linux/sound/core/pcm_lib.c
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   1/*
   2 *  Digital Audio (PCM) abstract layer
   3 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   4 *                   Abramo Bagnara <abramo@alsa-project.org>
   5 *
   6 *
   7 *   This program is free software; you can redistribute it and/or modify
   8 *   it under the terms of the GNU General Public License as published by
   9 *   the Free Software Foundation; either version 2 of the License, or
  10 *   (at your option) any later version.
  11 *
  12 *   This program is distributed in the hope that it will be useful,
  13 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 *   GNU General Public License for more details.
  16 *
  17 *   You should have received a copy of the GNU General Public License
  18 *   along with this program; if not, write to the Free Software
  19 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  20 *
  21 */
  22
  23#include <linux/slab.h>
  24#include <linux/time.h>
  25#include <sound/core.h>
  26#include <sound/control.h>
  27#include <sound/info.h>
  28#include <sound/pcm.h>
  29#include <sound/pcm_params.h>
  30#include <sound/timer.h>
  31
  32/*
  33 * fill ring buffer with silence
  34 * runtime->silence_start: starting pointer to silence area
  35 * runtime->silence_filled: size filled with silence
  36 * runtime->silence_threshold: threshold from application
  37 * runtime->silence_size: maximal size from application
  38 *
  39 * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
  40 */
  41void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
  42{
  43        struct snd_pcm_runtime *runtime = substream->runtime;
  44        snd_pcm_uframes_t frames, ofs, transfer;
  45
  46        if (runtime->silence_size < runtime->boundary) {
  47                snd_pcm_sframes_t noise_dist, n;
  48                if (runtime->silence_start != runtime->control->appl_ptr) {
  49                        n = runtime->control->appl_ptr - runtime->silence_start;
  50                        if (n < 0)
  51                                n += runtime->boundary;
  52                        if ((snd_pcm_uframes_t)n < runtime->silence_filled)
  53                                runtime->silence_filled -= n;
  54                        else
  55                                runtime->silence_filled = 0;
  56                        runtime->silence_start = runtime->control->appl_ptr;
  57                }
  58                if (runtime->silence_filled >= runtime->buffer_size)
  59                        return;
  60                noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
  61                if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
  62                        return;
  63                frames = runtime->silence_threshold - noise_dist;
  64                if (frames > runtime->silence_size)
  65                        frames = runtime->silence_size;
  66        } else {
  67                if (new_hw_ptr == ULONG_MAX) {  /* initialization */
  68                        snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
  69                        runtime->silence_filled = avail > 0 ? avail : 0;
  70                        runtime->silence_start = (runtime->status->hw_ptr +
  71                                                  runtime->silence_filled) %
  72                                                 runtime->boundary;
  73                } else {
  74                        ofs = runtime->status->hw_ptr;
  75                        frames = new_hw_ptr - ofs;
  76                        if ((snd_pcm_sframes_t)frames < 0)
  77                                frames += runtime->boundary;
  78                        runtime->silence_filled -= frames;
  79                        if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
  80                                runtime->silence_filled = 0;
  81                                runtime->silence_start = new_hw_ptr;
  82                        } else {
  83                                runtime->silence_start = ofs;
  84                        }
  85                }
  86                frames = runtime->buffer_size - runtime->silence_filled;
  87        }
  88        if (snd_BUG_ON(frames > runtime->buffer_size))
  89                return;
  90        if (frames == 0)
  91                return;
  92        ofs = runtime->silence_start % runtime->buffer_size;
  93        while (frames > 0) {
  94                transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
  95                if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
  96                    runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
  97                        if (substream->ops->silence) {
  98                                int err;
  99                                err = substream->ops->silence(substream, -1, ofs, transfer);
 100                                snd_BUG_ON(err < 0);
 101                        } else {
 102                                char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
 103                                snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
 104                        }
 105                } else {
 106                        unsigned int c;
 107                        unsigned int channels = runtime->channels;
 108                        if (substream->ops->silence) {
 109                                for (c = 0; c < channels; ++c) {
 110                                        int err;
 111                                        err = substream->ops->silence(substream, c, ofs, transfer);
 112                                        snd_BUG_ON(err < 0);
 113                                }
 114                        } else {
 115                                size_t dma_csize = runtime->dma_bytes / channels;
 116                                for (c = 0; c < channels; ++c) {
 117                                        char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
 118                                        snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
 119                                }
 120                        }
 121                }
 122                runtime->silence_filled += transfer;
 123                frames -= transfer;
 124                ofs = 0;
 125        }
 126}
 127
 128static void xrun(struct snd_pcm_substream *substream)
 129{
 130        snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 131#ifdef CONFIG_SND_PCM_XRUN_DEBUG
 132        if (substream->pstr->xrun_debug) {
 133                snd_printd(KERN_DEBUG "XRUN: pcmC%dD%d%c\n",
 134                           substream->pcm->card->number,
 135                           substream->pcm->device,
 136                           substream->stream ? 'c' : 'p');
 137                if (substream->pstr->xrun_debug > 1)
 138                        dump_stack();
 139        }
 140#endif
 141}
 142
 143static inline snd_pcm_uframes_t snd_pcm_update_hw_ptr_pos(struct snd_pcm_substream *substream,
 144                                                          struct snd_pcm_runtime *runtime)
 145{
 146        snd_pcm_uframes_t pos;
 147
 148        if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
 149                snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 150        pos = substream->ops->pointer(substream);
 151        if (pos == SNDRV_PCM_POS_XRUN)
 152                return pos; /* XRUN */
 153#ifdef CONFIG_SND_DEBUG
 154        if (pos >= runtime->buffer_size) {
 155                snd_printk(KERN_ERR  "BUG: stream = %i, pos = 0x%lx, buffer size = 0x%lx, period size = 0x%lx\n", substream->stream, pos, runtime->buffer_size, runtime->period_size);
 156        }
 157#endif
 158        pos -= pos % runtime->min_align;
 159        return pos;
 160}
 161
 162static inline int snd_pcm_update_hw_ptr_post(struct snd_pcm_substream *substream,
 163                                             struct snd_pcm_runtime *runtime)
 164{
 165        snd_pcm_uframes_t avail;
 166
 167        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 168                avail = snd_pcm_playback_avail(runtime);
 169        else
 170                avail = snd_pcm_capture_avail(runtime);
 171        if (avail > runtime->avail_max)
 172                runtime->avail_max = avail;
 173        if (avail >= runtime->stop_threshold) {
 174                if (substream->runtime->status->state == SNDRV_PCM_STATE_DRAINING)
 175                        snd_pcm_drain_done(substream);
 176                else
 177                        xrun(substream);
 178                return -EPIPE;
 179        }
 180        if (avail >= runtime->control->avail_min)
 181                wake_up(&runtime->sleep);
 182        return 0;
 183}
 184
 185static inline int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream)
 186{
 187        struct snd_pcm_runtime *runtime = substream->runtime;
 188        snd_pcm_uframes_t pos;
 189        snd_pcm_uframes_t new_hw_ptr, hw_ptr_interrupt;
 190        snd_pcm_sframes_t delta;
 191
 192        pos = snd_pcm_update_hw_ptr_pos(substream, runtime);
 193        if (pos == SNDRV_PCM_POS_XRUN) {
 194                xrun(substream);
 195                return -EPIPE;
 196        }
 197        if (runtime->period_size == runtime->buffer_size)
 198                goto __next_buf;
 199        new_hw_ptr = runtime->hw_ptr_base + pos;
 200        hw_ptr_interrupt = runtime->hw_ptr_interrupt + runtime->period_size;
 201
 202        delta = hw_ptr_interrupt - new_hw_ptr;
