linux/sound/core/pcm_lib.c
<<
>>
Prefs
   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                snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 149        snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 150        if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
 151                char name[16];
 152                snd_pcm_debug_name(substream, name, sizeof(name));
 153                pcm_warn(substream->pcm, "XRUN: %s\n", name);
 154                dump_stack_on_xrun(substream);
 155        }
 156}
 157
 158#ifdef CONFIG_SND_PCM_XRUN_DEBUG
 159#define hw_ptr_error(substream, in_interrupt, reason, fmt, args...)     \
 160        do {                                                            \
 161                trace_hw_ptr_error(substream, reason);  \
 162                if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {          \
 163                        pr_err_ratelimited("ALSA: PCM: [%c] " reason ": " fmt, \
 164                                           (in_interrupt) ? 'Q' : 'P', ##args); \
 165                        dump_stack_on_xrun(substream);                  \
 166                }                                                       \
 167        } while (0)
 168
 169#else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
 170
 171#define hw_ptr_error(substream, fmt, args...) do { } while (0)
 172
 173#endif
 174
 175int snd_pcm_update_state(struct snd_pcm_substream *substream,
 176                         struct snd_pcm_runtime *runtime)
 177{
 178        snd_pcm_uframes_t avail;
 179
 180        avail = snd_pcm_avail(substream);
 181        if (avail > runtime->avail_max)
 182                runtime->avail_max = avail;
 183        if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
 184                if (avail >= runtime->buffer_size) {
 185                        snd_pcm_drain_done(substream);
 186                        return -EPIPE;
 187                }
 188        } else {
 189                if (avail >= runtime->stop_threshold) {
 190                        __snd_pcm_xrun(substream);
 191                        return -EPIPE;
 192                }
 193        }
 194        if (runtime->twake) {
 195                if (avail >= runtime->twake)
 196                        wake_up(&runtime->tsleep);
 197        } else if (avail >= runtime->control->avail_min)
 198                wake_up(&runtime->sleep);
 199        return 0;
 200}
 201
 202static void update_audio_tstamp(struct snd_pcm_substream *substream,
 203                                struct timespec *curr_tstamp,
 204                                struct timespec *audio_tstamp)
 205{
 206        struct snd_pcm_runtime *runtime = substream->runtime;
 207        u64 audio_frames, audio_nsecs;
 208        struct timespec driver_tstamp;
 209
 210        if (runtime->tstamp_mode != SNDRV_PCM_TSTAMP_ENABLE)
 211                return;
 212
 213        if (!(substream->ops->get_time_info) ||
 214                (runtime->audio_tstamp_report.actual_type ==
 215                        SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
 216
 217                /*
 218                 * provide audio timestamp derived from pointer position
 219                 * add delay only if requested
 220                 */
 221
 222                audio_frames = runtime->hw_ptr_wrap + runtime->status->hw_ptr;
 223
 224                if (runtime->audio_tstamp_config.report_delay) {
 225                        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 226                                audio_frames -=  runtime->delay;
 227                        else
 228                                audio_frames +=  runtime->delay;
 229                }
 230                audio_nsecs = div_u64(audio_frames * 1000000000LL,
 231                                runtime->rate);
 232                *audio_tstamp = ns_to_timespec(audio_nsecs);
 233        }
 234        if (!timespec_equal(&runtime->status->audio_tstamp, audio_tstamp)) {
 235                runtime->status->audio_tstamp = *audio_tstamp;
 236                runtime->status->tstamp = *curr_tstamp;
 237        }
 238
 239        /*
 240         * re-take a driver timestamp to let apps detect if the reference tstamp
 241         * read by low-level hardware was provided with a delay
 242         */
 243        snd_pcm_gettime(substream->runtime, (struct timespec *)&driver_tstamp);
 244        runtime->driver_tstamp = driver_tstamp;
 245}
 246
 247static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
 248                                  unsigned int in_interrupt)
 249{
 250        struct snd_pcm_runtime *runtime = substream->runtime;
 251        snd_pcm_uframes_t pos;
 252        snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
 253        snd_pcm_sframes_t hdelta, delta;
 254        unsigned long jdelta;
 255        unsigned long curr_jiffies;
 256        struct timespec curr_tstamp;
 257        struct timespec audio_tstamp;
 258        int crossed_boundary = 0;
 259
 260        old_hw_ptr = runtime->status->hw_ptr;
 261
 262        /*
 263         * group pointer, time and jiffies reads to allow for more
 264         * accurate correlations/corrections.
 265         * The values are stored at the end of this routine after
 266         * corrections for hw_ptr position
 267         */
 268        pos = substream->ops->pointer(substream);
 269        curr_jiffies = jiffies;
 270        if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
 271                if ((substream->ops->get_time_info) &&
 272                        (runtime->audio_tstamp_config.type_requested != SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
 273                        substream->ops->get_time_info(substream, &curr_tstamp,
 274                                                &audio_tstamp,
 275                                                &runtime->audio_tstamp_config,
 276                                                &runtime->audio_tstamp_report);
 277
 278                        /* re-test in case tstamp type is not supported in hardware and was demoted to DEFAULT */
 279                        if (runtime->audio_tstamp_report.actual_type == SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)
 280                                snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
 281                } else
 282                        snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
 283        }
 284
 285        if (pos == SNDRV_PCM_POS_XRUN) {
 286                __snd_pcm_xrun(substream);
 287                return -EPIPE;
 288        }
 289        if (pos >= runtime->buffer_size) {
 290                if (printk_ratelimit()) {
 291                        char name[16];
 292                        snd_pcm_debug_name(substream, name, sizeof(name));
 293                        pcm_err(substream->pcm,
 294                                "invalid position: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
 295                                name, pos, runtime->buffer_size,
 296                                runtime->period_size);
 297                }
 298                pos = 0;
 299        }
 300        pos -= pos % runtime->min_align;
 301        trace_hwptr(substream, pos, in_interrupt);
 302        hw_base = runtime->hw_ptr_base;
 303        new_hw_ptr = hw_base + pos;
 304        if (in_interrupt) {
 305                /* we know that one period was processed */
 306                /* delta = "expected next hw_ptr" for in_interrupt != 0 */
 307                delta = runtime->hw_ptr_interrupt + runtime->period_size;
 308                if (delta > new_hw_ptr) {
 309                        /* check for double acknowledged interrupts */
 310                        hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 311                        if (hdelta > runtime->hw_ptr_buffer_jiffies/2 + 1) {
 312                                hw_base += runtime->buffer_size;
 313                                if (hw_base >= runtime->boundary) {
 314                                        hw_base = 0;
 315                                        crossed_boundary++;
 316                                }
 317                                new_hw_ptr = hw_base + pos;
 318                                goto __delta;
 319                        }
 320                }
 321        }
 322        /* new_hw_ptr might be lower than old_hw_ptr in case when */
 323        /* pointer crosses the end of the ring buffer */
 324        if (new_hw_ptr < old_hw_ptr) {
 325                hw_base += runtime->buffer_size;
 326                if (hw_base >= runtime->boundary) {
 327                        hw_base = 0;
 328                        crossed_boundary++;
 329                }
 330                new_hw_ptr = hw_base + pos;
 331        }
 332      __delta:
 333        delta = new_hw_ptr - old_hw_ptr;
 334        if (delta < 0)
 335                delta += runtime->boundary;
 336
 337        if (runtime->no_period_wakeup) {
 338                snd_pcm_sframes_t xrun_threshold;
 339                /*
 340                 * Without regular period interrupts, we have to check
 341                 * the elapsed time to detect xruns.
 342                 */
 343                jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 344                if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
 345                        goto no_delta_check;
 346                hdelta = jdelta - delta * HZ / runtime->rate;
 347                xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
 348                while (hdelta > xrun_threshold) {
 349                        delta += runtime->buffer_size;
 350                        hw_base += runtime->buffer_size;
 351                        if (hw_base >= runtime->boundary) {
 352                                hw_base = 0;
 353                                crossed_boundary++;
 354                        }
 355                        new_hw_ptr = hw_base + pos;
 356                        hdelta -= runtime->hw_ptr_buffer_jiffies;
 357                }
 358                goto no_delta_check;
 359        }
 360
 361        /* something must be really wrong */
 362        if (delta >= runtime->buffer_size + runtime->period_size) {
 363                hw_ptr_error(substream, in_interrupt, "Unexpected hw_ptr",
 364                             "(stream=%i, pos=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
 365                             substream->stream, (long)pos,
 366                             (long)new_hw_ptr, (long)old_hw_ptr);
 367                return 0;
 368        }
 369
 370        /* Do jiffies check only in xrun_debug mode */
 371        if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
 372                goto no_jiffies_check;
 373
 374        /* Skip the jiffies check for hardwares with BATCH flag.
 375         * Such hardware usually just increases the position at each IRQ,
 376         * thus it can't give any strange position.
