sound/core/pcm_lib.c

   1 /*
   2  *  Digital Audio (PCM) abstract layer
   3  *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
   4  *                   Abramo Bagnara <abramo@alsa-project.org>
   5  *
   6  *
   7  *   This program is free software; you can redistribute it and/or modify
   8  *   it under the terms of the GNU General Public License as published by
   9  *   the Free Software Foundation; either version 2 of the License, or
  10  *   (at your option) any later version.
  11  *
  12  *   This program is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with this program; if not, write to the Free Software
  19  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  20  *
  21  */
  22
  23 #include <sound/driver.h>
  24 #include <linux/slab.h>
  25 #include <linux/time.h>
  26 #include <sound/core.h>
  27 #include <sound/control.h>
  28 #include <sound/info.h>
  29 #include <sound/pcm.h>
  30 #include <sound/pcm_params.h>
  31 #include <sound/timer.h>
  32
  33 /*
  34  * fill ring buffer with silence
  35  * runtime->silence_start: starting pointer to silence area
  36  * runtime->silence_filled: size filled with silence
  37  * runtime->silence_threshold: threshold from application
  38  * runtime->silence_size: maximal size from application
  39  *
  40  * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
  41  */
  42 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
  43 {
  44         struct snd_pcm_runtime *runtime = substream->runtime;
  45         snd_pcm_uframes_t frames, ofs, transfer;
  46
  47         if (runtime->silence_size < runtime->boundary) {
  48                 snd_pcm_sframes_t noise_dist, n;
  49                 if (runtime->silence_start != runtime->control->appl_ptr) {
  50                         n = runtime->control->appl_ptr - runtime->silence_start;
  51                         if (n < 0)
  52                                 n += runtime->boundary;
  53                         if ((snd_pcm_uframes_t)n < runtime->silence_filled)
  54                                 runtime->silence_filled -= n;
  55                         else
  56                                 runtime->silence_filled = 0;
  57                         runtime->silence_start = runtime->control->appl_ptr;
  58                 }
  59                 if (runtime->silence_filled >= runtime->buffer_size)
  60                         return;
  61                 noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
  62                 if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
  63                         return;
  64                 frames = runtime->silence_threshold - noise_dist;
  65                 if (frames > runtime->silence_size)
  66                         frames = runtime->silence_size;
  67         } else {
  68                 if (new_hw_ptr == ULONG_MAX) {  /* initialization */
  69                         snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
  70                         runtime->silence_filled = avail > 0 ? avail : 0;
  71                         runtime->silence_start = (runtime->status->hw_ptr +
  72                                                   runtime->silence_filled) %
  73                                                  runtime->boundary;
  74                 } else {
  75                         ofs = runtime->status->hw_ptr;
  76                         frames = new_hw_ptr - ofs;
  77                         if ((snd_pcm_sframes_t)frames < 0)
  78                                 frames += runtime->boundary;
  79                         runtime->silence_filled -= frames;
  80                         if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
  81                                 runtime->silence_filled = 0;
  82                                 runtime->silence_start = new_hw_ptr;
  83                         } else {
  84                                 runtime->silence_start = ofs;
  85                         }
  86                 }
  87                 frames = runtime->buffer_size - runtime->silence_filled;
  88         }
  89         snd_assert(frames <= runtime->buffer_size, 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_assert(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_assert(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
 128 static 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
 143 static 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         pos = substream->ops->pointer(substream);
 149         if (pos == SNDRV_PCM_POS_XRUN)
 150                 return pos; /* XRUN */
 151         if (runtime->tstamp_mode & SNDRV_PCM_TSTAMP_MMAP)
 152                 getnstimeofday((struct timespec *)&runtime->status->tstamp);
 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
 162 static 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
 185 static 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 */
 232 int 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  */
 281 void 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
 290 EXPORT_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  */
 298 void 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
 308 EXPORT_SYMBOL(snd_pcm_set_sync);
 309
 310 /*
 311  *  Standard ioctl routine
 312  */
 313
 314 static 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
 325 static 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
 332 static 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
 344 static 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
 353 static 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_assert(n > 0, );
 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  */
 381 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
 382 {
 383         int changed = 0;
 384         snd_assert(!snd_interval_empty(i), return -EINVAL);
 385         if (i->min < v->min) {
 386                 i->min = v->min;
 387                 i->openmin = v->openmin;
 388                 changed = 1;
 389         } else if (i->min == v->min && !i->openmin && v->openmin) {
 390                 i->openmin = 1;
 391                 changed = 1;
 392         }
 393         if (i->max > v->max) {
 394                 i->max = v->max;
 395                 i->openmax = v->openmax;
 396                 changed = 1;
 397         } else if (i->max == v->max && !i->openmax && v->openmax) {
 398                 i->openmax = 1;
 399                 changed = 1;
 400         }
 401         if (!i->integer && v->integer) {
 402                 i->integer = 1;
 403                 changed = 1;
 404         }
 405         if (i->integer) {
 406                 if (i->openmin) {
 407                         i->min++;
 408                         i->openmin = 0;
 409                 }
 410                 if (i->openmax) {
 411                         i->max--;
 412                         i->openmax = 0;
 413                 }
 414         } else if (!i->openmin && !i->openmax && i->min == i->max)
 415                 i->integer = 1;
 416         if (snd_interval_checkempty(i)) {
 417                 snd_interval_none(i);
 418                 return -EINVAL;
 419         }
 420         return changed;
 421 }
 422
 423 EXPORT_SYMBOL(snd_interval_refine);
 424
 425 static int snd_interval_refine_first(struct snd_interval *i)
 426 {
 427         snd_assert(!snd_interval_empty(i), return -EINVAL);
 428         if (snd_interval_single(i))
 429                 return 0;
 430         i->max = i->min;
 431         i->openmax = i->openmin;
 432         if (i->openmax)
 433                 i->max++;
 434         return 1;
 435 }
 436
 437 static int snd_interval_refine_last(struct snd_interval *i)
 438 {
 439         snd_assert(!snd_interval_empty(i), return -EINVAL);
 440         if (snd_interval_single(i))
 441                 return 0;
 442         i->min = i->max;
 443         i->openmin = i->openmax;
 444         if (i->openmin)
 445                 i->min--;
 446         return 1;
 447 }
 448
 449 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 450 {
 451         if (a->empty || b->empty) {
 452                 snd_interval_none(c);
 453                 return;
 454         }
 455         c->empty = 0;
 456         c->min = mul(a->min, b->min);
 457         c->openmin = (a->openmin || b->openmin);
 458         c->max = mul(a->max,  b->max);
 459         c->openmax = (a->openmax || b->openmax);
 460         c->integer = (a->integer && b->integer);
 461 }
 462
 463 /**
 464  * snd_interval_div - refine the interval value with division
 465  * @a: dividend
 466  * @b: divisor
 467  * @c: quotient
 468  *
 469  * c = a / b
 470  *
 471  * Returns non-zero if the value is changed, zero if not changed.
 472  */
 473 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 474 {
 475         unsigned int r;
 476         if (a->empty || b->empty) {
 477                 snd_interval_none(c);
 478                 return;
 479         }
 480         c->empty = 0;
 481         c->min = div32(a->min, b->max, &r);
 482         c->openmin = (r || a->openmin || b->openmax);
 483         if (b->min > 0) {
 484                 c->max = div32(a->max, b->min, &r);
 485                 if (r) {
 486                         c->max++;
 487                         c->openmax = 1;
 488                 } else
 489                         c->openmax = (a->openmax || b->openmin);
 490         } else {
 491                 c->max = UINT_MAX;
 492                 c->openmax = 0;
 493         }
 494         c->integer = 0;
 495 }
 496
 497 /**
 498  * snd_interval_muldivk - refine the interval value
 499  * @a: dividend 1
 500  * @b: dividend 2
 501  * @k: divisor (as integer)
 502  * @c: result
 503   *
 504  * c = a * b / k
 505  *
 506  * Returns non-zero if the value is changed, zero if not changed.
