sound/core/pcm_lib.c

   1 /*
   2  *  Digital Audio (PCM) abstract layer
   3  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   4  *                   Abramo Bagnara <abramo@alsa-project.org>
   5  *
   6  *
   7  *   This program is free software; you can redistribute it and/or modify
   8  *   it under the terms of the GNU General Public License as published by
   9  *   the Free Software Foundation; either version 2 of the License, or
  10  *   (at your option) any later version.
  11  *
  12  *   This program is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with this program; if not, write to the Free Software
  19  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  20  *
  21  */
  22
  23 #include <linux/slab.h>
  24 #include <linux/sched/signal.h>
  25 #include <linux/time.h>
  26 #include <linux/math64.h>
  27 #include <linux/export.h>
  28 #include <sound/core.h>
  29 #include <sound/control.h>
  30 #include <sound/tlv.h>
  31 #include <sound/info.h>
  32 #include <sound/pcm.h>
  33 #include <sound/pcm_params.h>
  34 #include <sound/timer.h>
  35
  36 #include "pcm_local.h"
  37
  38 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
  39 #define CREATE_TRACE_POINTS
  40 #include "pcm_trace.h"
  41 #else
  42 #define trace_hwptr(substream, pos, in_interrupt)
  43 #define trace_xrun(substream)
  44 #define trace_hw_ptr_error(substream, reason)
  45 #endif
  46
  47 /*
  48  * fill ring buffer with silence
  49  * runtime->silence_start: starting pointer to silence area
  50  * runtime->silence_filled: size filled with silence
  51  * runtime->silence_threshold: threshold from application
  52  * runtime->silence_size: maximal size from application
  53  *
  54  * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
  55  */
  56 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
  57 {
  58         struct snd_pcm_runtime *runtime = substream->runtime;
  59         snd_pcm_uframes_t frames, ofs, transfer;
  60
  61         if (runtime->silence_size < runtime->boundary) {
  62                 snd_pcm_sframes_t noise_dist, n;
  63                 if (runtime->silence_start != runtime->control->appl_ptr) {
  64                         n = runtime->control->appl_ptr - runtime->silence_start;
  65                         if (n < 0)
  66                                 n += runtime->boundary;
  67                         if ((snd_pcm_uframes_t)n < runtime->silence_filled)
  68                                 runtime->silence_filled -= n;
  69                         else
  70                                 runtime->silence_filled = 0;
  71                         runtime->silence_start = runtime->control->appl_ptr;
  72                 }
  73                 if (runtime->silence_filled >= runtime->buffer_size)
  74                         return;
  75                 noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
  76                 if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
  77                         return;
  78                 frames = runtime->silence_threshold - noise_dist;
  79                 if (frames > runtime->silence_size)
  80                         frames = runtime->silence_size;
  81         } else {
  82                 if (new_hw_ptr == ULONG_MAX) {  /* initialization */
  83                         snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
  84                         if (avail > runtime->buffer_size)
  85                                 avail = runtime->buffer_size;
  86                         runtime->silence_filled = avail > 0 ? avail : 0;
  87                         runtime->silence_start = (runtime->status->hw_ptr +
  88                                                   runtime->silence_filled) %
  89                                                  runtime->boundary;
  90                 } else {
  91                         ofs = runtime->status->hw_ptr;
  92                         frames = new_hw_ptr - ofs;
  93                         if ((snd_pcm_sframes_t)frames < 0)
  94                                 frames += runtime->boundary;
  95                         runtime->silence_filled -= frames;
  96                         if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
  97                                 runtime->silence_filled = 0;
  98                                 runtime->silence_start = new_hw_ptr;
  99                         } else {
 100                                 runtime->silence_start = ofs;
 101                         }
 102                 }
 103                 frames = runtime->buffer_size - runtime->silence_filled;
 104         }
 105         if (snd_BUG_ON(frames > runtime->buffer_size))
 106                 return;
 107         if (frames == 0)
 108                 return;
 109         ofs = runtime->silence_start % runtime->buffer_size;
 110         while (frames > 0) {
 111                 transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
 112                 if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
 113                     runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
 114                         if (substream->ops->silence) {
 115                                 int err;
 116                                 err = substream->ops->silence(substream, -1, ofs, transfer);
 117                                 snd_BUG_ON(err < 0);
 118                         } else {
 119                                 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
 120                                 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
 121                         }
 122                 } else {
 123                         unsigned int c;
 124                         unsigned int channels = runtime->channels;
 125                         if (substream->ops->silence) {
 126                                 for (c = 0; c < channels; ++c) {
 127                                         int err;
 128                                         err = substream->ops->silence(substream, c, ofs, transfer);
 129                                         snd_BUG_ON(err < 0);
 130                                 }
 131                         } else {
 132                                 size_t dma_csize = runtime->dma_bytes / channels;
 133                                 for (c = 0; c < channels; ++c) {
 134                                         char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
 135                                         snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
 136                                 }
 137                         }
 138                 }
 139                 runtime->silence_filled += transfer;
 140                 frames -= transfer;
 141                 ofs = 0;
 142         }
 143 }
 144
 145 #ifdef CONFIG_SND_DEBUG
 146 void snd_pcm_debug_name(struct snd_pcm_substream *substream,
 147                            char *name, size_t len)
 148 {
 149         snprintf(name, len, "pcmC%dD%d%c:%d",
 150                  substream->pcm->card->number,
 151                  substream->pcm->device,
 152                  substream->stream ? 'c' : 'p',
 153                  substream->number);
 154 }
 155 EXPORT_SYMBOL(snd_pcm_debug_name);
 156 #endif
 157
 158 #define XRUN_DEBUG_BASIC        (1<<0)
 159 #define XRUN_DEBUG_STACK        (1<<1)  /* dump also stack */
 160 #define XRUN_DEBUG_JIFFIESCHECK (1<<2)  /* do jiffies check */
 161
 162 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 163
 164 #define xrun_debug(substream, mask) \
 165                         ((substream)->pstr->xrun_debug & (mask))
 166 #else
 167 #define xrun_debug(substream, mask)     0
 168 #endif
 169
 170 #define dump_stack_on_xrun(substream) do {                      \
 171                 if (xrun_debug(substream, XRUN_DEBUG_STACK))    \
 172                         dump_stack();                           \
 173         } while (0)
 174
 175 static void xrun(struct snd_pcm_substream *substream)
 176 {
 177         struct snd_pcm_runtime *runtime = substream->runtime;
 178
 179         trace_xrun(substream);
 180         if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
 181                 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 182         snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 183         if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
 184                 char name[16];
 185                 snd_pcm_debug_name(substream, name, sizeof(name));
 186                 pcm_warn(substream->pcm, "XRUN: %s\n", name);
 187                 dump_stack_on_xrun(substream);
 188         }
 189 }
 190
 191 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 192 #define hw_ptr_error(substream, in_interrupt, reason, fmt, args...)     \
 193         do {                                                            \
 194                 trace_hw_ptr_error(substream, reason);  \
 195                 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {          \
 196                         pr_err_ratelimited("ALSA: PCM: [%c] " reason ": " fmt, \
 197                                            (in_interrupt) ? 'Q' : 'P', ##args); \
 198                         dump_stack_on_xrun(substream);                  \
 199                 }                                                       \
 200         } while (0)
 201
 202 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
 203
 204 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
 205
 206 #endif
 207
 208 int snd_pcm_update_state(struct snd_pcm_substream *substream,
 209                          struct snd_pcm_runtime *runtime)
 210 {
 211         snd_pcm_uframes_t avail;
 212
 213         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 214                 avail = snd_pcm_playback_avail(runtime);
 215         else
 216                 avail = snd_pcm_capture_avail(runtime);
 217         if (avail > runtime->avail_max)
 218                 runtime->avail_max = avail;
 219         if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
 220                 if (avail >= runtime->buffer_size) {
 221                         snd_pcm_drain_done(substream);
 222                         return -EPIPE;
 223                 }
 224         } else {
 225                 if (avail >= runtime->stop_threshold) {
 226                         xrun(substream);
 227                         return -EPIPE;
 228                 }
 229         }
 230         if (runtime->twake) {
 231                 if (avail >= runtime->twake)
 232                         wake_up(&runtime->tsleep);
 233         } else if (avail >= runtime->control->avail_min)
 234                 wake_up(&runtime->sleep);
 235         return 0;
 236 }
 237
 238 static void update_audio_tstamp(struct snd_pcm_substream *substream,
 239                                 struct timespec *curr_tstamp,
 240                                 struct timespec *audio_tstamp)
 241 {
 242         struct snd_pcm_runtime *runtime = substream->runtime;
 243         u64 audio_frames, audio_nsecs;
 244         struct timespec driver_tstamp;
 245
 246         if (runtime->tstamp_mode != SNDRV_PCM_TSTAMP_ENABLE)
 247                 return;
 248
 249         if (!(substream->ops->get_time_info) ||
 250                 (runtime->audio_tstamp_report.actual_type ==
 251                         SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
 252
 253                 /*
 254                  * provide audio timestamp derived from pointer position
 255                  * add delay only if requested
 256                  */
 257
 258                 audio_frames = runtime->hw_ptr_wrap + runtime->status->hw_ptr;
 259
 260                 if (runtime->audio_tstamp_config.report_delay) {
 261                         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 262                                 audio_frames -=  runtime->delay;
 263                         else
 264                                 audio_frames +=  runtime->delay;
 265                 }
 266                 audio_nsecs = div_u64(audio_frames * 1000000000LL,
 267                                 runtime->rate);
 268                 *audio_tstamp = ns_to_timespec(audio_nsecs);
 269         }
 270         runtime->status->audio_tstamp = *audio_tstamp;
 271         runtime->status->tstamp = *curr_tstamp;
 272
 273         /*
 274          * re-take a driver timestamp to let apps detect if the reference tstamp
 275          * read by low-level hardware was provided with a delay
 276          */
 277         snd_pcm_gettime(substream->runtime, (struct timespec *)&driver_tstamp);
 278         runtime->driver_tstamp = driver_tstamp;
 279 }
 280
 281 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
 282                                   unsigned int in_interrupt)
 283 {
 284         struct snd_pcm_runtime *runtime = substream->runtime;
 285         snd_pcm_uframes_t pos;
 286         snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
 287         snd_pcm_sframes_t hdelta, delta;
 288         unsigned long jdelta;
 289         unsigned long curr_jiffies;
 290         struct timespec curr_tstamp;
 291         struct timespec audio_tstamp;
 292         int crossed_boundary = 0;
 293
 294         old_hw_ptr = runtime->status->hw_ptr;
 295
 296         /*
 297          * group pointer, time and jiffies reads to allow for more
 298          * accurate correlations/corrections.
