kernel/sound/core/pcm_lib.c

   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 <linux/math64.h>
  26 #include <linux/export.h>
  27 #include <sound/core.h>
  28 #include <sound/control.h>
  29 #include <sound/tlv.h>
  30 #include <sound/info.h>
  31 #include <sound/pcm.h>
  32 #include <sound/pcm_params.h>
  33 #include <sound/timer.h>
  34
  35 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
  36 #define CREATE_TRACE_POINTS
  37 #include "pcm_trace.h"
  38 #else
  39 #define trace_hwptr(substream, pos, in_interrupt)
  40 #define trace_xrun(substream)
  41 #define trace_hw_ptr_error(substream, reason)
  42 #endif
  43
  44 /*
  45  * fill ring buffer with silence
  46  * runtime->silence_start: starting pointer to silence area
  47  * runtime->silence_filled: size filled with silence
  48  * runtime->silence_threshold: threshold from application
  49  * runtime->silence_size: maximal size from application
  50  *
  51  * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
  52  */
  53 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
  54 {
  55         struct snd_pcm_runtime *runtime = substream->runtime;
  56         snd_pcm_uframes_t frames, ofs, transfer;
  57
  58         if (runtime->silence_size < runtime->boundary) {
  59                 snd_pcm_sframes_t noise_dist, n;
  60                 if (runtime->silence_start != runtime->control->appl_ptr) {
  61                         n = runtime->control->appl_ptr - runtime->silence_start;
  62                         if (n < 0)
  63                                 n += runtime->boundary;
  64                         if ((snd_pcm_uframes_t)n < runtime->silence_filled)
  65                                 runtime->silence_filled -= n;
  66                         else
  67                                 runtime->silence_filled = 0;
  68                         runtime->silence_start = runtime->control->appl_ptr;
  69                 }
  70                 if (runtime->silence_filled >= runtime->buffer_size)
  71                         return;
  72                 noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
  73                 if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
  74                         return;
  75                 frames = runtime->silence_threshold - noise_dist;
  76                 if (frames > runtime->silence_size)
  77                         frames = runtime->silence_size;
  78         } else {
  79                 if (new_hw_ptr == ULONG_MAX) {  /* initialization */
  80                         snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
  81                         if (avail > runtime->buffer_size)
  82                                 avail = runtime->buffer_size;
  83                         runtime->silence_filled = avail > 0 ? avail : 0;
  84                         runtime->silence_start = (runtime->status->hw_ptr +
  85                                                   runtime->silence_filled) %
  86                                                  runtime->boundary;
  87                 } else {
  88                         ofs = runtime->status->hw_ptr;
  89                         frames = new_hw_ptr - ofs;
  90                         if ((snd_pcm_sframes_t)frames < 0)
  91                                 frames += runtime->boundary;
  92                         runtime->silence_filled -= frames;
  93                         if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
  94                                 runtime->silence_filled = 0;
  95                                 runtime->silence_start = new_hw_ptr;
  96                         } else {
  97                                 runtime->silence_start = ofs;
  98                         }
  99                 }
 100                 frames = runtime->buffer_size - runtime->silence_filled;
 101         }
 102         if (snd_BUG_ON(frames > runtime->buffer_size))
 103                 return;
 104         if (frames == 0)
 105                 return;
 106         ofs = runtime->silence_start % runtime->buffer_size;
 107         while (frames > 0) {
 108                 transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
 109                 if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
 110                     runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
 111                         if (substream->ops->silence) {
 112                                 int err;
 113                                 err = substream->ops->silence(substream, -1, ofs, transfer);
 114                                 snd_BUG_ON(err < 0);
 115                         } else {
 116                                 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
 117                                 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
 118                         }
 119                 } else {
 120                         unsigned int c;
 121                         unsigned int channels = runtime->channels;
 122                         if (substream->ops->silence) {
 123                                 for (c = 0; c < channels; ++c) {
 124                                         int err;
 125                                         err = substream->ops->silence(substream, c, ofs, transfer);
 126                                         snd_BUG_ON(err < 0);
 127                                 }
 128                         } else {
 129                                 size_t dma_csize = runtime->dma_bytes / channels;
 130                                 for (c = 0; c < channels; ++c) {
 131                                         char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
 132                                         snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
 133                                 }
 134                         }
 135                 }
 136                 runtime->silence_filled += transfer;
 137                 frames -= transfer;
 138                 ofs = 0;
 139         }
 140 }
 141
 142 #ifdef CONFIG_SND_DEBUG
 143 void snd_pcm_debug_name(struct snd_pcm_substream *substream,
 144                            char *name, size_t len)
 145 {
 146         snprintf(name, len, "pcmC%dD%d%c:%d",
 147                  substream->pcm->card->number,
 148                  substream->pcm->device,
 149                  substream->stream ? 'c' : 'p',
 150                  substream->number);
 151 }
 152 EXPORT_SYMBOL(snd_pcm_debug_name);
 153 #endif
 154
 155 #define XRUN_DEBUG_BASIC        (1<<0)
 156 #define XRUN_DEBUG_STACK        (1<<1)  /* dump also stack */
 157 #define XRUN_DEBUG_JIFFIESCHECK (1<<2)  /* do jiffies check */
 158
 159 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 160
 161 #define xrun_debug(substream, mask) \
 162                         ((substream)->pstr->xrun_debug & (mask))
 163 #else
 164 #define xrun_debug(substream, mask)     0
 165 #endif
 166
 167 #define dump_stack_on_xrun(substream) do {                      \
 168                 if (xrun_debug(substream, XRUN_DEBUG_STACK))    \
 169                         dump_stack();                           \
 170         } while (0)
 171
 172 static void xrun(struct snd_pcm_substream *substream)
 173 {
 174         struct snd_pcm_runtime *runtime = substream->runtime;
 175
 176         trace_xrun(substream);
 177         if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
 178                 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 179         snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 180         if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
 181                 char name[16];
 182                 snd_pcm_debug_name(substream, name, sizeof(name));
 183                 pcm_warn(substream->pcm, "XRUN: %s\n", name);
 184                 dump_stack_on_xrun(substream);
 185         }
 186 }
 187
 188 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 189 #define hw_ptr_error(substream, in_interrupt, reason, fmt, args...)     \
 190         do {                                                            \
 191                 trace_hw_ptr_error(substream, reason);  \
 192                 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {          \
 193                         pr_err_ratelimited("ALSA: PCM: [%c] " reason ": " fmt, \
 194                                            (in_interrupt) ? 'Q' : 'P', ##args); \
 195                         dump_stack_on_xrun(substream);                  \
 196                 }                                                       \
 197         } while (0)
 198
 199 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
 200
 201 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
 202
 203 #endif
 204
 205 int snd_pcm_update_state(struct snd_pcm_substream *substream,
 206                          struct snd_pcm_runtime *runtime)
 207 {
 208         snd_pcm_uframes_t avail;
 209
 210         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 211                 avail = snd_pcm_playback_avail(runtime);
 212         else
 213                 avail = snd_pcm_capture_avail(runtime);
 214         if (avail > runtime->avail_max)
 215                 runtime->avail_max = avail;
 216         if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
 217                 if (avail >= runtime->buffer_size) {
 218                         snd_pcm_drain_done(substream);
 219                         return -EPIPE;
 220                 }
 221         } else {
 222                 if (avail >= runtime->stop_threshold) {
 223                         xrun(substream);
 224                         return -EPIPE;
 225                 }
 226         }
 227         if (runtime->twake) {
 228                 if (avail >= runtime->twake)
 229                         wake_up(&runtime->tsleep);
 230         } else if (avail >= runtime->control->avail_min)
 231                 wake_up(&runtime->sleep);
 232         return 0;
 233 }
 234
 235 static void update_audio_tstamp(struct snd_pcm_substream *substream,
 236                                 struct timespec *curr_tstamp,
 237                                 struct timespec *audio_tstamp)
 238 {
 239         struct snd_pcm_runtime *runtime = substream->runtime;
 240         u64 audio_frames, audio_nsecs;
 241         struct timespec driver_tstamp;
 242
 243         if (runtime->tstamp_mode != SNDRV_PCM_TSTAMP_ENABLE)
 244                 return;
 245
 246         if (!(substream->ops->get_time_info) ||
 247                 (runtime->audio_tstamp_report.actual_type ==
 248                         SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
 249
 250                 /*
 251                  * provide audio timestamp derived from pointer position
 252                  * add delay only if requested
 253                  */
 254
 255                 audio_frames = runtime->hw_ptr_wrap + runtime->status->hw_ptr;
 256
 257                 if (runtime->audio_tstamp_config.report_delay) {
 258                         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 259                                 audio_frames -=  runtime->delay;
 260                         else
 261                                 audio_frames +=  runtime->delay;
 262                 }
 263                 audio_nsecs = div_u64(audio_frames * 1000000000LL,
 264                                 runtime->rate);
 265                 *audio_tstamp = ns_to_timespec(audio_nsecs);
 266         }
 267         runtime->status->audio_tstamp = *audio_tstamp;
 268         runtime->status->tstamp = *curr_tstamp;
 269
 270         /*
 271          * re-take a driver timestamp to let apps detect if the reference tstamp
 272          * read by low-level hardware was provided with a delay
 273          */
 274         snd_pcm_gettime(substream->runtime, (struct timespec *)&driver_tstamp);
 275         runtime->driver_tstamp = driver_tstamp;
 276 }
 277
 278 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
 279                                   unsigned int in_interrupt)
 280 {
 281         struct snd_pcm_runtime *runtime = substream->runtime;
 282         snd_pcm_uframes_t pos;
 283         snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
 284         snd_pcm_sframes_t hdelta, delta;
 285         unsigned long jdelta;
 286         unsigned long curr_jiffies;
 287         struct timespec curr_tstamp;
 288         struct timespec audio_tstamp;
 289         int crossed_boundary = 0;
 290
 291         old_hw_ptr = runtime->status->hw_ptr;
 292
 293         /*
 294          * group pointer, time and jiffies reads to allow for more
 295          * accurate correlations/corrections.
