sound/core/pcm_lib.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Digital Audio (PCM) abstract layer
   4  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   5  *                   Abramo Bagnara <abramo@alsa-project.org>
   6  */
   7
   8 #include <linux/slab.h>
   9 #include <linux/sched/signal.h>
  10 #include <linux/time.h>
  11 #include <linux/math64.h>
  12 #include <linux/export.h>
  13 #include <sound/core.h>
  14 #include <sound/control.h>
  15 #include <sound/tlv.h>
  16 #include <sound/info.h>
  17 #include <sound/pcm.h>
  18 #include <sound/pcm_params.h>
  19 #include <sound/timer.h>
  20
  21 #include "pcm_local.h"
  22
  23 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
  24 #define CREATE_TRACE_POINTS
  25 #include "pcm_trace.h"
  26 #else
  27 #define trace_hwptr(substream, pos, in_interrupt)
  28 #define trace_xrun(substream)
  29 #define trace_hw_ptr_error(substream, reason)
  30 #define trace_applptr(substream, prev, curr)
  31 #endif
  32
  33 static int fill_silence_frames(struct snd_pcm_substream *substream,
  34                                snd_pcm_uframes_t off, snd_pcm_uframes_t frames);
  35
  36 /*
  37  * fill ring buffer with silence
  38  * runtime->silence_start: starting pointer to silence area
  39  * runtime->silence_filled: size filled with silence
  40  * runtime->silence_threshold: threshold from application
  41  * runtime->silence_size: maximal size from application
  42  *
  43  * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
  44  */
  45 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
  46 {
  47         struct snd_pcm_runtime *runtime = substream->runtime;
  48         snd_pcm_uframes_t frames, ofs, transfer;
  49         int err;
  50
  51         if (runtime->silence_size < runtime->boundary) {
  52                 snd_pcm_sframes_t noise_dist, n;
  53                 snd_pcm_uframes_t appl_ptr = READ_ONCE(runtime->control->appl_ptr);
  54                 if (runtime->silence_start != appl_ptr) {
  55                         n = appl_ptr - runtime->silence_start;
  56                         if (n < 0)
  57                                 n += runtime->boundary;
  58                         if ((snd_pcm_uframes_t)n < runtime->silence_filled)
  59                                 runtime->silence_filled -= n;
  60                         else
  61                                 runtime->silence_filled = 0;
  62                         runtime->silence_start = appl_ptr;
  63                 }
  64                 if (runtime->silence_filled >= runtime->buffer_size)
  65                         return;
  66                 noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
  67                 if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
  68                         return;
  69                 frames = runtime->silence_threshold - noise_dist;
  70                 if (frames > runtime->silence_size)
  71                         frames = runtime->silence_size;
  72         } else {
  73                 if (new_hw_ptr == ULONG_MAX) {  /* initialization */
  74                         snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
  75                         if (avail > runtime->buffer_size)
  76                                 avail = runtime->buffer_size;
  77                         runtime->silence_filled = avail > 0 ? avail : 0;
  78                         runtime->silence_start = (runtime->status->hw_ptr +
  79                                                   runtime->silence_filled) %
  80                                                  runtime->boundary;
  81                 } else {
  82                         ofs = runtime->status->hw_ptr;
  83                         frames = new_hw_ptr - ofs;
  84                         if ((snd_pcm_sframes_t)frames < 0)
  85                                 frames += runtime->boundary;
  86                         runtime->silence_filled -= frames;
  87                         if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
  88                                 runtime->silence_filled = 0;
  89                                 runtime->silence_start = new_hw_ptr;
  90                         } else {
  91                                 runtime->silence_start = ofs;
  92                         }
  93                 }
  94                 frames = runtime->buffer_size - runtime->silence_filled;
  95         }
  96         if (snd_BUG_ON(frames > runtime->buffer_size))
  97                 return;
  98         if (frames == 0)
  99                 return;
 100         ofs = runtime->silence_start % runtime->buffer_size;
 101         while (frames > 0) {
 102                 transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
 103                 err = fill_silence_frames(substream, ofs, transfer);
 104                 snd_BUG_ON(err < 0);
 105                 runtime->silence_filled += transfer;
 106                 frames -= transfer;
 107                 ofs = 0;
 108         }
 109 }
 110
 111 #ifdef CONFIG_SND_DEBUG
 112 void snd_pcm_debug_name(struct snd_pcm_substream *substream,
 113                            char *name, size_t len)
 114 {
 115         snprintf(name, len, "pcmC%dD%d%c:%d",
 116                  substream->pcm->card->number,
 117                  substream->pcm->device,
 118                  substream->stream ? 'c' : 'p',
 119                  substream->number);
 120 }
 121 EXPORT_SYMBOL(snd_pcm_debug_name);
 122 #endif
 123
 124 #define XRUN_DEBUG_BASIC        (1<<0)
 125 #define XRUN_DEBUG_STACK        (1<<1)  /* dump also stack */
 126 #define XRUN_DEBUG_JIFFIESCHECK (1<<2)  /* do jiffies check */
 127
 128 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 129
 130 #define xrun_debug(substream, mask) \
 131                         ((substream)->pstr->xrun_debug & (mask))
 132 #else
 133 #define xrun_debug(substream, mask)     0
 134 #endif
 135
 136 #define dump_stack_on_xrun(substream) do {                      \
 137                 if (xrun_debug(substream, XRUN_DEBUG_STACK))    \
 138                         dump_stack();                           \
 139         } while (0)
 140
 141 /* call with stream lock held */
 142 void __snd_pcm_xrun(struct snd_pcm_substream *substream)
 143 {
 144         struct snd_pcm_runtime *runtime = substream->runtime;
 145
 146         trace_xrun(substream);
 147         if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
 148                 struct timespec64 tstamp;
 149
 150                 snd_pcm_gettime(runtime, &tstamp);
 151                 runtime->status->tstamp.tv_sec = tstamp.tv_sec;
 152                 runtime->status->tstamp.tv_nsec = tstamp.tv_nsec;
 153         }
 154         snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 155         if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
 156                 char name[16];
 157                 snd_pcm_debug_name(substream, name, sizeof(name));
 158                 pcm_warn(substream->pcm, "XRUN: %s\n", name);
 159                 dump_stack_on_xrun(substream);
 160         }
 161 }
 162
 163 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 164 #define hw_ptr_error(substream, in_interrupt, reason, fmt, args...)     \
 165         do {                                                            \
 166                 trace_hw_ptr_error(substream, reason);  \
 167                 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {          \
 168                         pr_err_ratelimited("ALSA: PCM: [%c] " reason ": " fmt, \
 169                                            (in_interrupt) ? 'Q' : 'P', ##args); \
 170                         dump_stack_on_xrun(substream);                  \
 171                 }                                                       \
 172         } while (0)
 173
 174 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
 175
 176 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
 177
 178 #endif
 179
 180 int snd_pcm_update_state(struct snd_pcm_substream *substream,
 181                          struct snd_pcm_runtime *runtime)
 182 {
 183         snd_pcm_uframes_t avail;
 184
 185         avail = snd_pcm_avail(substream);
 186         if (avail > runtime->avail_max)
 187                 runtime->avail_max = avail;
 188         if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
 189                 if (avail >= runtime->buffer_size) {
 190                         snd_pcm_drain_done(substream);
 191                         return -EPIPE;
 192                 }
 193         } else {
 194                 if (avail >= runtime->stop_threshold) {
 195                         __snd_pcm_xrun(substream);
 196                         return -EPIPE;
 197                 }
 198         }
 199         if (runtime->twake) {
 200                 if (avail >= runtime->twake)
 201                         wake_up(&runtime->tsleep);
 202         } else if (avail >= runtime->control->avail_min)
 203                 wake_up(&runtime->sleep);
 204         return 0;
 205 }
 206
 207 static void update_audio_tstamp(struct snd_pcm_substream *substream,
 208                                 struct timespec64 *curr_tstamp,
 209                                 struct timespec64 *audio_tstamp)
 210 {
 211         struct snd_pcm_runtime *runtime = substream->runtime;
 212         u64 audio_frames, audio_nsecs;
 213         struct timespec64 driver_tstamp;
 214
 215         if (runtime->tstamp_mode != SNDRV_PCM_TSTAMP_ENABLE)
 216                 return;
 217
 218         if (!(substream->ops->get_time_info) ||
 219                 (runtime->audio_tstamp_report.actual_type ==
 220                         SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
 221
 222                 /*
 223                  * provide audio timestamp derived from pointer position
 224                  * add delay only if requested
 225                  */
 226
 227                 audio_frames = runtime->hw_ptr_wrap + runtime->status->hw_ptr;
 228
 229                 if (runtime->audio_tstamp_config.report_delay) {
 230                         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 231                                 audio_frames -=  runtime->delay;
 232                         else
 233                                 audio_frames +=  runtime->delay;
 234                 }
 235                 audio_nsecs = div_u64(audio_frames * 1000000000LL,
 236                                 runtime->rate);
 237                 *audio_tstamp = ns_to_timespec64(audio_nsecs);
 238         }
 239
 240         if (runtime->status->audio_tstamp.tv_sec != audio_tstamp->tv_sec ||
 241             runtime->status->audio_tstamp.tv_nsec != audio_tstamp->tv_nsec) {
 242                 runtime->status->audio_tstamp.tv_sec = audio_tstamp->tv_sec;
 243                 runtime->status->audio_tstamp.tv_nsec = audio_tstamp->tv_nsec;
 244                 runtime->status->tstamp.tv_sec = curr_tstamp->tv_sec;
 245                 runtime->status->tstamp.tv_nsec = curr_tstamp->tv_nsec;
 246         }
 247
 248
 249         /*
 250          * re-take a driver timestamp to let apps detect if the reference tstamp
 251          * read by low-level hardware was provided with a delay
 252          */
 253         snd_pcm_gettime(substream->runtime, &driver_tstamp);
 254         runtime->driver_tstamp = driver_tstamp;
 255 }
 256
 257 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
 258                                   unsigned int in_interrupt)
 259 {
 260         struct snd_pcm_runtime *runtime = substream->runtime;
 261         snd_pcm_uframes_t pos;
 262         snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
 263         snd_pcm_sframes_t hdelta, delta;
 264         unsigned long jdelta;
 265         unsigned long curr_jiffies;
 266         struct timespec64 curr_tstamp;
 267         struct timespec64 audio_tstamp;
 268         int crossed_boundary = 0;
 269
 270         old_hw_ptr = runtime->status->hw_ptr;
 271
 272         /*
 273          * group pointer, time and jiffies reads to allow for more
 274          * accurate correlations/corrections.