 299          * The values are stored at the end of this routine after
 300          * corrections for hw_ptr position
 301          */
 302         pos = substream->ops->pointer(substream);
 303         curr_jiffies = jiffies;
 304         if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) {
 305                 if ((substream->ops->get_time_info) &&
 306                         (runtime->audio_tstamp_config.type_requested != SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)) {
 307                         substream->ops->get_time_info(substream, &curr_tstamp,
 308                                                 &audio_tstamp,
 309                                                 &runtime->audio_tstamp_config,
 310                                                 &runtime->audio_tstamp_report);
 311
 312                         /* re-test in case tstamp type is not supported in hardware and was demoted to DEFAULT */
 313                         if (runtime->audio_tstamp_report.actual_type == SNDRV_PCM_AUDIO_TSTAMP_TYPE_DEFAULT)
 314                                 snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
 315                 } else
 316                         snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
 317         }
 318
 319         if (pos == SNDRV_PCM_POS_XRUN) {
 320                 xrun(substream);
 321                 return -EPIPE;
 322         }
 323         if (pos >= runtime->buffer_size) {
 324                 if (printk_ratelimit()) {
 325                         char name[16];
 326                         snd_pcm_debug_name(substream, name, sizeof(name));
 327                         pcm_err(substream->pcm,
 328                                 "invalid position: %s, pos = %ld, buffer size = %ld, period size = %ld\n",
 329                                 name, pos, runtime->buffer_size,
 330                                 runtime->period_size);
 331                 }
 332                 pos = 0;
 333         }
 334         pos -= pos % runtime->min_align;
 335         trace_hwptr(substream, pos, in_interrupt);
 336         hw_base = runtime->hw_ptr_base;
 337         new_hw_ptr = hw_base + pos;
 338         if (in_interrupt) {
 339                 /* we know that one period was processed */
 340                 /* delta = "expected next hw_ptr" for in_interrupt != 0 */
 341                 delta = runtime->hw_ptr_interrupt + runtime->period_size;
 342                 if (delta > new_hw_ptr) {
 343                         /* check for double acknowledged interrupts */
 344                         hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 345                         if (hdelta > runtime->hw_ptr_buffer_jiffies/2 + 1) {
 346                                 hw_base += runtime->buffer_size;
 347                                 if (hw_base >= runtime->boundary) {
 348                                         hw_base = 0;
 349                                         crossed_boundary++;
 350                                 }
 351                                 new_hw_ptr = hw_base + pos;
 352                                 goto __delta;
 353                         }
 354                 }
 355         }
 356         /* new_hw_ptr might be lower than old_hw_ptr in case when */
 357         /* pointer crosses the end of the ring buffer */
 358         if (new_hw_ptr < old_hw_ptr) {
 359                 hw_base += runtime->buffer_size;
 360                 if (hw_base >= runtime->boundary) {
 361                         hw_base = 0;
 362                         crossed_boundary++;
 363                 }
 364                 new_hw_ptr = hw_base + pos;
 365         }
 366       __delta:
 367         delta = new_hw_ptr - old_hw_ptr;
 368         if (delta < 0)
 369                 delta += runtime->boundary;
 370
 371         if (runtime->no_period_wakeup) {
 372                 snd_pcm_sframes_t xrun_threshold;
 373                 /*
 374                  * Without regular period interrupts, we have to check
 375                  * the elapsed time to detect xruns.
 376                  */
 377                 jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 378                 if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
 379                         goto no_delta_check;
 380                 hdelta = jdelta - delta * HZ / runtime->rate;
 381                 xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
 382                 while (hdelta > xrun_threshold) {
 383                         delta += runtime->buffer_size;
 384                         hw_base += runtime->buffer_size;
 385                         if (hw_base >= runtime->boundary) {
 386                                 hw_base = 0;
 387                                 crossed_boundary++;
 388                         }
 389                         new_hw_ptr = hw_base + pos;
 390                         hdelta -= runtime->hw_ptr_buffer_jiffies;
 391                 }
 392                 goto no_delta_check;
 393         }
 394
 395         /* something must be really wrong */
 396         if (delta >= runtime->buffer_size + runtime->period_size) {
 397                 hw_ptr_error(substream, in_interrupt, "Unexpected hw_ptr",
 398                              "(stream=%i, pos=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
 399                              substream->stream, (long)pos,
 400                              (long)new_hw_ptr, (long)old_hw_ptr);
 401                 return 0;
 402         }
 403
 404         /* Do jiffies check only in xrun_debug mode */
 405         if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
 406                 goto no_jiffies_check;
 407
 408         /* Skip the jiffies check for hardwares with BATCH flag.
 409          * Such hardware usually just increases the position at each IRQ,
 410          * thus it can't give any strange position.
 411          */
 412         if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
 413                 goto no_jiffies_check;
 414         hdelta = delta;
 415         if (hdelta < runtime->delay)
 416                 goto no_jiffies_check;
 417         hdelta -= runtime->delay;
 418         jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 419         if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
 420                 delta = jdelta /
 421                         (((runtime->period_size * HZ) / runtime->rate)
 422                                                                 + HZ/100);
 423                 /* move new_hw_ptr according jiffies not pos variable */
 424                 new_hw_ptr = old_hw_ptr;
 425                 hw_base = delta;
 426                 /* use loop to avoid checks for delta overflows */
 427                 /* the delta value is small or zero in most cases */
 428                 while (delta > 0) {
 429                         new_hw_ptr += runtime->period_size;
 430                         if (new_hw_ptr >= runtime->boundary) {
 431                                 new_hw_ptr -= runtime->boundary;
 432                                 crossed_boundary--;
 433                         }
 434                         delta--;
 435                 }
 436                 /* align hw_base to buffer_size */
 437                 hw_ptr_error(substream, in_interrupt, "hw_ptr skipping",
 438                              "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
 439                              (long)pos, (long)hdelta,
 440                              (long)runtime->period_size, jdelta,
 441                              ((hdelta * HZ) / runtime->rate), hw_base,
 442                              (unsigned long)old_hw_ptr,
 443                              (unsigned long)new_hw_ptr);
 444                 /* reset values to proper state */
 445                 delta = 0;
 446                 hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
 447         }
 448  no_jiffies_check:
 449         if (delta > runtime->period_size + runtime->period_size / 2) {
 450                 hw_ptr_error(substream, in_interrupt,
 451                              "Lost interrupts?",
 452                              "(stream=%i, delta=%ld, new_hw_ptr=%ld, old_hw_ptr=%ld)\n",
 453                              substream->stream, (long)delta,
 454                              (long)new_hw_ptr,
 455                              (long)old_hw_ptr);
 456         }
 457
 458  no_delta_check:
 459         if (runtime->status->hw_ptr == new_hw_ptr) {
 460                 update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
 461                 return 0;
 462         }
 463
 464         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 465             runtime->silence_size > 0)
 466                 snd_pcm_playback_silence(substream, new_hw_ptr);
 467
 468         if (in_interrupt) {
 469                 delta = new_hw_ptr - runtime->hw_ptr_interrupt;
 470                 if (delta < 0)
 471                         delta += runtime->boundary;
 472                 delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
 473                 runtime->hw_ptr_interrupt += delta;
 474                 if (runtime->hw_ptr_interrupt >= runtime->boundary)
 475                         runtime->hw_ptr_interrupt -= runtime->boundary;
 476         }
 477         runtime->hw_ptr_base = hw_base;
 478         runtime->status->hw_ptr = new_hw_ptr;
 479         runtime->hw_ptr_jiffies = curr_jiffies;
 480         if (crossed_boundary) {
 481                 snd_BUG_ON(crossed_boundary != 1);
 482                 runtime->hw_ptr_wrap += runtime->boundary;
 483         }
 484
 485         update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp);
 486
 487         return snd_pcm_update_state(substream, runtime);
 488 }
 489
 490 /* CAUTION: call it with irq disabled */
 491 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
 492 {
 493         return snd_pcm_update_hw_ptr0(substream, 0);
 494 }
 495
 496 /**
 497  * snd_pcm_set_ops - set the PCM operators
 498  * @pcm: the pcm instance
 499  * @direction: stream direction, SNDRV_PCM_STREAM_XXX
 500  * @ops: the operator table
 501  *
 502  * Sets the given PCM operators to the pcm instance.
 503  */
 504 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction,
 505                      const struct snd_pcm_ops *ops)
 506 {
 507         struct snd_pcm_str *stream = &pcm->streams[direction];
 508         struct snd_pcm_substream *substream;
 509
 510         for (substream = stream->substream; substream != NULL; substream = substream->next)
 511                 substream->ops = ops;
 512 }
 513
 514 EXPORT_SYMBOL(snd_pcm_set_ops);
 515
 516 /**
 517  * snd_pcm_sync - set the PCM sync id
 518  * @substream: the pcm substream
 519  *
 520  * Sets the PCM sync identifier for the card.
 521  */
 522 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
 523 {
 524         struct snd_pcm_runtime *runtime = substream->runtime;
 525
 526         runtime->sync.id32[0] = substream->pcm->card->number;
 527         runtime->sync.id32[1] = -1;
 528         runtime->sync.id32[2] = -1;
 529         runtime->sync.id32[3] = -1;
 530 }
 531
 532 EXPORT_SYMBOL(snd_pcm_set_sync);
 533
 534 /*
 535  *  Standard ioctl routine
 536  */
 537
 538 static inline unsigned int div32(unsigned int a, unsigned int b,
 539                                  unsigned int *r)
 540 {
 541         if (b == 0) {
 542                 *r = 0;
 543                 return UINT_MAX;
 544         }
 545         *r = a % b;
 546         return a / b;
 547 }
 548
 549 static inline unsigned int div_down(unsigned int a, unsigned int b)
 550 {
 551         if (b == 0)
 552                 return UINT_MAX;
 553         return a / b;
 554 }
 555
 556 static inline unsigned int div_up(unsigned int a, unsigned int b)
 557 {
 558         unsigned int r;
 559         unsigned int q;
 560         if (b == 0)
 561                 return UINT_MAX;
 562         q = div32(a, b, &r);
 563         if (r)
 564                 ++q;
 565         return q;
 566 }
 567
 568 static inline unsigned int mul(unsigned int a, unsigned int b)
 569 {
 570         if (a == 0)
 571                 return 0;
 572         if (div_down(UINT_MAX, a) < b)
 573                 return UINT_MAX;
 574         return a * b;
 575 }
 576
 577 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
 578                                     unsigned int c, unsigned int *r)
 579 {
 580         u_int64_t n = (u_int64_t) a * b;
 581         if (c == 0) {
 582                 snd_BUG_ON(!n);
 583                 *r = 0;
 584                 return UINT_MAX;
 585         }
 586         n = div_u64_rem(n, c, r);
 587         if (n >= UINT_MAX) {
 588                 *r = 0;
 589                 return UINT_MAX;
 590         }
 591         return n;
 592 }
 593
 594 /**
 595  * snd_interval_refine - refine the interval value of configurator
 596  * @i: the interval value to refine
 597  * @v: the interval value to refer to
 598  *
 599  * Refines the interval value with the reference value.
