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 <sound/core.h>
  27 #include <sound/control.h>
  28 #include <sound/info.h>
  29 #include <sound/pcm.h>
  30 #include <sound/pcm_params.h>
  31 #include <sound/timer.h>
  32
  33 /*
  34  * fill ring buffer with silence
  35  * runtime->silence_start: starting pointer to silence area
  36  * runtime->silence_filled: size filled with silence
  37  * runtime->silence_threshold: threshold from application
  38  * runtime->silence_size: maximal size from application
  39  *
  40  * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
  41  */
  42 void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
  43 {
  44         struct snd_pcm_runtime *runtime = substream->runtime;
  45         snd_pcm_uframes_t frames, ofs, transfer;
  46
  47         if (runtime->silence_size < runtime->boundary) {
  48                 snd_pcm_sframes_t noise_dist, n;
  49                 if (runtime->silence_start != runtime->control->appl_ptr) {
  50                         n = runtime->control->appl_ptr - runtime->silence_start;
  51                         if (n < 0)
  52                                 n += runtime->boundary;
  53                         if ((snd_pcm_uframes_t)n < runtime->silence_filled)
  54                                 runtime->silence_filled -= n;
  55                         else
  56                                 runtime->silence_filled = 0;
  57                         runtime->silence_start = runtime->control->appl_ptr;
  58                 }
  59                 if (runtime->silence_filled >= runtime->buffer_size)
  60                         return;
  61                 noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
  62                 if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
  63                         return;
  64                 frames = runtime->silence_threshold - noise_dist;
  65                 if (frames > runtime->silence_size)
  66                         frames = runtime->silence_size;
  67         } else {
  68                 if (new_hw_ptr == ULONG_MAX) {  /* initialization */
  69                         snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
  70                         if (avail > runtime->buffer_size)
  71                                 avail = runtime->buffer_size;
  72                         runtime->silence_filled = avail > 0 ? avail : 0;
  73                         runtime->silence_start = (runtime->status->hw_ptr +
  74                                                   runtime->silence_filled) %
  75                                                  runtime->boundary;
  76                 } else {
  77                         ofs = runtime->status->hw_ptr;
  78                         frames = new_hw_ptr - ofs;
  79                         if ((snd_pcm_sframes_t)frames < 0)
  80                                 frames += runtime->boundary;
  81                         runtime->silence_filled -= frames;
  82                         if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
  83                                 runtime->silence_filled = 0;
  84                                 runtime->silence_start = new_hw_ptr;
  85                         } else {
  86                                 runtime->silence_start = ofs;
  87                         }
  88                 }
  89                 frames = runtime->buffer_size - runtime->silence_filled;
  90         }
  91         if (snd_BUG_ON(frames > runtime->buffer_size))
  92                 return;
  93         if (frames == 0)
  94                 return;
  95         ofs = runtime->silence_start % runtime->buffer_size;
  96         while (frames > 0) {
  97                 transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
  98                 if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
  99                     runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
 100                         if (substream->ops->silence) {
 101                                 int err;
 102                                 err = substream->ops->silence(substream, -1, ofs, transfer);
 103                                 snd_BUG_ON(err < 0);
 104                         } else {
 105                                 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
 106                                 snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
 107                         }
 108                 } else {
 109                         unsigned int c;
 110                         unsigned int channels = runtime->channels;
 111                         if (substream->ops->silence) {
 112                                 for (c = 0; c < channels; ++c) {
 113                                         int err;
 114                                         err = substream->ops->silence(substream, c, ofs, transfer);
 115                                         snd_BUG_ON(err < 0);
 116                                 }
 117                         } else {
 118                                 size_t dma_csize = runtime->dma_bytes / channels;
 119                                 for (c = 0; c < channels; ++c) {
 120                                         char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
 121                                         snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
 122                                 }
 123                         }
 124                 }
 125                 runtime->silence_filled += transfer;
 126                 frames -= transfer;
 127                 ofs = 0;
 128         }
 129 }
 130
 131 static void pcm_debug_name(struct snd_pcm_substream *substream,
 132                            char *name, size_t len)
 133 {
 134         snprintf(name, len, "pcmC%dD%d%c:%d",
 135                  substream->pcm->card->number,
 136                  substream->pcm->device,
 137                  substream->stream ? 'c' : 'p',
 138                  substream->number);
 139 }
 140
 141 #define XRUN_DEBUG_BASIC        (1<<0)
 142 #define XRUN_DEBUG_STACK        (1<<1)  /* dump also stack */
 143 #define XRUN_DEBUG_JIFFIESCHECK (1<<2)  /* do jiffies check */
 144 #define XRUN_DEBUG_PERIODUPDATE (1<<3)  /* full period update info */
 145 #define XRUN_DEBUG_HWPTRUPDATE  (1<<4)  /* full hwptr update info */
 146 #define XRUN_DEBUG_LOG          (1<<5)  /* show last 10 positions on err */
 147 #define XRUN_DEBUG_LOGONCE      (1<<6)  /* do above only once */
 148
 149 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 150
 151 #define xrun_debug(substream, mask) \
 152                         ((substream)->pstr->xrun_debug & (mask))
 153 #else
 154 #define xrun_debug(substream, mask)     0
 155 #endif
 156
 157 #define dump_stack_on_xrun(substream) do {                      \
 158                 if (xrun_debug(substream, XRUN_DEBUG_STACK))    \
 159                         dump_stack();                           \
 160         } while (0)
 161
 162 static void xrun(struct snd_pcm_substream *substream)
 163 {
 164         struct snd_pcm_runtime *runtime = substream->runtime;
 165
 166         if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
 167                 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 168         snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 169         if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
 170                 char name[16];
 171                 pcm_debug_name(substream, name, sizeof(name));
 172                 snd_printd(KERN_DEBUG "XRUN: %s\n", name);
 173                 dump_stack_on_xrun(substream);
 174         }
 175 }
 176
 177 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 178 #define hw_ptr_error(substream, fmt, args...)                           \
 179         do {                                                            \
 180                 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {          \
 181                         xrun_log_show(substream);                       \
 182                         if (printk_ratelimit()) {                       \
 183                                 snd_printd("PCM: " fmt, ##args);        \
 184                         }                                               \
 185                         dump_stack_on_xrun(substream);                  \
 186                 }                                                       \
 187         } while (0)
 188
 189 #define XRUN_LOG_CNT    10
 190
 191 struct hwptr_log_entry {
 192         unsigned long jiffies;
 193         snd_pcm_uframes_t pos;
 194         snd_pcm_uframes_t period_size;
 195         snd_pcm_uframes_t buffer_size;
 196         snd_pcm_uframes_t old_hw_ptr;
 197         snd_pcm_uframes_t hw_ptr_base;
 198 };
 199
 200 struct snd_pcm_hwptr_log {
 201         unsigned int idx;
 202         unsigned int hit: 1;
 203         struct hwptr_log_entry entries[XRUN_LOG_CNT];
 204 };
 205
 206 static void xrun_log(struct snd_pcm_substream *substream,
 207                      snd_pcm_uframes_t pos)
 208 {
 209         struct snd_pcm_runtime *runtime = substream->runtime;
 210         struct snd_pcm_hwptr_log *log = runtime->hwptr_log;
 211         struct hwptr_log_entry *entry;
 212
 213         if (log == NULL) {
 214                 log = kzalloc(sizeof(*log), GFP_ATOMIC);
 215                 if (log == NULL)
 216                         return;
 217                 runtime->hwptr_log = log;
 218         } else {
 219                 if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
 220                         return;
 221         }
 222         entry = &log->entries[log->idx];
 223         entry->jiffies = jiffies;
 224         entry->pos = pos;
 225         entry->period_size = runtime->period_size;
 226         entry->buffer_size = runtime->buffer_size;
 227         entry->old_hw_ptr = runtime->status->hw_ptr;
 228         entry->hw_ptr_base = runtime->hw_ptr_base;
 229         log->idx = (log->idx + 1) % XRUN_LOG_CNT;
 230 }
 231
 232 static void xrun_log_show(struct snd_pcm_substream *substream)
 233 {
 234         struct snd_pcm_hwptr_log *log = substream->runtime->hwptr_log;
 235         struct hwptr_log_entry *entry;
 236         char name[16];
 237         unsigned int idx;
 238         int cnt;
 239
 240         if (log == NULL)
 241                 return;
 242         if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
 243                 return;
 244         pcm_debug_name(substream, name, sizeof(name));
 245         for (cnt = 0, idx = log->idx; cnt < XRUN_LOG_CNT; cnt++) {
 246                 entry = &log->entries[idx];
 247                 if (entry->period_size == 0)
 248                         break;
 249                 snd_printd("hwptr log: %s: j=%lu, pos=%ld/%ld/%ld, "
 250                            "hwptr=%ld/%ld\n",
 251                            name, entry->jiffies, (unsigned long)entry->pos,
 252                            (unsigned long)entry->period_size,
 253                            (unsigned long)entry->buffer_size,
 254                            (unsigned long)entry->old_hw_ptr,
 255                            (unsigned long)entry->hw_ptr_base);
 256                 idx++;
 257                 idx %= XRUN_LOG_CNT;
 258         }
 259         log->hit = 1;
 260 }
 261
 262 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
 263
 264 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
 265 #define xrun_log(substream, pos)        do { } while (0)