 203        if (delta > 0) {
 204                if ((snd_pcm_uframes_t)delta < runtime->buffer_size / 2) {
 205#ifdef CONFIG_SND_PCM_XRUN_DEBUG
 206                        if (runtime->periods > 1 && substream->pstr->xrun_debug) {
 207                                snd_printd(KERN_ERR "Unexpected hw_pointer value [1] (stream = %i, delta: -%ld, max jitter = %ld): wrong interrupt acknowledge?\n", substream->stream, (long) delta, runtime->buffer_size / 2);
 208                                if (substream->pstr->xrun_debug > 1)
 209                                        dump_stack();
 210                        }
 211#endif
 212                        return 0;
 213                }
 214              __next_buf:
 215                runtime->hw_ptr_base += runtime->buffer_size;
 216                if (runtime->hw_ptr_base == runtime->boundary)
 217                        runtime->hw_ptr_base = 0;
 218                new_hw_ptr = runtime->hw_ptr_base + pos;
 219        }
 220
 221        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 222            runtime->silence_size > 0)
 223                snd_pcm_playback_silence(substream, new_hw_ptr);
 224
 225        runtime->status->hw_ptr = new_hw_ptr;
 226        runtime->hw_ptr_interrupt = new_hw_ptr - new_hw_ptr % runtime->period_size;
 227
 228        return snd_pcm_update_hw_ptr_post(substream, runtime);
 229}
 230
 231/* CAUTION: call it with irq disabled */
 232int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
 233{
 234        struct snd_pcm_runtime *runtime = substream->runtime;
 235        snd_pcm_uframes_t pos;
 236        snd_pcm_uframes_t old_hw_ptr, new_hw_ptr;
 237        snd_pcm_sframes_t delta;
 238
 239        old_hw_ptr = runtime->status->hw_ptr;
 240        pos = snd_pcm_update_hw_ptr_pos(substream, runtime);
 241        if (pos == SNDRV_PCM_POS_XRUN) {
 242                xrun(substream);
 243                return -EPIPE;
 244        }
 245        new_hw_ptr = runtime->hw_ptr_base + pos;
 246
 247        delta = old_hw_ptr - new_hw_ptr;
 248        if (delta > 0) {
 249                if ((snd_pcm_uframes_t)delta < runtime->buffer_size / 2) {
 250#ifdef CONFIG_SND_PCM_XRUN_DEBUG
 251                        if (runtime->periods > 2 && substream->pstr->xrun_debug) {
 252                                snd_printd(KERN_ERR "Unexpected hw_pointer value [2] (stream = %i, delta: -%ld, max jitter = %ld): wrong interrupt acknowledge?\n", substream->stream, (long) delta, runtime->buffer_size / 2);
 253                                if (substream->pstr->xrun_debug > 1)
 254                                        dump_stack();
 255                        }
 256#endif
 257                        return 0;
 258                }
 259                runtime->hw_ptr_base += runtime->buffer_size;
 260                if (runtime->hw_ptr_base == runtime->boundary)
 261                        runtime->hw_ptr_base = 0;
 262                new_hw_ptr = runtime->hw_ptr_base + pos;
 263        }
 264        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 265            runtime->silence_size > 0)
 266                snd_pcm_playback_silence(substream, new_hw_ptr);
 267
 268        runtime->status->hw_ptr = new_hw_ptr;
 269
 270        return snd_pcm_update_hw_ptr_post(substream, runtime);
 271}
 272
 273/**
 274 * snd_pcm_set_ops - set the PCM operators
 275 * @pcm: the pcm instance
 276 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
 277 * @ops: the operator table
 278 *
 279 * Sets the given PCM operators to the pcm instance.
 280 */
 281void snd_pcm_set_ops(struct snd_pcm *pcm, int direction, struct snd_pcm_ops *ops)
 282{
 283        struct snd_pcm_str *stream = &pcm->streams[direction];
 284        struct snd_pcm_substream *substream;
 285        
 286        for (substream = stream->substream; substream != NULL; substream = substream->next)
 287                substream->ops = ops;
 288}
 289
 290EXPORT_SYMBOL(snd_pcm_set_ops);
 291
 292/**
 293 * snd_pcm_sync - set the PCM sync id
 294 * @substream: the pcm substream
 295 *
 296 * Sets the PCM sync identifier for the card.
 297 */
 298void snd_pcm_set_sync(struct snd_pcm_substream *substream)
 299{
 300        struct snd_pcm_runtime *runtime = substream->runtime;
 301        
 302        runtime->sync.id32[0] = substream->pcm->card->number;
 303        runtime->sync.id32[1] = -1;
 304        runtime->sync.id32[2] = -1;
 305        runtime->sync.id32[3] = -1;
 306}
 307
 308EXPORT_SYMBOL(snd_pcm_set_sync);
 309
 310/*
 311 *  Standard ioctl routine
 312 */
 313
 314static inline unsigned int div32(unsigned int a, unsigned int b, 
 315                                 unsigned int *r)
 316{
 317        if (b == 0) {
 318                *r = 0;
 319                return UINT_MAX;
 320        }
 321        *r = a % b;
 322        return a / b;
 323}
 324
 325static inline unsigned int div_down(unsigned int a, unsigned int b)
 326{
 327        if (b == 0)
 328                return UINT_MAX;
 329        return a / b;
 330}
 331
 332static inline unsigned int div_up(unsigned int a, unsigned int b)
 333{
 334        unsigned int r;
 335        unsigned int q;
 336        if (b == 0)
 337                return UINT_MAX;
 338        q = div32(a, b, &r);
 339        if (r)
 340                ++q;
 341        return q;
 342}
 343
 344static inline unsigned int mul(unsigned int a, unsigned int b)
 345{
 346        if (a == 0)
 347                return 0;
 348        if (div_down(UINT_MAX, a) < b)
 349                return UINT_MAX;
 350        return a * b;
 351}
 352
 353static inline unsigned int muldiv32(unsigned int a, unsigned int b,
 354                                    unsigned int c, unsigned int *r)
 355{
 356        u_int64_t n = (u_int64_t) a * b;
 357        if (c == 0) {
 358                snd_BUG_ON(!n);
 359                *r = 0;
 360                return UINT_MAX;
 361        }
 362        div64_32(&n, c, r);
 363        if (n >= UINT_MAX) {
 364                *r = 0;
 365                return UINT_MAX;
 366        }
 367        return n;
 368}
 369
 370/**
 371 * snd_interval_refine - refine the interval value of configurator
 372 * @i: the interval value to refine
 373 * @v: the interval value to refer to
 374 *
 375 * Refines the interval value with the reference value.
 376 * The interval is changed to the range satisfying both intervals.
 377 * The interval status (min, max, integer, etc.) are evaluated.
 378 *
 379 * Returns non-zero if the value is changed, zero if not changed.
 380 */
 381int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
 382{
 383        int changed = 0;
 384        if (snd_BUG_ON(snd_interval_empty(i)))
 385                return -EINVAL;
 386        if (i->min < v->min) {
 387                i->min = v->min;
 388                i->openmin = v->openmin;
 389                changed = 1;
 390        } else if (i->min == v->min && !i->openmin && v->openmin) {
 391                i->openmin = 1;
 392                changed = 1;
 393        }
 394        if (i->max > v->max) {
 395                i->max = v->max;
 396                i->openmax = v->openmax;
 397                changed = 1;
 398        } else if (i->max == v->max && !i->openmax && v->openmax) {
 399                i->openmax = 1;
 400                changed = 1;
 401        }
 402        if (!i->integer && v->integer) {
 403                i->integer = 1;
 404                changed = 1;
 405        }
 406        if (i->integer) {
 407                if (i->openmin) {
 408                        i->min++;
 409                        i->openmin = 0;
 410                }
 411                if (i->openmax) {
 412                        i->max--;
 413                        i->openmax = 0;
 414                }
 415        } else if (!i->openmin && !i->openmax && i->min == i->max)
 416                i->integer = 1;
 417        if (snd_interval_checkempty(i)) {
 418                snd_interval_none(i);
 419                return -EINVAL;
 420        }
 421        return changed;
 422}
 423
 424EXPORT_SYMBOL(snd_interval_refine);
 425
 426static int snd_interval_refine_first(struct snd_interval *i)
 427{
 428        if (snd_BUG_ON(snd_interval_empty(i)))
 429                return -EINVAL;
 430        if (snd_interval_single(i))
 431                return 0;
 432        i->max = i->min;
 433        i->openmax = i->openmin;
 434        if (i->openmax)
 435                i->max++;
 436        return 1;
 437}
 438
 439static int snd_interval_refine_last(struct snd_interval *i)
 440{
 441        if (snd_BUG_ON(snd_interval_empty(i)))
 442                return -EINVAL;
 443        if (snd_interval_single(i))
 444                return 0;
 445        i->min = i->max;
 446        i->openmin = i->openmax;
 447        if (i->openmin)
 448                i->min--;
 449        return 1;
 450}
 451
 452void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 453{
 454        if (a->empty || b->empty) {
 455                snd_interval_none(c);
 456                return;
 457        }
 458        c->empty = 0;
 459        c->min = mul(a->min, b->min);
 460        c->openmin = (a->openmin || b->openmin);
 461        c->max = mul(a->max,  b->max);
 462        c->openmax = (a->openmax || b->openmax);
 463        c->integer = (a->integer && b->integer);
 464}
 465
 466/**
 467 * snd_interval_div - refine the interval value with division
 468 * @a: dividend
 469 * @b: divisor
 470 * @c: quotient
 471 *
 472 * c = a / b
 473 *
 474 * Returns non-zero if the value is changed, zero if not changed.
