linux/sound/core/pcm_lib.c
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   1/*
   2 *  Digital Audio (PCM) abstract layer
   3 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   4 *                   Abramo Bagnara <abramo@alsa-project.org>
   5 *
   6 *
   7 *   This program is free software; you can redistribute it and/or modify
   8 *   it under the terms of the GNU General Public License as published by
   9 *   the Free Software Foundation; either version 2 of the License, or
  10 *   (at your option) any later version.
  11 *
  12 *   This program is distributed in the hope that it will be useful,
  13 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 *   GNU General Public License for more details.
  16 *
  17 *   You should have received a copy of the GNU General Public License
  18 *   along with this program; if not, write to the Free Software
  19 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  20 *
  21 */
  22
  23#include <linux/slab.h>
  24#include <linux/time.h>
  25#include <linux/math64.h>
  26#include <linux/export.h>
  27#include <sound/core.h>
  28#include <sound/control.h>
  29#include <sound/info.h>
  30#include <sound/pcm.h>
  31#include <sound/pcm_params.h>
  32#include <sound/timer.h>
  33
  34/*
  35 * fill ring buffer with silence
  36 * runtime->silence_start: starting pointer to silence area
  37 * runtime->silence_filled: size filled with silence
  38 * runtime->silence_threshold: threshold from application
  39 * runtime->silence_size: maximal size from application
  40 *
  41 * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
  42 */
  43void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
  44{
  45        struct snd_pcm_runtime *runtime = substream->runtime;
  46        snd_pcm_uframes_t frames, ofs, transfer;
  47
  48        if (runtime->silence_size < runtime->boundary) {
  49                snd_pcm_sframes_t noise_dist, n;
  50                if (runtime->silence_start != runtime->control->appl_ptr) {
  51                        n = runtime->control->appl_ptr - runtime->silence_start;
  52                        if (n < 0)
  53                                n += runtime->boundary;
  54                        if ((snd_pcm_uframes_t)n < runtime->silence_filled)
  55                                runtime->silence_filled -= n;
  56                        else
  57                                runtime->silence_filled = 0;
  58                        runtime->silence_start = runtime->control->appl_ptr;
  59                }
  60                if (runtime->silence_filled >= runtime->buffer_size)
  61                        return;
  62                noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
  63                if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
  64                        return;
  65                frames = runtime->silence_threshold - noise_dist;
  66                if (frames > runtime->silence_size)
  67                        frames = runtime->silence_size;
  68        } else {
  69                if (new_hw_ptr == ULONG_MAX) {  /* initialization */
  70                        snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
  71                        if (avail > runtime->buffer_size)
  72                                avail = runtime->buffer_size;
  73                        runtime->silence_filled = avail > 0 ? avail : 0;
  74                        runtime->silence_start = (runtime->status->hw_ptr +
  75                                                  runtime->silence_filled) %
  76                                                 runtime->boundary;
  77                } else {
  78                        ofs = runtime->status->hw_ptr;
  79                        frames = new_hw_ptr - ofs;
  80                        if ((snd_pcm_sframes_t)frames < 0)
  81                                frames += runtime->boundary;
  82                        runtime->silence_filled -= frames;
  83                        if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
  84                                runtime->silence_filled = 0;
  85                                runtime->silence_start = new_hw_ptr;
  86                        } else {
  87                                runtime->silence_start = ofs;
  88                        }
  89                }
  90                frames = runtime->buffer_size - runtime->silence_filled;
  91        }
  92        if (snd_BUG_ON(frames > runtime->buffer_size))
  93                return;
  94        if (frames == 0)
  95                return;
  96        ofs = runtime->silence_start % runtime->buffer_size;
  97        while (frames > 0) {
  98                transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
  99                if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
 100                    runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
 101                        if (substream->ops->silence) {
 102                                int err;
 103                                err = substream->ops->silence(substream, -1, ofs, transfer);
 104                                snd_BUG_ON(err < 0);
 105                        } else {
 106                                char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
 107                                snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
 108                        }
 109                } else {
 110                        unsigned int c;
 111                        unsigned int channels = runtime->channels;
 112                        if (substream->ops->silence) {
 113                                for (c = 0; c < channels; ++c) {
 114                                        int err;
 115                                        err = substream->ops->silence(substream, c, ofs, transfer);
 116                                        snd_BUG_ON(err < 0);
 117                                }
 118                        } else {
 119                                size_t dma_csize = runtime->dma_bytes / channels;
 120                                for (c = 0; c < channels; ++c) {
 121                                        char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
 122                                        snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
 123                                }
 124                        }
 125                }
 126                runtime->silence_filled += transfer;
 127                frames -= transfer;
 128                ofs = 0;
 129        }
 130}
 131
 132#ifdef CONFIG_SND_DEBUG
 133void snd_pcm_debug_name(struct snd_pcm_substream *substream,
 134                           char *name, size_t len)
 135{
 136        snprintf(name, len, "pcmC%dD%d%c:%d",
 137                 substream->pcm->card->number,
 138                 substream->pcm->device,
 139                 substream->stream ? 'c' : 'p',
 140                 substream->number);
 141}
 142EXPORT_SYMBOL(snd_pcm_debug_name);
 143#endif
 144
 145#define XRUN_DEBUG_BASIC        (1<<0)
 146#define XRUN_DEBUG_STACK        (1<<1)  /* dump also stack */
 147#define XRUN_DEBUG_JIFFIESCHECK (1<<2)  /* do jiffies check */
 148#define XRUN_DEBUG_PERIODUPDATE (1<<3)  /* full period update info */