 275          * The values are stored at the end of this routine after
 276          * corrections for hw_ptr position
 277          */
 278         pos = substream->ops->pointer(substream);
 279         curr_jiffies = jiffies;
 280         if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
 281                 if ((substream->ops->get_time_info) &&
 282                         (runtime->audio_tstamp_config.type_requested != SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
 283                         substream->ops->get_time_info(substream, &curr_tstamp,
 284                                                 &audio_tstamp,
 285                                                 &runtime->audio_tstamp_config,
 286                                                 &runtime->audio_tstamp_report);
 287
 288                         /* re-test in case tstamp type is not supported in hardware and was demoted to DEFAULT */
 289                         if (runtime->audio_tstamp_report.actual_type == SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)
 290                                 snd_pcm_gettime(runtime, &curr_tstamp);
 291                 } else
 292                         snd_pcm_gettime(runtime, &curr_tstamp);
 293         }
 294
 295         if (pos == SNDRV_PCM_POS_XRUN) {
 296                 __snd_pcm_xrun(substream);
 297                 return -EPIPE;
 298         }
 299         if (pos >= runtime->buffer_size) {
 300                 if (printk_ratelimit()) {
 301                         char name[16];
 302                         snd_pcm_debug_name(substream, name, sizeof(name));
 303                         pcm_err(substream->pcm,
 304                                 "invalid position: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
 305                                 name, pos, runtime->buffer_size,
 306                                 runtime->period_size);
 307                 }
 308                 pos = 0;
 309         }
 310         pos -= pos % runtime->min_align;
 311         trace_hwptr(substream, pos, in_interrupt);
 312         hw_base = runtime->hw_ptr_base;
 313         new_hw_ptr = hw_base + pos;
 314         if (in_interrupt) {
 315                 /* we know that one period was processed */
 316                 /* delta = "expected next hw_ptr" for in_interrupt != 0 */
 317                 delta = runtime->hw_ptr_interrupt + runtime->period_size;
 318                 if (delta > new_hw_ptr) {
 319                         /* check for double acknowledged interrupts */
 320                         hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 321                         if (hdelta > runtime->hw_ptr_buffer_jiffies/2 + 1) {
 322                                 hw_base += runtime->buffer_size;
 323                                 if (hw_base >= runtime->boundary) {
 324                                         hw_base = 0;
 325                                         crossed_boundary++;
 326                                 }
 327                                 new_hw_ptr = hw_base + pos;
 328                                 goto __delta;
 329                         }
 330                 }
 331         }
 332         /* new_hw_ptr might be lower than old_hw_ptr in case when */
 333         /* pointer crosses the end of the ring buffer */
 334         if (new_hw_ptr < old_hw_ptr) {
 335                 hw_base += runtime->buffer_size;
 336                 if (hw_base >= runtime->boundary) {
 337                         hw_base = 0;
 338                         crossed_boundary++;
 339                 }
 340                 new_hw_ptr = hw_base + pos;
 341         }
 342       __delta:
 343         delta = new_hw_ptr - old_hw_ptr;
 344         if (delta < 0)
 345                 delta += runtime->boundary;
 346
 347         if (runtime->no_period_wakeup) {
 348                 snd_pcm_sframes_t xrun_threshold;
 349                 /*
 350                  * Without regular period interrupts, we have to check
 351                  * the elapsed time to detect xruns.
 352                  */
 353                 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 354                 if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
 355                         goto no_delta_check;
 356                 hdelta = jdelta - delta * HZ / runtime->rate;
 357                 xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
 358                 while (hdelta > xrun_threshold) {
 359                         delta += runtime->buffer_size;
 360                         hw_base += runtime->buffer_size;
 361                         if (hw_base >= runtime->boundary) {
 362                                 hw_base = 0;
 363                                 crossed_boundary++;
 364                         }
 365                         new_hw_ptr = hw_base + pos;
 366                         hdelta -= runtime->hw_ptr_buffer_jiffies;
 367                 }
 368                 goto no_delta_check;
 369         }
 370
 371         /* something must be really wrong */
 372         if (delta >= runtime->buffer_size + runtime->period_size) {
 373                 hw_ptr_error(substream, in_interrupt, "Unexpected hw_ptr",
 374                              "(stream=%i, pos=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
 375                              substream->stream, (long)pos,
 376                              (long)new_hw_ptr, (long)old_hw_ptr);
 377                 return 0;
 378         }
 379
 380         /* Do jiffies check only in xrun_debug mode */
 381         if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
 382                 goto no_jiffies_check;
 383
 384         /* Skip the jiffies check for hardwares with BATCH flag.
 385          * Such hardware usually just increases the position at each IRQ,
 386          * thus it can't give any strange position.
 387          */
 388         if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
 389                 goto no_jiffies_check;
 390         hdelta = delta;
 391         if (hdelta < runtime->delay)
 392                 goto no_jiffies_check;
 393         hdelta -= runtime->delay;
 394         jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 395         if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
 396                 delta = jdelta /
 397                         (((runtime->period_size * HZ) / runtime->rate)
 398                                                                 + HZ/100);
 399                 /* move new_hw_ptr according jiffies not pos variable */
 400                 new_hw_ptr = old_hw_ptr;
 401                 hw_base = delta;
 402                 /* use loop to avoid checks for delta overflows */
 403                 /* the delta value is small or zero in most cases */
 404                 while (delta > 0) {
 405                         new_hw_ptr += runtime->period_size;
 406                         if (new_hw_ptr >= runtime->boundary) {
 407                                 new_hw_ptr -= runtime->boundary;
 408                                 crossed_boundary--;
 409                         }
 410                         delta--;
 411                 }
 412                 /* align hw_base to buffer_size */
 413                 hw_ptr_error(substream, in_interrupt, "hw_ptr skipping",
 414                              "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
 415                              (long)pos, (long)hdelta,
 416                              (long)runtime->period_size, jdelta,
 417                              ((hdelta * HZ) / runtime->rate), hw_base,
 418                              (unsigned long)old_hw_ptr,
 419                              (unsigned long)new_hw_ptr);
 420                 /* reset values to proper state */
 421                 delta = 0;
 422                 hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
 423         }
 424  no_jiffies_check:
 425         if (delta > runtime->period_size + runtime->period_size / 2) {
 426                 hw_ptr_error(substream, in_interrupt,
 427                              "Lost interrupts?",
 428                              "(stream=%i, delta=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
 429                              substream->stream, (long)delta,
 430                              (long)new_hw_ptr,
 431                              (long)old_hw_ptr);
 432         }
 433
 434  no_delta_check:
 435         if (runtime->status->hw_ptr == new_hw_ptr) {
 436                 runtime->hw_ptr_jiffies = curr_jiffies;
 437                 update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
 438                 return 0;
 439         }
 440
 441         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 442             runtime->silence_size > 0)
 443                 snd_pcm_playback_silence(substream, new_hw_ptr);
 444
 445         if (in_interrupt) {
 446                 delta = new_hw_ptr - runtime->hw_ptr_interrupt;
 447                 if (delta < 0)
 448                         delta += runtime->boundary;
 449                 delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
 450                 runtime->hw_ptr_interrupt += delta;
 451                 if (runtime->hw_ptr_interrupt >= runtime->boundary)
 452                         runtime->hw_ptr_interrupt -= runtime->boundary;
 453         }
 454         runtime->hw_ptr_base = hw_base;
 455         runtime->status->hw_ptr = new_hw_ptr;
 456         runtime->hw_ptr_jiffies = curr_jiffies;
 457         if (crossed_boundary) {
 458                 snd_BUG_ON(crossed_boundary != 1);
 459                 runtime->hw_ptr_wrap += runtime->boundary;
 460         }
 461
 462         update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
 463
 464         return snd_pcm_update_state(substream, runtime);
 465 }
 466
 467 /* CAUTION: call it with irq disabled */
 468 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
 469 {
 470         return snd_pcm_update_hw_ptr0(substream, 0);
 471 }
 472
 473 /**
 474  * snd_pcm_set_ops - set the PCM operators
 475  * @pcm: the pcm instance
 476  * @direction: stream direction, SNDRV_PCM_STREAM_XXX
 477  * @ops: the operator table
 478  *
 479  * Sets the given PCM operators to the pcm instance.
 480  */
 481 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
 482                      const struct snd_pcm_ops *ops)
 483 {
 484         struct snd_pcm_str *stream = &pcm->streams[direction];
 485         struct snd_pcm_substream *substream;
 486
 487         for (substream = stream->substream; substream != NULL; substream = substream->next)
 488                 substream->ops = ops;
 489 }
 490 EXPORT_SYMBOL(snd_pcm_set_ops);
 491
 492 /**
 493  * snd_pcm_set_sync - set the PCM sync id
 494  * @substream: the pcm substream
 495  *
 496  * Sets the PCM sync identifier for the card.
 497  */
 498 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
 499 {
 500         struct snd_pcm_runtime *runtime = substream->runtime;
 501
 502         runtime->sync.id32[0] = substream->pcm->card->number;
 503         runtime->sync.id32[1] = -1;
 504         runtime->sync.id32[2] = -1;
 505         runtime->sync.id32[3] = -1;
 506 }
 507 EXPORT_SYMBOL(snd_pcm_set_sync);
 508
 509 /*
 510  *  Standard ioctl routine
 511  */
 512
 513 static inline unsigned int div32(unsigned int a, unsigned int b,
 514                                  unsigned int *r)
 515 {
 516         if (b == 0) {
 517                 *r = 0;
 518                 return UINT_MAX;
 519         }
 520         *r = a % b;
 521         return a / b;
 522 }
 523
 524 static inline unsigned int div_down(unsigned int a, unsigned int b)
 525 {
 526         if (b == 0)
 527                 return UINT_MAX;
 528         return a / b;
 529 }
 530
 531 static inline unsigned int div_up(unsigned int a, unsigned int b)
 532 {
 533         unsigned int r;
 534         unsigned int q;
 535         if (b == 0)
 536                 return UINT_MAX;
 537         q = div32(a, b, &r);
 538         if (r)
 539                 ++q;
 540         return q;
 541 }
 542
 543 static inline unsigned int mul(unsigned int a, unsigned int b)
 544 {
 545         if (a == 0)
 546                 return 0;
 547         if (div_down(UINT_MAX, a) < b)
 548                 return UINT_MAX;
 549         return a * b;
 550 }
 551
 552 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
 553                                     unsigned int c, unsigned int *r)
 554 {
 555         u_int64_t n = (u_int64_t) a * b;
 556         if (c == 0) {
 557                 *r = 0;
 558                 return UINT_MAX;
 559         }
 560         n = div_u64_rem(n, c, r);
 561         if (n >= UINT_MAX) {
 562                 *r = 0;
 563                 return UINT_MAX;
 564         }
 565         return n;
 566 }
 567
 568 /**
 569  * snd_interval_refine - refine the interval value of configurator
 570  * @i: the interval value to refine
 571  * @v: the interval value to refer to
 572  *
 573  * Refines the interval value with the reference value.