 266 #define xrun_log_show(substream)        do { } while (0)
 267
 268 #endif
 269
 270 int snd_pcm_update_state(struct snd_pcm_substream *substream,
 271                          struct snd_pcm_runtime *runtime)
 272 {
 273         snd_pcm_uframes_t avail;
 274
 275         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 276                 avail = snd_pcm_playback_avail(runtime);
 277         else
 278                 avail = snd_pcm_capture_avail(runtime);
 279         if (avail > runtime->avail_max)
 280                 runtime->avail_max = avail;
 281         if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
 282                 if (avail >= runtime->buffer_size) {
 283                         snd_pcm_drain_done(substream);
 284                         return -EPIPE;
 285                 }
 286         } else {
 287                 if (avail >= runtime->stop_threshold) {
 288                         xrun(substream);
 289                         return -EPIPE;
 290                 }
 291         }
 292         if (runtime->twake) {
 293                 if (avail >= runtime->twake)
 294                         wake_up(&runtime->tsleep);
 295         } else if (avail >= runtime->control->avail_min)
 296                 wake_up(&runtime->sleep);
 297         return 0;
 298 }
 299
 300 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
 301                                   unsigned int in_interrupt)
 302 {
 303         struct snd_pcm_runtime *runtime = substream->runtime;
 304         snd_pcm_uframes_t pos;
 305         snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
 306         snd_pcm_sframes_t hdelta, delta;
 307         unsigned long jdelta;
 308
 309         old_hw_ptr = runtime->status->hw_ptr;
 310         pos = substream->ops->pointer(substream);
 311         if (pos == SNDRV_PCM_POS_XRUN) {
 312                 xrun(substream);
 313                 return -EPIPE;
 314         }
 315         if (pos >= runtime->buffer_size) {
 316                 if (printk_ratelimit()) {
 317                         char name[16];
 318                         pcm_debug_name(substream, name, sizeof(name));
 319                         xrun_log_show(substream);
 320                         snd_printd(KERN_ERR  "BUG: %s, pos = %ld, "
 321                                    "buffer size = %ld, period size = %ld\n",
 322                                    name, pos, runtime->buffer_size,
 323                                    runtime->period_size);
 324                 }
 325                 pos = 0;
 326         }
 327         pos -= pos % runtime->min_align;
 328         if (xrun_debug(substream, XRUN_DEBUG_LOG))
 329                 xrun_log(substream, pos);
 330         hw_base = runtime->hw_ptr_base;
 331         new_hw_ptr = hw_base + pos;
 332         if (in_interrupt) {
 333                 /* we know that one period was processed */
 334                 /* delta = "expected next hw_ptr" for in_interrupt != 0 */
 335                 delta = runtime->hw_ptr_interrupt + runtime->period_size;
 336                 if (delta > new_hw_ptr) {
 337                         /* check for double acknowledged interrupts */
 338                         hdelta = jiffies - runtime->hw_ptr_jiffies;
 339                         if (hdelta > runtime->hw_ptr_buffer_jiffies/2) {
 340                                 hw_base += runtime->buffer_size;
 341                                 if (hw_base >= runtime->boundary)
 342                                         hw_base = 0;
 343                                 new_hw_ptr = hw_base + pos;
 344                                 goto __delta;
 345                         }
 346                 }
 347         }
 348         /* new_hw_ptr might be lower than old_hw_ptr in case when */
 349         /* pointer crosses the end of the ring buffer */
 350         if (new_hw_ptr < old_hw_ptr) {
 351                 hw_base += runtime->buffer_size;
 352                 if (hw_base >= runtime->boundary)
 353                         hw_base = 0;
 354                 new_hw_ptr = hw_base + pos;
 355         }
 356       __delta:
 357         delta = new_hw_ptr - old_hw_ptr;
 358         if (delta < 0)
 359                 delta += runtime->boundary;
 360         if (xrun_debug(substream, in_interrupt ?
 361                         XRUN_DEBUG_PERIODUPDATE : XRUN_DEBUG_HWPTRUPDATE)) {
 362                 char name[16];
 363                 pcm_debug_name(substream, name, sizeof(name));
 364                 snd_printd("%s_update: %s: pos=%u/%u/%u, "
 365                            "hwptr=%ld/%ld/%ld/%ld\n",
 366                            in_interrupt ? "period" : "hwptr",
 367                            name,
 368                            (unsigned int)pos,
 369                            (unsigned int)runtime->period_size,
 370                            (unsigned int)runtime->buffer_size,
 371                            (unsigned long)delta,
 372                            (unsigned long)old_hw_ptr,
 373                            (unsigned long)new_hw_ptr,
 374                            (unsigned long)runtime->hw_ptr_base);
 375         }
 376
 377         if (runtime->no_period_wakeup) {
 378                 /*
 379                  * Without regular period interrupts, we have to check
 380                  * the elapsed time to detect xruns.
 381                  */
 382                 jdelta = jiffies - runtime->hw_ptr_jiffies;
 383                 if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
 384                         goto no_delta_check;
 385                 hdelta = jdelta - delta * HZ / runtime->rate;
 386                 while (hdelta > runtime->hw_ptr_buffer_jiffies / 2 + 1) {
 387                         delta += runtime->buffer_size;
 388                         hw_base += runtime->buffer_size;
 389                         if (hw_base >= runtime->boundary)
 390                                 hw_base = 0;
 391                         new_hw_ptr = hw_base + pos;
 392                         hdelta -= runtime->hw_ptr_buffer_jiffies;
 393                 }
 394                 goto no_delta_check;
 395         }
 396
 397         /* something must be really wrong */
 398         if (delta >= runtime->buffer_size + runtime->period_size) {
 399                 hw_ptr_error(substream,
 400                                "Unexpected hw_pointer value %s"
 401                                "(stream=%i, pos=%ld, new_hw_ptr=%ld, "
 402                                "old_hw_ptr=%ld)\n",
 403                                      in_interrupt ? "[Q] " : "[P]",
 404                                      substream->stream, (long)pos,
 405                                      (long)new_hw_ptr, (long)old_hw_ptr);
 406                 return 0;
 407         }
 408
 409         /* Do jiffies check only in xrun_debug mode */
 410         if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
 411                 goto no_jiffies_check;
 412
 413         /* Skip the jiffies check for hardwares with BATCH flag.
 414          * Such hardware usually just increases the position at each IRQ,
 415          * thus it can't give any strange position.
 416          */
 417         if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
 418                 goto no_jiffies_check;
 419         hdelta = delta;
 420         if (hdelta < runtime->delay)
 421                 goto no_jiffies_check;
 422         hdelta -= runtime->delay;
 423         jdelta = jiffies - runtime->hw_ptr_jiffies;
 424         if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
 425                 delta = jdelta /
 426                         (((runtime->period_size * HZ) / runtime->rate)
 427                                                                 + HZ/100);
 428                 /* move new_hw_ptr according jiffies not pos variable */
 429                 new_hw_ptr = old_hw_ptr;
 430                 hw_base = delta;
 431                 /* use loop to avoid checks for delta overflows */
 432                 /* the delta value is small or zero in most cases */
 433                 while (delta > 0) {
 434                         new_hw_ptr += runtime->period_size;
 435                         if (new_hw_ptr >= runtime->boundary)
 436                                 new_hw_ptr -= runtime->boundary;
 437                         delta--;
 438                 }
 439                 /* align hw_base to buffer_size */
 440                 hw_ptr_error(substream,
 441                              "hw_ptr skipping! %s"
 442                              "(pos=%ld, delta=%ld, period=%ld, "
 443                              "jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
 444                              in_interrupt ? "[Q] " : "",
 445                              (long)pos, (long)hdelta,
 446                              (long)runtime->period_size, jdelta,
 447                              ((hdelta * HZ) / runtime->rate), hw_base,
 448                              (unsigned long)old_hw_ptr,
 449                              (unsigned long)new_hw_ptr);
 450                 /* reset values to proper state */
 451                 delta = 0;
 452                 hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
 453         }
 454  no_jiffies_check:
 455         if (delta > runtime->period_size + runtime->period_size / 2) {
 456                 hw_ptr_error(substream,
 457                              "Lost interrupts? %s"
 458                              "(stream=%i, delta=%ld, new_hw_ptr=%ld, "
 459                              "old_hw_ptr=%ld)\n",
 460                              in_interrupt ? "[Q] " : "",
 461                              substream->stream, (long)delta,
 462                              (long)new_hw_ptr,
 463                              (long)old_hw_ptr);
 464         }
 465
 466  no_delta_check:
 467         if (runtime->status->hw_ptr == new_hw_ptr)
 468                 return 0;
 469
 470         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 471             runtime->silence_size > 0)
 472                 snd_pcm_playback_silence(substream, new_hw_ptr);
 473
 474         if (in_interrupt) {
 475                 delta = new_hw_ptr - runtime->hw_ptr_interrupt;
 476                 if (delta < 0)
 477                         delta += runtime->boundary;
 478                 delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
 479                 runtime->hw_ptr_interrupt += delta;
 480                 if (runtime->hw_ptr_interrupt >= runtime->boundary)
 481                         runtime->hw_ptr_interrupt -= runtime->boundary;
 482         }
 483         runtime->hw_ptr_base = hw_base;
 484         runtime->status->hw_ptr = new_hw_ptr;
 485         runtime->hw_ptr_jiffies = jiffies;
 486         if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
 487                 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 488
 489         return snd_pcm_update_state(substream, runtime);
 490 }
 491
 492 /* CAUTION: call it with irq disabled */
 493 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
 494 {
 495         return snd_pcm_update_hw_ptr0(substream, 0);
 496 }
 497
 498 /**
 499  * snd_pcm_set_ops - set the PCM operators
 500  * @pcm: the pcm instance
 501  * @direction: stream direction, SNDRV_PCM_STREAM_XXX
 502  * @ops: the operator table
 503  *
 504  * Sets the given PCM operators to the pcm instance.