 149#define XRUN_DEBUG_HWPTRUPDATE  (1<<4)  /* full hwptr update info */
 150#define XRUN_DEBUG_LOG          (1<<5)  /* show last 10 positions on err */
 151#define XRUN_DEBUG_LOGONCE      (1<<6)  /* do above only once */
 152
 153#ifdef CONFIG_SND_PCM_XRUN_DEBUG
 154
 155#define xrun_debug(substream, mask) \
 156                        ((substream)->pstr->xrun_debug & (mask))
 157#else
 158#define xrun_debug(substream, mask)     0
 159#endif
 160
 161#define dump_stack_on_xrun(substream) do {                      \
 162                if (xrun_debug(substream, XRUN_DEBUG_STACK))    \
 163                        dump_stack();                           \
 164        } while (0)
 165
 166static void xrun(struct snd_pcm_substream *substream)
 167{
 168        struct snd_pcm_runtime *runtime = substream->runtime;
 169
 170        if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
 171                snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 172        snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 173        if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
 174                char name[16];
 175                snd_pcm_debug_name(substream, name, sizeof(name));
 176                snd_printd(KERN_DEBUG "XRUN: %s\n", name);
 177                dump_stack_on_xrun(substream);
 178        }
 179}
 180
 181#ifdef CONFIG_SND_PCM_XRUN_DEBUG
 182#define hw_ptr_error(substream, fmt, args...)                           \
 183        do {                                                            \
 184                if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {          \
 185                        xrun_log_show(substream);                       \
 186                        if (printk_ratelimit()) {                       \
 187                                snd_printd("PCM: " fmt, ##args);        \
 188                        }                                               \
 189                        dump_stack_on_xrun(substream);                  \
 190                }                                                       \
 191        } while (0)
 192
 193#define XRUN_LOG_CNT    10
 194
 195struct hwptr_log_entry {
 196        unsigned int in_interrupt;
 197        unsigned long jiffies;
 198        snd_pcm_uframes_t pos;
 199        snd_pcm_uframes_t period_size;
 200        snd_pcm_uframes_t buffer_size;
 201        snd_pcm_uframes_t old_hw_ptr;
 202        snd_pcm_uframes_t hw_ptr_base;
 203};
 204
 205struct snd_pcm_hwptr_log {
 206        unsigned int idx;
 207        unsigned int hit: 1;
 208        struct hwptr_log_entry entries[XRUN_LOG_CNT];
 209};
 210
 211static void xrun_log(struct snd_pcm_substream *substream,
 212                     snd_pcm_uframes_t pos, int in_interrupt)
 213{
 214        struct snd_pcm_runtime *runtime = substream->runtime;
 215        struct snd_pcm_hwptr_log *log = runtime->hwptr_log;
 216        struct hwptr_log_entry *entry;
 217
 218        if (log == NULL) {
 219                log = kzalloc(sizeof(*log), GFP_ATOMIC);
 220                if (log == NULL)
 221                        return;
 222                runtime->hwptr_log = log;
 223        } else {
 224                if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
 225                        return;
 226        }
 227        entry = &log->entries[log->idx];
 228        entry->in_interrupt = in_interrupt;
 229        entry->jiffies = jiffies;
 230        entry->pos = pos;
 231        entry->period_size = runtime->period_size;
 232        entry->buffer_size = runtime->buffer_size;
 233        entry->old_hw_ptr = runtime->status->hw_ptr;
 234        entry->hw_ptr_base = runtime->hw_ptr_base;
 235        log->idx = (log->idx + 1) % XRUN_LOG_CNT;
 236}
 237
 238static void xrun_log_show(struct snd_pcm_substream *substream)
 239{
 240        struct snd_pcm_hwptr_log *log = substream->runtime->hwptr_log;
 241        struct hwptr_log_entry *entry;
 242        char name[16];
 243        unsigned int idx;
 244        int cnt;
 245
 246        if (log == NULL)
 247                return;
 248        if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
 249                return;
 250        snd_pcm_debug_name(substream, name, sizeof(name));
 251        for (cnt = 0, idx = log->idx; cnt < XRUN_LOG_CNT; cnt++) {
 252                entry = &log->entries[idx];
 253                if (entry->period_size == 0)
 254                        break;
 255                snd_printd("hwptr log: %s: %sj=%lu, pos=%ld/%ld/%ld, "
 256                           "hwptr=%ld/%ld\n",
 257                           name, entry->in_interrupt ? "[Q] " : "",
 258                           entry->jiffies,
 259                           (unsigned long)entry->pos,
 260                           (unsigned long)entry->period_size,
 261                           (unsigned long)entry->buffer_size,
 262                           (unsigned long)entry->old_hw_ptr,
 263                           (unsigned long)entry->hw_ptr_base);
 264                idx++;
 265                idx %= XRUN_LOG_CNT;
 266        }
 267        log->hit = 1;
 268}
 269
 270#else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
 271
 272#define hw_ptr_error(substream, fmt, args...) do { } while (0)
 273#define xrun_log(substream, pos, in_interrupt)  do { } while (0)
 274#define xrun_log_show(substream)        do { } while (0)
 275
 276#endif
 277
 278int snd_pcm_update_state(struct snd_pcm_substream *substream,
 279                         struct snd_pcm_runtime *runtime)
 280{
 281        snd_pcm_uframes_t avail;
 282
 283        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 284                avail = snd_pcm_playback_avail(runtime);
 285        else
 286                avail = snd_pcm_capture_avail(runtime);
 287        if (avail > runtime->avail_max)
 288                runtime->avail_max = avail;
 289        if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
 290                if (avail >= runtime->buffer_size) {
 291                        snd_pcm_drain_done(substream);
 292                        return -EPIPE;
 293                }
 294        } else {
 295                if (avail >= runtime->stop_threshold) {
 296                        xrun(substream);
 297                        return -EPIPE;
 298                }
 299        }
 300        if (runtime->twake) {
 301                if (avail >= runtime->twake)
 302                        wake_up(&runtime->tsleep);
 303        } else if (avail >= runtime->control->avail_min)
 304                wake_up(&runtime->sleep);
 305        return 0;
 306}
 307
 308static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
 309                                  unsigned int in_interrupt)
 310{
 311        struct snd_pcm_runtime *runtime = substream->runtime;
 312        snd_pcm_uframes_t pos;
 313        snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
 314        snd_pcm_sframes_t hdelta, delta;
 315        unsigned long jdelta;
 316        unsigned long curr_jiffies;
 317        struct timespec curr_tstamp;
 318
 319        old_hw_ptr = runtime->status->hw_ptr;
 320
 321        /*
 322         * group pointer, time and jiffies reads to allow for more
 323         * accurate correlations/corrections.