 600  * The interval is changed to the range satisfying both intervals.
 601  * The interval status (min, max, integer, etc.) are evaluated.
 602  *
 603  * Return: Positive if the value is changed, zero if it's not changed, or a
 604  * negative error code.
 605  */
 606 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
 607 {
 608         int changed = 0;
 609         if (snd_BUG_ON(snd_interval_empty(i)))
 610                 return -EINVAL;
 611         if (i->min < v->min) {
 612                 i->min = v->min;
 613                 i->openmin = v->openmin;
 614                 changed = 1;
 615         } else if (i->min == v->min && !i->openmin && v->openmin) {
 616                 i->openmin = 1;
 617                 changed = 1;
 618         }
 619         if (i->max > v->max) {
 620                 i->max = v->max;
 621                 i->openmax = v->openmax;
 622                 changed = 1;
 623         } else if (i->max == v->max && !i->openmax && v->openmax) {
 624                 i->openmax = 1;
 625                 changed = 1;
 626         }
 627         if (!i->integer && v->integer) {
 628                 i->integer = 1;
 629                 changed = 1;
 630         }
 631         if (i->integer) {
 632                 if (i->openmin) {
 633                         i->min++;
 634                         i->openmin = 0;
 635                 }
 636                 if (i->openmax) {
 637                         i->max--;
 638                         i->openmax = 0;
 639                 }
 640         } else if (!i->openmin && !i->openmax && i->min == i->max)
 641                 i->integer = 1;
 642         if (snd_interval_checkempty(i)) {
 643                 snd_interval_none(i);
 644                 return -EINVAL;
 645         }
 646         return changed;
 647 }
 648
 649 EXPORT_SYMBOL(snd_interval_refine);
 650
 651 static int snd_interval_refine_first(struct snd_interval *i)
 652 {
 653         if (snd_BUG_ON(snd_interval_empty(i)))
 654                 return -EINVAL;
 655         if (snd_interval_single(i))
 656                 return 0;
 657         i->max = i->min;
 658         i->openmax = i->openmin;
 659         if (i->openmax)
 660                 i->max++;
 661         return 1;
 662 }
 663
 664 static int snd_interval_refine_last(struct snd_interval *i)
 665 {
 666         if (snd_BUG_ON(snd_interval_empty(i)))
 667                 return -EINVAL;
 668         if (snd_interval_single(i))
 669                 return 0;
 670         i->min = i->max;
 671         i->openmin = i->openmax;
 672         if (i->openmin)
 673                 i->min--;
 674         return 1;
 675 }
 676
 677 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 678 {
 679         if (a->empty || b->empty) {
 680                 snd_interval_none(c);
 681                 return;
 682         }
 683         c->empty = 0;
 684         c->min = mul(a->min, b->min);
 685         c->openmin = (a->openmin || b->openmin);
 686         c->max = mul(a->max,  b->max);
 687         c->openmax = (a->openmax || b->openmax);
 688         c->integer = (a->integer && b->integer);
 689 }
 690
 691 /**
 692  * snd_interval_div - refine the interval value with division
 693  * @a: dividend
 694  * @b: divisor
 695  * @c: quotient
 696  *
 697  * c = a / b
 698  *
 699  * Returns non-zero if the value is changed, zero if not changed.
 700  */
 701 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 702 {
 703         unsigned int r;
 704         if (a->empty || b->empty) {
 705                 snd_interval_none(c);
 706                 return;
 707         }
 708         c->empty = 0;
 709         c->min = div32(a->min, b->max, &r);
 710         c->openmin = (r || a->openmin || b->openmax);
 711         if (b->min > 0) {
 712                 c->max = div32(a->max, b->min, &r);
 713                 if (r) {
 714                         c->max++;
 715                         c->openmax = 1;
 716                 } else
 717                         c->openmax = (a->openmax || b->openmin);
 718         } else {
 719                 c->max = UINT_MAX;
 720                 c->openmax = 0;
 721         }
 722         c->integer = 0;
 723 }
 724
 725 /**
 726  * snd_interval_muldivk - refine the interval value
 727  * @a: dividend 1
 728  * @b: dividend 2
 729  * @k: divisor (as integer)
 730  * @c: result
 731   *
 732  * c = a * b / k
 733  *
 734  * Returns non-zero if the value is changed, zero if not changed.
 735  */
 736 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
 737                       unsigned int k, struct snd_interval *c)
 738 {
 739         unsigned int r;
 740         if (a->empty || b->empty) {
 741                 snd_interval_none(c);
 742                 return;
 743         }
 744         c->empty = 0;
 745         c->min = muldiv32(a->min, b->min, k, &r);
 746         c->openmin = (r || a->openmin || b->openmin);
 747         c->max = muldiv32(a->max, b->max, k, &r);
 748         if (r) {
 749                 c->max++;
 750                 c->openmax = 1;
 751         } else
 752                 c->openmax = (a->openmax || b->openmax);
 753         c->integer = 0;
 754 }
 755
 756 /**
 757  * snd_interval_mulkdiv - refine the interval value
 758  * @a: dividend 1
 759  * @k: dividend 2 (as integer)
 760  * @b: divisor
 761  * @c: result
 762  *
 763  * c = a * k / b
 764  *
 765  * Returns non-zero if the value is changed, zero if not changed.
 766  */
 767 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
 768                       const struct snd_interval *b, struct snd_interval *c)
 769 {
 770         unsigned int r;
 771         if (a->empty || b->empty) {
 772                 snd_interval_none(c);
 773                 return;
 774         }
 775         c->empty = 0;
 776         c->min = muldiv32(a->min, k, b->max, &r);
 777         c->openmin = (r || a->openmin || b->openmax);
 778         if (b->min > 0) {
 779                 c->max = muldiv32(a->max, k, b->min, &r);
 780                 if (r) {
 781                         c->max++;
 782                         c->openmax = 1;
 783                 } else
 784                         c->openmax = (a->openmax || b->openmin);
 785         } else {
 786                 c->max = UINT_MAX;
 787                 c->openmax = 0;
 788         }
 789         c->integer = 0;
 790 }
 791
 792 /* ---- */
 793
 794
 795 /**
 796  * snd_interval_ratnum - refine the interval value
 797  * @i: interval to refine
 798  * @rats_count: number of ratnum_t
 799  * @rats: ratnum_t array
 800  * @nump: pointer to store the resultant numerator
 801  * @denp: pointer to store the resultant denominator
 802  *
 803  * Return: Positive if the value is changed, zero if it's not changed, or a
 804  * negative error code.
 805  */
 806 int snd_interval_ratnum(struct snd_interval *i,
 807                         unsigned int rats_count, const struct snd_ratnum *rats,
 808                         unsigned int *nump, unsigned int *denp)
 809 {
 810         unsigned int best_num, best_den;
 811         int best_diff;
 812         unsigned int k;
 813         struct snd_interval t;
 814         int err;
 815         unsigned int result_num, result_den;
 816         int result_diff;
 817
 818         best_num = best_den = best_diff = 0;
 819         for (k = 0; k < rats_count; ++k) {
 820                 unsigned int num = rats[k].num;
 821                 unsigned int den;
 822                 unsigned int q = i->min;
 823                 int diff;
 824                 if (q == 0)
 825                         q = 1;
 826                 den = div_up(num, q);
 827                 if (den < rats[k].den_min)
 828                         continue;
 829                 if (den > rats[k].den_max)
 830                         den = rats[k].den_max;
 831                 else {
 832                         unsigned int r;
 833                         r = (den - rats[k].den_min) % rats[k].den_step;
 834                         if (r != 0)
 835                                 den -= r;
 836                 }
 837                 diff = num - q * den;
 838                 if (diff < 0)
 839                         diff = -diff;
 840                 if (best_num == 0 ||
 841                     diff * best_den < best_diff * den) {
 842                         best_diff = diff;
 843                         best_den = den;
 844                         best_num = num;
 845                 }
 846         }
 847         if (best_den == 0) {
 848                 i->empty = 1;
 849                 return -EINVAL;
 850         }
 851         t.min = div_down(best_num, best_den);
 852         t.openmin = !!(best_num % best_den);
 853
 854         result_num = best_num;
 855         result_diff = best_diff;
 856         result_den = best_den;
 857         best_num = best_den = best_diff = 0;
 858         for (k = 0; k < rats_count; ++k) {
 859                 unsigned int num = rats[k].num;
 860                 unsigned int den;
 861                 unsigned int q = i->max;
 862                 int diff;
 863                 if (q == 0) {
 864                         i->empty = 1;
 865                         return -EINVAL;
 866                 }
 867                 den = div_down(num, q);
 868                 if (den > rats[k].den_max)
 869                         continue;
 870                 if (den < rats[k].den_min)
 871                         den = rats[k].den_min;
 872                 else {
 873                         unsigned int r;
 874                         r = (den - rats[k].den_min) % rats[k].den_step;
 875                         if (r != 0)
 876                                 den += rats[k].den_step - r;
 877                 }
 878                 diff = q * den - num;
 879                 if (diff < 0)
 880                         diff = -diff;
 881                 if (best_num == 0 ||
 882                     diff * best_den < best_diff * den) {
 883                         best_diff = diff;
 884                         best_den = den;
 885                         best_num = num;
 886                 }
 887         }
 888         if (best_den == 0) {
 889                 i->empty = 1;
 890                 return -EINVAL;
 891         }
 892         t.max = div_up(best_num, best_den);
 893         t.openmax = !!(best_num % best_den);
 894         t.integer = 0;
 895         err = snd_interval_refine(i, &t);
 896         if (err < 0)
 897                 return err;
 898
 899         if (snd_interval_single(i)) {
 900                 if (best_diff * result_den < result_diff * best_den) {
 901                         result_num = best_num;
 902                         result_den = best_den;
 903                 }
 904                 if (nump)
 905                         *nump = result_num;
 906                 if (denp)
 907                         *denp = result_den;
 908         }
 909         return err;
 910 }
 911
 912 EXPORT_SYMBOL(snd_interval_ratnum);
 913
 914 /**
 915  * snd_interval_ratden - refine the interval value
 916  * @i: interval to refine
 917  * @rats_count: number of struct ratden
 918  * @rats: struct ratden array
 919  * @nump: pointer to store the resultant numerator
 920  * @denp: pointer to store the resultant denominator
 921  *
 922  * Return: Positive if the value is changed, zero if it's not changed, or a
 923  * negative error code.