 475 */
 476void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 477{
 478        unsigned int r;
 479        if (a->empty || b->empty) {
 480                snd_interval_none(c);
 481                return;
 482        }
 483        c->empty = 0;
 484        c->min = div32(a->min, b->max, &r);
 485        c->openmin = (r || a->openmin || b->openmax);
 486        if (b->min > 0) {
 487                c->max = div32(a->max, b->min, &r);
 488                if (r) {
 489                        c->max++;
 490                        c->openmax = 1;
 491                } else
 492                        c->openmax = (a->openmax || b->openmin);
 493        } else {
 494                c->max = UINT_MAX;
 495                c->openmax = 0;
 496        }
 497        c->integer = 0;
 498}
 499
 500/**
 501 * snd_interval_muldivk - refine the interval value
 502 * @a: dividend 1
 503 * @b: dividend 2
 504 * @k: divisor (as integer)
 505 * @c: result
 506  *
 507 * c = a * b / k
 508 *
 509 * Returns non-zero if the value is changed, zero if not changed.
 510 */
 511void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
 512                      unsigned int k, struct snd_interval *c)
 513{
 514        unsigned int r;
 515        if (a->empty || b->empty) {
 516                snd_interval_none(c);
 517                return;
 518        }
 519        c->empty = 0;
 520        c->min = muldiv32(a->min, b->min, k, &r);
 521        c->openmin = (r || a->openmin || b->openmin);
 522        c->max = muldiv32(a->max, b->max, k, &r);
 523        if (r) {
 524                c->max++;
 525                c->openmax = 1;
 526        } else
 527                c->openmax = (a->openmax || b->openmax);
 528        c->integer = 0;
 529}
 530
 531/**
 532 * snd_interval_mulkdiv - refine the interval value
 533 * @a: dividend 1
 534 * @k: dividend 2 (as integer)
 535 * @b: divisor
 536 * @c: result
 537 *
 538 * c = a * k / b
 539 *
 540 * Returns non-zero if the value is changed, zero if not changed.
 541 */
 542void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
 543                      const struct snd_interval *b, struct snd_interval *c)
 544{
 545        unsigned int r;
 546        if (a->empty || b->empty) {
 547                snd_interval_none(c);
 548                return;
 549        }
 550        c->empty = 0;
 551        c->min = muldiv32(a->min, k, b->max, &r);
 552        c->openmin = (r || a->openmin || b->openmax);
 553        if (b->min > 0) {
 554                c->max = muldiv32(a->max, k, b->min, &r);
 555                if (r) {
 556                        c->max++;
 557                        c->openmax = 1;
 558                } else
 559                        c->openmax = (a->openmax || b->openmin);
 560        } else {
 561                c->max = UINT_MAX;
 562                c->openmax = 0;
 563        }
 564        c->integer = 0;
 565}
 566
 567/* ---- */
 568
 569
 570/**
 571 * snd_interval_ratnum - refine the interval value
 572 * @i: interval to refine
 573 * @rats_count: number of ratnum_t 
 574 * @rats: ratnum_t array
 575 * @nump: pointer to store the resultant numerator
 576 * @denp: pointer to store the resultant denominator
 577 *
 578 * Returns non-zero if the value is changed, zero if not changed.
 579 */
 580int snd_interval_ratnum(struct snd_interval *i,
 581                        unsigned int rats_count, struct snd_ratnum *rats,
 582                        unsigned int *nump, unsigned int *denp)
 583{
 584        unsigned int best_num, best_diff, best_den;
 585        unsigned int k;
 586        struct snd_interval t;
 587        int err;
 588
 589        best_num = best_den = best_diff = 0;
 590        for (k = 0; k < rats_count; ++k) {
 591                unsigned int num = rats[k].num;
 592                unsigned int den;
 593                unsigned int q = i->min;
 594                int diff;
 595                if (q == 0)
 596                        q = 1;
 597                den = div_down(num, q);
 598                if (den < rats[k].den_min)
 599                        continue;
 600                if (den > rats[k].den_max)
 601                        den = rats[k].den_max;
 602                else {
 603                        unsigned int r;
 604                        r = (den - rats[k].den_min) % rats[k].den_step;
 605                        if (r != 0)
 606                                den -= r;
 607                }
 608                diff = num - q * den;
 609                if (best_num == 0 ||
 610                    diff * best_den < best_diff * den) {
 611                        best_diff = diff;
 612                        best_den = den;
 613                        best_num = num;
 614                }
 615        }
 616        if (best_den == 0) {
 617                i->empty = 1;
 618                return -EINVAL;
 619        }
 620        t.min = div_down(best_num, best_den);
 621        t.openmin = !!(best_num % best_den);
 622        
 623        best_num = best_den = best_diff = 0;
 624        for (k = 0; k < rats_count; ++k) {
 625                unsigned int num = rats[k].num;
 626                unsigned int den;
 627                unsigned int q = i->max;
 628                int diff;
 629                if (q == 0) {
 630                        i->empty = 1;
 631                        return -EINVAL;
 632                }
 633                den = div_up(num, q);
 634                if (den > rats[k].den_max)
 635                        continue;
 636                if (den < rats[k].den_min)
 637                        den = rats[k].den_min;
 638                else {
 639                        unsigned int r;
 640                        r = (den - rats[k].den_min) % rats[k].den_step;
 641                        if (r != 0)
 642                                den += rats[k].den_step - r;
 643                }
 644                diff = q * den - num;
 645                if (best_num == 0 ||
 646                    diff * best_den < best_diff * den) {
 647                        best_diff = diff;
 648                        best_den = den;
 649                        best_num = num;
 650                }
 651        }
 652        if (best_den == 0) {
 653                i->empty = 1;
 654                return -EINVAL;
 655        }
 656        t.max = div_up(best_num, best_den);
 657        t.openmax = !!(best_num % best_den);
 658        t.integer = 0;
 659        err = snd_interval_refine(i, &t);
 660        if (err < 0)
 661                return err;
 662
 663        if (snd_interval_single(i)) {
 664                if (nump)
 665                        *nump = best_num;
 666                if (denp)
 667                        *denp = best_den;
 668        }
 669        return err;
 670}
 671
 672EXPORT_SYMBOL(snd_interval_ratnum);
 673
 674/**
 675 * snd_interval_ratden - refine the interval value
 676 * @i: interval to refine
 677 * @rats_count: number of struct ratden
 678 * @rats: struct ratden array
 679 * @nump: pointer to store the resultant numerator
 680 * @denp: pointer to store the resultant denominator
 681 *
 682 * Returns non-zero if the value is changed, zero if not changed.