 296          * The values are stored at the end of this routine after
 297          * corrections for hw_ptr position
 298          */
 299         pos = substream->ops->pointer(substream);
 300         curr_jiffies = jiffies;
 301         if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
 302                 if ((substream->ops->get_time_info) &&
 303                         (runtime->audio_tstamp_config.type_requested != SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
 304                         substream->ops->get_time_info(substream, &curr_tstamp,
 305                                                 &audio_tstamp,
 306                                                 &runtime->audio_tstamp_config,
 307                                                 &runtime->audio_tstamp_report);
 308
 309                         /* re-test in case tstamp type is not supported in hardware and was demoted to DEFAULT */
 310                         if (runtime->audio_tstamp_report.actual_type == SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)
 311                                 snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
 312                 } else
 313                         snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
 314         }
 315
 316         if (pos == SNDRV_PCM_POS_XRUN) {
 317                 xrun(substream);
 318                 return -EPIPE;
 319         }
 320         if (pos >= runtime->buffer_size) {
 321                 if (printk_ratelimit()) {
 322                         char name[16];
 323                         snd_pcm_debug_name(substream, name, sizeof(name));
 324                         pcm_err(substream->pcm,
 325                                 "BUG: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
 326                                 name, pos, runtime->buffer_size,
 327                                 runtime->period_size);
 328                 }
 329                 pos = 0;
 330         }
 331         pos -= pos % runtime->min_align;
 332         trace_hwptr(substream, pos, in_interrupt);
 333         hw_base = runtime->hw_ptr_base;
 334         new_hw_ptr = hw_base + pos;
 335         if (in_interrupt) {
 336                 /* we know that one period was processed */
 337                 /* delta = "expected next hw_ptr" for in_interrupt != 0 */
 338                 delta = runtime->hw_ptr_interrupt + runtime->period_size;
 339                 if (delta > new_hw_ptr) {
 340                         /* check for double acknowledged interrupts */
 341                         hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 342                         if (hdelta > runtime->hw_ptr_buffer_jiffies/2 + 1) {
 343                                 hw_base += runtime->buffer_size;
 344                                 if (hw_base >= runtime->boundary) {
 345                                         hw_base = 0;
 346                                         crossed_boundary++;
 347                                 }
 348                                 new_hw_ptr = hw_base + pos;
 349                                 goto __delta;
 350                         }
 351                 }
 352         }
 353         /* new_hw_ptr might be lower than old_hw_ptr in case when */
 354         /* pointer crosses the end of the ring buffer */
 355         if (new_hw_ptr < old_hw_ptr) {
 356                 hw_base += runtime->buffer_size;
 357                 if (hw_base >= runtime->boundary) {
 358                         hw_base = 0;
 359                         crossed_boundary++;
 360                 }
 361                 new_hw_ptr = hw_base + pos;
 362         }
 363       __delta:
 364         delta = new_hw_ptr - old_hw_ptr;
 365         if (delta < 0)
 366                 delta += runtime->boundary;
 367
 368         if (runtime->no_period_wakeup) {
 369                 snd_pcm_sframes_t xrun_threshold;
 370                 /*
 371                  * Without regular period interrupts, we have to check
 372                  * the elapsed time to detect xruns.
 373                  */
 374                 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 375                 if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
 376                         goto no_delta_check;
 377                 hdelta = jdelta - delta * HZ / runtime->rate;
 378                 xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
 379                 while (hdelta > xrun_threshold) {
 380                         delta += runtime->buffer_size;
 381                         hw_base += runtime->buffer_size;
 382                         if (hw_base >= runtime->boundary) {
 383                                 hw_base = 0;
 384                                 crossed_boundary++;
 385                         }
 386                         new_hw_ptr = hw_base + pos;
 387                         hdelta -= runtime->hw_ptr_buffer_jiffies;
 388                 }
 389                 goto no_delta_check;
 390         }
 391
 392         /* something must be really wrong */
 393         if (delta >= runtime->buffer_size + runtime->period_size) {
 394                 hw_ptr_error(substream, in_interrupt, "Unexpected hw_ptr",
 395                              "(stream=%i, pos=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
 396                              substream->stream, (long)pos,
 397                              (long)new_hw_ptr, (long)old_hw_ptr);
 398                 return 0;
 399         }
 400
 401         /* Do jiffies check only in xrun_debug mode */
 402         if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
 403                 goto no_jiffies_check;
 404
 405         /* Skip the jiffies check for hardwares with BATCH flag.
 406          * Such hardware usually just increases the position at each IRQ,
 407          * thus it can't give any strange position.
 408          */
 409         if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
 410                 goto no_jiffies_check;
 411         hdelta = delta;
 412         if (hdelta < runtime->delay)
 413                 goto no_jiffies_check;
 414         hdelta -= runtime->delay;
 415         jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 416         if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
 417                 delta = jdelta /
 418                         (((runtime->period_size * HZ) / runtime->rate)
 419                                                                 + HZ/100);
 420                 /* move new_hw_ptr according jiffies not pos variable */
 421                 new_hw_ptr = old_hw_ptr;
 422                 hw_base = delta;
 423                 /* use loop to avoid checks for delta overflows */
 424                 /* the delta value is small or zero in most cases */
 425                 while (delta > 0) {
 426                         new_hw_ptr += runtime->period_size;
 427                         if (new_hw_ptr >= runtime->boundary) {
 428                                 new_hw_ptr -= runtime->boundary;
 429                                 crossed_boundary--;
 430                         }
 431                         delta--;
 432                 }
 433                 /* align hw_base to buffer_size */
 434                 hw_ptr_error(substream, in_interrupt, "hw_ptr skipping",
 435                              "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
 436                              (long)pos, (long)hdelta,
 437                              (long)runtime->period_size, jdelta,
 438                              ((hdelta * HZ) / runtime->rate), hw_base,
 439                              (unsigned long)old_hw_ptr,
 440                              (unsigned long)new_hw_ptr);
 441                 /* reset values to proper state */
 442                 delta = 0;
 443                 hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
 444         }
 445  no_jiffies_check:
 446         if (delta > runtime->period_size + runtime->period_size / 2) {
 447                 hw_ptr_error(substream, in_interrupt,
 448                              "Lost interrupts?",
 449                              "(stream=%i, delta=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
 450                              substream->stream, (long)delta,
 451                              (long)new_hw_ptr,
 452                              (long)old_hw_ptr);
 453         }
 454
 455  no_delta_check:
 456         if (runtime->status->hw_ptr == new_hw_ptr) {
 457                 update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
 458                 return 0;
 459         }
 460
 461         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 462             runtime->silence_size > 0)
 463                 snd_pcm_playback_silence(substream, new_hw_ptr);
 464
 465         if (in_interrupt) {
 466                 delta = new_hw_ptr - runtime->hw_ptr_interrupt;
 467                 if (delta < 0)
 468                         delta += runtime->boundary;
 469                 delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
 470                 runtime->hw_ptr_interrupt += delta;
 471                 if (runtime->hw_ptr_interrupt >= runtime->boundary)
 472                         runtime->hw_ptr_interrupt -= runtime->boundary;
 473         }
 474         runtime->hw_ptr_base = hw_base;
 475         runtime->status->hw_ptr = new_hw_ptr;
 476         runtime->hw_ptr_jiffies = curr_jiffies;
 477         if (crossed_boundary) {
 478                 snd_BUG_ON(crossed_boundary != 1);
 479                 runtime->hw_ptr_wrap += runtime->boundary;
 480         }
 481
 482         update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
 483
 484         return snd_pcm_update_state(substream, runtime);
 485 }
 486
 487 /* CAUTION: call it with irq disabled */
 488 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
 489 {
 490         return snd_pcm_update_hw_ptr0(substream, 0);
 491 }
 492
 493 /**
 494  * snd_pcm_set_ops - set the PCM operators
 495  * @pcm: the pcm instance
 496  * @direction: stream direction, SNDRV_PCM_STREAM_XXX
 497  * @ops: the operator table
 498  *
 499  * Sets the given PCM operators to the pcm instance.
 500  */
 501 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
 502                      const struct snd_pcm_ops *ops)
 503 {
 504         struct snd_pcm_str *stream = &pcm->streams[direction];
 505         struct snd_pcm_substream *substream;
 506
 507         for (substream = stream->substream; substream != NULL; substream = substream->next)
 508                 substream->ops = ops;
 509 }
 510
 511 EXPORT_SYMBOL(snd_pcm_set_ops);
 512
 513 /**
 514  * snd_pcm_sync - set the PCM sync id
 515  * @substream: the pcm substream
 516  *
 517  * Sets the PCM sync identifier for the card.
 518  */
 519 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
 520 {
 521         struct snd_pcm_runtime *runtime = substream->runtime;
 522
 523         runtime->sync.id32[0] = substream->pcm->card->number;
 524         runtime->sync.id32[1] = -1;
 525         runtime->sync.id32[2] = -1;
 526         runtime->sync.id32[3] = -1;
 527 }
 528
 529 EXPORT_SYMBOL(snd_pcm_set_sync);
 530
 531 /*
 532  *  Standard ioctl routine
 533  */
 534
 535 static inline unsigned int div32(unsigned int a, unsigned int b,
 536                                  unsigned int *r)
 537 {
 538         if (b == 0) {
 539                 *r = 0;
 540                 return UINT_MAX;
 541         }
 542         *r = a % b;
 543         return a / b;
 544 }
 545
 546 static inline unsigned int div_down(unsigned int a, unsigned int b)
 547 {
 548         if (b == 0)
 549                 return UINT_MAX;
 550         return a / b;
 551 }
 552
 553 static inline unsigned int div_up(unsigned int a, unsigned int b)
 554 {
 555         unsigned int r;
 556         unsigned int q;
 557         if (b == 0)
 558                 return UINT_MAX;
 559         q = div32(a, b, &r);
 560         if (r)
 561                 ++q;
 562         return q;
 563 }
 564
 565 static inline unsigned int mul(unsigned int a, unsigned int b)
 566 {
 567         if (a == 0)
 568                 return 0;
 569         if (div_down(UINT_MAX, a) < b)
 570                 return UINT_MAX;
 571         return a * b;
 572 }
 573
 574 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
 575                                     unsigned int c, unsigned int *r)
 576 {
 577         u_int64_t n = (u_int64_t) a * b;
 578         if (c == 0) {
 579                 snd_BUG_ON(!n);
 580                 *r = 0;
 581                 return UINT_MAX;
 582         }
 583         n = div_u64_rem(n, c, r);
 584         if (n >= UINT_MAX) {
 585                 *r = 0;
 586                 return UINT_MAX;
 587         }
 588         return n;
 589 }
 590
 591 /**
 592  * snd_interval_refine - refine the interval value of configurator
 593  * @i: the interval value to refine
 594  * @v: the interval value to refer to
 595  *
 596  * Refines the interval value with the reference value.
 597  * The interval is changed to the range satisfying both intervals.
 598  * The interval status (min, max, integer, etc.) are evaluated.
 599  *
 600  * Return: Positive if the value is changed, zero if it's not changed, or a
 601  * negative error code.
