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 #ifdef CONFIG_SND_DEBUG
 132 void snd_pcm_debug_name(struct snd_pcm_substream *substream,
 133                            char *name, size_t len)
 134 {
 135         snprintf(name, len, "pcmC%dD%d%c:%d",
 136                  substream->pcm->card->number,
 137                  substream->pcm->device,
 138                  substream->stream ? 'c' : 'p',
 139                  substream->number);
 140 }
 141 EXPORT_SYMBOL(snd_pcm_debug_name);
 142 #endif
 143
 144 #define XRUN_DEBUG_BASIC        (1<<0)
 145 #define XRUN_DEBUG_STACK        (1<<1)  /* dump also stack */
 146 #define XRUN_DEBUG_JIFFIESCHECK (1<<2)  /* do jiffies check */
 147 #define XRUN_DEBUG_PERIODUPDATE (1<<3)  /* full period update info */
 148 #define XRUN_DEBUG_HWPTRUPDATE  (1<<4)  /* full hwptr update info */
 149 #define XRUN_DEBUG_LOG          (1<<5)  /* show last 10 positions on err */
 150 #define XRUN_DEBUG_LOGONCE      (1<<6)  /* do above only once */
 151
 152 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 153
 154 #define xrun_debug(substream, mask) \
 155                         ((substream)->pstr->xrun_debug & (mask))
 156 #else
 157 #define xrun_debug(substream, mask)     0
 158 #endif
 159
 160 #define dump_stack_on_xrun(substream) do {                      \
 161                 if (xrun_debug(substream, XRUN_DEBUG_STACK))    \
 162                         dump_stack();                           \
 163         } while (0)
 164
 165 static void xrun(struct snd_pcm_substream *substream)
 166 {
 167         struct snd_pcm_runtime *runtime = substream->runtime;
 168
 169         if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
 170                 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 171         snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 172         if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
 173                 char name[16];
 174                 snd_pcm_debug_name(substream, name, sizeof(name));
 175                 snd_printd(KERN_DEBUG "XRUN: %s\n", name);
 176                 dump_stack_on_xrun(substream);
 177         }
 178 }
 179
 180 #ifdef CONFIG_SND_PCM_XRUN_DEBUG
 181 #define hw_ptr_error(substream, fmt, args...)                           \
 182         do {                                                            \
 183                 if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {          \
 184                         xrun_log_show(substream);                       \
 185                         if (printk_ratelimit()) {                       \
 186                                 snd_printd("PCM: " fmt, ##args);        \
 187                         }                                               \
 188                         dump_stack_on_xrun(substream);                  \
 189                 }                                                       \
 190         } while (0)
 191
 192 #define XRUN_LOG_CNT    10
 193
 194 struct hwptr_log_entry {
 195         unsigned int in_interrupt;
 196         unsigned long jiffies;
 197         snd_pcm_uframes_t pos;
 198         snd_pcm_uframes_t period_size;
 199         snd_pcm_uframes_t buffer_size;
 200         snd_pcm_uframes_t old_hw_ptr;
 201         snd_pcm_uframes_t hw_ptr_base;
 202 };
 203
 204 struct snd_pcm_hwptr_log {
 205         unsigned int idx;
 206         unsigned int hit: 1;
 207         struct hwptr_log_entry entries[XRUN_LOG_CNT];
 208 };
 209
 210 static void xrun_log(struct snd_pcm_substream *substream,
 211                      snd_pcm_uframes_t pos, int in_interrupt)
 212 {
 213         struct snd_pcm_runtime *runtime = substream->runtime;
 214         struct snd_pcm_hwptr_log *log = runtime->hwptr_log;
 215         struct hwptr_log_entry *entry;
 216
 217         if (log == NULL) {
 218                 log = kzalloc(sizeof(*log), GFP_ATOMIC);
 219                 if (log == NULL)
 220                         return;
 221                 runtime->hwptr_log = log;
 222         } else {
 223                 if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
 224                         return;
 225         }
 226         entry = &log->entries[log->idx];
 227         entry->in_interrupt = in_interrupt;
 228         entry->jiffies = jiffies;
 229         entry->pos = pos;
 230         entry->period_size = runtime->period_size;
 231         entry->buffer_size = runtime->buffer_size;
 232         entry->old_hw_ptr = runtime->status->hw_ptr;
 233         entry->hw_ptr_base = runtime->hw_ptr_base;
 234         log->idx = (log->idx + 1) % XRUN_LOG_CNT;
 235 }
 236
 237 static void xrun_log_show(struct snd_pcm_substream *substream)
 238 {
 239         struct snd_pcm_hwptr_log *log = substream->runtime->hwptr_log;
 240         struct hwptr_log_entry *entry;
 241         char name[16];
 242         unsigned int idx;
 243         int cnt;
 244
 245         if (log == NULL)
 246                 return;
 247         if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
 248                 return;
 249         snd_pcm_debug_name(substream, name, sizeof(name));
 250         for (cnt = 0, idx = log->idx; cnt < XRUN_LOG_CNT; cnt++) {
 251                 entry = &log->entries[idx];
 252                 if (entry->period_size == 0)
 253                         break;
 254                 snd_printd("hwptr log: %s: %sj=%lu, pos=%ld/%ld/%ld, "
 255                            "hwptr=%ld/%ld\n",
 256                            name, entry->in_interrupt ? "[Q] " : "",
 257                            entry->jiffies,
 258                            (unsigned long)entry->pos,
 259                            (unsigned long)entry->period_size,
 260                            (unsigned long)entry->buffer_size,
 261                            (unsigned long)entry->old_hw_ptr,
 262                            (unsigned long)entry->hw_ptr_base);
 263                 idx++;
 264                 idx %= XRUN_LOG_CNT;
 265         }
 266         log->hit = 1;
 267 }
 268
 269 #else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
 270
 271 #define hw_ptr_error(substream, fmt, args...) do { } while (0)
 272 #define xrun_log(substream, pos, in_interrupt)  do { } while (0)
 273 #define xrun_log_show(substream)        do { } while (0)
 274
 275 #endif
 276
 277 int snd_pcm_update_state(struct snd_pcm_substream *substream,
 278                          struct snd_pcm_runtime *runtime)
 279 {
 280         snd_pcm_uframes_t avail;
 281
 282         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 283                 avail = snd_pcm_playback_avail(runtime);
 284         else
 285                 avail = snd_pcm_capture_avail(runtime);
 286         if (avail > runtime->avail_max)
 287                 runtime->avail_max = avail;
 288         if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
 289                 if (avail >= runtime->buffer_size) {
 290                         snd_pcm_drain_done(substream);
 291                         return -EPIPE;
 292                 }
 293         } else {
 294                 if (avail >= runtime->stop_threshold) {
 295                         xrun(substream);
 296                         return -EPIPE;
 297                 }
 298         }
 299         if (runtime->twake) {
 300                 if (avail >= runtime->twake)
 301                         wake_up(&runtime->tsleep);
 302         } else if (avail >= runtime->control->avail_min)
 303                 wake_up(&runtime->sleep);
 304         return 0;
 305 }
 306
 307 static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
 308                                   unsigned int in_interrupt)
 309 {
 310         struct snd_pcm_runtime *runtime = substream->runtime;
 311         snd_pcm_uframes_t pos;
 312         snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
 313         snd_pcm_sframes_t hdelta, delta;
 314         unsigned long jdelta;
 315
 316         old_hw_ptr = runtime->status->hw_ptr;
 317         pos = substream->ops->pointer(substream);
 318         if (pos == SNDRV_PCM_POS_XRUN) {
 319                 xrun(substream);
 320                 return -EPIPE;
 321         }
 322         if (pos >= runtime->buffer_size) {
 323                 if (printk_ratelimit()) {
 324                         char name[16];
 325                         snd_pcm_debug_name(substream, name, sizeof(name));
 326                         xrun_log_show(substream);
 327                         snd_printd(KERN_ERR  "BUG: %s, pos = %ld, "
 328                                    "buffer size = %ld, period size = %ld\n",
 329                                    name, pos, runtime->buffer_size,
 330                                    runtime->period_size);
 331                 }
 332                 pos = 0;
 333         }
 334         pos -= pos % runtime->min_align;
 335         if (xrun_debug(substream, XRUN_DEBUG_LOG))
 336                 xrun_log(substream, pos, in_interrupt);
 337         hw_base = runtime->hw_ptr_base;
 338         new_hw_ptr = hw_base + pos;
 339         if (in_interrupt) {
 340                 /* we know that one period was processed */
 341                 /* delta = "expected next hw_ptr" for in_interrupt != 0 */
 342                 delta = runtime->hw_ptr_interrupt + runtime->period_size;
 343                 if (delta > new_hw_ptr) {
 344                         /* check for double acknowledged interrupts */
 345                         hdelta = jiffies - runtime->hw_ptr_jiffies;
 346                         if (hdelta > runtime->hw_ptr_buffer_jiffies/2) {
 347                                 hw_base += runtime->buffer_size;
 348                                 if (hw_base >= runtime->boundary)
 349                                         hw_base = 0;
 350                                 new_hw_ptr = hw_base + pos;
 351                                 goto __delta;
 352                         }
 353                 }
 354         }
 355         /* new_hw_ptr might be lower than old_hw_ptr in case when */
 356         /* pointer crosses the end of the ring buffer */
 357         if (new_hw_ptr < old_hw_ptr) {
 358                 hw_base += runtime->buffer_size;
 359                 if (hw_base >= runtime->boundary)
 360                         hw_base = 0;
 361                 new_hw_ptr = hw_base + pos;
 362         }
 363       __delta:
 364         delta = new_hw_ptr - old_hw_ptr;
 365         if (delta < 0)
 366                 delta += runtime->boundary;
 367         if (xrun_debug(substream, in_interrupt ?