 507  */
 508 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
 509                       unsigned int k, struct snd_interval *c)
 510 {
 511         unsigned int r;
 512         if (a->empty || b->empty) {
 513                 snd_interval_none(c);
 514                 return;
 515         }
 516         c->empty = 0;
 517         c->min = muldiv32(a->min, b->min, k, &r);
 518         c->openmin = (r || a->openmin || b->openmin);
 519         c->max = muldiv32(a->max, b->max, k, &r);
 520         if (r) {
 521                 c->max++;
 522                 c->openmax = 1;
 523         } else
 524                 c->openmax = (a->openmax || b->openmax);
 525         c->integer = 0;
 526 }
 527
 528 /**
 529  * snd_interval_mulkdiv - refine the interval value
 530  * @a: dividend 1
 531  * @k: dividend 2 (as integer)
 532  * @b: divisor
 533  * @c: result
 534  *
 535  * c = a * k / b
 536  *
 537  * Returns non-zero if the value is changed, zero if not changed.
 538  */
 539 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
 540                       const struct snd_interval *b, struct snd_interval *c)
 541 {
 542         unsigned int r;
 543         if (a->empty || b->empty) {
 544                 snd_interval_none(c);
 545                 return;
 546         }
 547         c->empty = 0;
 548         c->min = muldiv32(a->min, k, b->max, &r);
 549         c->openmin = (r || a->openmin || b->openmax);
 550         if (b->min > 0) {
 551                 c->max = muldiv32(a->max, k, b->min, &r);
 552                 if (r) {
 553                         c->max++;
 554                         c->openmax = 1;
 555                 } else
 556                         c->openmax = (a->openmax || b->openmin);
 557         } else {
 558                 c->max = UINT_MAX;
 559                 c->openmax = 0;
 560         }
 561         c->integer = 0;
 562 }
 563
 564 /* ---- */
 565
 566
 567 /**
 568  * snd_interval_ratnum - refine the interval value
 569  * @i: interval to refine
 570  * @rats_count: number of ratnum_t
 571  * @rats: ratnum_t array
 572  * @nump: pointer to store the resultant numerator
 573  * @denp: pointer to store the resultant denominator
 574  *
 575  * Returns non-zero if the value is changed, zero if not changed.
 576  */
 577 int snd_interval_ratnum(struct snd_interval *i,
 578                         unsigned int rats_count, struct snd_ratnum *rats,
 579                         unsigned int *nump, unsigned int *denp)
 580 {
 581         unsigned int best_num, best_diff, best_den;
 582         unsigned int k;
 583         struct snd_interval t;
 584         int err;
 585
 586         best_num = best_den = best_diff = 0;
 587         for (k = 0; k < rats_count; ++k) {
 588                 unsigned int num = rats[k].num;
 589                 unsigned int den;
 590                 unsigned int q = i->min;
 591                 int diff;
 592                 if (q == 0)
 593                         q = 1;
 594                 den = div_down(num, q);
 595                 if (den < rats[k].den_min)
 596                         continue;
 597                 if (den > rats[k].den_max)
 598                         den = rats[k].den_max;
 599                 else {
 600                         unsigned int r;
 601                         r = (den - rats[k].den_min) % rats[k].den_step;
 602                         if (r != 0)
 603                                 den -= r;
 604                 }
 605                 diff = num - q * den;
 606                 if (best_num == 0 ||
 607                     diff * best_den < best_diff * den) {
 608                         best_diff = diff;
 609                         best_den = den;
 610                         best_num = num;
 611                 }
 612         }
 613         if (best_den == 0) {
 614                 i->empty = 1;
 615                 return -EINVAL;
 616         }
 617         t.min = div_down(best_num, best_den);
 618         t.openmin = !!(best_num % best_den);
 619
 620         best_num = best_den = best_diff = 0;
 621         for (k = 0; k < rats_count; ++k) {
 622                 unsigned int num = rats[k].num;
 623                 unsigned int den;
 624                 unsigned int q = i->max;
 625                 int diff;
 626                 if (q == 0) {
 627                         i->empty = 1;
 628                         return -EINVAL;
 629                 }
 630                 den = div_up(num, q);
 631                 if (den > rats[k].den_max)
 632                         continue;
 633                 if (den < rats[k].den_min)
 634                         den = rats[k].den_min;
 635                 else {
 636                         unsigned int r;
 637                         r = (den - rats[k].den_min) % rats[k].den_step;
 638                         if (r != 0)
 639                                 den += rats[k].den_step - r;
 640                 }
 641                 diff = q * den - num;
 642                 if (best_num == 0 ||
 643                     diff * best_den < best_diff * den) {
 644                         best_diff = diff;
 645                         best_den = den;
 646                         best_num = num;
 647                 }
 648         }
 649         if (best_den == 0) {
 650                 i->empty = 1;
 651                 return -EINVAL;
 652         }
 653         t.max = div_up(best_num, best_den);
 654         t.openmax = !!(best_num % best_den);
 655         t.integer = 0;
 656         err = snd_interval_refine(i, &t);
 657         if (err < 0)
 658                 return err;
 659
 660         if (snd_interval_single(i)) {
 661                 if (nump)
 662                         *nump = best_num;
 663                 if (denp)
 664                         *denp = best_den;
 665         }
 666         return err;
 667 }
 668
 669 EXPORT_SYMBOL(snd_interval_ratnum);
 670
 671 /**
 672  * snd_interval_ratden - refine the interval value
 673  * @i: interval to refine
 674  * @rats_count: number of struct ratden
 675  * @rats: struct ratden array
 676  * @nump: pointer to store the resultant numerator
 677  * @denp: pointer to store the resultant denominator
 678  *
 679  * Returns non-zero if the value is changed, zero if not changed.
 680  */
 681 static int snd_interval_ratden(struct snd_interval *i,
 682                                unsigned int rats_count, struct snd_ratden *rats,
 683                                unsigned int *nump, unsigned int *denp)
 684 {
 685         unsigned int best_num, best_diff, best_den;
 686         unsigned int k;
 687         struct snd_interval t;
 688         int err;
 689
 690         best_num = best_den = best_diff = 0;
 691         for (k = 0; k < rats_count; ++k) {
 692                 unsigned int num;
 693                 unsigned int den = rats[k].den;
 694                 unsigned int q = i->min;
 695                 int diff;
 696                 num = mul(q, den);
 697                 if (num > rats[k].num_max)
 698                         continue;
 699                 if (num < rats[k].num_min)
 700                         num = rats[k].num_max;
 701                 else {
 702                         unsigned int r;
 703                         r = (num - rats[k].num_min) % rats[k].num_step;
 704                         if (r != 0)
 705                                 num += rats[k].num_step - r;
 706                 }
 707                 diff = num - q * den;
 708                 if (best_num == 0 ||
 709                     diff * best_den < best_diff * den) {
 710                         best_diff = diff;
 711                         best_den = den;
 712                         best_num = num;
 713                 }
 714         }
 715         if (best_den == 0) {
 716                 i->empty = 1;
 717                 return -EINVAL;
 718         }
 719         t.min = div_down(best_num, best_den);
 720         t.openmin = !!(best_num % best_den);
 721
 722         best_num = best_den = best_diff = 0;
 723         for (k = 0; k < rats_count; ++k) {
 724                 unsigned int num;
 725                 unsigned int den = rats[k].den;
 726                 unsigned int q = i->max;
 727                 int diff;
 728                 num = mul(q, den);
 729                 if (num < rats[k].num_min)
 730                         continue;
 731                 if (num > rats[k].num_max)
 732                         num = rats[k].num_max;
 733                 else {
 734                         unsigned int r;
 735                         r = (num - rats[k].num_min) % rats[k].num_step;
 736                         if (r != 0)
 737                                 num -= r;
 738                 }
 739                 diff = q * den - num;
 740                 if (best_num == 0 ||
 741                     diff * best_den < best_diff * den) {
 742                         best_diff = diff;
 743                         best_den = den;
 744                         best_num = num;
 745                 }
 746         }
 747         if (best_den == 0) {
 748                 i->empty = 1;
 749                 return -EINVAL;
 750         }
 751         t.max = div_up(best_num, best_den);
 752         t.openmax = !!(best_num % best_den);
 753         t.integer = 0;
 754         err = snd_interval_refine(i, &t);
 755         if (err < 0)
 756                 return err;
 757
 758         if (snd_interval_single(i)) {
 759                 if (nump)
 760                         *nump = best_num;
 761                 if (denp)
 762                         *denp = best_den;
 763         }
 764         return err;
 765 }
 766
 767 /**
 768  * snd_interval_list - refine the interval value from the list
 769  * @i: the interval value to refine
 770  * @count: the number of elements in the list
 771  * @list: the value list
 772  * @mask: the bit-mask to evaluate
 773  *
 774  * Refines the interval value from the list.