 602  */
 603 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
 604 {
 605         int changed = 0;
 606         if (snd_BUG_ON(snd_interval_empty(i)))
 607                 return -EINVAL;
 608         if (i->min < v->min) {
 609                 i->min = v->min;
 610                 i->openmin = v->openmin;
 611                 changed = 1;
 612         } else if (i->min == v->min && !i->openmin && v->openmin) {
 613                 i->openmin = 1;
 614                 changed = 1;
 615         }
 616         if (i->max > v->max) {
 617                 i->max = v->max;
 618                 i->openmax = v->openmax;
 619                 changed = 1;
 620         } else if (i->max == v->max && !i->openmax && v->openmax) {
 621                 i->openmax = 1;
 622                 changed = 1;
 623         }
 624         if (!i->integer && v->integer) {
 625                 i->integer = 1;
 626                 changed = 1;
 627         }
 628         if (i->integer) {
 629                 if (i->openmin) {
 630                         i->min++;
 631                         i->openmin = 0;
 632                 }
 633                 if (i->openmax) {
 634                         i->max--;
 635                         i->openmax = 0;
 636                 }
 637         } else if (!i->openmin && !i->openmax && i->min == i->max)
 638                 i->integer = 1;
 639         if (snd_interval_checkempty(i)) {
 640                 snd_interval_none(i);
 641                 return -EINVAL;
 642         }
 643         return changed;
 644 }
 645
 646 EXPORT_SYMBOL(snd_interval_refine);
 647
 648 static int snd_interval_refine_first(struct snd_interval *i)
 649 {
 650         if (snd_BUG_ON(snd_interval_empty(i)))
 651                 return -EINVAL;
 652         if (snd_interval_single(i))
 653                 return 0;
 654         i->max = i->min;
 655         i->openmax = i->openmin;
 656         if (i->openmax)
 657                 i->max++;
 658         return 1;
 659 }
 660
 661 static int snd_interval_refine_last(struct snd_interval *i)
 662 {
 663         if (snd_BUG_ON(snd_interval_empty(i)))
 664                 return -EINVAL;
 665         if (snd_interval_single(i))
 666                 return 0;
 667         i->min = i->max;
 668         i->openmin = i->openmax;
 669         if (i->openmin)
 670                 i->min--;
 671         return 1;
 672 }
 673
 674 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 675 {
 676         if (a->empty || b->empty) {
 677                 snd_interval_none(c);
 678                 return;
 679         }
 680         c->empty = 0;
 681         c->min = mul(a->min, b->min);
 682         c->openmin = (a->openmin || b->openmin);
 683         c->max = mul(a->max,  b->max);
 684         c->openmax = (a->openmax || b->openmax);
 685         c->integer = (a->integer && b->integer);
 686 }
 687
 688 /**
 689  * snd_interval_div - refine the interval value with division
 690  * @a: dividend
 691  * @b: divisor
 692  * @c: quotient
 693  *
 694  * c = a / b
 695  *
 696  * Returns non-zero if the value is changed, zero if not changed.
 697  */
 698 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 699 {
 700         unsigned int r;
 701         if (a->empty || b->empty) {
 702                 snd_interval_none(c);
 703                 return;
 704         }
 705         c->empty = 0;
 706         c->min = div32(a->min, b->max, &r);
 707         c->openmin = (r || a->openmin || b->openmax);
 708         if (b->min > 0) {
 709                 c->max = div32(a->max, b->min, &r);
 710                 if (r) {
 711                         c->max++;
 712                         c->openmax = 1;
 713                 } else
 714                         c->openmax = (a->openmax || b->openmin);
 715         } else {
 716                 c->max = UINT_MAX;
 717                 c->openmax = 0;
 718         }
 719         c->integer = 0;
 720 }
 721
 722 /**
 723  * snd_interval_muldivk - refine the interval value
 724  * @a: dividend 1
 725  * @b: dividend 2
 726  * @k: divisor (as integer)
 727  * @c: result
 728   *
 729  * c = a * b / k
 730  *
 731  * Returns non-zero if the value is changed, zero if not changed.
 732  */
 733 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
 734                       unsigned int k, struct snd_interval *c)
 735 {
 736         unsigned int r;
 737         if (a->empty || b->empty) {
 738                 snd_interval_none(c);
 739                 return;
 740         }
 741         c->empty = 0;
 742         c->min = muldiv32(a->min, b->min, k, &r);
 743         c->openmin = (r || a->openmin || b->openmin);
 744         c->max = muldiv32(a->max, b->max, k, &r);
 745         if (r) {
 746                 c->max++;
 747                 c->openmax = 1;
 748         } else
 749                 c->openmax = (a->openmax || b->openmax);
 750         c->integer = 0;
 751 }
 752
 753 /**
 754  * snd_interval_mulkdiv - refine the interval value
 755  * @a: dividend 1
 756  * @k: dividend 2 (as integer)
 757  * @b: divisor
 758  * @c: result
 759  *
 760  * c = a * k / b
 761  *
 762  * Returns non-zero if the value is changed, zero if not changed.
 763  */
 764 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
 765                       const struct snd_interval *b, struct snd_interval *c)
 766 {
 767         unsigned int r;
 768         if (a->empty || b->empty) {
 769                 snd_interval_none(c);
 770                 return;
 771         }
 772         c->empty = 0;
 773         c->min = muldiv32(a->min, k, b->max, &r);
 774         c->openmin = (r || a->openmin || b->openmax);
 775         if (b->min > 0) {
 776                 c->max = muldiv32(a->max, k, b->min, &r);
 777                 if (r) {
 778                         c->max++;
 779                         c->openmax = 1;
 780                 } else
 781                         c->openmax = (a->openmax || b->openmin);
 782         } else {
 783                 c->max = UINT_MAX;
 784                 c->openmax = 0;
 785         }
 786         c->integer = 0;
 787 }
 788
 789 /* ---- */
 790
 791
 792 /**
 793  * snd_interval_ratnum - refine the interval value
 794  * @i: interval to refine
 795  * @rats_count: number of ratnum_t
 796  * @rats: ratnum_t array
 797  * @nump: pointer to store the resultant numerator
 798  * @denp: pointer to store the resultant denominator
 799  *
 800  * Return: Positive if the value is changed, zero if it's not changed, or a
 801  * negative error code.
 802  */
 803 int snd_interval_ratnum(struct snd_interval *i,
 804                         unsigned int rats_count, struct snd_ratnum *rats,
 805                         unsigned int *nump, unsigned int *denp)
 806 {
 807         unsigned int best_num, best_den;
 808         int best_diff;
 809         unsigned int k;
 810         struct snd_interval t;
 811         int err;
 812         unsigned int result_num, result_den;
 813         int result_diff;
 814
 815         best_num = best_den = best_diff = 0;
 816         for (k = 0; k < rats_count; ++k) {
 817                 unsigned int num = rats[k].num;
 818                 unsigned int den;
 819                 unsigned int q = i->min;
 820                 int diff;
 821                 if (q == 0)
 822                         q = 1;
 823                 den = div_up(num, q);
 824                 if (den < rats[k].den_min)
 825                         continue;
 826                 if (den > rats[k].den_max)
 827                         den = rats[k].den_max;
 828                 else {
 829                         unsigned int r;
 830                         r = (den - rats[k].den_min) % rats[k].den_step;
 831                         if (r != 0)
 832                                 den -= r;
 833                 }
 834                 diff = num - q * den;
 835                 if (diff < 0)
 836                         diff = -diff;
 837                 if (best_num == 0 ||
 838                     diff * best_den < best_diff * den) {
 839                         best_diff = diff;
 840                         best_den = den;
 841                         best_num = num;
 842                 }
 843         }
 844         if (best_den == 0) {
 845                 i->empty = 1;
 846                 return -EINVAL;
 847         }
 848         t.min = div_down(best_num, best_den);
 849         t.openmin = !!(best_num % best_den);
 850
 851         result_num = best_num;
 852         result_diff = best_diff;
 853         result_den = best_den;
 854         best_num = best_den = best_diff = 0;
 855         for (k = 0; k < rats_count; ++k) {
 856                 unsigned int num = rats[k].num;
 857                 unsigned int den;
 858                 unsigned int q = i->max;
 859                 int diff;
 860                 if (q == 0) {
 861                         i->empty = 1;
 862                         return -EINVAL;
 863                 }
 864                 den = div_down(num, q);
 865                 if (den > rats[k].den_max)
 866                         continue;
 867                 if (den < rats[k].den_min)
 868                         den = rats[k].den_min;
 869                 else {
 870                         unsigned int r;
 871                         r = (den - rats[k].den_min) % rats[k].den_step;
 872                         if (r != 0)
 873                                 den += rats[k].den_step - r;
 874                 }
 875                 diff = q * den - num;
 876                 if (diff < 0)
 877                         diff = -diff;
 878                 if (best_num == 0 ||
 879                     diff * best_den < best_diff * den) {
 880                         best_diff = diff;
 881                         best_den = den;
 882                         best_num = num;
 883                 }
 884         }
 885         if (best_den == 0) {
 886                 i->empty = 1;
 887                 return -EINVAL;
 888         }
 889         t.max = div_up(best_num, best_den);
 890         t.openmax = !!(best_num % best_den);
 891         t.integer = 0;
 892         err = snd_interval_refine(i, &t);
 893         if (err < 0)
 894                 return err;
 895
 896         if (snd_interval_single(i)) {
 897                 if (best_diff * result_den < result_diff * best_den) {
 898                         result_num = best_num;
 899                         result_den = best_den;
 900                 }
 901                 if (nump)
 902                         *nump = result_num;
 903                 if (denp)
 904                         *denp = result_den;
 905         }
 906         return err;
 907 }
 908
 909 EXPORT_SYMBOL(snd_interval_ratnum);
 910
 911 /**
 912  * snd_interval_ratden - refine the interval value
 913  * @i: interval to refine
 914  * @rats_count: number of struct ratden
 915  * @rats: struct ratden array
 916  * @nump: pointer to store the resultant numerator
 917  * @denp: pointer to store the resultant denominator
 918  *
 919  * Return: Positive if the value is changed, zero if it's not changed, or a
 920  * negative error code.
