1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  Digital Audio (PCM) abstract layer
   4 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   5 *                   Abramo Bagnara <abramo@alsa-project.org>
   6 */
   7
   8#include <linux/slab.h>
   9#include <linux/sched/signal.h>
  10#include <linux/time.h>
  11#include <linux/math64.h>
  12#include <linux/export.h>
  13#include <sound/core.h>
  14#include <sound/control.h>
  15#include <sound/tlv.h>
  16#include <sound/info.h>
  17#include <sound/pcm.h>
  18#include <sound/pcm_params.h>
  19#include <sound/timer.h>
  20
  21#include "pcm_local.h"
  22
  23#ifdef CONFIG_SND_PCM_XRUN_DEBUG
  24#define CREATE_TRACE_POINTS
  25#include "pcm_trace.h"
  26#else
  27#define trace_hwptr(substream, pos, in_interrupt)
  28#define trace_xrun(substream)
  29#define trace_hw_ptr_error(substream, reason)
  30#define trace_applptr(substream, prev, curr)
  31#endif
  32
  33static int fill_silence_frames(struct snd_pcm_substream *substream,
  34			       snd_pcm_uframes_t off, snd_pcm_uframes_t frames);
  35
  36/*
  37 * fill ring buffer with silence
  38 * runtime->silence_start: starting pointer to silence area
  39 * runtime->silence_filled: size filled with silence
  40 * runtime->silence_threshold: threshold from application
  41 * runtime->silence_size: maximal size from application
  42 *
  43 * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
  44 */
  45void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
  46{
  47	struct snd_pcm_runtime *runtime = substream->runtime;
  48	snd_pcm_uframes_t frames, ofs, transfer;
  49	int err;
  50
  51	if (runtime->silence_size < runtime->boundary) {
  52		snd_pcm_sframes_t noise_dist, n;
  53		snd_pcm_uframes_t appl_ptr = READ_ONCE(runtime->control->appl_ptr);
  54		if (runtime->silence_start != appl_ptr) {
  55			n = appl_ptr - runtime->silence_start;
  56			if (n < 0)
  57				n += runtime->boundary;
  58			if ((snd_pcm_uframes_t)n < runtime->silence_filled)
  59				runtime->silence_filled -= n;
  60			else
  61				runtime->silence_filled = 0;
  62			runtime->silence_start = appl_ptr;
  63		}
  64		if (runtime->silence_filled >= runtime->buffer_size)
  65			return;
  66		noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
  67		if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
  68			return;
  69		frames = runtime->silence_threshold - noise_dist;
  70		if (frames > runtime->silence_size)
  71			frames = runtime->silence_size;
  72	} else {
  73		if (new_hw_ptr == ULONG_MAX) {	/* initialization */
  74			snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
  75			if (avail > runtime->buffer_size)
  76				avail = runtime->buffer_size;
  77			runtime->silence_filled = avail > 0 ? avail : 0;
  78			runtime->silence_start = (runtime->status->hw_ptr +
  79						  runtime->silence_filled) %
  80						 runtime->boundary;
  81		} else {
  82			ofs = runtime->status->hw_ptr;
  83			frames = new_hw_ptr - ofs;
  84			if ((snd_pcm_sframes_t)frames < 0)
  85				frames += runtime->boundary;
  86			runtime->silence_filled -= frames;
  87			if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
  88				runtime->silence_filled = 0;
  89				runtime->silence_start = new_hw_ptr;
  90			} else {
  91				runtime->silence_start = ofs;
  92			}
  93		}
  94		frames = runtime->buffer_size - runtime->silence_filled;
  95	}
  96	if (snd_BUG_ON(frames > runtime->buffer_size))
  97		return;
  98	if (frames == 0)
  99		return;
 100	ofs = runtime->silence_start % runtime->buffer_size;
 101	while (frames > 0) {
 102		transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
 103		err = fill_silence_frames(substream, ofs, transfer);
 104		snd_BUG_ON(err < 0);
 105		runtime->silence_filled += transfer;
 106		frames -= transfer;
 107		ofs = 0;
 108	}
 
 109}
 110
 111#ifdef CONFIG_SND_DEBUG
 112void snd_pcm_debug_name(struct snd_pcm_substream *substream,
 113			   char *name, size_t len)
 114{
 115	snprintf(name, len, "pcmC%dD%d%c:%d",
 116		 substream->pcm->card->number,
 117		 substream->pcm->device,
 118		 substream->stream ? 'c' : 'p',
 119		 substream->number);
 120}
 121EXPORT_SYMBOL(snd_pcm_debug_name);
 122#endif
 123
 124#define XRUN_DEBUG_BASIC	(1<<0)
 125#define XRUN_DEBUG_STACK	(1<<1)	/* dump also stack */
 126#define XRUN_DEBUG_JIFFIESCHECK	(1<<2)	/* do jiffies check */
 127
 128#ifdef CONFIG_SND_PCM_XRUN_DEBUG
 129
 130#define xrun_debug(substream, mask) \
 131			((substream)->pstr->xrun_debug & (mask))
 132#else
 133#define xrun_debug(substream, mask)	0
 134#endif
 135
 136#define dump_stack_on_xrun(substream) do {			\
 137		if (xrun_debug(substream, XRUN_DEBUG_STACK))	\
 138			dump_stack();				\
 139	} while (0)
 140
 141/* call with stream lock held */
 142void __snd_pcm_xrun(struct snd_pcm_substream *substream)
 143{
 144	struct snd_pcm_runtime *runtime = substream->runtime;
 145
 146	trace_xrun(substream);
 147	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
 148		struct timespec64 tstamp;
 149
 150		snd_pcm_gettime(runtime, &tstamp);
 151		runtime->status->tstamp.tv_sec = tstamp.tv_sec;
 152		runtime->status->tstamp.tv_nsec = tstamp.tv_nsec;
 153	}
 154	snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 155	if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
 156		char name[16];
 157		snd_pcm_debug_name(substream, name, sizeof(name));
 158		pcm_warn(substream->pcm, "XRUN: %s\n", name);
 159		dump_stack_on_xrun(substream);
 160	}
 161}
 162
 163#ifdef CONFIG_SND_PCM_XRUN_DEBUG
 164#define hw_ptr_error(substream, in_interrupt, reason, fmt, args...)	\
 165	do {								\
 166		trace_hw_ptr_error(substream, reason);	\
 167		if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {		\
 168			pr_err_ratelimited("ALSA: PCM: [%c] " reason ": " fmt, \
 169					   (in_interrupt) ? 'Q' : 'P', ##args);	\
 170			dump_stack_on_xrun(substream);			\
 171		}							\
 172	} while (0)
 173
 174#else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
 175
 176#define hw_ptr_error(substream, fmt, args...) do { } while (0)
 177
 178#endif
 179
 180int snd_pcm_update_state(struct snd_pcm_substream *substream,
 181			 struct snd_pcm_runtime *runtime)
 182{
 183	snd_pcm_uframes_t avail;
 184
 185	avail = snd_pcm_avail(substream);
 186	if (avail > runtime->avail_max)
 187		runtime->avail_max = avail;
 188	if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
 189		if (avail >= runtime->buffer_size) {
 190			snd_pcm_drain_done(substream);
 191			return -EPIPE;
 192		}
 193	} else {
 194		if (avail >= runtime->stop_threshold) {
 195			__snd_pcm_xrun(substream);
 196			return -EPIPE;
 197		}
 198	}
 199	if (runtime->twake) {
 200		if (avail >= runtime->twake)
 201			wake_up(&runtime->tsleep);
 202	} else if (avail >= runtime->control->avail_min)
 203		wake_up(&runtime->sleep);
 204	return 0;
 205}
 206
 207static void update_audio_tstamp(struct snd_pcm_substream *substream,
 208				struct timespec64 *curr_tstamp,
 209				struct timespec64 *audio_tstamp)
 210{
 211	struct snd_pcm_runtime *runtime = substream->runtime;
 212	u64 audio_frames, audio_nsecs;
 213	struct timespec64 driver_tstamp;
 214
 215	if (runtime->tstamp_mode != SNDRV_PCM_TSTAMP_ENABLE)
 216		return;
 217
 218	if (!(substream->ops->get_time_info) ||
 219		(runtime->audio_tstamp_report.actual_type ==
 220			SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
 221
 222		/*
 223		 * provide audio timestamp derived from pointer position
 224		 * add delay only if requested
 225		 */
 226
 227		audio_frames = runtime->hw_ptr_wrap + runtime->status->hw_ptr;
 228
 229		if (runtime->audio_tstamp_config.report_delay) {
 230			if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 231				audio_frames -=  runtime->delay;
 232			else
 233				audio_frames +=  runtime->delay;
 234		}
 235		audio_nsecs = div_u64(audio_frames * 1000000000LL,
 236				runtime->rate);
 237		*audio_tstamp = ns_to_timespec64(audio_nsecs);
 238	}
 239
 240	if (runtime->status->audio_tstamp.tv_sec != audio_tstamp->tv_sec ||
 241	    runtime->status->audio_tstamp.tv_nsec != audio_tstamp->tv_nsec) {
 242		runtime->status->audio_tstamp.tv_sec = audio_tstamp->tv_sec;
 243		runtime->status->audio_tstamp.tv_nsec = audio_tstamp->tv_nsec;
 244		runtime->status->tstamp.tv_sec = curr_tstamp->tv_sec;
 245		runtime->status->tstamp.tv_nsec = curr_tstamp->tv_nsec;
 246	}
 247
 248
 249	/*
 250	 * re-take a driver timestamp to let apps detect if the reference tstamp
 251	 * read by low-level hardware was provided with a delay
 252	 */
 253	snd_pcm_gettime(substream->runtime, &driver_tstamp);
 254	runtime->driver_tstamp = driver_tstamp;
 255}
 256
 257static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
 258				  unsigned int in_interrupt)
 259{
 260	struct snd_pcm_runtime *runtime = substream->runtime;
 261	snd_pcm_uframes_t pos;
 262	snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
 263	snd_pcm_sframes_t hdelta, delta;
 264	unsigned long jdelta;
 265	unsigned long curr_jiffies;
 266	struct timespec64 curr_tstamp;
 267	struct timespec64 audio_tstamp;
 268	int crossed_boundary = 0;
 269
 270	old_hw_ptr = runtime->status->hw_ptr;
 271
 272	/*
 273	 * group pointer, time and jiffies reads to allow for more
 274	 * accurate correlations/corrections.