 683 */
 684static int snd_interval_ratden(struct snd_interval *i,
 685                               unsigned int rats_count, struct snd_ratden *rats,
 686                               unsigned int *nump, unsigned int *denp)
 687{
 688        unsigned int best_num, best_diff, best_den;
 689        unsigned int k;
 690        struct snd_interval t;
 691        int err;
 692
 693        best_num = best_den = best_diff = 0;
 694        for (k = 0; k < rats_count; ++k) {
 695                unsigned int num;
 696                unsigned int den = rats[k].den;
 697                unsigned int q = i->min;
 698                int diff;
 699                num = mul(q, den);
 700                if (num > rats[k].num_max)
 701                        continue;
 702                if (num < rats[k].num_min)
 703                        num = rats[k].num_max;
 704                else {
 705                        unsigned int r;
 706                        r = (num - rats[k].num_min) % rats[k].num_step;
 707                        if (r != 0)
 708                                num += rats[k].num_step - r;
 709                }
 710                diff = num - q * den;
 711                if (best_num == 0 ||
 712                    diff * best_den < best_diff * den) {
 713                        best_diff = diff;
 714                        best_den = den;
 715                        best_num = num;
 716                }
 717        }
 718        if (best_den == 0) {
 719                i->empty = 1;
 720                return -EINVAL;
 721        }
 722        t.min = div_down(best_num, best_den);
 723        t.openmin = !!(best_num % best_den);
 724        
 725        best_num = best_den = best_diff = 0;
 726        for (k = 0; k < rats_count; ++k) {
 727                unsigned int num;
 728                unsigned int den = rats[k].den;
 729                unsigned int q = i->max;
 730                int diff;
 731                num = mul(q, den);
 732                if (num < rats[k].num_min)
 733                        continue;
 734                if (num > rats[k].num_max)
 735                        num = rats[k].num_max;
 736                else {
 737                        unsigned int r;
 738                        r = (num - rats[k].num_min) % rats[k].num_step;
 739                        if (r != 0)
 740                                num -= r;
 741                }
 742                diff = q * den - num;
 743                if (best_num == 0 ||
 744                    diff * best_den < best_diff * den) {
 745                        best_diff = diff;
 746                        best_den = den;
 747                        best_num = num;
 748                }
 749        }
 750        if (best_den == 0) {
 751                i->empty = 1;
 752                return -EINVAL;
 753        }
 754        t.max = div_up(best_num, best_den);
 755        t.openmax = !!(best_num % best_den);
 756        t.integer = 0;
 757        err = snd_interval_refine(i, &t);
 758        if (err < 0)
 759                return err;
 760
 761        if (snd_interval_single(i)) {
 762                if (nump)
 763                        *nump = best_num;
 764                if (denp)
 765                        *denp = best_den;
 766        }
 767        return err;
 768}
 769
 770/**
 771 * snd_interval_list - refine the interval value from the list
 772 * @i: the interval value to refine
 773 * @count: the number of elements in the list
 774 * @list: the value list
 775 * @mask: the bit-mask to evaluate
 776 *
 777 * Refines the interval value from the list.
 778 * When mask is non-zero, only the elements corresponding to bit 1 are
 779 * evaluated.
 780 *
 781 * Returns non-zero if the value is changed, zero if not changed.
 782 */
 783int snd_interval_list(struct snd_interval *i, unsigned int count, unsigned int *list, unsigned int mask)
 784{
 785        unsigned int k;
 786        int changed = 0;
 787
 788        if (!count) {
 789                i->empty = 1;
 790                return -EINVAL;
 791        }
 792        for (k = 0; k < count; k++) {
 793                if (mask && !(mask & (1 << k)))
 794                        continue;
 795                if (i->min == list[k] && !i->openmin)
 796                        goto _l1;
 797                if (i->min < list[k]) {
 798                        i->min = list[k];
 799                        i->openmin = 0;
 800                        changed = 1;
 801                        goto _l1;
 802                }
 803        }
 804        i->empty = 1;
 805        return -EINVAL;
 806 _l1:
 807        for (k = count; k-- > 0;) {
 808                if (mask && !(mask & (1 << k)))
 809                        continue;
 810                if (i->max == list[k] && !i->openmax)
 811                        goto _l2;
 812                if (i->max > list[k]) {
 813                        i->max = list[k];
 814                        i->openmax = 0;
 815                        changed = 1;
 816                        goto _l2;
 817                }
 818        }
 819        i->empty = 1;
 820        return -EINVAL;
 821 _l2:
 822        if (snd_interval_checkempty(i)) {
 823                i->empty = 1;
 824                return -EINVAL;
 825        }
 826        return changed;
 827}
 828
 829EXPORT_SYMBOL(snd_interval_list);
 830
 831static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
 832{
 833        unsigned int n;
 834        int changed = 0;
 835        n = (i->min - min) % step;
 836        if (n != 0 || i->openmin) {
 837                i->min += step - n;
 838                changed = 1;
 839        }
 840        n = (i->max - min) % step;
 841        if (n != 0 || i->openmax) {
 842                i->max -= n;
 843                changed = 1;
 844        }
 845        if (snd_interval_checkempty(i)) {
 846                i->empty = 1;
 847                return -EINVAL;
 848        }
 849        return changed;
 850}
 851
 852/* Info constraints helpers */
 853
 854/**
 855 * snd_pcm_hw_rule_add - add the hw-constraint rule
 856 * @runtime: the pcm runtime instance
 857 * @cond: condition bits
 858 * @var: the variable to evaluate
 859 * @func: the evaluation function
 860 * @private: the private data pointer passed to function
 861 * @dep: the dependent variables
 862 *
 863 * Returns zero if successful, or a negative error code on failure.
 864 */
 865int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
 866                        int var,
 867                        snd_pcm_hw_rule_func_t func, void *private,
 868                        int dep, ...)
 869{
 870        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
 871        struct snd_pcm_hw_rule *c;
 872        unsigned int k;
 873        va_list args;
 874        va_start(args, dep);
 875        if (constrs->rules_num >= constrs->rules_all) {
 876                struct snd_pcm_hw_rule *new;
 877                unsigned int new_rules = constrs->rules_all + 16;
 878                new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
 879                if (!new)
 880                        return -ENOMEM;
 881                if (constrs->rules) {
 882                        memcpy(new, constrs->rules,
 883                               constrs->rules_num * sizeof(*c));
 884                        kfree(constrs->rules);
 885                }
 886                constrs->rules = new;
 887                constrs->rules_all = new_rules;
 888        }
 889        c = &constrs->rules[constrs->rules_num];
 890        c->cond = cond;
 891        c->func = func;
 892        c->var = var;
 893        c->private = private;
 894        k = 0;
 895        while (1) {
 896                if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps)))
 897                        return -EINVAL;
 898                c->deps[k++] = dep;
 899                if (dep < 0)
 900                        break;
 901                dep = va_arg(args, int);
 902        }
 903        constrs->rules_num++;
 904        va_end(args);
 905        return 0;
 906}                                   
 907
 908EXPORT_SYMBOL(snd_pcm_hw_rule_add);
 909
 910/**
 911 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
 912 * @runtime: PCM runtime instance
 913 * @var: hw_params variable to apply the mask
 914 * @mask: the bitmap mask
 915 *
 916 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
 917 */
 918int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
 919                               u_int32_t mask)
 920{
 921        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
 922        struct snd_mask *maskp = constrs_mask(constrs, var);
 923        *maskp->bits &= mask;
 924        memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
 925        if (*maskp->bits == 0)
 926                return -EINVAL;
 927        return 0;
 928}
 929
 930/**
 931 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
 932 * @runtime: PCM runtime instance
 933 * @var: hw_params variable to apply the mask
 934 * @mask: the 64bit bitmap mask
 935 *
 936 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
 937 */
 938int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
 939                                 u_int64_t mask)
 940{
 941        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
 942        struct snd_mask *maskp = constrs_mask(constrs, var);
 943        maskp->bits[0] &= (u_int32_t)mask;
 944        maskp->bits[1] &= (u_int32_t)(mask >> 32);
 945        memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
 946        if (! maskp->bits[0] && ! maskp->bits[1])
 947                return -EINVAL;
 948        return 0;
 949}
 950
 951/**
 952 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
 953 * @runtime: PCM runtime instance
 954 * @var: hw_params variable to apply the integer constraint
 955 *
 956 * Apply the constraint of integer to an interval parameter.