 921  */
 922 static int snd_interval_ratden(struct snd_interval *i,
 923                                unsigned int rats_count, struct snd_ratden *rats,
 924                                unsigned int *nump, unsigned int *denp)
 925 {
 926         unsigned int best_num, best_diff, best_den;
 927         unsigned int k;
 928         struct snd_interval t;
 929         int err;
 930
 931         best_num = best_den = best_diff = 0;
 932         for (k = 0; k < rats_count; ++k) {
 933                 unsigned int num;
 934                 unsigned int den = rats[k].den;
 935                 unsigned int q = i->min;
 936                 int diff;
 937                 num = mul(q, den);
 938                 if (num > rats[k].num_max)
 939                         continue;
 940                 if (num < rats[k].num_min)
 941                         num = rats[k].num_max;
 942                 else {
 943                         unsigned int r;
 944                         r = (num - rats[k].num_min) % rats[k].num_step;
 945                         if (r != 0)
 946                                 num += rats[k].num_step - r;
 947                 }
 948                 diff = num - q * den;
 949                 if (best_num == 0 ||
 950                     diff * best_den < best_diff * den) {
 951                         best_diff = diff;
 952                         best_den = den;
 953                         best_num = num;
 954                 }
 955         }
 956         if (best_den == 0) {
 957                 i->empty = 1;
 958                 return -EINVAL;
 959         }
 960         t.min = div_down(best_num, best_den);
 961         t.openmin = !!(best_num % best_den);
 962
 963         best_num = best_den = best_diff = 0;
 964         for (k = 0; k < rats_count; ++k) {
 965                 unsigned int num;
 966                 unsigned int den = rats[k].den;
 967                 unsigned int q = i->max;
 968                 int diff;
 969                 num = mul(q, den);
 970                 if (num < rats[k].num_min)
 971                         continue;
 972                 if (num > rats[k].num_max)
 973                         num = rats[k].num_max;
 974                 else {
 975                         unsigned int r;
 976                         r = (num - rats[k].num_min) % rats[k].num_step;
 977                         if (r != 0)
 978                                 num -= r;
 979                 }
 980                 diff = q * den - num;
 981                 if (best_num == 0 ||
 982                     diff * best_den < best_diff * den) {
 983                         best_diff = diff;
 984                         best_den = den;
 985                         best_num = num;
 986                 }
 987         }
 988         if (best_den == 0) {
 989                 i->empty = 1;
 990                 return -EINVAL;
 991         }
 992         t.max = div_up(best_num, best_den);
 993         t.openmax = !!(best_num % best_den);
 994         t.integer = 0;
 995         err = snd_interval_refine(i, &t);
 996         if (err < 0)
 997                 return err;
 998
 999         if (snd_interval_single(i)) {
1000                 if (nump)
1001                         *nump = best_num;
1002                 if (denp)
1003                         *denp = best_den;
1004         }
1005         return err;
1006 }
1007
1008 /**
1009  * snd_interval_list - refine the interval value from the list
1010  * @i: the interval value to refine
1011  * @count: the number of elements in the list
1012  * @list: the value list
1013  * @mask: the bit-mask to evaluate
1014  *
1015  * Refines the interval value from the list.
1016  * When mask is non-zero, only the elements corresponding to bit 1 are
1017  * evaluated.
1018  *
1019  * Return: Positive if the value is changed, zero if it's not changed, or a
1020  * negative error code.
1021  */
1022 int snd_interval_list(struct snd_interval *i, unsigned int count,
1023                       const unsigned int *list, unsigned int mask)
1024 {
1025         unsigned int k;
1026         struct snd_interval list_range;
1027
1028         if (!count) {
1029                 i->empty = 1;
1030                 return -EINVAL;
1031         }
1032         snd_interval_any(&list_range);
1033         list_range.min = UINT_MAX;
1034         list_range.max = 0;
1035         for (k = 0; k < count; k++) {
1036                 if (mask && !(mask & (1 << k)))
1037                         continue;
1038                 if (!snd_interval_test(i, list[k]))
1039                         continue;
1040                 list_range.min = min(list_range.min, list[k]);
1041                 list_range.max = max(list_range.max, list[k]);
1042         }
1043         return snd_interval_refine(i, &list_range);
1044 }
1045
1046 EXPORT_SYMBOL(snd_interval_list);
1047
1048 /**
1049  * snd_interval_ranges - refine the interval value from the list of ranges
1050  * @i: the interval value to refine
1051  * @count: the number of elements in the list of ranges
1052  * @ranges: the ranges list
1053  * @mask: the bit-mask to evaluate
1054  *
1055  * Refines the interval value from the list of ranges.
1056  * When mask is non-zero, only the elements corresponding to bit 1 are
1057  * evaluated.
1058  *
1059  * Return: Positive if the value is changed, zero if it's not changed, or a
1060  * negative error code.
1061  */
1062 int snd_interval_ranges(struct snd_interval *i, unsigned int count,
1063                         const struct snd_interval *ranges, unsigned int mask)
1064 {
1065         unsigned int k;
1066         struct snd_interval range_union;
1067         struct snd_interval range;
1068
1069         if (!count) {
1070                 snd_interval_none(i);
1071                 return -EINVAL;
1072         }
1073         snd_interval_any(&range_union);
1074         range_union.min = UINT_MAX;
1075         range_union.max = 0;
1076         for (k = 0; k < count; k++) {
1077                 if (mask && !(mask & (1 << k)))
1078                         continue;
1079                 snd_interval_copy(&range, &ranges[k]);
1080                 if (snd_interval_refine(&range, i) < 0)
1081                         continue;
1082                 if (snd_interval_empty(&range))
1083                         continue;
1084
1085                 if (range.min < range_union.min) {
1086                         range_union.min = range.min;
1087                         range_union.openmin = 1;
1088                 }
1089                 if (range.min == range_union.min && !range.openmin)
1090                         range_union.openmin = 0;
1091                 if (range.max > range_union.max) {
1092                         range_union.max = range.max;
1093                         range_union.openmax = 1;
1094                 }
1095                 if (range.max == range_union.max && !range.openmax)
1096                         range_union.openmax = 0;
1097         }
1098         return snd_interval_refine(i, &range_union);
1099 }
1100 EXPORT_SYMBOL(snd_interval_ranges);
1101
1102 static int snd_interval_step(struct snd_interval *i, unsigned int step)
1103 {
1104         unsigned int n;
1105         int changed = 0;
1106         n = i->min % step;
1107         if (n != 0 || i->openmin) {
1108                 i->min += step - n;
1109                 i->openmin = 0;
1110                 changed = 1;
1111         }
1112         n = i->max % step;
1113         if (n != 0 || i->openmax) {
1114                 i->max -= n;
1115                 i->openmax = 0;
1116                 changed = 1;
1117         }
1118         if (snd_interval_checkempty(i)) {
1119                 i->empty = 1;
1120                 return -EINVAL;
1121         }
1122         return changed;
1123 }
1124
1125 /* Info constraints helpers */
1126
1127 /**
1128  * snd_pcm_hw_rule_add - add the hw-constraint rule
1129  * @runtime: the pcm runtime instance
1130  * @cond: condition bits
1131  * @var: the variable to evaluate
1132  * @func: the evaluation function
1133  * @private: the private data pointer passed to function
1134  * @dep: the dependent variables
1135  *
1136  * Return: Zero if successful, or a negative error code on failure.
1137  */
1138 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1139                         int var,
1140                         snd_pcm_hw_rule_func_t func, void *private,
1141                         int dep, ...)
1142 {
1143         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1144         struct snd_pcm_hw_rule *c;
1145         unsigned int k;
1146         va_list args;
1147         va_start(args, dep);
1148         if (constrs->rules_num >= constrs->rules_all) {
1149                 struct snd_pcm_hw_rule *new;
1150                 unsigned int new_rules = constrs->rules_all + 16;
1151                 new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1152                 if (!new) {
1153                         va_end(args);
1154                         return -ENOMEM;
1155                 }
1156                 if (constrs->rules) {
1157                         memcpy(new, constrs->rules,
1158                                constrs->rules_num * sizeof(*c));
1159                         kfree(constrs->rules);
1160                 }
1161                 constrs->rules = new;
1162                 constrs->rules_all = new_rules;
1163         }
1164         c = &constrs->rules[constrs->rules_num];
1165         c->cond = cond;
1166         c->func = func;
1167         c->var = var;
1168         c->private = private;
1169         k = 0;
1170         while (1) {
1171                 if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1172                         va_end(args);
1173                         return -EINVAL;
1174                 }
1175                 c->deps[k++] = dep;
1176                 if (dep < 0)
1177                         break;
1178                 dep = va_arg(args, int);
1179         }
1180         constrs->rules_num++;
1181         va_end(args);
1182         return 0;
1183 }
1184
1185 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1186
1187 /**
1188  * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1189  * @runtime: PCM runtime instance
1190  * @var: hw_params variable to apply the mask
1191  * @mask: the bitmap mask
1192  *
1193  * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1194  *
1195  * Return: Zero if successful, or a negative error code on failure.
1196  */
1197 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1198                                u_int32_t mask)
1199 {
1200         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1201         struct snd_mask *maskp = constrs_mask(constrs, var);
1202         *maskp->bits &= mask;
1203         memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1204         if (*maskp->bits == 0)
1205                 return -EINVAL;
1206         return 0;
1207 }
1208
1209 /**
1210  * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1211  * @runtime: PCM runtime instance
1212  * @var: hw_params variable to apply the mask
1213  * @mask: the 64bit bitmap mask
1214  *
1215  * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1216  *
1217  * Return: Zero if successful, or a negative error code on failure.
1218  */
1219 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1220                                  u_int64_t mask)
1221 {
1222         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1223         struct snd_mask *maskp = constrs_mask(constrs, var);
1224         maskp->bits[0] &= (u_int32_t)mask;
1225         maskp->bits[1] &= (u_int32_t)(mask >> 32);
1226         memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1227         if (! maskp->bits[0] && ! maskp->bits[1])
1228                 return -EINVAL;
1229         return 0;
1230 }
1231 EXPORT_SYMBOL(snd_pcm_hw_constraint_mask64);
1232
1233 /**
1234  * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1235  * @runtime: PCM runtime instance
1236  * @var: hw_params variable to apply the integer constraint
1237  *
1238  * Apply the constraint of integer to an interval parameter.
1239  *
1240  * Return: Positive if the value is changed, zero if it's not changed, or a
1241  * negative error code.
1242  */
1243 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1244 {
1245         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1246         return snd_interval_setinteger(constrs_interval(constrs, var));
1247 }
1248
1249 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1250
1251 /**
1252  * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1253  * @runtime: PCM runtime instance
1254  * @var: hw_params variable to apply the range
1255  * @min: the minimal value
1256  * @max: the maximal value
1257  *
1258  * Apply the min/max range constraint to an interval parameter.
1259  *
1260  * Return: Positive if the value is changed, zero if it's not changed, or a
1261  * negative error code.
1262  */
1263 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1264                                  unsigned int min, unsigned int max)
1265 {
1266         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1267         struct snd_interval t;
1268         t.min = min;
1269         t.max = max;
1270         t.openmin = t.openmax = 0;
1271         t.integer = 0;
1272         return snd_interval_refine(constrs_interval(constrs, var), &t);
1273 }
1274
1275 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1276
1277 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1278                                 struct snd_pcm_hw_rule *rule)
1279 {
1280         struct snd_pcm_hw_constraint_list *list = rule->private;
1281         return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1282 }
1283
1284
1285 /**
1286  * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1287  * @runtime: PCM runtime instance
1288  * @cond: condition bits
1289  * @var: hw_params variable to apply the list constraint
1290  * @l: list
1291  *
1292  * Apply the list of constraints to an interval parameter.