 275	 * The values are stored at the end of this routine after
 276	 * corrections for hw_ptr position
 277	 */
 278	pos = substream->ops->pointer(substream);
 279	curr_jiffies = jiffies;
 280	if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
 281		if ((substream->ops->get_time_info) &&
 282			(runtime->audio_tstamp_config.type_requested != SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
 283			substream->ops->get_time_info(substream, &curr_tstamp,
 284						&audio_tstamp,
 285						&runtime->audio_tstamp_config,
 286						&runtime->audio_tstamp_report);
 287
 288			/* re-test in case tstamp type is not supported in hardware and was demoted to DEFAULT */
 289			if (runtime->audio_tstamp_report.actual_type == SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)
 290				snd_pcm_gettime(runtime, &curr_tstamp);
 291		} else
 292			snd_pcm_gettime(runtime, &curr_tstamp);
 293	}
 294
 295	if (pos == SNDRV_PCM_POS_XRUN) {
 296		__snd_pcm_xrun(substream);
 297		return -EPIPE;
 298	}
 299	if (pos >= runtime->buffer_size) {
 300		if (printk_ratelimit()) {
 301			char name[16];
 302			snd_pcm_debug_name(substream, name, sizeof(name));
 303			pcm_err(substream->pcm,
 304				"invalid position: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
 305				name, pos, runtime->buffer_size,
 306				runtime->period_size);
 307		}
 308		pos = 0;
 309	}
 310	pos -= pos % runtime->min_align;
 311	trace_hwptr(substream, pos, in_interrupt);
 312	hw_base = runtime->hw_ptr_base;
 313	new_hw_ptr = hw_base + pos;
 314	if (in_interrupt) {
 315		/* we know that one period was processed */
 316		/* delta = "expected next hw_ptr" for in_interrupt != 0 */
 317		delta = runtime->hw_ptr_interrupt + runtime->period_size;
 318		if (delta > new_hw_ptr) {
 319			/* check for double acknowledged interrupts */
 320			hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 321			if (hdelta > runtime->hw_ptr_buffer_jiffies/2 + 1) {
 322				hw_base += runtime->buffer_size;
 323				if (hw_base >= runtime->boundary) {
 324					hw_base = 0;
 325					crossed_boundary++;
 326				}
 327				new_hw_ptr = hw_base + pos;
 328				goto __delta;
 329			}
 330		}
 331	}
 332	/* new_hw_ptr might be lower than old_hw_ptr in case when */
 333	/* pointer crosses the end of the ring buffer */
 334	if (new_hw_ptr < old_hw_ptr) {
 335		hw_base += runtime->buffer_size;
 336		if (hw_base >= runtime->boundary) {
 337			hw_base = 0;
 338			crossed_boundary++;
 339		}
 340		new_hw_ptr = hw_base + pos;
 341	}
 342      __delta:
 343	delta = new_hw_ptr - old_hw_ptr;
 344	if (delta < 0)
 345		delta += runtime->boundary;
 346
 347	if (runtime->no_period_wakeup) {
 348		snd_pcm_sframes_t xrun_threshold;
 349		/*
 350		 * Without regular period interrupts, we have to check
 351		 * the elapsed time to detect xruns.
 352		 */
 353		jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 354		if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
 355			goto no_delta_check;
 356		hdelta = jdelta - delta * HZ / runtime->rate;
 357		xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
 358		while (hdelta > xrun_threshold) {
 359			delta += runtime->buffer_size;
 360			hw_base += runtime->buffer_size;
 361			if (hw_base >= runtime->boundary) {
 362				hw_base = 0;
 363				crossed_boundary++;
 364			}
 365			new_hw_ptr = hw_base + pos;
 366			hdelta -= runtime->hw_ptr_buffer_jiffies;
 367		}
 368		goto no_delta_check;
 369	}
 370
 371	/* something must be really wrong */
 372	if (delta >= runtime->buffer_size + runtime->period_size) {
 373		hw_ptr_error(substream, in_interrupt, "Unexpected hw_ptr",
 374			     "(stream=%i, pos=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
 375			     substream->stream, (long)pos,
 376			     (long)new_hw_ptr, (long)old_hw_ptr);
 377		return 0;
 378	}
 379
 380	/* Do jiffies check only in xrun_debug mode */
 381	if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
 382		goto no_jiffies_check;
 383
 384	/* Skip the jiffies check for hardwares with BATCH flag.
 385	 * Such hardware usually just increases the position at each IRQ,
 386	 * thus it can't give any strange position.
 387	 */
 388	if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
 389		goto no_jiffies_check;
 390	hdelta = delta;
 391	if (hdelta < runtime->delay)
 392		goto no_jiffies_check;
 393	hdelta -= runtime->delay;
 394	jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 395	if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
 396		delta = jdelta /
 397			(((runtime->period_size * HZ) / runtime->rate)
 398								+ HZ/100);
 399		/* move new_hw_ptr according jiffies not pos variable */
 400		new_hw_ptr = old_hw_ptr;
 401		hw_base = delta;
 402		/* use loop to avoid checks for delta overflows */
 403		/* the delta value is small or zero in most cases */
 404		while (delta > 0) {
 405			new_hw_ptr += runtime->period_size;
 406			if (new_hw_ptr >= runtime->boundary) {
 407				new_hw_ptr -= runtime->boundary;
 408				crossed_boundary--;
 409			}
 410			delta--;
 411		}
 412		/* align hw_base to buffer_size */
 413		hw_ptr_error(substream, in_interrupt, "hw_ptr skipping",
 414			     "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
 415			     (long)pos, (long)hdelta,
 416			     (long)runtime->period_size, jdelta,
 417			     ((hdelta * HZ) / runtime->rate), hw_base,
 418			     (unsigned long)old_hw_ptr,
 419			     (unsigned long)new_hw_ptr);
 420		/* reset values to proper state */
 421		delta = 0;
 422		hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
 423	}
 424 no_jiffies_check:
 425	if (delta > runtime->period_size + runtime->period_size / 2) {
 426		hw_ptr_error(substream, in_interrupt,
 427			     "Lost interrupts?",
 428			     "(stream=%i, delta=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
 429			     substream->stream, (long)delta,
 430			     (long)new_hw_ptr,
 431			     (long)old_hw_ptr);
 432	}
 433
 434 no_delta_check:
 435	if (runtime->status->hw_ptr == new_hw_ptr) {
 436		runtime->hw_ptr_jiffies = curr_jiffies;
 437		update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
 438		return 0;
 439	}
 440
 441	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 442	    runtime->silence_size > 0)
 443		snd_pcm_playback_silence(substream, new_hw_ptr);
 444
 445	if (in_interrupt) {
 446		delta = new_hw_ptr - runtime->hw_ptr_interrupt;
 447		if (delta < 0)
 448			delta += runtime->boundary;
 449		delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
 450		runtime->hw_ptr_interrupt += delta;
 451		if (runtime->hw_ptr_interrupt >= runtime->boundary)
 452			runtime->hw_ptr_interrupt -= runtime->boundary;
 453	}
 454	runtime->hw_ptr_base = hw_base;
 455	runtime->status->hw_ptr = new_hw_ptr;
 456	runtime->hw_ptr_jiffies = curr_jiffies;
 457	if (crossed_boundary) {
 458		snd_BUG_ON(crossed_boundary != 1);
 459		runtime->hw_ptr_wrap += runtime->boundary;
 460	}
 461
 462	update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
 463
 464	return snd_pcm_update_state(substream, runtime);
 465}
 466
 467/* CAUTION: call it with irq disabled */
 468int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
 469{
 470	return snd_pcm_update_hw_ptr0(substream, 0);
 471}
 472
 473/**
 474 * snd_pcm_set_ops - set the PCM operators
 475 * @pcm: the pcm instance
 476 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
 477 * @ops: the operator table
 478 *
 479 * Sets the given PCM operators to the pcm instance.
 480 */
 481void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
 482		     const struct snd_pcm_ops *ops)
 483{
 484	struct snd_pcm_str *stream = &pcm->streams[direction];
 485	struct snd_pcm_substream *substream;
 486	
 487	for (substream = stream->substream; substream != NULL; substream = substream->next)
 488		substream->ops = ops;
 489}
 490EXPORT_SYMBOL(snd_pcm_set_ops);
 491
 492/**
 493 * snd_pcm_sync - set the PCM sync id
 494 * @substream: the pcm substream
 495 *
 496 * Sets the PCM sync identifier for the card.
 497 */
 498void snd_pcm_set_sync(struct snd_pcm_substream *substream)
 499{
 500	struct snd_pcm_runtime *runtime = substream->runtime;
 501	
 502	runtime->sync.id32[0] = substream->pcm->card->number;
 503	runtime->sync.id32[1] = -1;
 504	runtime->sync.id32[2] = -1;
 505	runtime->sync.id32[3] = -1;
 506}
 507EXPORT_SYMBOL(snd_pcm_set_sync);
 508
 509/*
 510 *  Standard ioctl routine
 511 */
 512
 513static inline unsigned int div32(unsigned int a, unsigned int b, 
 514				 unsigned int *r)
 515{
 516	if (b == 0) {
 517		*r = 0;
 518		return UINT_MAX;
 519	}
 520	*r = a % b;
 521	return a / b;
 522}
 523
 524static inline unsigned int div_down(unsigned int a, unsigned int b)
 525{
 526	if (b == 0)
 527		return UINT_MAX;
 528	return a / b;
 529}
 530
 531static inline unsigned int div_up(unsigned int a, unsigned int b)
 532{
 533	unsigned int r;
 534	unsigned int q;
 535	if (b == 0)
 536		return UINT_MAX;
 537	q = div32(a, b, &r);
 538	if (r)
 539		++q;
 540	return q;
 541}
 542
 543static inline unsigned int mul(unsigned int a, unsigned int b)
 544{
 545	if (a == 0)
 546		return 0;
 547	if (div_down(UINT_MAX, a) < b)
 548		return UINT_MAX;
 549	return a * b;
 550}
 551
 552static inline unsigned int muldiv32(unsigned int a, unsigned int b,
 553				    unsigned int c, unsigned int *r)
 554{
 555	u_int64_t n = (u_int64_t) a * b;
 556	if (c == 0) {
 557		*r = 0;
 558		return UINT_MAX;
 559	}
 560	n = div_u64_rem(n, c, r);
 561	if (n >= UINT_MAX) {
 562		*r = 0;
 563		return UINT_MAX;
 564	}
 565	return n;
 566}
 567
 568/**
 569 * snd_interval_refine - refine the interval value of configurator
 570 * @i: the interval value to refine
 571 * @v: the interval value to refer to
 572 *
 573 * Refines the interval value with the reference value.