 924  */
 925 static int snd_interval_ratden(struct snd_interval *i,
 926                                unsigned int rats_count,
 927                                const struct snd_ratden *rats,
 928                                unsigned int *nump, unsigned int *denp)
 929 {
 930         unsigned int best_num, best_diff, best_den;
 931         unsigned int k;
 932         struct snd_interval t;
 933         int err;
 934
 935         best_num = best_den = best_diff = 0;
 936         for (k = 0; k < rats_count; ++k) {
 937                 unsigned int num;
 938                 unsigned int den = rats[k].den;
 939                 unsigned int q = i->min;
 940                 int diff;
 941                 num = mul(q, den);
 942                 if (num > rats[k].num_max)
 943                         continue;
 944                 if (num < rats[k].num_min)
 945                         num = rats[k].num_max;
 946                 else {
 947                         unsigned int r;
 948                         r = (num - rats[k].num_min) % rats[k].num_step;
 949                         if (r != 0)
 950                                 num += rats[k].num_step - r;
 951                 }
 952                 diff = num - q * den;
 953                 if (best_num == 0 ||
 954                     diff * best_den < best_diff * den) {
 955                         best_diff = diff;
 956                         best_den = den;
 957                         best_num = num;
 958                 }
 959         }
 960         if (best_den == 0) {
 961                 i->empty = 1;
 962                 return -EINVAL;
 963         }
 964         t.min = div_down(best_num, best_den);
 965         t.openmin = !!(best_num % best_den);
 966
 967         best_num = best_den = best_diff = 0;
 968         for (k = 0; k < rats_count; ++k) {
 969                 unsigned int num;
 970                 unsigned int den = rats[k].den;
 971                 unsigned int q = i->max;
 972                 int diff;
 973                 num = mul(q, den);
 974                 if (num < rats[k].num_min)
 975                         continue;
 976                 if (num > rats[k].num_max)
 977                         num = rats[k].num_max;
 978                 else {
 979                         unsigned int r;
 980                         r = (num - rats[k].num_min) % rats[k].num_step;
 981                         if (r != 0)
 982                                 num -= r;
 983                 }
 984                 diff = q * den - num;
 985                 if (best_num == 0 ||
 986                     diff * best_den < best_diff * den) {
 987                         best_diff = diff;
 988                         best_den = den;
 989                         best_num = num;
 990                 }
 991         }
 992         if (best_den == 0) {
 993                 i->empty = 1;
 994                 return -EINVAL;
 995         }
 996         t.max = div_up(best_num, best_den);
 997         t.openmax = !!(best_num % best_den);
 998         t.integer = 0;
 999         err = snd_interval_refine(i, &t);
1000         if (err < 0)
1001                 return err;
1002
1003         if (snd_interval_single(i)) {
1004                 if (nump)
1005                         *nump = best_num;
1006                 if (denp)
1007                         *denp = best_den;
1008         }
1009         return err;
1010 }
1011
1012 /**
1013  * snd_interval_list - refine the interval value from the list
1014  * @i: the interval value to refine
1015  * @count: the number of elements in the list
1016  * @list: the value list
1017  * @mask: the bit-mask to evaluate
1018  *
1019  * Refines the interval value from the list.
1020  * When mask is non-zero, only the elements corresponding to bit 1 are
1021  * evaluated.
1022  *
1023  * Return: Positive if the value is changed, zero if it's not changed, or a
1024  * negative error code.
1025  */
1026 int snd_interval_list(struct snd_interval *i, unsigned int count,
1027                       const unsigned int *list, unsigned int mask)
1028 {
1029         unsigned int k;
1030         struct snd_interval list_range;
1031
1032         if (!count) {
1033                 i->empty = 1;
1034                 return -EINVAL;
1035         }
1036         snd_interval_any(&list_range);
1037         list_range.min = UINT_MAX;
1038         list_range.max = 0;
1039         for (k = 0; k < count; k++) {
1040                 if (mask && !(mask & (1 << k)))
1041                         continue;
1042                 if (!snd_interval_test(i, list[k]))
1043                         continue;
1044                 list_range.min = min(list_range.min, list[k]);
1045                 list_range.max = max(list_range.max, list[k]);
1046         }
1047         return snd_interval_refine(i, &list_range);
1048 }
1049
1050 EXPORT_SYMBOL(snd_interval_list);
1051
1052 /**
1053  * snd_interval_ranges - refine the interval value from the list of ranges
1054  * @i: the interval value to refine
1055  * @count: the number of elements in the list of ranges
1056  * @ranges: the ranges list
1057  * @mask: the bit-mask to evaluate
1058  *
1059  * Refines the interval value from the list of ranges.
1060  * When mask is non-zero, only the elements corresponding to bit 1 are
1061  * evaluated.
1062  *
1063  * Return: Positive if the value is changed, zero if it's not changed, or a
1064  * negative error code.
1065  */
1066 int snd_interval_ranges(struct snd_interval *i, unsigned int count,
1067                         const struct snd_interval *ranges, unsigned int mask)
1068 {
1069         unsigned int k;
1070         struct snd_interval range_union;
1071         struct snd_interval range;
1072
1073         if (!count) {
1074                 snd_interval_none(i);
1075                 return -EINVAL;
1076         }
1077         snd_interval_any(&range_union);
1078         range_union.min = UINT_MAX;
1079         range_union.max = 0;
1080         for (k = 0; k < count; k++) {
1081                 if (mask && !(mask & (1 << k)))
1082                         continue;
1083                 snd_interval_copy(&range, &ranges[k]);
1084                 if (snd_interval_refine(&range, i) < 0)
1085                         continue;
1086                 if (snd_interval_empty(&range))
1087                         continue;
1088
1089                 if (range.min < range_union.min) {
1090                         range_union.min = range.min;
1091                         range_union.openmin = 1;
1092                 }
1093                 if (range.min == range_union.min && !range.openmin)
1094                         range_union.openmin = 0;
1095                 if (range.max > range_union.max) {
1096                         range_union.max = range.max;
1097                         range_union.openmax = 1;
1098                 }
1099                 if (range.max == range_union.max && !range.openmax)
1100                         range_union.openmax = 0;
1101         }
1102         return snd_interval_refine(i, &range_union);
1103 }
1104 EXPORT_SYMBOL(snd_interval_ranges);
1105
1106 static int snd_interval_step(struct snd_interval *i, unsigned int step)
1107 {
1108         unsigned int n;
1109         int changed = 0;
1110         n = i->min % step;
1111         if (n != 0 || i->openmin) {
1112                 i->min += step - n;
1113                 i->openmin = 0;
1114                 changed = 1;
1115         }
1116         n = i->max % step;
1117         if (n != 0 || i->openmax) {
1118                 i->max -= n;
1119                 i->openmax = 0;
1120                 changed = 1;
1121         }
1122         if (snd_interval_checkempty(i)) {
1123                 i->empty = 1;
1124                 return -EINVAL;
1125         }
1126         return changed;
1127 }
1128
1129 /* Info constraints helpers */
1130
1131 /**
1132  * snd_pcm_hw_rule_add - add the hw-constraint rule
1133  * @runtime: the pcm runtime instance
1134  * @cond: condition bits
1135  * @var: the variable to evaluate
1136  * @func: the evaluation function
1137  * @private: the private data pointer passed to function
1138  * @dep: the dependent variables
1139  *
1140  * Return: Zero if successful, or a negative error code on failure.
1141  */
1142 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1143                         int var,
1144                         snd_pcm_hw_rule_func_t func, void *private,
1145                         int dep, ...)
1146 {
1147         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1148         struct snd_pcm_hw_rule *c;
1149         unsigned int k;
1150         va_list args;
1151         va_start(args, dep);
1152         if (constrs->rules_num >= constrs->rules_all) {
1153                 struct snd_pcm_hw_rule *new;
1154                 unsigned int new_rules = constrs->rules_all + 16;
1155                 new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1156                 if (!new) {
1157                         va_end(args);
1158                         return -ENOMEM;
1159                 }
1160                 if (constrs->rules) {
1161                         memcpy(new, constrs->rules,
1162                                constrs->rules_num * sizeof(*c));
1163                         kfree(constrs->rules);
1164                 }
1165                 constrs->rules = new;
1166                 constrs->rules_all = new_rules;
1167         }
1168         c = &constrs->rules[constrs->rules_num];
1169         c->cond = cond;
1170         c->func = func;
1171         c->var = var;
1172         c->private = private;
1173         k = 0;
1174         while (1) {
1175                 if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1176                         va_end(args);
1177                         return -EINVAL;
1178                 }
1179                 c->deps[k++] = dep;
1180                 if (dep < 0)
1181                         break;
1182                 dep = va_arg(args, int);
1183         }
1184         constrs->rules_num++;
1185         va_end(args);
1186         return 0;
1187 }
1188
1189 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1190
1191 /**
1192  * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1193  * @runtime: PCM runtime instance
1194  * @var: hw_params variable to apply the mask
1195  * @mask: the bitmap mask
1196  *
1197  * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1198  *
1199  * Return: Zero if successful, or a negative error code on failure.
1200  */
1201 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1202                                u_int32_t mask)
1203 {
1204         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1205         struct snd_mask *maskp = constrs_mask(constrs, var);
1206         *maskp->bits &= mask;
1207         memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1208         if (*maskp->bits == 0)
1209                 return -EINVAL;
1210         return 0;
1211 }
1212
1213 /**
1214  * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1215  * @runtime: PCM runtime instance
1216  * @var: hw_params variable to apply the mask
1217  * @mask: the 64bit bitmap mask
1218  *
1219  * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1220  *
1221  * Return: Zero if successful, or a negative error code on failure.
1222  */
1223 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1224                                  u_int64_t mask)
1225 {
1226         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1227         struct snd_mask *maskp = constrs_mask(constrs, var);
1228         maskp->bits[0] &= (u_int32_t)mask;
1229         maskp->bits[1] &= (u_int32_t)(mask >> 32);
1230         memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1231         if (! maskp->bits[0] && ! maskp->bits[1])
1232                 return -EINVAL;
1233         return 0;
1234 }
1235 EXPORT_SYMBOL(snd_pcm_hw_constraint_mask64);
1236
1237 /**
1238  * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1239  * @runtime: PCM runtime instance
1240  * @var: hw_params variable to apply the integer constraint
1241  *
1242  * Apply the constraint of integer to an interval parameter.
1243  *
1244  * Return: Positive if the value is changed, zero if it's not changed, or a
1245  * negative error code.
1246  */
1247 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1248 {
1249         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1250         return snd_interval_setinteger(constrs_interval(constrs, var));
1251 }
1252
1253 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1254
1255 /**
1256  * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1257  * @runtime: PCM runtime instance
1258  * @var: hw_params variable to apply the range
1259  * @min: the minimal value
1260  * @max: the maximal value
1261  *
1262  * Apply the min/max range constraint to an interval parameter.
1263  *
1264  * Return: Positive if the value is changed, zero if it's not changed, or a
1265  * negative error code.