 368                         XRUN_DEBUG_PERIODUPDATE : XRUN_DEBUG_HWPTRUPDATE)) {
 369                 char name[16];
 370                 snd_pcm_debug_name(substream, name, sizeof(name));
 371                 snd_printd("%s_update: %s: pos=%u/%u/%u, "
 372                            "hwptr=%ld/%ld/%ld/%ld\n",
 373                            in_interrupt ? "period" : "hwptr",
 374                            name,
 375                            (unsigned int)pos,
 376                            (unsigned int)runtime->period_size,
 377                            (unsigned int)runtime->buffer_size,
 378                            (unsigned long)delta,
 379                            (unsigned long)old_hw_ptr,
 380                            (unsigned long)new_hw_ptr,
 381                            (unsigned long)runtime->hw_ptr_base);
 382         }
 383
 384         if (runtime->no_period_wakeup) {
 385                 snd_pcm_sframes_t xrun_threshold;
 386                 /*
 387                  * Without regular period interrupts, we have to check
 388                  * the elapsed time to detect xruns.
 389                  */
 390                 jdelta = jiffies - runtime->hw_ptr_jiffies;
 391                 if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
 392                         goto no_delta_check;
 393                 hdelta = jdelta - delta * HZ / runtime->rate;
 394                 xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
 395                 while (hdelta > xrun_threshold) {
 396                         delta += runtime->buffer_size;
 397                         hw_base += runtime->buffer_size;
 398                         if (hw_base >= runtime->boundary)
 399                                 hw_base = 0;
 400                         new_hw_ptr = hw_base + pos;
 401                         hdelta -= runtime->hw_ptr_buffer_jiffies;
 402                 }
 403                 goto no_delta_check;
 404         }
 405
 406         /* something must be really wrong */
 407         if (delta >= runtime->buffer_size + runtime->period_size) {
 408                 hw_ptr_error(substream,
 409                                "Unexpected hw_pointer value %s"
 410                                "(stream=%i, pos=%ld, new_hw_ptr=%ld, "
 411                                "old_hw_ptr=%ld)\n",
 412                                      in_interrupt ? "[Q] " : "[P]",
 413                                      substream->stream, (long)pos,
 414                                      (long)new_hw_ptr, (long)old_hw_ptr);
 415                 return 0;
 416         }
 417
 418         /* Do jiffies check only in xrun_debug mode */
 419         if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
 420                 goto no_jiffies_check;
 421
 422         /* Skip the jiffies check for hardwares with BATCH flag.
 423          * Such hardware usually just increases the position at each IRQ,
 424          * thus it can't give any strange position.
 425          */
 426         if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
 427                 goto no_jiffies_check;
 428         hdelta = delta;
 429         if (hdelta < runtime->delay)
 430                 goto no_jiffies_check;
 431         hdelta -= runtime->delay;
 432         jdelta = jiffies - runtime->hw_ptr_jiffies;
 433         if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
 434                 delta = jdelta /
 435                         (((runtime->period_size * HZ) / runtime->rate)
 436                                                                 + HZ/100);
 437                 /* move new_hw_ptr according jiffies not pos variable */
 438                 new_hw_ptr = old_hw_ptr;
 439                 hw_base = delta;
 440                 /* use loop to avoid checks for delta overflows */
 441                 /* the delta value is small or zero in most cases */
 442                 while (delta > 0) {
 443                         new_hw_ptr += runtime->period_size;
 444                         if (new_hw_ptr >= runtime->boundary)
 445                                 new_hw_ptr -= runtime->boundary;
 446                         delta--;
 447                 }
 448                 /* align hw_base to buffer_size */
 449                 hw_ptr_error(substream,
 450                              "hw_ptr skipping! %s"
 451                              "(pos=%ld, delta=%ld, period=%ld, "
 452                              "jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
 453                              in_interrupt ? "[Q] " : "",
 454                              (long)pos, (long)hdelta,
 455                              (long)runtime->period_size, jdelta,
 456                              ((hdelta * HZ) / runtime->rate), hw_base,
 457                              (unsigned long)old_hw_ptr,
 458                              (unsigned long)new_hw_ptr);
 459                 /* reset values to proper state */
 460                 delta = 0;
 461                 hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
 462         }
 463  no_jiffies_check:
 464         if (delta > runtime->period_size + runtime->period_size / 2) {
 465                 hw_ptr_error(substream,
 466                              "Lost interrupts? %s"
 467                              "(stream=%i, delta=%ld, new_hw_ptr=%ld, "
 468                              "old_hw_ptr=%ld)\n",
 469                              in_interrupt ? "[Q] " : "",
 470                              substream->stream, (long)delta,
 471                              (long)new_hw_ptr,
 472                              (long)old_hw_ptr);
 473         }
 474
 475  no_delta_check:
 476         if (runtime->status->hw_ptr == new_hw_ptr)
 477                 return 0;
 478
 479         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 480             runtime->silence_size > 0)
 481                 snd_pcm_playback_silence(substream, new_hw_ptr);
 482
 483         if (in_interrupt) {
 484                 delta = new_hw_ptr - runtime->hw_ptr_interrupt;
 485                 if (delta < 0)
 486                         delta += runtime->boundary;
 487                 delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
 488                 runtime->hw_ptr_interrupt += delta;
 489                 if (runtime->hw_ptr_interrupt >= runtime->boundary)
 490                         runtime->hw_ptr_interrupt -= runtime->boundary;
 491         }
 492         runtime->hw_ptr_base = hw_base;
 493         runtime->status->hw_ptr = new_hw_ptr;
 494         runtime->hw_ptr_jiffies = jiffies;
 495         if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
 496                 snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 497
 498         return snd_pcm_update_state(substream, runtime);
 499 }
 500
 501 /* CAUTION: call it with irq disabled */
 502 int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
 503 {
 504         return snd_pcm_update_hw_ptr0(substream, 0);
 505 }
 506
 507 /**
 508  * snd_pcm_set_ops - set the PCM operators
 509  * @pcm: the pcm instance
 510  * @direction: stream direction, SNDRV_PCM_STREAM_XXX
 511  * @ops: the operator table
 512  *
 513  * Sets the given PCM operators to the pcm instance.
 514  */
 515 void snd_pcm_set_ops(struct snd_pcm *pcm, int direction, struct snd_pcm_ops *ops)
 516 {
 517         struct snd_pcm_str *stream = &pcm->streams[direction];
 518         struct snd_pcm_substream *substream;
 519
 520         for (substream = stream->substream; substream != NULL; substream = substream->next)
 521                 substream->ops = ops;
 522 }
 523
 524 EXPORT_SYMBOL(snd_pcm_set_ops);
 525
 526 /**
 527  * snd_pcm_sync - set the PCM sync id
 528  * @substream: the pcm substream
 529  *
 530  * Sets the PCM sync identifier for the card.
 531  */
 532 void snd_pcm_set_sync(struct snd_pcm_substream *substream)
 533 {
 534         struct snd_pcm_runtime *runtime = substream->runtime;
 535
 536         runtime->sync.id32[0] = substream->pcm->card->number;
 537         runtime->sync.id32[1] = -1;
 538         runtime->sync.id32[2] = -1;
 539         runtime->sync.id32[3] = -1;
 540 }
 541
 542 EXPORT_SYMBOL(snd_pcm_set_sync);
 543
 544 /*
 545  *  Standard ioctl routine
 546  */
 547
 548 static inline unsigned int div32(unsigned int a, unsigned int b,
 549                                  unsigned int *r)
 550 {
 551         if (b == 0) {
 552                 *r = 0;
 553                 return UINT_MAX;
 554         }
 555         *r = a % b;
 556         return a / b;
 557 }
 558
 559 static inline unsigned int div_down(unsigned int a, unsigned int b)
 560 {
 561         if (b == 0)
 562                 return UINT_MAX;
 563         return a / b;
 564 }
 565
 566 static inline unsigned int div_up(unsigned int a, unsigned int b)
 567 {
 568         unsigned int r;
 569         unsigned int q;
 570         if (b == 0)
 571                 return UINT_MAX;
 572         q = div32(a, b, &r);
 573         if (r)
 574                 ++q;
 575         return q;
 576 }
 577
 578 static inline unsigned int mul(unsigned int a, unsigned int b)
 579 {
 580         if (a == 0)
 581                 return 0;
 582         if (div_down(UINT_MAX, a) < b)
 583                 return UINT_MAX;
 584         return a * b;
 585 }
 586
 587 static inline unsigned int muldiv32(unsigned int a, unsigned int b,
 588                                     unsigned int c, unsigned int *r)
 589 {
 590         u_int64_t n = (u_int64_t) a * b;
 591         if (c == 0) {
 592                 snd_BUG_ON(!n);
 593                 *r = 0;
 594                 return UINT_MAX;
 595         }
 596         n = div_u64_rem(n, c, r);
 597         if (n >= UINT_MAX) {
 598                 *r = 0;
 599                 return UINT_MAX;
 600         }
 601         return n;
 602 }
 603
 604 /**
 605  * snd_interval_refine - refine the interval value of configurator
 606  * @i: the interval value to refine
 607  * @v: the interval value to refer to
 608  *
 609  * Refines the interval value with the reference value.