 574  * The interval is changed to the range satisfying both intervals.
 575  * The interval status (min, max, integer, etc.) are evaluated.
 576  *
 577  * Return: Positive if the value is changed, zero if it's not changed, or a
 578  * negative error code.
 579  */
 580 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
 581 {
 582         int changed = 0;
 583         if (snd_BUG_ON(snd_interval_empty(i)))
 584                 return -EINVAL;
 585         if (i->min < v->min) {
 586                 i->min = v->min;
 587                 i->openmin = v->openmin;
 588                 changed = 1;
 589         } else if (i->min == v->min && !i->openmin && v->openmin) {
 590                 i->openmin = 1;
 591                 changed = 1;
 592         }
 593         if (i->max > v->max) {
 594                 i->max = v->max;
 595                 i->openmax = v->openmax;
 596                 changed = 1;
 597         } else if (i->max == v->max && !i->openmax && v->openmax) {
 598                 i->openmax = 1;
 599                 changed = 1;
 600         }
 601         if (!i->integer && v->integer) {
 602                 i->integer = 1;
 603                 changed = 1;
 604         }
 605         if (i->integer) {
 606                 if (i->openmin) {
 607                         i->min++;
 608                         i->openmin = 0;
 609                 }
 610                 if (i->openmax) {
 611                         i->max--;
 612                         i->openmax = 0;
 613                 }
 614         } else if (!i->openmin && !i->openmax && i->min == i->max)
 615                 i->integer = 1;
 616         if (snd_interval_checkempty(i)) {
 617                 snd_interval_none(i);
 618                 return -EINVAL;
 619         }
 620         return changed;
 621 }
 622 EXPORT_SYMBOL(snd_interval_refine);
 623
 624 static int snd_interval_refine_first(struct snd_interval *i)
 625 {
 626         const unsigned int last_max = i->max;
 627
 628         if (snd_BUG_ON(snd_interval_empty(i)))
 629                 return -EINVAL;
 630         if (snd_interval_single(i))
 631                 return 0;
 632         i->max = i->min;
 633         if (i->openmin)
 634                 i->max++;
 635         /* only exclude max value if also excluded before refine */
 636         i->openmax = (i->openmax && i->max >= last_max);
 637         return 1;
 638 }
 639
 640 static int snd_interval_refine_last(struct snd_interval *i)
 641 {
 642         const unsigned int last_min = i->min;
 643
 644         if (snd_BUG_ON(snd_interval_empty(i)))
 645                 return -EINVAL;
 646         if (snd_interval_single(i))
 647                 return 0;
 648         i->min = i->max;
 649         if (i->openmax)
 650                 i->min--;
 651         /* only exclude min value if also excluded before refine */
 652         i->openmin = (i->openmin && i->min <= last_min);
 653         return 1;
 654 }
 655
 656 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 657 {
 658         if (a->empty || b->empty) {
 659                 snd_interval_none(c);
 660                 return;
 661         }
 662         c->empty = 0;
 663         c->min = mul(a->min, b->min);
 664         c->openmin = (a->openmin || b->openmin);
 665         c->max = mul(a->max,  b->max);
 666         c->openmax = (a->openmax || b->openmax);
 667         c->integer = (a->integer && b->integer);
 668 }
 669
 670 /**
 671  * snd_interval_div - refine the interval value with division
 672  * @a: dividend
 673  * @b: divisor
 674  * @c: quotient
 675  *
 676  * c = a / b
 677  *
 678  * Returns non-zero if the value is changed, zero if not changed.
 679  */
 680 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 681 {
 682         unsigned int r;
 683         if (a->empty || b->empty) {
 684                 snd_interval_none(c);
 685                 return;
 686         }
 687         c->empty = 0;
 688         c->min = div32(a->min, b->max, &r);
 689         c->openmin = (r || a->openmin || b->openmax);
 690         if (b->min > 0) {
 691                 c->max = div32(a->max, b->min, &r);
 692                 if (r) {
 693                         c->max++;
 694                         c->openmax = 1;
 695                 } else
 696                         c->openmax = (a->openmax || b->openmin);
 697         } else {
 698                 c->max = UINT_MAX;
 699                 c->openmax = 0;
 700         }
 701         c->integer = 0;
 702 }
 703
 704 /**
 705  * snd_interval_muldivk - refine the interval value
 706  * @a: dividend 1
 707  * @b: dividend 2
 708  * @k: divisor (as integer)
 709  * @c: result
 710   *
 711  * c = a * b / k
 712  *
 713  * Returns non-zero if the value is changed, zero if not changed.
 714  */
 715 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
 716                       unsigned int k, struct snd_interval *c)
 717 {
 718         unsigned int r;
 719         if (a->empty || b->empty) {
 720                 snd_interval_none(c);
 721                 return;
 722         }
 723         c->empty = 0;
 724         c->min = muldiv32(a->min, b->min, k, &r);
 725         c->openmin = (r || a->openmin || b->openmin);
 726         c->max = muldiv32(a->max, b->max, k, &r);
 727         if (r) {
 728                 c->max++;
 729                 c->openmax = 1;
 730         } else
 731                 c->openmax = (a->openmax || b->openmax);
 732         c->integer = 0;
 733 }
 734
 735 /**
 736  * snd_interval_mulkdiv - refine the interval value
 737  * @a: dividend 1
 738  * @k: dividend 2 (as integer)
 739  * @b: divisor
 740  * @c: result
 741  *
 742  * c = a * k / b
 743  *
 744  * Returns non-zero if the value is changed, zero if not changed.
 745  */
 746 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
 747                       const struct snd_interval *b, struct snd_interval *c)
 748 {
 749         unsigned int r;
 750         if (a->empty || b->empty) {
 751                 snd_interval_none(c);
 752                 return;
 753         }
 754         c->empty = 0;
 755         c->min = muldiv32(a->min, k, b->max, &r);
 756         c->openmin = (r || a->openmin || b->openmax);
 757         if (b->min > 0) {
 758                 c->max = muldiv32(a->max, k, b->min, &r);
 759                 if (r) {
 760                         c->max++;
 761                         c->openmax = 1;
 762                 } else
 763                         c->openmax = (a->openmax || b->openmin);
 764         } else {
 765                 c->max = UINT_MAX;
 766                 c->openmax = 0;
 767         }
 768         c->integer = 0;
 769 }
 770
 771 /* ---- */
 772
 773
 774 /**
 775  * snd_interval_ratnum - refine the interval value
 776  * @i: interval to refine
 777  * @rats_count: number of ratnum_t
 778  * @rats: ratnum_t array
 779  * @nump: pointer to store the resultant numerator
 780  * @denp: pointer to store the resultant denominator
 781  *
 782  * Return: Positive if the value is changed, zero if it's not changed, or a
 783  * negative error code.
 784  */
 785 int snd_interval_ratnum(struct snd_interval *i,
 786                         unsigned int rats_count, const struct snd_ratnum *rats,
 787                         unsigned int *nump, unsigned int *denp)
 788 {
 789         unsigned int best_num, best_den;
 790         int best_diff;
 791         unsigned int k;
 792         struct snd_interval t;
 793         int err;
 794         unsigned int result_num, result_den;
 795         int result_diff;
 796
 797         best_num = best_den = best_diff = 0;
 798         for (k = 0; k < rats_count; ++k) {
 799                 unsigned int num = rats[k].num;
 800                 unsigned int den;
 801                 unsigned int q = i->min;
 802                 int diff;
 803                 if (q == 0)
 804                         q = 1;
 805                 den = div_up(num, q);
 806                 if (den < rats[k].den_min)
 807                         continue;
 808                 if (den > rats[k].den_max)
 809                         den = rats[k].den_max;
 810                 else {
 811                         unsigned int r;
 812                         r = (den - rats[k].den_min) % rats[k].den_step;
 813                         if (r != 0)
 814                                 den -= r;
 815                 }
 816                 diff = num - q * den;
 817                 if (diff < 0)
 818                         diff = -diff;
 819                 if (best_num == 0 ||
 820                     diff * best_den < best_diff * den) {
 821                         best_diff = diff;
 822                         best_den = den;
 823                         best_num = num;
 824                 }
 825         }
 826         if (best_den == 0) {
 827                 i->empty = 1;
 828                 return -EINVAL;
 829         }
 830         t.min = div_down(best_num, best_den);
 831         t.openmin = !!(best_num % best_den);
 832
 833         result_num = best_num;
 834         result_diff = best_diff;
 835         result_den = best_den;
 836         best_num = best_den = best_diff = 0;
 837         for (k = 0; k < rats_count; ++k) {
 838                 unsigned int num = rats[k].num;
 839                 unsigned int den;
 840                 unsigned int q = i->max;
 841                 int diff;
 842                 if (q == 0) {
 843                         i->empty = 1;
 844                         return -EINVAL;
 845                 }
 846                 den = div_down(num, q);
 847                 if (den > rats[k].den_max)
 848                         continue;
 849                 if (den < rats[k].den_min)
 850                         den = rats[k].den_min;
 851                 else {
 852                         unsigned int r;
 853                         r = (den - rats[k].den_min) % rats[k].den_step;
 854                         if (r != 0)
 855                                 den += rats[k].den_step - r;
 856                 }
 857                 diff = q * den - num;
 858                 if (diff < 0)
 859                         diff = -diff;
 860                 if (best_num == 0 ||
 861                     diff * best_den < best_diff * den) {
 862                         best_diff = diff;
 863                         best_den = den;
 864                         best_num = num;
 865                 }
 866         }
 867         if (best_den == 0) {
 868                 i->empty = 1;
 869                 return -EINVAL;
 870         }
 871         t.max = div_up(best_num, best_den);
 872         t.openmax = !!(best_num % best_den);
 873         t.integer = 0;
 874         err = snd_interval_refine(i, &t);
 875         if (err < 0)
 876                 return err;
 877
 878         if (snd_interval_single(i)) {
 879                 if (best_diff * result_den < result_diff * best_den) {
 880                         result_num = best_num;
 881                         result_den = best_den;
 882                 }
 883                 if (nump)
 884                         *nump = result_num;
 885                 if (denp)
 886                         *denp = result_den;
 887         }
 888         return err;
 889 }
 890 EXPORT_SYMBOL(snd_interval_ratnum);
 891
 892 /**
 893  * snd_interval_ratden - refine the interval value
 894  * @i: interval to refine
 895  * @rats_count: number of struct ratden
 896  * @rats: struct ratden array
 897  * @nump: pointer to store the resultant numerator
 898  * @denp: pointer to store the resultant denominator
 899  *
 900  * Return: Positive if the value is changed, zero if it's not changed, or a
 901  * negative error code.