1266  */
1267 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1268                                  unsigned int min, unsigned int max)
1269 {
1270         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1271         struct snd_interval t;
1272         t.min = min;
1273         t.max = max;
1274         t.openmin = t.openmax = 0;
1275         t.integer = 0;
1276         return snd_interval_refine(constrs_interval(constrs, var), &t);
1277 }
1278
1279 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1280
1281 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1282                                 struct snd_pcm_hw_rule *rule)
1283 {
1284         struct snd_pcm_hw_constraint_list *list = rule->private;
1285         return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1286 }
1287
1288
1289 /**
1290  * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1291  * @runtime: PCM runtime instance
1292  * @cond: condition bits
1293  * @var: hw_params variable to apply the list constraint
1294  * @l: list
1295  *
1296  * Apply the list of constraints to an interval parameter.
1297  *
1298  * Return: Zero if successful, or a negative error code on failure.
1299  */
1300 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1301                                unsigned int cond,
1302                                snd_pcm_hw_param_t var,
1303                                const struct snd_pcm_hw_constraint_list *l)
1304 {
1305         return snd_pcm_hw_rule_add(runtime, cond, var,
1306                                    snd_pcm_hw_rule_list, (void *)l,
1307                                    var, -1);
1308 }
1309
1310 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1311
1312 static int snd_pcm_hw_rule_ranges(struct snd_pcm_hw_params *params,
1313                                   struct snd_pcm_hw_rule *rule)
1314 {
1315         struct snd_pcm_hw_constraint_ranges *r = rule->private;
1316         return snd_interval_ranges(hw_param_interval(params, rule->var),
1317                                    r->count, r->ranges, r->mask);
1318 }
1319
1320
1321 /**
1322  * snd_pcm_hw_constraint_ranges - apply list of range constraints to a parameter
1323  * @runtime: PCM runtime instance
1324  * @cond: condition bits
1325  * @var: hw_params variable to apply the list of range constraints
1326  * @r: ranges
1327  *
1328  * Apply the list of range constraints to an interval parameter.
1329  *
1330  * Return: Zero if successful, or a negative error code on failure.
1331  */
1332 int snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime *runtime,
1333                                  unsigned int cond,
1334                                  snd_pcm_hw_param_t var,
1335                                  const struct snd_pcm_hw_constraint_ranges *r)
1336 {
1337         return snd_pcm_hw_rule_add(runtime, cond, var,
1338                                    snd_pcm_hw_rule_ranges, (void *)r,
1339                                    var, -1);
1340 }
1341 EXPORT_SYMBOL(snd_pcm_hw_constraint_ranges);
1342
1343 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1344                                    struct snd_pcm_hw_rule *rule)
1345 {
1346         const struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1347         unsigned int num = 0, den = 0;
1348         int err;
1349         err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1350                                   r->nrats, r->rats, &num, &den);
1351         if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1352                 params->rate_num = num;
1353                 params->rate_den = den;
1354         }
1355         return err;
1356 }
1357
1358 /**
1359  * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1360  * @runtime: PCM runtime instance
1361  * @cond: condition bits
1362  * @var: hw_params variable to apply the ratnums constraint
1363  * @r: struct snd_ratnums constriants
1364  *
1365  * Return: Zero if successful, or a negative error code on failure.
1366  */
1367 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1368                                   unsigned int cond,
1369                                   snd_pcm_hw_param_t var,
1370                                   const struct snd_pcm_hw_constraint_ratnums *r)
1371 {
1372         return snd_pcm_hw_rule_add(runtime, cond, var,
1373                                    snd_pcm_hw_rule_ratnums, (void *)r,
1374                                    var, -1);
1375 }
1376
1377 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1378
1379 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1380                                    struct snd_pcm_hw_rule *rule)
1381 {
1382         const struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1383         unsigned int num = 0, den = 0;
1384         int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1385                                   r->nrats, r->rats, &num, &den);
1386         if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1387                 params->rate_num = num;
1388                 params->rate_den = den;
1389         }
1390         return err;
1391 }
1392
1393 /**
1394  * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1395  * @runtime: PCM runtime instance
1396  * @cond: condition bits
1397  * @var: hw_params variable to apply the ratdens constraint
1398  * @r: struct snd_ratdens constriants
1399  *
1400  * Return: Zero if successful, or a negative error code on failure.
1401  */
1402 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1403                                   unsigned int cond,
1404                                   snd_pcm_hw_param_t var,
1405                                   const struct snd_pcm_hw_constraint_ratdens *r)
1406 {
1407         return snd_pcm_hw_rule_add(runtime, cond, var,
1408                                    snd_pcm_hw_rule_ratdens, (void *)r,
1409                                    var, -1);
1410 }
1411
1412 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1413
1414 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1415                                   struct snd_pcm_hw_rule *rule)
1416 {
1417         unsigned int l = (unsigned long) rule->private;
1418         int width = l & 0xffff;
1419         unsigned int msbits = l >> 16;
1420         const struct snd_interval *i =
1421                 hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1422
1423         if (!snd_interval_single(i))
1424                 return 0;
1425
1426         if ((snd_interval_value(i) == width) ||
1427             (width == 0 && snd_interval_value(i) > msbits))
1428                 params->msbits = min_not_zero(params->msbits, msbits);
1429
1430         return 0;
1431 }
1432
1433 /**
1434  * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1435  * @runtime: PCM runtime instance
1436  * @cond: condition bits
1437  * @width: sample bits width
1438  * @msbits: msbits width
1439  *
1440  * This constraint will set the number of most significant bits (msbits) if a
1441  * sample format with the specified width has been select. If width is set to 0
1442  * the msbits will be set for any sample format with a width larger than the
1443  * specified msbits.
1444  *
1445  * Return: Zero if successful, or a negative error code on failure.
1446  */
1447 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1448                                  unsigned int cond,
1449                                  unsigned int width,
1450                                  unsigned int msbits)
1451 {
1452         unsigned long l = (msbits << 16) | width;
1453         return snd_pcm_hw_rule_add(runtime, cond, -1,
1454                                     snd_pcm_hw_rule_msbits,
1455                                     (void*) l,
1456                                     SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1457 }
1458
1459 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1460
1461 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1462                                 struct snd_pcm_hw_rule *rule)
1463 {
1464         unsigned long step = (unsigned long) rule->private;
1465         return snd_interval_step(hw_param_interval(params, rule->var), step);
1466 }
1467
1468 /**
1469  * snd_pcm_hw_constraint_step - add a hw constraint step rule
1470  * @runtime: PCM runtime instance
1471  * @cond: condition bits
1472  * @var: hw_params variable to apply the step constraint
1473  * @step: step size
1474  *
1475  * Return: Zero if successful, or a negative error code on failure.
1476  */
1477 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1478                                unsigned int cond,
1479                                snd_pcm_hw_param_t var,
1480                                unsigned long step)
1481 {
1482         return snd_pcm_hw_rule_add(runtime, cond, var,
1483                                    snd_pcm_hw_rule_step, (void *) step,
1484                                    var, -1);
1485 }
1486
1487 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1488
1489 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1490 {
1491         static unsigned int pow2_sizes[] = {
1492                 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1493                 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1494                 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1495                 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1496         };
1497         return snd_interval_list(hw_param_interval(params, rule->var),
1498                                  ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1499 }
1500
1501 /**
1502  * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1503  * @runtime: PCM runtime instance
1504  * @cond: condition bits
1505  * @var: hw_params variable to apply the power-of-2 constraint
1506  *
1507  * Return: Zero if successful, or a negative error code on failure.
1508  */
1509 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1510                                unsigned int cond,
1511                                snd_pcm_hw_param_t var)
1512 {
1513         return snd_pcm_hw_rule_add(runtime, cond, var,
1514                                    snd_pcm_hw_rule_pow2, NULL,
1515                                    var, -1);
1516 }
1517
1518 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1519
1520 static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1521                                            struct snd_pcm_hw_rule *rule)
1522 {
1523         unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1524         struct snd_interval *rate;
1525
1526         rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1527         return snd_interval_list(rate, 1, &base_rate, 0);
1528 }
1529
1530 /**
1531  * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1532  * @runtime: PCM runtime instance
1533  * @base_rate: the rate at which the hardware does not resample
1534  *
1535  * Return: Zero if successful, or a negative error code on failure.
1536  */
1537 int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1538                                unsigned int base_rate)
1539 {
1540         return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1541                                    SNDRV_PCM_HW_PARAM_RATE,
1542                                    snd_pcm_hw_rule_noresample_func,
1543                                    (void *)(uintptr_t)base_rate,
1544                                    SNDRV_PCM_HW_PARAM_RATE, -1);
1545 }
1546 EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1547
1548 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1549                                   snd_pcm_hw_param_t var)
1550 {
1551         if (hw_is_mask(var)) {
1552                 snd_mask_any(hw_param_mask(params, var));
1553                 params->cmask |= 1 << var;
1554                 params->rmask |= 1 << var;
1555                 return;
1556         }
1557         if (hw_is_interval(var)) {
1558                 snd_interval_any(hw_param_interval(params, var));
1559                 params->cmask |= 1 << var;
1560                 params->rmask |= 1 << var;
1561                 return;
1562         }
1563         snd_BUG();
1564 }
1565
1566 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1567 {
1568         unsigned int k;
1569         memset(params, 0, sizeof(*params));
1570         for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1571                 _snd_pcm_hw_param_any(params, k);
1572         for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1573                 _snd_pcm_hw_param_any(params, k);
1574         params->info = ~0U;
1575 }
1576
1577 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1578
1579 /**
1580  * snd_pcm_hw_param_value - return @params field @var value
1581  * @params: the hw_params instance
1582  * @var: parameter to retrieve
1583  * @dir: pointer to the direction (-1,0,1) or %NULL
1584  *
1585  * Return: The value for field @var if it's fixed in configuration space
1586  * defined by @params. -%EINVAL otherwise.
1587  */
1588 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1589                            snd_pcm_hw_param_t var, int *dir)
1590 {
1591         if (hw_is_mask(var)) {
1592                 const struct snd_mask *mask = hw_param_mask_c(params, var);
1593                 if (!snd_mask_single(mask))
1594                         return -EINVAL;
1595                 if (dir)
1596                         *dir = 0;
1597                 return snd_mask_value(mask);
1598         }
1599         if (hw_is_interval(var)) {
1600                 const struct snd_interval *i = hw_param_interval_c(params, var);
1601                 if (!snd_interval_single(i))
1602                         return -EINVAL;
1603                 if (dir)
1604                         *dir = i->openmin;
1605                 return snd_interval_value(i);
1606         }
1607         return -EINVAL;
1608 }
1609
1610 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1611
1612 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1613                                 snd_pcm_hw_param_t var)
1614 {
1615         if (hw_is_mask(var)) {
1616                 snd_mask_none(hw_param_mask(params, var));
1617                 params->cmask |= 1 << var;
1618                 params->rmask |= 1 << var;
1619         } else if (hw_is_interval(var)) {
1620                 snd_interval_none(hw_param_interval(params, var));
1621                 params->cmask |= 1 << var;
1622                 params->rmask |= 1 << var;
1623         } else {
1624                 snd_BUG();
1625         }
1626 }
1627
1628 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1629
1630 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1631                                    snd_pcm_hw_param_t var)
1632 {
1633         int changed;
1634         if (hw_is_mask(var))
1635                 changed = snd_mask_refine_first(hw_param_mask(params, var));
1636         else if (hw_is_interval(var))
1637                 changed = snd_interval_refine_first(hw_param_interval(params, var));
1638         else
1639                 return -EINVAL;
1640         if (changed) {
1641                 params->cmask |= 1 << var;
1642                 params->rmask |= 1 << var;
1643         }
1644         return changed;
1645 }
1646
1647
1648 /**
1649  * snd_pcm_hw_param_first - refine config space and return minimum value
1650  * @pcm: PCM instance
1651  * @params: the hw_params instance
1652  * @var: parameter to retrieve
1653  * @dir: pointer to the direction (-1,0,1) or %NULL
1654  *
1655  * Inside configuration space defined by @params remove from @var all
1656  * values > minimum. Reduce configuration space accordingly.