 610  * The interval is changed to the range satisfying both intervals.
 611  * The interval status (min, max, integer, etc.) are evaluated.
 612  *
 613  * Returns non-zero if the value is changed, zero if not changed.
 614  */
 615 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
 616 {
 617         int changed = 0;
 618         if (snd_BUG_ON(snd_interval_empty(i)))
 619                 return -EINVAL;
 620         if (i->min < v->min) {
 621                 i->min = v->min;
 622                 i->openmin = v->openmin;
 623                 changed = 1;
 624         } else if (i->min == v->min && !i->openmin && v->openmin) {
 625                 i->openmin = 1;
 626                 changed = 1;
 627         }
 628         if (i->max > v->max) {
 629                 i->max = v->max;
 630                 i->openmax = v->openmax;
 631                 changed = 1;
 632         } else if (i->max == v->max && !i->openmax && v->openmax) {
 633                 i->openmax = 1;
 634                 changed = 1;
 635         }
 636         if (!i->integer && v->integer) {
 637                 i->integer = 1;
 638                 changed = 1;
 639         }
 640         if (i->integer) {
 641                 if (i->openmin) {
 642                         i->min++;
 643                         i->openmin = 0;
 644                 }
 645                 if (i->openmax) {
 646                         i->max--;
 647                         i->openmax = 0;
 648                 }
 649         } else if (!i->openmin && !i->openmax && i->min == i->max)
 650                 i->integer = 1;
 651         if (snd_interval_checkempty(i)) {
 652                 snd_interval_none(i);
 653                 return -EINVAL;
 654         }
 655         return changed;
 656 }
 657
 658 EXPORT_SYMBOL(snd_interval_refine);
 659
 660 static int snd_interval_refine_first(struct snd_interval *i)
 661 {
 662         if (snd_BUG_ON(snd_interval_empty(i)))
 663                 return -EINVAL;
 664         if (snd_interval_single(i))
 665                 return 0;
 666         i->max = i->min;
 667         i->openmax = i->openmin;
 668         if (i->openmax)
 669                 i->max++;
 670         return 1;
 671 }
 672
 673 static int snd_interval_refine_last(struct snd_interval *i)
 674 {
 675         if (snd_BUG_ON(snd_interval_empty(i)))
 676                 return -EINVAL;
 677         if (snd_interval_single(i))
 678                 return 0;
 679         i->min = i->max;
 680         i->openmin = i->openmax;
 681         if (i->openmin)
 682                 i->min--;
 683         return 1;
 684 }
 685
 686 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 687 {
 688         if (a->empty || b->empty) {
 689                 snd_interval_none(c);
 690                 return;
 691         }
 692         c->empty = 0;
 693         c->min = mul(a->min, b->min);
 694         c->openmin = (a->openmin || b->openmin);
 695         c->max = mul(a->max,  b->max);
 696         c->openmax = (a->openmax || b->openmax);
 697         c->integer = (a->integer && b->integer);
 698 }
 699
 700 /**
 701  * snd_interval_div - refine the interval value with division
 702  * @a: dividend
 703  * @b: divisor
 704  * @c: quotient
 705  *
 706  * c = a / b
 707  *
 708  * Returns non-zero if the value is changed, zero if not changed.
 709  */
 710 void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 711 {
 712         unsigned int r;
 713         if (a->empty || b->empty) {
 714                 snd_interval_none(c);
 715                 return;
 716         }
 717         c->empty = 0;
 718         c->min = div32(a->min, b->max, &r);
 719         c->openmin = (r || a->openmin || b->openmax);
 720         if (b->min > 0) {
 721                 c->max = div32(a->max, b->min, &r);
 722                 if (r) {
 723                         c->max++;
 724                         c->openmax = 1;
 725                 } else
 726                         c->openmax = (a->openmax || b->openmin);
 727         } else {
 728                 c->max = UINT_MAX;
 729                 c->openmax = 0;
 730         }
 731         c->integer = 0;
 732 }
 733
 734 /**
 735  * snd_interval_muldivk - refine the interval value
 736  * @a: dividend 1
 737  * @b: dividend 2
 738  * @k: divisor (as integer)
 739  * @c: result
 740   *
 741  * c = a * b / k
 742  *
 743  * Returns non-zero if the value is changed, zero if not changed.
 744  */
 745 void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
 746                       unsigned int k, 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, b->min, k, &r);
 755         c->openmin = (r || a->openmin || b->openmin);
 756         c->max = muldiv32(a->max, b->max, k, &r);
 757         if (r) {
 758                 c->max++;
 759                 c->openmax = 1;
 760         } else
 761                 c->openmax = (a->openmax || b->openmax);
 762         c->integer = 0;
 763 }
 764
 765 /**
 766  * snd_interval_mulkdiv - refine the interval value
 767  * @a: dividend 1
 768  * @k: dividend 2 (as integer)
 769  * @b: divisor
 770  * @c: result
 771  *
 772  * c = a * k / b
 773  *
 774  * Returns non-zero if the value is changed, zero if not changed.
 775  */
 776 void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
 777                       const struct snd_interval *b, struct snd_interval *c)
 778 {
 779         unsigned int r;
 780         if (a->empty || b->empty) {
 781                 snd_interval_none(c);
 782                 return;
 783         }
 784         c->empty = 0;
 785         c->min = muldiv32(a->min, k, b->max, &r);
 786         c->openmin = (r || a->openmin || b->openmax);
 787         if (b->min > 0) {
 788                 c->max = muldiv32(a->max, k, b->min, &r);
 789                 if (r) {
 790                         c->max++;
 791                         c->openmax = 1;
 792                 } else
 793                         c->openmax = (a->openmax || b->openmin);
 794         } else {
 795                 c->max = UINT_MAX;
 796                 c->openmax = 0;
 797         }
 798         c->integer = 0;
 799 }
 800
 801 /* ---- */
 802
 803
 804 /**
 805  * snd_interval_ratnum - refine the interval value
 806  * @i: interval to refine
 807  * @rats_count: number of ratnum_t
 808  * @rats: ratnum_t array
 809  * @nump: pointer to store the resultant numerator
 810  * @denp: pointer to store the resultant denominator
 811  *
 812  * Returns non-zero if the value is changed, zero if not changed.