 574 * The interval is changed to the range satisfying both intervals.
 575 * The interval status (min, max, integer, etc.) are evaluated.
 576 *
 577 * Return: Positive if the value is changed, zero if it's not changed, or a
 578 * negative error code.
 579 */
 580int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
 581{
 582	int changed = 0;
 583	if (snd_BUG_ON(snd_interval_empty(i)))
 584		return -EINVAL;
 585	if (i->min < v->min) {
 586		i->min = v->min;
 587		i->openmin = v->openmin;
 588		changed = 1;
 589	} else if (i->min == v->min && !i->openmin && v->openmin) {
 590		i->openmin = 1;
 591		changed = 1;
 592	}
 593	if (i->max > v->max) {
 594		i->max = v->max;
 595		i->openmax = v->openmax;
 596		changed = 1;
 597	} else if (i->max == v->max && !i->openmax && v->openmax) {
 598		i->openmax = 1;
 599		changed = 1;
 600	}
 601	if (!i->integer && v->integer) {
 602		i->integer = 1;
 603		changed = 1;
 604	}
 605	if (i->integer) {
 606		if (i->openmin) {
 607			i->min++;
 608			i->openmin = 0;
 609		}
 610		if (i->openmax) {
 611			i->max--;
 612			i->openmax = 0;
 613		}
 614	} else if (!i->openmin && !i->openmax && i->min == i->max)
 615		i->integer = 1;
 616	if (snd_interval_checkempty(i)) {
 617		snd_interval_none(i);
 618		return -EINVAL;
 619	}
 620	return changed;
 621}
 622EXPORT_SYMBOL(snd_interval_refine);
 623
 624static int snd_interval_refine_first(struct snd_interval *i)
 625{
 626	const unsigned int last_max = i->max;
 627
 628	if (snd_BUG_ON(snd_interval_empty(i)))
 629		return -EINVAL;
 630	if (snd_interval_single(i))
 631		return 0;
 632	i->max = i->min;
 633	if (i->openmin)
 634		i->max++;
 635	/* only exclude max value if also excluded before refine */
 636	i->openmax = (i->openmax && i->max >= last_max);
 637	return 1;
 638}
 639
 640static int snd_interval_refine_last(struct snd_interval *i)
 641{
 642	const unsigned int last_min = i->min;
 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	if (i->openmax)
 650		i->min--;
 651	/* only exclude min value if also excluded before refine */
 652	i->openmin = (i->openmin && i->min <= last_min);
 653	return 1;
 654}
 655
 656void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 657{
 658	if (a->empty || b->empty) {
 659		snd_interval_none(c);
 660		return;
 661	}
 662	c->empty = 0;
 663	c->min = mul(a->min, b->min);
 664	c->openmin = (a->openmin || b->openmin);
 665	c->max = mul(a->max,  b->max);
 666	c->openmax = (a->openmax || b->openmax);
 667	c->integer = (a->integer && b->integer);
 668}
 669
 670/**
 671 * snd_interval_div - refine the interval value with division
 672 * @a: dividend
 673 * @b: divisor
 674 * @c: quotient
 675 *
 676 * c = a / b
 677 *
 678 * Returns non-zero if the value is changed, zero if not changed.
 679 */
 680void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 681{
 682	unsigned int r;
 683	if (a->empty || b->empty) {
 684		snd_interval_none(c);
 685		return;
 686	}
 687	c->empty = 0;
 688	c->min = div32(a->min, b->max, &r);
 689	c->openmin = (r || a->openmin || b->openmax);
 690	if (b->min > 0) {
 691		c->max = div32(a->max, b->min, &r);
 692		if (r) {
 693			c->max++;
 694			c->openmax = 1;
 695		} else
 696			c->openmax = (a->openmax || b->openmin);
 697	} else {
 698		c->max = UINT_MAX;
 699		c->openmax = 0;
 700	}
 701	c->integer = 0;
 702}
 703
 704/**
 705 * snd_interval_muldivk - refine the interval value
 706 * @a: dividend 1
 707 * @b: dividend 2
 708 * @k: divisor (as integer)
 709 * @c: result
 710  *
 711 * c = a * b / k
 712 *
 713 * Returns non-zero if the value is changed, zero if not changed.
 714 */
 715void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
 716		      unsigned int k, struct snd_interval *c)
 717{
 718	unsigned int r;
 719	if (a->empty || b->empty) {
 720		snd_interval_none(c);
 721		return;
 722	}
 723	c->empty = 0;
 724	c->min = muldiv32(a->min, b->min, k, &r);
 725	c->openmin = (r || a->openmin || b->openmin);
 726	c->max = muldiv32(a->max, b->max, k, &r);
 727	if (r) {
 728		c->max++;
 729		c->openmax = 1;
 730	} else
 731		c->openmax = (a->openmax || b->openmax);
 732	c->integer = 0;
 733}
 734
 735/**
 736 * snd_interval_mulkdiv - refine the interval value
 737 * @a: dividend 1
 738 * @k: dividend 2 (as integer)
 739 * @b: divisor
 740 * @c: result
 741 *
 742 * c = a * k / b
 743 *
 744 * Returns non-zero if the value is changed, zero if not changed.
 745 */
 746void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
 747		      const struct snd_interval *b, struct snd_interval *c)
 748{
 749	unsigned int r;
 750	if (a->empty || b->empty) {
 751		snd_interval_none(c);
 752		return;
 753	}
 754	c->empty = 0;
 755	c->min = muldiv32(a->min, k, b->max, &r);
 756	c->openmin = (r || a->openmin || b->openmax);
 757	if (b->min > 0) {
 758		c->max = muldiv32(a->max, k, b->min, &r);
 759		if (r) {
 760			c->max++;
 761			c->openmax = 1;
 762		} else
 763			c->openmax = (a->openmax || b->openmin);
 764	} else {
 765		c->max = UINT_MAX;
 766		c->openmax = 0;
 767	}
 768	c->integer = 0;
 769}
 770
 771/* ---- */
 772
 773
 774/**
 775 * snd_interval_ratnum - refine the interval value
 776 * @i: interval to refine
 777 * @rats_count: number of ratnum_t 
 778 * @rats: ratnum_t array
 779 * @nump: pointer to store the resultant numerator
 780 * @denp: pointer to store the resultant denominator
 781 *
 782 * Return: Positive if the value is changed, zero if it's not changed, or a
 783 * negative error code.
 784 */
 785int snd_interval_ratnum(struct snd_interval *i,
 786			unsigned int rats_count, const struct snd_ratnum *rats,
 787			unsigned int *nump, unsigned int *denp)
 788{
 789	unsigned int best_num, best_den;
 790	int best_diff;
 791	unsigned int k;
 792	struct snd_interval t;
 793	int err;
 794	unsigned int result_num, result_den;
 795	int result_diff;
 796
 797	best_num = best_den = best_diff = 0;
 798	for (k = 0; k < rats_count; ++k) {
 799		unsigned int num = rats[k].num;
 800		unsigned int den;
 801		unsigned int q = i->min;
 802		int diff;
 803		if (q == 0)
 804			q = 1;
 805		den = div_up(num, q);
 806		if (den < rats[k].den_min)
 807			continue;
 808		if (den > rats[k].den_max)
 809			den = rats[k].den_max;
 810		else {
 811			unsigned int r;
 812			r = (den - rats[k].den_min) % rats[k].den_step;
 813			if (r != 0)
 814				den -= r;
 815		}
 816		diff = num - q * den;
 817		if (diff < 0)
 818			diff = -diff;
 819		if (best_num == 0 ||
 820		    diff * best_den < best_diff * den) {
 821			best_diff = diff;
 822			best_den = den;
 823			best_num = num;
 824		}
 825	}
 826	if (best_den == 0) {
 827		i->empty = 1;
 828		return -EINVAL;
 829	}
 830	t.min = div_down(best_num, best_den);
 831	t.openmin = !!(best_num % best_den);
 832	
 833	result_num = best_num;
 834	result_diff = best_diff;
 835	result_den = best_den;
 836	best_num = best_den = best_diff = 0;
 837	for (k = 0; k < rats_count; ++k) {
 838		unsigned int num = rats[k].num;
 839		unsigned int den;
 840		unsigned int q = i->max;
 841		int diff;
 842		if (q == 0) {
 843			i->empty = 1;
 844			return -EINVAL;
 845		}
 846		den = div_down(num, q);
 847		if (den > rats[k].den_max)
 848			continue;
 849		if (den < rats[k].den_min)
 850			den = rats[k].den_min;
 851		else {
 852			unsigned int r;
 853			r = (den - rats[k].den_min) % rats[k].den_step;
 854			if (r != 0)
 855				den += rats[k].den_step - r;
 856		}
 857		diff = q * den - num;
 858		if (diff < 0)
 859			diff = -diff;
 860		if (best_num == 0 ||
 861		    diff * best_den < best_diff * den) {
 862			best_diff = diff;
 863			best_den = den;
 864			best_num = num;
 865		}
 866	}
 867	if (best_den == 0) {
 868		i->empty = 1;
 869		return -EINVAL;
 870	}
 871	t.max = div_up(best_num, best_den);
 872	t.openmax = !!(best_num % best_den);
 873	t.integer = 0;
 874	err = snd_interval_refine(i, &t);
 875	if (err < 0)
 876		return err;
 877
 878	if (snd_interval_single(i)) {
 879		if (best_diff * result_den < result_diff * best_den) {
 880			result_num = best_num;
 881			result_den = best_den;
 882		}
 883		if (nump)
 884			*nump = result_num;
 885		if (denp)
 886			*denp = result_den;
 887	}
 888	return err;
 889}
 890EXPORT_SYMBOL(snd_interval_ratnum);
 891
 892/**
 893 * snd_interval_ratden - refine the interval value
 894 * @i: interval to refine
 895 * @rats_count: number of struct ratden
 896 * @rats: struct ratden array
 897 * @nump: pointer to store the resultant numerator
 898 * @denp: pointer to store the resultant denominator
 899 *
 900 * Return: Positive if the value is changed, zero if it's not changed, or a
 901 * negative error code.