 377         */
 378        if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
 379                goto no_jiffies_check;
 380        hdelta = delta;
 381        if (hdelta < runtime->delay)
 382                goto no_jiffies_check;
 383        hdelta -= runtime->delay;
 384        jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 385        if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
 386                delta = jdelta /
 387                        (((runtime->period_size * HZ) / runtime->rate)
 388                                                                + HZ/100);
 389                /* move new_hw_ptr according jiffies not pos variable */
 390                new_hw_ptr = old_hw_ptr;
 391                hw_base = delta;
 392                /* use loop to avoid checks for delta overflows */
 393                /* the delta value is small or zero in most cases */
 394                while (delta > 0) {
 395                        new_hw_ptr += runtime->period_size;
 396                        if (new_hw_ptr >= runtime->boundary) {
 397                                new_hw_ptr -= runtime->boundary;
 398                                crossed_boundary--;
 399                        }
 400                        delta--;
 401                }
 402                /* align hw_base to buffer_size */
 403                hw_ptr_error(substream, in_interrupt, "hw_ptr skipping",
 404                             "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
 405                             (long)pos, (long)hdelta,
 406                             (long)runtime->period_size, jdelta,
 407                             ((hdelta * HZ) / runtime->rate), hw_base,
 408                             (unsigned long)old_hw_ptr,
 409                             (unsigned long)new_hw_ptr);
 410                /* reset values to proper state */
 411                delta = 0;
 412                hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
 413        }
 414 no_jiffies_check:
 415        if (delta > runtime->period_size + runtime->period_size / 2) {
 416                hw_ptr_error(substream, in_interrupt,
 417                             "Lost interrupts?",
 418                             "(stream=%i, delta=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
 419                             substream->stream, (long)delta,
 420                             (long)new_hw_ptr,
 421                             (long)old_hw_ptr);
 422        }
 423
 424 no_delta_check:
 425        if (runtime->status->hw_ptr == new_hw_ptr) {
 426                update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
 427                return 0;
 428        }
 429
 430        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 431            runtime->silence_size > 0)
 432                snd_pcm_playback_silence(substream, new_hw_ptr);
 433
 434        if (in_interrupt) {
 435                delta = new_hw_ptr - runtime->hw_ptr_interrupt;
 436                if (delta < 0)
 437                        delta += runtime->boundary;
 438                delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
 439                runtime->hw_ptr_interrupt += delta;
 440                if (runtime->hw_ptr_interrupt >= runtime->boundary)
 441                        runtime->hw_ptr_interrupt -= runtime->boundary;
 442        }
 443        runtime->hw_ptr_base = hw_base;
 444        runtime->status->hw_ptr = new_hw_ptr;
 445        runtime->hw_ptr_jiffies = curr_jiffies;
 446        if (crossed_boundary) {
 447                snd_BUG_ON(crossed_boundary != 1);
 448                runtime->hw_ptr_wrap += runtime->boundary;
 449        }
 450
 451        update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
 452
 453        return snd_pcm_update_state(substream, runtime);
 454}
 455
 456/* CAUTION: call it with irq disabled */
 457int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
 458{
 459        return snd_pcm_update_hw_ptr0(substream, 0);
 460}
 461
 462/**
 463 * snd_pcm_set_ops - set the PCM operators
 464 * @pcm: the pcm instance
 465 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
 466 * @ops: the operator table
 467 *
 468 * Sets the given PCM operators to the pcm instance.
 469 */
 470void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
 471                     const struct snd_pcm_ops *ops)
 472{
 473        struct snd_pcm_str *stream = &pcm->streams[direction];
 474        struct snd_pcm_substream *substream;
 475        
 476        for (substream = stream->substream; substream != NULL; substream = substream->next)
 477                substream->ops = ops;
 478}
 479EXPORT_SYMBOL(snd_pcm_set_ops);
 480
 481/**
 482 * snd_pcm_sync - set the PCM sync id
 483 * @substream: the pcm substream
 484 *
 485 * Sets the PCM sync identifier for the card.
 486 */
 487void snd_pcm_set_sync(struct snd_pcm_substream *substream)
 488{
 489        struct snd_pcm_runtime *runtime = substream->runtime;
 490        
 491        runtime->sync.id32[0] = substream->pcm->card->number;
 492        runtime->sync.id32[1] = -1;
 493        runtime->sync.id32[2] = -1;
 494        runtime->sync.id32[3] = -1;
 495}
 496EXPORT_SYMBOL(snd_pcm_set_sync);
 497
 498/*
 499 *  Standard ioctl routine
 500 */
 501
 502static inline unsigned int div32(unsigned int a, unsigned int b, 
 503                                 unsigned int *r)
 504{
 505        if (b == 0) {
 506                *r = 0;
 507                return UINT_MAX;
 508        }
 509        *r = a % b;
 510        return a / b;
 511}
 512
 513static inline unsigned int div_down(unsigned int a, unsigned int b)
 514{
 515        if (b == 0)
 516                return UINT_MAX;
 517        return a / b;
 518}
 519
 520static inline unsigned int div_up(unsigned int a, unsigned int b)
 521{
 522        unsigned int r;
 523        unsigned int q;
 524        if (b == 0)
 525                return UINT_MAX;
 526        q = div32(a, b, &r);
 527        if (r)
 528                ++q;
 529        return q;
 530}
 531
 532static inline unsigned int mul(unsigned int a, unsigned int b)
 533{
 534        if (a == 0)
 535                return 0;
 536        if (div_down(UINT_MAX, a) < b)
 537                return UINT_MAX;
 538        return a * b;
 539}
 540
 541static inline unsigned int muldiv32(unsigned int a, unsigned int b,
 542                                    unsigned int c, unsigned int *r)
 543{
 544        u_int64_t n = (u_int64_t) a * b;
 545        if (c == 0) {
 546                *r = 0;
 547                return UINT_MAX;
 548        }
 549        n = div_u64_rem(n, c, r);
 550        if (n >= UINT_MAX) {
 551                *r = 0;
 552                return UINT_MAX;
 553        }
 554        return n;
 555}
 556
 557/**
 558 * snd_interval_refine - refine the interval value of configurator
 559 * @i: the interval value to refine
 560 * @v: the interval value to refer to
 561 *
 562 * Refines the interval value with the reference value.
 563 * The interval is changed to the range satisfying both intervals.
 564 * The interval status (min, max, integer, etc.) are evaluated.
 565 *
 566 * Return: Positive if the value is changed, zero if it's not changed, or a
 567 * negative error code.
 568 */
 569int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
 570{
 571        int changed = 0;
 572        if (snd_BUG_ON(snd_interval_empty(i)))
 573                return -EINVAL;
 574        if (i->min < v->min) {
 575                i->min = v->min;
 576                i->openmin = v->openmin;
 577                changed = 1;
 578        } else if (i->min == v->min && !i->openmin && v->openmin) {
 579                i->openmin = 1;
 580                changed = 1;
 581        }
 582        if (i->max > v->max) {
 583                i->max = v->max;
 584                i->openmax = v->openmax;
 585                changed = 1;
 586        } else if (i->max == v->max && !i->openmax && v->openmax) {
 587                i->openmax = 1;
 588                changed = 1;
 589        }
 590        if (!i->integer && v->integer) {
 591                i->integer = 1;
 592                changed = 1;
 593        }
 594        if (i->integer) {
 595                if (i->openmin) {
 596                        i->min++;
 597                        i->openmin = 0;
 598                }
 599                if (i->openmax) {
 600                        i->max--;
 601                        i->openmax = 0;
 602                }
 603        } else if (!i->openmin && !i->openmax && i->min == i->max)
 604                i->integer = 1;
 605        if (snd_interval_checkempty(i)) {
 606                snd_interval_none(i);
 607                return -EINVAL;
 608        }
 609        return changed;
 610}
 611EXPORT_SYMBOL(snd_interval_refine);
 612
 613static int snd_interval_refine_first(struct snd_interval *i)
 614{
 615        const unsigned int last_max = i->max;
 616
 617        if (snd_BUG_ON(snd_interval_empty(i)))
 618                return -EINVAL;
 619        if (snd_interval_single(i))
 620                return 0;
 621        i->max = i->min;
 622        if (i->openmin)
 623                i->max++;
 624        /* only exclude max value if also excluded before refine */
 625        i->openmax = (i->openmax && i->max >= last_max);
 626        return 1;
 627}
 628
 629static int snd_interval_refine_last(struct snd_interval *i)
 630{
 631        const unsigned int last_min = i->min;
 632
 633        if (snd_BUG_ON(snd_interval_empty(i)))
 634                return -EINVAL;
 635        if (snd_interval_single(i))
 636                return 0;
 637        i->min = i->max;
 638        if (i->openmax)
 639                i->min--;
 640        /* only exclude min value if also excluded before refine */
 641        i->openmin = (i->openmin && i->min <= last_min);
 642        return 1;
 643}
 644
 645void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 646{
 647        if (a->empty || b->empty) {
 648                snd_interval_none(c);
 649                return;
 650        }
 651        c->empty = 0;
 652        c->min = mul(a->min, b->min);
 653        c->openmin = (a->openmin || b->openmin);
 654        c->max = mul(a->max,  b->max);
 655        c->openmax = (a->openmax || b->openmax);
 656        c->integer = (a->integer && b->integer);
 657}
 658
 659/**
 660 * snd_interval_div - refine the interval value with division
 661 * @a: dividend
 662 * @b: divisor
 663 * @c: quotient
 664 *
 665 * c = a / b
 666 *
 667 * Returns non-zero if the value is changed, zero if not changed.
 668 */
 669void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 670{
 671        unsigned int r;
 672        if (a->empty || b->empty) {
 673                snd_interval_none(c);
 674                return;
 675        }
 676        c->empty = 0;
 677        c->min = div32(a->min, b->max, &r);
 678        c->openmin = (r || a->openmin || b->openmax);
 679        if (b->min > 0) {
 680                c->max = div32(a->max, b->min, &r);
 681                if (r) {
 682                        c->max++;
 683                        c->openmax = 1;
 684                } else
 685                        c->openmax = (a->openmax || b->openmin);
 686        } else {
 687                c->max = UINT_MAX;
 688                c->openmax = 0;
 689        }
 690        c->integer = 0;
 691}
 692
 693/**
 694 * snd_interval_muldivk - refine the interval value
 695 * @a: dividend 1
 696 * @b: dividend 2
 697 * @k: divisor (as integer)
 698 * @c: result
 699  *
 700 * c = a * b / k
 701 *
 702 * Returns non-zero if the value is changed, zero if not changed.