 813  */
 814 int snd_interval_ratnum(struct snd_interval *i,
 815                         unsigned int rats_count, struct snd_ratnum *rats,
 816                         unsigned int *nump, unsigned int *denp)
 817 {
 818         unsigned int best_num, best_den;
 819         int best_diff;
 820         unsigned int k;
 821         struct snd_interval t;
 822         int err;
 823         unsigned int result_num, result_den;
 824         int result_diff;
 825
 826         best_num = best_den = best_diff = 0;
 827         for (k = 0; k < rats_count; ++k) {
 828                 unsigned int num = rats[k].num;
 829                 unsigned int den;
 830                 unsigned int q = i->min;
 831                 int diff;
 832                 if (q == 0)
 833                         q = 1;
 834                 den = div_up(num, q);
 835                 if (den < rats[k].den_min)
 836                         continue;
 837                 if (den > rats[k].den_max)
 838                         den = rats[k].den_max;
 839                 else {
 840                         unsigned int r;
 841                         r = (den - rats[k].den_min) % rats[k].den_step;
 842                         if (r != 0)
 843                                 den -= r;
 844                 }
 845                 diff = num - q * den;
 846                 if (diff < 0)
 847                         diff = -diff;
 848                 if (best_num == 0 ||
 849                     diff * best_den < best_diff * den) {
 850                         best_diff = diff;
 851                         best_den = den;
 852                         best_num = num;
 853                 }
 854         }
 855         if (best_den == 0) {
 856                 i->empty = 1;
 857                 return -EINVAL;
 858         }
 859         t.min = div_down(best_num, best_den);
 860         t.openmin = !!(best_num % best_den);
 861
 862         result_num = best_num;
 863         result_diff = best_diff;
 864         result_den = best_den;
 865         best_num = best_den = best_diff = 0;
 866         for (k = 0; k < rats_count; ++k) {
 867                 unsigned int num = rats[k].num;
 868                 unsigned int den;
 869                 unsigned int q = i->max;
 870                 int diff;
 871                 if (q == 0) {
 872                         i->empty = 1;
 873                         return -EINVAL;
 874                 }
 875                 den = div_down(num, q);
 876                 if (den > rats[k].den_max)
 877                         continue;
 878                 if (den < rats[k].den_min)
 879                         den = rats[k].den_min;
 880                 else {
 881                         unsigned int r;
 882                         r = (den - rats[k].den_min) % rats[k].den_step;
 883                         if (r != 0)
 884                                 den += rats[k].den_step - r;
 885                 }
 886                 diff = q * den - num;
 887                 if (diff < 0)
 888                         diff = -diff;
 889                 if (best_num == 0 ||
 890                     diff * best_den < best_diff * den) {
 891                         best_diff = diff;
 892                         best_den = den;
 893                         best_num = num;
 894                 }
 895         }
 896         if (best_den == 0) {
 897                 i->empty = 1;
 898                 return -EINVAL;
 899         }
 900         t.max = div_up(best_num, best_den);
 901         t.openmax = !!(best_num % best_den);
 902         t.integer = 0;
 903         err = snd_interval_refine(i, &t);
 904         if (err < 0)
 905                 return err;
 906
 907         if (snd_interval_single(i)) {
 908                 if (best_diff * result_den < result_diff * best_den) {
 909                         result_num = best_num;
 910                         result_den = best_den;
 911                 }
 912                 if (nump)
 913                         *nump = result_num;
 914                 if (denp)
 915                         *denp = result_den;
 916         }
 917         return err;
 918 }
 919
 920 EXPORT_SYMBOL(snd_interval_ratnum);
 921
 922 /**
 923  * snd_interval_ratden - refine the interval value
 924  * @i: interval to refine
 925  * @rats_count: number of struct ratden
 926  * @rats: struct ratden array
 927  * @nump: pointer to store the resultant numerator
 928  * @denp: pointer to store the resultant denominator
 929  *
 930  * Returns non-zero if the value is changed, zero if not changed.
 931  */
 932 static int snd_interval_ratden(struct snd_interval *i,
 933                                unsigned int rats_count, struct snd_ratden *rats,
 934                                unsigned int *nump, unsigned int *denp)
 935 {
 936         unsigned int best_num, best_diff, best_den;
 937         unsigned int k;
 938         struct snd_interval t;
 939         int err;
 940
 941         best_num = best_den = best_diff = 0;
 942         for (k = 0; k < rats_count; ++k) {
 943                 unsigned int num;
 944                 unsigned int den = rats[k].den;
 945                 unsigned int q = i->min;
 946                 int diff;
 947                 num = mul(q, den);
 948                 if (num > rats[k].num_max)
 949                         continue;
 950                 if (num < rats[k].num_min)
 951                         num = rats[k].num_max;
 952                 else {
 953                         unsigned int r;
 954                         r = (num - rats[k].num_min) % rats[k].num_step;
 955                         if (r != 0)
 956                                 num += rats[k].num_step - r;
 957                 }
 958                 diff = num - q * den;
 959                 if (best_num == 0 ||
 960                     diff * best_den < best_diff * den) {
 961                         best_diff = diff;
 962                         best_den = den;
 963                         best_num = num;
 964                 }
 965         }
 966         if (best_den == 0) {
 967                 i->empty = 1;
 968                 return -EINVAL;
 969         }
 970         t.min = div_down(best_num, best_den);
 971         t.openmin = !!(best_num % best_den);
 972
 973         best_num = best_den = best_diff = 0;
 974         for (k = 0; k < rats_count; ++k) {
 975                 unsigned int num;
 976                 unsigned int den = rats[k].den;
 977                 unsigned int q = i->max;
 978                 int diff;
 979                 num = mul(q, den);
 980                 if (num < rats[k].num_min)
 981                         continue;
 982                 if (num > rats[k].num_max)
 983                         num = rats[k].num_max;
 984                 else {
 985                         unsigned int r;
 986                         r = (num - rats[k].num_min) % rats[k].num_step;
 987                         if (r != 0)
 988                                 num -= r;
 989                 }
 990                 diff = q * den - num;
 991                 if (best_num == 0 ||
 992                     diff * best_den < best_diff * den) {
 993                         best_diff = diff;
 994                         best_den = den;
 995                         best_num = num;
 996                 }
 997         }
 998         if (best_den == 0) {
 999                 i->empty = 1;
1000                 return -EINVAL;
1001         }
1002         t.max = div_up(best_num, best_den);
1003         t.openmax = !!(best_num % best_den);
1004         t.integer = 0;
1005         err = snd_interval_refine(i, &t);
1006         if (err < 0)
1007                 return err;
1008
1009         if (snd_interval_single(i)) {
1010                 if (nump)
1011                         *nump = best_num;
1012                 if (denp)
1013                         *denp = best_den;
1014         }
1015         return err;
1016 }
1017
1018 /**
1019  * snd_interval_list - refine the interval value from the list
1020  * @i: the interval value to refine
1021  * @count: the number of elements in the list
1022  * @list: the value list
1023  * @mask: the bit-mask to evaluate
1024  *
1025  * Refines the interval value from the list.
1026  * When mask is non-zero, only the elements corresponding to bit 1 are
1027  * evaluated.
1028  *
1029  * Returns non-zero if the value is changed, zero if not changed.
1030  */
1031 int snd_interval_list(struct snd_interval *i, unsigned int count, unsigned int *list, unsigned int mask)
1032 {
1033         unsigned int k;
1034         struct snd_interval list_range;
1035
1036         if (!count) {
1037                 i->empty = 1;
1038                 return -EINVAL;
1039         }
1040         snd_interval_any(&list_range);
1041         list_range.min = UINT_MAX;
1042         list_range.max = 0;
1043         for (k = 0; k < count; k++) {
1044                 if (mask && !(mask & (1 << k)))
1045                         continue;
1046                 if (!snd_interval_test(i, list[k]))
1047                         continue;
1048                 list_range.min = min(list_range.min, list[k]);
1049                 list_range.max = max(list_range.max, list[k]);
1050         }
1051         return snd_interval_refine(i, &list_range);
1052 }
1053
1054 EXPORT_SYMBOL(snd_interval_list);
1055
1056 static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
1057 {
1058         unsigned int n;
1059         int changed = 0;
1060         n = (i->min - min) % step;
1061         if (n != 0 || i->openmin) {
1062                 i->min += step - n;
1063                 changed = 1;
1064         }
1065         n = (i->max - min) % step;
1066         if (n != 0 || i->openmax) {
1067                 i->max -= n;
1068                 changed = 1;
1069         }
1070         if (snd_interval_checkempty(i)) {
1071                 i->empty = 1;
1072                 return -EINVAL;
1073         }
1074         return changed;
1075 }
1076
1077 /* Info constraints helpers */
1078
1079 /**
1080  * snd_pcm_hw_rule_add - add the hw-constraint rule
1081  * @runtime: the pcm runtime instance
1082  * @cond: condition bits
1083  * @var: the variable to evaluate
1084  * @func: the evaluation function
1085  * @private: the private data pointer passed to function
1086  * @dep: the dependent variables
1087  *
1088  * Returns zero if successful, or a negative error code on failure.
1089  */
1090 int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1091                         int var,
1092                         snd_pcm_hw_rule_func_t func, void *private,
1093                         int dep, ...)
1094 {
1095         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1096         struct snd_pcm_hw_rule *c;
1097         unsigned int k;
1098         va_list args;
1099         va_start(args, dep);
1100         if (constrs->rules_num >= constrs->rules_all) {
1101                 struct snd_pcm_hw_rule *new;
1102                 unsigned int new_rules = constrs->rules_all + 16;
1103                 new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1104                 if (!new) {
1105                         va_end(args);
1106                         return -ENOMEM;
1107                 }
1108                 if (constrs->rules) {
1109                         memcpy(new, constrs->rules,
1110                                constrs->rules_num * sizeof(*c));
1111                         kfree(constrs->rules);
1112                 }
1113                 constrs->rules = new;
1114                 constrs->rules_all = new_rules;
1115         }
1116         c = &constrs->rules[constrs->rules_num];
1117         c->cond = cond;
1118         c->func = func;
1119         c->var = var;
1120         c->private = private;
1121         k = 0;
1122         while (1) {
1123                 if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1124                         va_end(args);
1125                         return -EINVAL;
1126                 }
1127                 c->deps[k++] = dep;
1128                 if (dep < 0)
1129                         break;
1130                 dep = va_arg(args, int);
1131         }
1132         constrs->rules_num++;
1133         va_end(args);
1134         return 0;
1135 }
1136
1137 EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1138
1139 /**
1140  * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1141  * @runtime: PCM runtime instance
1142  * @var: hw_params variable to apply the mask
1143  * @mask: the bitmap mask
1144  *
1145  * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1146  */
1147 int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1148                                u_int32_t mask)
1149 {
1150         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1151         struct snd_mask *maskp = constrs_mask(constrs, var);
1152         *maskp->bits &= mask;
1153         memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1154         if (*maskp->bits == 0)
1155                 return -EINVAL;
1156         return 0;
1157 }
1158
1159 /**
1160  * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1161  * @runtime: PCM runtime instance
1162  * @var: hw_params variable to apply the mask
1163  * @mask: the 64bit bitmap mask
1164  *
1165  * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1166  */
1167 int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1168                                  u_int64_t mask)
1169 {
1170         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1171         struct snd_mask *maskp = constrs_mask(constrs, var);
1172         maskp->bits[0] &= (u_int32_t)mask;
1173         maskp->bits[1] &= (u_int32_t)(mask >> 32);
1174         memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1175         if (! maskp->bits[0] && ! maskp->bits[1])
1176                 return -EINVAL;
1177         return 0;
1178 }
1179
1180 /**
1181  * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1182  * @runtime: PCM runtime instance
1183  * @var: hw_params variable to apply the integer constraint
1184  *
1185  * Apply the constraint of integer to an interval parameter.