 775  * When mask is non-zero, only the elements corresponding to bit 1 are
 776  * evaluated.
 777  *
 778  * Returns non-zero if the value is changed, zero if not changed.
 779  */
 780 int snd_interval_list(struct snd_interval *i, unsigned int count, unsigned int *list, unsigned int mask)
 781 {
 782         unsigned int k;
 783         int changed = 0;
 784         for (k = 0; k < count; k++) {
 785                 if (mask && !(mask & (1 << k)))
 786                         continue;
 787                 if (i->min == list[k] && !i->openmin)
 788                         goto _l1;
 789                 if (i->min < list[k]) {
 790                         i->min = list[k];
 791                         i->openmin = 0;
 792                         changed = 1;
 793                         goto _l1;
 794                 }
 795         }
 796         i->empty = 1;
 797         return -EINVAL;
 798  _l1:
 799         for (k = count; k-- > 0;) {
 800                 if (mask && !(mask & (1 << k)))
 801                         continue;
 802                 if (i->max == list[k] && !i->openmax)
 803                         goto _l2;
 804                 if (i->max > list[k]) {
 805                         i->max = list[k];
 806                         i->openmax = 0;
 807                         changed = 1;
 808                         goto _l2;
 809                 }
 810         }
 811         i->empty = 1;
 812         return -EINVAL;
 813  _l2:
 814         if (snd_interval_checkempty(i)) {
 815                 i->empty = 1;
 816                 return -EINVAL;
 817         }
 818         return changed;
 819 }
 820
 821 EXPORT_SYMBOL(snd_interval_list);
 822
 823 static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
 824 {
 825         unsigned int n;
 826         int changed = 0;
 827         n = (i->min - min) % step;
 828         if (n != 0 || i->openmin) {
 829                 i->min += step - n;
 830                 changed = 1;
 831         }
 832         n = (i->max - min) % step;
 833         if (n != 0 || i->openmax) {
 834                 i->max -= n;
 835                 changed = 1;
 836         }
 837         if (snd_interval_checkempty(i)) {
 838                 i->empty = 1;
 839                 return -EINVAL;
 840         }
 841         return changed;
 842 }
 843
 844 /* Info constraints helpers */
 845
 846 /**
 847  * snd_pcm_hw_rule_add - add the hw-constraint rule
 848  * @runtime: the pcm runtime instance
 849  * @cond: condition bits
 850  * @var: the variable to evaluate
 851  * @func: the evaluation function
 852  * @private: the private data pointer passed to function
 853  * @dep: the dependent variables
 854  *
 855  * Returns zero if successful, or a negative error code on failure.
 856  */
 857 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
 858                         int var,
 859                         snd_pcm_hw_rule_func_t func, void *private,
 860                         int dep, ...)
 861 {
 862         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
 863         struct snd_pcm_hw_rule *c;
 864         unsigned int k;
 865         va_list args;
 866         va_start(args, dep);
 867         if (constrs->rules_num >= constrs->rules_all) {
 868                 struct snd_pcm_hw_rule *new;
 869                 unsigned int new_rules = constrs->rules_all + 16;
 870                 new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
 871                 if (!new)
 872                         return -ENOMEM;
 873                 if (constrs->rules) {
 874                         memcpy(new, constrs->rules,
 875                                constrs->rules_num * sizeof(*c));
 876                         kfree(constrs->rules);
 877                 }
 878                 constrs->rules = new;
 879                 constrs->rules_all = new_rules;
 880         }
 881         c = &constrs->rules[constrs->rules_num];
 882         c->cond = cond;
 883         c->func = func;
 884         c->var = var;
 885         c->private = private;
 886         k = 0;
 887         while (1) {
 888                 snd_assert(k < ARRAY_SIZE(c->deps), return -EINVAL);
 889                 c->deps[k++] = dep;
 890                 if (dep < 0)
 891                         break;
 892                 dep = va_arg(args, int);
 893         }
 894         constrs->rules_num++;
 895         va_end(args);
 896         return 0;
 897 }
 898
 899 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
 900
 901 /**
 902  * snd_pcm_hw_constraint_mask
 903  * @runtime: PCM runtime instance
 904  * @var: hw_params variable to apply the mask
 905  * @mask: the bitmap mask
 906  *
 907  * Apply the constraint of the given bitmap mask to a mask parameter.
 908  */
 909 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
 910                                u_int32_t mask)
 911 {
 912         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
 913         struct snd_mask *maskp = constrs_mask(constrs, var);
 914         *maskp->bits &= mask;
 915         memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
 916         if (*maskp->bits == 0)
 917                 return -EINVAL;
 918         return 0;
 919 }
 920
 921 /**
 922  * snd_pcm_hw_constraint_mask64
 923  * @runtime: PCM runtime instance
 924  * @var: hw_params variable to apply the mask
 925  * @mask: the 64bit bitmap mask
 926  *
 927  * Apply the constraint of the given bitmap mask to a mask parameter.
 928  */
 929 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
 930                                  u_int64_t mask)
 931 {
 932         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
 933         struct snd_mask *maskp = constrs_mask(constrs, var);
 934         maskp->bits[0] &= (u_int32_t)mask;
 935         maskp->bits[1] &= (u_int32_t)(mask >> 32);
 936         memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
 937         if (! maskp->bits[0] && ! maskp->bits[1])
 938                 return -EINVAL;
 939         return 0;
 940 }
 941
 942 /**
 943  * snd_pcm_hw_constraint_integer
 944  * @runtime: PCM runtime instance
 945  * @var: hw_params variable to apply the integer constraint
 946  *
 947  * Apply the constraint of integer to an interval parameter.
 948  */
 949 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
 950 {
 951         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
 952         return snd_interval_setinteger(constrs_interval(constrs, var));
 953 }
 954
 955 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
 956
 957 /**
 958  * snd_pcm_hw_constraint_minmax
 959  * @runtime: PCM runtime instance
 960  * @var: hw_params variable to apply the range
 961  * @min: the minimal value
 962  * @max: the maximal value
 963  *
 964  * Apply the min/max range constraint to an interval parameter.
 965  */
 966 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
 967                                  unsigned int min, unsigned int max)
 968 {
 969         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
 970         struct snd_interval t;
 971         t.min = min;
 972         t.max = max;
 973         t.openmin = t.openmax = 0;
 974         t.integer = 0;
 975         return snd_interval_refine(constrs_interval(constrs, var), &t);
 976 }
 977
 978 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
 979
 980 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
 981                                 struct snd_pcm_hw_rule *rule)
 982 {
 983         struct snd_pcm_hw_constraint_list *list = rule->private;
 984         return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
 985 }
 986
 987
 988 /**
 989  * snd_pcm_hw_constraint_list
 990  * @runtime: PCM runtime instance
 991  * @cond: condition bits
 992  * @var: hw_params variable to apply the list constraint
 993  * @l: list
 994  *
 995  * Apply the list of constraints to an interval parameter.
