c, int *cdir)
1728 {
1729 	adir = adir < 0 ? -1 : (adir > 0 ? 1 : 0);
1730 	bdir = bdir < 0 ? -1 : (bdir > 0 ? 1 : 0);
1731 	*c = a - b;
1732 	*cdir = adir - bdir;
1733 	if (*cdir == -2) {
1734 		assert(*c > INT_MIN);
1735 		(*c)--;
1736 	} else if (*cdir == 2) {
1737 		assert(*c < INT_MAX);
1738 		(*c)++;
1739 	}
1740 	return 0;
1741 }
1742 
1743 static int boundary_lt(unsigned int a, int adir,
1744 		       unsigned int b, int bdir)
1745 {
1746 	assert(a > 0 || adir >= 0);
1747 	assert(b > 0 || bdir >= 0);
1748 	if (adir < 0) {
1749 		a--;
1750 		adir = 1;
1751 	} else if (adir > 0)
1752 		adir = 1;
1753 	if (bdir < 0) {
1754 		b--;
1755 		bdir = 1;
1756 	} else if (bdir > 0)
1757 		bdir = 1;
1758 	return a < b || (a == b && adir < bdir);
1759 }
1760 
1761 /* Return 1 if min is nearer to best than max */
1762 static int boundary_nearer(int min, int mindir,
1763 			   int best, int bestdir,
1764 			   int max, int maxdir)
1765 {
1766 	int dmin, dmindir;
1767 	int dmax, dmaxdir;
1768 	boundary_sub(best, bestdir, min, mindir, &dmin, &dmindir);
1769 	boundary_sub(max, maxdir, best, bestdir, &dmax, &dmaxdir);
1770 	return boundary_lt(dmin, dmindir, dmax, dmaxdir);
1771 }
1772 
1773 /**
1774  * snd_pcm_hw_param_near
1775  * @pcm: PCM instance
1776  * @params: the hw_params instance
1777  * @var: parameter to retrieve
1778  * @best: value to set
1779  * @dir: pointer to the direction (-1,0,1) or NULL
1780  *
1781  * Inside configuration space defined by PARAMS set PAR to the available value
1782  * nearest to VAL. Reduce configuration space accordingly.
1783  * This function cannot be called for SNDRV_PCM_HW_PARAM_ACCESS,
1784  * SNDRV_PCM_HW_PARAM_FORMAT, SNDRV_PCM_HW_PARAM_SUBFORMAT.
1785  * Return the value found.
1786   */
1787 int snd_pcm_hw_param_near(snd_pcm_t *pcm, snd_pcm_hw_params_t *params,
1788 			  snd_pcm_hw_param_t var, unsigned int best, int *dir)
1789 {
1790 	snd_pcm_hw_params_t *save = NULL;
1791 	int v;
1792 	unsigned int saved_min;
1793 	int last = 0;
1794 	int min, max;
1795 	int mindir, maxdir;
1796 	int valdir = dir ? *dir : 0;
1797 	/* FIXME */
1798 	if (best > INT_MAX)
1799 		best = INT_MAX;
1800 	min = max = best;
1801 	mindir = maxdir = valdir;
1802 	if (maxdir > 0)
1803 		maxdir = 0;
1804 	else if (maxdir == 0)
1805 		maxdir = -1;
1806 	else {
1807 		maxdir = 1;
1808 		max--;
1809 	}
1810 	save = kmalloc(sizeof(*save), GFP_KERNEL);
1811 	if (save == NULL)
1812 		return -ENOMEM;
1813 	*save = *params;
1814 	saved_min = min;
1815 	min = snd_pcm_hw_param_min(pcm, params, var, min, &mindir);
1816 	if (min >= 0) {
1817 		snd_pcm_hw_params_t *params1;
1818 		if (max < 0)
1819 			goto _end;
1820 		if ((unsigned int)min == saved_min && mindir == valdir)
1821 			goto _end;
1822 		params1 = kmalloc(sizeof(*params1), GFP_KERNEL);
1823 		if (params1 == NULL) {
1824 			kfree(save);
1825 			return -ENOMEM;
1826 		}
1827 		*params1 = *save;
1828 		max = snd_pcm_hw_param_max(pcm, params1, var, max, &maxdir);
1829 		if (max < 0) {
1830 			kfree(params1);
1831 			goto _end;
1832 		}
1833 		if (boundary_nearer(max, maxdir, best, valdir, min, mindir)) {
1834 			*params = *params1;
1835 			last = 1;
1836 		}
1837 		kfree(params1);
1838 	} else {
1839 		*params = *save;
1840 		max = snd_pcm_hw_param_max(pcm, params, var, max, &maxdir);
1841 		assert(max >= 0);
1842 		last = 1;
1843 	}
1844  _end:
1845  	kfree(save);
1846 	if (last)
1847 		v = snd_pcm_hw_param_last(pcm, params, var, dir);
1848 	else
1849 		v = snd_pcm_hw_param_first(pcm, params, var, dir);
1850 	assert(v >= 0);