 505  */
 506 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction, struct snd_pcm_ops *ops)
 507 {
 508         struct snd_pcm_str *stream = &pcm->streams[direction];
 509         struct snd_pcm_substream *substream;
 510
 511         for (substream = stream->substream; substream != NULL; substream = substream->next)
 512                 substream->ops = ops;
 513 }
 514
 515 EXPORT_SYMBOL(snd_pcm_set_ops);
 516
 517 /**
 518  * snd_pcm_sync - set the PCM sync id
 519  * @substream: the pcm substream
 520  *
 521  * Sets the PCM sync identifier for the card.
 522  */
 523 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
 524 {
 525         struct snd_pcm_runtime *runtime = substream->runtime;
 526
 527         runtime->sync.id32[0] = substream->pcm->card->number;
 528         runtime->sync.id32[1] = -1;
 529         runtime->sync.id32[2] = -1;
 530         runtime->sync.id32[3] = -1;
 531 }
 532
 533 EXPORT_SYMBOL(snd_pcm_set_sync);
 534
 535 /*
 536  *  Standard ioctl routine
 537  */
 538
 539 static inline unsigned int div32(unsigned int a, unsigned int b,
 540                                  unsigned int *r)
 541 {
 542         if (b == 0) {
 543                 *r = 0;
 544                 return UINT_MAX;
 545         }
 546         *r = a % b;
 547         return a / b;
 548 }
 549
 550 static inline unsigned int div_down(unsigned int a, unsigned int b)
 551 {
 552         if (b == 0)
 553                 return UINT_MAX;
 554         return a / b;
 555 }
 556
 557 static inline unsigned int div_up(unsigned int a, unsigned int b)
 558 {
 559         unsigned int r;
 560         unsigned int q;
 561         if (b == 0)
 562                 return UINT_MAX;
 563         q = div32(a, b, &r);
 564         if (r)
 565                 ++q;
 566         return q;
 567 }
 568
 569 static inline unsigned int mul(unsigned int a, unsigned int b)
 570 {
 571         if (a == 0)
 572                 return 0;
 573         if (div_down(UINT_MAX, a) < b)
 574                 return UINT_MAX;
 575         return a * b;
 576 }
 577
 578 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
 579                                     unsigned int c, unsigned int *r)
 580 {
 581         u_int64_t n = (u_int64_t) a * b;
 582         if (c == 0) {
 583                 snd_BUG_ON(!n);
 584                 *r = 0;
 585                 return UINT_MAX;
 586         }
 587         n = div_u64_rem(n, c, r);
 588         if (n >= UINT_MAX) {
 589                 *r = 0;
 590                 return UINT_MAX;
 591         }
 592         return n;
 593 }
 594
 595 /**
 596  * snd_interval_refine - refine the interval value of configurator
 597  * @i: the interval value to refine
 598  * @v: the interval value to refer to
 599  *
 600  * Refines the interval value with the reference value.
 601  * The interval is changed to the range satisfying both intervals.
 602  * The interval status (min, max, integer, etc.) are evaluated.
 603  *
 604  * Returns non-zero if the value is changed, zero if not changed.
 605  */
 606 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
 607 {
 608         int changed = 0;
 609         if (snd_BUG_ON(snd_interval_empty(i)))
 610                 return -EINVAL;
 611         if (i->min < v->min) {
 612                 i->min = v->min;
 613                 i->openmin = v->openmin;
 614                 changed = 1;
 615         } else if (i->min == v->min && !i->openmin && v->openmin) {
 616                 i->openmin = 1;
 617                 changed = 1;
 618         }
 619         if (i->max > v->max) {
 620                 i->max = v->max;
 621                 i->openmax = v->openmax;
 622                 changed = 1;
 623         } else if (i->max == v->max && !i->openmax && v->openmax) {
 624                 i->openmax = 1;
 625                 changed = 1;
 626         }
 627         if (!i->integer && v->integer) {
 628                 i->integer = 1;
 629                 changed = 1;
 630         }
 631         if (i->integer) {
 632                 if (i->openmin) {
 633                         i->min++;
 634                         i->openmin = 0;
 635                 }
 636                 if (i->openmax) {
 637                         i->max--;
 638                         i->openmax = 0;
 639                 }
 640         } else if (!i->openmin && !i->openmax && i->min == i->max)
 641                 i->integer = 1;
 642         if (snd_interval_checkempty(i)) {
 643                 snd_interval_none(i);
 644                 return -EINVAL;
 645         }
 646         return changed;
 647 }
 648
 649 EXPORT_SYMBOL(snd_interval_refine);
 650
 651 static int snd_interval_refine_first(struct snd_interval *i)
 652 {
 653         if (snd_BUG_ON(snd_interval_empty(i)))
 654                 return -EINVAL;
 655         if (snd_interval_single(i))
 656                 return 0;
 657         i->max = i->min;
 658         i->openmax = i->openmin;
 659         if (i->openmax)
 660                 i->max++;
 661         return 1;
 662 }
 663
 664 static int snd_interval_refine_last(struct snd_interval *i)
 665 {
 666         if (snd_BUG_ON(snd_interval_empty(i)))
 667                 return -EINVAL;
 668         if (snd_interval_single(i))
 669                 return 0;
 670         i->min = i->max;
 671         i->openmin = i->openmax;
 672         if (i->openmin)
 673                 i->min--;
 674         return 1;
 675 }
 676
 677 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 678 {
 679         if (a->empty || b->empty) {
 680                 snd_interval_none(c);
 681                 return;
 682         }
 683         c->empty = 0;
 684         c->min = mul(a->min, b->min);
 685         c->openmin = (a->openmin || b->openmin);
 686         c->max = mul(a->max,  b->max);
 687         c->openmax = (a->openmax || b->openmax);
 688         c->integer = (a->integer && b->integer);
 689 }
 690
 691 /**
 692  * snd_interval_div - refine the interval value with division
 693  * @a: dividend
 694  * @b: divisor
 695  * @c: quotient
 696  *
 697  * c = a / b
 698  *
 699  * Returns non-zero if the value is changed, zero if not changed.
 700  */
 701 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 702 {
 703         unsigned int r;
 704         if (a->empty || b->empty) {
 705                 snd_interval_none(c);
 706                 return;
 707         }
 708         c->empty = 0;
 709         c->min = div32(a->min, b->max, &r);
 710         c->openmin = (r || a->openmin || b->openmax);
 711         if (b->min > 0) {
 712                 c->max = div32(a->max, b->min, &r);
 713                 if (r) {
 714                         c->max++;
 715                         c->openmax = 1;
 716                 } else
 717                         c->openmax = (a->openmax || b->openmin);
 718         } else {
 719                 c->max = UINT_MAX;
 720                 c->openmax = 0;
 721         }
 722         c->integer = 0;
 723 }
 724
 725 /**
 726  * snd_interval_muldivk - refine the interval value
 727  * @a: dividend 1
 728  * @b: dividend 2
 729  * @k: divisor (as integer)
 730  * @c: result
 731   *
 732  * c = a * b / k
 733  *
 734  * Returns non-zero if the value is changed, zero if not changed.
 735  */
 736 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
 737                       unsigned int k, struct snd_interval *c)
 738 {
 739         unsigned int r;
 740         if (a->empty || b->empty) {
 741                 snd_interval_none(c);
 742                 return;
 743         }
 744         c->empty = 0;
 745         c->min = muldiv32(a->min, b->min, k, &r);
 746         c->openmin = (r || a->openmin || b->openmin);
 747         c->max = muldiv32(a->max, b->max, k, &r);
 748         if (r) {
 749                 c->max++;
 750                 c->openmax = 1;
 751         } else
 752                 c->openmax = (a->openmax || b->openmax);
 753         c->integer = 0;
 754 }
 755
 756 /**
 757  * snd_interval_mulkdiv - refine the interval value
 758  * @a: dividend 1
 759  * @k: dividend 2 (as integer)
 760  * @b: divisor
 761  * @c: result
 762  *
 763  * c = a * k / b
 764  *
 765  * Returns non-zero if the value is changed, zero if not changed.