 902 */
 903static int snd_interval_ratden(struct snd_interval *i,
 904			       unsigned int rats_count,
 905			       const struct snd_ratden *rats,
 906			       unsigned int *nump, unsigned int *denp)
 907{
 908	unsigned int best_num, best_diff, best_den;
 909	unsigned int k;
 910	struct snd_interval t;
 911	int err;
 912
 913	best_num = best_den = best_diff = 0;
 914	for (k = 0; k < rats_count; ++k) {
 915		unsigned int num;
 916		unsigned int den = rats[k].den;
 917		unsigned int q = i->min;
 918		int diff;
 919		num = mul(q, den);
 920		if (num > rats[k].num_max)
 921			continue;
 922		if (num < rats[k].num_min)
 923			num = rats[k].num_max;
 924		else {
 925			unsigned int r;
 926			r = (num - rats[k].num_min) % rats[k].num_step;
 927			if (r != 0)
 928				num += rats[k].num_step - r;
 929		}
 930		diff = num - q * den;
 931		if (best_num == 0 ||
 932		    diff * best_den < best_diff * den) {
 933			best_diff = diff;
 934			best_den = den;
 935			best_num = num;
 936		}
 937	}
 938	if (best_den == 0) {
 939		i->empty = 1;
 940		return -EINVAL;
 941	}
 942	t.min = div_down(best_num, best_den);
 943	t.openmin = !!(best_num % best_den);
 944	
 945	best_num = best_den = best_diff = 0;
 946	for (k = 0; k < rats_count; ++k) {
 947		unsigned int num;
 948		unsigned int den = rats[k].den;
 949		unsigned int q = i->max;
 950		int diff;
 951		num = mul(q, den);
 952		if (num < rats[k].num_min)
 953			continue;
 954		if (num > rats[k].num_max)
 955			num = rats[k].num_max;
 956		else {
 957			unsigned int r;
 958			r = (num - rats[k].num_min) % rats[k].num_step;
 959			if (r != 0)
 960				num -= r;
 961		}
 962		diff = q * den - num;
 963		if (best_num == 0 ||
 964		    diff * best_den < best_diff * den) {
 965			best_diff = diff;
 966			best_den = den;
 967			best_num = num;
 968		}
 969	}
 970	if (best_den == 0) {
 971		i->empty = 1;
 972		return -EINVAL;
 973	}
 974	t.max = div_up(best_num, best_den);
 975	t.openmax = !!(best_num % best_den);
 976	t.integer = 0;
 977	err = snd_interval_refine(i, &t);
 978	if (err < 0)
 979		return err;
 980
 981	if (snd_interval_single(i)) {
 982		if (nump)
 983			*nump = best_num;
 984		if (denp)
 985			*denp = best_den;
 986	}
 987	return err;
 988}
 989
 990/**
 991 * snd_interval_list - refine the interval value from the list
 992 * @i: the interval value to refine
 993 * @count: the number of elements in the list
 994 * @list: the value list
 995 * @mask: the bit-mask to evaluate
 996 *
 997 * Refines the interval value from the list.
 998 * When mask is non-zero, only the elements corresponding to bit 1 are
 999 * evaluated.
1000 *
1001 * Return: Positive if the value is changed, zero if it's not changed, or a
1002 * negative error code.
1003 */
1004int snd_interval_list(struct snd_interval *i, unsigned int count,
1005		      const unsigned int *list, unsigned int mask)
1006{
1007        unsigned int k;
1008	struct snd_interval list_range;
1009
1010	if (!count) {
1011		i->empty = 1;
1012		return -EINVAL;
1013	}
1014	snd_interval_any(&list_range);
1015	list_range.min = UINT_MAX;
1016	list_range.max = 0;
1017        for (k = 0; k < count; k++) {
1018		if (mask && !(mask & (1 << k)))
1019			continue;
1020		if (!snd_interval_test(i, list[k]))
1021			continue;
1022		list_range.min = min(list_range.min, list[k]);
1023		list_range.max = max(list_range.max, list[k]);
1024        }
1025	return snd_interval_refine(i, &list_range);
1026}
1027EXPORT_SYMBOL(snd_interval_list);
1028
1029/**
1030 * snd_interval_ranges - refine the interval value from the list of ranges
1031 * @i: the interval value to refine
1032 * @count: the number of elements in the list of ranges
1033 * @ranges: the ranges list
1034 * @mask: the bit-mask to evaluate
1035 *
1036 * Refines the interval value from the list of ranges.
1037 * When mask is non-zero, only the elements corresponding to bit 1 are
1038 * evaluated.
1039 *
1040 * Return: Positive if the value is changed, zero if it's not changed, or a
1041 * negative error code.
1042 */
1043int snd_interval_ranges(struct snd_interval *i, unsigned int count,
1044			const struct snd_interval *ranges, unsigned int mask)
1045{
1046	unsigned int k;
1047	struct snd_interval range_union;
1048	struct snd_interval range;
1049
1050	if (!count) {
1051		snd_interval_none(i);
1052		return -EINVAL;
1053	}
1054	snd_interval_any(&range_union);
1055	range_union.min = UINT_MAX;
1056	range_union.max = 0;
1057	for (k = 0; k < count; k++) {
1058		if (mask && !(mask & (1 << k)))
1059			continue;
1060		snd_interval_copy(&range, &ranges[k]);
1061		if (snd_interval_refine(&range, i) < 0)
1062			continue;
1063		if (snd_interval_empty(&range))
1064			continue;
1065
1066		if (range.min < range_union.min) {
1067			range_union.min = range.min;
1068			range_union.openmin = 1;
1069		}
1070		if (range.min == range_union.min && !range.openmin)
1071			range_union.openmin = 0;
1072		if (range.max > range_union.max) {
1073			range_union.max = range.max;
1074			range_union.openmax = 1;
1075		}
1076		if (range.max == range_union.max && !range.openmax)
1077			range_union.openmax = 0;
1078	}
1079	return snd_interval_refine(i, &range_union);
1080}
1081EXPORT_SYMBOL(snd_interval_ranges);
1082
1083static int snd_interval_step(struct snd_interval *i, unsigned int step)
1084{
1085	unsigned int n;
1086	int changed = 0;
1087	n = i->min % step;
1088	if (n != 0 || i->openmin) {
1089		i->min += step - n;
1090		i->openmin = 0;
1091		changed = 1;
1092	}
1093	n = i->max % step;
1094	if (n != 0 || i->openmax) {
1095		i->max -= n;
1096		i->openmax = 0;
1097		changed = 1;
1098	}
1099	if (snd_interval_checkempty(i)) {
1100		i->empty = 1;
1101		return -EINVAL;
1102	}
1103	return changed;
1104}
1105
1106/* Info constraints helpers */
1107
1108/**
1109 * snd_pcm_hw_rule_add - add the hw-constraint rule
1110 * @runtime: the pcm runtime instance
1111 * @cond: condition bits
1112 * @var: the variable to evaluate
1113 * @func: the evaluation function
1114 * @private: the private data pointer passed to function
1115 * @dep: the dependent variables
1116 *
1117 * Return: Zero if successful, or a negative error code on failure.
1118 */
1119int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1120			int var,
1121			snd_pcm_hw_rule_func_t func, void *private,
1122			int dep, ...)
1123{
1124	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1125	struct snd_pcm_hw_rule *c;
1126	unsigned int k;
1127	va_list args;
1128	va_start(args, dep);
1129	if (constrs->rules_num >= constrs->rules_all) {
1130		struct snd_pcm_hw_rule *new;
1131		unsigned int new_rules = constrs->rules_all + 16;
1132		new = krealloc(constrs->rules, new_rules * sizeof(*c),
1133			       GFP_KERNEL);
1134		if (!new) {
1135			va_end(args);
1136			return -ENOMEM;
1137		}
1138		constrs->rules = new;
1139		constrs->rules_all = new_rules;
1140	}
1141	c = &constrs->rules[constrs->rules_num];
1142	c->cond = cond;
1143	c->func = func;
1144	c->var = var;
1145	c->private = private;
1146	k = 0;
1147	while (1) {
1148		if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1149			va_end(args);
1150			return -EINVAL;
1151		}
1152		c->deps[k++] = dep;
1153		if (dep < 0)
1154			break;
1155		dep = va_arg(args, int);
1156	}
1157	constrs->rules_num++;
1158	va_end(args);
1159	return 0;
1160}
1161EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1162
1163/**
1164 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1165 * @runtime: PCM runtime instance
1166 * @var: hw_params variable to apply the mask
1167 * @mask: the bitmap mask
1168 *
1169 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1170 *
1171 * Return: Zero if successful, or a negative error code on failure.
1172 */
1173int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1174			       u_int32_t mask)
1175{
1176	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1177	struct snd_mask *maskp = constrs_mask(constrs, var);
1178	*maskp->bits &= mask;
1179	memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1180	if (*maskp->bits == 0)
1181		return -EINVAL;
1182	return 0;
1183}
1184
1185/**
1186 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1187 * @runtime: PCM runtime instance
1188 * @var: hw_params variable to apply the mask
1189 * @mask: the 64bit bitmap mask
1190 *
1191 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1192 *
1193 * Return: Zero if successful, or a negative error code on failure.
1194 */
1195int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1196				 u_int64_t mask)
1197{
1198	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1199	struct snd_mask *maskp = constrs_mask(constrs, var);
1200	maskp->bits[0] &= (u_int32_t)mask;
1201	maskp->bits[1] &= (u_int32_t)(mask >> 32);
1202	memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1203	if (! maskp->bits[0] && ! maskp->bits[1])
1204		return -EINVAL;
1205	return 0;
1206}
1207EXPORT_SYMBOL(snd_pcm_hw_constraint_mask64);
1208
1209/**
1210 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1211 * @runtime: PCM runtime instance
1212 * @var: hw_params variable to apply the integer constraint
1213 *
1214 * Apply the constraint of integer to an interval parameter.