1851 	return v;
1852 }
1853 
1854 /**
1855  * snd_pcm_hw_param_choose
1856  * @pcm: PCM instance
1857  * @params: the hw_params instance
1858  *
1859  * Choose one configuration from configuration space defined by PARAMS
1860  * The configuration chosen is that obtained fixing in this order:
1861  * first access, first format, first subformat, min channels,
1862  * min rate, min period time, max buffer size, min tick time
1863  */
1864 int snd_pcm_hw_params_choose(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
1865 {
1866 	int err;
1867 
1868 	err = snd_pcm_hw_param_first(pcm, params, SNDRV_PCM_HW_PARAM_ACCESS, NULL);
1869 	assert(err >= 0);
1870 
1871 	err = snd_pcm_hw_param_first(pcm, params, SNDRV_PCM_HW_PARAM_FORMAT, NULL);
1872 	assert(err >= 0);
1873 
1874 	err = snd_pcm_hw_param_first(pcm, params, SNDRV_PCM_HW_PARAM_SUBFORMAT, NULL);
1875 	assert(err >= 0);
1876 
1877 	err = snd_pcm_hw_param_first(pcm, params, SNDRV_PCM_HW_PARAM_CHANNELS, NULL);
1878 	assert(err >= 0);
1879 
1880 	err = snd_pcm_hw_param_first(pcm, params, SNDRV_PCM_HW_PARAM_RATE, NULL);
1881 	assert(err >= 0);
1882 
1883 	err = snd_pcm_hw_param_first(pcm, params, SNDRV_PCM_HW_PARAM_PERIOD_TIME, NULL);
1884 	assert(err >= 0);
1885 
1886 	err = snd_pcm_hw_param_last(pcm, params, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, NULL);
1887 	assert(err >= 0);
1888 
1889 	err = snd_pcm_hw_param_first(pcm, params, SNDRV_PCM_HW_PARAM_TICK_TIME, NULL);
1890 	assert(err >= 0);
1891 
1892 	return 0;
1893 }
1894 
1895 #undef snd_pcm_t
1896 #undef assert
1897 
1898 static int snd_pcm_lib_ioctl_reset(snd_pcm_substream_t *substream,
1899 				   void *arg)
1900 {
1901 	snd_pcm_runtime_t *runtime = substream->runtime;
1902 	unsigned long flags;
1903 	snd_pcm_stream_lock_irqsave(substream, flags);
1904 	if (snd_pcm_running(substream) &&
1905 	    snd_pcm_update_hw_ptr(substream) >= 0)
1906 		runtime->status->hw_ptr %= runtime->buffer_size;
1907 	else
1908 		runtime->status->hw_ptr = 0;
1909 	snd_pcm_stream_unlock_irqrestore(substream, flags);
1910 	return 0;
1911 }
1912 
1913 static int snd_pcm_lib_ioctl_channel_info(snd_pcm_substream_t *substream,
1914 					  void *arg)
1915 {
1916 	snd_pcm_channel_info_t *info = arg;
1917 	snd_pcm_runtime_t *runtime = substream->runtime;
1918 	int width;
1919 	if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1920 		info->offset = -1;
1921 		return 0;
1922 	}
1923 	width = snd_pcm_format_physical_width(runtime->format);
1924 	if (width < 0)
1925 		return width;
1926 	info->offset = 0;
1927 	switch (runtime->access) {
1928 	case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1929 	case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1930 		info->first = info->channel * width;
1931 		info->step = runtime->channels * width;
1932 		break;
1933 	case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1934 	case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1935 	{
1936 		size_t size = runtime->dma_bytes / runtime->channels;
1937 		info->first = info->channel * size * 8;
1938 		info->step = width;
1939 		break;
1940 	}
1941 	default:
1942 		snd_BUG();
1943 		break;
1944 	}
1945 	return 0;
1946 }
1947 
1948 /**
1949  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1950  * @substream: the pcm substream instance
1951  * @cmd: ioctl command
1952  * @arg: ioctl argument
1953  *
1954  * Processes the generic ioctl commands for PCM.
1955  * Can be passed as the ioctl callback for PCM ops.
1956  *
1957  * Returns zero if successful, or a negative error code on failure.