1293  *
1294  * Return: Zero if successful, or a negative error code on failure.
1295  */
1296 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1297                                unsigned int cond,
1298                                snd_pcm_hw_param_t var,
1299                                const struct snd_pcm_hw_constraint_list *l)
1300 {
1301         return snd_pcm_hw_rule_add(runtime, cond, var,
1302                                    snd_pcm_hw_rule_list, (void *)l,
1303                                    var, -1);
1304 }
1305
1306 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1307
1308 static int snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params *params,
1309                                   struct snd_pcm_hw_rule *rule)
1310 {
1311         struct snd_pcm_hw_constraint_ranges *r = rule->private;
1312         return snd_interval_ranges(hw_param_interval(params, rule->var),
1313                                    r->count, r->ranges, r->mask);
1314 }
1315
1316
1317 /**
1318  * snd_pcm_hw_constraint_ranges - apply list of range constraints to a parameter
1319  * @runtime: PCM runtime instance
1320  * @cond: condition bits
1321  * @var: hw_params variable to apply the list of range constraints
1322  * @r: ranges
1323  *
1324  * Apply the list of range constraints to an interval parameter.
1325  *
1326  * Return: Zero if successful, or a negative error code on failure.
1327  */
1328 int snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime *runtime,
1329                                  unsigned int cond,
1330                                  snd_pcm_hw_param_t var,
1331                                  const struct snd_pcm_hw_constraint_ranges *r)
1332 {
1333         return snd_pcm_hw_rule_add(runtime, cond, var,
1334                                    snd_pcm_hw_rule_ranges, (void *)r,
1335                                    var, -1);
1336 }
1337 EXPORT_SYMBOL(snd_pcm_hw_constraint_ranges);
1338
1339 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1340                                    struct snd_pcm_hw_rule *rule)
1341 {
1342         struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1343         unsigned int num = 0, den = 0;
1344         int err;
1345         err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1346                                   r->nrats, r->rats, &num, &den);
1347         if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1348                 params->rate_num = num;
1349                 params->rate_den = den;
1350         }
1351         return err;
1352 }
1353
1354 /**
1355  * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1356  * @runtime: PCM runtime instance
1357  * @cond: condition bits
1358  * @var: hw_params variable to apply the ratnums constraint
1359  * @r: struct snd_ratnums constriants
1360  *
1361  * Return: Zero if successful, or a negative error code on failure.
1362  */
1363 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1364                                   unsigned int cond,
1365                                   snd_pcm_hw_param_t var,
1366                                   struct snd_pcm_hw_constraint_ratnums *r)
1367 {
1368         return snd_pcm_hw_rule_add(runtime, cond, var,
1369                                    snd_pcm_hw_rule_ratnums, r,
1370                                    var, -1);
1371 }
1372
1373 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1374
1375 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1376                                    struct snd_pcm_hw_rule *rule)
1377 {
1378         struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1379         unsigned int num = 0, den = 0;
1380         int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1381                                   r->nrats, r->rats, &num, &den);
1382         if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1383                 params->rate_num = num;
1384                 params->rate_den = den;
1385         }
1386         return err;
1387 }
1388
1389 /**
1390  * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1391  * @runtime: PCM runtime instance
1392  * @cond: condition bits
1393  * @var: hw_params variable to apply the ratdens constraint
1394  * @r: struct snd_ratdens constriants
1395  *
1396  * Return: Zero if successful, or a negative error code on failure.
1397  */
1398 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1399                                   unsigned int cond,
1400                                   snd_pcm_hw_param_t var,
1401                                   struct snd_pcm_hw_constraint_ratdens *r)
1402 {
1403         return snd_pcm_hw_rule_add(runtime, cond, var,
1404                                    snd_pcm_hw_rule_ratdens, r,
1405                                    var, -1);
1406 }
1407
1408 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1409
1410 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1411                                   struct snd_pcm_hw_rule *rule)
1412 {
1413         unsigned int l = (unsigned long) rule->private;
1414         int width = l & 0xffff;
1415         unsigned int msbits = l >> 16;
1416         struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1417
1418         if (!snd_interval_single(i))
1419                 return 0;
1420
1421         if ((snd_interval_value(i) == width) ||
1422             (width == 0 && snd_interval_value(i) > msbits))
1423                 params->msbits = min_not_zero(params->msbits, msbits);
1424
1425         return 0;
1426 }
1427
1428 /**
1429  * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1430  * @runtime: PCM runtime instance
1431  * @cond: condition bits
1432  * @width: sample bits width
1433  * @msbits: msbits width
1434  *
1435  * This constraint will set the number of most significant bits (msbits) if a
1436  * sample format with the specified width has been select. If width is set to 0
1437  * the msbits will be set for any sample format with a width larger than the
1438  * specified msbits.
1439  *
1440  * Return: Zero if successful, or a negative error code on failure.
1441  */
1442 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1443                                  unsigned int cond,
1444                                  unsigned int width,
1445                                  unsigned int msbits)
1446 {
1447         unsigned long l = (msbits << 16) | width;
1448         return snd_pcm_hw_rule_add(runtime, cond, -1,
1449                                     snd_pcm_hw_rule_msbits,
1450                                     (void*) l,
1451                                     SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1452 }
1453
1454 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1455
1456 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1457                                 struct snd_pcm_hw_rule *rule)
1458 {
1459         unsigned long step = (unsigned long) rule->private;
1460         return snd_interval_step(hw_param_interval(params, rule->var), step);
1461 }
1462
1463 /**
1464  * snd_pcm_hw_constraint_step - add a hw constraint step rule
1465  * @runtime: PCM runtime instance
1466  * @cond: condition bits
1467  * @var: hw_params variable to apply the step constraint
1468  * @step: step size
1469  *
1470  * Return: Zero if successful, or a negative error code on failure.
1471  */
1472 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1473                                unsigned int cond,
1474                                snd_pcm_hw_param_t var,
1475                                unsigned long step)
1476 {
1477         return snd_pcm_hw_rule_add(runtime, cond, var,
1478                                    snd_pcm_hw_rule_step, (void *) step,
1479                                    var, -1);
1480 }
1481
1482 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1483
1484 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1485 {
1486         static unsigned int pow2_sizes[] = {
1487                 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1488                 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1489                 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1490                 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1491         };
1492         return snd_interval_list(hw_param_interval(params, rule->var),
1493                                  ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1494 }
1495
1496 /**
1497  * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1498  * @runtime: PCM runtime instance
1499  * @cond: condition bits
1500  * @var: hw_params variable to apply the power-of-2 constraint
1501  *
1502  * Return: Zero if successful, or a negative error code on failure.
1503  */
1504 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1505                                unsigned int cond,
1506                                snd_pcm_hw_param_t var)
1507 {
1508         return snd_pcm_hw_rule_add(runtime, cond, var,
1509                                    snd_pcm_hw_rule_pow2, NULL,
1510                                    var, -1);
1511 }
1512
1513 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1514
1515 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1516                                            struct snd_pcm_hw_rule *rule)
1517 {
1518         unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1519         struct snd_interval *rate;
1520
1521         rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1522         return snd_interval_list(rate, 1, &base_rate, 0);
1523 }
1524
1525 /**
1526  * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1527  * @runtime: PCM runtime instance
1528  * @base_rate: the rate at which the hardware does not resample
1529  *
1530  * Return: Zero if successful, or a negative error code on failure.
1531  */
1532 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1533                                unsigned int base_rate)
1534 {
1535         return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1536                                    SNDRV_PCM_HW_PARAM_RATE,
1537                                    snd_pcm_hw_rule_noresample_func,
1538                                    (void *)(uintptr_t)base_rate,
1539                                    SNDRV_PCM_HW_PARAM_RATE, -1);
1540 }
1541 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1542
1543 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1544                                   snd_pcm_hw_param_t var)
1545 {
1546         if (hw_is_mask(var)) {
1547                 snd_mask_any(hw_param_mask(params, var));
1548                 params->cmask |= 1 << var;
1549                 params->rmask |= 1 << var;
1550                 return;
1551         }
1552         if (hw_is_interval(var)) {
1553                 snd_interval_any(hw_param_interval(params, var));
1554                 params->cmask |= 1 << var;
1555                 params->rmask |= 1 << var;
1556                 return;
1557         }
1558         snd_BUG();
1559 }
1560
1561 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1562 {
1563         unsigned int k;
1564         memset(params, 0, sizeof(*params));
1565         for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1566                 _snd_pcm_hw_param_any(params, k);
1567         for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1568                 _snd_pcm_hw_param_any(params, k);
1569         params->info = ~0U;
1570 }
1571
1572 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1573
1574 /**
1575  * snd_pcm_hw_param_value - return @params field @var value
1576  * @params: the hw_params instance
1577  * @var: parameter to retrieve
1578  * @dir: pointer to the direction (-1,0,1) or %NULL
1579  *
1580  * Return: The value for field @var if it's fixed in configuration space
1581  * defined by @params. -%EINVAL otherwise.
1582  */
1583 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1584                            snd_pcm_hw_param_t var, int *dir)
1585 {
1586         if (hw_is_mask(var)) {
1587                 const struct snd_mask *mask = hw_param_mask_c(params, var);
1588                 if (!snd_mask_single(mask))
1589                         return -EINVAL;
1590                 if (dir)
1591                         *dir = 0;
1592                 return snd_mask_value(mask);
1593         }
1594         if (hw_is_interval(var)) {
1595                 const struct snd_interval *i = hw_param_interval_c(params, var);
1596                 if (!snd_interval_single(i))
1597                         return -EINVAL;
1598                 if (dir)
1599                         *dir = i->openmin;
1600                 return snd_interval_value(i);
1601         }
1602         return -EINVAL;
1603 }
1604
1605 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1606
1607 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1608                                 snd_pcm_hw_param_t var)
1609 {
1610         if (hw_is_mask(var)) {
1611                 snd_mask_none(hw_param_mask(params, var));
1612                 params->cmask |= 1 << var;
1613                 params->rmask |= 1 << var;
1614         } else if (hw_is_interval(var)) {
1615                 snd_interval_none(hw_param_interval(params, var));
1616                 params->cmask |= 1 << var;
1617                 params->rmask |= 1 << var;
1618         } else {
1619                 snd_BUG();
1620         }
1621 }
1622
1623 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1624
1625 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1626                                    snd_pcm_hw_param_t var)
1627 {
1628         int changed;
1629         if (hw_is_mask(var))
1630                 changed = snd_mask_refine_first(hw_param_mask(params, var));
1631         else if (hw_is_interval(var))
1632                 changed = snd_interval_refine_first(hw_param_interval(params, var));
1633         else
1634                 return -EINVAL;
1635         if (changed) {
1636                 params->cmask |= 1 << var;
1637                 params->rmask |= 1 << var;
1638         }
1639         return changed;
1640 }
1641
1642
1643 /**
1644  * snd_pcm_hw_param_first - refine config space and return minimum value
1645  * @pcm: PCM instance
1646  * @params: the hw_params instance
1647  * @var: parameter to retrieve
1648  * @dir: pointer to the direction (-1,0,1) or %NULL
1649  *
1650  * Inside configuration space defined by @params remove from @var all
1651  * values > minimum. Reduce configuration space accordingly.