1657  *
1658  * Return: The minimum, or a negative error code on failure.
1659  */
1660 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1661                            struct snd_pcm_hw_params *params,
1662                            snd_pcm_hw_param_t var, int *dir)
1663 {
1664         int changed = _snd_pcm_hw_param_first(params, var);
1665         if (changed < 0)
1666                 return changed;
1667         if (params->rmask) {
1668                 int err = snd_pcm_hw_refine(pcm, params);
1669                 if (snd_BUG_ON(err < 0))
1670                         return err;
1671         }
1672         return snd_pcm_hw_param_value(params, var, dir);
1673 }
1674
1675 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1676
1677 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1678                                   snd_pcm_hw_param_t var)
1679 {
1680         int changed;
1681         if (hw_is_mask(var))
1682                 changed = snd_mask_refine_last(hw_param_mask(params, var));
1683         else if (hw_is_interval(var))
1684                 changed = snd_interval_refine_last(hw_param_interval(params, var));
1685         else
1686                 return -EINVAL;
1687         if (changed) {
1688                 params->cmask |= 1 << var;
1689                 params->rmask |= 1 << var;
1690         }
1691         return changed;
1692 }
1693
1694
1695 /**
1696  * snd_pcm_hw_param_last - refine config space and return maximum value
1697  * @pcm: PCM instance
1698  * @params: the hw_params instance
1699  * @var: parameter to retrieve
1700  * @dir: pointer to the direction (-1,0,1) or %NULL
1701  *
1702  * Inside configuration space defined by @params remove from @var all
1703  * values < maximum. Reduce configuration space accordingly.
1704  *
1705  * Return: The maximum, or a negative error code on failure.
1706  */
1707 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1708                           struct snd_pcm_hw_params *params,
1709                           snd_pcm_hw_param_t var, int *dir)
1710 {
1711         int changed = _snd_pcm_hw_param_last(params, var);
1712         if (changed < 0)
1713                 return changed;
1714         if (params->rmask) {
1715                 int err = snd_pcm_hw_refine(pcm, params);
1716                 if (snd_BUG_ON(err < 0))
1717                         return err;
1718         }
1719         return snd_pcm_hw_param_value(params, var, dir);
1720 }
1721
1722 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1723
1724 /**
1725  * snd_pcm_hw_param_choose - choose a configuration defined by @params
1726  * @pcm: PCM instance
1727  * @params: the hw_params instance
1728  *
1729  * Choose one configuration from configuration space defined by @params.
1730  * The configuration chosen is that obtained fixing in this order:
1731  * first access, first format, first subformat, min channels,
1732  * min rate, min period time, max buffer size, min tick time
1733  *
1734  * Return: Zero if successful, or a negative error code on failure.
1735  */
1736 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1737                              struct snd_pcm_hw_params *params)
1738 {
1739         static const int vars[] = {
1740                 SNDRV_PCM_HW_PARAM_ACCESS,
1741                 SNDRV_PCM_HW_PARAM_FORMAT,
1742                 SNDRV_PCM_HW_PARAM_SUBFORMAT,
1743                 SNDRV_PCM_HW_PARAM_CHANNELS,
1744                 SNDRV_PCM_HW_PARAM_RATE,
1745                 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1746                 SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1747                 SNDRV_PCM_HW_PARAM_TICK_TIME,
1748                 -1
1749         };
1750         const int *v;
1751         int err;
1752
1753         for (v = vars; *v != -1; v++) {
1754                 if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1755                         err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1756                 else
1757                         err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1758                 if (snd_BUG_ON(err < 0))
1759                         return err;
1760         }
1761         return 0;
1762 }
1763
1764 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1765                                    void *arg)
1766 {
1767         struct snd_pcm_runtime *runtime = substream->runtime;
1768         unsigned long flags;
1769         snd_pcm_stream_lock_irqsave(substream, flags);
1770         if (snd_pcm_running(substream) &&
1771             snd_pcm_update_hw_ptr(substream) >= 0)
1772                 runtime->status->hw_ptr %= runtime->buffer_size;
1773         else {
1774                 runtime->status->hw_ptr = 0;
1775                 runtime->hw_ptr_wrap = 0;
1776         }
1777         snd_pcm_stream_unlock_irqrestore(substream, flags);
1778         return 0;
1779 }
1780
1781 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1782                                           void *arg)
1783 {
1784         struct snd_pcm_channel_info *info = arg;
1785         struct snd_pcm_runtime *runtime = substream->runtime;
1786         int width;
1787         if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1788                 info->offset = -1;
1789                 return 0;
1790         }
1791         width = snd_pcm_format_physical_width(runtime->format);
1792         if (width < 0)
1793                 return width;
1794         info->offset = 0;
1795         switch (runtime->access) {
1796         case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1797         case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1798                 info->first = info->channel * width;
1799                 info->step = runtime->channels * width;
1800                 break;
1801         case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1802         case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1803         {
1804                 size_t size = runtime->dma_bytes / runtime->channels;
1805                 info->first = info->channel * size * 8;
1806                 info->step = width;
1807                 break;
1808         }
1809         default:
1810                 snd_BUG();
1811                 break;
1812         }
1813         return 0;
1814 }
1815
1816 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1817                                        void *arg)
1818 {
1819         struct snd_pcm_hw_params *params = arg;
1820         snd_pcm_format_t format;
1821         int channels;
1822         ssize_t frame_size;
1823
1824         params->fifo_size = substream->runtime->hw.fifo_size;
1825         if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1826                 format = params_format(params);
1827                 channels = params_channels(params);
1828                 frame_size = snd_pcm_format_size(format, channels);
1829                 if (frame_size > 0)
1830                         params->fifo_size /= (unsigned)frame_size;
1831         }
1832         return 0;
1833 }
1834
1835 /**
1836  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1837  * @substream: the pcm substream instance
1838  * @cmd: ioctl command
1839  * @arg: ioctl argument
1840  *
1841  * Processes the generic ioctl commands for PCM.
1842  * Can be passed as the ioctl callback for PCM ops.
1843  *
1844  * Return: Zero if successful, or a negative error code on failure.
1845  */
1846 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1847                       unsigned int cmd, void *arg)
1848 {
1849         switch (cmd) {
1850         case SNDRV_PCM_IOCTL1_INFO:
1851                 return 0;
1852         case SNDRV_PCM_IOCTL1_RESET:
1853                 return snd_pcm_lib_ioctl_reset(substream, arg);
1854         case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1855                 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1856         case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1857                 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1858         }
1859         return -ENXIO;
1860 }
1861
1862 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1863
1864 /**
1865  * snd_pcm_period_elapsed - update the pcm status for the next period
1866  * @substream: the pcm substream instance
1867  *
1868  * This function is called from the interrupt handler when the
1869  * PCM has processed the period size.  It will update the current
1870  * pointer, wake up sleepers, etc.
1871  *
1872  * Even if more than one periods have elapsed since the last call, you
1873  * have to call this only once.
1874  */
1875 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1876 {
1877         struct snd_pcm_runtime *runtime;
1878         unsigned long flags;
1879
1880         if (PCM_RUNTIME_CHECK(substream))
1881                 return;
1882         runtime = substream->runtime;
1883
1884         snd_pcm_stream_lock_irqsave(substream, flags);
1885         if (!snd_pcm_running(substream) ||
1886             snd_pcm_update_hw_ptr0(substream, 1) < 0)
1887                 goto _end;
1888
1889 #ifdef CONFIG_SND_PCM_TIMER
1890         if (substream->timer_running)
1891                 snd_timer_interrupt(substream->timer, 1);
1892 #endif
1893  _end:
1894         kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1895         snd_pcm_stream_unlock_irqrestore(substream, flags);
1896 }
1897
1898 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1899
1900 /*
1901  * Wait until avail_min data becomes available
1902  * Returns a negative error code if any error occurs during operation.
1903  * The available space is stored on availp.  When err = 0 and avail = 0
1904  * on the capture stream, it indicates the stream is in DRAINING state.
1905  */
1906 static int wait_for_avail(struct snd_pcm_substream *substream,
1907                               snd_pcm_uframes_t *availp)
1908 {
1909         struct snd_pcm_runtime *runtime = substream->runtime;
1910         int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1911         wait_queue_t wait;
1912         int err = 0;
1913         snd_pcm_uframes_t avail = 0;
1914         long wait_time, tout;
1915
1916         init_waitqueue_entry(&wait, current);
1917         set_current_state(TASK_INTERRUPTIBLE);
1918         add_wait_queue(&runtime->tsleep, &wait);
1919
1920         if (runtime->no_period_wakeup)
1921                 wait_time = MAX_SCHEDULE_TIMEOUT;
1922         else {
1923                 wait_time = 10;
1924                 if (runtime->rate) {
1925                         long t = runtime->period_size * 2 / runtime->rate;
1926                         wait_time = max(t, wait_time);
1927                 }
1928                 wait_time = msecs_to_jiffies(wait_time * 1000);
1929         }
1930
1931         for (;;) {
1932                 if (signal_pending(current)) {
1933                         err = -ERESTARTSYS;
1934                         break;
1935                 }
1936
1937                 /*
1938                  * We need to check if space became available already
1939                  * (and thus the wakeup happened already) first to close
1940                  * the race of space already having become available.
1941                  * This check must happen after been added to the waitqueue
1942                  * and having current state be INTERRUPTIBLE.