 902  */
 903 static int snd_interval_ratden(struct snd_interval *i,
 904                                unsigned int rats_count,
 905                                const struct snd_ratden *rats,
 906                                unsigned int *nump, unsigned int *denp)
 907 {
 908         unsigned int best_num, best_diff, best_den;
 909         unsigned int k;
 910         struct snd_interval t;
 911         int err;
 912
 913         best_num = best_den = best_diff = 0;
 914         for (k = 0; k < rats_count; ++k) {
 915                 unsigned int num;
 916                 unsigned int den = rats[k].den;
 917                 unsigned int q = i->min;
 918                 int diff;
 919                 num = mul(q, den);
 920                 if (num > rats[k].num_max)
 921                         continue;
 922                 if (num < rats[k].num_min)
 923                         num = rats[k].num_max;
 924                 else {
 925                         unsigned int r;
 926                         r = (num - rats[k].num_min) % rats[k].num_step;
 927                         if (r != 0)
 928                                 num += rats[k].num_step - r;
 929                 }
 930                 diff = num - q * den;
 931                 if (best_num == 0 ||
 932                     diff * best_den < best_diff * den) {
 933                         best_diff = diff;
 934                         best_den = den;
 935                         best_num = num;
 936                 }
 937         }
 938         if (best_den == 0) {
 939                 i->empty = 1;
 940                 return -EINVAL;
 941         }
 942         t.min = div_down(best_num, best_den);
 943         t.openmin = !!(best_num % best_den);
 944
 945         best_num = best_den = best_diff = 0;
 946         for (k = 0; k < rats_count; ++k) {
 947                 unsigned int num;
 948                 unsigned int den = rats[k].den;
 949                 unsigned int q = i->max;
 950                 int diff;
 951                 num = mul(q, den);
 952                 if (num < rats[k].num_min)
 953                         continue;
 954                 if (num > rats[k].num_max)
 955                         num = rats[k].num_max;
 956                 else {
 957                         unsigned int r;
 958                         r = (num - rats[k].num_min) % rats[k].num_step;
 959                         if (r != 0)
 960                                 num -= r;
 961                 }
 962                 diff = q * den - num;
 963                 if (best_num == 0 ||
 964                     diff * best_den < best_diff * den) {
 965                         best_diff = diff;
 966                         best_den = den;
 967                         best_num = num;
 968                 }
 969         }
 970         if (best_den == 0) {
 971                 i->empty = 1;
 972                 return -EINVAL;
 973         }
 974         t.max = div_up(best_num, best_den);
 975         t.openmax = !!(best_num % best_den);
 976         t.integer = 0;
 977         err = snd_interval_refine(i, &t);
 978         if (err < 0)
 979                 return err;
 980
 981         if (snd_interval_single(i)) {
 982                 if (nump)
 983                         *nump = best_num;
 984                 if (denp)
 985                         *denp = best_den;
 986         }
 987         return err;
 988 }
 989
 990 /**
 991  * snd_interval_list - refine the interval value from the list
 992  * @i: the interval value to refine
 993  * @count: the number of elements in the list
 994  * @list: the value list
 995  * @mask: the bit-mask to evaluate
 996  *
 997  * Refines the interval value from the list.
 998  * When mask is non-zero, only the elements corresponding to bit 1 are
 999  * evaluated.
1000  *
1001  * Return: Positive if the value is changed, zero if it's not changed, or a
1002  * negative error code.
1003  */
1004 int snd_interval_list(struct snd_interval *i, unsigned int count,
1005                       const unsigned int *list, unsigned int mask)
1006 {
1007         unsigned int k;
1008         struct snd_interval list_range;
1009
1010         if (!count) {
1011                 i->empty = 1;
1012                 return -EINVAL;
1013         }
1014         snd_interval_any(&list_range);
1015         list_range.min = UINT_MAX;
1016         list_range.max = 0;
1017         for (k = 0; k < count; k++) {
1018                 if (mask && !(mask & (1 << k)))
1019                         continue;
1020                 if (!snd_interval_test(i, list[k]))
1021                         continue;
1022                 list_range.min = min(list_range.min, list[k]);
1023                 list_range.max = max(list_range.max, list[k]);
1024         }
1025         return snd_interval_refine(i, &list_range);
1026 }
1027 EXPORT_SYMBOL(snd_interval_list);
1028
1029 /**
1030  * snd_interval_ranges - refine the interval value from the list of ranges
1031  * @i: the interval value to refine
1032  * @count: the number of elements in the list of ranges
1033  * @ranges: the ranges list
1034  * @mask: the bit-mask to evaluate
1035  *
1036  * Refines the interval value from the list of ranges.
1037  * When mask is non-zero, only the elements corresponding to bit 1 are
1038  * evaluated.
1039  *
1040  * Return: Positive if the value is changed, zero if it's not changed, or a
1041  * negative error code.
1042  */
1043 int snd_interval_ranges(struct snd_interval *i, unsigned int count,
1044                         const struct snd_interval *ranges, unsigned int mask)
1045 {
1046         unsigned int k;
1047         struct snd_interval range_union;
1048         struct snd_interval range;
1049
1050         if (!count) {
1051                 snd_interval_none(i);
1052                 return -EINVAL;
1053         }
1054         snd_interval_any(&range_union);
1055         range_union.min = UINT_MAX;
1056         range_union.max = 0;
1057         for (k = 0; k < count; k++) {
1058                 if (mask && !(mask & (1 << k)))
1059                         continue;
1060                 snd_interval_copy(&range, &ranges[k]);
1061                 if (snd_interval_refine(&range, i) < 0)
1062                         continue;
1063                 if (snd_interval_empty(&range))
1064                         continue;
1065
1066                 if (range.min < range_union.min) {
1067                         range_union.min = range.min;
1068                         range_union.openmin = 1;
1069                 }
1070                 if (range.min == range_union.min && !range.openmin)
1071                         range_union.openmin = 0;
1072                 if (range.max > range_union.max) {
1073                         range_union.max = range.max;
1074                         range_union.openmax = 1;
1075                 }
1076                 if (range.max == range_union.max && !range.openmax)
1077                         range_union.openmax = 0;
1078         }
1079         return snd_interval_refine(i, &range_union);
1080 }
1081 EXPORT_SYMBOL(snd_interval_ranges);
1082
1083 static int snd_interval_step(struct snd_interval *i, unsigned int step)
1084 {
1085         unsigned int n;
1086         int changed = 0;
1087         n = i->min % step;
1088         if (n != 0 || i->openmin) {
1089                 i->min += step - n;
1090                 i->openmin = 0;
1091                 changed = 1;
1092         }
1093         n = i->max % step;
1094         if (n != 0 || i->openmax) {
1095                 i->max -= n;
1096                 i->openmax = 0;
1097                 changed = 1;
1098         }
1099         if (snd_interval_checkempty(i)) {
1100                 i->empty = 1;
1101                 return -EINVAL;
1102         }
1103         return changed;
1104 }
1105
1106 /* Info constraints helpers */
1107
1108 /**
1109  * snd_pcm_hw_rule_add - add the hw-constraint rule
1110  * @runtime: the pcm runtime instance
1111  * @cond: condition bits
1112  * @var: the variable to evaluate
1113  * @func: the evaluation function
1114  * @private: the private data pointer passed to function
1115  * @dep: the dependent variables
1116  *
1117  * Return: Zero if successful, or a negative error code on failure.
1118  */
1119 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1120                         int var,
1121                         snd_pcm_hw_rule_func_t func, void *private,
1122                         int dep, ...)
1123 {
1124         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1125         struct snd_pcm_hw_rule *c;
1126         unsigned int k;
1127         va_list args;
1128         va_start(args, dep);
1129         if (constrs->rules_num >= constrs->rules_all) {
1130                 struct snd_pcm_hw_rule *new;
1131                 unsigned int new_rules = constrs->rules_all + 16;
1132                 new = krealloc_array(constrs->rules, new_rules,
1133                                      sizeof(*c), GFP_KERNEL);
1134                 if (!new) {
1135                         va_end(args);
1136                         return -ENOMEM;
1137                 }
1138                 constrs->rules = new;
1139                 constrs->rules_all = new_rules;
1140         }
1141         c = &constrs->rules[constrs->rules_num];
1142         c->cond = cond;
1143         c->func = func;
1144         c->var = var;
1145         c->private = private;
1146         k = 0;
1147         while (1) {
1148                 if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1149                         va_end(args);
1150                         return -EINVAL;
1151                 }
1152                 c->deps[k++] = dep;
1153                 if (dep < 0)
1154                         break;
1155                 dep = va_arg(args, int);
1156         }
1157         constrs->rules_num++;
1158         va_end(args);
1159         return 0;
1160 }
1161 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1162
1163 /**
1164  * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1165  * @runtime: PCM runtime instance
1166  * @var: hw_params variable to apply the mask
1167  * @mask: the bitmap mask
1168  *
1169  * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1170  *
1171  * Return: Zero if successful, or a negative error code on failure.
1172  */
1173 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1174                                u_int32_t mask)
1175 {
1176         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1177         struct snd_mask *maskp = constrs_mask(constrs, var);
1178         *maskp->bits &= mask;
1179         memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1180         if (*maskp->bits == 0)
1181                 return -EINVAL;
1182         return 0;
1183 }
1184
1185 /**
1186  * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1187  * @runtime: PCM runtime instance
1188  * @var: hw_params variable to apply the mask
1189  * @mask: the 64bit bitmap mask
1190  *
1191  * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1192  *
1193  * Return: Zero if successful, or a negative error code on failure.
1194  */
1195 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1196                                  u_int64_t mask)
1197 {
1198         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1199         struct snd_mask *maskp = constrs_mask(constrs, var);
1200         maskp->bits[0] &= (u_int32_t)mask;
1201         maskp->bits[1] &= (u_int32_t)(mask >> 32);
1202         memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1203         if (! maskp->bits[0] && ! maskp->bits[1])
1204                 return -EINVAL;
1205         return 0;
1206 }
1207 EXPORT_SYMBOL(snd_pcm_hw_constraint_mask64);
1208
1209 /**
1210  * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1211  * @runtime: PCM runtime instance
1212  * @var: hw_params variable to apply the integer constraint
1213  *
1214  * Apply the constraint of integer to an interval parameter.
1215  *
1216  * Return: Positive if the value is changed, zero if it's not changed, or a
1217  * negative error code.
1218  */
1219 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1220 {
1221         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1222         return snd_interval_setinteger(constrs_interval(constrs, var));
1223 }
1224 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1225
1226 /**
1227  * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1228  * @runtime: PCM runtime instance
1229  * @var: hw_params variable to apply the range
1230  * @min: the minimal value
1231  * @max: the maximal value
1232  *
1233  * Apply the min/max range constraint to an interval parameter.
1234  *
1235  * Return: Positive if the value is changed, zero if it's not changed, or a
1236  * negative error code.