 703 */
 704void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
 705                      unsigned int k, struct snd_interval *c)
 706{
 707        unsigned int r;
 708        if (a->empty || b->empty) {
 709                snd_interval_none(c);
 710                return;
 711        }
 712        c->empty = 0;
 713        c->min = muldiv32(a->min, b->min, k, &r);
 714        c->openmin = (r || a->openmin || b->openmin);
 715        c->max = muldiv32(a->max, b->max, k, &r);
 716        if (r) {
 717                c->max++;
 718                c->openmax = 1;
 719        } else
 720                c->openmax = (a->openmax || b->openmax);
 721        c->integer = 0;
 722}
 723
 724/**
 725 * snd_interval_mulkdiv - refine the interval value
 726 * @a: dividend 1
 727 * @k: dividend 2 (as integer)
 728 * @b: divisor
 729 * @c: result
 730 *
 731 * c = a * k / b
 732 *
 733 * Returns non-zero if the value is changed, zero if not changed.
 734 */
 735void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
 736                      const struct snd_interval *b, struct snd_interval *c)
 737{
 738        unsigned int r;
 739        if (a->empty || b->empty) {
 740                snd_interval_none(c);
 741                return;
 742        }
 743        c->empty = 0;
 744        c->min = muldiv32(a->min, k, b->max, &r);
 745        c->openmin = (r || a->openmin || b->openmax);
 746        if (b->min > 0) {
 747                c->max = muldiv32(a->max, k, b->min, &r);
 748                if (r) {
 749                        c->max++;
 750                        c->openmax = 1;
 751                } else
 752                        c->openmax = (a->openmax || b->openmin);
 753        } else {
 754                c->max = UINT_MAX;
 755                c->openmax = 0;
 756        }
 757        c->integer = 0;
 758}
 759
 760/* ---- */
 761
 762
 763/**
 764 * snd_interval_ratnum - refine the interval value
 765 * @i: interval to refine
 766 * @rats_count: number of ratnum_t 
 767 * @rats: ratnum_t array
 768 * @nump: pointer to store the resultant numerator
 769 * @denp: pointer to store the resultant denominator
 770 *
 771 * Return: Positive if the value is changed, zero if it's not changed, or a
 772 * negative error code.
 773 */
 774int snd_interval_ratnum(struct snd_interval *i,
 775                        unsigned int rats_count, const struct snd_ratnum *rats,
 776                        unsigned int *nump, unsigned int *denp)
 777{
 778        unsigned int best_num, best_den;
 779        int best_diff;
 780        unsigned int k;
 781        struct snd_interval t;
 782        int err;
 783        unsigned int result_num, result_den;
 784        int result_diff;
 785
 786        best_num = best_den = best_diff = 0;
 787        for (k = 0; k < rats_count; ++k) {
 788                unsigned int num = rats[k].num;
 789                unsigned int den;
 790                unsigned int q = i->min;
 791                int diff;
 792                if (q == 0)
 793                        q = 1;
 794                den = div_up(num, q);
 795                if (den < rats[k].den_min)
 796                        continue;
 797                if (den > rats[k].den_max)
 798                        den = rats[k].den_max;
 799                else {
 800                        unsigned int r;
 801                        r = (den - rats[k].den_min) % rats[k].den_step;
 802                        if (r != 0)
 803                                den -= r;
 804                }
 805                diff = num - q * den;
 806                if (diff < 0)
 807                        diff = -diff;
 808                if (best_num == 0 ||
 809                    diff * best_den < best_diff * den) {
 810                        best_diff = diff;
 811                        best_den = den;
 812                        best_num = num;
 813                }
 814        }
 815        if (best_den == 0) {
 816                i->empty = 1;
 817                return -EINVAL;
 818        }
 819        t.min = div_down(best_num, best_den);
 820        t.openmin = !!(best_num % best_den);
 821        
 822        result_num = best_num;
 823        result_diff = best_diff;
 824        result_den = best_den;
 825        best_num = best_den = best_diff = 0;
 826        for (k = 0; k < rats_count; ++k) {
 827                unsigned int num = rats[k].num;
 828                unsigned int den;
 829                unsigned int q = i->max;
 830                int diff;
 831                if (q == 0) {
 832                        i->empty = 1;
 833                        return -EINVAL;
 834                }
 835                den = div_down(num, q);
 836                if (den > rats[k].den_max)
 837                        continue;
 838                if (den < rats[k].den_min)
 839                        den = rats[k].den_min;
 840                else {
 841                        unsigned int r;
 842                        r = (den - rats[k].den_min) % rats[k].den_step;
 843                        if (r != 0)
 844                                den += rats[k].den_step - r;
 845                }
 846                diff = q * den - num;
 847                if (diff < 0)
 848                        diff = -diff;
 849                if (best_num == 0 ||
 850                    diff * best_den < best_diff * den) {
 851                        best_diff = diff;
 852                        best_den = den;
 853                        best_num = num;
 854                }
 855        }
 856        if (best_den == 0) {
 857                i->empty = 1;
 858                return -EINVAL;
 859        }
 860        t.max = div_up(best_num, best_den);
 861        t.openmax = !!(best_num % best_den);
 862        t.integer = 0;
 863        err = snd_interval_refine(i, &t);
 864        if (err < 0)
 865                return err;
 866
 867        if (snd_interval_single(i)) {
 868                if (best_diff * result_den < result_diff * best_den) {
 869                        result_num = best_num;
 870                        result_den = best_den;
 871                }
 872                if (nump)
 873                        *nump = result_num;
 874                if (denp)
 875                        *denp = result_den;
 876        }
 877        return err;
 878}
 879EXPORT_SYMBOL(snd_interval_ratnum);
 880
 881/**
 882 * snd_interval_ratden - refine the interval value
 883 * @i: interval to refine
 884 * @rats_count: number of struct ratden
 885 * @rats: struct ratden array
 886 * @nump: pointer to store the resultant numerator
 887 * @denp: pointer to store the resultant denominator
 888 *
 889 * Return: Positive if the value is changed, zero if it's not changed, or a
 890 * negative error code.
 891 */
 892static int snd_interval_ratden(struct snd_interval *i,
 893                               unsigned int rats_count,
 894                               const struct snd_ratden *rats,
 895                               unsigned int *nump, unsigned int *denp)
 896{
 897        unsigned int best_num, best_diff, best_den;
 898        unsigned int k;
 899        struct snd_interval t;
 900        int err;
 901
 902        best_num = best_den = best_diff = 0;
 903        for (k = 0; k < rats_count; ++k) {
 904                unsigned int num;
 905                unsigned int den = rats[k].den;
 906                unsigned int q = i->min;
 907                int diff;
 908                num = mul(q, den);
 909                if (num > rats[k].num_max)
 910                        continue;
 911                if (num < rats[k].num_min)
 912                        num = rats[k].num_max;
 913                else {
 914                        unsigned int r;
 915                        r = (num - rats[k].num_min) % rats[k].num_step;
 916                        if (r != 0)
 917                                num += rats[k].num_step - r;
 918                }
 919                diff = num - q * den;
 920                if (best_num == 0 ||
 921                    diff * best_den < best_diff * den) {
 922                        best_diff = diff;
 923                        best_den = den;
 924                        best_num = num;
 925                }
 926        }
 927        if (best_den == 0) {
 928                i->empty = 1;
 929                return -EINVAL;
 930        }
 931        t.min = div_down(best_num, best_den);
 932        t.openmin = !!(best_num % best_den);
 933        
 934        best_num = best_den = best_diff = 0;
 935        for (k = 0; k < rats_count; ++k) {
 936                unsigned int num;
 937                unsigned int den = rats[k].den;
 938                unsigned int q = i->max;
 939                int diff;
 940                num = mul(q, den);
 941                if (num < rats[k].num_min)
 942                        continue;
 943                if (num > rats[k].num_max)
 944                        num = rats[k].num_max;
 945                else {
 946                        unsigned int r;
 947                        r = (num - rats[k].num_min) % rats[k].num_step;
 948                        if (r != 0)
 949                                num -= r;
 950                }
 951                diff = q * den - num;
 952                if (best_num == 0 ||
 953                    diff * best_den < best_diff * den) {
 954                        best_diff = diff;
 955                        best_den = den;
 956                        best_num = num;
 957                }
 958        }
 959        if (best_den == 0) {
 960                i->empty = 1;
 961                return -EINVAL;
 962        }
 963        t.max = div_up(best_num, best_den);
 964        t.openmax = !!(best_num % best_den);
 965        t.integer = 0;
 966        err = snd_interval_refine(i, &t);
 967        if (err < 0)
 968                return err;
 969
 970        if (snd_interval_single(i)) {
 971                if (nump)
 972                        *nump = best_num;
 973                if (denp)
 974                        *denp = best_den;
 975        }
 976        return err;
 977}
 978
 979/**
 980 * snd_interval_list - refine the interval value from the list
 981 * @i: the interval value to refine
 982 * @count: the number of elements in the list
 983 * @list: the value list
 984 * @mask: the bit-mask to evaluate
 985 *
 986 * Refines the interval value from the list.
 987 * When mask is non-zero, only the elements corresponding to bit 1 are
 988 * evaluated.
 989 *
 990 * Return: Positive if the value is changed, zero if it's not changed, or a
 991 * negative error code.