1186  */
1187 int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1188 {
1189         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1190         return snd_interval_setinteger(constrs_interval(constrs, var));
1191 }
1192
1193 EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1194
1195 /**
1196  * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1197  * @runtime: PCM runtime instance
1198  * @var: hw_params variable to apply the range
1199  * @min: the minimal value
1200  * @max: the maximal value
1201  *
1202  * Apply the min/max range constraint to an interval parameter.
1203  */
1204 int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1205                                  unsigned int min, unsigned int max)
1206 {
1207         struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1208         struct snd_interval t;
1209         t.min = min;
1210         t.max = max;
1211         t.openmin = t.openmax = 0;
1212         t.integer = 0;
1213         return snd_interval_refine(constrs_interval(constrs, var), &t);
1214 }
1215
1216 EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1217
1218 static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1219                                 struct snd_pcm_hw_rule *rule)
1220 {
1221         struct snd_pcm_hw_constraint_list *list = rule->private;
1222         return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1223 }
1224
1225
1226 /**
1227  * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1228  * @runtime: PCM runtime instance
1229  * @cond: condition bits
1230  * @var: hw_params variable to apply the list constraint
1231  * @l: list
1232  *
1233  * Apply the list of constraints to an interval parameter.
1234  */
1235 int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1236                                unsigned int cond,
1237                                snd_pcm_hw_param_t var,
1238                                struct snd_pcm_hw_constraint_list *l)
1239 {
1240         return snd_pcm_hw_rule_add(runtime, cond, var,
1241                                    snd_pcm_hw_rule_list, l,
1242                                    var, -1);
1243 }
1244
1245 EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1246
1247 static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1248                                    struct snd_pcm_hw_rule *rule)
1249 {
1250         struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1251         unsigned int num = 0, den = 0;
1252         int err;
1253         err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1254                                   r->nrats, r->rats, &num, &den);
1255         if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1256                 params->rate_num = num;
1257                 params->rate_den = den;
1258         }
1259         return err;
1260 }
1261
1262 /**
1263  * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1264  * @runtime: PCM runtime instance
1265  * @cond: condition bits
1266  * @var: hw_params variable to apply the ratnums constraint
1267  * @r: struct snd_ratnums constriants
1268  */
1269 int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime,
1270                                   unsigned int cond,
1271                                   snd_pcm_hw_param_t var,
1272                                   struct snd_pcm_hw_constraint_ratnums *r)
1273 {
1274         return snd_pcm_hw_rule_add(runtime, cond, var,
1275                                    snd_pcm_hw_rule_ratnums, r,
1276                                    var, -1);
1277 }
1278
1279 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1280
1281 static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1282                                    struct snd_pcm_hw_rule *rule)
1283 {
1284         struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1285         unsigned int num = 0, den = 0;
1286         int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1287                                   r->nrats, r->rats, &num, &den);
1288         if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1289                 params->rate_num = num;
1290                 params->rate_den = den;
1291         }
1292         return err;
1293 }
1294
1295 /**
1296  * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1297  * @runtime: PCM runtime instance
1298  * @cond: condition bits
1299  * @var: hw_params variable to apply the ratdens constraint
1300  * @r: struct snd_ratdens constriants
1301  */
1302 int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime,
1303                                   unsigned int cond,
1304                                   snd_pcm_hw_param_t var,
1305                                   struct snd_pcm_hw_constraint_ratdens *r)
1306 {
1307         return snd_pcm_hw_rule_add(runtime, cond, var,
1308                                    snd_pcm_hw_rule_ratdens, r,
1309                                    var, -1);
1310 }
1311
1312 EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1313
1314 static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1315                                   struct snd_pcm_hw_rule *rule)
1316 {
1317         unsigned int l = (unsigned long) rule->private;
1318         int width = l & 0xffff;
1319         unsigned int msbits = l >> 16;
1320         struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1321         if (snd_interval_single(i) && snd_interval_value(i) == width)
1322                 params->msbits = msbits;
1323         return 0;
1324 }
1325
1326 /**
1327  * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1328  * @runtime: PCM runtime instance
1329  * @cond: condition bits
1330  * @width: sample bits width
1331  * @msbits: msbits width
1332  */
1333 int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime,
1334                                  unsigned int cond,
1335                                  unsigned int width,
1336                                  unsigned int msbits)
1337 {
1338         unsigned long l = (msbits << 16) | width;
1339         return snd_pcm_hw_rule_add(runtime, cond, -1,
1340                                     snd_pcm_hw_rule_msbits,
1341                                     (void*) l,
1342                                     SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1343 }
1344
1345 EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1346
1347 static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1348                                 struct snd_pcm_hw_rule *rule)
1349 {
1350         unsigned long step = (unsigned long) rule->private;
1351         return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1352 }
1353
1354 /**
1355  * snd_pcm_hw_constraint_step - add a hw constraint step rule
1356  * @runtime: PCM runtime instance
1357  * @cond: condition bits
1358  * @var: hw_params variable to apply the step constraint
1359  * @step: step size
1360  */
1361 int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1362                                unsigned int cond,
1363                                snd_pcm_hw_param_t var,
1364                                unsigned long step)
1365 {
1366         return snd_pcm_hw_rule_add(runtime, cond, var,
1367                                    snd_pcm_hw_rule_step, (void *) step,
1368                                    var, -1);
1369 }
1370
1371 EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1372
1373 static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1374 {
1375         static unsigned int pow2_sizes[] = {
1376                 1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1377                 1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1378                 1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1379                 1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1380         };
1381         return snd_interval_list(hw_param_interval(params, rule->var),
1382                                  ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1383 }
1384
1385 /**
1386  * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1387  * @runtime: PCM runtime instance
1388  * @cond: condition bits
1389  * @var: hw_params variable to apply the power-of-2 constraint
1390  */
1391 int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1392                                unsigned int cond,
1393                                snd_pcm_hw_param_t var)
1394 {
1395         return snd_pcm_hw_rule_add(runtime, cond, var,
1396                                    snd_pcm_hw_rule_pow2, NULL,
1397                                    var, -1);
1398 }
1399
1400 EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1401
1402 static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1403                                   snd_pcm_hw_param_t var)
1404 {
1405         if (hw_is_mask(var)) {
1406                 snd_mask_any(hw_param_mask(params, var));
1407                 params->cmask |= 1 << var;
1408                 params->rmask |= 1 << var;
1409                 return;
1410         }
1411         if (hw_is_interval(var)) {
1412                 snd_interval_any(hw_param_interval(params, var));
1413                 params->cmask |= 1 << var;
1414                 params->rmask |= 1 << var;
1415                 return;
1416         }
1417         snd_BUG();
1418 }
1419
1420 void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1421 {
1422         unsigned int k;
1423         memset(params, 0, sizeof(*params));
1424         for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1425                 _snd_pcm_hw_param_any(params, k);
1426         for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1427                 _snd_pcm_hw_param_any(params, k);
1428         params->info = ~0U;
1429 }
1430
1431 EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1432
1433 /**
1434  * snd_pcm_hw_param_value - return @params field @var value
1435  * @params: the hw_params instance
1436  * @var: parameter to retrieve
1437  * @dir: pointer to the direction (-1,0,1) or %NULL
1438  *
1439  * Return the value for field @var if it's fixed in configuration space
1440  * defined by @params. Return -%EINVAL otherwise.