 324         * The values are stored at the end of this routine after
 325         * corrections for hw_ptr position
 326         */
 327        pos = substream->ops->pointer(substream);
 328        curr_jiffies = jiffies;
 329        if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
 330                snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
 331
 332        if (pos == SNDRV_PCM_POS_XRUN) {
 333                xrun(substream);
 334                return -EPIPE;
 335        }
 336        if (pos >= runtime->buffer_size) {
 337                if (printk_ratelimit()) {
 338                        char name[16];
 339                        snd_pcm_debug_name(substream, name, sizeof(name));
 340                        xrun_log_show(substream);
 341                        snd_printd(KERN_ERR  "BUG: %s, pos = %ld, "
 342                                   "buffer size = %ld, period size = %ld\n",
 343                                   name, pos, runtime->buffer_size,
 344                                   runtime->period_size);
 345                }
 346                pos = 0;
 347        }
 348        pos -= pos % runtime->min_align;
 349        if (xrun_debug(substream, XRUN_DEBUG_LOG))
 350                xrun_log(substream, pos, in_interrupt);
 351        hw_base = runtime->hw_ptr_base;
 352        new_hw_ptr = hw_base + pos;
 353        if (in_interrupt) {
 354                /* we know that one period was processed */
 355                /* delta = "expected next hw_ptr" for in_interrupt != 0 */
 356                delta = runtime->hw_ptr_interrupt + runtime->period_size;
 357                if (delta > new_hw_ptr) {
 358                        /* check for double acknowledged interrupts */
 359                        hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 360                        if (hdelta > runtime->hw_ptr_buffer_jiffies/2) {
 361                                hw_base += runtime->buffer_size;
 362                                if (hw_base >= runtime->boundary)
 363                                        hw_base = 0;
 364                                new_hw_ptr = hw_base + pos;
 365                                goto __delta;
 366                        }
 367                }
 368        }
 369        /* new_hw_ptr might be lower than old_hw_ptr in case when */
 370        /* pointer crosses the end of the ring buffer */
 371        if (new_hw_ptr < old_hw_ptr) {
 372                hw_base += runtime->buffer_size;
 373                if (hw_base >= runtime->boundary)
 374                        hw_base = 0;
 375                new_hw_ptr = hw_base + pos;
 376        }
 377      __delta:
 378        delta = new_hw_ptr - old_hw_ptr;
 379        if (delta < 0)
 380                delta += runtime->boundary;
 381        if (xrun_debug(substream, in_interrupt ?
 382                        XRUN_DEBUG_PERIODUPDATE : XRUN_DEBUG_HWPTRUPDATE)) {
 383                char name[16];
 384                snd_pcm_debug_name(substream, name, sizeof(name));
 385                snd_printd("%s_update: %s: pos=%u/%u/%u, "
 386                           "hwptr=%ld/%ld/%ld/%ld\n",
 387                           in_interrupt ? "period" : "hwptr",
 388                           name,
 389                           (unsigned int)pos,
 390                           (unsigned int)runtime->period_size,
 391                           (unsigned int)runtime->buffer_size,
 392                           (unsigned long)delta,
 393                           (unsigned long)old_hw_ptr,
 394                           (unsigned long)new_hw_ptr,
 395                           (unsigned long)runtime->hw_ptr_base);
 396        }
 397
 398        if (runtime->no_period_wakeup) {
 399                snd_pcm_sframes_t xrun_threshold;
 400                /*
 401                 * Without regular period interrupts, we have to check
 402                 * the elapsed time to detect xruns.
 403                 */
 404                jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 405                if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
 406                        goto no_delta_check;
 407                hdelta = jdelta - delta * HZ / runtime->rate;
 408                xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
 409                while (hdelta > xrun_threshold) {
 410                        delta += runtime->buffer_size;
 411                        hw_base += runtime->buffer_size;
 412                        if (hw_base >= runtime->boundary)
 413                                hw_base = 0;
 414                        new_hw_ptr = hw_base + pos;
 415                        hdelta -= runtime->hw_ptr_buffer_jiffies;
 416                }
 417                goto no_delta_check;
 418        }
 419
 420        /* something must be really wrong */
 421        if (delta >= runtime->buffer_size + runtime->period_size) {
 422                hw_ptr_error(substream,
 423                               "Unexpected hw_pointer value %s"
 424                               "(stream=%i, pos=%ld, new_hw_ptr=%ld, "
 425                               "old_hw_ptr=%ld)\n",
 426                                     in_interrupt ? "[Q] " : "[P]",
 427                                     substream->stream, (long)pos,
 428                                     (long)new_hw_ptr, (long)old_hw_ptr);
 429                return 0;
 430        }
 431
 432        /* Do jiffies check only in xrun_debug mode */
 433        if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
 434                goto no_jiffies_check;
 435
 436        /* Skip the jiffies check for hardwares with BATCH flag.
 437         * Such hardware usually just increases the position at each IRQ,
 438         * thus it can't give any strange position.