 996  */
 997 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
 998                                unsigned int cond,
 999                                snd_pcm_hw_param_t var,
1000                                struct snd_pcm_hw_constraint_list *l)
1001 {
1002         return snd_pcm_hw_rule_add(runtime, cond, var,
1003                                    snd_pcm_hw_rule_list, l,
1004                                    var, -1);
1005 }
1006
1007 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1008
1009 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1010                                    struct snd_pcm_hw_rule *rule)
1011 {
1012         struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1013         unsigned int num = 0, den = 0;
1014         int err;
1015         err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1016                                   r->nrats, r->rats, &num, &den);
1017         if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1018                 params->rate_num = num;
1019                 params->rate_den = den;
1020         }
1021         return err;
1022 }
1023
1024 /**
1025  * snd_pcm_hw_constraint_ratnums
1026  * @runtime: PCM runtime instance
1027  * @cond: condition bits
1028  * @var: hw_params variable to apply the ratnums constraint
1029  * @r: struct snd_ratnums constriants
1030  */
1031 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1032                                   unsigned int cond,
1033                                   snd_pcm_hw_param_t var,
1034                                   struct snd_pcm_hw_constraint_ratnums *r)
1035 {
1036         return snd_pcm_hw_rule_add(runtime, cond, var,
1037                                    snd_pcm_hw_rule_ratnums, r,
1038                                    var, -1);
1039 }
1040
1041 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1042
1043 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1044                                    struct snd_pcm_hw_rule *rule)
1045 {
1046         struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1047         unsigned int num = 0, den = 0;
1048         int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1049                                   r->nrats, r->rats, &num, &den);
1050         if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1051                 params->rate_num = num;
1052                 params->rate_den = den;
1053         }
1054         return err;
1055 }
1056
1057 /**
1058  * snd_pcm_hw_constraint_ratdens
1059  * @runtime: PCM runtime instance
1060  * @cond: condition bits
1061  * @var: hw_params variable to apply the ratdens constraint
1062  * @r: struct snd_ratdens constriants
1063  */
1064 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1065                                   unsigned int cond,
1066                                   snd_pcm_hw_param_t var,
1067                                   struct snd_pcm_hw_constraint_ratdens *r)
1068 {
1069         return snd_pcm_hw_rule_add(runtime, cond, var,
1070                                    snd_pcm_hw_rule_ratdens, r,
1071                                    var, -1);
1072 }
1073
1074 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1075
1076 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1077                                   struct snd_pcm_hw_rule *rule)
1078 {
1079         unsigned int l = (unsigned long) rule->private;
1080         int width = l & 0xffff;
1081         unsigned int msbits = l >> 16;
1082         struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1083         if (snd_interval_single(i) && snd_interval_value(i) == width)
1084                 params->msbits = msbits;
1085         return 0;
1086 }
1087
1088 /**
1089  * snd_pcm_hw_constraint_msbits
1090  * @runtime: PCM runtime instance
1091  * @cond: condition bits
1092  * @width: sample bits width
1093  * @msbits: msbits width
1094  */
1095 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1096                                  unsigned int cond,
1097                                  unsigned int width,
1098                                  unsigned int msbits)
1099 {
1100         unsigned long l = (msbits << 16) | width;
1101         return snd_pcm_hw_rule_add(runtime, cond, -1,
1102                                     snd_pcm_hw_rule_msbits,
1103                                     (void*) l,
1104                                     SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1105 }
1106
1107 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1108
1109 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1110                                 struct snd_pcm_hw_rule *rule)
1111 {
1112         unsigned long step = (unsigned long) rule->private;
1113         return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1114 }
1115
1116 /**
1117  * snd_pcm_hw_constraint_step
1118  * @runtime: PCM runtime instance
1119  * @cond: condition bits
1120  * @var: hw_params variable to apply the step constraint
1121  * @step: step size
1122  */
1123 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1124                                unsigned int cond,
1125                                snd_pcm_hw_param_t var,
1126                                unsigned long step)
1127 {
1128         return snd_pcm_hw_rule_add(runtime, cond, var,
1129                                    snd_pcm_hw_rule_step, (void *) step,
1130                                    var, -1);
1131 }
1132
1133 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1134
1135 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1136 {
1137         static int pow2_sizes[] = {
1138                 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1139                 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1140                 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1141                 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1142         };
1143         return snd_interval_list(hw_param_interval(params, rule->var),
1144                                  ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1145 }
1146
1147 /**
1148  * snd_pcm_hw_constraint_pow2
1149  * @runtime: PCM runtime instance
1150  * @cond: condition bits
1151  * @var: hw_params variable to apply the power-of-2 constraint
1152  */
1153 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1154                                unsigned int cond,
1155                                snd_pcm_hw_param_t var)
1156 {
1157         return snd_pcm_hw_rule_add(runtime, cond, var,
1158                                    snd_pcm_hw_rule_pow2, NULL,
1159                                    var, -1);
1160 }
1161
1162 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1163
1164 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1165                                   snd_pcm_hw_param_t var)
1166 {
1167         if (hw_is_mask(var)) {
1168                 snd_mask_any(hw_param_mask(params, var));
1169                 params->cmask |= 1 << var;
1170                 params->rmask |= 1 << var;
1171                 return;
1172         }
1173         if (hw_is_interval(var)) {
1174                 snd_interval_any(hw_param_interval(params, var));
1175                 params->cmask |= 1 << var;
1176                 params->rmask |= 1 << var;
1177                 return;
1178         }
1179         snd_BUG();
1180 }
1181
1182 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1183 {
1184         unsigned int k;
1185         memset(params, 0, sizeof(*params));
1186         for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1187                 _snd_pcm_hw_param_any(params, k);
1188         for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1189                 _snd_pcm_hw_param_any(params, k);
1190         params->info = ~0U;
1191 }
1192
1193 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1194
1195 /**
1196  * snd_pcm_hw_param_value
1197  * @params: the hw_params instance
1198  * @var: parameter to retrieve
1199  * @dir: pointer to the direction (-1,0,1) or NULL
1200  *
1201  * Return the value for field PAR if it's fixed in configuration space
1202  *  defined by PARAMS. Return -EINVAL otherwise
1203  */
1204 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1205                            snd_pcm_hw_param_t var, int *dir)
1206 {
1207         if (hw_is_mask(var)) {
1208                 const struct snd_mask *mask = hw_param_mask_c(params, var);
1209                 if (!snd_mask_single(mask))
1210                         return -EINVAL;
1211                 if (dir)
1212                         *dir = 0;
1213                 return snd_mask_value(mask);
1214         }
1215         if (hw_is_interval(var)) {
1216                 const struct snd_interval *i = hw_param_interval_c(params, var);
1217                 if (!snd_interval_single(i))
1218                         return -EINVAL;
1219                 if (dir)
1220                         *dir = i->openmin;
1221                 return snd_interval_value(i);
1222         }
1223         return -EINVAL;
1224 }
1225
1226 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1227
1228 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1229                                 snd_pcm_hw_param_t var)
1230 {
1231         if (hw_is_mask(var)) {
1232                 snd_mask_none(hw_param_mask(params, var));
1233                 params->cmask |= 1 << var;
1234                 params->rmask |= 1 << var;
1235         } else if (hw_is_interval(var)) {
1236                 snd_interval_none(hw_param_interval(params, var));
1237                 params->cmask |= 1 << var;
1238                 params->rmask |= 1 << var;
1239         } else {
1240                 snd_BUG();
1241         }
1242 }
1243
1244 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1245
1246 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1247                                    snd_pcm_hw_param_t var)
1248 {
1249         int changed;
1250         if (hw_is_mask(var))
1251                 changed = snd_mask_refine_first(hw_param_mask(params, var));
1252         else if (hw_is_interval(var))
1253                 changed = snd_interval_refine_first(hw_param_interval(params, var));
1254         else
1255                 return -EINVAL;
1256         if (changed) {
1257                 params->cmask |= 1 << var;
1258                 params->rmask |= 1 << var;
1259         }
1260         return changed;
1261 }
1262
1263
1264 /**
1265  * snd_pcm_hw_param_first
1266  * @pcm: PCM instance
1267  * @params: the hw_params instance
1268  * @var: parameter to retrieve
1269  * @dir: pointer to the direction (-1,0,1) or NULL
1270  *
1271  * Inside configuration space defined by PARAMS remove from PAR all
1272  * values > minimum. Reduce configuration space accordingly.