1237  */
1238 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1239                                  unsigned int min, unsigned int max)
1240 {
1241         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1242         struct snd_interval t;
1243         t.min = min;
1244         t.max = max;
1245         t.openmin = t.openmax = 0;
1246         t.integer = 0;
1247         return snd_interval_refine(constrs_interval(constrs, var), &t);
1248 }
1249 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1250
1251 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1252                                 struct snd_pcm_hw_rule *rule)
1253 {
1254         struct snd_pcm_hw_constraint_list *list = rule->private;
1255         return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1256 }
1257
1258
1259 /**
1260  * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1261  * @runtime: PCM runtime instance
1262  * @cond: condition bits
1263  * @var: hw_params variable to apply the list constraint
1264  * @l: list
1265  *
1266  * Apply the list of constraints to an interval parameter.
1267  *
1268  * Return: Zero if successful, or a negative error code on failure.
1269  */
1270 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1271                                unsigned int cond,
1272                                snd_pcm_hw_param_t var,
1273                                const struct snd_pcm_hw_constraint_list *l)
1274 {
1275         return snd_pcm_hw_rule_add(runtime, cond, var,
1276                                    snd_pcm_hw_rule_list, (void *)l,
1277                                    var, -1);
1278 }
1279 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1280
1281 static int snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params *params,
1282                                   struct snd_pcm_hw_rule *rule)
1283 {
1284         struct snd_pcm_hw_constraint_ranges *r = rule->private;
1285         return snd_interval_ranges(hw_param_interval(params, rule->var),
1286                                    r->count, r->ranges, r->mask);
1287 }
1288
1289
1290 /**
1291  * snd_pcm_hw_constraint_ranges - apply list of range constraints to a parameter
1292  * @runtime: PCM runtime instance
1293  * @cond: condition bits
1294  * @var: hw_params variable to apply the list of range constraints
1295  * @r: ranges
1296  *
1297  * Apply the list of range constraints to an interval parameter.
1298  *
1299  * Return: Zero if successful, or a negative error code on failure.
1300  */
1301 int snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime *runtime,
1302                                  unsigned int cond,
1303                                  snd_pcm_hw_param_t var,
1304                                  const struct snd_pcm_hw_constraint_ranges *r)
1305 {
1306         return snd_pcm_hw_rule_add(runtime, cond, var,
1307                                    snd_pcm_hw_rule_ranges, (void *)r,
1308                                    var, -1);
1309 }
1310 EXPORT_SYMBOL(snd_pcm_hw_constraint_ranges);
1311
1312 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1313                                    struct snd_pcm_hw_rule *rule)
1314 {
1315         const struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1316         unsigned int num = 0, den = 0;
1317         int err;
1318         err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1319                                   r->nrats, r->rats, &num, &den);
1320         if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1321                 params->rate_num = num;
1322                 params->rate_den = den;
1323         }
1324         return err;
1325 }
1326
1327 /**
1328  * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1329  * @runtime: PCM runtime instance
1330  * @cond: condition bits
1331  * @var: hw_params variable to apply the ratnums constraint
1332  * @r: struct snd_ratnums constriants
1333  *
1334  * Return: Zero if successful, or a negative error code on failure.
1335  */
1336 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1337                                   unsigned int cond,
1338                                   snd_pcm_hw_param_t var,
1339                                   const struct snd_pcm_hw_constraint_ratnums *r)
1340 {
1341         return snd_pcm_hw_rule_add(runtime, cond, var,
1342                                    snd_pcm_hw_rule_ratnums, (void *)r,
1343                                    var, -1);
1344 }
1345 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1346
1347 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1348                                    struct snd_pcm_hw_rule *rule)
1349 {
1350         const struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1351         unsigned int num = 0, den = 0;
1352         int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1353                                   r->nrats, r->rats, &num, &den);
1354         if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1355                 params->rate_num = num;
1356                 params->rate_den = den;
1357         }
1358         return err;
1359 }
1360
1361 /**
1362  * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1363  * @runtime: PCM runtime instance
1364  * @cond: condition bits
1365  * @var: hw_params variable to apply the ratdens constraint
1366  * @r: struct snd_ratdens constriants
1367  *
1368  * Return: Zero if successful, or a negative error code on failure.
1369  */
1370 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1371                                   unsigned int cond,
1372                                   snd_pcm_hw_param_t var,
1373                                   const struct snd_pcm_hw_constraint_ratdens *r)
1374 {
1375         return snd_pcm_hw_rule_add(runtime, cond, var,
1376                                    snd_pcm_hw_rule_ratdens, (void *)r,
1377                                    var, -1);
1378 }
1379 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1380
1381 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1382                                   struct snd_pcm_hw_rule *rule)
1383 {
1384         unsigned int l = (unsigned long) rule->private;
1385         int width = l & 0xffff;
1386         unsigned int msbits = l >> 16;
1387         const struct snd_interval *i =
1388                 hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1389
1390         if (!snd_interval_single(i))
1391                 return 0;
1392
1393         if ((snd_interval_value(i) == width) ||
1394             (width == 0 && snd_interval_value(i) > msbits))
1395                 params->msbits = min_not_zero(params->msbits, msbits);
1396
1397         return 0;
1398 }
1399
1400 /**
1401  * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1402  * @runtime: PCM runtime instance
1403  * @cond: condition bits
1404  * @width: sample bits width
1405  * @msbits: msbits width
1406  *
1407  * This constraint will set the number of most significant bits (msbits) if a
1408  * sample format with the specified width has been select. If width is set to 0
1409  * the msbits will be set for any sample format with a width larger than the
1410  * specified msbits.
1411  *
1412  * Return: Zero if successful, or a negative error code on failure.
1413  */
1414 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1415                                  unsigned int cond,
1416                                  unsigned int width,
1417                                  unsigned int msbits)
1418 {
1419         unsigned long l = (msbits << 16) | width;
1420         return snd_pcm_hw_rule_add(runtime, cond, -1,
1421                                     snd_pcm_hw_rule_msbits,
1422                                     (void*) l,
1423                                     SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1424 }
1425 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1426
1427 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1428                                 struct snd_pcm_hw_rule *rule)
1429 {
1430         unsigned long step = (unsigned long) rule->private;
1431         return snd_interval_step(hw_param_interval(params, rule->var), step);
1432 }
1433
1434 /**
1435  * snd_pcm_hw_constraint_step - add a hw constraint step rule
1436  * @runtime: PCM runtime instance
1437  * @cond: condition bits
1438  * @var: hw_params variable to apply the step constraint
1439  * @step: step size
1440  *
1441  * Return: Zero if successful, or a negative error code on failure.
1442  */
1443 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1444                                unsigned int cond,
1445                                snd_pcm_hw_param_t var,
1446                                unsigned long step)
1447 {
1448         return snd_pcm_hw_rule_add(runtime, cond, var,
1449                                    snd_pcm_hw_rule_step, (void *) step,
1450                                    var, -1);
1451 }
1452 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1453
1454 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1455 {
1456         static const unsigned int pow2_sizes[] = {
1457                 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1458                 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1459                 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1460                 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1461         };
1462         return snd_interval_list(hw_param_interval(params, rule->var),
1463                                  ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1464 }
1465
1466 /**
1467  * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1468  * @runtime: PCM runtime instance
1469  * @cond: condition bits
1470  * @var: hw_params variable to apply the power-of-2 constraint
1471  *
1472  * Return: Zero if successful, or a negative error code on failure.
1473  */
1474 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1475                                unsigned int cond,
1476                                snd_pcm_hw_param_t var)
1477 {
1478         return snd_pcm_hw_rule_add(runtime, cond, var,
1479                                    snd_pcm_hw_rule_pow2, NULL,
1480                                    var, -1);
1481 }
1482 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1483
1484 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1485                                            struct snd_pcm_hw_rule *rule)
1486 {
1487         unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1488         struct snd_interval *rate;
1489
1490         rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1491         return snd_interval_list(rate, 1, &base_rate, 0);
1492 }
1493
1494 /**
1495  * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1496  * @runtime: PCM runtime instance
1497  * @base_rate: the rate at which the hardware does not resample
1498  *
1499  * Return: Zero if successful, or a negative error code on failure.
1500  */
1501 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1502                                unsigned int base_rate)
1503 {
1504         return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1505                                    SNDRV_PCM_HW_PARAM_RATE,
1506                                    snd_pcm_hw_rule_noresample_func,
1507                                    (void *)(uintptr_t)base_rate,
1508                                    SNDRV_PCM_HW_PARAM_RATE, -1);
1509 }
1510 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1511
1512 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1513                                   snd_pcm_hw_param_t var)
1514 {
1515         if (hw_is_mask(var)) {
1516                 snd_mask_any(hw_param_mask(params, var));
1517                 params->cmask |= 1 << var;
1518                 params->rmask |= 1 << var;
1519                 return;
1520         }
1521         if (hw_is_interval(var)) {
1522                 snd_interval_any(hw_param_interval(params, var));
1523                 params->cmask |= 1 << var;
1524                 params->rmask |= 1 << var;
1525                 return;
1526         }
1527         snd_BUG();
1528 }
1529
1530 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1531 {
1532         unsigned int k;
1533         memset(params, 0, sizeof(*params));
1534         for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1535                 _snd_pcm_hw_param_any(params, k);
1536         for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1537                 _snd_pcm_hw_param_any(params, k);
1538         params->info = ~0U;
1539 }
1540 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1541
1542 /**
1543  * snd_pcm_hw_param_value - return @params field @var value
1544  * @params: the hw_params instance
1545  * @var: parameter to retrieve
1546  * @dir: pointer to the direction (-1,0,1) or %NULL
1547  *
1548  * Return: The value for field @var if it's fixed in configuration space
1549  * defined by @params. -%EINVAL otherwise.