1652  *
1653  * Return: The minimum, or a negative error code on failure.
1654  */
1655 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1656                            struct snd_pcm_hw_params *params,
1657                            snd_pcm_hw_param_t var, int *dir)
1658 {
1659         int changed = _snd_pcm_hw_param_first(params, var);
1660         if (changed < 0)
1661                 return changed;
1662         if (params->rmask) {
1663                 int err = snd_pcm_hw_refine(pcm, params);
1664                 if (snd_BUG_ON(err < 0))
1665                         return err;
1666         }
1667         return snd_pcm_hw_param_value(params, var, dir);
1668 }
1669
1670 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1671
1672 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1673                                   snd_pcm_hw_param_t var)
1674 {
1675         int changed;
1676         if (hw_is_mask(var))
1677                 changed = snd_mask_refine_last(hw_param_mask(params, var));
1678         else if (hw_is_interval(var))
1679                 changed = snd_interval_refine_last(hw_param_interval(params, var));
1680         else
1681                 return -EINVAL;
1682         if (changed) {
1683                 params->cmask |= 1 << var;
1684                 params->rmask |= 1 << var;
1685         }
1686         return changed;
1687 }
1688
1689
1690 /**
1691  * snd_pcm_hw_param_last - refine config space and return maximum value
1692  * @pcm: PCM instance
1693  * @params: the hw_params instance
1694  * @var: parameter to retrieve
1695  * @dir: pointer to the direction (-1,0,1) or %NULL
1696  *
1697  * Inside configuration space defined by @params remove from @var all
1698  * values < maximum. Reduce configuration space accordingly.
1699  *
1700  * Return: The maximum, or a negative error code on failure.
1701  */
1702 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1703                           struct snd_pcm_hw_params *params,
1704                           snd_pcm_hw_param_t var, int *dir)
1705 {
1706         int changed = _snd_pcm_hw_param_last(params, var);
1707         if (changed < 0)
1708                 return changed;
1709         if (params->rmask) {
1710                 int err = snd_pcm_hw_refine(pcm, params);
1711                 if (snd_BUG_ON(err < 0))
1712                         return err;
1713         }
1714         return snd_pcm_hw_param_value(params, var, dir);
1715 }
1716
1717 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1718
1719 /**
1720  * snd_pcm_hw_param_choose - choose a configuration defined by @params
1721  * @pcm: PCM instance
1722  * @params: the hw_params instance
1723  *
1724  * Choose one configuration from configuration space defined by @params.
1725  * The configuration chosen is that obtained fixing in this order:
1726  * first access, first format, first subformat, min channels,
1727  * min rate, min period time, max buffer size, min tick time
1728  *
1729  * Return: Zero if successful, or a negative error code on failure.
1730  */
1731 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1732                              struct snd_pcm_hw_params *params)
1733 {
1734         static int vars[] = {
1735                 SNDRV_PCM_HW_PARAM_ACCESS,
1736                 SNDRV_PCM_HW_PARAM_FORMAT,
1737                 SNDRV_PCM_HW_PARAM_SUBFORMAT,
1738                 SNDRV_PCM_HW_PARAM_CHANNELS,
1739                 SNDRV_PCM_HW_PARAM_RATE,
1740                 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1741                 SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1742                 SNDRV_PCM_HW_PARAM_TICK_TIME,
1743                 -1
1744         };
1745         int err, *v;
1746
1747         for (v = vars; *v != -1; v++) {
1748                 if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1749                         err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1750                 else
1751                         err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1752                 if (snd_BUG_ON(err < 0))
1753                         return err;
1754         }
1755         return 0;
1756 }
1757
1758 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1759                                    void *arg)
1760 {
1761         struct snd_pcm_runtime *runtime = substream->runtime;
1762         unsigned long flags;
1763         snd_pcm_stream_lock_irqsave(substream, flags);
1764         if (snd_pcm_running(substream) &&
1765             snd_pcm_update_hw_ptr(substream) >= 0)
1766                 runtime->status->hw_ptr %= runtime->buffer_size;
1767         else {
1768                 runtime->status->hw_ptr = 0;
1769                 runtime->hw_ptr_wrap = 0;
1770         }
1771         snd_pcm_stream_unlock_irqrestore(substream, flags);
1772         return 0;
1773 }
1774
1775 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1776                                           void *arg)
1777 {
1778         struct snd_pcm_channel_info *info = arg;
1779         struct snd_pcm_runtime *runtime = substream->runtime;
1780         int width;
1781         if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1782                 info->offset = -1;
1783                 return 0;
1784         }
1785         width = snd_pcm_format_physical_width(runtime->format);
1786         if (width < 0)
1787                 return width;
1788         info->offset = 0;
1789         switch (runtime->access) {
1790         case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1791         case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1792                 info->first = info->channel * width;
1793                 info->step = runtime->channels * width;
1794                 break;
1795         case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1796         case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1797         {
1798                 size_t size = runtime->dma_bytes / runtime->channels;
1799                 info->first = info->channel * size * 8;
1800                 info->step = width;
1801                 break;
1802         }
1803         default:
1804                 snd_BUG();
1805                 break;
1806         }
1807         return 0;
1808 }
1809
1810 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1811                                        void *arg)
1812 {
1813         struct snd_pcm_hw_params *params = arg;
1814         snd_pcm_format_t format;
1815         int channels;
1816         ssize_t frame_size;
1817
1818         params->fifo_size = substream->runtime->hw.fifo_size;
1819         if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1820                 format = params_format(params);
1821                 channels = params_channels(params);
1822                 frame_size = snd_pcm_format_size(format, channels);
1823                 if (frame_size > 0)
1824                         params->fifo_size /= (unsigned)frame_size;
1825         }
1826         return 0;
1827 }
1828
1829 /**
1830  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1831  * @substream: the pcm substream instance
1832  * @cmd: ioctl command
1833  * @arg: ioctl argument
1834  *
1835  * Processes the generic ioctl commands for PCM.
1836  * Can be passed as the ioctl callback for PCM ops.
1837  *
1838  * Return: Zero if successful, or a negative error code on failure.
1839  */
1840 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1841                       unsigned int cmd, void *arg)
1842 {
1843         switch (cmd) {
1844         case SNDRV_PCM_IOCTL1_INFO:
1845                 return 0;
1846         case SNDRV_PCM_IOCTL1_RESET:
1847                 return snd_pcm_lib_ioctl_reset(substream, arg);
1848         case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1849                 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1850         case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1851                 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1852         }
1853         return -ENXIO;
1854 }
1855
1856 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1857
1858 /**
1859  * snd_pcm_period_elapsed - update the pcm status for the next period
1860  * @substream: the pcm substream instance
1861  *
1862  * This function is called from the interrupt handler when the
1863  * PCM has processed the period size.  It will update the current
1864  * pointer, wake up sleepers, etc.
1865  *
1866  * Even if more than one periods have elapsed since the last call, you
1867  * have to call this only once.
1868  */
1869 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1870 {
1871         struct snd_pcm_runtime *runtime;
1872         unsigned long flags;
1873
1874         if (PCM_RUNTIME_CHECK(substream))
1875                 return;
1876         runtime = substream->runtime;
1877
1878         if (runtime->transfer_ack_begin)
1879                 runtime->transfer_ack_begin(substream);
1880
1881         snd_pcm_stream_lock_irqsave(substream, flags);
1882         if (!snd_pcm_running(substream) ||
1883             snd_pcm_update_hw_ptr0(substream, 1) < 0)
1884                 goto _end;
1885
1886         if (substream->timer_running)
1887                 snd_timer_interrupt(substream->timer, 1);
1888  _end:
1889         snd_pcm_stream_unlock_irqrestore(substream, flags);
1890         if (runtime->transfer_ack_end)
1891                 runtime->transfer_ack_end(substream);
1892         kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1893 }
1894
1895 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1896
1897 /*
1898  * Wait until avail_min data becomes available
1899  * Returns a negative error code if any error occurs during operation.
1900  * The available space is stored on availp.  When err = 0 and avail = 0
1901  * on the capture stream, it indicates the stream is in DRAINING state.
1902  */
1903 static int wait_for_avail(struct snd_pcm_substream *substream,
1904                               snd_pcm_uframes_t *availp)
1905 {
1906         struct snd_pcm_runtime *runtime = substream->runtime;
1907         int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1908         wait_queue_t wait;
1909         int err = 0;
1910         snd_pcm_uframes_t avail = 0;
1911         long wait_time, tout;
1912
1913         init_waitqueue_entry(&wait, current);
1914         set_current_state(TASK_INTERRUPTIBLE);
1915         add_wait_queue(&runtime->tsleep, &wait);
1916
1917         if (runtime->no_period_wakeup)
1918                 wait_time = MAX_SCHEDULE_TIMEOUT;
1919         else {
1920                 wait_time = 10;
1921                 if (runtime->rate) {
1922                         long t = runtime->period_size * 2 / runtime->rate;
1923                         wait_time = max(t, wait_time);
1924                 }
1925                 wait_time = msecs_to_jiffies(wait_time * 1000);
1926         }
1927
1928         for (;;) {
1929                 if (signal_pending(current)) {
1930                         err = -ERESTARTSYS;
1931                         break;
1932                 }
1933
1934                 /*
1935                  * We need to check if space became available already
1936                  * (and thus the wakeup happened already) first to close
1937                  * the race of space already having become available.
1938                  * This check must happen after been added to the waitqueue
1939                  * and having current state be INTERRUPTIBLE.
