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