1958  */
1959 int snd_pcm_lib_ioctl(snd_pcm_substream_t *substream,
1960 		      unsigned int cmd, void *arg)
1961 {
1962 	switch (cmd) {
1963 	case SNDRV_PCM_IOCTL1_INFO:
1964 		return 0;
1965 	case SNDRV_PCM_IOCTL1_RESET:
1966 		return snd_pcm_lib_ioctl_reset(substream, arg);
1967 	case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1968 		return snd_pcm_lib_ioctl_channel_info(substream, arg);
1969 	}
1970 	return -ENXIO;
1971 }
1972 
1973 /*
1974  *  Conditions
1975  */
1976 
1977 static void snd_pcm_system_tick_set(snd_pcm_substream_t *substream,
1978 				    unsigned long ticks)
1979 {
1980 	snd_pcm_runtime_t *runtime = substream->runtime;
1981 	if (ticks == 0)
1982 		del_timer(&runtime->tick_timer);
1983 	else {
1984 		ticks += (1000000 / HZ) - 1;
1985 		ticks /= (1000000 / HZ);
1986 		mod_timer(&runtime->tick_timer, jiffies + ticks);
1987 	}
1988 }
1989 
1990 /* Temporary alias */
1991 void snd_pcm_tick_set(snd_pcm_substream_t *substream, unsigned long ticks)
1992 {
1993 	snd_pcm_system_tick_set(substream, ticks);
1994 }
1995 
1996 void snd_pcm_tick_prepare(snd_pcm_substream_t *substream)
1997 {
1998 	snd_pcm_runtime_t *runtime = substream->runtime;
1999 	snd_pcm_uframes_t frames = ULONG_MAX;
2000 	snd_pcm_uframes_t avail, dist;
2001 	unsigned int ticks;
2002 	u_int64_t n;
2003 	u_int32_t r;
2004 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
2005 		if (runtime->silence_size >= runtime->boundary) {
2006 			frames = 1;
2007 		} else if (runtime->silence_size > 0 &&
2008 			   runtime->silence_filled < runtime->buffer_size) {
2009 			snd_pcm_sframes_t noise_dist;
2010 			noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
2011 			snd_assert(noise_dist <= (snd_pcm_sframes_t)runtime->silence_threshold, );
2012 			frames = noise_dist - runtime->silence_threshold;
2013 		}
2014 		avail = snd_pcm_playback_avail(runtime);
2015 	} else {
2016 		avail = snd_pcm_capture_avail(runtime);
2017 	}
2018 	if (avail < runtime->control->avail_min) {
2019 		snd_pcm_sframes_t n = runtime->control->avail_min - avail;
2020 		if (n > 0 && frames > (snd_pcm_uframes_t)n)
2021 			frames = n;
2022 	}
2023 	if (avail < runtime->buffer_size) {
2024 		snd_pcm_sframes_t n = runtime->buffer_size - avail;
2025 		if (n > 0 && frames > (snd_pcm_uframes_t)n)
2026 			frames = n;
2027 	}
2028 	if (frames == ULONG_MAX) {
2029 		snd_pcm_tick_set(substream, 0);
2030 		return;
2031 	}
2032 	dist = runtime->status->hw_ptr - runtime->hw_ptr_base;
2033 	/* Distance to next interrupt */
2034 	dist = runtime->period_size - dist % runtime->period_size;
2035 	if (dist <= frames) {
2036 		snd_pcm_tick_set(substream, 0);
2037 		return;
2038 	}
2039 	/* the base time is us */
2040 	n = frames;
2041 	n *= 1000000;
2042 	div64_32(&n, runtime->tick_time * runtime->rate, &r);
2043 	ticks = n + (r > 0 ? 1 : 0);
2044 	if (ticks < runtime->sleep_min)
2045 		ticks = runtime->sleep_min;
2046 	snd_pcm_tick_set(substream, (unsigned long) ticks);
2047 }
2048 
2049 void snd_pcm_tick_elapsed(snd_pcm_substream_t *substream)
2050 {
2051 	snd_pcm_runtime_t *runtime;
2052 	unsigned long flags;
2053 
2054 	snd_assert(substream != NULL, return);
2055 	runtime = substream->runtime;
2056 	snd_assert(runtime != NULL, return);
2057 
2058 	snd_pcm_stream_lock_irqsave(substream, flags);
2059 	if (!snd_pcm_running(substream) ||
2060 	    snd_pcm_update_hw_ptr(substream) < 0)
2061 		goto _end;
2062 	if (runtime->sleep_min)
2063 		snd_pcm_tick_prepare(substream);
2064  _end:
2065 	snd_pcm_stream_unlock_irqrestore(substream, flags);
2066 }
2067 
2068 /**
2069  * snd_pcm_period_elapsed - update the pcm status for the next period
2070  * @substream: the pcm substream instance
2071  *
2072  * This function is called from the interrupt handler when the
2073  * PCM has processed the period size.  It will update the current
2074  * pointer, set up the tick, wake up sleepers, etc.
2075  *
2076  * Even if more than one periods have elapsed since the last call, you
2077  * have to call this only once.