1550  */
1551 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1552                            snd_pcm_hw_param_t var, int *dir)
1553 {
1554         if (hw_is_mask(var)) {
1555                 const struct snd_mask *mask = hw_param_mask_c(params, var);
1556                 if (!snd_mask_single(mask))
1557                         return -EINVAL;
1558                 if (dir)
1559                         *dir = 0;
1560                 return snd_mask_value(mask);
1561         }
1562         if (hw_is_interval(var)) {
1563                 const struct snd_interval *i = hw_param_interval_c(params, var);
1564                 if (!snd_interval_single(i))
1565                         return -EINVAL;
1566                 if (dir)
1567                         *dir = i->openmin;
1568                 return snd_interval_value(i);
1569         }
1570         return -EINVAL;
1571 }
1572 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1573
1574 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1575                                 snd_pcm_hw_param_t var)
1576 {
1577         if (hw_is_mask(var)) {
1578                 snd_mask_none(hw_param_mask(params, var));
1579                 params->cmask |= 1 << var;
1580                 params->rmask |= 1 << var;
1581         } else if (hw_is_interval(var)) {
1582                 snd_interval_none(hw_param_interval(params, var));
1583                 params->cmask |= 1 << var;
1584                 params->rmask |= 1 << var;
1585         } else {
1586                 snd_BUG();
1587         }
1588 }
1589 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1590
1591 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1592                                    snd_pcm_hw_param_t var)
1593 {
1594         int changed;
1595         if (hw_is_mask(var))
1596                 changed = snd_mask_refine_first(hw_param_mask(params, var));
1597         else if (hw_is_interval(var))
1598                 changed = snd_interval_refine_first(hw_param_interval(params, var));
1599         else
1600                 return -EINVAL;
1601         if (changed > 0) {
1602                 params->cmask |= 1 << var;
1603                 params->rmask |= 1 << var;
1604         }
1605         return changed;
1606 }
1607
1608
1609 /**
1610  * snd_pcm_hw_param_first - refine config space and return minimum value
1611  * @pcm: PCM instance
1612  * @params: the hw_params instance
1613  * @var: parameter to retrieve
1614  * @dir: pointer to the direction (-1,0,1) or %NULL
1615  *
1616  * Inside configuration space defined by @params remove from @var all
1617  * values > minimum. Reduce configuration space accordingly.
1618  *
1619  * Return: The minimum, or a negative error code on failure.
1620  */
1621 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1622                            struct snd_pcm_hw_params *params,
1623                            snd_pcm_hw_param_t var, int *dir)
1624 {
1625         int changed = _snd_pcm_hw_param_first(params, var);
1626         if (changed < 0)
1627                 return changed;
1628         if (params->rmask) {
1629                 int err = snd_pcm_hw_refine(pcm, params);
1630                 if (err < 0)
1631                         return err;
1632         }
1633         return snd_pcm_hw_param_value(params, var, dir);
1634 }
1635 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1636
1637 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1638                                   snd_pcm_hw_param_t var)
1639 {
1640         int changed;
1641         if (hw_is_mask(var))
1642                 changed = snd_mask_refine_last(hw_param_mask(params, var));
1643         else if (hw_is_interval(var))
1644                 changed = snd_interval_refine_last(hw_param_interval(params, var));
1645         else
1646                 return -EINVAL;
1647         if (changed > 0) {
1648                 params->cmask |= 1 << var;
1649                 params->rmask |= 1 << var;
1650         }
1651         return changed;
1652 }
1653
1654
1655 /**
1656  * snd_pcm_hw_param_last - refine config space and return maximum value
1657  * @pcm: PCM instance
1658  * @params: the hw_params instance
1659  * @var: parameter to retrieve
1660  * @dir: pointer to the direction (-1,0,1) or %NULL
1661  *
1662  * Inside configuration space defined by @params remove from @var all
1663  * values < maximum. Reduce configuration space accordingly.
1664  *
1665  * Return: The maximum, or a negative error code on failure.
1666  */
1667 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1668                           struct snd_pcm_hw_params *params,
1669                           snd_pcm_hw_param_t var, int *dir)
1670 {
1671         int changed = _snd_pcm_hw_param_last(params, var);
1672         if (changed < 0)
1673                 return changed;
1674         if (params->rmask) {
1675                 int err = snd_pcm_hw_refine(pcm, params);
1676                 if (err < 0)
1677                         return err;
1678         }
1679         return snd_pcm_hw_param_value(params, var, dir);
1680 }
1681 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1682
1683 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1684                                    void *arg)
1685 {
1686         struct snd_pcm_runtime *runtime = substream->runtime;
1687         unsigned long flags;
1688         snd_pcm_stream_lock_irqsave(substream, flags);
1689         if (snd_pcm_running(substream) &&
1690             snd_pcm_update_hw_ptr(substream) >= 0)
1691                 runtime->status->hw_ptr %= runtime->buffer_size;
1692         else {
1693                 runtime->status->hw_ptr = 0;
1694                 runtime->hw_ptr_wrap = 0;
1695         }
1696         snd_pcm_stream_unlock_irqrestore(substream, flags);
1697         return 0;
1698 }
1699
1700 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1701                                           void *arg)
1702 {
1703         struct snd_pcm_channel_info *info = arg;
1704         struct snd_pcm_runtime *runtime = substream->runtime;
1705         int width;
1706         if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1707                 info->offset = -1;
1708                 return 0;
1709         }
1710         width = snd_pcm_format_physical_width(runtime->format);
1711         if (width < 0)
1712                 return width;
1713         info->offset = 0;
1714         switch (runtime->access) {
1715         case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1716         case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1717                 info->first = info->channel * width;
1718                 info->step = runtime->channels * width;
1719                 break;
1720         case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1721         case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1722         {
1723                 size_t size = runtime->dma_bytes / runtime->channels;
1724                 info->first = info->channel * size * 8;
1725                 info->step = width;
1726                 break;
1727         }
1728         default:
1729                 snd_BUG();
1730                 break;
1731         }
1732         return 0;
1733 }
1734
1735 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1736                                        void *arg)
1737 {
1738         struct snd_pcm_hw_params *params = arg;
1739         snd_pcm_format_t format;
1740         int channels;
1741         ssize_t frame_size;
1742
1743         params->fifo_size = substream->runtime->hw.fifo_size;
1744         if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1745                 format = params_format(params);
1746                 channels = params_channels(params);
1747                 frame_size = snd_pcm_format_size(format, channels);
1748                 if (frame_size > 0)
1749                         params->fifo_size /= frame_size;
1750         }
1751         return 0;
1752 }
1753
1754 /**
1755  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1756  * @substream: the pcm substream instance
1757  * @cmd: ioctl command
1758  * @arg: ioctl argument
1759  *
1760  * Processes the generic ioctl commands for PCM.
1761  * Can be passed as the ioctl callback for PCM ops.
1762  *
1763  * Return: Zero if successful, or a negative error code on failure.
1764  */
1765 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1766                       unsigned int cmd, void *arg)
1767 {
1768         switch (cmd) {
1769         case SNDRV_PCM_IOCTL1_RESET:
1770                 return snd_pcm_lib_ioctl_reset(substream, arg);
1771         case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1772                 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1773         case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1774                 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1775         }
1776         return -ENXIO;
1777 }
1778 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1779
1780 /**
1781  * snd_pcm_period_elapsed_under_stream_lock() - update the status of runtime for the next period
1782  *                                              under acquired lock of PCM substream.
1783  * @substream: the instance of pcm substream.
1784  *
1785  * This function is called when the batch of audio data frames as the same size as the period of
1786  * buffer is already processed in audio data transmission.
1787  *
1788  * The call of function updates the status of runtime with the latest position of audio data
1789  * transmission, checks overrun and underrun over buffer, awaken user processes from waiting for
1790  * available audio data frames, sampling audio timestamp, and performs stop or drain the PCM
1791  * substream according to configured threshold.
1792  *
1793  * The function is intended to use for the case that PCM driver operates audio data frames under
1794  * acquired lock of PCM substream; e.g. in callback of any operation of &snd_pcm_ops in process
1795  * context. In any interrupt context, it's preferrable to use ``snd_pcm_period_elapsed()`` instead
1796  * since lock of PCM substream should be acquired in advance.
1797  *
1798  * Developer should pay enough attention that some callbacks in &snd_pcm_ops are done by the call of
1799  * function:
1800  *
1801  * - .pointer - to retrieve current position of audio data transmission by frame count or XRUN state.
1802  * - .trigger - with SNDRV_PCM_TRIGGER_STOP at XRUN or DRAINING state.
1803  * - .get_time_info - to retrieve audio time stamp if needed.
1804  *
1805  * Even if more than one periods have elapsed since the last call, you have to call this only once.
1806  */
1807 void snd_pcm_period_elapsed_under_stream_lock(struct snd_pcm_substream *substream)
1808 {
1809         struct snd_pcm_runtime *runtime;
1810
1811         if (PCM_RUNTIME_CHECK(substream))
1812                 return;
1813         runtime = substream->runtime;
1814
1815         if (!snd_pcm_running(substream) ||
1816             snd_pcm_update_hw_ptr0(substream, 1) < 0)
1817                 goto _end;
1818
1819 #ifdef CONFIG_SND_PCM_TIMER
1820         if (substream->timer_running)
1821                 snd_timer_interrupt(substream->timer, 1);
1822 #endif
1823  _end:
1824         kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1825 }
1826 EXPORT_SYMBOL(snd_pcm_period_elapsed_under_stream_lock);
1827
1828 /**
1829  * snd_pcm_period_elapsed() - update the status of runtime for the next period by acquiring lock of
1830  *                            PCM substream.
1831  * @substream: the instance of PCM substream.
1832  *
1833  * This function is mostly similar to ``snd_pcm_period_elapsed_under_stream_lock()`` except for
1834  * acquiring lock of PCM substream voluntarily.
1835  *
1836  * It's typically called by any type of IRQ handler when hardware IRQ occurs to notify event that
1837  * the batch of audio data frames as the same size as the period of buffer is already processed in
1838  * audio data transmission.
1839  */
1840 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1841 {
1842         unsigned long flags;
1843
1844         if (snd_BUG_ON(!substream))
1845                 return;
1846
1847         snd_pcm_stream_lock_irqsave(substream, flags);
1848         snd_pcm_period_elapsed_under_stream_lock(substream);
1849         snd_pcm_stream_unlock_irqrestore(substream, flags);
1850 }
1851 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1852
1853 /*
1854  * Wait until avail_min data becomes available
1855  * Returns a negative error code if any error occurs during operation.
1856  * The available space is stored on availp.  When err = 0 and avail = 0
1857  * on the capture stream, it indicates the stream is in DRAINING state.
1858  */
1859 static int wait_for_avail(struct snd_pcm_substream *substream,
1860                               snd_pcm_uframes_t *availp)
1861 {
1862         struct snd_pcm_runtime *runtime = substream->runtime;
1863         int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1864         wait_queue_entry_t wait;
1865         int err = 0;
1866         snd_pcm_uframes_t avail = 0;
1867         long wait_time, tout;
1868
1869         init_waitqueue_entry(&wait, current);
1870         set_current_state(TASK_INTERRUPTIBLE);
1871         add_wait_queue(&runtime->tsleep, &wait);
1872
1873         if (runtime->no_period_wakeup)
1874                 wait_time = MAX_SCHEDULE_TIMEOUT;
1875         else {
1876                 /* use wait time from substream if available */
1877                 if (substream->wait_time) {
1878                         wait_time = substream->wait_time;
1879                 } else {
1880                         wait_time = 10;
1881
1882                         if (runtime->rate) {
1883                                 long t = runtime->period_size * 2 /
1884                                          runtime->rate;
1885                                 wait_time = max(t, wait_time);
1886                         }
1887                         wait_time = msecs_to_jiffies(wait_time * 1000);
1888                 }
1889         }
1890
1891         for (;;) {
1892                 if (signal_pending(current)) {
1893                         err = -ERESTARTSYS;
1894                         break;
1895                 }
1896
1897                 /*
1898                  * We need to check if space became available already
1899                  * (and thus the wakeup happened already) first to close
1900                  * the race of space already having become available.