 439         */
 440        if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
 441                goto no_jiffies_check;
 442        hdelta = delta;
 443        if (hdelta < runtime->delay)
 444                goto no_jiffies_check;
 445        hdelta -= runtime->delay;
 446        jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 447        if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
 448                delta = jdelta /
 449                        (((runtime->period_size * HZ) / runtime->rate)
 450                                                                + HZ/100);
 451                /* move new_hw_ptr according jiffies not pos variable */
 452                new_hw_ptr = old_hw_ptr;
 453                hw_base = delta;
 454                /* use loop to avoid checks for delta overflows */
 455                /* the delta value is small or zero in most cases */
 456                while (delta > 0) {
 457                        new_hw_ptr += runtime->period_size;
 458                        if (new_hw_ptr >= runtime->boundary)
 459                                new_hw_ptr -= runtime->boundary;
 460                        delta--;
 461                }
 462                /* align hw_base to buffer_size */
 463                hw_ptr_error(substream,
 464                             "hw_ptr skipping! %s"
 465                             "(pos=%ld, delta=%ld, period=%ld, "
 466                             "jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
 467                             in_interrupt ? "[Q] " : "",
 468                             (long)pos, (long)hdelta,
 469                             (long)runtime->period_size, jdelta,
 470                             ((hdelta * HZ) / runtime->rate), hw_base,
 471                             (unsigned long)old_hw_ptr,
 472                             (unsigned long)new_hw_ptr);
 473                /* reset values to proper state */
 474                delta = 0;
 475                hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
 476        }
 477 no_jiffies_check:
 478        if (delta > runtime->period_size + runtime->period_size / 2) {
 479                hw_ptr_error(substream,
 480                             "Lost interrupts? %s"
 481                             "(stream=%i, delta=%ld, new_hw_ptr=%ld, "
 482                             "old_hw_ptr=%ld)\n",
 483                             in_interrupt ? "[Q] " : "",
 484                             substream->stream, (long)delta,
 485                             (long)new_hw_ptr,
 486                             (long)old_hw_ptr);
 487        }
 488
 489 no_delta_check:
 490        if (runtime->status->hw_ptr == new_hw_ptr)
 491                return 0;
 492
 493        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 494            runtime->silence_size > 0)
 495                snd_pcm_playback_silence(substream, new_hw_ptr);
 496
 497        if (in_interrupt) {
 498                delta = new_hw_ptr - runtime->hw_ptr_interrupt;
 499                if (delta < 0)
 500                        delta += runtime->boundary;
 501                delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
 502                runtime->hw_ptr_interrupt += delta;
 503                if (runtime->hw_ptr_interrupt >= runtime->boundary)
 504                        runtime->hw_ptr_interrupt -= runtime->boundary;
 505        }
 506        runtime->hw_ptr_base = hw_base;
 507        runtime->status->hw_ptr = new_hw_ptr;
 508        runtime->hw_ptr_jiffies = curr_jiffies;
 509        if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
 510                runtime->status->tstamp = curr_tstamp;
 511
 512        return snd_pcm_update_state(substream, runtime);
 513}
 514
 515/* CAUTION: call it with irq disabled */
 516int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
 517{
 518        return snd_pcm_update_hw_ptr0(substream, 0);
 519}
 520
 521/**
 522 * snd_pcm_set_ops - set the PCM operators
 523 * @pcm: the pcm instance
 524 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
 525 * @ops: the operator table
 526 *
 527 * Sets the given PCM operators to the pcm instance.
 528 */
 529void snd_pcm_set_ops(struct snd_pcm *pcm, int direction, struct snd_pcm_ops *ops)
 530{
 531        struct snd_pcm_str *stream = &pcm->streams[direction];
 532        struct snd_pcm_substream *substream;
 533        
 534        for (substream = stream->substream; substream != NULL; substream = substream->next)
 535                substream->ops = ops;
 536}
 537
 538EXPORT_SYMBOL(snd_pcm_set_ops);
 539
 540/**
 541 * snd_pcm_sync - set the PCM sync id
 542 * @substream: the pcm substream
 543 *
 544 * Sets the PCM sync identifier for the card.
 545 */
 546void snd_pcm_set_sync(struct snd_pcm_substream *substream)
 547{
 548        struct snd_pcm_runtime *runtime = substream->runtime;
 549        
 550        runtime->sync.id32[0] = substream->pcm->card->number;
 551        runtime->sync.id32[1] = -1;
 552        runtime->sync.id32[2] = -1;
 553        runtime->sync.id32[3] = -1;
 554}
 555
 556EXPORT_SYMBOL(snd_pcm_set_sync);
 557
 558/*
 559 *  Standard ioctl routine
 560 */
 561
 562static inline unsigned int div32(unsigned int a, unsigned int b, 
 563                                 unsigned int *r)
 564{
 565        if (b == 0) {
 566                *r = 0;
 567                return UINT_MAX;
 568        }
 569        *r = a % b;
 570        return a / b;
 571}
 572
 573static inline unsigned int div_down(unsigned int a, unsigned int b)
 574{
 575        if (b == 0)
 576                return UINT_MAX;
 577        return a / b;
 578}
 579
 580static inline unsigned int div_up(unsigned int a, unsigned int b)
 581{
 582        unsigned int r;
 583        unsigned int q;
 584        if (b == 0)
 585                return UINT_MAX;
 586        q = div32(a, b, &r);
 587        if (r)
 588                ++q;
 589        return q;
 590}
 591
 592static inline unsigned int mul(unsigned int a, unsigned int b)
 593{
 594        if (a == 0)
 595                return 0;
 596        if (div_down(UINT_MAX, a) < b)
 597                return UINT_MAX;
 598        return a * b;
 599}
 600
 601static inline unsigned int muldiv32(unsigned int a, unsigned int b,
 602                                    unsigned int c, unsigned int *r)
 603{
 604        u_int64_t n = (u_int64_t) a * b;
 605        if (c == 0) {
 606                snd_BUG_ON(!n);
 607                *r = 0;
 608                return UINT_MAX;
 609        }
 610        n = div_u64_rem(n, c, r);
 611        if (n >= UINT_MAX) {
 612                *r = 0;
 613                return UINT_MAX;
 614        }
 615        return n;
 616}
 617
 618/**
 619 * snd_interval_refine - refine the interval value of configurator
 620 * @i: the interval value to refine
 621 * @v: the interval value to refer to
 622 *
 623 * Refines the interval value with the reference value.