2078  */
2079 void snd_pcm_period_elapsed(snd_pcm_substream_t *substream)
2080 {
2081 	snd_pcm_runtime_t *runtime;
2082 	unsigned long flags;
2083 
2084 	snd_assert(substream != NULL, return);
2085 	runtime = substream->runtime;
2086 	snd_assert(runtime != NULL, return);
2087 
2088 	if (runtime->transfer_ack_begin)
2089 		runtime->transfer_ack_begin(substream);
2090 
2091 	snd_pcm_stream_lock_irqsave(substream, flags);
2092 	if (!snd_pcm_running(substream) ||
2093 	    snd_pcm_update_hw_ptr_interrupt(substream) < 0)
2094 		goto _end;
2095 
2096 	if (substream->timer_running)
2097 		snd_timer_interrupt(substream->timer, 1);
2098 	if (runtime->sleep_min)
2099 		snd_pcm_tick_prepare(substream);
2100  _end:
2101 	snd_pcm_stream_unlock_irqrestore(substream, flags);
2102 	if (runtime->transfer_ack_end)
2103 		runtime->transfer_ack_end(substream);
2104 	kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
2105 }
2106 
2107 static int snd_pcm_lib_write_transfer(snd_pcm_substream_t *substream,
2108 				      unsigned int hwoff,
2109 				      unsigned long data, unsigned int off,
2110 				      snd_pcm_uframes_t frames)
2111 {
2112 	snd_pcm_runtime_t *runtime = substream->runtime;
2113 	int err;
2114 	char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2115 	if (substream->ops->copy) {
2116 		if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2117 			return err;
2118 	} else {
2119 		char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2120 		snd_assert(runtime->dma_area, return -EFAULT);
2121 		if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
2122 			return -EFAULT;
2123 	}
2124 	return 0;
2125 }
2126 
2127 typedef int (*transfer_f)(snd_pcm_substream_t *substream, unsigned int hwoff,
2128 			  unsigned long data, unsigned int off,
2129 			  snd_pcm_uframes_t size);
2130 
2131 static snd_pcm_sframes_t snd_pcm_lib_write1(snd_pcm_substream_t *substream,
2132 					    unsigned long data,
2133 					    snd_pcm_uframes_t size,
2134 					    int nonblock,
2135 					    transfer_f transfer)
2136 {
2137 	snd_pcm_runtime_t *runtime = substream->runtime;
2138 	snd_pcm_uframes_t xfer = 0;
2139 	snd_pcm_uframes_t offset = 0;
2140 	int err = 0;
2141 
2142 	if (size == 0)
2143 		return 0;
2144 	if (size > runtime->xfer_align)
2145 		size -= size % runtime->xfer_align;
2146 
2147 	snd_pcm_stream_lock_irq(substream);
2148 	switch (runtime->status->state) {
2149 	case SNDRV_PCM_STATE_PREPARED:
2150 	case SNDRV_PCM_STATE_RUNNING:
2151 	case SNDRV_PCM_STATE_PAUSED:
2152 		break;
2153 	case SNDRV_PCM_STATE_XRUN:
2154 		err = -EPIPE;
2155 		goto _end_unlock;
2156 	case SNDRV_PCM_STATE_SUSPENDED:
2157 		err = -ESTRPIPE;
2158 		goto _end_unlock;
2159 	default:
2160 		err = -EBADFD;
2161 		goto _end_unlock;
2162 	}
2163 
2164 	while (size > 0) {
2165 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2166 		snd_pcm_uframes_t avail;
2167 		snd_pcm_uframes_t cont;
2168 		if (runtime->sleep_min == 0 && runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2169 			snd_pcm_update_hw_ptr(substream);
2170 		avail = snd_pcm_playback_avail(runtime);
2171 		if (((avail < runtime->control->avail_min && size > avail) ||
2172 		   (size >= runtime->xfer_align && avail < runtime->xfer_align))) {
2173 			wait_queue_t wait;
2174 			enum { READY, SIGNALED, ERROR, SUSPENDED, EXPIRED, DROPPED } state;
2175 			long tout;
2176 
2177 			if (nonblock) {
2178 				err = -EAGAIN;
2179 				goto _end_unlock;
2180 			}
2181 
2182 			init_waitqueue_entry(&wait, current);
2183 			add_wait_queue(&runtime->sleep, &wait);
2184 			while (1) {
2185 				if (signal_pending(current)) {
2186 					state = SIGNALED;
2187 					break;
2188 				}
2189 				set_current_state(TASK_INTERRUPTIBLE);
2190 				snd_pcm_stream_unlock_irq(substream);
2191 				tout = schedule_timeout(10 * HZ);
2192 				snd_pcm_stream_lock_irq(substream);
2193 				if (tout == 0) {
2194 					if (runtime->status->state != SNDRV_PCM_STATE_PREPARED &&
2195 					    runtime->status->state != SNDRV_PCM_STATE_PAUSED) {
2196 						state = runtime->status->state == SNDRV_PCM_STATE_SUSPENDED ? SUSPENDED : EXPIRED;
2197 						break;
2198 					}
2199 				}
2200 				switch (runtime->status->state) {
2201 				case SNDRV_PCM_STATE_XRUN:
2202 				case SNDRV_PCM_STATE_DRAINING:
2203 					state = ERROR;
2204 					goto _end_loop;
2205 				case SNDRV_PCM_STATE_SUSPENDED:
2206 					state = SUSPENDED;
2207 					goto _end_loop;
2208 				case SNDRV_PCM_STATE_SETUP:
2209 					state = DROPPED;
2210 					goto _end_loop;
2211 				default:
2212 					break;
2213 				}
2214 				avail = snd_pcm_playback_avail(runtime);
2215 				if (avail >= runtime->control->avail_min) {
2216 					state = READY;
2217 					break;
2218 				}
2219 			}
2220 		       _end_loop:
2221 			remove_wait_queue(&runtime->sleep, &wait);
2222 
2223 			switch (state) {
2224 			case ERROR:
2225 				err = -EPIPE;
2226 				goto _end_unlock;
2227 			case SUSPENDED:
2228 				err = -ESTRPIPE;
2229 				goto _end_unlock;
2230 			case SIGNALED:
2231 				err = -ERESTARTSYS;
2232 				goto _end_unlock;
2233 			case EXPIRED:
2234 				snd_printd("playback write error (DMA or IRQ trouble?)\n");
2235 				err = -EIO;
2236 				goto _end_unlock;
2237 			case DROPPED:
2238 				err = -EBADFD;
2239 				goto _end_unlock;
2240 			default:
2241 				break;
2242 			}
2243 		}
2244 		if (avail > runtime->xfer_align)
2245 			avail -= avail % runtime->xfer_align;
2246 		frames = size > avail ? avail : size;
2247 		cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2248 		if (frames > cont)
2249 			frames = cont;
2250 		snd_assert(frames != 0, snd_pcm_stream_unlock_irq(substream); return -EINVAL);
2251 		appl_ptr = runtime->control->appl_ptr;
2252 		appl_ofs = appl_ptr % runtime->buffer_size;
2253 		snd_pcm_stream_unlock_irq(substream);
2254 		if ((err = transfer(substream, appl_ofs, data, offset, frames)) < 0)
2255 			goto _end;
2256 		snd_pcm_stream_lock_irq(substream);
2257 		switch (runtime->status->state) {
2258 		case SNDRV_PCM_STATE_XRUN:
2259 			err = -EPIPE;
2260 			goto _end_unlock;
2261 		case SNDRV_PCM_STATE_SUSPENDED:
2262 			err = -ESTRPIPE;
2263 			goto _end_unlock;
2264 		default:
2265 			break;
2266 		}
2267 		appl_ptr += frames;
2268 		if (appl_ptr >= runtime->boundary)
2269 			appl_ptr -= runtime->boundary;
2270 		runtime->control->appl_ptr = appl_ptr;
2271 		if (substream->ops->ack)
2272 			substream->ops->ack(substream);
2273 
2274 		offset += frames;
2275 		size -= frames;
2276 		xfer += frames;
2277 		if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2278 		    snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2279 			err = snd_pcm_start(substream);
2280 			if (err < 0)
2281 				goto _end_unlock;
2282 		}
2283 		if (runtime->sleep_min &&
2284 		    runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2285 			snd_pcm_tick_prepare(substream);
2286 	}
2287  _end_unlock:
2288 	snd_pcm_stream_unlock_irq(substream);
2289  _end:
2290 	return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2291 }
2292 
2293 snd_pcm_sframes_t snd_pcm_lib_write(snd_pcm_substream_t *substream, const void __user *buf, snd_pcm_uframes_t size)
2294 {
2295 	snd_pcm_runtime_t *runtime;
2296 	int nonblock;
2297 
2298 	snd_assert(substream != NULL, return -ENXIO);
2299 	runtime = substream->runtime;
2300 	snd_assert(runtime != NULL, return -ENXIO);
2301 	snd_assert(substream->ops->copy != NULL || runtime->dma_area != NULL, return -EINVAL);
2302 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2303 		return -EBADFD;
2304 
2305 	snd_assert(substream->ffile != NULL, return -ENXIO);
2306 	nonblock = !!(substream->ffile->f_flags & O_NONBLOCK);
2307 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
2308 	if (substream->oss.oss) {
2309 		snd_pcm_oss_setup_t *setup = substream->oss.setup;
2310 		if (setup != NULL) {
2311 			if (setup->nonblock)
2312 				nonblock = 1;
2313 			else if (setup->block)
2314 				nonblock = 0;
2315 		}
2316 	}
2317 #endif
2318 
2319 	if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2320 	    runtime->channels > 1)
2321 		return -EINVAL;
2322 	return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
2323 				  snd_pcm_lib_write_transfer);
2324 }
2325 
2326 static int snd_pcm_lib_writev_transfer(snd_pcm_substream_t *substream,
2327 				       unsigned int hwoff,
2328 				       unsigned long data, unsigned int off,
2329 				       snd_pcm_uframes_t frames)
2330 {
2331 	snd_pcm_runtime_t *runtime = substream->runtime;
2332 	int err;
2333 	void __user **bufs = (void __user **)data;
2334 	int channels = runtime->channels;
2335 	int c;
2336 	if (substream->ops->copy) {
2337 		snd_assert(substream->ops->silence != NULL, return -EINVAL);
2338 		for (c = 0; c < channels; ++c, ++bufs) {
2339 			if (*bufs == NULL) {
2340 				if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
2341 					return err;
2342 			} else {
2343 				char __user *buf = *bufs + samples_to_bytes(runtime, off);
2344 				if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2345 					return err;
2346 			}
2347 		}
