sound/core/pcm_lib.c

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