 957 */
 958int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
 959{
 960        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
 961        return snd_interval_setinteger(constrs_interval(constrs, var));
 962}
 963
 964EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
 965
 966/**
 967 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
 968 * @runtime: PCM runtime instance
 969 * @var: hw_params variable to apply the range
 970 * @min: the minimal value
 971 * @max: the maximal value
 972 * 
 973 * Apply the min/max range constraint to an interval parameter.
 974 */
 975int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
 976                                 unsigned int min, unsigned int max)
 977{
 978        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
 979        struct snd_interval t;
 980        t.min = min;
 981        t.max = max;
 982        t.openmin = t.openmax = 0;
 983        t.integer = 0;
 984        return snd_interval_refine(constrs_interval(constrs, var), &t);
 985}
 986
 987EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
 988
 989static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
 990                                struct snd_pcm_hw_rule *rule)
 991{
 992        struct snd_pcm_hw_constraint_list *list = rule->private;
 993        return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
 994}               
 995
 996
 997/**
 998 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
 999 * @runtime: PCM runtime instance
1000 * @cond: condition bits
1001 * @var: hw_params variable to apply the list constraint
1002 * @l: list
1003 * 
1004 * Apply the list of constraints to an interval parameter.
1005 */
1006int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1007                               unsigned int cond,
1008                               snd_pcm_hw_param_t var,
1009                               struct snd_pcm_hw_constraint_list *l)
1010{
1011        return snd_pcm_hw_rule_add(runtime, cond, var,
1012                                   snd_pcm_hw_rule_list, l,
1013                                   var, -1);
1014}
1015
1016EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1017
1018static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1019                                   struct snd_pcm_hw_rule *rule)
1020{
1021        struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1022        unsigned int num = 0, den = 0;
1023        int err;
1024        err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1025                                  r->nrats, r->rats, &num, &den);
1026        if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1027                params->rate_num = num;
1028                params->rate_den = den;
1029        }
1030        return err;
1031}
1032
1033/**
1034 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1035 * @runtime: PCM runtime instance
1036 * @cond: condition bits
1037 * @var: hw_params variable to apply the ratnums constraint
1038 * @r: struct snd_ratnums constriants
1039 */
1040int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime, 
1041                                  unsigned int cond,
1042                                  snd_pcm_hw_param_t var,
1043                                  struct snd_pcm_hw_constraint_ratnums *r)
1044{
1045        return snd_pcm_hw_rule_add(runtime, cond, var,
1046                                   snd_pcm_hw_rule_ratnums, r,
1047                                   var, -1);
1048}
1049
1050EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1051
1052static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1053                                   struct snd_pcm_hw_rule *rule)
1054{
1055        struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1056        unsigned int num = 0, den = 0;
1057        int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1058                                  r->nrats, r->rats, &num, &den);
1059        if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1060                params->rate_num = num;
1061                params->rate_den = den;
1062        }
1063        return err;
1064}
1065
1066/**
1067 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1068 * @runtime: PCM runtime instance
1069 * @cond: condition bits
1070 * @var: hw_params variable to apply the ratdens constraint
1071 * @r: struct snd_ratdens constriants
1072 */
1073int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime, 
1074                                  unsigned int cond,
1075                                  snd_pcm_hw_param_t var,
1076                                  struct snd_pcm_hw_constraint_ratdens *r)
1077{
1078        return snd_pcm_hw_rule_add(runtime, cond, var,
1079                                   snd_pcm_hw_rule_ratdens, r,
1080                                   var, -1);
1081}
1082
1083EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1084
1085static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1086                                  struct snd_pcm_hw_rule *rule)
1087{
1088        unsigned int l = (unsigned long) rule->private;
1089        int width = l & 0xffff;
1090        unsigned int msbits = l >> 16;
1091        struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1092        if (snd_interval_single(i) && snd_interval_value(i) == width)
1093                params->msbits = msbits;
1094        return 0;
1095}
1096
1097/**
1098 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1099 * @runtime: PCM runtime instance
1100 * @cond: condition bits
1101 * @width: sample bits width
1102 * @msbits: msbits width
1103 */
1104int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime, 
1105                                 unsigned int cond,
1106                                 unsigned int width,
1107                                 unsigned int msbits)
1108{
1109        unsigned long l = (msbits << 16) | width;
1110        return snd_pcm_hw_rule_add(runtime, cond, -1,
1111                                    snd_pcm_hw_rule_msbits,
1112                                    (void*) l,
1113                                    SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1114}
1115
1116EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1117
1118static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1119                                struct snd_pcm_hw_rule *rule)
1120{
1121        unsigned long step = (unsigned long) rule->private;
1122        return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1123}
1124
1125/**
1126 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1127 * @runtime: PCM runtime instance
1128 * @cond: condition bits
1129 * @var: hw_params variable to apply the step constraint
1130 * @step: step size
1131 */
1132int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1133                               unsigned int cond,
1134                               snd_pcm_hw_param_t var,
1135                               unsigned long step)
1136{
1137        return snd_pcm_hw_rule_add(runtime, cond, var, 
1138                                   snd_pcm_hw_rule_step, (void *) step,
1139                                   var, -1);
1140}
1141
1142EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1143
1144static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1145{
1146        static unsigned int pow2_sizes[] = {
1147                1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1148                1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1149                1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1150                1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1151        };
1152        return snd_interval_list(hw_param_interval(params, rule->var),
1153                                 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1154}               
1155
1156/**
1157 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1158 * @runtime: PCM runtime instance
1159 * @cond: condition bits
1160 * @var: hw_params variable to apply the power-of-2 constraint
1161 */
1162int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1163                               unsigned int cond,
1164                               snd_pcm_hw_param_t var)
1165{
1166        return snd_pcm_hw_rule_add(runtime, cond, var, 
1167                                   snd_pcm_hw_rule_pow2, NULL,
1168                                   var, -1);
1169}
1170
1171EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1172
1173static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1174                                  snd_pcm_hw_param_t var)
1175{
1176        if (hw_is_mask(var)) {
1177                snd_mask_any(hw_param_mask(params, var));
1178                params->cmask |= 1 << var;
1179                params->rmask |= 1 << var;
1180                return;
1181        }
1182        if (hw_is_interval(var)) {
1183                snd_interval_any(hw_param_interval(params, var));
1184                params->cmask |= 1 << var;
1185                params->rmask |= 1 << var;
1186                return;
1187        }
1188        snd_BUG();
1189}
1190
1191void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1192{
1193        unsigned int k;
1194        memset(params, 0, sizeof(*params));
1195        for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1196                _snd_pcm_hw_param_any(params, k);
1197        for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1198                _snd_pcm_hw_param_any(params, k);
1199        params->info = ~0U;
1200}
1201
1202EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1203
1204/**
1205 * snd_pcm_hw_param_value - return @params field @var value
1206 * @params: the hw_params instance
1207 * @var: parameter to retrieve
1208 * @dir: pointer to the direction (-1,0,1) or %NULL
1209 *
1210 * Return the value for field @var if it's fixed in configuration space
1211 * defined by @params. Return -%EINVAL otherwise.