1441  */
1442 int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1443                            snd_pcm_hw_param_t var, int *dir)
1444 {
1445         if (hw_is_mask(var)) {
1446                 const struct snd_mask *mask = hw_param_mask_c(params, var);
1447                 if (!snd_mask_single(mask))
1448                         return -EINVAL;
1449                 if (dir)
1450                         *dir = 0;
1451                 return snd_mask_value(mask);
1452         }
1453         if (hw_is_interval(var)) {
1454                 const struct snd_interval *i = hw_param_interval_c(params, var);
1455                 if (!snd_interval_single(i))
1456                         return -EINVAL;
1457                 if (dir)
1458                         *dir = i->openmin;
1459                 return snd_interval_value(i);
1460         }
1461         return -EINVAL;
1462 }
1463
1464 EXPORT_SYMBOL(snd_pcm_hw_param_value);
1465
1466 void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1467                                 snd_pcm_hw_param_t var)
1468 {
1469         if (hw_is_mask(var)) {
1470                 snd_mask_none(hw_param_mask(params, var));
1471                 params->cmask |= 1 << var;
1472                 params->rmask |= 1 << var;
1473         } else if (hw_is_interval(var)) {
1474                 snd_interval_none(hw_param_interval(params, var));
1475                 params->cmask |= 1 << var;
1476                 params->rmask |= 1 << var;
1477         } else {
1478                 snd_BUG();
1479         }
1480 }
1481
1482 EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1483
1484 static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1485                                    snd_pcm_hw_param_t var)
1486 {
1487         int changed;
1488         if (hw_is_mask(var))
1489                 changed = snd_mask_refine_first(hw_param_mask(params, var));
1490         else if (hw_is_interval(var))
1491                 changed = snd_interval_refine_first(hw_param_interval(params, var));
1492         else
1493                 return -EINVAL;
1494         if (changed) {
1495                 params->cmask |= 1 << var;
1496                 params->rmask |= 1 << var;
1497         }
1498         return changed;
1499 }
1500
1501
1502 /**
1503  * snd_pcm_hw_param_first - refine config space and return minimum value
1504  * @pcm: PCM instance
1505  * @params: the hw_params instance
1506  * @var: parameter to retrieve
1507  * @dir: pointer to the direction (-1,0,1) or %NULL
1508  *
1509  * Inside configuration space defined by @params remove from @var all
1510  * values > minimum. Reduce configuration space accordingly.
1511  * Return the minimum.
1512  */
1513 int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm,
1514                            struct snd_pcm_hw_params *params,
1515                            snd_pcm_hw_param_t var, int *dir)
1516 {
1517         int changed = _snd_pcm_hw_param_first(params, var);
1518         if (changed < 0)
1519                 return changed;
1520         if (params->rmask) {
1521                 int err = snd_pcm_hw_refine(pcm, params);
1522                 if (snd_BUG_ON(err < 0))
1523                         return err;
1524         }
1525         return snd_pcm_hw_param_value(params, var, dir);
1526 }
1527
1528 EXPORT_SYMBOL(snd_pcm_hw_param_first);
1529
1530 static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1531                                   snd_pcm_hw_param_t var)
1532 {
1533         int changed;
1534         if (hw_is_mask(var))
1535                 changed = snd_mask_refine_last(hw_param_mask(params, var));
1536         else if (hw_is_interval(var))
1537                 changed = snd_interval_refine_last(hw_param_interval(params, var));
1538         else
1539                 return -EINVAL;
1540         if (changed) {
1541                 params->cmask |= 1 << var;
1542                 params->rmask |= 1 << var;
1543         }
1544         return changed;
1545 }
1546
1547
1548 /**
1549  * snd_pcm_hw_param_last - refine config space and return maximum value
1550  * @pcm: PCM instance
1551  * @params: the hw_params instance
1552  * @var: parameter to retrieve
1553  * @dir: pointer to the direction (-1,0,1) or %NULL
1554  *
1555  * Inside configuration space defined by @params remove from @var all
1556  * values < maximum. Reduce configuration space accordingly.
1557  * Return the maximum.
1558  */
1559 int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm,
1560                           struct snd_pcm_hw_params *params,
1561                           snd_pcm_hw_param_t var, int *dir)
1562 {
1563         int changed = _snd_pcm_hw_param_last(params, var);
1564         if (changed < 0)
1565                 return changed;
1566         if (params->rmask) {
1567                 int err = snd_pcm_hw_refine(pcm, params);
1568                 if (snd_BUG_ON(err < 0))
1569                         return err;
1570         }
1571         return snd_pcm_hw_param_value(params, var, dir);
1572 }
1573
1574 EXPORT_SYMBOL(snd_pcm_hw_param_last);
1575
1576 /**
1577  * snd_pcm_hw_param_choose - choose a configuration defined by @params
1578  * @pcm: PCM instance
1579  * @params: the hw_params instance
1580  *
1581  * Choose one configuration from configuration space defined by @params.
1582  * The configuration chosen is that obtained fixing in this order:
1583  * first access, first format, first subformat, min channels,
1584  * min rate, min period time, max buffer size, min tick time
1585  */
1586 int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1587                              struct snd_pcm_hw_params *params)
1588 {
1589         static int vars[] = {
1590                 SNDRV_PCM_HW_PARAM_ACCESS,
1591                 SNDRV_PCM_HW_PARAM_FORMAT,
1592                 SNDRV_PCM_HW_PARAM_SUBFORMAT,
1593                 SNDRV_PCM_HW_PARAM_CHANNELS,
1594                 SNDRV_PCM_HW_PARAM_RATE,
1595                 SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1596                 SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1597                 SNDRV_PCM_HW_PARAM_TICK_TIME,
1598                 -1
1599         };
1600         int err, *v;
1601
1602         for (v = vars; *v != -1; v++) {
1603                 if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1604                         err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1605                 else
1606                         err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1607                 if (snd_BUG_ON(err < 0))
1608                         return err;
1609         }
1610         return 0;
1611 }
1612
1613 static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1614                                    void *arg)
1615 {
1616         struct snd_pcm_runtime *runtime = substream->runtime;
1617         unsigned long flags;
1618         snd_pcm_stream_lock_irqsave(substream, flags);
1619         if (snd_pcm_running(substream) &&
1620             snd_pcm_update_hw_ptr(substream) >= 0)
1621                 runtime->status->hw_ptr %= runtime->buffer_size;
1622         else
1623                 runtime->status->hw_ptr = 0;
1624         snd_pcm_stream_unlock_irqrestore(substream, flags);
1625         return 0;
1626 }
1627
1628 static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1629                                           void *arg)
1630 {
1631         struct snd_pcm_channel_info *info = arg;
1632         struct snd_pcm_runtime *runtime = substream->runtime;
1633         int width;
1634         if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1635                 info->offset = -1;
1636                 return 0;
1637         }
1638         width = snd_pcm_format_physical_width(runtime->format);
1639         if (width < 0)
1640                 return width;
1641         info->offset = 0;
1642         switch (runtime->access) {
1643         case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1644         case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1645                 info->first = info->channel * width;
1646                 info->step = runtime->channels * width;
1647                 break;
1648         case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1649         case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1650         {
1651                 size_t size = runtime->dma_bytes / runtime->channels;
1652                 info->first = info->channel * size * 8;
1653                 info->step = width;
1654                 break;
1655         }
1656         default:
1657                 snd_BUG();
1658                 break;
1659         }
1660         return 0;
1661 }
1662
1663 static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1664                                        void *arg)
1665 {
1666         struct snd_pcm_hw_params *params = arg;
1667         snd_pcm_format_t format;
1668         int channels, width;
1669
1670         params->fifo_size = substream->runtime->hw.fifo_size;
1671         if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1672                 format = params_format(params);
1673                 channels = params_channels(params);
1674                 width = snd_pcm_format_physical_width(format);
1675                 params->fifo_size /= width * channels;
1676         }
1677         return 0;
1678 }
1679
1680 /**
1681  * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1682  * @substream: the pcm substream instance
1683  * @cmd: ioctl command
1684  * @arg: ioctl argument
1685  *
1686  * Processes the generic ioctl commands for PCM.
1687  * Can be passed as the ioctl callback for PCM ops.
1688  *
1689  * Returns zero if successful, or a negative error code on failure.
1690  */
1691 int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1692                       unsigned int cmd, void *arg)
1693 {
1694         switch (cmd) {
1695         case SNDRV_PCM_IOCTL1_INFO:
1696                 return 0;
1697         case SNDRV_PCM_IOCTL1_RESET:
1698                 return snd_pcm_lib_ioctl_reset(substream, arg);
1699         case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1700                 return snd_pcm_lib_ioctl_channel_info(substream, arg);
1701         case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1702                 return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1703         }
1704         return -ENXIO;
1705 }
1706
1707 EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1708
1709 /**
1710  * snd_pcm_period_elapsed - update the pcm status for the next period
1711  * @substream: the pcm substream instance
1712  *
1713  * This function is called from the interrupt handler when the
1714  * PCM has processed the period size.  It will update the current
1715  * pointer, wake up sleepers, etc.
1716  *
1717  * Even if more than one periods have elapsed since the last call, you
1718  * have to call this only once.