 992 */
 993int snd_interval_list(struct snd_interval *i, unsigned int count,
 994                      const unsigned int *list, unsigned int mask)
 995{
 996        unsigned int k;
 997        struct snd_interval list_range;
 998
 999        if (!count) {
1000                i->empty = 1;
1001                return -EINVAL;
1002        }
1003        snd_interval_any(&list_range);
1004        list_range.min = UINT_MAX;
1005        list_range.max = 0;
1006        for (k = 0; k < count; k++) {
1007                if (mask && !(mask & (1 << k)))
1008                        continue;
1009                if (!snd_interval_test(i, list[k]))
1010                        continue;
1011                list_range.min = min(list_range.min, list[k]);
1012                list_range.max = max(list_range.max, list[k]);
1013        }
1014        return snd_interval_refine(i, &list_range);
1015}
1016EXPORT_SYMBOL(snd_interval_list);
1017
1018/**
1019 * snd_interval_ranges - refine the interval value from the list of ranges
1020 * @i: the interval value to refine
1021 * @count: the number of elements in the list of ranges
1022 * @ranges: the ranges list
1023 * @mask: the bit-mask to evaluate
1024 *
1025 * Refines the interval value from the list of ranges.
1026 * When mask is non-zero, only the elements corresponding to bit 1 are
1027 * evaluated.
1028 *
1029 * Return: Positive if the value is changed, zero if it's not changed, or a
1030 * negative error code.
1031 */
1032int snd_interval_ranges(struct snd_interval *i, unsigned int count,
1033                        const struct snd_interval *ranges, unsigned int mask)
1034{
1035        unsigned int k;
1036        struct snd_interval range_union;
1037        struct snd_interval range;
1038
1039        if (!count) {
1040                snd_interval_none(i);
1041                return -EINVAL;
1042        }
1043        snd_interval_any(&range_union);
1044        range_union.min = UINT_MAX;
1045        range_union.max = 0;
1046        for (k = 0; k < count; k++) {
1047                if (mask && !(mask & (1 << k)))
1048                        continue;
1049                snd_interval_copy(&range, &ranges[k]);
1050                if (snd_interval_refine(&range, i) < 0)
1051                        continue;
1052                if (snd_interval_empty(&range))
1053                        continue;
1054
1055                if (range.min < range_union.min) {
1056                        range_union.min = range.min;
1057                        range_union.openmin = 1;
1058                }
1059                if (range.min == range_union.min && !range.openmin)
1060                        range_union.openmin = 0;
1061                if (range.max > range_union.max) {
1062                        range_union.max = range.max;
1063                        range_union.openmax = 1;
1064                }
1065                if (range.max == range_union.max && !range.openmax)
1066                        range_union.openmax = 0;
1067        }
1068        return snd_interval_refine(i, &range_union);
1069}
1070EXPORT_SYMBOL(snd_interval_ranges);
1071
1072static int snd_interval_step(struct snd_interval *i, unsigned int step)
1073{
1074        unsigned int n;
1075        int changed = 0;
1076        n = i->min % step;
1077        if (n != 0 || i->openmin) {
1078                i->min += step - n;
1079                i->openmin = 0;
1080                changed = 1;
1081        }
1082        n = i->max % step;
1083        if (n != 0 || i->openmax) {
1084                i->max -= n;
1085                i->openmax = 0;
1086                changed = 1;
1087        }
1088        if (snd_interval_checkempty(i)) {
1089                i->empty = 1;
1090                return -EINVAL;
1091        }
1092        return changed;
1093}
1094
1095/* Info constraints helpers */
1096
1097/**
1098 * snd_pcm_hw_rule_add - add the hw-constraint rule
1099 * @runtime: the pcm runtime instance
1100 * @cond: condition bits
1101 * @var: the variable to evaluate
1102 * @func: the evaluation function
1103 * @private: the private data pointer passed to function
1104 * @dep: the dependent variables
1105 *
1106 * Return: Zero if successful, or a negative error code on failure.
1107 */
1108int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1109                        int var,
1110                        snd_pcm_hw_rule_func_t func, void *private,
1111                        int dep, ...)
1112{
1113        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1114        struct snd_pcm_hw_rule *c;
1115        unsigned int k;
1116        va_list args;
1117        va_start(args, dep);
1118        if (constrs->rules_num >= constrs->rules_all) {
1119                struct snd_pcm_hw_rule *new;
1120                unsigned int new_rules = constrs->rules_all + 16;
1121                new = krealloc(constrs->rules, new_rules * sizeof(*c),
1122                               GFP_KERNEL);
1123                if (!new) {
1124                        va_end(args);
1125                        return -ENOMEM;
1126                }
1127                constrs->rules = new;
1128                constrs->rules_all = new_rules;
1129        }
1130        c = &constrs->rules[constrs->rules_num];
1131        c->cond = cond;
1132        c->func = func;
1133        c->var = var;
1134        c->private = private;
1135        k = 0;
1136        while (1) {
1137                if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1138                        va_end(args);
1139                        return -EINVAL;
1140                }
1141                c->deps[k++] = dep;
1142                if (dep < 0)
1143                        break;
1144                dep = va_arg(args, int);
1145        }
1146        constrs->rules_num++;
1147        va_end(args);
1148        return 0;
1149}
1150EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1151
1152/**
1153 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1154 * @runtime: PCM runtime instance
1155 * @var: hw_params variable to apply the mask
1156 * @mask: the bitmap mask
1157 *
1158 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1159 *
1160 * Return: Zero if successful, or a negative error code on failure.
1161 */
1162int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1163                               u_int32_t mask)
1164{
1165        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1166        struct snd_mask *maskp = constrs_mask(constrs, var);
1167        *maskp->bits &= mask;
1168        memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1169        if (*maskp->bits == 0)
1170                return -EINVAL;
1171        return 0;
1172}
1173
1174/**
1175 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1176 * @runtime: PCM runtime instance
1177 * @var: hw_params variable to apply the mask
1178 * @mask: the 64bit bitmap mask
1179 *
1180 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1181 *
1182 * Return: Zero if successful, or a negative error code on failure.
1183 */
1184int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1185                                 u_int64_t mask)
1186{
1187        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1188        struct snd_mask *maskp = constrs_mask(constrs, var);
1189        maskp->bits[0] &= (u_int32_t)mask;
1190        maskp->bits[1] &= (u_int32_t)(mask >> 32);
1191        memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1192        if (! maskp->bits[0] && ! maskp->bits[1])
1193                return -EINVAL;
1194        return 0;
1195}
1196EXPORT_SYMBOL(snd_pcm_hw_constraint_mask64);
1197
1198/**
1199 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1200 * @runtime: PCM runtime instance
1201 * @var: hw_params variable to apply the integer constraint
1202 *
1203 * Apply the constraint of integer to an interval parameter.
1204 *
1205 * Return: Positive if the value is changed, zero if it's not changed, or a
1206 * negative error code.
1207 */
1208int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1209{
1210        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1211        return snd_interval_setinteger(constrs_interval(constrs, var));
1212}
1213EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1214
1215/**
1216 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1217 * @runtime: PCM runtime instance
1218 * @var: hw_params variable to apply the range
1219 * @min: the minimal value
1220 * @max: the maximal value
1221 * 
1222 * Apply the min/max range constraint to an interval parameter.
1223 *
1224 * Return: Positive if the value is changed, zero if it's not changed, or a
1225 * negative error code.
1226 */
1227int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1228                                 unsigned int min, unsigned int max)
1229{
1230        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1231        struct snd_interval t;
1232        t.min = min;
1233        t.max = max;
1234        t.openmin = t.openmax = 0;
1235        t.integer = 0;
1236        return snd_interval_refine(constrs_interval(constrs, var), &t);
1237}
1238EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1239
1240static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1241                                struct snd_pcm_hw_rule *rule)
1242{
1243        struct snd_pcm_hw_constraint_list *list = rule->private;
1244        return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1245}               
1246
1247
1248/**
1249 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1250 * @runtime: PCM runtime instance
1251 * @cond: condition bits
1252 * @var: hw_params variable to apply the list constraint
1253 * @l: list
1254 * 
1255 * Apply the list of constraints to an interval parameter.
1256 *
1257 * Return: Zero if successful, or a negative error code on failure.
1258 */
1259int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1260                               unsigned int cond,
1261                               snd_pcm_hw_param_t var,
1262                               const struct snd_pcm_hw_constraint_list *l)
1263{
1264        return snd_pcm_hw_rule_add(runtime, cond, var,
1265                                   snd_pcm_hw_rule_list, (void *)l,
1266                                   var, -1);
1267}
1268EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1269
1270static int snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params *params,
1271                                  struct snd_pcm_hw_rule *rule)
1272{
1273        struct snd_pcm_hw_constraint_ranges *r = rule->private;
1274        return snd_interval_ranges(hw_param_interval(params, rule->var),
1275                                   r->count, r->ranges, r->mask);
1276}
1277
1278
1279/**
1280 * snd_pcm_hw_constraint_ranges - apply list of range constraints to a parameter
1281 * @runtime: PCM runtime instance
1282 * @cond: condition bits
1283 * @var: hw_params variable to apply the list of range constraints
1284 * @r: ranges
1285 *
1286 * Apply the list of range constraints to an interval parameter.
1287 *
1288 * Return: Zero if successful, or a negative error code on failure.
