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