1212 */
1213int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1214                           snd_pcm_hw_param_t var, int *dir)
1215{
1216        if (hw_is_mask(var)) {
1217                const struct snd_mask *mask = hw_param_mask_c(params, var);
1218                if (!snd_mask_single(mask))
1219                        return -EINVAL;
1220                if (dir)
1221                        *dir = 0;
1222                return snd_mask_value(mask);
1223        }
1224        if (hw_is_interval(var)) {
1225                const struct snd_interval *i = hw_param_interval_c(params, var);
1226                if (!snd_interval_single(i))
1227                        return -EINVAL;
1228                if (dir)
1229                        *dir = i->openmin;
1230                return snd_interval_value(i);
1231        }
1232        return -EINVAL;
1233}
1234
1235EXPORT_SYMBOL(snd_pcm_hw_param_value);
1236
1237void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1238                                snd_pcm_hw_param_t var)
1239{
1240        if (hw_is_mask(var)) {
1241                snd_mask_none(hw_param_mask(params, var));
1242                params->cmask |= 1 << var;
1243                params->rmask |= 1 << var;
1244        } else if (hw_is_interval(var)) {
1245                snd_interval_none(hw_param_interval(params, var));
1246                params->cmask |= 1 << var;
1247                params->rmask |= 1 << var;
1248        } else {
1249                snd_BUG();
1250        }
1251}
1252
1253EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1254
1255static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1256                                   snd_pcm_hw_param_t var)
1257{
1258        int changed;
1259        if (hw_is_mask(var))
1260                changed = snd_mask_refine_first(hw_param_mask(params, var));
1261        else if (hw_is_interval(var))
1262                changed = snd_interval_refine_first(hw_param_interval(params, var));
1263        else
1264                return -EINVAL;
1265        if (changed) {
1266                params->cmask |= 1 << var;
1267                params->rmask |= 1 << var;
1268        }
1269        return changed;
1270}
1271
1272
1273/**
1274 * snd_pcm_hw_param_first - refine config space and return minimum value
1275 * @pcm: PCM instance
1276 * @params: the hw_params instance
1277 * @var: parameter to retrieve
1278 * @dir: pointer to the direction (-1,0,1) or %NULL
1279 *
1280 * Inside configuration space defined by @params remove from @var all
1281 * values > minimum. Reduce configuration space accordingly.
1282 * Return the minimum.
1283 */
1284int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm, 
1285                           struct snd_pcm_hw_params *params, 
1286                           snd_pcm_hw_param_t var, int *dir)
1287{
1288        int changed = _snd_pcm_hw_param_first(params, var);
1289        if (changed < 0)
1290                return changed;
1291        if (params->rmask) {
1292                int err = snd_pcm_hw_refine(pcm, params);
1293                if (snd_BUG_ON(err < 0))
1294                        return err;
1295        }
1296        return snd_pcm_hw_param_value(params, var, dir);
1297}
1298
1299EXPORT_SYMBOL(snd_pcm_hw_param_first);
1300
1301static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1302                                  snd_pcm_hw_param_t var)
1303{
1304        int changed;
1305        if (hw_is_mask(var))
1306                changed = snd_mask_refine_last(hw_param_mask(params, var));
1307        else if (hw_is_interval(var))
1308                changed = snd_interval_refine_last(hw_param_interval(params, var));
1309        else
1310                return -EINVAL;
1311        if (changed) {
1312                params->cmask |= 1 << var;
1313                params->rmask |= 1 << var;
1314        }
1315        return changed;
1316}
1317
1318
1319/**
1320 * snd_pcm_hw_param_last - refine config space and return maximum value
1321 * @pcm: PCM instance
1322 * @params: the hw_params instance
1323 * @var: parameter to retrieve
1324 * @dir: pointer to the direction (-1,0,1) or %NULL
1325 *
1326 * Inside configuration space defined by @params remove from @var all
1327 * values < maximum. Reduce configuration space accordingly.
1328 * Return the maximum.
1329 */
1330int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm, 
1331                          struct snd_pcm_hw_params *params,
1332                          snd_pcm_hw_param_t var, int *dir)
1333{
1334        int changed = _snd_pcm_hw_param_last(params, var);
1335        if (changed < 0)
1336                return changed;
1337        if (params->rmask) {
1338                int err = snd_pcm_hw_refine(pcm, params);
1339                if (snd_BUG_ON(err < 0))
1340                        return err;
1341        }
1342        return snd_pcm_hw_param_value(params, var, dir);
1343}
1344
1345EXPORT_SYMBOL(snd_pcm_hw_param_last);
1346
1347/**
1348 * snd_pcm_hw_param_choose - choose a configuration defined by @params
1349 * @pcm: PCM instance
1350 * @params: the hw_params instance
1351 *
1352 * Choose one configuration from configuration space defined by @params.
1353 * The configuration chosen is that obtained fixing in this order:
1354 * first access, first format, first subformat, min channels,
1355 * min rate, min period time, max buffer size, min tick time
1356 */
1357int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1358                             struct snd_pcm_hw_params *params)
1359{
1360        static int vars[] = {
1361                SNDRV_PCM_HW_PARAM_ACCESS,
1362                SNDRV_PCM_HW_PARAM_FORMAT,
1363                SNDRV_PCM_HW_PARAM_SUBFORMAT,
1364                SNDRV_PCM_HW_PARAM_CHANNELS,
1365                SNDRV_PCM_HW_PARAM_RATE,
1366                SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1367                SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1368                SNDRV_PCM_HW_PARAM_TICK_TIME,
1369                -1
1370        };
1371        int err, *v;
1372
1373        for (v = vars; *v != -1; v++) {
1374                if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1375                        err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1376                else
1377                        err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1378                if (snd_BUG_ON(err < 0))
1379                        return err;
1380        }
1381        return 0;
1382}
1383
1384static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1385                                   void *arg)
1386{
1387        struct snd_pcm_runtime *runtime = substream->runtime;
1388        unsigned long flags;
1389        snd_pcm_stream_lock_irqsave(substream, flags);
1390        if (snd_pcm_running(substream) &&
1391            snd_pcm_update_hw_ptr(substream) >= 0)
1392                runtime->status->hw_ptr %= runtime->buffer_size;
1393        else
1394                runtime->status->hw_ptr = 0;
1395        snd_pcm_stream_unlock_irqrestore(substream, flags);
1396        return 0;
1397}
1398
1399static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1400                                          void *arg)
1401{
1402        struct snd_pcm_channel_info *info = arg;
1403        struct snd_pcm_runtime *runtime = substream->runtime;
1404        int width;
1405        if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1406                info->offset = -1;
1407                return 0;
1408        }
1409        width = snd_pcm_format_physical_width(runtime->format);
1410        if (width < 0)
1411                return width;
1412        info->offset = 0;
1413        switch (runtime->access) {
1414        case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1415        case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1416                info->first = info->channel * width;
1417                info->step = runtime->channels * width;
1418                break;
1419        case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1420        case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1421        {
1422                size_t size = runtime->dma_bytes / runtime->channels;
1423                info->first = info->channel * size * 8;
1424                info->step = width;
1425                break;
1426        }
1427        default:
1428                snd_BUG();
1429                break;
1430        }
1431        return 0;
1432}
1433
1434/**
1435 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1436 * @substream: the pcm substream instance
1437 * @cmd: ioctl command
1438 * @arg: ioctl argument
1439 *
1440 * Processes the generic ioctl commands for PCM.
1441 * Can be passed as the ioctl callback for PCM ops.
1442 *
1443 * Returns zero if successful, or a negative error code on failure.
1444 */
1445int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1446                      unsigned int cmd, void *arg)
1447{
1448        switch (cmd) {
1449        case SNDRV_PCM_IOCTL1_INFO:
1450                return 0;
1451        case SNDRV_PCM_IOCTL1_RESET:
1452                return snd_pcm_lib_ioctl_reset(substream, arg);
1453        case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1454                return snd_pcm_lib_ioctl_channel_info(substream, arg);
1455        }
1456        return -ENXIO;
1457}
1458
1459EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1460
1461/**
1462 * snd_pcm_period_elapsed - update the pcm status for the next period
1463 * @substream: the pcm substream instance
1464 *
1465 * This function is called from the interrupt handler when the
1466 * PCM has processed the period size.  It will update the current
1467 * pointer, wake up sleepers, etc.
1468 *
1469 * Even if more than one periods have elapsed since the last call, you
1470 * have to call this only once.
1471 */
1472void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1473{
1474        struct snd_pcm_runtime *runtime;
1475        unsigned long flags;
1476
1477        if (PCM_RUNTIME_CHECK(substream))
1478                return;
1479        runtime = substream->runtime;
1480
1481        if (runtime->transfer_ack_begin)
1482                runtime->transfer_ack_begin(substream);
1483
1484        snd_pcm_stream_lock_irqsave(substream, flags);
1485        if (!snd_pcm_running(substream) ||
1486            snd_pcm_update_hw_ptr_interrupt(substream) < 0)
1487                goto _end;
1488
1489        if (substream->timer_running)
1490                snd_timer_interrupt(substream->timer, 1);
1491 _end:
1492        snd_pcm_stream_unlock_irqrestore(substream, flags);
1493        if (runtime->transfer_ack_end)
1494                runtime->transfer_ack_end(substream);
1495        kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1496}
1497
1498EXPORT_SYMBOL(snd_pcm_period_elapsed);
1499
1500/*
1501 * Wait until avail_min data becomes available
1502 * Returns a negative error code if any error occurs during operation.