1719  */
1720 void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1721 {
1722         struct snd_pcm_runtime *runtime;
1723         unsigned long flags;
1724
1725         if (PCM_RUNTIME_CHECK(substream))
1726                 return;
1727         runtime = substream->runtime;
1728
1729         if (runtime->transfer_ack_begin)
1730                 runtime->transfer_ack_begin(substream);
1731
1732         snd_pcm_stream_lock_irqsave(substream, flags);
1733         if (!snd_pcm_running(substream) ||
1734             snd_pcm_update_hw_ptr0(substream, 1) < 0)
1735                 goto _end;
1736
1737         if (substream->timer_running)
1738                 snd_timer_interrupt(substream->timer, 1);
1739  _end:
1740         snd_pcm_stream_unlock_irqrestore(substream, flags);
1741         if (runtime->transfer_ack_end)
1742                 runtime->transfer_ack_end(substream);
1743         kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1744 }
1745
1746 EXPORT_SYMBOL(snd_pcm_period_elapsed);
1747
1748 /*
1749  * Wait until avail_min data becomes available
1750  * Returns a negative error code if any error occurs during operation.
1751  * The available space is stored on availp.  When err = 0 and avail = 0
1752  * on the capture stream, it indicates the stream is in DRAINING state.
1753  */
1754 static int wait_for_avail(struct snd_pcm_substream *substream,
1755                               snd_pcm_uframes_t *availp)
1756 {
1757         struct snd_pcm_runtime *runtime = substream->runtime;
1758         int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1759         wait_queue_t wait;
1760         int err = 0;
1761         snd_pcm_uframes_t avail = 0;
1762         long wait_time, tout;
1763
1764         init_waitqueue_entry(&wait, current);
1765         set_current_state(TASK_INTERRUPTIBLE);
1766         add_wait_queue(&runtime->tsleep, &wait);
1767
1768         if (runtime->no_period_wakeup)
1769                 wait_time = MAX_SCHEDULE_TIMEOUT;
1770         else {
1771                 wait_time = 10;
1772                 if (runtime->rate) {
1773                         long t = runtime->period_size * 2 / runtime->rate;
1774                         wait_time = max(t, wait_time);
1775                 }
1776                 wait_time = msecs_to_jiffies(wait_time * 1000);
1777         }
1778
1779         for (;;) {
1780                 if (signal_pending(current)) {
1781                         err = -ERESTARTSYS;
1782                         break;
1783                 }
1784
1785                 /*
1786                  * We need to check if space became available already
1787                  * (and thus the wakeup happened already) first to close
1788                  * the race of space already having become available.
1789                  * This check must happen after been added to the waitqueue
1790                  * and having current state be INTERRUPTIBLE.
1791                  */
1792                 if (is_playback)
1793                         avail = snd_pcm_playback_avail(runtime);
1794                 else
1795                         avail = snd_pcm_capture_avail(runtime);
1796                 if (avail >= runtime->twake)
1797                         break;
1798                 snd_pcm_stream_unlock_irq(substream);
1799
1800                 tout = schedule_timeout(wait_time);
1801
1802                 snd_pcm_stream_lock_irq(substream);
1803                 set_current_state(TASK_INTERRUPTIBLE);
1804                 switch (runtime->status->state) {
1805                 case SNDRV_PCM_STATE_SUSPENDED:
1806                         err = -ESTRPIPE;
1807                         goto _endloop;
1808                 case SNDRV_PCM_STATE_XRUN:
1809                         err = -EPIPE;
1810                         goto _endloop;
1811                 case SNDRV_PCM_STATE_DRAINING:
1812                         if (is_playback)
1813                                 err = -EPIPE;
1814                         else
1815                                 avail = 0; /* indicate draining */
1816                         goto _endloop;
1817                 case SNDRV_PCM_STATE_OPEN:
1818                 case SNDRV_PCM_STATE_SETUP:
1819                 case SNDRV_PCM_STATE_DISCONNECTED:
1820                         err = -EBADFD;
1821                         goto _endloop;
1822                 }
1823                 if (!tout) {
1824                         snd_printd("%s write error (DMA or IRQ trouble?)\n",
1825                                    is_playback ? "playback" : "capture");
1826                         err = -EIO;
1827                         break;
1828                 }
1829         }
1830  _endloop:
1831         set_current_state(TASK_RUNNING);
1832         remove_wait_queue(&runtime->tsleep, &wait);
1833         *availp = avail;
1834         return err;
1835 }
1836
1837 static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1838                                       unsigned int hwoff,
1839                                       unsigned long data, unsigned int off,
1840                                       snd_pcm_uframes_t frames)
1841 {
1842         struct snd_pcm_runtime *runtime = substream->runtime;
1843         int err;
1844         char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1845         if (substream->ops->copy) {
1846                 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1847                         return err;
1848         } else {
1849                 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1850                 if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1851                         return -EFAULT;
1852         }
1853         return 0;
1854 }
1855
1856 typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1857                           unsigned long data, unsigned int off,
1858                           snd_pcm_uframes_t size);
1859
1860 static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream,
1861                                             unsigned long data,
1862                                             snd_pcm_uframes_t size,
1863                                             int nonblock,
1864                                             transfer_f transfer)
1865 {
1866         struct snd_pcm_runtime *runtime = substream->runtime;
1867         snd_pcm_uframes_t xfer = 0;
1868         snd_pcm_uframes_t offset = 0;
1869         int err = 0;
1870
1871         if (size == 0)
1872                 return 0;
1873
1874         snd_pcm_stream_lock_irq(substream);
1875         switch (runtime->status->state) {
1876         case SNDRV_PCM_STATE_PREPARED:
1877         case SNDRV_PCM_STATE_RUNNING:
1878         case SNDRV_PCM_STATE_PAUSED:
1879                 break;
1880         case SNDRV_PCM_STATE_XRUN:
1881                 err = -EPIPE;
1882                 goto _end_unlock;
1883         case SNDRV_PCM_STATE_SUSPENDED:
1884                 err = -ESTRPIPE;
1885                 goto _end_unlock;
1886         default:
1887                 err = -EBADFD;
1888                 goto _end_unlock;
1889         }
1890
1891         runtime->twake = runtime->control->avail_min ? : 1;
1892         while (size > 0) {
1893                 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1894                 snd_pcm_uframes_t avail;
1895                 snd_pcm_uframes_t cont;
1896                 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1897                         snd_pcm_update_hw_ptr(substream);
1898                 avail = snd_pcm_playback_avail(runtime);
1899                 if (!avail) {
1900                         if (nonblock) {
1901                                 err = -EAGAIN;
1902                                 goto _end_unlock;
1903                         }
1904                         runtime->twake = min_t(snd_pcm_uframes_t, size,
1905                                         runtime->control->avail_min ? : 1);
1906                         err = wait_for_avail(substream, &avail);
1907                         if (err < 0)
1908                                 goto _end_unlock;
1909                 }
1910                 frames = size > avail ? avail : size;
1911                 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1912                 if (frames > cont)
1913                         frames = cont;
1914                 if (snd_BUG_ON(!frames)) {
1915                         runtime->twake = 0;
1916                         snd_pcm_stream_unlock_irq(substream);
1917                         return -EINVAL;
1918                 }
1919                 appl_ptr = runtime->control->appl_ptr;
1920                 appl_ofs = appl_ptr % runtime->buffer_size;
1921                 snd_pcm_stream_unlock_irq(substream);
1922                 err = transfer(substream, appl_ofs, data, offset, frames);
1923                 snd_pcm_stream_lock_irq(substream);
1924                 if (err < 0)
1925                         goto _end_unlock;
1926                 switch (runtime->status->state) {
1927                 case SNDRV_PCM_STATE_XRUN:
1928                         err = -EPIPE;
1929                         goto _end_unlock;
1930                 case SNDRV_PCM_STATE_SUSPENDED:
1931                         err = -ESTRPIPE;
1932                         goto _end_unlock;
1933                 default:
1934                         break;
1935                 }
1936                 appl_ptr += frames;
1937                 if (appl_ptr >= runtime->boundary)
1938                         appl_ptr -= runtime->boundary;
1939                 runtime->control->appl_ptr = appl_ptr;
1940                 if (substream->ops->ack)
1941                         substream->ops->ack(substream);
1942
1943                 offset += frames;
1944                 size -= frames;
1945                 xfer += frames;
1946                 if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1947                     snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1948                         err = snd_pcm_start(substream);
1949                         if (err < 0)
1950                                 goto _end_unlock;
1951                 }
1952         }
1953  _end_unlock:
1954         runtime->twake = 0;
1955         if (xfer > 0 && err >= 0)
1956                 snd_pcm_update_state(substream, runtime);
1957         snd_pcm_stream_unlock_irq(substream);
1958         return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
1959 }
1960
1961 /* sanity-check for read/write methods */
1962 static int pcm_sanity_check(struct snd_pcm_substream *substream)
1963 {
1964         struct snd_pcm_runtime *runtime;
1965         if (PCM_RUNTIME_CHECK(substream))
1966                 return -ENXIO;
1967         runtime = substream->runtime;
1968         if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
1969                 return -EINVAL;
1970         if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
1971                 return -EBADFD;
1972         return 0;
1973 }
1974
1975 snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
1976 {
1977         struct snd_pcm_runtime *runtime;
1978         int nonblock;
1979         int err;
1980
1981         err = pcm_sanity_check(substream);
1982         if (err < 0)
1983                 return err;
1984         runtime = substream->runtime;
1985         nonblock = !!(substream->f_flags & O_NONBLOCK);
1986
1987         if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
1988             runtime->channels > 1)
1989                 return -EINVAL;
1990         return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
1991                                   snd_pcm_lib_write_transfer);
1992 }
1993
1994 EXPORT_SYMBOL(snd_pcm_lib_write);
1995
1996 static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