2348 	} else {
2349 		/* default transfer behaviour */
2350 		size_t dma_csize = runtime->dma_bytes / channels;
2351 		snd_assert(runtime->dma_area, return -EFAULT);
2352 		for (c = 0; c < channels; ++c, ++bufs) {
2353 			char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2354 			if (*bufs == NULL) {
2355 				snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
2356 			} else {
2357 				char __user *buf = *bufs + samples_to_bytes(runtime, off);
2358 				if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
2359 					return -EFAULT;
2360 			}
2361 		}
2362 	}
2363 	return 0;
2364 }
2365 
2366 snd_pcm_sframes_t snd_pcm_lib_writev(snd_pcm_substream_t *substream,
2367 				     void __user **bufs,
2368 				     snd_pcm_uframes_t frames)
2369 {
2370 	snd_pcm_runtime_t *runtime;
2371 	int nonblock;
2372 
2373 	snd_assert(substream != NULL, return -ENXIO);
2374 	runtime = substream->runtime;
2375 	snd_assert(runtime != NULL, return -ENXIO);
2376 	snd_assert(substream->ops->copy != NULL || runtime->dma_area != NULL, return -EINVAL);
2377 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2378 		return -EBADFD;
2379 
2380 	snd_assert(substream->ffile != NULL, return -ENXIO);
2381 	nonblock = !!(substream->ffile->f_flags & O_NONBLOCK);
2382 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
2383 	if (substream->oss.oss) {
2384 		snd_pcm_oss_setup_t *setup = substream->oss.setup;
2385 		if (setup != NULL) {
2386 			if (setup->nonblock)
2387 				nonblock = 1;
2388 			else if (setup->block)
2389 				nonblock = 0;
2390 		}
2391 	}
2392 #endif
2393 
2394 	if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2395 		return -EINVAL;
2396 	return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2397 				  nonblock, snd_pcm_lib_writev_transfer);
2398 }
2399 
2400 static int snd_pcm_lib_read_transfer(snd_pcm_substream_t *substream,
2401 				     unsigned int hwoff,
2402 				     unsigned long data, unsigned int off,
2403 				     snd_pcm_uframes_t frames)
2404 {
2405 	snd_pcm_runtime_t *runtime = substream->runtime;
2406 	int err;
2407 	char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2408 	if (substream->ops->copy) {
2409 		if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2410 			return err;
2411 	} else {
2412 		char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2413 		snd_assert(runtime->dma_area, return -EFAULT);
2414 		if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2415 			return -EFAULT;
2416 	}
2417 	return 0;
2418 }
2419 
2420 static snd_pcm_sframes_t snd_pcm_lib_read1(snd_pcm_substream_t *substream,
2421 					   unsigned long data,
2422 					   snd_pcm_uframes_t size,
2423 					   int nonblock,
2424 					   transfer_f transfer)
2425 {
2426 	snd_pcm_runtime_t *runtime = substream->runtime;
2427 	snd_pcm_uframes_t xfer = 0;
2428 	snd_pcm_uframes_t offset = 0;
2429 	int err = 0;
2430 
2431 	if (size == 0)
2432 		return 0;
2433 	if (size > runtime->xfer_align)
2434 		size -= size % runtime->xfer_align;
2435 
2436 	snd_pcm_stream_lock_irq(substream);
2437 	switch (runtime->status->state) {
2438 	case SNDRV_PCM_STATE_PREPARED:
2439 		if (size >= runtime->start_threshold) {
2440 			err = snd_pcm_start(substream);
2441 			if (err < 0)
2442 				goto _end_unlock;
2443 		}
2444 		break;
2445 	case SNDRV_PCM_STATE_DRAINING:
2446 	case SNDRV_PCM_STATE_RUNNING:
2447 	case SNDRV_PCM_STATE_PAUSED:
2448 		break;
2449 	case SNDRV_PCM_STATE_XRUN:
2450 		err = -EPIPE;
2451 		goto _end_unlock;
2452 	case SNDRV_PCM_STATE_SUSPENDED:
2453 		err = -ESTRPIPE;
2454 		goto _end_unlock;
2455 	default:
2456 		err = -EBADFD;
2457 		goto _end_unlock;
2458 	}
2459 
2460 	while (size > 0) {
2461 		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2462 		snd_pcm_uframes_t avail;
2463 		snd_pcm_uframes_t cont;
2464 		if (runtime->sleep_min == 0 && runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2465 			snd_pcm_update_hw_ptr(substream);
2466 	      __draining:
2467 		avail = snd_pcm_capture_avail(runtime);
2468 		if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
2469 			if (avail < runtime->xfer_align) {
2470 				err = -EPIPE;
2471 				goto _end_unlock;
2472 			}
2473 		} else if ((avail < runtime->control->avail_min && size > avail) ||
2474 			   (size >= runtime->xfer_align && avail < runtime->xfer_align)) {
2475 			wait_queue_t wait;
2476 			enum { READY, SIGNALED, ERROR, SUSPENDED, EXPIRED, DROPPED } state;
2477 			long tout;
2478 
2479 			if (nonblock) {
2480 				err = -EAGAIN;
2481 				goto _end_unlock;