 624 * The interval is changed to the range satisfying both intervals.
 625 * The interval status (min, max, integer, etc.) are evaluated.
 626 *
 627 * Returns non-zero if the value is changed, zero if not changed.
 628 */
 629int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
 630{
 631        int changed = 0;
 632        if (snd_BUG_ON(snd_interval_empty(i)))
 633                return -EINVAL;
 634        if (i->min < v->min) {
 635                i->min = v->min;
 636                i->openmin = v->openmin;
 637                changed = 1;
 638        } else if (i->min == v->min && !i->openmin && v->openmin) {
 639                i->openmin = 1;
 640                changed = 1;
 641        }
 642        if (i->max > v->max) {
 643                i->max = v->max;
 644                i->openmax = v->openmax;
 645                changed = 1;
 646        } else if (i->max == v->max && !i->openmax && v->openmax) {
 647                i->openmax = 1;
 648                changed = 1;
 649        }
 650        if (!i->integer && v->integer) {
 651                i->integer = 1;
 652                changed = 1;
 653        }
 654        if (i->integer) {
 655                if (i->openmin) {
 656                        i->min++;
 657                        i->openmin = 0;
 658                }
 659                if (i->openmax) {
 660                        i->max--;
 661                        i->openmax = 0;
 662                }
 663        } else if (!i->openmin && !i->openmax && i->min == i->max)
 664                i->integer = 1;
 665        if (snd_interval_checkempty(i)) {
 666                snd_interval_none(i);
 667                return -EINVAL;
 668        }
 669        return changed;
 670}
 671
 672EXPORT_SYMBOL(snd_interval_refine);
 673
 674static int snd_interval_refine_first(struct snd_interval *i)
 675{
 676        if (snd_BUG_ON(snd_interval_empty(i)))
 677                return -EINVAL;
 678        if (snd_interval_single(i))
 679                return 0;
 680        i->max = i->min;
 681        i->openmax = i->openmin;
 682        if (i->openmax)
 683                i->max++;
 684        return 1;
 685}
 686
 687static int snd_interval_refine_last(struct snd_interval *i)
 688{
 689        if (snd_BUG_ON(snd_interval_empty(i)))
 690                return -EINVAL;
 691        if (snd_interval_single(i))
 692                return 0;
 693        i->min = i->max;
 694        i->openmin = i->openmax;
 695        if (i->openmin)
 696                i->min--;
 697        return 1;
 698}
 699
 700void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 701{
 702        if (a->empty || b->empty) {
 703                snd_interval_none(c);
 704                return;
 705        }
 706        c->empty = 0;
 707        c->min = mul(a->min, b->min);
 708        c->openmin = (a->openmin || b->openmin);
 709        c->max = mul(a->max,  b->max);
 710        c->openmax = (a->openmax || b->openmax);
 711        c->integer = (a->integer && b->integer);
 712}
 713
 714/**
 715 * snd_interval_div - refine the interval value with division
 716 * @a: dividend
 717 * @b: divisor
 718 * @c: quotient
 719 *
 720 * c = a / b
 721 *
 722 * Returns non-zero if the value is changed, zero if not changed.
 723 */
 724void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 725{
 726        unsigned int r;
 727        if (a->empty || b->empty) {
 728                snd_interval_none(c);
 729                return;
 730        }
 731        c->empty = 0;
 732        c->min = div32(a->min, b->max, &r);
 733        c->openmin = (r || a->openmin || b->openmax);
 734        if (b->min > 0) {
 735                c->max = div32(a->max, b->min, &r);
 736                if (r) {
 737                        c->max++;
 738                        c->openmax = 1;
 739                } else
 740                        c->openmax = (a->openmax || b->openmin);
 741        } else {
 742                c->max = UINT_MAX;
 743                c->openmax = 0;
 744        }
 745        c->integer = 0;
 746}
 747
 748/**
 749 * snd_interval_muldivk - refine the interval value
 750 * @a: dividend 1
 751 * @b: dividend 2
 752 * @k: divisor (as integer)
 753 * @c: result
 754  *
 755 * c = a * b / k
 756 *
 757 * Returns non-zero if the value is changed, zero if not changed.
 758 */
 759void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
 760                      unsigned int k, struct snd_interval *c)
 761{
 762        unsigned int r;
 763        if (a->empty || b->empty) {
 764                snd_interval_none(c);
 765                return;
 766        }
 767        c->empty = 0;
 768        c->min = muldiv32(a->min, b->min, k, &r);
 769        c->openmin = (r || a->openmin || b->openmin);
 770        c->max = muldiv32(a->max, b->max, k, &r);
 771        if (r) {
 772                c->max++;
 773                c->openmax = 1;
 774        } else
 775                c->openmax = (a->openmax || b->openmax);
 776        c->integer = 0;
 777}
 778
 779/**
 780 * snd_interval_mulkdiv - refine the interval value
 781 * @a: dividend 1
 782 * @k: dividend 2 (as integer)
 783 * @b: divisor
 784 * @c: result
 785 *
 786 * c = a * k / b
 787 *
 788 * Returns non-zero if the value is changed, zero if not changed.