1215 *
1216 * Return: Positive if the value is changed, zero if it's not changed, or a
1217 * negative error code.
1218 */
1219int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1220{
1221	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1222	return snd_interval_setinteger(constrs_interval(constrs, var));
1223}
1224EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1225
1226/**
1227 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1228 * @runtime: PCM runtime instance
1229 * @var: hw_params variable to apply the range
1230 * @min: the minimal value
1231 * @max: the maximal value
1232 * 
1233 * Apply the min/max range constraint to an interval parameter.
1234 *
1235 * Return: Positive if the value is changed, zero if it's not changed, or a
1236 * negative error code.
1237 */
1238int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1239				 unsigned int min, unsigned int max)
1240{
1241	struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1242	struct snd_interval t;
1243	t.min = min;
1244	t.max = max;
1245	t.openmin = t.openmax = 0;
1246	t.integer = 0;
1247	return snd_interval_refine(constrs_interval(constrs, var), &t);
1248}
1249EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1250
1251static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1252				struct snd_pcm_hw_rule *rule)
1253{
1254	struct snd_pcm_hw_constraint_list *list = rule->private;
1255	return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1256}		
1257
1258
1259/**
1260 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1261 * @runtime: PCM runtime instance
1262 * @cond: condition bits
1263 * @var: hw_params variable to apply the list constraint
1264 * @l: list
1265 * 
1266 * Apply the list of constraints to an interval parameter.
1267 *
1268 * Return: Zero if successful, or a negative error code on failure.
1269 */
1270int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1271			       unsigned int cond,
1272			       snd_pcm_hw_param_t var,
1273			       const struct snd_pcm_hw_constraint_list *l)
1274{
1275	return snd_pcm_hw_rule_add(runtime, cond, var,
1276				   snd_pcm_hw_rule_list, (void *)l,
1277				   var, -1);
1278}
1279EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1280
1281static int snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params *params,
1282				  struct snd_pcm_hw_rule *rule)
1283{
1284	struct snd_pcm_hw_constraint_ranges *r = rule->private;
1285	return snd_interval_ranges(hw_param_interval(params, rule->var),
1286				   r->count, r->ranges, r->mask);
1287}
1288
1289
1290/**
1291 * snd_pcm_hw_constraint_ranges - apply list of range constraints to a parameter
1292 * @runtime: PCM runtime instance
1293 * @cond: condition bits
1294 * @var: hw_params variable to apply the list of range constraints
1295 * @r: ranges
1296 *
1297 * Apply the list of range constraints to an interval parameter.
1298 *
1299 * Return: Zero if successful, or a negative error code on failure.
1300 */
1301int snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime *runtime,
1302				 unsigned int cond,
1303				 snd_pcm_hw_param_t var,
1304				 const struct snd_pcm_hw_constraint_ranges *r)
1305{
1306	return snd_pcm_hw_rule_add(runtime, cond, var,
1307				   snd_pcm_hw_rule_ranges, (void *)r,
1308				   var, -1);
1309}
1310EXPORT_SYMBOL(snd_pcm_hw_constraint_ranges);
1311
1312static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1313				   struct snd_pcm_hw_rule *rule)
1314{
1315	const struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1316	unsigned int num = 0, den = 0;
1317	int err;
1318	err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1319				  r->nrats, r->rats, &num, &den);
1320	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1321		params->rate_num = num;
1322		params->rate_den = den;
1323	}
1324	return err;
1325}
1326
1327/**
1328 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1329 * @runtime: PCM runtime instance
1330 * @cond: condition bits
1331 * @var: hw_params variable to apply the ratnums constraint
1332 * @r: struct snd_ratnums constriants
1333 *
1334 * Return: Zero if successful, or a negative error code on failure.
1335 */
1336int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime, 
1337				  unsigned int cond,
1338				  snd_pcm_hw_param_t var,
1339				  const struct snd_pcm_hw_constraint_ratnums *r)
1340{
1341	return snd_pcm_hw_rule_add(runtime, cond, var,
1342				   snd_pcm_hw_rule_ratnums, (void *)r,
1343				   var, -1);
1344}
1345EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1346
1347static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1348				   struct snd_pcm_hw_rule *rule)
1349{
1350	const struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1351	unsigned int num = 0, den = 0;
1352	int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1353				  r->nrats, r->rats, &num, &den);
1354	if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1355		params->rate_num = num;
1356		params->rate_den = den;
1357	}
1358	return err;
1359}
1360
1361/**
1362 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1363 * @runtime: PCM runtime instance
1364 * @cond: condition bits
1365 * @var: hw_params variable to apply the ratdens constraint
1366 * @r: struct snd_ratdens constriants
1367 *
1368 * Return: Zero if successful, or a negative error code on failure.
1369 */
1370int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime, 
1371				  unsigned int cond,
1372				  snd_pcm_hw_param_t var,
1373				  const struct snd_pcm_hw_constraint_ratdens *r)
1374{
1375	return snd_pcm_hw_rule_add(runtime, cond, var,
1376				   snd_pcm_hw_rule_ratdens, (void *)r,
1377				   var, -1);
1378}
1379EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1380
1381static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1382				  struct snd_pcm_hw_rule *rule)
1383{
1384	unsigned int l = (unsigned long) rule->private;
1385	int width = l & 0xffff;
1386	unsigned int msbits = l >> 16;
1387	const struct snd_interval *i =
1388		hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1389
1390	if (!snd_interval_single(i))
1391		return 0;
1392
1393	if ((snd_interval_value(i) == width) ||
1394	    (width == 0 && snd_interval_value(i) > msbits))
1395		params->msbits = min_not_zero(params->msbits, msbits);
1396
1397	return 0;
1398}
1399
1400/**
1401 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1402 * @runtime: PCM runtime instance
1403 * @cond: condition bits
1404 * @width: sample bits width
1405 * @msbits: msbits width
1406 *
1407 * This constraint will set the number of most significant bits (msbits) if a
1408 * sample format with the specified width has been select. If width is set to 0
1409 * the msbits will be set for any sample format with a width larger than the
1410 * specified msbits.
1411 *
1412 * Return: Zero if successful, or a negative error code on failure.
1413 */
1414int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime, 
1415				 unsigned int cond,
1416				 unsigned int width,
1417				 unsigned int msbits)
1418{
1419	unsigned long l = (msbits << 16) | width;
1420	return snd_pcm_hw_rule_add(runtime, cond, -1,
1421				    snd_pcm_hw_rule_msbits,
1422				    (void*) l,
1423				    SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1424}
1425EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1426
1427static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1428				struct snd_pcm_hw_rule *rule)
1429{
1430	unsigned long step = (unsigned long) rule->private;
1431	return snd_interval_step(hw_param_interval(params, rule->var), step);
1432}
1433
1434/**
1435 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1436 * @runtime: PCM runtime instance
1437 * @cond: condition bits
1438 * @var: hw_params variable to apply the step constraint
1439 * @step: step size
1440 *
1441 * Return: Zero if successful, or a negative error code on failure.
1442 */
1443int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1444			       unsigned int cond,
1445			       snd_pcm_hw_param_t var,
1446			       unsigned long step)
1447{
1448	return snd_pcm_hw_rule_add(runtime, cond, var, 
1449				   snd_pcm_hw_rule_step, (void *) step,
1450				   var, -1);
1451}
1452EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1453
1454static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1455{
1456	static const unsigned int pow2_sizes[] = {
1457		1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1458		1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1459		1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1460		1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1461	};
1462	return snd_interval_list(hw_param_interval(params, rule->var),
1463				 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1464}		
1465
1466/**
1467 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1468 * @runtime: PCM runtime instance
1469 * @cond: condition bits
1470 * @var: hw_params variable to apply the power-of-2 constraint
1471 *
1472 * Return: Zero if successful, or a negative error code on failure.
1473 */
1474int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1475			       unsigned int cond,
1476			       snd_pcm_hw_param_t var)
1477{
1478	return snd_pcm_hw_rule_add(runtime, cond, var, 
1479				   snd_pcm_hw_rule_pow2, NULL,
1480				   var, -1);
1481}
1482EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1483
1484static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1485					   struct snd_pcm_hw_rule *rule)
1486{
1487	unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1488	struct snd_interval *rate;
1489
1490	rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1491	return snd_interval_list(rate, 1, &base_rate, 0);
1492}
1493
1494/**
1495 * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1496 * @runtime: PCM runtime instance
1497 * @base_rate: the rate at which the hardware does not resample
1498 *
1499 * Return: Zero if successful, or a negative error code on failure.
1500 */
1501int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1502			       unsigned int base_rate)
1503{
1504	return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1505				   SNDRV_PCM_HW_PARAM_RATE,
1506				   snd_pcm_hw_rule_noresample_func,
1507				   (void *)(uintptr_t)base_rate,
1508				   SNDRV_PCM_HW_PARAM_RATE, -1);
1509}
1510EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1511
1512static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1513				  snd_pcm_hw_param_t var)
1514{
1515	if (hw_is_mask(var)) {
1516		snd_mask_any(hw_param_mask(params, var));
1517		params->cmask |= 1 << var;
1518		params->rmask |= 1 << var;
1519		return;
1520	}
1521	if (hw_is_interval(var)) {
1522		snd_interval_any(hw_param_interval(params, var));
1523		params->cmask |= 1 << var;
1524		params->rmask |= 1 << var;
1525		return;
1526	}
1527	snd_BUG();
1528}
1529
1530void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1531{
1532	unsigned int k;
1533	memset(params, 0, sizeof(*params));
1534	for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1535		_snd_pcm_hw_param_any(params, k);
1536	for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1537		_snd_pcm_hw_param_any(params, k);
1538	params->info = ~0U;
1539}
1540EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1541
1542/**
1543 * snd_pcm_hw_param_value - return @params field @var value
1544 * @params: the hw_params instance
1545 * @var: parameter to retrieve
1546 * @dir: pointer to the direction (-1,0,1) or %NULL
1547 *
1548 * Return: The value for field @var if it's fixed in configuration space
1549 * defined by @params. -%EINVAL otherwise.