2482 			}
2483 
2484 			init_waitqueue_entry(&wait, current);
2485 			add_wait_queue(&runtime->sleep, &wait);
2486 			while (1) {
2487 				if (signal_pending(current)) {
2488 					state = SIGNALED;
2489 					break;
2490 				}
2491 				set_current_state(TASK_INTERRUPTIBLE);
2492 				snd_pcm_stream_unlock_irq(substream);
2493 				tout = schedule_timeout(10 * HZ);
2494 				snd_pcm_stream_lock_irq(substream);
2495 				if (tout == 0) {
2496 					if (runtime->status->state != SNDRV_PCM_STATE_PREPARED &&
2497 					    runtime->status->state != SNDRV_PCM_STATE_PAUSED) {
2498 						state = runtime->status->state == SNDRV_PCM_STATE_SUSPENDED ? SUSPENDED : EXPIRED;
2499 						break;
2500 					}
2501 				}
2502 				switch (runtime->status->state) {
2503 				case SNDRV_PCM_STATE_XRUN:
2504 					state = ERROR;
2505 					goto _end_loop;
2506 				case SNDRV_PCM_STATE_SUSPENDED:
2507 					state = SUSPENDED;
2508 					goto _end_loop;
2509 				case SNDRV_PCM_STATE_DRAINING:
2510 					goto __draining;
2511 				case SNDRV_PCM_STATE_SETUP:
2512 					state = DROPPED;
2513 					goto _end_loop;
2514 				default:
2515 					break;
2516 				}
2517 				avail = snd_pcm_capture_avail(runtime);
2518 				if (avail >= runtime->control->avail_min) {
2519 					state = READY;
2520 					break;
2521 				}
2522 			}
2523 		       _end_loop:
2524 			remove_wait_queue(&runtime->sleep, &wait);
2525 
2526 			switch (state) {
2527 			case ERROR:
2528 				err = -EPIPE;
2529 				goto _end_unlock;
2530 			case SUSPENDED:
2531 				err = -ESTRPIPE;
2532 				goto _end_unlock;
2533 			case SIGNALED:
2534 				err = -ERESTARTSYS;
2535 				goto _end_unlock;
2536 			case EXPIRED:
2537 				snd_printd("capture read error (DMA or IRQ trouble?)\n");
2538 				err = -EIO;
2539 				goto _end_unlock;
2540 			case DROPPED:
2541 				err = -EBADFD;
2542 				goto _end_unlock;
2543 			default:
2544 				break;
2545 			}
2546 		}
2547 		if (avail > runtime->xfer_align)
2548 			avail -= avail % runtime->xfer_align;
2549 		frames = size > avail ? avail : size;
2550 		cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2551 		if (frames > cont)
2552 			frames = cont;
2553 		snd_assert(frames != 0, snd_pcm_stream_unlock_irq(substream); return -EINVAL);
2554 		appl_ptr = runtime->control->appl_ptr;
2555 		appl_ofs = appl_ptr % runtime->buffer_size;
2556 		snd_pcm_stream_unlock_irq(substream);
2557 		if ((err = transfer(substream, appl_ofs, data, offset, frames)) < 0)
2558 			goto _end;
2559 		snd_pcm_stream_lock_irq(substream);
2560 		switch (runtime->status->state) {
2561 		case SNDRV_PCM_STATE_XRUN:
2562 			err = -EPIPE;
2563 			goto _end_unlock;
2564 		case SNDRV_PCM_STATE_SUSPENDED:
2565 			err = -ESTRPIPE;
2566 			goto _end_unlock;
2567 		default:
2568 			break;
2569 		}
2570 		appl_ptr += frames;
2571 		if (appl_ptr >= runtime->boundary)
2572 			appl_ptr -= runtime->boundary;
2573 		runtime->control->appl_ptr = appl_ptr;
2574 		if (substream->ops->ack)
2575 			substream->ops->ack(substream);
2576 
2577 		offset += frames;
2578 		size -= frames;
2579 		xfer += frames;
2580 		if (runtime->sleep_min &&
2581 		    runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2582 			snd_pcm_tick_prepare(substream);
2583 	}
2584  _end_unlock:
2585 	snd_pcm_stream_unlock_irq(substream);
2586  _end:
2587 	return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2588 }
2589 
2590 snd_pcm_sframes_t snd_pcm_lib_read(snd_pcm_substream_t *substream, void __user *buf, snd_pcm_uframes_t size)
2591 {
2592 	snd_pcm_runtime_t *runtime;
2593 	int nonblock;
2594 
2595 	snd_assert(substream != NULL, return -ENXIO);
2596 	runtime = substream->runtime;
2597 	snd_assert(runtime != NULL, return -ENXIO);
2598 	snd_assert(substream->ops->copy != NULL || runtime->dma_area != NULL, return -EINVAL);
2599 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2600 		return -EBADFD;
2601 
2602 	snd_assert(substream->ffile != NULL, return -ENXIO);
2603 	nonblock = !!(substream->ffile->f_flags & O_NONBLOCK);
2604 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
2605 	if (substream->oss.oss) {
2606 		snd_pcm_oss_setup_t *setup = substream->oss.setup;
2607 		if (setup != NULL) {
2608 			if (setup->nonblock)
2609 				nonblock = 1;
2610 			else if (setup->block)
2611 				nonblock = 0;
2612 		}
2613 	}
2614 #endif
2615 	if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2616 		return -EINVAL;
2617 	return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2618 }
2619 
2620 static int snd_pcm_lib_readv_transfer(snd_pcm_substream_t *substream,