1289 */
1290int snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime *runtime,
1291                                 unsigned int cond,
1292                                 snd_pcm_hw_param_t var,
1293                                 const struct snd_pcm_hw_constraint_ranges *r)
1294{
1295        return snd_pcm_hw_rule_add(runtime, cond, var,
1296                                   snd_pcm_hw_rule_ranges, (void *)r,
1297                                   var, -1);
1298}
1299EXPORT_SYMBOL(snd_pcm_hw_constraint_ranges);
1300
1301static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1302                                   struct snd_pcm_hw_rule *rule)
1303{
1304        const struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1305        unsigned int num = 0, den = 0;
1306        int err;
1307        err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1308                                  r->nrats, r->rats, &num, &den);
1309        if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1310                params->rate_num = num;
1311                params->rate_den = den;
1312        }
1313        return err;
1314}
1315
1316/**
1317 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1318 * @runtime: PCM runtime instance
1319 * @cond: condition bits
1320 * @var: hw_params variable to apply the ratnums constraint
1321 * @r: struct snd_ratnums constriants
1322 *
1323 * Return: Zero if successful, or a negative error code on failure.
1324 */
1325int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime, 
1326                                  unsigned int cond,
1327                                  snd_pcm_hw_param_t var,
1328                                  const struct snd_pcm_hw_constraint_ratnums *r)
1329{
1330        return snd_pcm_hw_rule_add(runtime, cond, var,
1331                                   snd_pcm_hw_rule_ratnums, (void *)r,
1332                                   var, -1);
1333}
1334EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1335
1336static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1337                                   struct snd_pcm_hw_rule *rule)
1338{
1339        const struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1340        unsigned int num = 0, den = 0;
1341        int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1342                                  r->nrats, r->rats, &num, &den);
1343        if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1344                params->rate_num = num;
1345                params->rate_den = den;
1346        }
1347        return err;
1348}
1349
1350/**
1351 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1352 * @runtime: PCM runtime instance
1353 * @cond: condition bits
1354 * @var: hw_params variable to apply the ratdens constraint
1355 * @r: struct snd_ratdens constriants
1356 *
1357 * Return: Zero if successful, or a negative error code on failure.
1358 */
1359int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime, 
1360                                  unsigned int cond,
1361                                  snd_pcm_hw_param_t var,
1362                                  const struct snd_pcm_hw_constraint_ratdens *r)
1363{
1364        return snd_pcm_hw_rule_add(runtime, cond, var,
1365                                   snd_pcm_hw_rule_ratdens, (void *)r,
1366                                   var, -1);
1367}
1368EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1369
1370static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1371                                  struct snd_pcm_hw_rule *rule)
1372{
1373        unsigned int l = (unsigned long) rule->private;
1374        int width = l & 0xffff;
1375        unsigned int msbits = l >> 16;
1376        const struct snd_interval *i =
1377                hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1378
1379        if (!snd_interval_single(i))
1380                return 0;
1381
1382        if ((snd_interval_value(i) == width) ||
1383            (width == 0 && snd_interval_value(i) > msbits))
1384                params->msbits = min_not_zero(params->msbits, msbits);
1385
1386        return 0;
1387}
1388
1389/**
1390 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1391 * @runtime: PCM runtime instance
1392 * @cond: condition bits
1393 * @width: sample bits width
1394 * @msbits: msbits width
1395 *
1396 * This constraint will set the number of most significant bits (msbits) if a
1397 * sample format with the specified width has been select. If width is set to 0
1398 * the msbits will be set for any sample format with a width larger than the
1399 * specified msbits.
1400 *
1401 * Return: Zero if successful, or a negative error code on failure.
1402 */
1403int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime, 
1404                                 unsigned int cond,
1405                                 unsigned int width,
1406                                 unsigned int msbits)
1407{
1408        unsigned long l = (msbits << 16) | width;
1409        return snd_pcm_hw_rule_add(runtime, cond, -1,
1410                                    snd_pcm_hw_rule_msbits,
1411                                    (void*) l,
1412                                    SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1413}
1414EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1415
1416static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1417                                struct snd_pcm_hw_rule *rule)
1418{
1419        unsigned long step = (unsigned long) rule->private;
1420        return snd_interval_step(hw_param_interval(params, rule->var), step);
1421}
1422
1423/**
1424 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1425 * @runtime: PCM runtime instance
1426 * @cond: condition bits
1427 * @var: hw_params variable to apply the step constraint
1428 * @step: step size
1429 *
1430 * Return: Zero if successful, or a negative error code on failure.
1431 */
1432int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1433                               unsigned int cond,
1434                               snd_pcm_hw_param_t var,
1435                               unsigned long step)
1436{
1437        return snd_pcm_hw_rule_add(runtime, cond, var, 
1438                                   snd_pcm_hw_rule_step, (void *) step,
1439                                   var, -1);
1440}
1441EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1442
1443static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1444{
1445        static unsigned int pow2_sizes[] = {
1446                1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1447                1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1448                1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1449                1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1450        };
1451        return snd_interval_list(hw_param_interval(params, rule->var),
1452                                 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1453}               
1454
1455/**
1456 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1457 * @runtime: PCM runtime instance
1458 * @cond: condition bits
1459 * @var: hw_params variable to apply the power-of-2 constraint
1460 *
1461 * Return: Zero if successful, or a negative error code on failure.
1462 */
1463int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1464                               unsigned int cond,
1465                               snd_pcm_hw_param_t var)
1466{
1467        return snd_pcm_hw_rule_add(runtime, cond, var, 
1468                                   snd_pcm_hw_rule_pow2, NULL,
1469                                   var, -1);
1470}
1471EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1472
1473static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1474                                           struct snd_pcm_hw_rule *rule)
1475{
1476        unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1477        struct snd_interval *rate;
1478
1479        rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1480        return snd_interval_list(rate, 1, &base_rate, 0);
1481}
1482
1483/**
1484 * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1485 * @runtime: PCM runtime instance
1486 * @base_rate: the rate at which the hardware does not resample
1487 *
1488 * Return: Zero if successful, or a negative error code on failure.
1489 */
1490int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1491                               unsigned int base_rate)
1492{
1493        return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1494                                   SNDRV_PCM_HW_PARAM_RATE,
1495                                   snd_pcm_hw_rule_noresample_func,
1496                                   (void *)(uintptr_t)base_rate,
1497                                   SNDRV_PCM_HW_PARAM_RATE, -1);
1498}
1499EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1500
1501static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1502                                  snd_pcm_hw_param_t var)
1503{
1504        if (hw_is_mask(var)) {
1505                snd_mask_any(hw_param_mask(params, var));
1506                params->cmask |= 1 << var;
1507                params->rmask |= 1 << var;
1508                return;
1509        }
1510        if (hw_is_interval(var)) {
1511                snd_interval_any(hw_param_interval(params, var));
1512                params->cmask |= 1 << var;
1513                params->rmask |= 1 << var;
1514                return;
1515        }
1516        snd_BUG();
1517}
1518
1519void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1520{
1521        unsigned int k;
1522        memset(params, 0, sizeof(*params));
1523        for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1524                _snd_pcm_hw_param_any(params, k);
1525        for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1526                _snd_pcm_hw_param_any(params, k);
1527        params->info = ~0U;
1528}
1529EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1530
1531/**
1532 * snd_pcm_hw_param_value - return @params field @var value
1533 * @params: the hw_params instance
1534 * @var: parameter to retrieve
1535 * @dir: pointer to the direction (-1,0,1) or %NULL
1536 *
1537 * Return: The value for field @var if it's fixed in configuration space
1538 * defined by @params. -%EINVAL otherwise.
1539 */
1540int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1541                           snd_pcm_hw_param_t var, int *dir)
1542{
1543        if (hw_is_mask(var)) {
1544                const struct snd_mask *mask = hw_param_mask_c(params, var);
1545                if (!snd_mask_single(mask))
1546                        return -EINVAL;
1547                if (dir)
1548                        *dir = 0;
1549                return snd_mask_value(mask);
1550        }
1551        if (hw_is_interval(var)) {
1552                const struct snd_interval *i = hw_param_interval_c(params, var);
1553                if (!snd_interval_single(i))
1554                        return -EINVAL;
1555                if (dir)
1556                        *dir = i->openmin;
1557                return snd_interval_value(i);
1558        }
1559        return -EINVAL;
1560}
1561EXPORT_SYMBOL(snd_pcm_hw_param_value);
1562
1563void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1564                                snd_pcm_hw_param_t var)
1565{
1566        if (hw_is_mask(var)) {
1567                snd_mask_none(hw_param_mask(params, var));
1568                params->cmask |= 1 << var;
1569                params->rmask |= 1 << var;
1570        } else if (hw_is_interval(var)) {
1571                snd_interval_none(hw_param_interval(params, var));
1572                params->cmask |= 1 << var;
1573                params->rmask |= 1 << var;
1574        } else {
1575                snd_BUG();
1576        }
1577}
1578EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1579
1580static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1581                                   snd_pcm_hw_param_t var)
1582{
1583        int changed;
1584        if (hw_is_mask(var))
1585                changed = snd_mask_refine_first(hw_param_mask(params, var));
1586        else if (hw_is_interval(var))
1587                changed = snd_interval_refine_first(hw_param_interval(params, var));
1588        else
1589                return -EINVAL;
1590        if (changed > 0) {
1591                params->cmask |= 1 << var;
1592                params->rmask |= 1 << var;
1593        }
1594        return changed;
1595}
1596
1597
1598/**
1599 * snd_pcm_hw_param_first - refine config space and return minimum value
1600 * @pcm: PCM instance
1601 * @params: the hw_params instance
1602 * @var: parameter to retrieve
1603 * @dir: pointer to the direction (-1,0,1) or %NULL
1604 *
1605 * Inside configuration space defined by @params remove from @var all
1606 * values > minimum. Reduce configuration space accordingly.
1607 *
1608 * Return: The minimum, or a negative error code on failure.