1503 * The available space is stored on availp.  When err = 0 and avail = 0
1504 * on the capture stream, it indicates the stream is in DRAINING state.
1505 */
1506static int wait_for_avail_min(struct snd_pcm_substream *substream,
1507                              snd_pcm_uframes_t *availp)
1508{
1509        struct snd_pcm_runtime *runtime = substream->runtime;
1510        int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1511        wait_queue_t wait;
1512        int err = 0;
1513        snd_pcm_uframes_t avail = 0;
1514        long tout;
1515
1516        init_waitqueue_entry(&wait, current);
1517        add_wait_queue(&runtime->sleep, &wait);
1518        for (;;) {
1519                if (signal_pending(current)) {
1520                        err = -ERESTARTSYS;
1521                        break;
1522                }
1523                set_current_state(TASK_INTERRUPTIBLE);
1524                snd_pcm_stream_unlock_irq(substream);
1525                tout = schedule_timeout(msecs_to_jiffies(10000));
1526                snd_pcm_stream_lock_irq(substream);
1527                switch (runtime->status->state) {
1528                case SNDRV_PCM_STATE_SUSPENDED:
1529                        err = -ESTRPIPE;
1530                        goto _endloop;
1531                case SNDRV_PCM_STATE_XRUN:
1532                        err = -EPIPE;
1533                        goto _endloop;
1534                case SNDRV_PCM_STATE_DRAINING:
1535                        if (is_playback)
1536                                err = -EPIPE;
1537                        else 
1538                                avail = 0; /* indicate draining */
1539                        goto _endloop;
1540                case SNDRV_PCM_STATE_OPEN:
1541                case SNDRV_PCM_STATE_SETUP:
1542                case SNDRV_PCM_STATE_DISCONNECTED:
1543                        err = -EBADFD;
1544                        goto _endloop;
1545                }
1546                if (!tout) {
1547                        snd_printd("%s write error (DMA or IRQ trouble?)\n",
1548                                   is_playback ? "playback" : "capture");
1549                        err = -EIO;
1550                        break;
1551                }
1552                if (is_playback)
1553                        avail = snd_pcm_playback_avail(runtime);
1554                else
1555                        avail = snd_pcm_capture_avail(runtime);
1556                if (avail >= runtime->control->avail_min)
1557                        break;
1558        }
1559 _endloop:
1560        remove_wait_queue(&runtime->sleep, &wait);
1561        *availp = avail;
1562        return err;
1563}
1564        
1565static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1566                                      unsigned int hwoff,
1567                                      unsigned long data, unsigned int off,
1568                                      snd_pcm_uframes_t frames)
1569{
1570        struct snd_pcm_runtime *runtime = substream->runtime;
1571        int err;
1572        char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1573        if (substream->ops->copy) {
1574                if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1575                        return err;
1576        } else {
1577                char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1578                if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1579                        return -EFAULT;
1580        }
1581        return 0;
1582}
1583 
1584typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1585                          unsigned long data, unsigned int off,
1586                          snd_pcm_uframes_t size);
1587
1588static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream, 
1589                                            unsigned long data,
1590                                            snd_pcm_uframes_t size,
1591                                            int nonblock,
1592                                            transfer_f transfer)
1593{
1594        struct snd_pcm_runtime *runtime = substream->runtime;
1595        snd_pcm_uframes_t xfer = 0;
1596        snd_pcm_uframes_t offset = 0;
1597        int err = 0;
1598
1599        if (size == 0)
1600                return 0;
1601
1602        snd_pcm_stream_lock_irq(substream);
1603        switch (runtime->status->state) {
1604        case SNDRV_PCM_STATE_PREPARED:
1605        case SNDRV_PCM_STATE_RUNNING:
1606        case SNDRV_PCM_STATE_PAUSED:
1607                break;
1608        case SNDRV_PCM_STATE_XRUN:
1609                err = -EPIPE;
1610                goto _end_unlock;
1611        case SNDRV_PCM_STATE_SUSPENDED:
1612                err = -ESTRPIPE;
1613                goto _end_unlock;
1614        default:
1615                err = -EBADFD;
1616                goto _end_unlock;
1617        }
1618
1619        while (size > 0) {
1620                snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1621                snd_pcm_uframes_t avail;
1622                snd_pcm_uframes_t cont;
1623                if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1624                        snd_pcm_update_hw_ptr(substream);
1625                avail = snd_pcm_playback_avail(runtime);
1626                if (!avail) {
1627                        if (nonblock) {
1628                                err = -EAGAIN;
1629                                goto _end_unlock;
1630                        }
1631                        err = wait_for_avail_min(substream, &avail);
1632                        if (err < 0)
1633                                goto _end_unlock;
1634                }
1635                frames = size > avail ? avail : size;
1636                cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1637                if (frames > cont)
1638                        frames = cont;
1639                if (snd_BUG_ON(!frames)) {
1640                        snd_pcm_stream_unlock_irq(substream);
1641                        return -EINVAL;
1642                }
1643                appl_ptr = runtime->control->appl_ptr;
1644                appl_ofs = appl_ptr % runtime->buffer_size;
1645                snd_pcm_stream_unlock_irq(substream);
1646                if ((err = transfer(substream, appl_ofs, data, offset, frames)) < 0)
1647                        goto _end;
1648                snd_pcm_stream_lock_irq(substream);
1649                switch (runtime->status->state) {
1650                case SNDRV_PCM_STATE_XRUN:
1651                        err = -EPIPE;
1652                        goto _end_unlock;
1653                case SNDRV_PCM_STATE_SUSPENDED:
1654                        err = -ESTRPIPE;
1655                        goto _end_unlock;
1656                default:
1657                        break;
1658                }
1659                appl_ptr += frames;
1660                if (appl_ptr >= runtime->boundary)
1661                        appl_ptr -= runtime->boundary;
1662                runtime->control->appl_ptr = appl_ptr;
1663                if (substream->ops->ack)
1664                        substream->ops->ack(substream);
1665
1666                offset += frames;
1667                size -= frames;
1668                xfer += frames;
1669                if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1670                    snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1671                        err = snd_pcm_start(substream);
1672                        if (err < 0)
1673                                goto _end_unlock;
1674                }
1675        }
1676 _end_unlock:
1677        snd_pcm_stream_unlock_irq(substream);
1678 _end:
1679        return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
1680}
1681
1682/* sanity-check for read/write methods */
1683static int pcm_sanity_check(struct snd_pcm_substream *substream)
1684{
1685        struct snd_pcm_runtime *runtime;
1686        if (PCM_RUNTIME_CHECK(substream))
1687                return -ENXIO;
1688        runtime = substream->runtime;
1689        if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
1690                return -EINVAL;
1691        if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1692                return -EBADFD;
1693        return 0;
1694}
1695
1696snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
1697{
1698        struct snd_pcm_runtime *runtime;
1699        int nonblock;
1700        int err;
1701
1702        err = pcm_sanity_check(substream);
1703        if (err < 0)
1704                return err;
1705        runtime = substream->runtime;
1706        nonblock = !!(substream->f_flags & O_NONBLOCK);
1707
1708        if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
1709            runtime->channels > 1)
1710                return -EINVAL;
1711        return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
1712                                  snd_pcm_lib_write_transfer);
1713}
1714
1715EXPORT_SYMBOL(snd_pcm_lib_write);
1716
1717static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
1718                                       unsigned int hwoff,
1719                                       unsigned long data, unsigned int off,
1720                                       snd_pcm_uframes_t frames)
1721{
1722        struct snd_pcm_runtime *runtime = substream->runtime;
1723        int err;
1724        void __user **bufs = (void __user **)data;
1725        int channels = runtime->channels;
1726        int c;
1727        if (substream->ops->copy) {
1728                if (snd_BUG_ON(!substream->ops->silence))
1729                        return -EINVAL;
1730                for (c = 0; c < channels; ++c, ++bufs) {
1731                        if (*bufs == NULL) {
1732                                if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
1733                                        return err;
1734                        } else {
1735                                char __user *buf = *bufs + samples_to_bytes(runtime, off);
1736                                if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