1997                                        unsigned int hwoff,
1998                                        unsigned long data, unsigned int off,
1999                                        snd_pcm_uframes_t frames)
2000 {
2001         struct snd_pcm_runtime *runtime = substream->runtime;
2002         int err;
2003         void __user **bufs = (void __user **)data;
2004         int channels = runtime->channels;
2005         int c;
2006         if (substream->ops->copy) {
2007                 if (snd_BUG_ON(!substream->ops->silence))
2008                         return -EINVAL;
2009                 for (c = 0; c < channels; ++c, ++bufs) {
2010                         if (*bufs == NULL) {
2011                                 if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
2012                                         return err;
2013                         } else {
2014                                 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2015                                 if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2016                                         return err;
2017                         }
2018                 }
2019         } else {
2020                 /* default transfer behaviour */
2021                 size_t dma_csize = runtime->dma_bytes / channels;
2022                 for (c = 0; c < channels; ++c, ++bufs) {
2023                         char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2024                         if (*bufs == NULL) {
2025                                 snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
2026                         } else {
2027                                 char __user *buf = *bufs + samples_to_bytes(runtime, off);
2028                                 if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
2029                                         return -EFAULT;
2030                         }
2031                 }
2032         }
2033         return 0;
2034 }
2035
2036 snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
2037                                      void __user **bufs,
2038                                      snd_pcm_uframes_t frames)
2039 {
2040         struct snd_pcm_runtime *runtime;
2041         int nonblock;
2042         int err;
2043
2044         err = pcm_sanity_check(substream);
2045         if (err < 0)
2046                 return err;
2047         runtime = substream->runtime;
2048         nonblock = !!(substream->f_flags & O_NONBLOCK);
2049
2050         if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2051                 return -EINVAL;
2052         return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2053                                   nonblock, snd_pcm_lib_writev_transfer);
2054 }
2055
2056 EXPORT_SYMBOL(snd_pcm_lib_writev);
2057
2058 static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream,
2059                                      unsigned int hwoff,
2060                                      unsigned long data, unsigned int off,
2061                                      snd_pcm_uframes_t frames)
2062 {
2063         struct snd_pcm_runtime *runtime = substream->runtime;
2064         int err;
2065         char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2066         if (substream->ops->copy) {
2067                 if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2068                         return err;
2069         } else {
2070                 char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2071                 if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2072                         return -EFAULT;
2073         }
2074         return 0;
2075 }
2076
2077 static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2078                                            unsigned long data,
2079                                            snd_pcm_uframes_t size,
2080                                            int nonblock,
2081                                            transfer_f transfer)
2082 {
2083         struct snd_pcm_runtime *runtime = substream->runtime;
2084         snd_pcm_uframes_t xfer = 0;
2085         snd_pcm_uframes_t offset = 0;
2086         int err = 0;
2087
2088         if (size == 0)
2089                 return 0;
2090
2091         snd_pcm_stream_lock_irq(substream);
2092         switch (runtime->status->state) {
2093         case SNDRV_PCM_STATE_PREPARED:
2094                 if (size >= runtime->start_threshold) {
2095                         err = snd_pcm_start(substream);
2096                         if (err < 0)
2097                                 goto _end_unlock;
2098                 }
2099                 break;
2100         case SNDRV_PCM_STATE_DRAINING:
2101         case SNDRV_PCM_STATE_RUNNING:
2102         case SNDRV_PCM_STATE_PAUSED:
2103                 break;
2104         case SNDRV_PCM_STATE_XRUN:
2105                 err = -EPIPE;
2106                 goto _end_unlock;
2107         case SNDRV_PCM_STATE_SUSPENDED:
2108                 err = -ESTRPIPE;
2109                 goto _end_unlock;
2110         default:
2111                 err = -EBADFD;
2112                 goto _end_unlock;
2113         }
2114
2115         runtime->twake = runtime->control->avail_min ? : 1;
2116         while (size > 0) {
2117                 snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2118                 snd_pcm_uframes_t avail;
2119                 snd_pcm_uframes_t cont;
2120                 if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2121                         snd_pcm_update_hw_ptr(substream);
2122                 avail = snd_pcm_capture_avail(runtime);
2123                 if (!avail) {
2124                         if (runtime->status->state ==
2125                             SNDRV_PCM_STATE_DRAINING) {
2126                                 snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2127                                 goto _end_unlock;
2128                         }
2129                         if (nonblock) {
2130                                 err = -EAGAIN;
2131                                 goto _end_unlock;
2132                         }
2133                         runtime->twake = min_t(snd_pcm_uframes_t, size,
2134                                         runtime->control->avail_min ? : 1);
2135                         err = wait_for_avail(substream, &avail);
2136                         if (err < 0)
2137                                 goto _end_unlock;
2138                         if (!avail)
2139                                 continue; /* draining */
2140                 }
2141                 frames = size > avail ? avail : size;
2142                 cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2143                 if (frames > cont)
2144                         frames = cont;
2145                 if (snd_BUG_ON(!frames)) {
2146                         runtime->twake = 0;
2147                         snd_pcm_stream_unlock_irq(substream);
2148                         return -EINVAL;
2149                 }
2150                 appl_ptr = runtime->control->appl_ptr;
2151                 appl_ofs = appl_ptr % runtime->buffer_size;
2152                 snd_pcm_stream_unlock_irq(substream);
2153                 err = transfer(substream, appl_ofs, data, offset, frames);
2154                 snd_pcm_stream_lock_irq(substream);
2155                 if (err < 0)
2156                         goto _end_unlock;
2157                 switch (runtime->status->state) {
2158                 case SNDRV_PCM_STATE_XRUN:
2159                         err = -EPIPE;
2160                         goto _end_unlock;
2161                 case SNDRV_PCM_STATE_SUSPENDED:
2162                         err = -ESTRPIPE;
2163                         goto _end_unlock;
2164                 default:
2165                         break;
2166                 }
2167                 appl_ptr += frames;
2168                 if (appl_ptr >= runtime->boundary)
2169                         appl_ptr -= runtime->boundary;
2170                 runtime->control->appl_ptr = appl_ptr;
2171                 if (substream->ops->ack)
2172                         substream->ops->ack(substream);
2173
2174                 offset += frames;
2175                 size -= frames;
2176                 xfer += frames;
2177         }
2178  _end_unlock:
2179         runtime->twake = 0;
2180         if (xfer > 0 && err >= 0)
2181                 snd_pcm_update_state(substream, runtime);
2182         snd_pcm_stream_unlock_irq(substream);
2183         return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2184 }
2185
2186 snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2187 {
2188         struct snd_pcm_runtime *runtime;
2189         int nonblock;
2190         int err;
2191
2192         err = pcm_sanity_check(substream);
2193         if (err < 0)
2194                 return err;
2195         runtime = substream->runtime;
2196         nonblock = !!(substream->f_flags & O_NONBLOCK);
2197         if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2198                 return -EINVAL;
2199         return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2200 }
2201
2202 EXPORT_SYMBOL(snd_pcm_lib_read);
2203
2204 static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2205                                       unsigned int hwoff,
2206                                       unsigned long data, unsigned int off,
2207                                       snd_pcm_uframes_t frames)
2208 {
2209         struct snd_pcm_runtime *runtime = substream->runtime;
2210         int err;
2211         void __user **bufs = (void __user **)data;
2212         int channels = runtime->channels;
2213         int c;
2214         if (substream->ops->copy) {
2215                 for (c = 0; c < channels; ++c, ++bufs) {
2216                         char __user *buf;
2217                         if (*bufs == NULL)
2218                                 continue;
2219                         buf = *bufs + samples_to_bytes(runtime, off);
2220                         if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2221                                 return err;
2222                 }
2223         } else {
2224                 snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2225                 for (c = 0; c < channels; ++c, ++bufs) {
2226                         char *hwbuf;
2227                         char __user *buf;
2228                         if (*bufs == NULL)
2229                                 continue;
2230
2231                         hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2232                         buf = *bufs + samples_to_bytes(runtime, off);
2233                         if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2234                                 return -EFAULT;
2235                 }
2236         }
2237         return 0;
2238 }
2239
2240 snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2241                                     void __user **bufs,
2242                                     snd_pcm_uframes_t frames)
2243 {
2244         struct snd_pcm_runtime *runtime;
2245         int nonblock;
2246         int err;
2247
2248         err = pcm_sanity_check(substream);
2249         if (err < 0)
2250                 return err;
2251         runtime = substream->runtime;
2252         if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2253                 return -EBADFD;
2254
2255         nonblock = !!(substream->f_flags & O_NONBLOCK);
2256         if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2257                 return -EINVAL;
2258         return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2259 }
2260
2261 EXPORT_SYMBOL(snd_pcm_lib_readv);