1609 */
1610int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm, 
1611                           struct snd_pcm_hw_params *params, 
1612                           snd_pcm_hw_param_t var, int *dir)
1613{
1614        int changed = _snd_pcm_hw_param_first(params, var);
1615        if (changed < 0)
1616                return changed;
1617        if (params->rmask) {
1618                int err = snd_pcm_hw_refine(pcm, params);
1619                if (err < 0)
1620                        return err;
1621        }
1622        return snd_pcm_hw_param_value(params, var, dir);
1623}
1624EXPORT_SYMBOL(snd_pcm_hw_param_first);
1625
1626static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1627                                  snd_pcm_hw_param_t var)
1628{
1629        int changed;
1630        if (hw_is_mask(var))
1631                changed = snd_mask_refine_last(hw_param_mask(params, var));
1632        else if (hw_is_interval(var))
1633                changed = snd_interval_refine_last(hw_param_interval(params, var));
1634        else
1635                return -EINVAL;
1636        if (changed > 0) {
1637                params->cmask |= 1 << var;
1638                params->rmask |= 1 << var;
1639        }
1640        return changed;
1641}
1642
1643
1644/**
1645 * snd_pcm_hw_param_last - refine config space and return maximum value
1646 * @pcm: PCM instance
1647 * @params: the hw_params instance
1648 * @var: parameter to retrieve
1649 * @dir: pointer to the direction (-1,0,1) or %NULL
1650 *
1651 * Inside configuration space defined by @params remove from @var all
1652 * values < maximum. Reduce configuration space accordingly.
1653 *
1654 * Return: The maximum, or a negative error code on failure.
1655 */
1656int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm, 
1657                          struct snd_pcm_hw_params *params,
1658                          snd_pcm_hw_param_t var, int *dir)
1659{
1660        int changed = _snd_pcm_hw_param_last(params, var);
1661        if (changed < 0)
1662                return changed;
1663        if (params->rmask) {
1664                int err = snd_pcm_hw_refine(pcm, params);
1665                if (err < 0)
1666                        return err;
1667        }
1668        return snd_pcm_hw_param_value(params, var, dir);
1669}
1670EXPORT_SYMBOL(snd_pcm_hw_param_last);
1671
1672static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1673                                   void *arg)
1674{
1675        struct snd_pcm_runtime *runtime = substream->runtime;
1676        unsigned long flags;
1677        snd_pcm_stream_lock_irqsave(substream, flags);
1678        if (snd_pcm_running(substream) &&
1679            snd_pcm_update_hw_ptr(substream) >= 0)
1680                runtime->status->hw_ptr %= runtime->buffer_size;
1681        else {
1682                runtime->status->hw_ptr = 0;
1683                runtime->hw_ptr_wrap = 0;
1684        }
1685        snd_pcm_stream_unlock_irqrestore(substream, flags);
1686        return 0;
1687}
1688
1689static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1690                                          void *arg)
1691{
1692        struct snd_pcm_channel_info *info = arg;
1693        struct snd_pcm_runtime *runtime = substream->runtime;
1694        int width;
1695        if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1696                info->offset = -1;
1697                return 0;
1698        }
1699        width = snd_pcm_format_physical_width(runtime->format);
1700        if (width < 0)
1701                return width;
1702        info->offset = 0;
1703        switch (runtime->access) {
1704        case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1705        case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1706                info->first = info->channel * width;
1707                info->step = runtime->channels * width;
1708                break;
1709        case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1710        case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1711        {
1712                size_t size = runtime->dma_bytes / runtime->channels;
1713                info->first = info->channel * size * 8;
1714                info->step = width;
1715                break;
1716        }
1717        default:
1718                snd_BUG();
1719                break;
1720        }
1721        return 0;
1722}
1723
1724static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1725                                       void *arg)
1726{
1727        struct snd_pcm_hw_params *params = arg;
1728        snd_pcm_format_t format;
1729        int channels;
1730        ssize_t frame_size;
1731
1732        params->fifo_size = substream->runtime->hw.fifo_size;
1733        if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1734                format = params_format(params);
1735                channels = params_channels(params);
1736                frame_size = snd_pcm_format_size(format, channels);
1737                if (frame_size > 0)
1738                        params->fifo_size /= (unsigned)frame_size;
1739        }
1740        return 0;
1741}
1742
1743/**
1744 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1745 * @substream: the pcm substream instance
1746 * @cmd: ioctl command
1747 * @arg: ioctl argument
1748 *
1749 * Processes the generic ioctl commands for PCM.
1750 * Can be passed as the ioctl callback for PCM ops.
1751 *
1752 * Return: Zero if successful, or a negative error code on failure.
1753 */
1754int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1755                      unsigned int cmd, void *arg)
1756{
1757        switch (cmd) {
1758        case SNDRV_PCM_IOCTL1_RESET:
1759                return snd_pcm_lib_ioctl_reset(substream, arg);
1760        case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1761                return snd_pcm_lib_ioctl_channel_info(substream, arg);
1762        case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1763                return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1764        }
1765        return -ENXIO;
1766}
1767EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1768
1769/**
1770 * snd_pcm_period_elapsed - update the pcm status for the next period
1771 * @substream: the pcm substream instance
1772 *
1773 * This function is called from the interrupt handler when the
1774 * PCM has processed the period size.  It will update the current
1775 * pointer, wake up sleepers, etc.
1776 *
1777 * Even if more than one periods have elapsed since the last call, you
1778 * have to call this only once.
1779 */
1780void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1781{
1782        struct snd_pcm_runtime *runtime;
1783        unsigned long flags;
1784
1785        if (snd_BUG_ON(!substream))
1786                return;
1787
1788        snd_pcm_stream_lock_irqsave(substream, flags);
1789        if (PCM_RUNTIME_CHECK(substream))
1790                goto _unlock;
1791        runtime = substream->runtime;
1792
1793        if (!snd_pcm_running(substream) ||
1794            snd_pcm_update_hw_ptr0(substream, 1) < 0)
1795                goto _end;
1796
1797#ifdef CONFIG_SND_PCM_TIMER
1798        if (substream->timer_running)
1799                snd_timer_interrupt(substream->timer, 1);
1800#endif
1801 _end:
1802        kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1803 _unlock:
1804        snd_pcm_stream_unlock_irqrestore(substream, flags);
1805}
1806EXPORT_SYMBOL(snd_pcm_period_elapsed);
1807
1808/*
1809 * Wait until avail_min data becomes available
1810 * Returns a negative error code if any error occurs during operation.
1811 * The available space is stored on availp.  When err = 0 and avail = 0
1812 * on the capture stream, it indicates the stream is in DRAINING state.
1813 */
1814static int wait_for_avail(struct snd_pcm_substream *substream,
1815                              snd_pcm_uframes_t *availp)
1816{
1817        struct snd_pcm_runtime *runtime = substream->runtime;
1818        int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1819        wait_queue_entry_t wait;
1820        int err = 0;
1821        snd_pcm_uframes_t avail = 0;
1822        long wait_time, tout;
1823
1824        init_waitqueue_entry(&wait, current);
1825        set_current_state(TASK_INTERRUPTIBLE);
1826        add_wait_queue(&runtime->tsleep, &wait);
1827
1828        if (runtime->no_period_wakeup)
1829                wait_time = MAX_SCHEDULE_TIMEOUT;
1830        else {
1831                /* use wait time from substream if available */
1832                if (substream->wait_time) {
1833                        wait_time = substream->wait_time;
1834                } else {
1835                        wait_time = 10;
1836
1837                        if (runtime->rate) {
1838                                long t = runtime->period_size * 2 /
1839                                         runtime->rate;
1840                                wait_time = max(t, wait_time);
1841                        }
1842                        wait_time = msecs_to_jiffies(wait_time * 1000);
1843                }
1844        }
1845
1846        for (;;) {
1847                if (signal_pending(current)) {
1848                        err = -ERESTARTSYS;
1849                        break;
1850                }
1851
1852                /*
1853                 * We need to check if space became available already
1854                 * (and thus the wakeup happened already) first to close
1855                 * the race of space already having become available.
1856                 * This check must happen after been added to the waitqueue
1857                 * and having current state be INTERRUPTIBLE.