 789 */
 790void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
 791                      const struct snd_interval *b, struct snd_interval *c)
 792{
 793        unsigned int r;
 794        if (a->empty || b->empty) {
 795                snd_interval_none(c);
 796                return;
 797        }
 798        c->empty = 0;
 799        c->min = muldiv32(a->min, k, b->max, &r);
 800        c->openmin = (r || a->openmin || b->openmax);
 801        if (b->min > 0) {
 802                c->max = muldiv32(a->max, k, b->min, &r);
 803                if (r) {
 804                        c->max++;
 805                        c->openmax = 1;
 806                } else
 807                        c->openmax = (a->openmax || b->openmin);
 808        } else {
 809                c->max = UINT_MAX;
 810                c->openmax = 0;
 811        }
 812        c->integer = 0;
 813}
 814
 815/* ---- */
 816
 817
 818/**
 819 * snd_interval_ratnum - refine the interval value
 820 * @i: interval to refine
 821 * @rats_count: number of ratnum_t 
 822 * @rats: ratnum_t array
 823 * @nump: pointer to store the resultant numerator
 824 * @denp: pointer to store the resultant denominator
 825 *
 826 * Returns non-zero if the value is changed, zero if not changed.
 827 */
 828int snd_interval_ratnum(struct snd_interval *i,
 829                        unsigned int rats_count, struct snd_ratnum *rats,
 830                        unsigned int *nump, unsigned int *denp)
 831{
 832        unsigned int best_num, best_den;
 833        int best_diff;
 834        unsigned int k;
 835        struct snd_interval t;
 836        int err;
 837        unsigned int result_num, result_den;
 838        int result_diff;
 839
 840        best_num = best_den = best_diff = 0;
 841        for (k = 0; k < rats_count; ++k) {
 842                unsigned int num = rats[k].num;
 843                unsigned int den;
 844                unsigned int q = i->min;
 845                int diff;
 846                if (q == 0)
 847                        q = 1;
 848                den = div_up(num, q);
 849                if (den < rats[k].den_min)
 850                        continue;
 851                if (den > rats[k].den_max)
 852                        den = rats[k].den_max;
 853                else {
 854                        unsigned int r;
 855                        r = (den - rats[k].den_min) % rats[k].den_step;
 856                        if (r != 0)
 857                                den -= r;
 858                }
 859                diff = num - q * den;
 860                if (diff < 0)
 861                        diff = -diff;
 862                if (best_num == 0 ||
 863                    diff * best_den < best_diff * den) {
 864                        best_diff = diff;
 865                        best_den = den;
 866                        best_num = num;
 867                }
 868        }
 869        if (best_den == 0) {
 870                i->empty = 1;
 871                return -EINVAL;
 872        }
 873        t.min = div_down(best_num, best_den);
 874        t.openmin = !!(best_num % best_den);
 875        
 876        result_num = best_num;
 877        result_diff = best_diff;
 878        result_den = best_den;
 879        best_num = best_den = best_diff = 0;
 880        for (k = 0; k < rats_count; ++k) {
 881                unsigned int num = rats[k].num;
 882                unsigned int den;
 883                unsigned int q = i->max;
 884                int diff;
 885                if (q == 0) {
 886                        i->empty = 1;
 887                        return -EINVAL;
 888                }
 889                den = div_down(num, q);
 890                if (den > rats[k].den_max)
 891                        continue;
 892                if (den < rats[k].den_min)
 893                        den = rats[k].den_min;
 894                else {
 895                        unsigned int r;
 896                        r = (den - rats[k].den_min) % rats[k].den_step;
 897                        if (r != 0)
 898                                den += rats[k].den_step - r;
 899                }
 900                diff = q * den - num;
 901                if (diff < 0)
 902                        diff = -diff;
 903                if (best_num == 0 ||
 904                    diff * best_den < best_diff * den) {
 905                        best_diff = diff;
 906                        best_den = den;
 907                        best_num = num;
 908                }
 909        }
 910        if (best_den == 0) {
 911                i->empty = 1;
 912                return -EINVAL;
 913        }
 914        t.max = div_up(best_num, best_den);
 915        t.openmax = !!(best_num % best_den);
 916        t.integer = 0;
 917        err = snd_interval_refine(i, &t);
 918        if (err < 0)
 919                return err;
 920
 921        if (snd_interval_single(i)) {
 922                if (best_diff * result_den < result_diff * best_den) {
 923                        result_num = best_num;
 924                        result_den = best_den;
 925                }
 926                if (nump)
 927                        *nump = result_num;
 928                if (denp)
 929                        *denp = result_den;
 930        }
 931        return err;
 932}
 933
 934EXPORT_SYMBOL(snd_interval_ratnum);
 935
 936/**
 937 * snd_interval_ratden - refine the interval value
 938 * @i: interval to refine
 939 * @rats_count: number of struct ratden
 940 * @rats: struct ratden array
 941 * @nump: pointer to store the resultant numerator
 942 * @denp: pointer to store the resultant denominator
 943 *
 944 * Returns non-zero if the value is changed, zero if not changed.