1550 */
1551int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1552			   snd_pcm_hw_param_t var, int *dir)
1553{
1554	if (hw_is_mask(var)) {
1555		const struct snd_mask *mask = hw_param_mask_c(params, var);
1556		if (!snd_mask_single(mask))
1557			return -EINVAL;
1558		if (dir)
1559			*dir = 0;
1560		return snd_mask_value(mask);
1561	}
1562	if (hw_is_interval(var)) {
1563		const struct snd_interval *i = hw_param_interval_c(params, var);
1564		if (!snd_interval_single(i))
1565			return -EINVAL;
1566		if (dir)
1567			*dir = i->openmin;
1568		return snd_interval_value(i);
1569	}
1570	return -EINVAL;
1571}
1572EXPORT_SYMBOL(snd_pcm_hw_param_value);
1573
1574void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1575				snd_pcm_hw_param_t var)
1576{
1577	if (hw_is_mask(var)) {
1578		snd_mask_none(hw_param_mask(params, var));
1579		params->cmask |= 1 << var;
1580		params->rmask |= 1 << var;
1581	} else if (hw_is_interval(var)) {
1582		snd_interval_none(hw_param_interval(params, var));
1583		params->cmask |= 1 << var;
1584		params->rmask |= 1 << var;
1585	} else {
1586		snd_BUG();
1587	}
1588}
1589EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1590
1591static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1592				   snd_pcm_hw_param_t var)
1593{
1594	int changed;
1595	if (hw_is_mask(var))
1596		changed = snd_mask_refine_first(hw_param_mask(params, var));
1597	else if (hw_is_interval(var))
1598		changed = snd_interval_refine_first(hw_param_interval(params, var));
1599	else
1600		return -EINVAL;
1601	if (changed > 0) {
1602		params->cmask |= 1 << var;
1603		params->rmask |= 1 << var;
1604	}
1605	return changed;
1606}
1607
1608
1609/**
1610 * snd_pcm_hw_param_first - refine config space and return minimum value
1611 * @pcm: PCM instance
1612 * @params: the hw_params instance
1613 * @var: parameter to retrieve
1614 * @dir: pointer to the direction (-1,0,1) or %NULL
1615 *
1616 * Inside configuration space defined by @params remove from @var all
1617 * values > minimum. Reduce configuration space accordingly.
1618 *
1619 * Return: The minimum, or a negative error code on failure.
1620 */
1621int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm, 
1622			   struct snd_pcm_hw_params *params, 
1623			   snd_pcm_hw_param_t var, int *dir)
1624{
1625	int changed = _snd_pcm_hw_param_first(params, var);
1626	if (changed < 0)
1627		return changed;
1628	if (params->rmask) {
1629		int err = snd_pcm_hw_refine(pcm, params);
1630		if (err < 0)
1631			return err;
1632	}
1633	return snd_pcm_hw_param_value(params, var, dir);
1634}
1635EXPORT_SYMBOL(snd_pcm_hw_param_first);
1636
1637static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1638				  snd_pcm_hw_param_t var)
1639{
1640	int changed;
1641	if (hw_is_mask(var))
1642		changed = snd_mask_refine_last(hw_param_mask(params, var));
1643	else if (hw_is_interval(var))
1644		changed = snd_interval_refine_last(hw_param_interval(params, var));
1645	else
1646		return -EINVAL;
1647	if (changed > 0) {
1648		params->cmask |= 1 << var;
1649		params->rmask |= 1 << var;
1650	}
1651	return changed;
1652}
1653
1654
1655/**
1656 * snd_pcm_hw_param_last - refine config space and return maximum value
1657 * @pcm: PCM instance
1658 * @params: the hw_params instance
1659 * @var: parameter to retrieve
1660 * @dir: pointer to the direction (-1,0,1) or %NULL
1661 *
1662 * Inside configuration space defined by @params remove from @var all
1663 * values < maximum. Reduce configuration space accordingly.
1664 *
1665 * Return: The maximum, or a negative error code on failure.
1666 */
1667int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm, 
1668			  struct snd_pcm_hw_params *params,
1669			  snd_pcm_hw_param_t var, int *dir)
1670{
1671	int changed = _snd_pcm_hw_param_last(params, var);
1672	if (changed < 0)
1673		return changed;
1674	if (params->rmask) {
1675		int err = snd_pcm_hw_refine(pcm, params);
1676		if (err < 0)
1677			return err;
1678	}
1679	return snd_pcm_hw_param_value(params, var, dir);
1680}
1681EXPORT_SYMBOL(snd_pcm_hw_param_last);
1682
1683static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1684				   void *arg)
1685{
1686	struct snd_pcm_runtime *runtime = substream->runtime;
1687	unsigned long flags;
1688	snd_pcm_stream_lock_irqsave(substream, flags);
1689	if (snd_pcm_running(substream) &&
1690	    snd_pcm_update_hw_ptr(substream) >= 0)
1691		runtime->status->hw_ptr %= runtime->buffer_size;
1692	else {
1693		runtime->status->hw_ptr = 0;
1694		runtime->hw_ptr_wrap = 0;
1695	}
1696	snd_pcm_stream_unlock_irqrestore(substream, flags);
1697	return 0;
1698}
1699
1700static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1701					  void *arg)
1702{
1703	struct snd_pcm_channel_info *info = arg;
1704	struct snd_pcm_runtime *runtime = substream->runtime;
1705	int width;
1706	if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1707		info->offset = -1;
1708		return 0;
1709	}
1710	width = snd_pcm_format_physical_width(runtime->format);
1711	if (width < 0)
1712		return width;
1713	info->offset = 0;
1714	switch (runtime->access) {
1715	case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1716	case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1717		info->first = info->channel * width;
1718		info->step = runtime->channels * width;
1719		break;
1720	case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1721	case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1722	{
1723		size_t size = runtime->dma_bytes / runtime->channels;
1724		info->first = info->channel * size * 8;
1725		info->step = width;
1726		break;
1727	}
1728	default:
1729		snd_BUG();
1730		break;
1731	}
1732	return 0;
1733}
1734
1735static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1736				       void *arg)
1737{
1738	struct snd_pcm_hw_params *params = arg;
1739	snd_pcm_format_t format;
1740	int channels;
1741	ssize_t frame_size;
1742
1743	params->fifo_size = substream->runtime->hw.fifo_size;
1744	if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1745		format = params_format(params);
1746		channels = params_channels(params);
1747		frame_size = snd_pcm_format_size(format, channels);
1748		if (frame_size > 0)
1749			params->fifo_size /= (unsigned)frame_size;
1750	}
1751	return 0;
1752}
1753
1754/**
1755 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1756 * @substream: the pcm substream instance
1757 * @cmd: ioctl command
1758 * @arg: ioctl argument
1759 *
1760 * Processes the generic ioctl commands for PCM.
1761 * Can be passed as the ioctl callback for PCM ops.
1762 *
1763 * Return: Zero if successful, or a negative error code on failure.
1764 */
1765int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1766		      unsigned int cmd, void *arg)
1767{
1768	switch (cmd) {
1769	case SNDRV_PCM_IOCTL1_RESET:
1770		return snd_pcm_lib_ioctl_reset(substream, arg);
1771	case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1772		return snd_pcm_lib_ioctl_channel_info(substream, arg);
1773	case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1774		return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1775	}
1776	return -ENXIO;
1777}
1778EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1779
1780/**
1781 * snd_pcm_period_elapsed - update the pcm status for the next period
1782 * @substream: the pcm substream instance
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1783 *
1784 * This function is called from the interrupt handler when the
1785 * PCM has processed the period size.  It will update the current
1786 * pointer, wake up sleepers, etc.
1787 *
1788 * Even if more than one periods have elapsed since the last call, you
1789 * have to call this only once.
1790 */
1791void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1792{
1793	struct snd_pcm_runtime *runtime;
1794	unsigned long flags;
1795
1796	if (snd_BUG_ON(!substream))
1797		return;
1798
1799	snd_pcm_stream_lock_irqsave(substream, flags);
1800	if (PCM_RUNTIME_CHECK(substream))
1801		goto _unlock;
1802	runtime = substream->runtime;
1803
1804	if (!snd_pcm_running(substream) ||
1805	    snd_pcm_update_hw_ptr0(substream, 1) < 0)
1806		goto _end;
1807
1808#ifdef CONFIG_SND_PCM_TIMER
1809	if (substream->timer_running)
1810		snd_timer_interrupt(substream->timer, 1);
1811#endif
1812 _end:
1813	kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1814 _unlock:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1815	snd_pcm_stream_unlock_irqrestore(substream, flags);
1816}
1817EXPORT_SYMBOL(snd_pcm_period_elapsed);
1818
1819/*
1820 * Wait until avail_min data becomes available
1821 * Returns a negative error code if any error occurs during operation.
1822 * The available space is stored on availp.  When err = 0 and avail = 0
1823 * on the capture stream, it indicates the stream is in DRAINING state.
1824 */
1825static int wait_for_avail(struct snd_pcm_substream *substream,
1826			      snd_pcm_uframes_t *availp)
1827{
1828	struct snd_pcm_runtime *runtime = substream->runtime;
1829	int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1830	wait_queue_entry_t wait;
1831	int err = 0;
1832	snd_pcm_uframes_t avail = 0;
1833	long wait_time, tout;
1834
1835	init_waitqueue_entry(&wait, current);
1836	set_current_state(TASK_INTERRUPTIBLE);
1837	add_wait_queue(&runtime->tsleep, &wait);
1838
1839	if (runtime->no_period_wakeup)
1840		wait_time = MAX_SCHEDULE_TIMEOUT;
1841	else {
1842		/* use wait time from substream if available */
1843		if (substream->wait_time) {
1844			wait_time = substream->wait_time;
1845		} else {
1846			wait_time = 10;
1847
1848			if (runtime->rate) {
1849				long t = runtime->period_size * 2 /
1850					 runtime->rate;
1851				wait_time = max(t, wait_time);
1852			}
1853			wait_time = msecs_to_jiffies(wait_time * 1000);
1854		}
1855	}
1856
1857	for (;;) {
1858		if (signal_pending(current)) {
1859			err = -ERESTARTSYS;
1860			break;
1861		}
1862
1863		/*
1864		 * We need to check if space became available already
1865		 * (and thus the wakeup happened already) first to close
1866		 * the race of space already having become available.
1867		 * This check must happen after been added to the waitqueue
1868		 * and having current state be INTERRUPTIBLE.