1858                 */
1859                avail = snd_pcm_avail(substream);
1860                if (avail >= runtime->twake)
1861                        break;
1862                snd_pcm_stream_unlock_irq(substream);
1863
1864                tout = schedule_timeout(wait_time);
1865
1866                snd_pcm_stream_lock_irq(substream);
1867                set_current_state(TASK_INTERRUPTIBLE);
1868                switch (runtime->status->state) {
1869                case SNDRV_PCM_STATE_SUSPENDED:
1870                        err = -ESTRPIPE;
1871                        goto _endloop;
1872                case SNDRV_PCM_STATE_XRUN:
1873                        err = -EPIPE;
1874                        goto _endloop;
1875                case SNDRV_PCM_STATE_DRAINING:
1876                        if (is_playback)
1877                                err = -EPIPE;
1878                        else 
1879                                avail = 0; /* indicate draining */
1880                        goto _endloop;
1881                case SNDRV_PCM_STATE_OPEN:
1882                case SNDRV_PCM_STATE_SETUP:
1883                case SNDRV_PCM_STATE_DISCONNECTED:
1884                        err = -EBADFD;
1885                        goto _endloop;
1886                case SNDRV_PCM_STATE_PAUSED:
1887                        continue;
1888                }
1889                if (!tout) {
1890                        pcm_dbg(substream->pcm,
1891                                "%s write error (DMA or IRQ trouble?)\n",
1892                                is_playback ? "playback" : "capture");
1893                        err = -EIO;
1894                        break;
1895                }
1896        }
1897 _endloop:
1898        set_current_state(TASK_RUNNING);
1899        remove_wait_queue(&runtime->tsleep, &wait);
1900        *availp = avail;
1901        return err;
1902}
1903        
1904typedef int (*pcm_transfer_f)(struct snd_pcm_substream *substream,
1905                              int channel, unsigned long hwoff,
1906                              void *buf, unsigned long bytes);
1907
1908typedef int (*pcm_copy_f)(struct snd_pcm_substream *, snd_pcm_uframes_t, void *,
1909                          snd_pcm_uframes_t, snd_pcm_uframes_t, pcm_transfer_f);
1910
1911/* calculate the target DMA-buffer position to be written/read */
1912static void *get_dma_ptr(struct snd_pcm_runtime *runtime,
1913                           int channel, unsigned long hwoff)
1914{
1915        return runtime->dma_area + hwoff +
1916                channel * (runtime->dma_bytes / runtime->channels);
1917}
1918
1919/* default copy_user ops for write; used for both interleaved and non- modes */
1920static int default_write_copy(struct snd_pcm_substream *substream,
1921                              int channel, unsigned long hwoff,
1922                              void *buf, unsigned long bytes)
1923{
1924        if (copy_from_user(get_dma_ptr(substream->runtime, channel, hwoff),
1925                           (void __user *)buf, bytes))
1926                return -EFAULT;
1927        return 0;
1928}
1929
1930/* default copy_kernel ops for write */
1931static int default_write_copy_kernel(struct snd_pcm_substream *substream,
1932                                     int channel, unsigned long hwoff,
1933                                     void *buf, unsigned long bytes)
1934{
1935        memcpy(get_dma_ptr(substream->runtime, channel, hwoff), buf, bytes);
1936        return 0;
1937}
1938
1939/* fill silence instead of copy data; called as a transfer helper
1940 * from __snd_pcm_lib_write() or directly from noninterleaved_copy() when
1941 * a NULL buffer is passed
1942 */
1943static int fill_silence(struct snd_pcm_substream *substream, int channel,
1944                        unsigned long hwoff, void *buf, unsigned long bytes)
1945{
1946        struct snd_pcm_runtime *runtime = substream->runtime;
1947
1948        if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
1949                return 0;
1950        if (substream->ops->fill_silence)
1951                return substream->ops->fill_silence(substream, channel,
1952                                                    hwoff, bytes);
1953
1954        snd_pcm_format_set_silence(runtime->format,
1955                                   get_dma_ptr(runtime, channel, hwoff),
1956                                   bytes_to_samples(runtime, bytes));
1957        return 0;
1958}
1959
1960/* default copy_user ops for read; used for both interleaved and non- modes */
1961static int default_read_copy(struct snd_pcm_substream *substream,
1962                             int channel, unsigned long hwoff,
1963                             void *buf, unsigned long bytes)
1964{
1965        if (copy_to_user((void __user *)buf,
1966                         get_dma_ptr(substream->runtime, channel, hwoff),
1967                         bytes))
1968                return -EFAULT;
1969        return 0;
1970}
1971
1972/* default copy_kernel ops for read */
1973static int default_read_copy_kernel(struct snd_pcm_substream *substream,
1974                                    int channel, unsigned long hwoff,
1975                                    void *buf, unsigned long bytes)
1976{
1977        memcpy(buf, get_dma_ptr(substream->runtime, channel, hwoff), bytes);
1978        return 0;
1979}
1980
1981/* call transfer function with the converted pointers and sizes;
1982 * for interleaved mode, it's one shot for all samples
1983 */
1984static int interleaved_copy(struct snd_pcm_substream *substream,
1985                            snd_pcm_uframes_t hwoff, void *data,
1986                            snd_pcm_uframes_t off,
1987                            snd_pcm_uframes_t frames,
1988                            pcm_transfer_f transfer)
1989{
1990        struct snd_pcm_runtime *runtime = substream->runtime;
1991
1992        /* convert to bytes */
1993        hwoff = frames_to_bytes(runtime, hwoff);
1994        off = frames_to_bytes(runtime, off);
1995        frames = frames_to_bytes(runtime, frames);
1996        return transfer(substream, 0, hwoff, data + off, frames);
1997}
1998
1999/* call transfer function with the converted pointers and sizes for each
2000 * non-interleaved channel; when buffer is NULL, silencing instead of copying
2001 */
2002static int noninterleaved_copy(struct snd_pcm_substream *substream,
2003                               snd_pcm_uframes_t hwoff, void *data,
2004                               snd_pcm_uframes_t off,
2005                               snd_pcm_uframes_t frames,
2006                               pcm_transfer_f transfer)
2007{
2008        struct snd_pcm_runtime *runtime = substream->runtime;
2009        int channels = runtime->channels;
2010        void **bufs = data;
2011        int c, err;
2012
2013        /* convert to bytes; note that it's not frames_to_bytes() here.
2014         * in non-interleaved mode, we copy for each channel, thus
2015         * each copy is n_samples bytes x channels = whole frames.
2016         */
2017        off = samples_to_bytes(runtime, off);
2018        frames = samples_to_bytes(runtime, frames);
2019        hwoff = samples_to_bytes(runtime, hwoff);
2020        for (c = 0; c < channels; ++c, ++bufs) {
2021                if (!data || !*bufs)
2022                        err = fill_silence(substream, c, hwoff, NULL, frames);
2023                else
2024                        err = transfer(substream, c, hwoff, *bufs + off,
2025                                       frames);
2026                if (err < 0)
2027                        return err;
2028        }
2029        return 0;
2030}
2031
2032/* fill silence on the given buffer position;
2033 * called from snd_pcm_playback_silence()
2034 */
2035static int fill_silence_frames(struct snd_pcm_substream *substream,
2036                               snd_pcm_uframes_t off, snd_pcm_uframes_t frames)
2037{
2038        if (substream->runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
2039            substream->runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED)
2040                return interleaved_copy(substream, off, NULL, 0, frames,
2041                                        fill_silence);
2042        else
2043                return noninterleaved_copy(substream, off, NULL, 0, frames,
2044                                           fill_silence);
2045}
2046
2047/* sanity-check for read/write methods */
2048static int pcm_sanity_check(struct snd_pcm_substream *substream)
2049{
2050        struct snd_pcm_runtime *runtime;
2051        if (PCM_RUNTIME_CHECK(substream))
2052                return -ENXIO;
2053        runtime = substream->runtime;
2054        if (snd_BUG_ON(!substream->ops->copy_user && !runtime->dma_area))
2055                return -EINVAL;
2056        if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2057                return -EBADFD;
2058        return 0;
2059}
2060
2061static int pcm_accessible_state(struct snd_pcm_runtime *runtime)
2062{
2063        switch (runtime->status->state) {
2064        case SNDRV_PCM_STATE_PREPARED:
2065        case SNDRV_PCM_STATE_RUNNING:
2066        case SNDRV_PCM_STATE_PAUSED:
2067                return 0;
2068        case SNDRV_PCM_STATE_XRUN:
2069                return -EPIPE;
2070        case SNDRV_PCM_STATE_SUSPENDED:
2071                return -ESTRPIPE;
2072        default:
2073                return -EBADFD;
2074        }
2075}
2076
2077/* update to the given appl_ptr and call ack callback if needed;
2078 * when an error is returned, take back to the original value
2079 */
2080int pcm_lib_apply_appl_ptr(struct snd_pcm_substream *substream,
2081                           snd_pcm_uframes_t appl_ptr)
2082{
2083        struct snd_pcm_runtime *runtime = substream->runtime;
2084        snd_pcm_uframes_t old_appl_ptr = runtime->control->appl_ptr;
2085        int ret;
2086
2087        if (old_appl_ptr == appl_ptr)
2088                return 0;
2089
2090        runtime->control->appl_ptr = appl_ptr;
2091        if (substream->ops->ack) {
2092                ret = substream->ops->ack(substream);
2093                if (ret < 0) {
2094                        runtime->control->appl_ptr = old_appl_ptr;
2095                        return ret;
2096                }
2097        }
2098
2099        trace_applptr(substream, old_appl_ptr, appl_ptr);
2100
2101        return 0;
2102}
2103
2104/* the common loop for read/write data */
2105snd_pcm_sframes_t __snd_pcm_lib_xfer(struct snd_pcm_substream *substream,
2106                                     void *data, bool interleaved,
2107                                     snd_pcm_uframes_t size, bool in_kernel)
2108{
2109        struct snd_pcm_runtime *runtime = substream->runtime;
2110        snd_pcm_uframes_t xfer = 0;
2111        snd_pcm_uframes_t offset = 0;
2112        snd_pcm_uframes_t avail;
2113        pcm_copy_f writer;
2114        pcm_transfer_f transfer;
2115        bool nonblock;
2116        bool is_playback;
2117        int err;
2118
2119        err = pcm_sanity_check(substream);
2120        if (err < 0)
2121                return err;
2122
2123        is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
2124        if (interleaved) {
2125                if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2126                    runtime->channels > 1)
2127                        return -EINVAL;
2128                writer = interleaved_copy;
2129        } else {
2130                if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2131                        return -EINVAL;
2132                writer = noninterleaved_copy;
2133        }
2134
2135        if (!data) {
2136                if (is_playback)
2137                        transfer = fill_silence;
2138                else
2139                        return -EINVAL;
2140        } else if (in_kernel) {
2141                if (substream->ops->copy_kernel)
2142                        transfer = substream->ops->copy_kernel;
2143                else
2144                        transfer = is_playback ?
2145                                default_write_copy_kernel : default_read_copy_kernel;
2146        } else {
2147                if (substream->ops->copy_user)
2148                        transfer = (pcm_transfer_f)substream->ops->copy_user;
2149                else
2150                        transfer = is_playback ?