1273  * Return the minimum.
1274  */
1275 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1276                            struct snd_pcm_hw_params *params,
1277                            snd_pcm_hw_param_t var, int *dir)
1278 {
1279         int changed = _snd_pcm_hw_param_first(params, var);
1280         if (changed < 0)
1281                 return changed;
1282         if (params->rmask) {
1283                 int err = snd_pcm_hw_refine(pcm, params);
1284                 snd_assert(err >= 0, return err);
1285         }
1286         return snd_pcm_hw_param_value(params, var, dir);
1287 }
1288
1289 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1290
1291 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1292                                   snd_pcm_hw_param_t var)
1293 {
1294         int changed;
1295         if (hw_is_mask(var))
1296                 changed = snd_mask_refine_last(hw_param_mask(params, var));
1297         else if (hw_is_interval(var))
1298                 changed = snd_interval_refine_last(hw_param_interval(params, var));
1299         else
1300                 return -EINVAL;
1301         if (changed) {
1302                 params->cmask |= 1 << var;
1303                 params->rmask |= 1 << var;
1304         }
1305         return changed;
1306 }
1307
1308
1309 /**
1310  * snd_pcm_hw_param_last
1311  * @pcm: PCM instance
1312  * @params: the hw_params instance
1313  * @var: parameter to retrieve
1314  * @dir: pointer to the direction (-1,0,1) or NULL
1315  *
1316  * Inside configuration space defined by PARAMS remove from PAR all
1317  * values < maximum. Reduce configuration space accordingly.
1318  * Return the maximum.
1319  */
1320 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1321                           struct snd_pcm_hw_params *params,
1322                           snd_pcm_hw_param_t var, int *dir)
1323 {
1324         int changed = _snd_pcm_hw_param_last(params, var);
1325         if (changed < 0)
1326                 return changed;
1327         if (params->rmask) {
1328                 int err = snd_pcm_hw_refine(pcm, params);
1329                 snd_assert(err >= 0, return err);
1330         }
1331         return snd_pcm_hw_param_value(params, var, dir);
1332 }
1333
1334 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1335
1336 /**
1337  * snd_pcm_hw_param_choose
1338  * @pcm: PCM instance
1339  * @params: the hw_params instance
1340  *
1341  * Choose one configuration from configuration space defined by PARAMS
1342  * The configuration chosen is that obtained fixing in this order:
1343  * first access, first format, first subformat, min channels,
1344  * min rate, min period time, max buffer size, min tick time
1345  */
1346 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1347                              struct snd_pcm_hw_params *params)
1348 {
1349         static int vars[] = {
1350                 SNDRV_PCM_HW_PARAM_ACCESS,
1351                 SNDRV_PCM_HW_PARAM_FORMAT,
1352                 SNDRV_PCM_HW_PARAM_SUBFORMAT,
1353                 SNDRV_PCM_HW_PARAM_CHANNELS,
1354                 SNDRV_PCM_HW_PARAM_RATE,
1355                 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1356                 SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1357                 SNDRV_PCM_HW_PARAM_TICK_TIME,
1358                 -1
1359         };
1360         int err, *v;
1361
1362         for (v = vars; *v != -1; v++) {
1363                 if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1364                         err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1365                 else
1366                         err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1367                 snd_assert(err >= 0, return err);
1368         }
1369         return 0;
1370 }
1371
1372 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1373                                    void *arg)
1374 {
1375         struct snd_pcm_runtime *runtime = substream->runtime;
1376         unsigned long flags;
1377         snd_pcm_stream_lock_irqsave(substream, flags);
1378         if (snd_pcm_running(substream) &&
1379             snd_pcm_update_hw_ptr(substream) >= 0)
1380                 runtime->status->hw_ptr %= runtime->buffer_size;
1381         else
1382                 runtime->status->hw_ptr = 0;
1383         snd_pcm_stream_unlock_irqrestore(substream, flags);
1384         return 0;
1385 }
1386
1387 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1388                                           void *arg)
1389 {
1390         struct snd_pcm_channel_info *info = arg;
1391         struct snd_pcm_runtime *runtime = substream->runtime;
1392         int width;
1393         if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1394                 info->offset = -1;
1395                 return 0;
1396         }
1397         width = snd_pcm_format_physical_width(runtime->format);
1398         if (width < 0)
1399                 return width;
1400         info->offset = 0;
1401         switch (runtime->access) {
1402         case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1403         case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1404                 info->first = info->channel * width;
1405                 info->step = runtime->channels * width;
1406                 break;
1407         case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1408         case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1409         {
1410                 size_t size = runtime->dma_bytes / runtime->channels;
1411                 info->first = info->channel * size * 8;
1412                 info->step = width;
1413                 break;
1414         }
1415         default:
1416                 snd_BUG();
1417                 break;
1418         }
1419         return 0;
1420 }
1421
1422 /**
1423  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1424  * @substream: the pcm substream instance
1425  * @cmd: ioctl command
1426  * @arg: ioctl argument
1427  *
1428  * Processes the generic ioctl commands for PCM.
1429  * Can be passed as the ioctl callback for PCM ops.
1430  *
1431  * Returns zero if successful, or a negative error code on failure.