1869		 */
1870		avail = snd_pcm_avail(substream);
1871		if (avail >= runtime->twake)
1872			break;
1873		snd_pcm_stream_unlock_irq(substream);
1874
1875		tout = schedule_timeout(wait_time);
1876
1877		snd_pcm_stream_lock_irq(substream);
1878		set_current_state(TASK_INTERRUPTIBLE);
1879		switch (runtime->status->state) {
1880		case SNDRV_PCM_STATE_SUSPENDED:
1881			err = -ESTRPIPE;
1882			goto _endloop;
1883		case SNDRV_PCM_STATE_XRUN:
1884			err = -EPIPE;
1885			goto _endloop;
1886		case SNDRV_PCM_STATE_DRAINING:
1887			if (is_playback)
1888				err = -EPIPE;
1889			else 
1890				avail = 0; /* indicate draining */
1891			goto _endloop;
1892		case SNDRV_PCM_STATE_OPEN:
1893		case SNDRV_PCM_STATE_SETUP:
1894		case SNDRV_PCM_STATE_DISCONNECTED:
1895			err = -EBADFD;
1896			goto _endloop;
1897		case SNDRV_PCM_STATE_PAUSED:
1898			continue;
1899		}
1900		if (!tout) {
1901			pcm_dbg(substream->pcm,
1902				"%s write error (DMA or IRQ trouble?)\n",
1903				is_playback ? "playback" : "capture");
1904			err = -EIO;
1905			break;
1906		}
1907	}
1908 _endloop:
1909	set_current_state(TASK_RUNNING);
1910	remove_wait_queue(&runtime->tsleep, &wait);
1911	*availp = avail;
1912	return err;
1913}
1914	
1915typedef int (*pcm_transfer_f)(struct snd_pcm_substream *substream,
1916			      int channel, unsigned long hwoff,
1917			      void *buf, unsigned long bytes);
1918
1919typedef int (*pcm_copy_f)(struct snd_pcm_substream *, snd_pcm_uframes_t, void *,
1920			  snd_pcm_uframes_t, snd_pcm_uframes_t, pcm_transfer_f);
1921
1922/* calculate the target DMA-buffer position to be written/read */
1923static void *get_dma_ptr(struct snd_pcm_runtime *runtime,
1924			   int channel, unsigned long hwoff)
1925{
1926	return runtime->dma_area + hwoff +
1927		channel * (runtime->dma_bytes / runtime->channels);
1928}
1929
1930/* default copy_user ops for write; used for both interleaved and non- modes */
1931static int default_write_copy(struct snd_pcm_substream *substream,
1932			      int channel, unsigned long hwoff,
1933			      void *buf, unsigned long bytes)
1934{
1935	if (copy_from_user(get_dma_ptr(substream->runtime, channel, hwoff),
1936			   (void __user *)buf, bytes))
1937		return -EFAULT;
1938	return 0;
1939}
1940
1941/* default copy_kernel ops for write */
1942static int default_write_copy_kernel(struct snd_pcm_substream *substream,
1943				     int channel, unsigned long hwoff,
1944				     void *buf, unsigned long bytes)
1945{
1946	memcpy(get_dma_ptr(substream->runtime, channel, hwoff), buf, bytes);
1947	return 0;
1948}
1949
1950/* fill silence instead of copy data; called as a transfer helper
1951 * from __snd_pcm_lib_write() or directly from noninterleaved_copy() when
1952 * a NULL buffer is passed
1953 */
1954static int fill_silence(struct snd_pcm_substream *substream, int channel,
1955			unsigned long hwoff, void *buf, unsigned long bytes)
1956{
1957	struct snd_pcm_runtime *runtime = substream->runtime;
1958
1959	if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
1960		return 0;
1961	if (substream->ops->fill_silence)
1962		return substream->ops->fill_silence(substream, channel,
1963						    hwoff, bytes);
1964
1965	snd_pcm_format_set_silence(runtime->format,
1966				   get_dma_ptr(runtime, channel, hwoff),
1967				   bytes_to_samples(runtime, bytes));
1968	return 0;
1969}
1970
1971/* default copy_user ops for read; used for both interleaved and non- modes */
1972static int default_read_copy(struct snd_pcm_substream *substream,
1973			     int channel, unsigned long hwoff,
1974			     void *buf, unsigned long bytes)
1975{
1976	if (copy_to_user((void __user *)buf,
1977			 get_dma_ptr(substream->runtime, channel, hwoff),
1978			 bytes))
1979		return -EFAULT;
1980	return 0;
1981}
1982
1983/* default copy_kernel ops for read */
1984static int default_read_copy_kernel(struct snd_pcm_substream *substream,
1985				    int channel, unsigned long hwoff,
1986				    void *buf, unsigned long bytes)
1987{
1988	memcpy(buf, get_dma_ptr(substream->runtime, channel, hwoff), bytes);
1989	return 0;
1990}
1991
1992/* call transfer function with the converted pointers and sizes;
1993 * for interleaved mode, it's one shot for all samples
1994 */
1995static int interleaved_copy(struct snd_pcm_substream *substream,
1996			    snd_pcm_uframes_t hwoff, void *data,
1997			    snd_pcm_uframes_t off,
1998			    snd_pcm_uframes_t frames,
1999			    pcm_transfer_f transfer)
2000{
2001	struct snd_pcm_runtime *runtime = substream->runtime;
2002
2003	/* convert to bytes */
2004	hwoff = frames_to_bytes(runtime, hwoff);
2005	off = frames_to_bytes(runtime, off);
2006	frames = frames_to_bytes(runtime, frames);
2007	return transfer(substream, 0, hwoff, data + off, frames);
2008}
2009
2010/* call transfer function with the converted pointers and sizes for each
2011 * non-interleaved channel; when buffer is NULL, silencing instead of copying
2012 */
2013static int noninterleaved_copy(struct snd_pcm_substream *substream,
2014			       snd_pcm_uframes_t hwoff, void *data,
2015			       snd_pcm_uframes_t off,
2016			       snd_pcm_uframes_t frames,
2017			       pcm_transfer_f transfer)
2018{
2019	struct snd_pcm_runtime *runtime = substream->runtime;
2020	int channels = runtime->channels;
2021	void **bufs = data;
2022	int c, err;
2023
2024	/* convert to bytes; note that it's not frames_to_bytes() here.
2025	 * in non-interleaved mode, we copy for each channel, thus
2026	 * each copy is n_samples bytes x channels = whole frames.
2027	 */
2028	off = samples_to_bytes(runtime, off);
2029	frames = samples_to_bytes(runtime, frames);
2030	hwoff = samples_to_bytes(runtime, hwoff);
2031	for (c = 0; c < channels; ++c, ++bufs) {
2032		if (!data || !*bufs)
2033			err = fill_silence(substream, c, hwoff, NULL, frames);
2034		else
2035			err = transfer(substream, c, hwoff, *bufs + off,
2036				       frames);
2037		if (err < 0)
2038			return err;
2039	}
2040	return 0;
2041}
2042
2043/* fill silence on the given buffer position;
2044 * called from snd_pcm_playback_silence()
2045 */
2046static int fill_silence_frames(struct snd_pcm_substream *substream,
2047			       snd_pcm_uframes_t off, snd_pcm_uframes_t frames)
2048{
2049	if (substream->runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
2050	    substream->runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED)
2051		return interleaved_copy(substream, off, NULL, 0, frames,
2052					fill_silence);
2053	else
2054		return noninterleaved_copy(substream, off, NULL, 0, frames,
2055					   fill_silence);
2056}
2057
2058/* sanity-check for read/write methods */
2059static int pcm_sanity_check(struct snd_pcm_substream *substream)
2060{
2061	struct snd_pcm_runtime *runtime;
2062	if (PCM_RUNTIME_CHECK(substream))
2063		return -ENXIO;
2064	runtime = substream->runtime;
2065	if (snd_BUG_ON(!substream->ops->copy_user && !runtime->dma_area))
2066		return -EINVAL;
2067	if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2068		return -EBADFD;
2069	return 0;
2070}
2071
2072static int pcm_accessible_state(struct snd_pcm_runtime *runtime)
2073{
2074	switch (runtime->status->state) {
2075	case SNDRV_PCM_STATE_PREPARED:
2076	case SNDRV_PCM_STATE_RUNNING:
2077	case SNDRV_PCM_STATE_PAUSED:
2078		return 0;
2079	case SNDRV_PCM_STATE_XRUN:
2080		return -EPIPE;
2081	case SNDRV_PCM_STATE_SUSPENDED:
2082		return -ESTRPIPE;
2083	default:
2084		return -EBADFD;
2085	}
2086}
2087
2088/* update to the given appl_ptr and call ack callback if needed;
2089 * when an error is returned, take back to the original value
2090 */
2091int pcm_lib_apply_appl_ptr(struct snd_pcm_substream *substream,
2092			   snd_pcm_uframes_t appl_ptr)
2093{
2094	struct snd_pcm_runtime *runtime = substream->runtime;
2095	snd_pcm_uframes_t old_appl_ptr = runtime->control->appl_ptr;
 
2096	int ret;
2097
2098	if (old_appl_ptr == appl_ptr)
2099		return 0;
2100
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2101	runtime->control->appl_ptr = appl_ptr;
2102	if (substream->ops->ack) {
2103		ret = substream->ops->ack(substream);
2104		if (ret < 0) {
2105			runtime->control->appl_ptr = old_appl_ptr;
2106			return ret;
2107		}
2108	}
2109
2110	trace_applptr(substream, old_appl_ptr, appl_ptr);
2111
2112	return 0;
2113}
2114
2115/* the common loop for read/write data */
2116snd_pcm_sframes_t __snd_pcm_lib_xfer(struct snd_pcm_substream *substream,
2117				     void *data, bool interleaved,
2118				     snd_pcm_uframes_t size, bool in_kernel)
2119{
2120	struct snd_pcm_runtime *runtime = substream->runtime;
2121	snd_pcm_uframes_t xfer = 0;
2122	snd_pcm_uframes_t offset = 0;
2123	snd_pcm_uframes_t avail;
2124	pcm_copy_f writer;
2125	pcm_transfer_f transfer;
2126	bool nonblock;
2127	bool is_playback;
2128	int err;
2129
2130	err = pcm_sanity_check(substream);
2131	if (err < 0)
2132		return err;
2133
2134	is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
2135	if (interleaved) {
2136		if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2137		    runtime->channels > 1)
2138			return -EINVAL;
2139		writer = interleaved_copy;
2140	} else {
2141		if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2142			return -EINVAL;
2143		writer = noninterleaved_copy;
2144	}
2145
2146	if (!data) {
2147		if (is_playback)
2148			transfer = fill_silence;
2149		else
2150			return -EINVAL;
2151	} else if (in_kernel) {
2152		if (substream->ops->copy_kernel)
2153			transfer = substream->ops->copy_kernel;
2154		else
2155			transfer = is_playback ?