 766  */
 767 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
 768                       const struct snd_interval *b, struct snd_interval *c)
 769 {
 770         unsigned int r;
 771         if (a->empty || b->empty) {
 772                 snd_interval_none(c);
 773                 return;
 774         }
 775         c->empty = 0;
 776         c->min = muldiv32(a->min, k, b->max, &r);
 777         c->openmin = (r || a->openmin || b->openmax);
 778         if (b->min > 0) {
 779                 c->max = muldiv32(a->max, k, b->min, &r);
 780                 if (r) {
 781                         c->max++;
 782                         c->openmax = 1;
 783                 } else
 784                         c->openmax = (a->openmax || b->openmin);
 785         } else {
 786                 c->max = UINT_MAX;
 787                 c->openmax = 0;
 788         }
 789         c->integer = 0;
 790 }
 791
 792 /* ---- */
 793
 794
 795 /**
 796  * snd_interval_ratnum - refine the interval value
 797  * @i: interval to refine
 798  * @rats_count: number of ratnum_t
 799  * @rats: ratnum_t array
 800  * @nump: pointer to store the resultant numerator
 801  * @denp: pointer to store the resultant denominator
 802  *
 803  * Returns non-zero if the value is changed, zero if not changed.
 804  */
 805 int snd_interval_ratnum(struct snd_interval *i,
 806                         unsigned int rats_count, struct snd_ratnum *rats,
 807                         unsigned int *nump, unsigned int *denp)
 808 {
 809         unsigned int best_num, best_den;
 810         int best_diff;
 811         unsigned int k;
 812         struct snd_interval t;
 813         int err;
 814         unsigned int result_num, result_den;
 815         int result_diff;
 816
 817         best_num = best_den = best_diff = 0;
 818         for (k = 0; k < rats_count; ++k) {
 819                 unsigned int num = rats[k].num;
 820                 unsigned int den;
 821                 unsigned int q = i->min;
 822                 int diff;
 823                 if (q == 0)
 824                         q = 1;
 825                 den = div_up(num, q);
 826                 if (den < rats[k].den_min)
 827                         continue;
 828                 if (den > rats[k].den_max)
 829                         den = rats[k].den_max;
 830                 else {
 831                         unsigned int r;
 832                         r = (den - rats[k].den_min) % rats[k].den_step;
 833                         if (r != 0)
 834                                 den -= r;
 835                 }
 836                 diff = num - q * den;
 837                 if (diff < 0)
 838                         diff = -diff;
 839                 if (best_num == 0 ||
 840                     diff * best_den < best_diff * den) {
 841                         best_diff = diff;
 842                         best_den = den;
 843                         best_num = num;
 844                 }
 845         }
 846         if (best_den == 0) {
 847                 i->empty = 1;
 848                 return -EINVAL;
 849         }
 850         t.min = div_down(best_num, best_den);
 851         t.openmin = !!(best_num % best_den);
 852
 853         result_num = best_num;
 854         result_diff = best_diff;
 855         result_den = best_den;
 856         best_num = best_den = best_diff = 0;
 857         for (k = 0; k < rats_count; ++k) {
 858                 unsigned int num = rats[k].num;
 859                 unsigned int den;
 860                 unsigned int q = i->max;
 861                 int diff;
 862                 if (q == 0) {
 863                         i->empty = 1;
 864                         return -EINVAL;
 865                 }
 866                 den = div_down(num, q);
 867                 if (den > rats[k].den_max)
 868                         continue;
 869                 if (den < rats[k].den_min)
 870                         den = rats[k].den_min;
 871                 else {
 872                         unsigned int r;
 873                         r = (den - rats[k].den_min) % rats[k].den_step;
 874                         if (r != 0)
 875                                 den += rats[k].den_step - r;
 876                 }
 877                 diff = q * den - num;
 878                 if (diff < 0)
 879                         diff = -diff;
 880                 if (best_num == 0 ||
 881                     diff * best_den < best_diff * den) {
 882                         best_diff = diff;
 883                         best_den = den;
 884                         best_num = num;
 885                 }
 886         }
 887         if (best_den == 0) {
 888                 i->empty = 1;
 889                 return -EINVAL;
 890         }
 891         t.max = div_up(best_num, best_den);
 892         t.openmax = !!(best_num % best_den);
 893         t.integer = 0;
 894         err = snd_interval_refine(i, &t);
 895         if (err < 0)
 896                 return err;
 897
 898         if (snd_interval_single(i)) {
 899                 if (best_diff * result_den < result_diff * best_den) {
 900                         result_num = best_num;
 901                         result_den = best_den;
 902                 }
 903                 if (nump)
 904                         *nump = result_num;
 905                 if (denp)
 906                         *denp = result_den;
 907         }
 908         return err;
 909 }
 910
 911 EXPORT_SYMBOL(snd_interval_ratnum);
 912
 913 /**
 914  * snd_interval_ratden - refine the interval value
 915  * @i: interval to refine
 916  * @rats_count: number of struct ratden
 917  * @rats: struct ratden array
 918  * @nump: pointer to store the resultant numerator
 919  * @denp: pointer to store the resultant denominator
 920  *
 921  * Returns non-zero if the value is changed, zero if not changed.
 922  */
 923 static int snd_interval_ratden(struct snd_interval *i,
 924                                unsigned int rats_count, struct snd_ratden *rats,
 925                                unsigned int *nump, unsigned int *denp)
 926 {
 927         unsigned int best_num, best_diff, best_den;
 928         unsigned int k;
 929         struct snd_interval t;
 930         int err;
 931
 932         best_num = best_den = best_diff = 0;
 933         for (k = 0; k < rats_count; ++k) {
 934                 unsigned int num;
 935                 unsigned int den = rats[k].den;
 936                 unsigned int q = i->min;
 937                 int diff;
 938                 num = mul(q, den);
 939                 if (num > rats[k].num_max)
 940                         continue;
 941                 if (num < rats[k].num_min)
 942                         num = rats[k].num_max;
 943                 else {
 944                         unsigned int r;
 945                         r = (num - rats[k].num_min) % rats[k].num_step;
 946                         if (r != 0)
 947                                 num += rats[k].num_step - r;
 948                 }
 949                 diff = num - q * den;
 950                 if (best_num == 0 ||
 951                     diff * best_den < best_diff * den) {
 952                         best_diff = diff;
 953                         best_den = den;
 954                         best_num = num;
 955                 }
 956         }
 957         if (best_den == 0) {
 958                 i->empty = 1;
 959                 return -EINVAL;
 960         }
 961         t.min = div_down(best_num, best_den);
 962         t.openmin = !!(best_num % best_den);
 963
 964         best_num = best_den = best_diff = 0;
 965         for (k = 0; k < rats_count; ++k) {
 966                 unsigned int num;
 967                 unsigned int den = rats[k].den;
 968                 unsigned int q = i->max;
 969                 int diff;
 970                 num = mul(q, den);
 971                 if (num < rats[k].num_min)
 972                         continue;
 973                 if (num > rats[k].num_max)
 974                         num = rats[k].num_max;
 975                 else {
 976                         unsigned int r;
 977                         r = (num - rats[k].num_min) % rats[k].num_step;
 978                         if (r != 0)
 979                                 num -= r;
 980                 }
 981                 diff = q * den - num;
 982                 if (best_num == 0 ||
 983                     diff * best_den < best_diff * den) {
 984                         best_diff = diff;
 985                         best_den = den;
 986                         best_num = num;
 987                 }
 988         }
 989         if (best_den == 0) {
 990                 i->empty = 1;
 991                 return -EINVAL;
 992         }
 993         t.max = div_up(best_num, best_den);
 994         t.openmax = !!(best_num % best_den);
 995         t.integer = 0;
 996         err = snd_interval_refine(i, &t);
 997         if (err < 0)
 998                 return err;
 999
1000         if (snd_interval_single(i)) {
1001                 if (nump)
1002                         *nump = best_num;
1003                 if (denp)
1004                         *denp = best_den;
1005         }
1006         return err;
1007 }
1008
1009 /**
1010  * snd_interval_list - refine the interval value from the list
1011  * @i: the interval value to refine
1012  * @count: the number of elements in the list
1013  * @list: the value list
1014  * @mask: the bit-mask to evaluate
1015  *
1016  * Refines the interval value from the list.
1017  * When mask is non-zero, only the elements corresponding to bit 1 are
1018  * evaluated.
1019  *
1020  * Returns non-zero if the value is changed, zero if not changed.
1021  */
1022 int snd_interval_list(struct snd_interval *i, unsigned int count, unsigned int *list, unsigned int mask)
1023 {
1024         unsigned int k;
1025         struct snd_interval list_range;
1026
1027         if (!count) {
1028                 i->empty = 1;
1029                 return -EINVAL;
1030         }
1031         snd_interval_any(&list_range);
1032         list_range.min = UINT_MAX;
1033         list_range.max = 0;
1034         for (k = 0; k < count; k++) {
1035                 if (mask && !(mask & (1 << k)))
1036                         continue;
1037                 if (!snd_interval_test(i, list[k]))
1038                         continue;
1039                 list_range.min = min(list_range.min, list[k]);
1040                 list_range.max = max(list_range.max, list[k]);
1041         }
1042         return snd_interval_refine(i, &list_range);
1043 }
1044
1045 EXPORT_SYMBOL(snd_interval_list);
1046
1047 static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
1048 {
1049         unsigned int n;
1050         int changed = 0;
1051         n = (i->min - min) % step;
1052         if (n != 0 || i->openmin) {
1053                 i->min += step - n;
1054                 changed = 1;
1055         }
1056         n = (i->max - min) % step;
1057         if (n != 0 || i->openmax) {
1058                 i->max -= n;
1059                 changed = 1;
1060         }
1061         if (snd_interval_checkempty(i)) {
1062                 i->empty = 1;
1063                 return -EINVAL;
1064         }
1065         return changed;
1066 }
1067
1068 /* Info constraints helpers */
1069
1070 /**
1071  * snd_pcm_hw_rule_add - add the hw-constraint rule
1072  * @runtime: the pcm runtime instance
1073  * @cond: condition bits
1074  * @var: the variable to evaluate
1075  * @func: the evaluation function
1076  * @private: the private data pointer passed to function
1077  * @dep: the dependent variables
1078  *
1079  * Returns zero if successful, or a negative error code on failure.