1943                  */
1944                 if (is_playback)
1945                         avail = snd_pcm_playback_avail(runtime);
1946                 else
1947                         avail = snd_pcm_capture_avail(runtime);
1948                 if (avail >= runtime->twake)
1949                         break;
1950                 snd_pcm_stream_unlock_irq(substream);
1951
1952                 tout = schedule_timeout(wait_time);
1953
1954                 snd_pcm_stream_lock_irq(substream);
1955                 set_current_state(TASK_INTERRUPTIBLE);
1956                 switch (runtime->status->state) {
1957                 case SNDRV_PCM_STATE_SUSPENDED:
1958                         err = -ESTRPIPE;
1959                         goto _endloop;
1960                 case SNDRV_PCM_STATE_XRUN:
1961                         err = -EPIPE;
1962                         goto _endloop;
1963                 case SNDRV_PCM_STATE_DRAINING:
1964                         if (is_playback)
1965                                 err = -EPIPE;
1966                         else
1967                                 avail = 0; /* indicate draining */
1968                         goto _endloop;
1969                 case SNDRV_PCM_STATE_OPEN:
1970                 case SNDRV_PCM_STATE_SETUP:
1971                 case SNDRV_PCM_STATE_DISCONNECTED:
1972                         err = -EBADFD;
1973                         goto _endloop;
1974                 case SNDRV_PCM_STATE_PAUSED:
1975                         continue;
1976                 }
1977                 if (!tout) {
1978                         pcm_dbg(substream->pcm,
1979                                 "%s write error (DMA or IRQ trouble?)\n",
1980                                 is_playback ? "playback" : "capture");
1981                         err = -EIO;
1982                         break;
1983                 }
1984         }
1985  _endloop:
1986         set_current_state(TASK_RUNNING);
1987         remove_wait_queue(&runtime->tsleep, &wait);
1988         *availp = avail;
1989         return err;
1990 }
1991
1992 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1993                                       unsigned int hwoff,
1994                                       unsigned long data, unsigned int off,
1995                                       snd_pcm_uframes_t frames)
1996 {
1997         struct snd_pcm_runtime *runtime = substream->runtime;
1998         int err;
1999         char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2000         if (substream->ops->copy) {
2001                 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2002                         return err;
2003         } else {
2004                 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2005                 if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
2006                         return -EFAULT;
2007         }
2008         return 0;
2009 }
2010
2011 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
2012                           unsigned long data, unsigned int off,
2013                           snd_pcm_uframes_t size);
2014
2015 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
2016                                             unsigned long data,
2017                                             snd_pcm_uframes_t size,
2018                                             int nonblock,
2019                                             transfer_f transfer)
2020 {
2021         struct snd_pcm_runtime *runtime = substream->runtime;
2022         snd_pcm_uframes_t xfer = 0;
2023         snd_pcm_uframes_t offset = 0;
2024         snd_pcm_uframes_t avail;
2025         int err = 0;
2026
2027         if (size == 0)
2028                 return 0;
2029
2030         snd_pcm_stream_lock_irq(substream);
2031         switch (runtime->status->state) {
2032         case SNDRV_PCM_STATE_PREPARED:
2033         case SNDRV_PCM_STATE_RUNNING:
2034         case SNDRV_PCM_STATE_PAUSED:
2035                 break;
2036         case SNDRV_PCM_STATE_XRUN:
2037                 err = -EPIPE;
2038                 goto _end_unlock;
2039         case SNDRV_PCM_STATE_SUSPENDED:
2040                 err = -ESTRPIPE;
2041                 goto _end_unlock;
2042         default:
2043                 err = -EBADFD;
2044                 goto _end_unlock;
2045         }
2046
2047         runtime->twake = runtime->control->avail_min ? : 1;
2048         if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2049                 snd_pcm_update_hw_ptr(substream);
2050         avail = snd_pcm_playback_avail(runtime);
2051         while (size > 0) {
2052                 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2053                 snd_pcm_uframes_t cont;
2054                 if (!avail) {
2055                         if (nonblock) {
2056                                 err = -EAGAIN;
2057                                 goto _end_unlock;
2058                         }
2059                         runtime->twake = min_t(snd_pcm_uframes_t, size,
2060                                         runtime->control->avail_min ? : 1);
2061                         err = wait_for_avail(substream, &avail);
2062                         if (err < 0)
2063                                 goto _end_unlock;
2064                 }
2065                 frames = size > avail ? avail : size;
2066                 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2067                 if (frames > cont)
2068                         frames = cont;
2069                 if (snd_BUG_ON(!frames)) {
2070                         runtime->twake = 0;
2071                         snd_pcm_stream_unlock_irq(substream);
2072                         return -EINVAL;
2073                 }
2074                 appl_ptr = runtime->control->appl_ptr;
2075                 appl_ofs = appl_ptr % runtime->buffer_size;
2076                 snd_pcm_stream_unlock_irq(substream);
2077                 err = transfer(substream, appl_ofs, data, offset, frames);
2078                 snd_pcm_stream_lock_irq(substream);
2079                 if (err < 0)
2080                         goto _end_unlock;
2081                 switch (runtime->status->state) {
2082                 case SNDRV_PCM_STATE_XRUN:
2083                         err = -EPIPE;
2084                         goto _end_unlock;
2085                 case SNDRV_PCM_STATE_SUSPENDED:
2086                         err = -ESTRPIPE;
2087                         goto _end_unlock;
2088                 default:
2089                         break;
2090                 }
2091                 appl_ptr += frames;
2092                 if (appl_ptr >= runtime->boundary)
2093                         appl_ptr -= runtime->boundary;
2094                 runtime->control->appl_ptr = appl_ptr;
2095                 if (substream->ops->ack)
2096                         substream->ops->ack(substream);
2097
2098                 offset += frames;
2099                 size -= frames;
2100                 xfer += frames;
2101                 avail -= frames;
2102                 if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
2103                     snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
2104                         err = snd_pcm_start(substream);
2105                         if (err < 0)
2106                                 goto _end_unlock;
2107                 }
2108         }
2109  _end_unlock:
2110         runtime->twake = 0;
2111         if (xfer > 0 && err >= 0)
2112                 snd_pcm_update_state(substream, runtime);
2113         snd_pcm_stream_unlock_irq(substream);
2114         return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2115 }
2116
2117 /* sanity-check for read/write methods */
2118 static int pcm_sanity_check(struct snd_pcm_substream *substream)
2119 {
2120         struct snd_pcm_runtime *runtime;
2121         if (PCM_RUNTIME_CHECK(substream))
2122                 return -ENXIO;
2123         runtime = substream->runtime;
2124         if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
2125                 return -EINVAL;
2126         if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2127                 return -EBADFD;
2128         return 0;
2129 }
2130
2131 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
2132 {
2133         struct snd_pcm_runtime *runtime;
2134         int nonblock;
2135         int err;
2136
2137         err = pcm_sanity_check(substream);
2138         if (err < 0)
2139                 return err;
2140         runtime = substream->runtime;
2141         nonblock = !!(substream->f_flags & O_NONBLOCK);
2142
2143         if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2144             runtime->channels > 1)
2145                 return -EINVAL;
2146         return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
2147                                   snd_pcm_lib_write_transfer);
2148 }
2149
2150 EXPORT_SYMBOL(snd_pcm_lib_write);
2151
2152 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
2153                                        unsigned int hwoff,
2154                                        unsigned long data, unsigned int off,
2155                                        snd_pcm_uframes_t frames)
2156 {
2157         struct snd_pcm_runtime *runtime = substream->runtime;
2158         int err;
2159         void __user **bufs = (void __user **)data;
2160         int channels = runtime->channels;
2161         int c;
2162         if (substream->ops->copy) {
2163                 if (snd_BUG_ON(!substream->ops->silence))
2164                         return -EINVAL;
2165                 for (c = 0; c < channels; ++c, ++bufs) {
2166                         if (*bufs == NULL) {
2167                                 if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
2168                                         return err;
2169                         } else {
2170                                 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2171                                 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2172                                         return err;
2173                         }
2174                 }
2175         } else {
2176                 /* default transfer behaviour */
2177                 size_t dma_csize = runtime->dma_bytes / channels;
2178                 for (c = 0; c < channels; ++c, ++bufs) {
2179                         char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2180                         if (*bufs == NULL) {
2181                                 snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
2182                         } else {
2183                                 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2184                                 if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
2185                                         return -EFAULT;
2186                         }
2187                 }
2188         }
2189         return 0;
2190 }
2191
2192 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
2193                                      void __user **bufs,
2194                                      snd_pcm_uframes_t frames)
2195 {
2196         struct snd_pcm_runtime *runtime;
2197         int nonblock;
2198         int err;
2199
2200         err = pcm_sanity_check(substream);
2201         if (err < 0)
2202                 return err;
2203         runtime = substream->runtime;
2204         nonblock = !!(substream->f_flags & O_NONBLOCK);
2205
2206         if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2207                 return -EINVAL;
2208         return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2209                                   nonblock, snd_pcm_lib_writev_transfer);
2210 }
2211
2212 EXPORT_SYMBOL(snd_pcm_lib_writev);
2213
2214 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
2215                                      unsigned int hwoff,
2216                                      unsigned long data, unsigned int off,
2217                                      snd_pcm_uframes_t frames)
2218 {
2219         struct snd_pcm_runtime *runtime = substream->runtime;
2220         int err;
2221         char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2222         if (substream->ops->copy) {
2223                 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2224                         return err;
2225         } else {
2226                 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2227                 if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2228                         return -EFAULT;
2229         }
2230         return 0;
2231 }
2232
2233 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2234                                            unsigned long data,
2235                                            snd_pcm_uframes_t size,
2236                                            int nonblock,
2237                                            transfer_f transfer)
2238 {
2239         struct snd_pcm_runtime *runtime = substream->runtime;
2240         snd_pcm_uframes_t xfer = 0;
2241         snd_pcm_uframes_t offset = 0;
2242         snd_pcm_uframes_t avail;
2243         int err = 0;
2244
2245         if (size == 0)
2246                 return 0;
2247
2248         snd_pcm_stream_lock_irq(substream);
2249         switch (runtime->status->state) {
2250         case SNDRV_PCM_STATE_PREPARED:
2251                 if (size >= runtime->start_threshold) {
2252                         err = snd_pcm_start(substream);
2253                         if (err < 0)
2254                                 goto _end_unlock;
2255                 }
2256                 break;
2257         case SNDRV_PCM_STATE_DRAINING:
2258         case SNDRV_PCM_STATE_RUNNING:
2259         case SNDRV_PCM_STATE_PAUSED:
2260                 break;
2261         case SNDRV_PCM_STATE_XRUN:
2262                 err = -EPIPE;
2263                 goto _end_unlock;
2264         case SNDRV_PCM_STATE_SUSPENDED:
2265                 err = -ESTRPIPE;
2266                 goto _end_unlock;
2267         default:
2268                 err = -EBADFD;
2269                 goto _end_unlock;
2270         }
2271
2272         runtime->twake = runtime->control->avail_min ? : 1;
2273         if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2274                 snd_pcm_update_hw_ptr(substream);
2275         avail = snd_pcm_capture_avail(runtime);
2276         while (size > 0) {
2277                 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2278                 snd_pcm_uframes_t cont;
2279                 if (!avail) {
2280                         if (runtime->status->state ==
2281                             SNDRV_PCM_STATE_DRAINING) {
2282                                 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2283                                 goto _end_unlock;
2284                         }
2285                         if (nonblock) {
2286                                 err = -EAGAIN;