2156				default_write_copy_kernel : default_read_copy_kernel;
2157	} else {
2158		if (substream->ops->copy_user)
2159			transfer = (pcm_transfer_f)substream->ops->copy_user;
2160		else
2161			transfer = is_playback ?
2162				default_write_copy : default_read_copy;
2163	}
2164
2165	if (size == 0)
2166		return 0;
2167
2168	nonblock = !!(substream->f_flags & O_NONBLOCK);
2169
2170	snd_pcm_stream_lock_irq(substream);
2171	err = pcm_accessible_state(runtime);
2172	if (err < 0)
2173		goto _end_unlock;
2174
2175	runtime->twake = runtime->control->avail_min ? : 1;
2176	if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2177		snd_pcm_update_hw_ptr(substream);
2178
2179	/*
2180	 * If size < start_threshold, wait indefinitely. Another
2181	 * thread may start capture
2182	 */
2183	if (!is_playback &&
2184	    runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2185	    size >= runtime->start_threshold) {
2186		err = snd_pcm_start(substream);
2187		if (err < 0)
2188			goto _end_unlock;
2189	}
2190
2191	avail = snd_pcm_avail(substream);
2192
2193	while (size > 0) {
2194		snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2195		snd_pcm_uframes_t cont;
2196		if (!avail) {
2197			if (!is_playback &&
2198			    runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
2199				snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2200				goto _end_unlock;
2201			}
2202			if (nonblock) {
2203				err = -EAGAIN;
2204				goto _end_unlock;
2205			}
2206			runtime->twake = min_t(snd_pcm_uframes_t, size,
2207					runtime->control->avail_min ? : 1);
2208			err = wait_for_avail(substream, &avail);
2209			if (err < 0)
2210				goto _end_unlock;
2211			if (!avail)
2212				continue; /* draining */
2213		}
2214		frames = size > avail ? avail : size;
2215		appl_ptr = READ_ONCE(runtime->control->appl_ptr);
2216		appl_ofs = appl_ptr % runtime->buffer_size;
2217		cont = runtime->buffer_size - appl_ofs;
2218		if (frames > cont)
2219			frames = cont;
2220		if (snd_BUG_ON(!frames)) {
2221			err = -EINVAL;
2222			goto _end_unlock;
2223		}
 
 
 
 
2224		snd_pcm_stream_unlock_irq(substream);
 
 
2225		err = writer(substream, appl_ofs, data, offset, frames,
2226			     transfer);
 
 
2227		snd_pcm_stream_lock_irq(substream);
 
2228		if (err < 0)
2229			goto _end_unlock;
2230		err = pcm_accessible_state(runtime);
2231		if (err < 0)
2232			goto _end_unlock;
2233		appl_ptr += frames;
2234		if (appl_ptr >= runtime->boundary)
2235			appl_ptr -= runtime->boundary;
2236		err = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2237		if (err < 0)
2238			goto _end_unlock;
2239
2240		offset += frames;
2241		size -= frames;
2242		xfer += frames;
2243		avail -= frames;
2244		if (is_playback &&
2245		    runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2246		    snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2247			err = snd_pcm_start(substream);
2248			if (err < 0)
2249				goto _end_unlock;
2250		}
2251	}
2252 _end_unlock:
2253	runtime->twake = 0;
2254	if (xfer > 0 && err >= 0)
2255		snd_pcm_update_state(substream, runtime);
2256	snd_pcm_stream_unlock_irq(substream);
2257	return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2258}
2259EXPORT_SYMBOL(__snd_pcm_lib_xfer);
2260
2261/*
2262 * standard channel mapping helpers
2263 */
2264
2265/* default channel maps for multi-channel playbacks, up to 8 channels */
2266const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2267	{ .channels = 1,
2268	  .map = { SNDRV_CHMAP_MONO } },
2269	{ .channels = 2,
2270	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2271	{ .channels = 4,
2272	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2273		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2274	{ .channels = 6,
2275	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2276		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2277		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2278	{ .channels = 8,
2279	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2280		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2281		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2282		   SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2283	{ }
2284};
2285EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2286
2287/* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2288const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2289	{ .channels = 1,
2290	  .map = { SNDRV_CHMAP_MONO } },
2291	{ .channels = 2,
2292	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2293	{ .channels = 4,
2294	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2295		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2296	{ .channels = 6,
2297	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2298		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2299		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2300	{ .channels = 8,
2301	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2302		   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2303		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2304		   SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2305	{ }
2306};
2307EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2308
2309static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2310{
2311	if (ch > info->max_channels)
2312		return false;
2313	return !info->channel_mask || (info->channel_mask & (1U << ch));
2314}
2315
2316static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2317			      struct snd_ctl_elem_info *uinfo)
2318{
2319	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2320
2321	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2322	uinfo->count = info->max_channels;
2323	uinfo->value.integer.min = 0;
2324	uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2325	return 0;
2326}
2327
2328/* get callback for channel map ctl element
2329 * stores the channel position firstly matching with the current channels
2330 */
2331static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2332			     struct snd_ctl_elem_value *ucontrol)
2333{
2334	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2335	unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2336	struct snd_pcm_substream *substream;
2337	const struct snd_pcm_chmap_elem *map;
2338
2339	if (!info->chmap)
2340		return -EINVAL;
2341	substream = snd_pcm_chmap_substream(info, idx);
2342	if (!substream)
2343		return -ENODEV;
2344	memset(ucontrol->value.integer.value, 0,
2345	       sizeof(long) * info->max_channels);
2346	if (!substream->runtime)
2347		return 0; /* no channels set */
2348	for (map = info->chmap; map->channels; map++) {
2349		int i;
2350		if (map->channels == substream->runtime->channels &&
2351		    valid_chmap_channels(info, map->channels)) {
2352			for (i = 0; i < map->channels; i++)
2353				ucontrol->value.integer.value[i] = map->map[i];
2354			return 0;
2355		}
2356	}
2357	return -EINVAL;
2358}
2359
2360/* tlv callback for channel map ctl element
2361 * expands the pre-defined channel maps in a form of TLV
2362 */
2363static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2364			     unsigned int size, unsigned int __user *tlv)
2365{
2366	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2367	const struct snd_pcm_chmap_elem *map;
2368	unsigned int __user *dst;
2369	int c, count = 0;
2370
2371	if (!info->chmap)
2372		return -EINVAL;
2373	if (size < 8)
2374		return -ENOMEM;
2375	if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2376		return -EFAULT;
2377	size -= 8;
2378	dst = tlv + 2;
2379	for (map = info->chmap; map->channels; map++) {
2380		int chs_bytes = map->channels * 4;
2381		if (!valid_chmap_channels(info, map->channels))
2382			continue;
2383		if (size < 8)
2384			return -ENOMEM;
2385		if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2386		    put_user(chs_bytes, dst + 1))
2387			return -EFAULT;
2388		dst += 2;
2389		size -= 8;
2390		count += 8;
2391		if (size < chs_bytes)
2392			return -ENOMEM;
2393		size -= chs_bytes;
2394		count += chs_bytes;
2395		for (c = 0; c < map->channels; c++) {
2396			if (put_user(map->map[c], dst))
2397				return -EFAULT;
2398			dst++;
2399		}
2400	}
2401	if (put_user(count, tlv + 1))
2402		return -EFAULT;
2403	return 0;
2404}
2405
2406static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2407{
2408	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2409	info->pcm->streams[info->stream].chmap_kctl = NULL;
2410	kfree(info);
2411}
2412
2413/**
2414 * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2415 * @pcm: the assigned PCM instance
2416 * @stream: stream direction
2417 * @chmap: channel map elements (for query)
2418 * @max_channels: the max number of channels for the stream
2419 * @private_value: the value passed to each kcontrol's private_value field
2420 * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2421 *
2422 * Create channel-mapping control elements assigned to the given PCM stream(s).
2423 * Return: Zero if successful, or a negative error value.
2424 */
2425int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2426			   const struct snd_pcm_chmap_elem *chmap,
2427			   int max_channels,
2428			   unsigned long private_value,
2429			   struct snd_pcm_chmap **info_ret)
2430{
2431	struct snd_pcm_chmap *info;
2432	struct snd_kcontrol_new knew = {
2433		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
2434		.access = SNDRV_CTL_ELEM_ACCESS_READ |
2435			SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2436			SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2437		.info = pcm_chmap_ctl_info,
2438		.get = pcm_chmap_ctl_get,
2439		.tlv.c = pcm_chmap_ctl_tlv,
2440	};
2441	int err;
2442
2443	if (WARN_ON(pcm->streams[stream].chmap_kctl))
2444		return -EBUSY;
2445	info = kzalloc(sizeof(*info), GFP_KERNEL);
2446	if (!info)
2447		return -ENOMEM;
2448	info->pcm = pcm;
2449	info->stream = stream;
2450	info->chmap = chmap;
2451	info->max_channels = max_channels;
2452	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2453		knew.name = "Playback Channel Map";
2454	else
2455		knew.name = "Capture Channel Map";
2456	knew.device = pcm->device;
2457	knew.count = pcm->streams[stream].substream_count;
2458	knew.private_value = private_value;
2459	info->kctl = snd_ctl_new1(&knew, info);
2460	if (!info->kctl) {
2461		kfree(info);
2462		return -ENOMEM;
2463	}
2464	info->kctl->private_free = pcm_chmap_ctl_private_free;
2465	err = snd_ctl_add(pcm->card, info->kctl);
2466	if (err < 0)
2467		return err;
2468	pcm->streams[stream].chmap_kctl = info->kctl;
2469	if (info_ret)
2470		*info_ret = info;
2471	return 0;
2472}
2473EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);