1901                  * This check must happen after been added to the waitqueue
1902                  * and having current state be INTERRUPTIBLE.
1903                  */
1904                 avail = snd_pcm_avail(substream);
1905                 if (avail >= runtime->twake)
1906                         break;
1907                 snd_pcm_stream_unlock_irq(substream);
1908
1909                 tout = schedule_timeout(wait_time);
1910
1911                 snd_pcm_stream_lock_irq(substream);
1912                 set_current_state(TASK_INTERRUPTIBLE);
1913                 switch (runtime->status->state) {
1914                 case SNDRV_PCM_STATE_SUSPENDED:
1915                         err = -ESTRPIPE;
1916                         goto _endloop;
1917                 case SNDRV_PCM_STATE_XRUN:
1918                         err = -EPIPE;
1919                         goto _endloop;
1920                 case SNDRV_PCM_STATE_DRAINING:
1921                         if (is_playback)
1922                                 err = -EPIPE;
1923                         else
1924                                 avail = 0; /* indicate draining */
1925                         goto _endloop;
1926                 case SNDRV_PCM_STATE_OPEN:
1927                 case SNDRV_PCM_STATE_SETUP:
1928                 case SNDRV_PCM_STATE_DISCONNECTED:
1929                         err = -EBADFD;
1930                         goto _endloop;
1931                 case SNDRV_PCM_STATE_PAUSED:
1932                         continue;
1933                 }
1934                 if (!tout) {
1935                         pcm_dbg(substream->pcm,
1936                                 "%s write error (DMA or IRQ trouble?)\n",
1937                                 is_playback ? "playback" : "capture");
1938                         err = -EIO;
1939                         break;
1940                 }
1941         }
1942  _endloop:
1943         set_current_state(TASK_RUNNING);
1944         remove_wait_queue(&runtime->tsleep, &wait);
1945         *availp = avail;
1946         return err;
1947 }
1948
1949 typedef int (*pcm_transfer_f)(struct snd_pcm_substream *substream,
1950                               int channel, unsigned long hwoff,
1951                               void *buf, unsigned long bytes);
1952
1953 typedef int (*pcm_copy_f)(struct snd_pcm_substream *, snd_pcm_uframes_t, void *,
1954                           snd_pcm_uframes_t, snd_pcm_uframes_t, pcm_transfer_f);
1955
1956 /* calculate the target DMA-buffer position to be written/read */
1957 static void *get_dma_ptr(struct snd_pcm_runtime *runtime,
1958                            int channel, unsigned long hwoff)
1959 {
1960         return runtime->dma_area + hwoff +
1961                 channel * (runtime->dma_bytes / runtime->channels);
1962 }
1963
1964 /* default copy_user ops for write; used for both interleaved and non- modes */
1965 static int default_write_copy(struct snd_pcm_substream *substream,
1966                               int channel, unsigned long hwoff,
1967                               void *buf, unsigned long bytes)
1968 {
1969         if (copy_from_user(get_dma_ptr(substream->runtime, channel, hwoff),
1970                            (void __user *)buf, bytes))
1971                 return -EFAULT;
1972         return 0;
1973 }
1974
1975 /* default copy_kernel ops for write */
1976 static int default_write_copy_kernel(struct snd_pcm_substream *substream,
1977                                      int channel, unsigned long hwoff,
1978                                      void *buf, unsigned long bytes)
1979 {
1980         memcpy(get_dma_ptr(substream->runtime, channel, hwoff), buf, bytes);
1981         return 0;
1982 }
1983
1984 /* fill silence instead of copy data; called as a transfer helper
1985  * from __snd_pcm_lib_write() or directly from noninterleaved_copy() when
1986  * a NULL buffer is passed
1987  */
1988 static int fill_silence(struct snd_pcm_substream *substream, int channel,
1989                         unsigned long hwoff, void *buf, unsigned long bytes)
1990 {
1991         struct snd_pcm_runtime *runtime = substream->runtime;
1992
1993         if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
1994                 return 0;
1995         if (substream->ops->fill_silence)
1996                 return substream->ops->fill_silence(substream, channel,
1997                                                     hwoff, bytes);
1998
1999         snd_pcm_format_set_silence(runtime->format,
2000                                    get_dma_ptr(runtime, channel, hwoff),
2001                                    bytes_to_samples(runtime, bytes));
2002         return 0;
2003 }
2004
2005 /* default copy_user ops for read; used for both interleaved and non- modes */
2006 static int default_read_copy(struct snd_pcm_substream *substream,
2007                              int channel, unsigned long hwoff,
2008                              void *buf, unsigned long bytes)
2009 {
2010         if (copy_to_user((void __user *)buf,
2011                          get_dma_ptr(substream->runtime, channel, hwoff),
2012                          bytes))
2013                 return -EFAULT;
2014         return 0;
2015 }
2016
2017 /* default copy_kernel ops for read */
2018 static int default_read_copy_kernel(struct snd_pcm_substream *substream,
2019                                     int channel, unsigned long hwoff,
2020                                     void *buf, unsigned long bytes)
2021 {
2022         memcpy(buf, get_dma_ptr(substream->runtime, channel, hwoff), bytes);
2023         return 0;
2024 }
2025
2026 /* call transfer function with the converted pointers and sizes;
2027  * for interleaved mode, it's one shot for all samples
2028  */
2029 static int interleaved_copy(struct snd_pcm_substream *substream,
2030                             snd_pcm_uframes_t hwoff, void *data,
2031                             snd_pcm_uframes_t off,
2032                             snd_pcm_uframes_t frames,
2033                             pcm_transfer_f transfer)
2034 {
2035         struct snd_pcm_runtime *runtime = substream->runtime;
2036
2037         /* convert to bytes */
2038         hwoff = frames_to_bytes(runtime, hwoff);
2039         off = frames_to_bytes(runtime, off);
2040         frames = frames_to_bytes(runtime, frames);
2041         return transfer(substream, 0, hwoff, data + off, frames);
2042 }
2043
2044 /* call transfer function with the converted pointers and sizes for each
2045  * non-interleaved channel; when buffer is NULL, silencing instead of copying
2046  */
2047 static int noninterleaved_copy(struct snd_pcm_substream *substream,
2048                                snd_pcm_uframes_t hwoff, void *data,
2049                                snd_pcm_uframes_t off,
2050                                snd_pcm_uframes_t frames,
2051                                pcm_transfer_f transfer)
2052 {
2053         struct snd_pcm_runtime *runtime = substream->runtime;
2054         int channels = runtime->channels;
2055         void **bufs = data;
2056         int c, err;
2057
2058         /* convert to bytes; note that it's not frames_to_bytes() here.
2059          * in non-interleaved mode, we copy for each channel, thus
2060          * each copy is n_samples bytes x channels = whole frames.
2061          */
2062         off = samples_to_bytes(runtime, off);
2063         frames = samples_to_bytes(runtime, frames);
2064         hwoff = samples_to_bytes(runtime, hwoff);
2065         for (c = 0; c < channels; ++c, ++bufs) {
2066                 if (!data || !*bufs)
2067                         err = fill_silence(substream, c, hwoff, NULL, frames);
2068                 else
2069                         err = transfer(substream, c, hwoff, *bufs + off,
2070                                        frames);
2071                 if (err < 0)
2072                         return err;
2073         }
2074         return 0;
2075 }
2076
2077 /* fill silence on the given buffer position;
2078  * called from snd_pcm_playback_silence()
2079  */
2080 static int fill_silence_frames(struct snd_pcm_substream *substream,
2081                                snd_pcm_uframes_t off, snd_pcm_uframes_t frames)
2082 {
2083         if (substream->runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
2084             substream->runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED)
2085                 return interleaved_copy(substream, off, NULL, 0, frames,
2086                                         fill_silence);
2087         else
2088                 return noninterleaved_copy(substream, off, NULL, 0, frames,
2089                                            fill_silence);
2090 }
2091
2092 /* sanity-check for read/write methods */
2093 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2094 {
2095         struct snd_pcm_runtime *runtime;
2096         if (PCM_RUNTIME_CHECK(substream))
2097                 return -ENXIO;
2098         runtime = substream->runtime;
2099         if (snd_BUG_ON(!substream->ops->copy_user && !runtime->dma_area))
2100                 return -EINVAL;
2101         if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2102                 return -EBADFD;
2103         return 0;
2104 }
2105
2106 static int pcm_accessible_state(struct snd_pcm_runtime *runtime)
2107 {
2108         switch (runtime->status->state) {
2109         case SNDRV_PCM_STATE_PREPARED:
2110         case SNDRV_PCM_STATE_RUNNING:
2111         case SNDRV_PCM_STATE_PAUSED:
2112                 return 0;
2113         case SNDRV_PCM_STATE_XRUN:
2114                 return -EPIPE;
2115         case SNDRV_PCM_STATE_SUSPENDED:
2116                 return -ESTRPIPE;
2117         default:
2118                 return -EBADFD;
2119         }
2120 }
2121
2122 /* update to the given appl_ptr and call ack callback if needed;
2123  * when an error is returned, take back to the original value
2124  */
2125 int pcm_lib_apply_appl_ptr(struct snd_pcm_substream *substream,
2126                            snd_pcm_uframes_t appl_ptr)
2127 {
2128         struct snd_pcm_runtime *runtime = substream->runtime;
2129         snd_pcm_uframes_t old_appl_ptr = runtime->control->appl_ptr;
2130         int ret;
2131
2132         if (old_appl_ptr == appl_ptr)
2133                 return 0;
2134
2135         runtime->control->appl_ptr = appl_ptr;
2136         if (substream->ops->ack) {
2137                 ret = substream->ops->ack(substream);
2138                 if (ret < 0) {
2139                         runtime->control->appl_ptr = old_appl_ptr;
2140                         return ret;
2141                 }
2142         }
2143
2144         trace_applptr(substream, old_appl_ptr, appl_ptr);
2145
2146         return 0;
2147 }
2148
2149 /* the common loop for read/write data */
2150 snd_pcm_sframes_t __snd_pcm_lib_xfer(struct snd_pcm_substream *substream,
2151                                      void *data, bool interleaved,
2152                                      snd_pcm_uframes_t size, bool in_kernel)
2153 {
2154         struct snd_pcm_runtime *runtime = substream->runtime;
2155         snd_pcm_uframes_t xfer = 0;
2156         snd_pcm_uframes_t offset = 0;
2157         snd_pcm_uframes_t avail;
2158         pcm_copy_f writer;
2159         pcm_transfer_f transfer;
2160         bool nonblock;
2161         bool is_playback;
2162         int err;
2163
2164         err = pcm_sanity_check(substream);
2165         if (err < 0)
2166                 return err;
2167
2168         is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
2169         if (interleaved) {
2170                 if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2171                     runtime->channels > 1)
2172                         return -EINVAL;
2173                 writer = interleaved_copy;
2174         } else {
2175                 if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2176                         return -EINVAL;
2177                 writer = noninterleaved_copy;
2178         }
2179
2180         if (!data) {
2181                 if (is_playback)
2182                         transfer = fill_silence;
2183                 else
2184                         return -EINVAL;
2185         } else if (in_kernel) {
2186                 if (substream->ops->copy_kernel)
2187                         transfer = substream->ops->copy_kernel;
2188                 else
2189                         transfer = is_playback ?