2287                                 goto _end_unlock;
2288                         }
2289                         runtime->twake = min_t(snd_pcm_uframes_t, size,
2290                                         runtime->control->avail_min ? : 1);
2291                         err = wait_for_avail(substream, &avail);
2292                         if (err < 0)
2293                                 goto _end_unlock;
2294                         if (!avail)
2295                                 continue; /* draining */
2296                 }
2297                 frames = size > avail ? avail : size;
2298                 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2299                 if (frames > cont)
2300                         frames = cont;
2301                 if (snd_BUG_ON(!frames)) {
2302                         runtime->twake = 0;
2303                         snd_pcm_stream_unlock_irq(substream);
2304                         return -EINVAL;
2305                 }
2306                 appl_ptr = runtime->control->appl_ptr;
2307                 appl_ofs = appl_ptr % runtime->buffer_size;
2308                 snd_pcm_stream_unlock_irq(substream);
2309                 err = transfer(substream, appl_ofs, data, offset, frames);
2310                 snd_pcm_stream_lock_irq(substream);
2311                 if (err < 0)
2312                         goto _end_unlock;
2313                 switch (runtime->status->state) {
2314                 case SNDRV_PCM_STATE_XRUN:
2315                         err = -EPIPE;
2316                         goto _end_unlock;
2317                 case SNDRV_PCM_STATE_SUSPENDED:
2318                         err = -ESTRPIPE;
2319                         goto _end_unlock;
2320                 default:
2321                         break;
2322                 }
2323                 appl_ptr += frames;
2324                 if (appl_ptr >= runtime->boundary)
2325                         appl_ptr -= runtime->boundary;
2326                 runtime->control->appl_ptr = appl_ptr;
2327                 if (substream->ops->ack)
2328                         substream->ops->ack(substream);
2329
2330                 offset += frames;
2331                 size -= frames;
2332                 xfer += frames;
2333                 avail -= frames;
2334         }
2335  _end_unlock:
2336         runtime->twake = 0;
2337         if (xfer > 0 && err >= 0)
2338                 snd_pcm_update_state(substream, runtime);
2339         snd_pcm_stream_unlock_irq(substream);
2340         return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2341 }
2342
2343 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2344 {
2345         struct snd_pcm_runtime *runtime;
2346         int nonblock;
2347         int err;
2348
2349         err = pcm_sanity_check(substream);
2350         if (err < 0)
2351                 return err;
2352         runtime = substream->runtime;
2353         nonblock = !!(substream->f_flags & O_NONBLOCK);
2354         if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2355                 return -EINVAL;
2356         return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2357 }
2358
2359 EXPORT_SYMBOL(snd_pcm_lib_read);
2360
2361 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2362                                       unsigned int hwoff,
2363                                       unsigned long data, unsigned int off,
2364                                       snd_pcm_uframes_t frames)
2365 {
2366         struct snd_pcm_runtime *runtime = substream->runtime;
2367         int err;
2368         void __user **bufs = (void __user **)data;
2369         int channels = runtime->channels;
2370         int c;
2371         if (substream->ops->copy) {
2372                 for (c = 0; c < channels; ++c, ++bufs) {
2373                         char __user *buf;
2374                         if (*bufs == NULL)
2375                                 continue;
2376                         buf = *bufs + samples_to_bytes(runtime, off);
2377                         if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2378                                 return err;
2379                 }
2380         } else {
2381                 snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2382                 for (c = 0; c < channels; ++c, ++bufs) {
2383                         char *hwbuf;
2384                         char __user *buf;
2385                         if (*bufs == NULL)
2386                                 continue;
2387
2388                         hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2389                         buf = *bufs + samples_to_bytes(runtime, off);
2390                         if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2391                                 return -EFAULT;
2392                 }
2393         }
2394         return 0;
2395 }
2396
2397 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2398                                     void __user **bufs,
2399                                     snd_pcm_uframes_t frames)
2400 {
2401         struct snd_pcm_runtime *runtime;
2402         int nonblock;
2403         int err;
2404
2405         err = pcm_sanity_check(substream);
2406         if (err < 0)
2407                 return err;
2408         runtime = substream->runtime;
2409         if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2410                 return -EBADFD;
2411
2412         nonblock = !!(substream->f_flags & O_NONBLOCK);
2413         if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2414                 return -EINVAL;
2415         return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2416 }
2417
2418 EXPORT_SYMBOL(snd_pcm_lib_readv);
2419
2420 /*
2421  * standard channel mapping helpers
2422  */
2423
2424 /* default channel maps for multi-channel playbacks, up to 8 channels */
2425 const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2426         { .channels = 1,
2427           .map = { SNDRV_CHMAP_MONO } },
2428         { .channels = 2,
2429           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2430         { .channels = 4,
2431           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2432                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2433         { .channels = 6,
2434           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2435                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2436                    SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2437         { .channels = 8,
2438           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2439                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2440                    SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2441                    SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2442         { }
2443 };
2444 EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2445
2446 /* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2447 const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2448         { .channels = 1,
2449           .map = { SNDRV_CHMAP_MONO } },
2450         { .channels = 2,
2451           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2452         { .channels = 4,
2453           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2454                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2455         { .channels = 6,
2456           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2457                    SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2458                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2459         { .channels = 8,
2460           .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2461                    SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2462                    SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2463                    SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2464         { }
2465 };
2466 EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2467
2468 static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2469 {
2470         if (ch > info->max_channels)
2471                 return false;
2472         return !info->channel_mask || (info->channel_mask & (1U << ch));
2473 }
2474
2475 static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2476                               struct snd_ctl_elem_info *uinfo)
2477 {
2478         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2479
2480         uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2481         uinfo->count = 0;
2482         uinfo->count = info->max_channels;
2483         uinfo->value.integer.min = 0;
2484         uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2485         return 0;
2486 }
2487
2488 /* get callback for channel map ctl element
2489  * stores the channel position firstly matching with the current channels
2490  */
2491 static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2492                              struct snd_ctl_elem_value *ucontrol)
2493 {
2494         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2495         unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2496         struct snd_pcm_substream *substream;
2497         const struct snd_pcm_chmap_elem *map;
2498
2499         if (snd_BUG_ON(!info->chmap))
2500                 return -EINVAL;
2501         substream = snd_pcm_chmap_substream(info, idx);
2502         if (!substream)
2503                 return -ENODEV;
2504         memset(ucontrol->value.integer.value, 0,
2505                sizeof(ucontrol->value.integer.value));
2506         if (!substream->runtime)
2507                 return 0; /* no channels set */
2508         for (map = info->chmap; map->channels; map++) {
2509                 int i;
2510                 if (map->channels == substream->runtime->channels &&
2511                     valid_chmap_channels(info, map->channels)) {
2512                         for (i = 0; i < map->channels; i++)
2513                                 ucontrol->value.integer.value[i] = map->map[i];
2514                         return 0;
2515                 }
2516         }
2517         return -EINVAL;
2518 }
2519
2520 /* tlv callback for channel map ctl element
2521  * expands the pre-defined channel maps in a form of TLV
2522  */
2523 static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2524                              unsigned int size, unsigned int __user *tlv)
2525 {
2526         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2527         const struct snd_pcm_chmap_elem *map;
2528         unsigned int __user *dst;
2529         int c, count = 0;
2530
2531         if (snd_BUG_ON(!info->chmap))
2532                 return -EINVAL;
2533         if (size < 8)
2534                 return -ENOMEM;
2535         if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2536                 return -EFAULT;
2537         size -= 8;
2538         dst = tlv + 2;
2539         for (map = info->chmap; map->channels; map++) {
2540                 int chs_bytes = map->channels * 4;
2541                 if (!valid_chmap_channels(info, map->channels))
2542                         continue;
2543                 if (size < 8)
2544                         return -ENOMEM;
2545                 if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2546                     put_user(chs_bytes, dst + 1))
2547                         return -EFAULT;
2548                 dst += 2;
2549                 size -= 8;
2550                 count += 8;
2551                 if (size < chs_bytes)
2552                         return -ENOMEM;
2553                 size -= chs_bytes;
2554                 count += chs_bytes;
2555                 for (c = 0; c < map->channels; c++) {
2556                         if (put_user(map->map[c], dst))
2557                                 return -EFAULT;
2558                         dst++;
2559                 }
2560         }
2561         if (put_user(count, tlv + 1))
2562                 return -EFAULT;
2563         return 0;
2564 }
2565
2566 static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2567 {
2568         struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2569         info->pcm->streams[info->stream].chmap_kctl = NULL;
2570         kfree(info);
2571 }
2572
2573 /**
2574  * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2575  * @pcm: the assigned PCM instance
2576  * @stream: stream direction
2577  * @chmap: channel map elements (for query)
2578  * @max_channels: the max number of channels for the stream
2579  * @private_value: the value passed to each kcontrol's private_value field
2580  * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2581  *
2582  * Create channel-mapping control elements assigned to the given PCM stream(s).
2583  * Return: Zero if successful, or a negative error value.
2584  */
2585 int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2586                            const struct snd_pcm_chmap_elem *chmap,
2587                            int max_channels,
2588                            unsigned long private_value,
2589                            struct snd_pcm_chmap **info_ret)
2590 {
2591         struct snd_pcm_chmap *info;
2592         struct snd_kcontrol_new knew = {
2593                 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
2594                 .access = SNDRV_CTL_ELEM_ACCESS_READ |
2595                         SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2596                         SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2597                 .info = pcm_chmap_ctl_info,
2598                 .get = pcm_chmap_ctl_get,
2599                 .tlv.c = pcm_chmap_ctl_tlv,
2600         };
2601         int err;
2602
2603         if (WARN_ON(pcm->streams[stream].chmap_kctl))
2604                 return -EBUSY;
2605         info = kzalloc(sizeof(*info), GFP_KERNEL);
2606         if (!info)
2607                 return -ENOMEM;
2608         info->pcm = pcm;
2609         info->stream = stream;
2610         info->chmap = chmap;
2611         info->max_channels = max_channels;
2612         if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2613                 knew.name = "Playback Channel Map";
2614         else
2615                 knew.name = "Capture Channel Map";
2616         knew.device = pcm->device;
2617         knew.count = pcm->streams[stream].substream_count;
2618         knew.private_value = private_value;
2619         info->kctl = snd_ctl_new1(&knew, info);
2620         if (!info->kctl) {
2621                 kfree(info);
2622                 return -ENOMEM;
2623         }
2624         info->kctl->private_free = pcm_chmap_ctl_private_free;
2625         err = snd_ctl_add(pcm->card, info->kctl);
2626         if (err < 0)
2627                 return err;
2628         pcm->streams[stream].chmap_kctl = info->kctl;
2629         if (info_ret)
2630                 *info_ret = info;
2631         return 0;
2632 }
2633 EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);