1737                                        return err;
1738                        }
1739                }
1740        } else {
1741                /* default transfer behaviour */
1742                size_t dma_csize = runtime->dma_bytes / channels;
1743                for (c = 0; c < channels; ++c, ++bufs) {
1744                        char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
1745                        if (*bufs == NULL) {
1746                                snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
1747                        } else {
1748                                char __user *buf = *bufs + samples_to_bytes(runtime, off);
1749                                if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
1750                                        return -EFAULT;
1751                        }
1752                }
1753        }
1754        return 0;
1755}
1756 
1757snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
1758                                     void __user **bufs,
1759                                     snd_pcm_uframes_t frames)
1760{
1761        struct snd_pcm_runtime *runtime;
1762        int nonblock;
1763        int err;
1764
1765        err = pcm_sanity_check(substream);
1766        if (err < 0)
1767                return err;
1768        runtime = substream->runtime;
1769        nonblock = !!(substream->f_flags & O_NONBLOCK);
1770
1771        if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
1772                return -EINVAL;
1773        return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
1774                                  nonblock, snd_pcm_lib_writev_transfer);
1775}
1776
1777EXPORT_SYMBOL(snd_pcm_lib_writev);
1778
1779static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream, 
1780                                     unsigned int hwoff,
1781                                     unsigned long data, unsigned int off,
1782                                     snd_pcm_uframes_t frames)
1783{
1784        struct snd_pcm_runtime *runtime = substream->runtime;
1785        int err;
1786        char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1787        if (substream->ops->copy) {
1788                if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1789                        return err;
1790        } else {
1791                char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1792                if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
1793                        return -EFAULT;
1794        }
1795        return 0;
1796}
1797
1798static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
1799                                           unsigned long data,
1800                                           snd_pcm_uframes_t size,
1801                                           int nonblock,
1802                                           transfer_f transfer)
1803{
1804        struct snd_pcm_runtime *runtime = substream->runtime;
1805        snd_pcm_uframes_t xfer = 0;
1806        snd_pcm_uframes_t offset = 0;
1807        int err = 0;
1808
1809        if (size == 0)
1810                return 0;
1811
1812        snd_pcm_stream_lock_irq(substream);
1813        switch (runtime->status->state) {
1814        case SNDRV_PCM_STATE_PREPARED:
1815                if (size >= runtime->start_threshold) {
1816                        err = snd_pcm_start(substream);
1817                        if (err < 0)
1818                                goto _end_unlock;
1819                }
1820                break;
1821        case SNDRV_PCM_STATE_DRAINING:
1822        case SNDRV_PCM_STATE_RUNNING:
1823        case SNDRV_PCM_STATE_PAUSED:
1824                break;
1825        case SNDRV_PCM_STATE_XRUN:
1826                err = -EPIPE;
1827                goto _end_unlock;
1828        case SNDRV_PCM_STATE_SUSPENDED:
1829                err = -ESTRPIPE;
1830                goto _end_unlock;
1831        default:
1832                err = -EBADFD;
1833                goto _end_unlock;
1834        }
1835
1836        while (size > 0) {
1837                snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1838                snd_pcm_uframes_t avail;
1839                snd_pcm_uframes_t cont;
1840                if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1841                        snd_pcm_update_hw_ptr(substream);
1842                avail = snd_pcm_capture_avail(runtime);
1843                if (!avail) {
1844                        if (runtime->status->state ==
1845                            SNDRV_PCM_STATE_DRAINING) {
1846                                snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
1847                                goto _end_unlock;
1848                        }
1849                        if (nonblock) {
1850                                err = -EAGAIN;
1851                                goto _end_unlock;
1852                        }
1853                        err = wait_for_avail_min(substream, &avail);
1854                        if (err < 0)
1855                                goto _end_unlock;
1856                        if (!avail)
1857                                continue; /* draining */
1858                }
1859                frames = size > avail ? avail : size;
1860                cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1861                if (frames > cont)
1862                        frames = cont;
1863                if (snd_BUG_ON(!frames)) {
1864                        snd_pcm_stream_unlock_irq(substream);
1865                        return -EINVAL;
1866                }
1867                appl_ptr = runtime->control->appl_ptr;
1868                appl_ofs = appl_ptr % runtime->buffer_size;
1869                snd_pcm_stream_unlock_irq(substream);
1870                if ((err = transfer(substream, appl_ofs, data, offset, frames)) < 0)
1871                        goto _end;
1872                snd_pcm_stream_lock_irq(substream);
1873                switch (runtime->status->state) {
1874                case SNDRV_PCM_STATE_XRUN:
1875                        err = -EPIPE;
1876                        goto _end_unlock;
1877                case SNDRV_PCM_STATE_SUSPENDED:
1878                        err = -ESTRPIPE;
1879                        goto _end_unlock;
1880                default:
1881                        break;
1882                }
1883                appl_ptr += frames;
1884                if (appl_ptr >= runtime->boundary)
1885                        appl_ptr -= runtime->boundary;
1886                runtime->control->appl_ptr = appl_ptr;
1887                if (substream->ops->ack)
1888                        substream->ops->ack(substream);
1889
1890                offset += frames;
1891                size -= frames;
1892                xfer += frames;
1893        }
1894 _end_unlock:
1895        snd_pcm_stream_unlock_irq(substream);
1896 _end:
1897        return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
1898}
1899
1900snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
1901{
1902        struct snd_pcm_runtime *runtime;
1903        int nonblock;
1904        int err;
1905        
1906        err = pcm_sanity_check(substream);
1907        if (err < 0)
1908                return err;
1909        runtime = substream->runtime;
1910        nonblock = !!(substream->f_flags & O_NONBLOCK);
1911        if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
1912                return -EINVAL;
1913        return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
1914}
1915
1916EXPORT_SYMBOL(snd_pcm_lib_read);
1917
1918static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
1919                                      unsigned int hwoff,
1920                                      unsigned long data, unsigned int off,
1921                                      snd_pcm_uframes_t frames)
1922{
1923        struct snd_pcm_runtime *runtime = substream->runtime;
1924        int err;
1925        void __user **bufs = (void __user **)data;
1926        int channels = runtime->channels;
1927        int c;
1928        if (substream->ops->copy) {
1929                for (c = 0; c < channels; ++c, ++bufs) {
1930                        char __user *buf;
1931                        if (*bufs == NULL)
1932                                continue;
1933                        buf = *bufs + samples_to_bytes(runtime, off);
1934                        if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
1935                                return err;
1936                }
1937        } else {
1938                snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
1939                for (c = 0; c < channels; ++c, ++bufs) {
1940                        char *hwbuf;
1941                        char __user *buf;
1942                        if (*bufs == NULL)
1943                                continue;
1944
1945                        hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
1946                        buf = *bufs + samples_to_bytes(runtime, off);
1947                        if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
1948                                return -EFAULT;
1949                }
1950        }
1951        return 0;
1952}
1953 
1954snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
1955                                    void __user **bufs,
1956                                    snd_pcm_uframes_t frames)
1957{
1958        struct snd_pcm_runtime *runtime;
1959        int nonblock;
1960        int err;
1961
1962        err = pcm_sanity_check(substream);
1963        if (err < 0)
1964                return err;
1965        runtime = substream->runtime;
1966        if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1967                return -EBADFD;
1968
1969        nonblock = !!(substream->f_flags & O_NONBLOCK);
1970        if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
1971                return -EINVAL;
1972        return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
1973}
1974
1975EXPORT_SYMBOL(snd_pcm_lib_readv);
1976