2151                                default_write_copy : default_read_copy;
2152        }
2153
2154        if (size == 0)
2155                return 0;
2156
2157        nonblock = !!(substream->f_flags & O_NONBLOCK);
2158
2159        snd_pcm_stream_lock_irq(substream);
2160        err = pcm_accessible_state(runtime);
2161        if (err < 0)
2162                goto _end_unlock;
2163
2164        runtime->twake = runtime->control->avail_min ? : 1;
2165        if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2166                snd_pcm_update_hw_ptr(substream);
2167
2168        /*
2169         * If size < start_threshold, wait indefinitely. Another
2170         * thread may start capture
2171         */
2172        if (!is_playback &&
2173            runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2174            size >= runtime->start_threshold) {
2175                err = snd_pcm_start(substream);
2176                if (err < 0)
2177                        goto _end_unlock;
2178        }
2179
2180        avail = snd_pcm_avail(substream);
2181
2182        while (size > 0) {
2183                snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2184                snd_pcm_uframes_t cont;
2185                if (!avail) {
2186                        if (!is_playback &&
2187                            runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
2188                                snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2189                                goto _end_unlock;
2190                        }
2191                        if (nonblock) {
2192                                err = -EAGAIN;
2193                                goto _end_unlock;
2194                        }
2195                        runtime->twake = min_t(snd_pcm_uframes_t, size,
2196                                        runtime->control->avail_min ? : 1);
2197                        err = wait_for_avail(substream, &avail);
2198                        if (err < 0)
2199                                goto _end_unlock;
2200                        if (!avail)
2201                                continue; /* draining */
2202                }
2203                frames = size > avail ? avail : size;
2204                appl_ptr = READ_ONCE(runtime->control->appl_ptr);
2205                appl_ofs = appl_ptr % runtime->buffer_size;
2206                cont = runtime->buffer_size - appl_ofs;
2207                if (frames > cont)
2208                        frames = cont;
2209                if (snd_BUG_ON(!frames)) {
2210                        err = -EINVAL;
2211                        goto _end_unlock;
2212                }
2213                snd_pcm_stream_unlock_irq(substream);
2214                err = writer(substream, appl_ofs, data, offset, frames,
2215                             transfer);
2216                snd_pcm_stream_lock_irq(substream);
2217                if (err < 0)
2218                        goto _end_unlock;
2219                err = pcm_accessible_state(runtime);
2220                if (err < 0)
2221                        goto _end_unlock;
2222                appl_ptr += frames;
2223                if (appl_ptr >= runtime->boundary)
2224                        appl_ptr -= runtime->boundary;
2225                err = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2226                if (err < 0)
2227                        goto _end_unlock;
2228
2229                offset += frames;
2230                size -= frames;
2231                xfer += frames;
2232                avail -= frames;
2233                if (is_playback &&
2234                    runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2235                    snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2236                        err = snd_pcm_start(substream);
2237                        if (err < 0)
2238                                goto _end_unlock;
2239                }
2240        }
2241 _end_unlock:
2242        runtime->twake = 0;
2243        if (xfer > 0 && err >= 0)
2244                snd_pcm_update_state(substream, runtime);
2245        snd_pcm_stream_unlock_irq(substream);
2246        return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2247}
2248EXPORT_SYMBOL(__snd_pcm_lib_xfer);
2249
2250/*
2251 * standard channel mapping helpers
2252 */
2253
2254/* default channel maps for multi-channel playbacks, up to 8 channels */
2255const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2256        { .channels = 1,
2257          .map = { SNDRV_CHMAP_MONO } },
2258        { .channels = 2,
2259          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2260        { .channels = 4,
2261          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2262                   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2263        { .channels = 6,
2264          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2265                   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2266                   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2267        { .channels = 8,
2268          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2269                   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2270                   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2271                   SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2272        { }
2273};
2274EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2275
2276/* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2277const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2278        { .channels = 1,
2279          .map = { SNDRV_CHMAP_MONO } },
2280        { .channels = 2,
2281          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2282        { .channels = 4,
2283          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2284                   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2285        { .channels = 6,
2286          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2287                   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2288                   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2289        { .channels = 8,
2290          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2291                   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2292                   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2293                   SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2294        { }
2295};
2296EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2297
2298static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2299{
2300        if (ch > info->max_channels)
2301                return false;
2302        return !info->channel_mask || (info->channel_mask & (1U << ch));
2303}
2304
2305static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2306                              struct snd_ctl_elem_info *uinfo)
2307{
2308        struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2309
2310        uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2311        uinfo->count = 0;
2312        uinfo->count = info->max_channels;
2313        uinfo->value.integer.min = 0;
2314        uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2315        return 0;
2316}
2317
2318/* get callback for channel map ctl element
2319 * stores the channel position firstly matching with the current channels
2320 */
2321static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2322                             struct snd_ctl_elem_value *ucontrol)
2323{
2324        struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2325        unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2326        struct snd_pcm_substream *substream;
2327        const struct snd_pcm_chmap_elem *map;
2328
2329        if (!info->chmap)
2330                return -EINVAL;
2331        substream = snd_pcm_chmap_substream(info, idx);
2332        if (!substream)
2333                return -ENODEV;
2334        memset(ucontrol->value.integer.value, 0,
2335               sizeof(ucontrol->value.integer.value));
2336        if (!substream->runtime)
2337                return 0; /* no channels set */
2338        for (map = info->chmap; map->channels; map++) {
2339                int i;
2340                if (map->channels == substream->runtime->channels &&
2341                    valid_chmap_channels(info, map->channels)) {
2342                        for (i = 0; i < map->channels; i++)
2343                                ucontrol->value.integer.value[i] = map->map[i];
2344                        return 0;
2345                }
2346        }
2347        return -EINVAL;
2348}
2349
2350/* tlv callback for channel map ctl element
2351 * expands the pre-defined channel maps in a form of TLV
2352 */
2353static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2354                             unsigned int size, unsigned int __user *tlv)
2355{
2356        struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2357        const struct snd_pcm_chmap_elem *map;
2358        unsigned int __user *dst;
2359        int c, count = 0;
2360
2361        if (!info->chmap)
2362                return -EINVAL;
2363        if (size < 8)
2364                return -ENOMEM;
2365        if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2366                return -EFAULT;
2367        size -= 8;
2368        dst = tlv + 2;
2369        for (map = info->chmap; map->channels; map++) {
2370                int chs_bytes = map->channels * 4;
2371                if (!valid_chmap_channels(info, map->channels))
2372                        continue;
2373                if (size < 8)
2374                        return -ENOMEM;
2375                if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2376                    put_user(chs_bytes, dst + 1))
2377                        return -EFAULT;
2378                dst += 2;
2379                size -= 8;
2380                count += 8;
2381                if (size < chs_bytes)
2382                        return -ENOMEM;
2383                size -= chs_bytes;
2384                count += chs_bytes;
2385                for (c = 0; c < map->channels; c++) {
2386                        if (put_user(map->map[c], dst))
2387                                return -EFAULT;
2388                        dst++;
2389                }
2390        }
2391        if (put_user(count, tlv + 1))
2392                return -EFAULT;
2393        return 0;
2394}
2395
2396static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2397{
2398        struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2399        info->pcm->streams[info->stream].chmap_kctl = NULL;
2400        kfree(info);
2401}
2402
2403/**
2404 * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2405 * @pcm: the assigned PCM instance
2406 * @stream: stream direction
2407 * @chmap: channel map elements (for query)
2408 * @max_channels: the max number of channels for the stream
2409 * @private_value: the value passed to each kcontrol's private_value field
2410 * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2411 *
2412 * Create channel-mapping control elements assigned to the given PCM stream(s).
2413 * Return: Zero if successful, or a negative error value.
2414 */
2415int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2416                           const struct snd_pcm_chmap_elem *chmap,
2417                           int max_channels,
2418                           unsigned long private_value,
2419                           struct snd_pcm_chmap **info_ret)
2420{
2421        struct snd_pcm_chmap *info;
2422        struct snd_kcontrol_new knew = {
2423                .iface = SNDRV_CTL_ELEM_IFACE_PCM,
2424                .access = SNDRV_CTL_ELEM_ACCESS_READ |
2425                        SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2426                        SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2427                .info = pcm_chmap_ctl_info,
2428                .get = pcm_chmap_ctl_get,
2429                .tlv.c = pcm_chmap_ctl_tlv,
2430        };
2431        int err;
2432
2433        if (WARN_ON(pcm->streams[stream].chmap_kctl))
2434                return -EBUSY;
2435        info = kzalloc(sizeof(*info), GFP_KERNEL);
2436        if (!info)
2437                return -ENOMEM;
2438        info->pcm = pcm;
2439        info->stream = stream;
2440        info->chmap = chmap;
2441        info->max_channels = max_channels;
2442        if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2443                knew.name = "Playback Channel Map";
2444        else
2445                knew.name = "Capture Channel Map";
2446        knew.device = pcm->device;
2447        knew.count = pcm->streams[stream].substream_count;
2448        knew.private_value = private_value;
2449        info->kctl = snd_ctl_new1(&knew, info);
2450        if (!info->kctl) {
2451                kfree(info);
2452                return -ENOMEM;
2453        }
2454        info->kctl->private_free = pcm_chmap_ctl_private_free;
2455        err = snd_ctl_add(pcm->card, info->kctl);
2456        if (err < 0)
2457                return err;
2458        pcm->streams[stream].chmap_kctl = info->kctl;
2459        if (info_ret)
2460                *info_ret = info;
2461        return 0;
2462}
2463EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);
2464