1432  */
1433 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1434                       unsigned int cmd, void *arg)
1435 {
1436         switch (cmd) {
1437         case SNDRV_PCM_IOCTL1_INFO:
1438                 return 0;
1439         case SNDRV_PCM_IOCTL1_RESET:
1440                 return snd_pcm_lib_ioctl_reset(substream, arg);
1441         case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1442                 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1443         }
1444         return -ENXIO;
1445 }
1446
1447 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1448
1449 /*
1450  *  Conditions
1451  */
1452
1453 static void snd_pcm_system_tick_set(struct snd_pcm_substream *substream,
1454                                     unsigned long ticks)
1455 {
1456         struct snd_pcm_runtime *runtime = substream->runtime;
1457         if (ticks == 0)
1458                 del_timer(&runtime->tick_timer);
1459         else {
1460                 ticks += (1000000 / HZ) - 1;
1461                 ticks /= (1000000 / HZ);
1462                 mod_timer(&runtime->tick_timer, jiffies + ticks);
1463         }
1464 }
1465
1466 /* Temporary alias */
1467 void snd_pcm_tick_set(struct snd_pcm_substream *substream, unsigned long ticks)
1468 {
1469         snd_pcm_system_tick_set(substream, ticks);
1470 }
1471
1472 void snd_pcm_tick_prepare(struct snd_pcm_substream *substream)
1473 {
1474         struct snd_pcm_runtime *runtime = substream->runtime;
1475         snd_pcm_uframes_t frames = ULONG_MAX;
1476         snd_pcm_uframes_t avail, dist;
1477         unsigned int ticks;
1478         u_int64_t n;
1479         u_int32_t r;
1480         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
1481                 if (runtime->silence_size >= runtime->boundary) {
1482                         frames = 1;
1483                 } else if (runtime->silence_size > 0 &&
1484                            runtime->silence_filled < runtime->buffer_size) {
1485                         snd_pcm_sframes_t noise_dist;
1486                         noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
1487                         if (noise_dist > (snd_pcm_sframes_t)runtime->silence_threshold)
1488                                 frames = noise_dist - runtime->silence_threshold;
1489                 }
1490                 avail = snd_pcm_playback_avail(runtime);
1491         } else {
1492                 avail = snd_pcm_capture_avail(runtime);
1493         }
1494         if (avail < runtime->control->avail_min) {
1495                 snd_pcm_sframes_t n = runtime->control->avail_min - avail;
1496                 if (n > 0 && frames > (snd_pcm_uframes_t)n)
1497                         frames = n;
1498         }
1499         if (avail < runtime->buffer_size) {
1500                 snd_pcm_sframes_t n = runtime->buffer_size - avail;
1501                 if (n > 0 && frames > (snd_pcm_uframes_t)n)
1502                         frames = n;
1503         }
1504         if (frames == ULONG_MAX) {
1505                 snd_pcm_tick_set(substream, 0);
1506                 return;
1507         }
1508         dist = runtime->status->hw_ptr - runtime->hw_ptr_base;
1509         /* Distance to next interrupt */
1510         dist = runtime->period_size - dist % runtime->period_size;
1511         if (dist <= frames) {
1512                 snd_pcm_tick_set(substream, 0);
1513                 return;
1514         }
1515         /* the base time is us */
1516         n = frames;
1517         n *= 1000000;
1518         div64_32(&n, runtime->tick_time * runtime->rate, &r);
1519         ticks = n + (r > 0 ? 1 : 0);
1520         if (ticks < runtime->sleep_min)
1521                 ticks = runtime->sleep_min;
1522         snd_pcm_tick_set(substream, (unsigned long) ticks);
1523 }
1524
1525 void snd_pcm_tick_elapsed(struct snd_pcm_substream *substream)
1526 {
1527         struct snd_pcm_runtime *runtime;
1528         unsigned long flags;
1529
1530         snd_assert(substream != NULL, return);
1531         runtime = substream->runtime;
1532         snd_assert(runtime != NULL, return);
1533
1534         snd_pcm_stream_lock_irqsave(substream, flags);
1535         if (!snd_pcm_running(substream) ||
1536             snd_pcm_update_hw_ptr(substream) < 0)
1537                 goto _end;
1538         if (runtime->sleep_min)
1539                 snd_pcm_tick_prepare(substream);
1540  _end:
1541         snd_pcm_stream_unlock_irqrestore(substream, flags);
1542 }
1543
1544 /**
1545  * snd_pcm_period_elapsed - update the pcm status for the next period
1546  * @substream: the pcm substream instance
1547  *
1548  * This function is called from the interrupt handler when the
1549  * PCM has processed the period size.  It will update the current
1550  * pointer, set up the tick, wake up sleepers, etc.
1551  *
1552  * Even if more than one periods have elapsed since the last call, you
1553  * have to call this only once.
1554  */
1555 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1556 {
1557         struct snd_pcm_runtime *runtime;
1558         unsigned long flags;
1559
1560         snd_assert(substream != NULL, return);
1561         runtime = substream->runtime;
1562         snd_assert(runtime != NULL, return);
1563
1564         if (runtime->transfer_ack_begin)
1565                 runtime->transfer_ack_begin(substream);
1566
1567         snd_pcm_stream_lock_irqsave(substream, flags);
1568         if (!snd_pcm_running(substream) ||
1569             snd_pcm_update_hw_ptr_interrupt(substream) < 0)
1570                 goto _end;
1571
1572         if (substream->timer_running)
1573                 snd_timer_interrupt(substream->timer, 1);
1574         if (runtime->sleep_min)
1575                 snd_pcm_tick_prepare(substream);
1576  _end:
1577         snd_pcm_stream_unlock_irqrestore(substream, flags);
1578         if (runtime->transfer_ack_end)
1579                 runtime->transfer_ack_end(substream);
1580         kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1581 }
1582
1583 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1584
1585 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1586                                       unsigned int hwoff,
1587                                       unsigned long data, unsigned int off,
1588                                       snd_pcm_uframes_t frames)
1589 {
1590         struct snd_pcm_runtime *runtime = substream->runtime;
1591         int err;
1592         char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1593         if (substream->ops->copy) {
1594                 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1595                         return err;
1596         } else {
1597                 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1598                 snd_assert(runtime->dma_area, return -EFAULT);
1599                 if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1600                         return -EFAULT;
1601         }
1602         return 0;
1603 }
1604
1605 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1606                           unsigned long data, unsigned int off,
1607                           snd_pcm_uframes_t size);
1608
1609 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1610                                             unsigned long data,
1611                                             snd_pcm_uframes_t size,
1612                                             int nonblock,
1613                                             transfer_f transfer)
1614 {
1615         struct snd_pcm_runtime *runtime = substream->runtime;
1616         snd_pcm_uframes_t xfer = 0;
1617         snd_pcm_uframes_t offset = 0;
1618         int err = 0;
1619
1620         if (size == 0)
1621                 return 0;
1622         if (size > runtime->xfer_align)
1623                 size -= size % runtime->xfer_align;
1624
1625         snd_pcm_stream_lock_irq(substream);
1626         switch (runtime->status->state) {
1627         case SNDRV_PCM_STATE_PREPARED:
1628         case SNDRV_PCM_STATE_RUNNING:
1629         case SNDRV_PCM_STATE_PAUSED:
1630                 break;
1631         case SNDRV_PCM_STATE_XRUN:
1632                 err = -EPIPE;
1633                 goto _end_unlock;
1634         case SNDRV_PCM_STATE_SUSPENDED:
1635                 err = -ESTRPIPE;
1636                 goto _end_unlock;
1637         default:
1638                 err = -EBADFD;
1639                 goto _end_unlock;
1640         }
1641
1642         while (size > 0) {
1643                 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1644                 snd_pcm_uframes_t avail;
1645                 snd_pcm_uframes_t cont;
1646                 if (runtime->sleep_min == 0 && runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1647                         snd_pcm_update_hw_ptr(substream);
1648                 avail = snd_pcm_playback_avail(runtime);
1649                 if (((avail < runtime->control->avail_min && size > avail) ||
1650                    (size >= runtime->xfer_align && avail < runtime->xfer_align))) {
1651                         wait_queue_t wait;
1652                         enum { READY, SIGNALED, ERROR, SUSPENDED, EXPIRED, DROPPED } state;
1653                         long tout;
1654
1655                         if (nonblock) {
1656                                 err = -EAGAIN;
1657                                 goto _end_unlock;
1658                         }
1659
1660                         init_waitqueue_entry(&wait, current);
1661                         add_wait_queue(&runtime->sleep, &wait);
1662                         while (1) {
1663                                 if (signal_pending(current)) {
1664                                         state = SIGNALED;
1665                                         break;
1666                                 }
1667                                 set_current_state(TASK_INTERRUPTIBLE);
1668                                 snd_pcm_stream_unlock_irq(substream);
1669                                 tout = schedule_timeout(10 * HZ);
1670                                 snd_pcm_stream_lock_irq(substream);
1671                                 if (tout == 0) {
1672                                         if (runtime->status->state != SNDRV_PCM_STATE_PREPARED &&
1673                                             runtime->status->state != SNDRV_PCM_STATE_PAUSED) {
1674                                                 state = runtime->status->state == SNDRV_PCM_STATE_SUSPENDED ? SUSPENDED : EXPIRED;
1675                                                 break;
1676                                         }
1677                                 }
1678                                 switch (runtime->status->state) {