1080  */
1081 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1082                         int var,
1083                         snd_pcm_hw_rule_func_t func, void *private,
1084                         int dep, ...)
1085 {
1086         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1087         struct snd_pcm_hw_rule *c;
1088         unsigned int k;
1089         va_list args;
1090         va_start(args, dep);
1091         if (constrs->rules_num >= constrs->rules_all) {
1092                 struct snd_pcm_hw_rule *new;
1093                 unsigned int new_rules = constrs->rules_all + 16;
1094                 new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1095                 if (!new)
1096                         return -ENOMEM;
1097                 if (constrs->rules) {
1098                         memcpy(new, constrs->rules,
1099                                constrs->rules_num * sizeof(*c));
1100                         kfree(constrs->rules);
1101                 }
1102                 constrs->rules = new;
1103                 constrs->rules_all = new_rules;
1104         }
1105         c = &constrs->rules[constrs->rules_num];
1106         c->cond = cond;
1107         c->func = func;
1108         c->var = var;
1109         c->private = private;
1110         k = 0;
1111         while (1) {
1112                 if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps)))
1113                         return -EINVAL;
1114                 c->deps[k++] = dep;
1115                 if (dep < 0)
1116                         break;
1117                 dep = va_arg(args, int);
1118         }
1119         constrs->rules_num++;
1120         va_end(args);
1121         return 0;
1122 }
1123
1124 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1125
1126 /**
1127  * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1128  * @runtime: PCM runtime instance
1129  * @var: hw_params variable to apply the mask
1130  * @mask: the bitmap mask
1131  *
1132  * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1133  */
1134 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1135                                u_int32_t mask)
1136 {
1137         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1138         struct snd_mask *maskp = constrs_mask(constrs, var);
1139         *maskp->bits &= mask;
1140         memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1141         if (*maskp->bits == 0)
1142                 return -EINVAL;
1143         return 0;
1144 }
1145
1146 /**
1147  * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1148  * @runtime: PCM runtime instance
1149  * @var: hw_params variable to apply the mask
1150  * @mask: the 64bit bitmap mask
1151  *
1152  * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1153  */
1154 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1155                                  u_int64_t mask)
1156 {
1157         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1158         struct snd_mask *maskp = constrs_mask(constrs, var);
1159         maskp->bits[0] &= (u_int32_t)mask;
1160         maskp->bits[1] &= (u_int32_t)(mask >> 32);
1161         memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1162         if (! maskp->bits[0] && ! maskp->bits[1])
1163                 return -EINVAL;
1164         return 0;
1165 }
1166
1167 /**
1168  * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1169  * @runtime: PCM runtime instance
1170  * @var: hw_params variable to apply the integer constraint
1171  *
1172  * Apply the constraint of integer to an interval parameter.
1173  */
1174 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1175 {
1176         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1177         return snd_interval_setinteger(constrs_interval(constrs, var));
1178 }
1179
1180 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1181
1182 /**
1183  * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1184  * @runtime: PCM runtime instance
1185  * @var: hw_params variable to apply the range
1186  * @min: the minimal value
1187  * @max: the maximal value
1188  *
1189  * Apply the min/max range constraint to an interval parameter.
1190  */
1191 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1192                                  unsigned int min, unsigned int max)
1193 {
1194         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1195         struct snd_interval t;
1196         t.min = min;
1197         t.max = max;
1198         t.openmin = t.openmax = 0;
1199         t.integer = 0;
1200         return snd_interval_refine(constrs_interval(constrs, var), &t);
1201 }
1202
1203 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1204
1205 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1206                                 struct snd_pcm_hw_rule *rule)
1207 {
1208         struct snd_pcm_hw_constraint_list *list = rule->private;
1209         return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1210 }
1211
1212
1213 /**
1214  * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1215  * @runtime: PCM runtime instance
1216  * @cond: condition bits
1217  * @var: hw_params variable to apply the list constraint
1218  * @l: list
1219  *
1220  * Apply the list of constraints to an interval parameter.
1221  */
1222 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1223                                unsigned int cond,
1224                                snd_pcm_hw_param_t var,
1225                                struct snd_pcm_hw_constraint_list *l)
1226 {
1227         return snd_pcm_hw_rule_add(runtime, cond, var,
1228                                    snd_pcm_hw_rule_list, l,
1229                                    var, -1);
1230 }
1231
1232 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1233
1234 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1235                                    struct snd_pcm_hw_rule *rule)
1236 {
1237         struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1238         unsigned int num = 0, den = 0;
1239         int err;
1240         err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1241                                   r->nrats, r->rats, &num, &den);
1242         if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1243                 params->rate_num = num;
1244                 params->rate_den = den;
1245         }
1246         return err;
1247 }
1248
1249 /**
1250  * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1251  * @runtime: PCM runtime instance
1252  * @cond: condition bits
1253  * @var: hw_params variable to apply the ratnums constraint
1254  * @r: struct snd_ratnums constriants
1255  */
1256 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1257                                   unsigned int cond,
1258                                   snd_pcm_hw_param_t var,
1259                                   struct snd_pcm_hw_constraint_ratnums *r)
1260 {
1261         return snd_pcm_hw_rule_add(runtime, cond, var,
1262                                    snd_pcm_hw_rule_ratnums, r,
1263                                    var, -1);
1264 }
1265
1266 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1267
1268 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1269                                    struct snd_pcm_hw_rule *rule)
1270 {
1271         struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1272         unsigned int num = 0, den = 0;
1273         int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1274                                   r->nrats, r->rats, &num, &den);
1275         if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1276                 params->rate_num = num;
1277                 params->rate_den = den;
1278         }
1279         return err;
1280 }
1281
1282 /**
1283  * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1284  * @runtime: PCM runtime instance
1285  * @cond: condition bits
1286  * @var: hw_params variable to apply the ratdens constraint
1287  * @r: struct snd_ratdens constriants
1288  */
1289 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1290                                   unsigned int cond,
1291                                   snd_pcm_hw_param_t var,
1292                                   struct snd_pcm_hw_constraint_ratdens *r)
1293 {
1294         return snd_pcm_hw_rule_add(runtime, cond, var,
1295                                    snd_pcm_hw_rule_ratdens, r,
1296                                    var, -1);
1297 }
1298
1299 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1300
1301 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1302                                   struct snd_pcm_hw_rule *rule)
1303 {
1304         unsigned int l = (unsigned long) rule->private;
1305         int width = l & 0xffff;
1306         unsigned int msbits = l >> 16;
1307         struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1308         if (snd_interval_single(i) && snd_interval_value(i) == width)
1309                 params->msbits = msbits;
1310         return 0;
1311 }
1312
1313 /**
1314  * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1315  * @runtime: PCM runtime instance
1316  * @cond: condition bits
1317  * @width: sample bits width
1318  * @msbits: msbits width
1319  */
1320 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1321                                  unsigned int cond,
1322                                  unsigned int width,
1323                                  unsigned int msbits)
1324 {
1325         unsigned long l = (msbits << 16) | width;
1326         return snd_pcm_hw_rule_add(runtime, cond, -1,
1327                                     snd_pcm_hw_rule_msbits,
1328                                     (void*) l,
1329                                     SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1330 }
1331
1332 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1333
1334 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1335                                 struct snd_pcm_hw_rule *rule)
1336 {
1337         unsigned long step = (unsigned long) rule->private;
1338         return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1339 }
1340
1341 /**
1342  * snd_pcm_hw_constraint_step - add a hw constraint step rule
1343  * @runtime: PCM runtime instance
1344  * @cond: condition bits
1345  * @var: hw_params variable to apply the step constraint
1346  * @step: step size
1347  */
1348 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1349                                unsigned int cond,
1350                                snd_pcm_hw_param_t var,
1351                                unsigned long step)
1352 {
1353         return snd_pcm_hw_rule_add(runtime, cond, var,
1354                                    snd_pcm_hw_rule_step, (void *) step,
1355                                    var, -1);
1356 }
1357
1358 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1359
1360 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1361 {
1362         static unsigned int pow2_sizes[] = {
1363                 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1364                 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1365                 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1366                 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1367         };
1368         return snd_interval_list(hw_param_interval(params, rule->var),
1369                                  ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1370 }
1371
1372 /**
1373  * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1374  * @runtime: PCM runtime instance
1375  * @cond: condition bits
1376  * @var: hw_params variable to apply the power-of-2 constraint
1377  */
1378 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1379                                unsigned int cond,
1380                                snd_pcm_hw_param_t var)
1381 {
1382         return snd_pcm_hw_rule_add(runtime, cond, var,
1383                                    snd_pcm_hw_rule_pow2, NULL,
1384                                    var, -1);
1385 }
1386
1387 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1388
1389 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1390                                   snd_pcm_hw_param_t var)
1391 {
1392         if (hw_is_mask(var)) {
1393                 snd_mask_any(hw_param_mask(params, var));
1394                 params->cmask |= 1 << var;
1395                 params->rmask |= 1 << var;
1396                 return;
1397         }
1398         if (hw_is_interval(var)) {
1399                 snd_interval_any(hw_param_interval(params, var));
1400                 params->cmask |= 1 << var;
1401                 params->rmask |= 1 << var;
1402                 return;
1403         }
1404         snd_BUG();
1405 }
1406
1407 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1408 {
1409         unsigned int k;
1410         memset(params, 0, sizeof(*params));
1411         for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1412                 _snd_pcm_hw_param_any(params, k);
1413         for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1414                 _snd_pcm_hw_param_any(params, k);
1415         params->info = ~0U;
1416 }
1417
1418 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1419
1420 /**
1421  * snd_pcm_hw_param_value - return @params field @var value
1422  * @params: the hw_params instance
1423  * @var: parameter to retrieve
1424  * @dir: pointer to the direction (-1,0,1) or %NULL
1425  *
1426  * Return the value for field @var if it's fixed in configuration space
1427  * defined by @params. Return -%EINVAL otherwise.