1940                  */
1941                 if (is_playback)
1942                         avail = snd_pcm_playback_avail(runtime);
1943                 else
1944                         avail = snd_pcm_capture_avail(runtime);
1945                 if (avail >= runtime->twake)
1946                         break;
1947                 snd_pcm_stream_unlock_irq(substream);
1948
1949                 tout = schedule_timeout(wait_time);
1950
1951                 snd_pcm_stream_lock_irq(substream);
1952                 set_current_state(TASK_INTERRUPTIBLE);
1953                 switch (runtime->status->state) {
1954                 case SNDRV_PCM_STATE_SUSPENDED:
1955                         err = -ESTRPIPE;
1956                         goto _endloop;
1957                 case SNDRV_PCM_STATE_XRUN:
1958                         err = -EPIPE;
1959                         goto _endloop;
1960                 case SNDRV_PCM_STATE_DRAINING:
1961                         if (is_playback)
1962                                 err = -EPIPE;
1963                         else
1964                                 avail = 0; /* indicate draining */
1965                         goto _endloop;
1966                 case SNDRV_PCM_STATE_OPEN:
1967                 case SNDRV_PCM_STATE_SETUP:
1968                 case SNDRV_PCM_STATE_DISCONNECTED:
1969                         err = -EBADFD;
1970                         goto _endloop;
1971                 case SNDRV_PCM_STATE_PAUSED:
1972                         continue;
1973                 }
1974                 if (!tout) {
1975                         pcm_dbg(substream->pcm,
1976                                 "%s write error (DMA or IRQ trouble?)\n",
1977                                 is_playback ? "playback" : "capture");
1978                         err = -EIO;
1979                         break;
1980                 }
1981         }
1982  _endloop:
1983         set_current_state(TASK_RUNNING);
1984         remove_wait_queue(&runtime->tsleep, &wait);
1985         *availp = avail;
1986         return err;
1987 }
1988
1989 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1990                                       unsigned int hwoff,
1991                                       unsigned long data, unsigned int off,
1992                                       snd_pcm_uframes_t frames)
1993 {
1994         struct snd_pcm_runtime *runtime = substream->runtime;
1995         int err;
1996         char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1997         if (substream->ops->copy) {
1998                 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1999                         return err;
2000         } else {
2001                 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2002                 if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
2003                         return -EFAULT;
2004         }
2005         return 0;
2006 }
2007
2008 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
2009                           unsigned long data, unsigned int off,
2010                           snd_pcm_uframes_t size);
2011
2012 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
2013                                             unsigned long data,
2014                                             snd_pcm_uframes_t size,
2015                                             int nonblock,
2016                                             transfer_f transfer)
2017 {
2018         struct snd_pcm_runtime *runtime = substream->runtime;
2019         snd_pcm_uframes_t xfer = 0;
2020         snd_pcm_uframes_t offset = 0;
2021         snd_pcm_uframes_t avail;
2022         int err = 0;
2023
2024         if (size == 0)
2025                 return 0;
2026
2027         snd_pcm_stream_lock_irq(substream);
2028         switch (runtime->status->state) {
2029         case SNDRV_PCM_STATE_PREPARED:
2030         case SNDRV_PCM_STATE_RUNNING:
2031         case SNDRV_PCM_STATE_PAUSED:
2032                 break;
2033         case SNDRV_PCM_STATE_XRUN:
2034                 err = -EPIPE;
2035                 goto _end_unlock;
2036         case SNDRV_PCM_STATE_SUSPENDED:
2037                 err = -ESTRPIPE;
2038                 goto _end_unlock;
2039         default:
2040                 err = -EBADFD;
2041                 goto _end_unlock;
2042         }
2043
2044         runtime->twake = runtime->control->avail_min ? : 1;
2045         if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2046                 snd_pcm_update_hw_ptr(substream);
2047         avail = snd_pcm_playback_avail(runtime);
2048         while (size > 0) {
2049                 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2050                 snd_pcm_uframes_t cont;
2051                 if (!avail) {
2052                         if (nonblock) {
2053                                 err = -EAGAIN;
2054                                 goto _end_unlock;
2055                         }
2056                         runtime->twake = min_t(snd_pcm_uframes_t, size,
2057                                         runtime->control->avail_min ? : 1);
2058                         err = wait_for_avail(substream, &avail);
2059                         if (err < 0)
2060                                 goto _end_unlock;
2061                 }
2062                 frames = size > avail ? avail : size;
2063                 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2064                 if (frames > cont)
2065                         frames = cont;
2066                 if (snd_BUG_ON(!frames)) {
2067                         runtime->twake = 0;
2068                         snd_pcm_stream_unlock_irq(substream);
2069                         return -EINVAL;
2070                 }
2071                 appl_ptr = runtime->control->appl_ptr;
2072                 appl_ofs = appl_ptr % runtime->buffer_size;
2073                 snd_pcm_stream_unlock_irq(substream);
2074                 err = transfer(substream, appl_ofs, data, offset, frames);
2075                 snd_pcm_stream_lock_irq(substream);
2076                 if (err < 0)
2077                         goto _end_unlock;
2078                 switch (runtime->status->state) {
2079                 case SNDRV_PCM_STATE_XRUN:
2080                         err = -EPIPE;
2081                         goto _end_unlock;
2082                 case SNDRV_PCM_STATE_SUSPENDED:
2083                         err = -ESTRPIPE;
2084                         goto _end_unlock;
2085                 default:
2086                         break;
2087                 }
2088                 appl_ptr += frames;
2089                 if (appl_ptr >= runtime->boundary)
2090                         appl_ptr -= runtime->boundary;
2091                 runtime->control->appl_ptr = appl_ptr;
2092                 if (substream->ops->ack)
2093                         substream->ops->ack(substream);
2094
2095                 offset += frames;
2096                 size -= frames;
2097                 xfer += frames;
2098                 avail -= frames;
2099                 if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2100                     snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2101                         err = snd_pcm_start(substream);
2102                         if (err < 0)
2103                                 goto _end_unlock;
2104                 }
2105         }
2106  _end_unlock:
2107         runtime->twake = 0;
2108         if (xfer > 0 && err >= 0)
2109                 snd_pcm_update_state(substream, runtime);
2110         snd_pcm_stream_unlock_irq(substream);
2111         return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2112 }
2113
2114 /* sanity-check for read/write methods */
2115 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2116 {
2117         struct snd_pcm_runtime *runtime;
2118         if (PCM_RUNTIME_CHECK(substream))
2119                 return -ENXIO;
2120         runtime = substream->runtime;
2121         if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
2122                 return -EINVAL;
2123         if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2124                 return -EBADFD;
2125         return 0;
2126 }
2127
2128 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
2129 {
2130         struct snd_pcm_runtime *runtime;
2131         int nonblock;
2132         int err;
2133
2134         err = pcm_sanity_check(substream);
2135         if (err < 0)
2136                 return err;
2137         runtime = substream->runtime;
2138         nonblock = !!(substream->f_flags & O_NONBLOCK);
2139
2140         if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2141             runtime->channels > 1)
2142                 return -EINVAL;
2143         return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
2144                                   snd_pcm_lib_write_transfer);
2145 }
2146
2147 EXPORT_SYMBOL(snd_pcm_lib_write);
2148
2149 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
2150                                        unsigned int hwoff,
2151                                        unsigned long data, unsigned int off,
2152                                        snd_pcm_uframes_t frames)
2153 {
2154         struct snd_pcm_runtime *runtime = substream->runtime;
2155         int err;
2156         void __user **bufs = (void __user **)data;
2157         int channels = runtime->channels;
2158         int c;
2159         if (substream->ops->copy) {
2160                 if (snd_BUG_ON(!substream->ops->silence))
2161                         return -EINVAL;
2162                 for (c = 0; c < channels; ++c, ++bufs) {
2163                         if (*bufs == NULL) {
2164                                 if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
2165                                         return err;
2166                         } else {
2167                                 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2168                                 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2169                                         return err;
2170                         }
2171                 }
2172         } else {
2173                 /* default transfer behaviour */
2174                 size_t dma_csize = runtime->dma_bytes / channels;
2175                 for (c = 0; c < channels; ++c, ++bufs) {
2176                         char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2177                         if (*bufs == NULL) {
2178                                 snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
2179                         } else {
2180                                 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2181                                 if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
2182                                         return -EFAULT;
2183                         }
2184                 }
2185         }
2186         return 0;
2187 }
2188
2189 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
2190                                      void __user **bufs,
2191                                      snd_pcm_uframes_t frames)
2192 {
2193         struct snd_pcm_runtime *runtime;
2194         int nonblock;
2195         int err;
2196
2197         err = pcm_sanity_check(substream);
2198         if (err < 0)
2199                 return err;
2200         runtime = substream->runtime;
2201         nonblock = !!(substream->f_flags & O_NONBLOCK);
2202
2203         if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2204                 return -EINVAL;
2205         return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2206                                   nonblock, snd_pcm_lib_writev_transfer);
2207 }
2208
2209 EXPORT_SYMBOL(snd_pcm_lib_writev);
2210
2211 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
2212                                      unsigned int hwoff,
2213                                      unsigned long data, unsigned int off,
2214                                      snd_pcm_uframes_t frames)
2215 {
2216         struct snd_pcm_runtime *runtime = substream->runtime;
2217         int err;
2218         char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2219         if (substream->ops->copy) {
2220                 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2221                         return err;
2222         } else {
2223                 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2224                 if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2225                         return -EFAULT;
2226         }
2227         return 0;
2228 }
2229
2230 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2231                                            unsigned long data,
2232                                            snd_pcm_uframes_t size,
2233                                            int nonblock,
2234                                            transfer_f transfer)
2235 {
2236         struct snd_pcm_runtime *runtime = substream->runtime;
2237         snd_pcm_uframes_t xfer = 0;
2238         snd_pcm_uframes_t offset = 0;
2239         snd_pcm_uframes_t avail;
2240         int err = 0;
2241
2242         if (size == 0)
2243                 return 0;
2244
2245         snd_pcm_stream_lock_irq(substream);
2246         switch (runtime->status->state) {
2247         case SNDRV_PCM_STATE_PREPARED:
2248                 if (size >= runtime->start_threshold) {
2249                         err = snd_pcm_start(substream);
2250                         if (err < 0)
2251                                 goto _end_unlock;
2252                 }
2253                 break;
2254         case SNDRV_PCM_STATE_DRAINING:
2255         case SNDRV_PCM_STATE_RUNNING:
2256         case SNDRV_PCM_STATE_PAUSED:
2257                 break;
2258         case SNDRV_PCM_STATE_XRUN:
2259                 err = -EPIPE;
2260                 goto _end_unlock;
2261         case SNDRV_PCM_STATE_SUSPENDED:
2262                 err = -ESTRPIPE;
2263                 goto _end_unlock;
2264         default:
2265                 err = -EBADFD;
2266                 goto _end_unlock;
2267         }
2268
2269         runtime->twake = runtime->control->avail_min ? : 1;
2270         if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2271                 snd_pcm_update_hw_ptr(substream);
2272         avail = snd_pcm_capture_avail(runtime);
2273         while (size > 0) {
2274                 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2275                 snd_pcm_uframes_t cont;
2276                 if (!avail) {
2277                         if (runtime->status->state ==
2278                             SNDRV_PCM_STATE_DRAINING) {
2279                                 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2280                                 goto _end_unlock;
2281                         }
2282                         if (nonblock) {