1679                                 case SNDRV_PCM_STATE_XRUN:
1680                                 case SNDRV_PCM_STATE_DRAINING:
1681                                         state = ERROR;
1682                                         goto _end_loop;
1683                                 case SNDRV_PCM_STATE_SUSPENDED:
1684                                         state = SUSPENDED;
1685                                         goto _end_loop;
1686                                 case SNDRV_PCM_STATE_SETUP:
1687                                         state = DROPPED;
1688                                         goto _end_loop;
1689                                 default:
1690                                         break;
1691                                 }
1692                                 avail = snd_pcm_playback_avail(runtime);
1693                                 if (avail >= runtime->control->avail_min) {
1694                                         state = READY;
1695                                         break;
1696                                 }
1697                         }
1698                        _end_loop:
1699                         remove_wait_queue(&runtime->sleep, &wait);
1700
1701                         switch (state) {
1702                         case ERROR:
1703                                 err = -EPIPE;
1704                                 goto _end_unlock;
1705                         case SUSPENDED:
1706                                 err = -ESTRPIPE;
1707                                 goto _end_unlock;
1708                         case SIGNALED:
1709                                 err = -ERESTARTSYS;
1710                                 goto _end_unlock;
1711                         case EXPIRED:
1712                                 snd_printd("playback write error (DMA or IRQ trouble?)\n");
1713                                 err = -EIO;
1714                                 goto _end_unlock;
1715                         case DROPPED:
1716                                 err = -EBADFD;
1717                                 goto _end_unlock;
1718                         default:
1719                                 break;
1720                         }
1721                 }
1722                 if (avail > runtime->xfer_align)
1723                         avail -= avail % runtime->xfer_align;
1724                 frames = size > avail ? avail : size;
1725                 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1726                 if (frames > cont)
1727                         frames = cont;
1728                 snd_assert(frames != 0, snd_pcm_stream_unlock_irq(substream); return -EINVAL);
1729                 appl_ptr = runtime->control->appl_ptr;
1730                 appl_ofs = appl_ptr % runtime->buffer_size;
1731                 snd_pcm_stream_unlock_irq(substream);
1732                 if ((err = transfer(substream, appl_ofs, data, offset, frames)) < 0)
1733                         goto _end;
1734                 snd_pcm_stream_lock_irq(substream);
1735                 switch (runtime->status->state) {
1736                 case SNDRV_PCM_STATE_XRUN:
1737                         err = -EPIPE;
1738                         goto _end_unlock;
1739                 case SNDRV_PCM_STATE_SUSPENDED:
1740                         err = -ESTRPIPE;
1741                         goto _end_unlock;
1742                 default:
1743                         break;
1744                 }
1745                 appl_ptr += frames;
1746                 if (appl_ptr >= runtime->boundary)
1747                         appl_ptr -= runtime->boundary;
1748                 runtime->control->appl_ptr = appl_ptr;
1749                 if (substream->ops->ack)
1750                         substream->ops->ack(substream);
1751
1752                 offset += frames;
1753                 size -= frames;
1754                 xfer += frames;
1755                 if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1756                     snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1757                         err = snd_pcm_start(substream);
1758                         if (err < 0)
1759                                 goto _end_unlock;
1760                 }
1761                 if (runtime->sleep_min &&
1762                     runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1763                         snd_pcm_tick_prepare(substream);
1764         }
1765  _end_unlock:
1766         snd_pcm_stream_unlock_irq(substream);
1767  _end:
1768         return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
1769 }
1770
1771 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
1772 {
1773         struct snd_pcm_runtime *runtime;
1774         int nonblock;
1775
1776         snd_assert(substream != NULL, return -ENXIO);
1777         runtime = substream->runtime;
1778         snd_assert(runtime != NULL, return -ENXIO);
1779         snd_assert(substream->ops->copy != NULL || runtime->dma_area != NULL, return -EINVAL);
1780         if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1781                 return -EBADFD;
1782
1783         nonblock = !!(substream->f_flags & O_NONBLOCK);
1784
1785         if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
1786             runtime->channels > 1)
1787                 return -EINVAL;
1788         return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
1789                                   snd_pcm_lib_write_transfer);
1790 }
1791
1792 EXPORT_SYMBOL(snd_pcm_lib_write);
1793
1794 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
1795                                        unsigned int hwoff,
1796                                        unsigned long data, unsigned int off,
1797                                        snd_pcm_uframes_t frames)
1798 {
1799         struct snd_pcm_runtime *runtime = substream->runtime;
1800         int err;
1801         void __user **bufs = (void __user **)data;
1802         int channels = runtime->channels;
1803         int c;
1804         if (substream->ops->copy) {
1805                 snd_assert(substream->ops->silence != NULL, return -EINVAL);
1806                 for (c = 0; c < channels; ++c, ++bufs) {
1807                         if (*bufs == NULL) {
1808                                 if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
1809                                         return err;
1810                         } else {
1811                                 char __user *buf = *bufs + samples_to_bytes(runtime, off);
1812                                 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
1813                                         return err;
1814                         }
1815                 }
1816         } else {
1817                 /* default transfer behaviour */
1818                 size_t dma_csize = runtime->dma_bytes / channels;
1819                 snd_assert(runtime->dma_area, return -EFAULT);
1820                 for (c = 0; c < channels; ++c, ++bufs) {
1821                         char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
1822                         if (*bufs == NULL) {
1823                                 snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
1824                         } else {
1825                                 char __user *buf = *bufs + samples_to_bytes(runtime, off);
1826                                 if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
1827                                         return -EFAULT;
1828                         }
1829                 }
1830         }
1831         return 0;
1832 }
1833
1834 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
1835                                      void __user **bufs,
1836                                      snd_pcm_uframes_t frames)
1837 {
1838         struct snd_pcm_runtime *runtime;
1839         int nonblock;
1840
1841         snd_assert(substream != NULL, return -ENXIO);
1842         runtime = substream->runtime;
1843         snd_assert(runtime != NULL, return -ENXIO);
1844         snd_assert(substream->ops->copy != NULL || runtime->dma_area != NULL, return -EINVAL);
1845         if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1846                 return -EBADFD;
1847
1848         nonblock = !!(substream->f_flags & O_NONBLOCK);
1849
1850         if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
1851                 return -EINVAL;
1852         return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
1853                                   nonblock, snd_pcm_lib_writev_transfer);
1854 }
1855
1856 EXPORT_SYMBOL(snd_pcm_lib_writev);
1857
1858 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
1859                                      unsigned int hwoff,
1860                                      unsigned long data, unsigned int off,
1861                                      snd_pcm_uframes_t frames)
1862 {
1863         struct snd_pcm_runtime *runtime = substream->runtime;
1864         int err;
1865         char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1866         if (substream->ops->copy) {
1867                 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1868                         return err;
1869         } else {
1870                 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1871                 snd_assert(runtime->dma_area, return -EFAULT);
1872                 if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
1873                         return -EFAULT;
1874         }
1875         return 0;
1876 }
1877
1878 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
1879                                            unsigned long data,
1880                                            snd_pcm_uframes_t size,
1881                                            int nonblock,
1882                                            transfer_f transfer)
1883 {
1884         struct snd_pcm_runtime *runtime = substream->runtime;
1885         snd_pcm_uframes_t xfer = 0;
1886         snd_pcm_uframes_t offset = 0;
1887         int err = 0;
1888
1889         if (size == 0)
1890                 return 0;
1891         if (size > runtime->xfer_align)
1892                 size -= size % runtime->xfer_align;
1893
1894         snd_pcm_stream_lock_irq(substream);
1895         switch (runtime->status->state) {
1896         case SNDRV_PCM_STATE_PREPARED:
1897                 if (size >= runtime->start_threshold) {
1898                         err = snd_pcm_start(substream);
1899                         if (err < 0)
1900                                 goto _end_unlock;
1901                 }
1902                 break;
1903         case SNDRV_PCM_STATE_DRAINING:
1904         case SNDRV_PCM_STATE_RUNNING:
1905         case SNDRV_PCM_STATE_PAUSED:
1906                 break;
1907         case SNDRV_PCM_STATE_XRUN:
1908                 err = -EPIPE;
1909                 goto _end_unlock;
1910         case SNDRV_PCM_STATE_SUSPENDED:
1911                 err = -ESTRPIPE;
1912                 goto _end_unlock;
1913         default:
1914                 err = -EBADFD;
1915                 goto _end_unlock;
1916         }
1917
1918         while (size > 0) {
1919                 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1920                 snd_pcm_uframes_t avail;
1921                 snd_pcm_uframes_t cont;
1922                 if (runtime->sleep_min == 0 && runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1923                         snd_pcm_update_hw_ptr(substream);
1924               __draining:
1925                 avail = snd_pcm_capture_avail(runtime);
1926                 if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
1927                         if (avail < runtime->xfer_align) {
1928                                 err = -EPIPE;
1929                                 goto _end_unlock;
1930                         }
1931                 } else if ((avail < runtime->control->avail_min && size > avail) ||
1932                            (size >= runtime->xfer_align && avail < runtime->xfer_align)) {
1933                         wait_queue_t wait;
1934                         enum { READY, SIGNALED, ERROR, SUSPENDED, EXPIRED, DROPPED } state;
1935                         long tout;
1936
1937                         if (nonblock) {
1938                                 err = -EAGAIN;
1939                                 goto _end_unlock;
1940                         }
1941
1942                         init_waitqueue_entry(&wait, current);
1943                         add_wait_queue(&runtime->sleep, &wait);
1944                         while (1) {
1945                                 if (signal_pending(current)) {
1946                                         state = SIGNALED;
1947                                         break;
1948                                 }
1949                                 set_current_state(TASK_INTERRUPTIBLE);
1950                                 snd_pcm_stream_unlock_irq(substream);
1951                                 tout = schedule_timeout(10 * HZ);
1952                                 snd_pcm_stream_lock_irq(substream);
1953                                 if (tout == 0) {
1954                                         if (runtime->status->state != SNDRV_PCM_STATE_PREPARED &&
1955                                             runtime->status->state != SNDRV_PCM_STATE_PAUSED) {
1956                                                 state = runtime->status->state == SNDRV_PCM_STATE_SUSPENDED ? SUSPENDED : EXPIRED;
1957                                                 break;
1958                                         }
1959                                 }
1960                                 switch (runtime->status->state) {
1961                                 case SNDRV_PCM_STATE_XRUN:
1962                                         state = ERROR;
1963                                         goto _end_loop;
1964                                 case SNDRV_PCM_STATE_SUSPENDED:
1965                                         state = SUSPENDED;
1966                                         goto _end_loop;
1967                                 case SNDRV_PCM_STATE_DRAINING:
1968                                         goto __draining;
1969                                 case SNDRV_PCM_STATE_SETUP:
1970                                         state = DROPPED;
1971                                         goto _end_loop;
1972                                 default:
1973                                         break;
1974                                 }
1975                                 avail = snd_pcm_capture_avail(runtime);
1976                                 if (avail >= runtime->control->avail_min) {
1977                                         state = READY;
1978                                         break;
1979                                 }
1980                         }
1981                        _end_loop:
1982                         remove_wait_queue(&runtime->sleep, &wait);
1983
1984                         switch (state) {
1985                         case ERROR:
1986                                 err = -EPIPE;
1987                                 goto _end_unlock;
1988                         case SUSPENDED:
1989                                 err = -ESTRPIPE;
1990                                 goto _end_unlock;
1991                         case SIGNALED:
1992                                 err = -ERESTARTSYS;
1993                                 goto _end_unlock;
1994                         case EXPIRED:
1995                                 snd_printd("capture read error (DMA or IRQ trouble?)\n");
1996                                 err = -EIO;
1997                                 goto _end_unlock;
1998                         case DROPPED:
1999                                 err = -EBADFD;
2000                                 goto _end_unlock;
2001                         default:
2002                                 break;
2003                         }
2004                 }
2005                 if (avail > runtime->xfer_align)
2006                         avail -= avail % runtime->xfer_align;
2007                 frames = size > avail ? avail : size;
2008                 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2009                 if (frames > cont)
2010                         frames = cont;
2011                 snd_assert(frames != 0, snd_pcm_stream_unlock_irq(substream); return -EINVAL);
2012                 appl_ptr = runtime->control->appl_ptr;
2013                 appl_ofs = appl_ptr % runtime->buffer_size;
2014                 snd_pcm_stream_unlock_irq(substream);
2015                 if ((err = transfer(substream, appl_ofs, data, offset, frames)) < 0)
2016                         goto _end;
2017                 snd_pcm_stream_lock_irq(substream);
2018                 switch (runtime->status->state) {
2019                 case SNDRV_PCM_STATE_XRUN:
2020                         err = -EPIPE;
2021                         goto _end_unlock;
2022                 case SNDRV_PCM_STATE_SUSPENDED:
2023                         err = -ESTRPIPE;
2024                         goto _end_unlock;
2025                 default:
2026                         break;
2027                 }
2028                 appl_ptr += frames;
2029                 if (appl_ptr >= runtime->boundary)
2030                         appl_ptr -= runtime->boundary;
2031                 runtime->control->appl_ptr = appl_ptr;
2032                 if (substream->ops->ack)
2033                         substream->ops->ack(substream);
2034
2035                 offset += frames;
2036                 size -= frames;
2037                 xfer += frames;
2038                 if (runtime->sleep_min &&
2039                     runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2040                         snd_pcm_tick_prepare(substream);
2041         }
2042  _end_unlock:
2043         snd_pcm_stream_unlock_irq(substream);
2044  _end:
2045         return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2046 }
2047
2048 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2049 {
2050         struct snd_pcm_runtime *runtime;
2051         int nonblock;
2052
2053         snd_assert(substream != NULL, return -ENXIO);
2054         runtime = substream->runtime;
2055         snd_assert(runtime != NULL, return -ENXIO);
2056         snd_assert(substream->ops->copy != NULL || runtime->dma_area != NULL, return -EINVAL);
2057         if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2058                 return -EBADFD;
2059
2060         nonblock = !!(substream->f_flags & O_NONBLOCK);
2061         if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2062                 return -EINVAL;
2063         return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2064 }
2065
2066 EXPORT_SYMBOL(snd_pcm_lib_read);
2067
2068 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2069                                       unsigned int hwoff,
2070                                       unsigned long data, unsigned int off,
2071                                       snd_pcm_uframes_t frames)
2072 {
2073         struct snd_pcm_runtime *runtime = substream->runtime;
2074         int err;
2075         void __user **bufs = (void __user **)data;
2076         int channels = runtime->channels;
2077         int c;
2078         if (substream->ops->copy) {
2079                 for (c = 0; c < channels; ++c, ++bufs) {
2080                         char __user *buf;
2081                         if (*bufs == NULL)
2082                                 continue;
2083                         buf = *bufs + samples_to_bytes(runtime, off);
2084                         if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2085                                 return err;
2086                 }
2087         } else {
2088                 snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2089                 snd_assert(runtime->dma_area, return -EFAULT);
2090                 for (c = 0; c < channels; ++c, ++bufs) {
2091                         char *hwbuf;
2092                         char __user *buf;
2093                         if (*bufs == NULL)
2094                                 continue;
2095
2096                         hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2097                         buf = *bufs + samples_to_bytes(runtime, off);
2098                         if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2099                                 return -EFAULT;
2100                 }
2101         }
2102         return 0;
2103 }
2104
2105 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2106                                     void __user **bufs,
2107                                     snd_pcm_uframes_t frames)
2108 {
2109         struct snd_pcm_runtime *runtime;
2110         int nonblock;
2111
2112         snd_assert(substream != NULL, return -ENXIO);
2113         runtime = substream->runtime;
2114         snd_assert(runtime != NULL, return -ENXIO);
2115         snd_assert(substream->ops->copy != NULL || runtime->dma_area != NULL, return -EINVAL);
2116         if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2117                 return -EBADFD;
2118
2119         nonblock = !!(substream->f_flags & O_NONBLOCK);
2120         if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2121                 return -EINVAL;
2122         return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2123 }
2124
2125 EXPORT_SYMBOL(snd_pcm_lib_readv);