1428  */
1429 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1430                            snd_pcm_hw_param_t var, int *dir)
1431 {
1432         if (hw_is_mask(var)) {
1433                 const struct snd_mask *mask = hw_param_mask_c(params, var);
1434                 if (!snd_mask_single(mask))
1435                         return -EINVAL;
1436                 if (dir)
1437                         *dir = 0;
1438                 return snd_mask_value(mask);
1439         }
1440         if (hw_is_interval(var)) {
1441                 const struct snd_interval *i = hw_param_interval_c(params, var);
1442                 if (!snd_interval_single(i))
1443                         return -EINVAL;
1444                 if (dir)
1445                         *dir = i->openmin;
1446                 return snd_interval_value(i);
1447         }
1448         return -EINVAL;
1449 }
1450
1451 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1452
1453 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1454                                 snd_pcm_hw_param_t var)
1455 {
1456         if (hw_is_mask(var)) {
1457                 snd_mask_none(hw_param_mask(params, var));
1458                 params->cmask |= 1 << var;
1459                 params->rmask |= 1 << var;
1460         } else if (hw_is_interval(var)) {
1461                 snd_interval_none(hw_param_interval(params, var));
1462                 params->cmask |= 1 << var;
1463                 params->rmask |= 1 << var;
1464         } else {
1465                 snd_BUG();
1466         }
1467 }
1468
1469 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1470
1471 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1472                                    snd_pcm_hw_param_t var)
1473 {
1474         int changed;
1475         if (hw_is_mask(var))
1476                 changed = snd_mask_refine_first(hw_param_mask(params, var));
1477         else if (hw_is_interval(var))
1478                 changed = snd_interval_refine_first(hw_param_interval(params, var));
1479         else
1480                 return -EINVAL;
1481         if (changed) {
1482                 params->cmask |= 1 << var;
1483                 params->rmask |= 1 << var;
1484         }
1485         return changed;
1486 }
1487
1488
1489 /**
1490  * snd_pcm_hw_param_first - refine config space and return minimum value
1491  * @pcm: PCM instance
1492  * @params: the hw_params instance
1493  * @var: parameter to retrieve
1494  * @dir: pointer to the direction (-1,0,1) or %NULL
1495  *
1496  * Inside configuration space defined by @params remove from @var all
1497  * values > minimum. Reduce configuration space accordingly.
1498  * Return the minimum.
1499  */
1500 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1501                            struct snd_pcm_hw_params *params,
1502                            snd_pcm_hw_param_t var, int *dir)
1503 {
1504         int changed = _snd_pcm_hw_param_first(params, var);
1505         if (changed < 0)
1506                 return changed;
1507         if (params->rmask) {
1508                 int err = snd_pcm_hw_refine(pcm, params);
1509                 if (snd_BUG_ON(err < 0))
1510                         return err;
1511         }
1512         return snd_pcm_hw_param_value(params, var, dir);
1513 }
1514
1515 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1516
1517 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1518                                   snd_pcm_hw_param_t var)
1519 {
1520         int changed;
1521         if (hw_is_mask(var))
1522                 changed = snd_mask_refine_last(hw_param_mask(params, var));
1523         else if (hw_is_interval(var))
1524                 changed = snd_interval_refine_last(hw_param_interval(params, var));
1525         else
1526                 return -EINVAL;
1527         if (changed) {
1528                 params->cmask |= 1 << var;
1529                 params->rmask |= 1 << var;
1530         }
1531         return changed;
1532 }
1533
1534
1535 /**
1536  * snd_pcm_hw_param_last - refine config space and return maximum value
1537  * @pcm: PCM instance
1538  * @params: the hw_params instance
1539  * @var: parameter to retrieve
1540  * @dir: pointer to the direction (-1,0,1) or %NULL
1541  *
1542  * Inside configuration space defined by @params remove from @var all
1543  * values < maximum. Reduce configuration space accordingly.
1544  * Return the maximum.
1545  */
1546 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1547                           struct snd_pcm_hw_params *params,
1548                           snd_pcm_hw_param_t var, int *dir)
1549 {
1550         int changed = _snd_pcm_hw_param_last(params, var);
1551         if (changed < 0)
1552                 return changed;
1553         if (params->rmask) {
1554                 int err = snd_pcm_hw_refine(pcm, params);
1555                 if (snd_BUG_ON(err < 0))
1556                         return err;
1557         }
1558         return snd_pcm_hw_param_value(params, var, dir);
1559 }
1560
1561 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1562
1563 /**
1564  * snd_pcm_hw_param_choose - choose a configuration defined by @params
1565  * @pcm: PCM instance
1566  * @params: the hw_params instance
1567  *
1568  * Choose one configuration from configuration space defined by @params.
1569  * The configuration chosen is that obtained fixing in this order:
1570  * first access, first format, first subformat, min channels,
1571  * min rate, min period time, max buffer size, min tick time
1572  */
1573 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1574                              struct snd_pcm_hw_params *params)
1575 {
1576         static int vars[] = {
1577                 SNDRV_PCM_HW_PARAM_ACCESS,
1578                 SNDRV_PCM_HW_PARAM_FORMAT,
1579                 SNDRV_PCM_HW_PARAM_SUBFORMAT,
1580                 SNDRV_PCM_HW_PARAM_CHANNELS,
1581                 SNDRV_PCM_HW_PARAM_RATE,
1582                 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1583                 SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1584                 SNDRV_PCM_HW_PARAM_TICK_TIME,
1585                 -1
1586         };
1587         int err, *v;
1588
1589         for (v = vars; *v != -1; v++) {
1590                 if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1591                         err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1592                 else
1593                         err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1594                 if (snd_BUG_ON(err < 0))
1595                         return err;
1596         }
1597         return 0;
1598 }
1599
1600 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1601                                    void *arg)
1602 {
1603         struct snd_pcm_runtime *runtime = substream->runtime;
1604         unsigned long flags;
1605         snd_pcm_stream_lock_irqsave(substream, flags);
1606         if (snd_pcm_running(substream) &&
1607             snd_pcm_update_hw_ptr(substream) >= 0)
1608                 runtime->status->hw_ptr %= runtime->buffer_size;
1609         else
1610                 runtime->status->hw_ptr = 0;
1611         snd_pcm_stream_unlock_irqrestore(substream, flags);
1612         return 0;
1613 }
1614
1615 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1616                                           void *arg)
1617 {
1618         struct snd_pcm_channel_info *info = arg;
1619         struct snd_pcm_runtime *runtime = substream->runtime;
1620         int width;
1621         if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1622                 info->offset = -1;
1623                 return 0;
1624         }
1625         width = snd_pcm_format_physical_width(runtime->format);
1626         if (width < 0)
1627                 return width;
1628         info->offset = 0;
1629         switch (runtime->access) {
1630         case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1631         case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1632                 info->first = info->channel * width;
1633                 info->step = runtime->channels * width;
1634                 break;
1635         case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1636         case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1637         {
1638                 size_t size = runtime->dma_bytes / runtime->channels;
1639                 info->first = info->channel * size * 8;
1640                 info->step = width;
1641                 break;
1642         }
1643         default:
1644                 snd_BUG();
1645                 break;
1646         }
1647         return 0;
1648 }
1649
1650 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1651                                        void *arg)
1652 {
1653         struct snd_pcm_hw_params *params = arg;
1654         snd_pcm_format_t format;
1655         int channels, width;
1656
1657         params->fifo_size = substream->runtime->hw.fifo_size;
1658         if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1659                 format = params_format(params);
1660                 channels = params_channels(params);
1661                 width = snd_pcm_format_physical_width(format);
1662                 params->fifo_size /= width * channels;
1663         }
1664         return 0;
1665 }
1666
1667 /**
1668  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1669  * @substream: the pcm substream instance
1670  * @cmd: ioctl command
1671  * @arg: ioctl argument
1672  *
1673  * Processes the generic ioctl commands for PCM.
1674  * Can be passed as the ioctl callback for PCM ops.
1675  *
1676  * Returns zero if successful, or a negative error code on failure.