2190                                 default_write_copy_kernel : default_read_copy_kernel;
2191         } else {
2192                 if (substream->ops->copy_user)
2193                         transfer = (pcm_transfer_f)substream->ops->copy_user;
2194                 else
2195                         transfer = is_playback ?
2196                                 default_write_copy : default_read_copy;
2197         }
2198
2199         if (size == 0)
2200                 return 0;
2201
2202         nonblock = !!(substream->f_flags & O_NONBLOCK);
2203
2204         snd_pcm_stream_lock_irq(substream);
2205         err = pcm_accessible_state(runtime);
2206         if (err < 0)
2207                 goto _end_unlock;
2208
2209         runtime->twake = runtime->control->avail_min ? : 1;
2210         if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2211                 snd_pcm_update_hw_ptr(substream);
2212
2213         /*
2214          * If size < start_threshold, wait indefinitely. Another
2215          * thread may start capture
2216          */
2217         if (!is_playback &&
2218             runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2219             size >= runtime->start_threshold) {
2220                 err = snd_pcm_start(substream);
2221                 if (err < 0)
2222                         goto _end_unlock;
2223         }
2224
2225         avail = snd_pcm_avail(substream);
2226
2227         while (size > 0) {
2228                 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2229                 snd_pcm_uframes_t cont;
2230                 if (!avail) {
2231                         if (!is_playback &&
2232                             runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
2233                                 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2234                                 goto _end_unlock;
2235                         }
2236                         if (nonblock) {
2237                                 err = -EAGAIN;
2238                                 goto _end_unlock;
2239                         }
2240                         runtime->twake = min_t(snd_pcm_uframes_t, size,
2241                                         runtime->control->avail_min ? : 1);
2242                         err = wait_for_avail(substream, &avail);
2243                         if (err < 0)
2244                                 goto _end_unlock;
2245                         if (!avail)
2246                                 continue; /* draining */
2247                 }
2248                 frames = size > avail ? avail : size;
2249                 appl_ptr = READ_ONCE(runtime->control->appl_ptr);
2250                 appl_ofs = appl_ptr % runtime->buffer_size;
2251                 cont = runtime->buffer_size - appl_ofs;
2252                 if (frames > cont)
2253                         frames = cont;
2254                 if (snd_BUG_ON(!frames)) {
2255                         err = -EINVAL;
2256                         goto _end_unlock;
2257                 }
2258                 snd_pcm_stream_unlock_irq(substream);
2259                 err = writer(substream, appl_ofs, data, offset, frames,
2260                              transfer);
2261                 snd_pcm_stream_lock_irq(substream);
2262                 if (err < 0)
2263                         goto _end_unlock;
2264                 err = pcm_accessible_state(runtime);
2265                 if (err < 0)
2266                         goto _end_unlock;
2267                 appl_ptr += frames;
2268                 if (appl_ptr >= runtime->boundary)
2269                         appl_ptr -= runtime->boundary;
2270                 err = pcm_lib_apply_appl_ptr(substream, appl_ptr);
2271                 if (err < 0)
2272                         goto _end_unlock;
2273
2274                 offset += frames;
2275                 size -= frames;
2276                 xfer += frames;
2277                 avail -= frames;
2278                 if (is_playback &&
2279                     runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2280                     snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2281                         err = snd_pcm_start(substream);
2282                         if (err < 0)
2283                                 goto _end_unlock;
2284                 }
2285         }
2286  _end_unlock:
2287         runtime->twake = 0;
2288         if (xfer > 0 && err >= 0)
2289                 snd_pcm_update_state(substream, runtime);
2290         snd_pcm_stream_unlock_irq(substream);
2291         return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2292 }
2293 EXPORT_SYMBOL(__snd_pcm_lib_xfer);
2294
2295 /*
2296  * standard channel mapping helpers
2297  */
2298
2299 /* default channel maps for multi-channel playbacks, up to 8 channels */
2300 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2301         { .channels = 1,
2302           .map = { SNDRV_CHMAP_MONO } },
2303         { .channels = 2,
2304           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2305         { .channels = 4,
2306           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2307                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2308         { .channels = 6,
2309           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2310                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2311                    SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2312         { .channels = 8,
2313           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2314                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2315                    SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2316                    SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2317         { }
2318 };
2319 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2320
2321 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2322 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2323         { .channels = 1,
2324           .map = { SNDRV_CHMAP_MONO } },
2325         { .channels = 2,
2326           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2327         { .channels = 4,
2328           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2329                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2330         { .channels = 6,
2331           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2332                    SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2333                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2334         { .channels = 8,
2335           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2336                    SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2337                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2338                    SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2339         { }
2340 };
2341 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2342
2343 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2344 {
2345         if (ch > info->max_channels)
2346                 return false;
2347         return !info->channel_mask || (info->channel_mask & (1U << ch));
2348 }
2349
2350 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2351                               struct snd_ctl_elem_info *uinfo)
2352 {
2353         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2354
2355         uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2356         uinfo->count = info->max_channels;
2357         uinfo->value.integer.min = 0;
2358         uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2359         return 0;
2360 }
2361
2362 /* get callback for channel map ctl element
2363  * stores the channel position firstly matching with the current channels
2364  */
2365 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2366                              struct snd_ctl_elem_value *ucontrol)
2367 {
2368         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2369         unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2370         struct snd_pcm_substream *substream;
2371         const struct snd_pcm_chmap_elem *map;
2372
2373         if (!info->chmap)
2374                 return -EINVAL;
2375         substream = snd_pcm_chmap_substream(info, idx);
2376         if (!substream)
2377                 return -ENODEV;
2378         memset(ucontrol->value.integer.value, 0,
2379                sizeof(long) * info->max_channels);
2380         if (!substream->runtime)
2381                 return 0; /* no channels set */
2382         for (map = info->chmap; map->channels; map++) {
2383                 int i;
2384                 if (map->channels == substream->runtime->channels &&
2385                     valid_chmap_channels(info, map->channels)) {
2386                         for (i = 0; i < map->channels; i++)
2387                                 ucontrol->value.integer.value[i] = map->map[i];
2388                         return 0;
2389                 }
2390         }
2391         return -EINVAL;
2392 }
2393
2394 /* tlv callback for channel map ctl element
2395  * expands the pre-defined channel maps in a form of TLV
2396  */
2397 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2398                              unsigned int size, unsigned int __user *tlv)
2399 {
2400         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2401         const struct snd_pcm_chmap_elem *map;
2402         unsigned int __user *dst;
2403         int c, count = 0;
2404
2405         if (!info->chmap)
2406                 return -EINVAL;
2407         if (size < 8)
2408                 return -ENOMEM;
2409         if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2410                 return -EFAULT;
2411         size -= 8;
2412         dst = tlv + 2;
2413         for (map = info->chmap; map->channels; map++) {
2414                 int chs_bytes = map->channels * 4;
2415                 if (!valid_chmap_channels(info, map->channels))
2416                         continue;
2417                 if (size < 8)
2418                         return -ENOMEM;
2419                 if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2420                     put_user(chs_bytes, dst + 1))
2421                         return -EFAULT;
2422                 dst += 2;
2423                 size -= 8;
2424                 count += 8;
2425                 if (size < chs_bytes)
2426                         return -ENOMEM;
2427                 size -= chs_bytes;
2428                 count += chs_bytes;
2429                 for (c = 0; c < map->channels; c++) {
2430                         if (put_user(map->map[c], dst))
2431                                 return -EFAULT;
2432                         dst++;
2433                 }
2434         }
2435         if (put_user(count, tlv + 1))
2436                 return -EFAULT;
2437         return 0;
2438 }
2439
2440 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2441 {
2442         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2443         info->pcm->streams[info->stream].chmap_kctl = NULL;
2444         kfree(info);
2445 }
2446
2447 /**
2448  * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2449  * @pcm: the assigned PCM instance
2450  * @stream: stream direction
2451  * @chmap: channel map elements (for query)
2452  * @max_channels: the max number of channels for the stream
2453  * @private_value: the value passed to each kcontrol's private_value field
2454  * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2455  *
2456  * Create channel-mapping control elements assigned to the given PCM stream(s).
2457  * Return: Zero if successful, or a negative error value.
2458  */
2459 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2460                            const struct snd_pcm_chmap_elem *chmap,
2461                            int max_channels,
2462                            unsigned long private_value,
2463                            struct snd_pcm_chmap **info_ret)
2464 {
2465         struct snd_pcm_chmap *info;
2466         struct snd_kcontrol_new knew = {
2467                 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
2468                 .access = SNDRV_CTL_ELEM_ACCESS_READ |
2469                         SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2470                         SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2471                 .info = pcm_chmap_ctl_info,
2472                 .get = pcm_chmap_ctl_get,
2473                 .tlv.c = pcm_chmap_ctl_tlv,
2474         };
2475         int err;
2476
2477         if (WARN_ON(pcm->streams[stream].chmap_kctl))
2478                 return -EBUSY;
2479         info = kzalloc(sizeof(*info), GFP_KERNEL);
2480         if (!info)
2481                 return -ENOMEM;
2482         info->pcm = pcm;
2483         info->stream = stream;
2484         info->chmap = chmap;
2485         info->max_channels = max_channels;
2486         if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2487                 knew.name = "Playback Channel Map";
2488         else
2489                 knew.name = "Capture Channel Map";
2490         knew.device = pcm->device;
2491         knew.count = pcm->streams[stream].substream_count;
2492         knew.private_value = private_value;
2493         info->kctl = snd_ctl_new1(&knew, info);
2494         if (!info->kctl) {
2495                 kfree(info);
2496                 return -ENOMEM;
2497         }
2498         info->kctl->private_free = pcm_chmap_ctl_private_free;
2499         err = snd_ctl_add(pcm->card, info->kctl);
2500         if (err < 0)
2501                 return err;
2502         pcm->streams[stream].chmap_kctl = info->kctl;
2503         if (info_ret)
2504                 *info_ret = info;
2505         return 0;
2506 }
2507 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);