 945 */
 946static int snd_interval_ratden(struct snd_interval *i,
 947                               unsigned int rats_count, struct snd_ratden *rats,
 948                               unsigned int *nump, unsigned int *denp)
 949{
 950        unsigned int best_num, best_diff, best_den;
 951        unsigned int k;
 952        struct snd_interval t;
 953        int err;
 954
 955        best_num = best_den = best_diff = 0;
 956        for (k = 0; k < rats_count; ++k) {
 957                unsigned int num;
 958                unsigned int den = rats[k].den;
 959                unsigned int q = i->min;
 960                int diff;
 961                num = mul(q, den);
 962                if (num > rats[k].num_max)
 963                        continue;
 964                if (num < rats[k].num_min)
 965                        num = rats[k].num_max;
 966                else {
 967                        unsigned int r;
 968                        r = (num - rats[k].num_min) % rats[k].num_step;
 969                        if (r != 0)
 970                                num += rats[k].num_step - r;
 971                }
 972                diff = num - q * den;
 973                if (best_num == 0 ||
 974                    diff * best_den < best_diff * den) {
 975                        best_diff = diff;
 976                        best_den = den;
 977                        best_num = num;
 978                }
 979        }
 980        if (best_den == 0) {
 981                i->empty = 1;
 982                return -EINVAL;
 983        }
 984        t.min = div_down(best_num, best_den);
 985        t.openmin = !!(best_num % best_den);
 986        
 987        best_num = best_den = best_diff = 0;
 988        for (k = 0; k < rats_count; ++k) {
 989                unsigned int num;
 990                unsigned int den = rats[k].den;
 991                unsigned int q = i->max;
 992                int diff;
 993                num = mul(q, den);
 994                if (num < rats[k].num_min)
 995                        continue;
 996                if (num > rats[k].num_max)
 997                        num = rats[k].num_max;
 998                else {
 999                        unsigned int r;
1000                        r = (num - rats[k].num_min) % rats[k].num_step;
1001                        if (r != 0)
1002                                num -= r;
1003                }
1004                diff = q * den - num;
1005                if (best_num == 0 ||
1006                    diff * best_den < best_diff * den) {
1007                        best_diff = diff;
1008                        best_den = den;
1009                        best_num = num;
1010                }
1011        }
1012        if (best_den == 0) {
1013                i->empty = 1;
1014                return -EINVAL;
1015        }
1016        t.max = div_up(best_num, best_den);
1017        t.openmax = !!(best_num % best_den);
1018        t.integer = 0;
1019        err = snd_interval_refine(i, &t);
1020        if (err < 0)
1021                return err;
1022
1023        if (snd_interval_single(i)) {
1024                if (nump)
1025                        *nump = best_num;
1026                if (denp)
1027                        *denp = best_den;
1028        }
1029        return err;
1030}
1031
1032/**
1033 * snd_interval_list - refine the interval value from the list
1034 * @i: the interval value to refine
1035 * @count: the number of elements in the list
1036 * @list: the value list
1037 * @mask: the bit-mask to evaluate
1038 *
1039 * Refines the interval value from the list.
1040 * When mask is non-zero, only the elements corresponding to bit 1 are
1041 * evaluated.
1042 *
1043 * Returns non-zero if the value is changed, zero if not changed.
1044 */
1045int snd_interval_list(struct snd_interval *i, unsigned int count,
1046                      const unsigned int *list, unsigned int mask)
1047{
1048        unsigned int k;
1049        struct snd_interval list_range;
1050
1051        if (!count) {
1052                i->empty = 1;
1053                return -EINVAL;
1054        }
1055        snd_interval_any(&list_range);
1056        list_range.min = UINT_MAX;
1057        list_range.max = 0;
1058        for (k = 0; k < count; k++) {
1059                if (mask && !(mask & (1 << k)))
1060                        continue;
1061                if (!snd_interval_test(i, list[k]))
1062                        continue;
1063                list_range.min = min(list_range.min, list[k]);
1064                list_range.max = max(list_range.max, list[k]);
1065        }
1066        return snd_interval_refine(i, &list_range);
1067}
1068
1069EXPORT_SYMBOL(snd_interval_list);
1070
1071static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
1072{
1073        unsigned int n;
1074        int changed = 0;
1075        n = (i->min - min) % step;
1076        if (n != 0 || i->openmin) {
1077                i->min += step - n;
1078                changed = 1;
1079        }
1080        n = (i->max - min) % step;
1081        if (n != 0 || i->openmax) {
1082                i->max -= n;
1083                changed = 1;
1084        }
1085        if (snd_interval_checkempty(i)) {
1086                i->empty = 1;
1087                return -EINVAL;
1088        }
1089        return changed;
1090}
1091
1092/* Info constraints helpers */
1093
1094/**
1095 * snd_pcm_hw_rule_add - add the hw-constraint rule
1096 * @runtime: the pcm runtime instance
1097 * @cond: condition bits
1098 * @var: the variable to evaluate
1099 * @func: the evaluation function
1100 * @private: the private data pointer passed to function
1101 * @dep: the dependent variables
1102 *
1103 * Returns zero if successful, or a negative error code on failure.
1104 */
1105int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1106                        int var,
1107                        snd_pcm_hw_rule_func_t func, void *private,
1108                        int dep, ...)