1677  */
1678 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1679                       unsigned int cmd, void *arg)
1680 {
1681         switch (cmd) {
1682         case SNDRV_PCM_IOCTL1_INFO:
1683                 return 0;
1684         case SNDRV_PCM_IOCTL1_RESET:
1685                 return snd_pcm_lib_ioctl_reset(substream, arg);
1686         case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1687                 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1688         case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1689                 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1690         }
1691         return -ENXIO;
1692 }
1693
1694 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1695
1696 /**
1697  * snd_pcm_period_elapsed - update the pcm status for the next period
1698  * @substream: the pcm substream instance
1699  *
1700  * This function is called from the interrupt handler when the
1701  * PCM has processed the period size.  It will update the current
1702  * pointer, wake up sleepers, etc.
1703  *
1704  * Even if more than one periods have elapsed since the last call, you
1705  * have to call this only once.
1706  */
1707 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1708 {
1709         struct snd_pcm_runtime *runtime;
1710         unsigned long flags;
1711
1712         if (PCM_RUNTIME_CHECK(substream))
1713                 return;
1714         runtime = substream->runtime;
1715
1716         if (runtime->transfer_ack_begin)
1717                 runtime->transfer_ack_begin(substream);
1718
1719         snd_pcm_stream_lock_irqsave(substream, flags);
1720         if (!snd_pcm_running(substream) ||
1721             snd_pcm_update_hw_ptr0(substream, 1) < 0)
1722                 goto _end;
1723
1724         if (substream->timer_running)
1725                 snd_timer_interrupt(substream->timer, 1);
1726  _end:
1727         snd_pcm_stream_unlock_irqrestore(substream, flags);
1728         if (runtime->transfer_ack_end)
1729                 runtime->transfer_ack_end(substream);
1730         kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1731 }
1732
1733 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1734
1735 /*
1736  * Wait until avail_min data becomes available
1737  * Returns a negative error code if any error occurs during operation.
1738  * The available space is stored on availp.  When err = 0 and avail = 0
1739  * on the capture stream, it indicates the stream is in DRAINING state.
1740  */
1741 static int wait_for_avail(struct snd_pcm_substream *substream,
1742                               snd_pcm_uframes_t *availp)
1743 {
1744         struct snd_pcm_runtime *runtime = substream->runtime;
1745         int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1746         wait_queue_t wait;
1747         int err = 0;
1748         snd_pcm_uframes_t avail = 0;
1749         long tout;
1750
1751         init_waitqueue_entry(&wait, current);
1752         add_wait_queue(&runtime->tsleep, &wait);
1753         for (;;) {
1754                 if (signal_pending(current)) {
1755                         err = -ERESTARTSYS;
1756                         break;
1757                 }
1758                 set_current_state(TASK_INTERRUPTIBLE);
1759                 snd_pcm_stream_unlock_irq(substream);
1760                 tout = schedule_timeout(msecs_to_jiffies(10000));
1761                 snd_pcm_stream_lock_irq(substream);
1762                 switch (runtime->status->state) {
1763                 case SNDRV_PCM_STATE_SUSPENDED:
1764                         err = -ESTRPIPE;
1765                         goto _endloop;
1766                 case SNDRV_PCM_STATE_XRUN:
1767                         err = -EPIPE;
1768                         goto _endloop;
1769                 case SNDRV_PCM_STATE_DRAINING:
1770                         if (is_playback)
1771                                 err = -EPIPE;
1772                         else
1773                                 avail = 0; /* indicate draining */
1774                         goto _endloop;
1775                 case SNDRV_PCM_STATE_OPEN:
1776                 case SNDRV_PCM_STATE_SETUP:
1777                 case SNDRV_PCM_STATE_DISCONNECTED:
1778                         err = -EBADFD;
1779                         goto _endloop;
1780                 }
1781                 if (!tout) {
1782                         snd_printd("%s write error (DMA or IRQ trouble?)\n",
1783                                    is_playback ? "playback" : "capture");
1784                         err = -EIO;
1785                         break;
1786                 }
1787                 if (is_playback)
1788                         avail = snd_pcm_playback_avail(runtime);
1789                 else
1790                         avail = snd_pcm_capture_avail(runtime);
1791                 if (avail >= runtime->twake)
1792                         break;
1793         }
1794  _endloop:
1795         remove_wait_queue(&runtime->tsleep, &wait);
1796         *availp = avail;
1797         return err;
1798 }
1799
1800 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1801                                       unsigned int hwoff,
1802                                       unsigned long data, unsigned int off,
1803                                       snd_pcm_uframes_t frames)
1804 {
1805         struct snd_pcm_runtime *runtime = substream->runtime;
1806         int err;
1807         char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1808         if (substream->ops->copy) {
1809                 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1810                         return err;
1811         } else {
1812                 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1813                 if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1814                         return -EFAULT;
1815         }
1816         return 0;
1817 }
1818
1819 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1820                           unsigned long data, unsigned int off,
1821                           snd_pcm_uframes_t size);
1822
1823 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1824                                             unsigned long data,
1825                                             snd_pcm_uframes_t size,
1826                                             int nonblock,
1827                                             transfer_f transfer)
1828 {
1829         struct snd_pcm_runtime *runtime = substream->runtime;
1830         snd_pcm_uframes_t xfer = 0;
1831         snd_pcm_uframes_t offset = 0;
1832         int err = 0;
1833
1834         if (size == 0)
1835                 return 0;
1836
1837         snd_pcm_stream_lock_irq(substream);
1838         switch (runtime->status->state) {
1839         case SNDRV_PCM_STATE_PREPARED:
1840         case SNDRV_PCM_STATE_RUNNING:
1841         case SNDRV_PCM_STATE_PAUSED:
1842                 break;
1843         case SNDRV_PCM_STATE_XRUN:
1844                 err = -EPIPE;
1845                 goto _end_unlock;
1846         case SNDRV_PCM_STATE_SUSPENDED:
1847                 err = -ESTRPIPE;
1848                 goto _end_unlock;
1849         default:
1850                 err = -EBADFD;
1851                 goto _end_unlock;
1852         }
1853
1854         runtime->twake = runtime->control->avail_min ? : 1;
1855         while (size > 0) {
1856                 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1857                 snd_pcm_uframes_t avail;
1858                 snd_pcm_uframes_t cont;
1859                 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1860                         snd_pcm_update_hw_ptr(substream);
1861                 avail = snd_pcm_playback_avail(runtime);
1862                 if (!avail) {
1863                         if (nonblock) {
1864                                 err = -EAGAIN;
1865                                 goto _end_unlock;
1866                         }
1867                         runtime->twake = min_t(snd_pcm_uframes_t, size,
1868                                         runtime->control->avail_min ? : 1);
1869                         err = wait_for_avail(substream, &avail);
1870                         if (err < 0)
1871                                 goto _end_unlock;
1872                 }
1873                 frames = size > avail ? avail : size;
1874                 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1875                 if (frames > cont)
1876                         frames = cont;
1877                 if (snd_BUG_ON(!frames)) {
1878                         runtime->twake = 0;
1879                         snd_pcm_stream_unlock_irq(substream);
1880                         return -EINVAL;
1881                 }
1882                 appl_ptr = runtime->control->appl_ptr;
1883                 appl_ofs = appl_ptr % runtime->buffer_size;
1884                 snd_pcm_stream_unlock_irq(substream);
1885                 err = transfer(substream, appl_ofs, data, offset, frames);
1886                 snd_pcm_stream_lock_irq(substream);
1887                 if (err < 0)
1888                         goto _end_unlock;
1889                 switch (runtime->status->state) {
1890                 case SNDRV_PCM_STATE_XRUN:
1891                         err = -EPIPE;
1892                         goto _end_unlock;
1893                 case SNDRV_PCM_STATE_SUSPENDED:
1894                         err = -ESTRPIPE;
1895                         goto _end_unlock;
1896                 default:
1897                         break;
1898                 }
1899                 appl_ptr += frames;
1900                 if (appl_ptr >= runtime->boundary)
1901                         appl_ptr -= runtime->boundary;
1902                 runtime->control->appl_ptr = appl_ptr;
1903                 if (substream->ops->ack)
1904                         substream->ops->ack(substream);
1905
1906                 offset += frames;
1907                 size -= frames;
1908                 xfer += frames;
1909                 if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1910                     snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1911                         err = snd_pcm_start(substream);
1912                         if (err < 0)
1913                                 goto _end_unlock;
1914                 }
1915         }
1916  _end_unlock:
1917         runtime->twake = 0;
1918         if (xfer > 0 && err >= 0)
1919                 snd_pcm_update_state(substream, runtime);
1920         snd_pcm_stream_unlock_irq(substream);
1921         return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
1922 }
1923
1924 /* sanity-check for read/write methods */
1925 static int pcm_sanity_check(struct snd_pcm_substream *substream)
1926 {
1927         struct snd_pcm_runtime *runtime;
1928         if (PCM_RUNTIME_CHECK(substream))
1929                 return -ENXIO;
1930         runtime = substream->runtime;
1931         if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
1932                 return -EINVAL;
1933         if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1934                 return -EBADFD;
1935         return 0;
1936 }
1937
1938 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
1939 {
1940         struct snd_pcm_runtime *runtime;
1941         int nonblock;
1942         int err;
1943
1944         err = pcm_sanity_check(substream);
1945         if (err < 0)
1946                 return err;
1947         runtime = substream->runtime;
1948         nonblock = !!(substream->f_flags & O_NONBLOCK);
1949
1950         if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
1951             runtime->channels > 1)
1952                 return -EINVAL;
1953         return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
1954                                   snd_pcm_lib_write_transfer);