2621 				      unsigned int hwoff,
2622 				      unsigned long data, unsigned int off,
2623 				      snd_pcm_uframes_t frames)
2624 {
2625 	snd_pcm_runtime_t *runtime = substream->runtime;
2626 	int err;
2627 	void __user **bufs = (void __user **)data;
2628 	int channels = runtime->channels;
2629 	int c;
2630 	if (substream->ops->copy) {
2631 		for (c = 0; c < channels; ++c, ++bufs) {
2632 			char __user *buf;
2633 			if (*bufs == NULL)
2634 				continue;
2635 			buf = *bufs + samples_to_bytes(runtime, off);
2636 			if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2637 				return err;
2638 		}
2639 	} else {
2640 		snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2641 		snd_assert(runtime->dma_area, return -EFAULT);
2642 		for (c = 0; c < channels; ++c, ++bufs) {
2643 			char *hwbuf;
2644 			char __user *buf;
2645 			if (*bufs == NULL)
2646 				continue;
2647 
2648 			hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2649 			buf = *bufs + samples_to_bytes(runtime, off);
2650 			if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2651 				return -EFAULT;
2652 		}
2653 	}
2654 	return 0;
2655 }
2656 
2657 snd_pcm_sframes_t snd_pcm_lib_readv(snd_pcm_substream_t *substream,
2658 				    void __user **bufs,
2659 				    snd_pcm_uframes_t frames)
2660 {
2661 	snd_pcm_runtime_t *runtime;
2662 	int nonblock;
2663 
2664 	snd_assert(substream != NULL, return -ENXIO);
2665 	runtime = substream->runtime;
2666 	snd_assert(runtime != NULL, return -ENXIO);
2667 	snd_assert(substream->ops->copy != NULL || runtime->dma_area != NULL, return -EINVAL);
2668 	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2669 		return -EBADFD;
2670 
2671 	snd_assert(substream->ffile != NULL, return -ENXIO);
2672 	nonblock = !!(substream->ffile->f_flags & O_NONBLOCK);
2673 #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
2674 	if (substream->oss.oss) {
2675 		snd_pcm_oss_setup_t *setup = substream->oss.setup;
2676 		if (setup != NULL) {
2677 			if (setup->nonblock)
2678 				nonblock = 1;
2679 			else if (setup->block)
2680 				nonblock = 0;
2681 		}
2682 	}
2683 #endif
2684 
2685 	if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2686 		return -EINVAL;
2687 	return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2688 }
2689 
2690 /*
2691  *  Exported symbols
2692  */
2693 
2694 EXPORT_SYMBOL(snd_interval_refine);
2695 EXPORT_SYMBOL(snd_interval_list);
2696 EXPORT_SYMBOL(snd_interval_ratnum);
2697 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
2698 EXPORT_SYMBOL(_snd_pcm_hw_param_min);
2699 EXPORT_SYMBOL(_snd_pcm_hw_param_set);
2700 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
2701 EXPORT_SYMBOL(_snd_pcm_hw_param_setinteger);
2702 EXPORT_SYMBOL(snd_pcm_hw_param_value_min);
2703 EXPORT_SYMBOL(snd_pcm_hw_param_value_max);
2704 EXPORT_SYMBOL(snd_pcm_hw_param_mask);
2705 EXPORT_SYMBOL(snd_pcm_hw_param_first);
2706 EXPORT_SYMBOL(snd_pcm_hw_param_last);
2707 EXPORT_SYMBOL(snd_pcm_hw_param_near);
2708 EXPORT_SYMBOL(snd_pcm_hw_param_set);
2709 EXPORT_SYMBOL(snd_pcm_hw_refine);
2710 EXPORT_SYMBOL(snd_pcm_hw_constraints_init);
2711 EXPORT_SYMBOL(snd_pcm_hw_constraints_complete);
2712 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
2713 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
2714 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
2715 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
2716 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
2717 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
2718 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
2719 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
2720 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
2721 EXPORT_SYMBOL(snd_pcm_set_ops);
2722 EXPORT_SYMBOL(snd_pcm_set_sync);
2723 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
2724 EXPORT_SYMBOL(snd_pcm_stop);
2725 EXPORT_SYMBOL(snd_pcm_period_elapsed);
2726 EXPORT_SYMBOL(snd_pcm_lib_write);
2727 EXPORT_SYMBOL(snd_pcm_lib_read);
2728 EXPORT_SYMBOL(snd_pcm_lib_writev);
2729 EXPORT_SYMBOL(snd_pcm_lib_readv);
2730 EXPORT_SYMBOL(snd_pcm_lib_buffer_bytes);
2731 EXPORT_SYMBOL(snd_pcm_lib_period_bytes);
2732 /* pcm_memory.c */
2733 EXPORT_SYMBOL(snd_pcm_lib_preallocate_free_for_all);
2734 EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages);
2735 EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages_for_all);
2736 EXPORT_SYMBOL(snd_pcm_sgbuf_ops_page);
2737 EXPORT_SYMBOL(snd_pcm_lib_malloc_pages);
2738 EXPORT_SYMBOL(snd_pcm_lib_free_pages);
2739