2283                                 err = -EAGAIN;
2284                                 goto _end_unlock;
2285                         }
2286                         runtime->twake = min_t(snd_pcm_uframes_t, size,
2287                                         runtime->control->avail_min ? : 1);
2288                         err = wait_for_avail(substream, &avail);
2289                         if (err < 0)
2290                                 goto _end_unlock;
2291                         if (!avail)
2292                                 continue; /* draining */
2293                 }
2294                 frames = size > avail ? avail : size;
2295                 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2296                 if (frames > cont)
2297                         frames = cont;
2298                 if (snd_BUG_ON(!frames)) {
2299                         runtime->twake = 0;
2300                         snd_pcm_stream_unlock_irq(substream);
2301                         return -EINVAL;
2302                 }
2303                 appl_ptr = runtime->control->appl_ptr;
2304                 appl_ofs = appl_ptr % runtime->buffer_size;
2305                 snd_pcm_stream_unlock_irq(substream);
2306                 err = transfer(substream, appl_ofs, data, offset, frames);
2307                 snd_pcm_stream_lock_irq(substream);
2308                 if (err < 0)
2309                         goto _end_unlock;
2310                 switch (runtime->status->state) {
2311                 case SNDRV_PCM_STATE_XRUN:
2312                         err = -EPIPE;
2313                         goto _end_unlock;
2314                 case SNDRV_PCM_STATE_SUSPENDED:
2315                         err = -ESTRPIPE;
2316                         goto _end_unlock;
2317                 default:
2318                         break;
2319                 }
2320                 appl_ptr += frames;
2321                 if (appl_ptr >= runtime->boundary)
2322                         appl_ptr -= runtime->boundary;
2323                 runtime->control->appl_ptr = appl_ptr;
2324                 if (substream->ops->ack)
2325                         substream->ops->ack(substream);
2326
2327                 offset += frames;
2328                 size -= frames;
2329                 xfer += frames;
2330                 avail -= frames;
2331         }
2332  _end_unlock:
2333         runtime->twake = 0;
2334         if (xfer > 0 && err >= 0)
2335                 snd_pcm_update_state(substream, runtime);
2336         snd_pcm_stream_unlock_irq(substream);
2337         return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2338 }
2339
2340 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2341 {
2342         struct snd_pcm_runtime *runtime;
2343         int nonblock;
2344         int err;
2345
2346         err = pcm_sanity_check(substream);
2347         if (err < 0)
2348                 return err;
2349         runtime = substream->runtime;
2350         nonblock = !!(substream->f_flags & O_NONBLOCK);
2351         if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2352                 return -EINVAL;
2353         return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2354 }
2355
2356 EXPORT_SYMBOL(snd_pcm_lib_read);
2357
2358 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2359                                       unsigned int hwoff,
2360                                       unsigned long data, unsigned int off,
2361                                       snd_pcm_uframes_t frames)
2362 {
2363         struct snd_pcm_runtime *runtime = substream->runtime;
2364         int err;
2365         void __user **bufs = (void __user **)data;
2366         int channels = runtime->channels;
2367         int c;
2368         if (substream->ops->copy) {
2369                 for (c = 0; c < channels; ++c, ++bufs) {
2370                         char __user *buf;
2371                         if (*bufs == NULL)
2372                                 continue;
2373                         buf = *bufs + samples_to_bytes(runtime, off);
2374                         if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2375                                 return err;
2376                 }
2377         } else {
2378                 snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2379                 for (c = 0; c < channels; ++c, ++bufs) {
2380                         char *hwbuf;
2381                         char __user *buf;
2382                         if (*bufs == NULL)
2383                                 continue;
2384
2385                         hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2386                         buf = *bufs + samples_to_bytes(runtime, off);
2387                         if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2388                                 return -EFAULT;
2389                 }
2390         }
2391         return 0;
2392 }
2393
2394 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2395                                     void __user **bufs,
2396                                     snd_pcm_uframes_t frames)
2397 {
2398         struct snd_pcm_runtime *runtime;
2399         int nonblock;
2400         int err;
2401
2402         err = pcm_sanity_check(substream);
2403         if (err < 0)
2404                 return err;
2405         runtime = substream->runtime;
2406         if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2407                 return -EBADFD;
2408
2409         nonblock = !!(substream->f_flags & O_NONBLOCK);
2410         if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2411                 return -EINVAL;
2412         return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2413 }
2414
2415 EXPORT_SYMBOL(snd_pcm_lib_readv);
2416
2417 /*
2418  * standard channel mapping helpers
2419  */
2420
2421 /* default channel maps for multi-channel playbacks, up to 8 channels */
2422 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2423         { .channels = 1,
2424           .map = { SNDRV_CHMAP_MONO } },
2425         { .channels = 2,
2426           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2427         { .channels = 4,
2428           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2429                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2430         { .channels = 6,
2431           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2432                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2433                    SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2434         { .channels = 8,
2435           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2436                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2437                    SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2438                    SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2439         { }
2440 };
2441 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2442
2443 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2444 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2445         { .channels = 1,
2446           .map = { SNDRV_CHMAP_MONO } },
2447         { .channels = 2,
2448           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2449         { .channels = 4,
2450           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2451                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2452         { .channels = 6,
2453           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2454                    SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2455                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2456         { .channels = 8,
2457           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2458                    SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2459                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2460                    SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2461         { }
2462 };
2463 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2464
2465 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2466 {
2467         if (ch > info->max_channels)
2468                 return false;
2469         return !info->channel_mask || (info->channel_mask & (1U << ch));
2470 }
2471
2472 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2473                               struct snd_ctl_elem_info *uinfo)
2474 {
2475         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2476
2477         uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2478         uinfo->count = 0;
2479         uinfo->count = info->max_channels;
2480         uinfo->value.integer.min = 0;
2481         uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2482         return 0;
2483 }
2484
2485 /* get callback for channel map ctl element
2486  * stores the channel position firstly matching with the current channels
2487  */
2488 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2489                              struct snd_ctl_elem_value *ucontrol)
2490 {
2491         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2492         unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2493         struct snd_pcm_substream *substream;
2494         const struct snd_pcm_chmap_elem *map;
2495
2496         if (snd_BUG_ON(!info->chmap))
2497                 return -EINVAL;
2498         substream = snd_pcm_chmap_substream(info, idx);
2499         if (!substream)
2500                 return -ENODEV;
2501         memset(ucontrol->value.integer.value, 0,
2502                sizeof(ucontrol->value.integer.value));
2503         if (!substream->runtime)
2504                 return 0; /* no channels set */
2505         for (map = info->chmap; map->channels; map++) {
2506                 int i;
2507                 if (map->channels == substream->runtime->channels &&
2508                     valid_chmap_channels(info, map->channels)) {
2509                         for (i = 0; i < map->channels; i++)
2510                                 ucontrol->value.integer.value[i] = map->map[i];
2511                         return 0;
2512                 }
2513         }
2514         return -EINVAL;
2515 }
2516
2517 /* tlv callback for channel map ctl element
2518  * expands the pre-defined channel maps in a form of TLV
2519  */
2520 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2521                              unsigned int size, unsigned int __user *tlv)
2522 {
2523         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2524         const struct snd_pcm_chmap_elem *map;
2525         unsigned int __user *dst;
2526         int c, count = 0;
2527
2528         if (snd_BUG_ON(!info->chmap))
2529                 return -EINVAL;
2530         if (size < 8)
2531                 return -ENOMEM;
2532         if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2533                 return -EFAULT;
2534         size -= 8;
2535         dst = tlv + 2;
2536         for (map = info->chmap; map->channels; map++) {
2537                 int chs_bytes = map->channels * 4;
2538                 if (!valid_chmap_channels(info, map->channels))
2539                         continue;
2540                 if (size < 8)
2541                         return -ENOMEM;
2542                 if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2543                     put_user(chs_bytes, dst + 1))
2544                         return -EFAULT;
2545                 dst += 2;
2546                 size -= 8;
2547                 count += 8;
2548                 if (size < chs_bytes)
2549                         return -ENOMEM;
2550                 size -= chs_bytes;
2551                 count += chs_bytes;
2552                 for (c = 0; c < map->channels; c++) {
2553                         if (put_user(map->map[c], dst))
2554                                 return -EFAULT;
2555                         dst++;
2556                 }
2557         }
2558         if (put_user(count, tlv + 1))
2559                 return -EFAULT;
2560         return 0;
2561 }
2562
2563 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2564 {
2565         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2566         info->pcm->streams[info->stream].chmap_kctl = NULL;
2567         kfree(info);
2568 }
2569
2570 /**
2571  * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2572  * @pcm: the assigned PCM instance
2573  * @stream: stream direction
2574  * @chmap: channel map elements (for query)
2575  * @max_channels: the max number of channels for the stream
2576  * @private_value: the value passed to each kcontrol's private_value field
2577  * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2578  *
2579  * Create channel-mapping control elements assigned to the given PCM stream(s).
2580  * Return: Zero if successful, or a negative error value.
2581  */
2582 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2583                            const struct snd_pcm_chmap_elem *chmap,
2584                            int max_channels,
2585                            unsigned long private_value,
2586                            struct snd_pcm_chmap **info_ret)
2587 {
2588         struct snd_pcm_chmap *info;
2589         struct snd_kcontrol_new knew = {
2590                 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
2591                 .access = SNDRV_CTL_ELEM_ACCESS_READ |
2592                         SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2593                         SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2594                 .info = pcm_chmap_ctl_info,
2595                 .get = pcm_chmap_ctl_get,
2596                 .tlv.c = pcm_chmap_ctl_tlv,
2597         };
2598         int err;
2599
2600         info = kzalloc(sizeof(*info), GFP_KERNEL);
2601         if (!info)
2602                 return -ENOMEM;
2603         info->pcm = pcm;
2604         info->stream = stream;
2605         info->chmap = chmap;
2606         info->max_channels = max_channels;
2607         if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2608                 knew.name = "Playback Channel Map";
2609         else
2610                 knew.name = "Capture Channel Map";
2611         knew.device = pcm->device;
2612         knew.count = pcm->streams[stream].substream_count;
2613         knew.private_value = private_value;
2614         info->kctl = snd_ctl_new1(&knew, info);
2615         if (!info->kctl) {
2616                 kfree(info);
2617                 return -ENOMEM;
2618         }
2619         info->kctl->private_free = pcm_chmap_ctl_private_free;
2620         err = snd_ctl_add(pcm->card, info->kctl);
2621         if (err < 0)
2622                 return err;
2623         pcm->streams[stream].chmap_kctl = info->kctl;
2624         if (info_ret)
2625                 *info_ret = info;
2626         return 0;
2627 }
2628 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);