1955 }
1956
1957 EXPORT_SYMBOL(snd_pcm_lib_write);
1958
1959 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
1960                                        unsigned int hwoff,
1961                                        unsigned long data, unsigned int off,
1962                                        snd_pcm_uframes_t frames)
1963 {
1964         struct snd_pcm_runtime *runtime = substream->runtime;
1965         int err;
1966         void __user **bufs = (void __user **)data;
1967         int channels = runtime->channels;
1968         int c;
1969         if (substream->ops->copy) {
1970                 if (snd_BUG_ON(!substream->ops->silence))
1971                         return -EINVAL;
1972                 for (c = 0; c < channels; ++c, ++bufs) {
1973                         if (*bufs == NULL) {
1974                                 if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
1975                                         return err;
1976                         } else {
1977                                 char __user *buf = *bufs + samples_to_bytes(runtime, off);
1978                                 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
1979                                         return err;
1980                         }
1981                 }
1982         } else {
1983                 /* default transfer behaviour */
1984                 size_t dma_csize = runtime->dma_bytes / channels;
1985                 for (c = 0; c < channels; ++c, ++bufs) {
1986                         char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
1987                         if (*bufs == NULL) {
1988                                 snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
1989                         } else {
1990                                 char __user *buf = *bufs + samples_to_bytes(runtime, off);
1991                                 if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
1992                                         return -EFAULT;
1993                         }
1994                 }
1995         }
1996         return 0;
1997 }
1998
1999 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
2000                                      void __user **bufs,
2001                                      snd_pcm_uframes_t frames)
2002 {
2003         struct snd_pcm_runtime *runtime;
2004         int nonblock;
2005         int err;
2006
2007         err = pcm_sanity_check(substream);
2008         if (err < 0)
2009                 return err;
2010         runtime = substream->runtime;
2011         nonblock = !!(substream->f_flags & O_NONBLOCK);
2012
2013         if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2014                 return -EINVAL;
2015         return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2016                                   nonblock, snd_pcm_lib_writev_transfer);
2017 }
2018
2019 EXPORT_SYMBOL(snd_pcm_lib_writev);
2020
2021 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
2022                                      unsigned int hwoff,
2023                                      unsigned long data, unsigned int off,
2024                                      snd_pcm_uframes_t frames)
2025 {
2026         struct snd_pcm_runtime *runtime = substream->runtime;
2027         int err;
2028         char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2029         if (substream->ops->copy) {
2030                 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2031                         return err;
2032         } else {
2033                 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2034                 if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2035                         return -EFAULT;
2036         }
2037         return 0;
2038 }
2039
2040 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2041                                            unsigned long data,
2042                                            snd_pcm_uframes_t size,
2043                                            int nonblock,
2044                                            transfer_f transfer)
2045 {
2046         struct snd_pcm_runtime *runtime = substream->runtime;
2047         snd_pcm_uframes_t xfer = 0;
2048         snd_pcm_uframes_t offset = 0;
2049         int err = 0;
2050
2051         if (size == 0)
2052                 return 0;
2053
2054         snd_pcm_stream_lock_irq(substream);
2055         switch (runtime->status->state) {
2056         case SNDRV_PCM_STATE_PREPARED:
2057                 if (size >= runtime->start_threshold) {
2058                         err = snd_pcm_start(substream);
2059                         if (err < 0)
2060                                 goto _end_unlock;
2061                 }
2062                 break;
2063         case SNDRV_PCM_STATE_DRAINING:
2064         case SNDRV_PCM_STATE_RUNNING:
2065         case SNDRV_PCM_STATE_PAUSED:
2066                 break;
2067         case SNDRV_PCM_STATE_XRUN:
2068                 err = -EPIPE;
2069                 goto _end_unlock;
2070         case SNDRV_PCM_STATE_SUSPENDED:
2071                 err = -ESTRPIPE;
2072                 goto _end_unlock;
2073         default:
2074                 err = -EBADFD;
2075                 goto _end_unlock;
2076         }
2077
2078         runtime->twake = runtime->control->avail_min ? : 1;
2079         while (size > 0) {
2080                 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2081                 snd_pcm_uframes_t avail;
2082                 snd_pcm_uframes_t cont;
2083                 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2084                         snd_pcm_update_hw_ptr(substream);
2085                 avail = snd_pcm_capture_avail(runtime);
2086                 if (!avail) {
2087                         if (runtime->status->state ==
2088                             SNDRV_PCM_STATE_DRAINING) {
2089                                 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2090                                 goto _end_unlock;
2091                         }
2092                         if (nonblock) {
2093                                 err = -EAGAIN;
2094                                 goto _end_unlock;
2095                         }
2096                         runtime->twake = min_t(snd_pcm_uframes_t, size,
2097                                         runtime->control->avail_min ? : 1);
2098                         err = wait_for_avail(substream, &avail);
2099                         if (err < 0)
2100                                 goto _end_unlock;
2101                         if (!avail)
2102                                 continue; /* draining */
2103                 }
2104                 frames = size > avail ? avail : size;
2105                 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2106                 if (frames > cont)
2107                         frames = cont;
2108                 if (snd_BUG_ON(!frames)) {
2109                         runtime->twake = 0;
2110                         snd_pcm_stream_unlock_irq(substream);
2111                         return -EINVAL;
2112                 }
2113                 appl_ptr = runtime->control->appl_ptr;
2114                 appl_ofs = appl_ptr % runtime->buffer_size;
2115                 snd_pcm_stream_unlock_irq(substream);
2116                 err = transfer(substream, appl_ofs, data, offset, frames);
2117                 snd_pcm_stream_lock_irq(substream);
2118                 if (err < 0)
2119                         goto _end_unlock;
2120                 switch (runtime->status->state) {
2121                 case SNDRV_PCM_STATE_XRUN:
2122                         err = -EPIPE;
2123                         goto _end_unlock;
2124                 case SNDRV_PCM_STATE_SUSPENDED:
2125                         err = -ESTRPIPE;
2126                         goto _end_unlock;
2127                 default:
2128                         break;
2129                 }
2130                 appl_ptr += frames;
2131                 if (appl_ptr >= runtime->boundary)
2132                         appl_ptr -= runtime->boundary;
2133                 runtime->control->appl_ptr = appl_ptr;
2134                 if (substream->ops->ack)
2135                         substream->ops->ack(substream);
2136
2137                 offset += frames;
2138                 size -= frames;
2139                 xfer += frames;
2140         }
2141  _end_unlock:
2142         runtime->twake = 0;
2143         if (xfer > 0 && err >= 0)
2144                 snd_pcm_update_state(substream, runtime);
2145         snd_pcm_stream_unlock_irq(substream);
2146         return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2147 }
2148
2149 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2150 {
2151         struct snd_pcm_runtime *runtime;
2152         int nonblock;
2153         int err;
2154
2155         err = pcm_sanity_check(substream);
2156         if (err < 0)
2157                 return err;
2158         runtime = substream->runtime;
2159         nonblock = !!(substream->f_flags & O_NONBLOCK);
2160         if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2161                 return -EINVAL;
2162         return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2163 }
2164
2165 EXPORT_SYMBOL(snd_pcm_lib_read);
2166
2167 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2168                                       unsigned int hwoff,
2169                                       unsigned long data, unsigned int off,
2170                                       snd_pcm_uframes_t frames)
2171 {
2172         struct snd_pcm_runtime *runtime = substream->runtime;
2173         int err;
2174         void __user **bufs = (void __user **)data;
2175         int channels = runtime->channels;
2176         int c;
2177         if (substream->ops->copy) {
2178                 for (c = 0; c < channels; ++c, ++bufs) {
2179                         char __user *buf;
2180                         if (*bufs == NULL)
2181                                 continue;
2182                         buf = *bufs + samples_to_bytes(runtime, off);
2183                         if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2184                                 return err;
2185                 }
2186         } else {
2187                 snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2188                 for (c = 0; c < channels; ++c, ++bufs) {
2189                         char *hwbuf;
2190                         char __user *buf;
2191                         if (*bufs == NULL)
2192                                 continue;
2193
2194                         hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2195                         buf = *bufs + samples_to_bytes(runtime, off);
2196                         if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2197                                 return -EFAULT;
2198                 }
2199         }
2200         return 0;
2201 }
2202
2203 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2204                                     void __user **bufs,
2205                                     snd_pcm_uframes_t frames)
2206 {
2207         struct snd_pcm_runtime *runtime;
2208         int nonblock;
2209         int err;
2210
2211         err = pcm_sanity_check(substream);
2212         if (err < 0)
2213                 return err;
2214         runtime = substream->runtime;
2215         if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2216                 return -EBADFD;
2217
2218         nonblock = !!(substream->f_flags & O_NONBLOCK);
2219         if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2220                 return -EINVAL;
2221         return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2222 }
2223
2224 EXPORT_SYMBOL(snd_pcm_lib_readv);