1109{
1110        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1111        struct snd_pcm_hw_rule *c;
1112        unsigned int k;
1113        va_list args;
1114        va_start(args, dep);
1115        if (constrs->rules_num >= constrs->rules_all) {
1116                struct snd_pcm_hw_rule *new;
1117                unsigned int new_rules = constrs->rules_all + 16;
1118                new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1119                if (!new) {
1120                        va_end(args);
1121                        return -ENOMEM;
1122                }
1123                if (constrs->rules) {
1124                        memcpy(new, constrs->rules,
1125                               constrs->rules_num * sizeof(*c));
1126                        kfree(constrs->rules);
1127                }
1128                constrs->rules = new;
1129                constrs->rules_all = new_rules;
1130        }
1131        c = &constrs->rules[constrs->rules_num];
1132        c->cond = cond;
1133        c->func = func;
1134        c->var = var;
1135        c->private = private;
1136        k = 0;
1137        while (1) {
1138                if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1139                        va_end(args);
1140                        return -EINVAL;
1141                }
1142                c->deps[k++] = dep;
1143                if (dep < 0)
1144                        break;
1145                dep = va_arg(args, int);
1146        }
1147        constrs->rules_num++;
1148        va_end(args);
1149        return 0;
1150}
1151
1152EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1153
1154/**
1155 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1156 * @runtime: PCM runtime instance
1157 * @var: hw_params variable to apply the mask
1158 * @mask: the bitmap mask
1159 *
1160 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1161 */
1162int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1163                               u_int32_t mask)
1164{
1165        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1166        struct snd_mask *maskp = constrs_mask(constrs, var);
1167        *maskp->bits &= mask;
1168        memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1169        if (*maskp->bits == 0)
1170                return -EINVAL;
1171        return 0;
1172}
1173
1174/**
1175 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1176 * @runtime: PCM runtime instance
1177 * @var: hw_params variable to apply the mask
1178 * @mask: the 64bit bitmap mask
1179 *
1180 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1181 */
1182int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1183                                 u_int64_t mask)
1184{
1185        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1186        struct snd_mask *maskp = constrs_mask(constrs, var);
1187        maskp->bits[0] &= (u_int32_t)mask;
1188        maskp->bits[1] &= (u_int32_t)(mask >> 32);
1189        memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1190        if (! maskp->bits[0] && ! maskp->bits[1])
1191                return -EINVAL;
1192        return 0;
1193}
1194
1195/**
1196 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1197 * @runtime: PCM runtime instance
1198 * @var: hw_params variable to apply the integer constraint
1199 *
1200 * Apply the constraint of integer to an interval parameter.
1201 */
1202int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1203{
1204        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1205        return snd_interval_setinteger(constrs_interval(constrs, var));
1206}
1207
1208EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1209
1210/**
1211 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1212 * @runtime: PCM runtime instance
1213 * @var: hw_params variable to apply the range
1214 * @min: the minimal value
1215 * @max: the maximal value
1216 * 
1217 * Apply the min/max range constraint to an interval parameter.
1218 */
1219int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1220                                 unsigned int min, unsigned int max)
1221{
1222        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1223        struct snd_interval t;
1224        t.min = min;
1225        t.max = max;
1226        t.openmin = t.openmax = 0;
1227        t.integer = 0;
1228        return snd_interval_refine(constrs_interval(constrs, var), &t);
1229}
1230
1231EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1232
1233static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1234                                struct snd_pcm_hw_rule *rule)
1235{
1236        struct snd_pcm_hw_constraint_list *list = rule->private;
1237        return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1238}               
1239
1240
1241/**
1242 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1243 * @runtime: PCM runtime instance
1244 * @cond: condition bits
1245 * @var: hw_params variable to apply the list constraint
1246 * @l: list
1247 * 
1248 * Apply the list of constraints to an interval parameter.
1249 */
1250int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1251                               unsigned int cond,
1252                               snd_pcm_hw_param_t var,
1253                               const struct snd_pcm_hw_constraint_list *l)
1254{
1255        return snd_pcm_hw_rule_add(runtime, cond, var,
1256                                   snd_pcm_hw_rule_list, (void *)l,
1257                                   var, -1);
1258}
1259
1260EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1261
1262static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1263                                   struct snd_pcm_hw_rule *rule)
1264{
1265        struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1266        unsigned int num = 0, den = 0;
1267        int err;
1268        err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1269                                  r->nrats, r->rats, &num, &den);
1270        if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1271                params->rate_num = num;
1272                params->rate_den = den;
1273        }
1274        return err;
1275}
1276
1277/**
1278 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1279 * @runtime: PCM runtime instance
1280 * @cond: condition bits
1281 * @var: hw_params variable to apply the ratnums constraint
1282 * @r: struct snd_ratnums constriants
1283 */
1284int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime, 
1285                                  unsigned int cond,
1286                                  snd_pcm_hw_param_t var,
1287                                  struct snd_pcm_hw_constraint_ratnums *r)
1288{
1289        return snd_pcm_hw_rule_add(runtime, cond, var,
1290                                   snd_pcm_hw_rule_ratnums, r,
1291                                   var, -1);
1292}
1293
1294EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1295
1296static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1297                                   struct snd_pcm_hw_rule *rule)
1298{
1299        struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1300        unsigned int num = 0, den = 0;
1301        int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1302                                  r->nrats, r->rats, &num, &den);
1303        if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1304                params->rate_num = num;
1305                params->rate_den = den;
1306        }
1307        return err;
1308}
1309
1310/**
1311 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1312 * @runtime: PCM runtime instance
1313 * @cond: condition bits
1314 * @var: hw_params variable to apply the ratdens constraint
1315 * @r: struct snd_ratdens constriants
1316 */
1317int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime, 
1318                                  unsigned int cond,
1319                                  snd_pcm_hw_param_t var,
1320                                  struct snd_pcm_hw_constraint_ratdens *r)
1321{
1322        return snd_pcm_hw_rule_add(runtime, cond, var,
1323                                   snd_pcm_hw_rule_ratdens, r,
1324                                   var, -1);
1325}
1326
1327EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1328
1329static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1330                                  struct snd_pcm_hw_rule *rule)
1331{
1332        unsigned int l = (unsigned long) rule->private;
1333        int width = l & 0xffff;
1334        unsigned int msbits = l >> 16;
1335        struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1336        if (snd_interval_single(i) && snd_interval_value(i) == width)
1337                params->msbits = msbits;
1338        return 0;
1339}
1340
1341/**
1342 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1343 * @runtime: PCM runtime instance
1344 * @cond: condition bits
1345 * @width: sample bits width
1346 * @msbits: msbits width
1347 */
1348int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime, 
1349                                 unsigned int cond,
1350                                 unsigned int width,
1351                                 unsigned int msbits)
1352{
1353        unsigned long l = (msbits << 16) | width;
1354        return snd_pcm_hw_rule_add(runtime, cond, -1,
1355                                    snd_pcm_hw_rule_msbits,
1356                                    (void*) l,
1357                                    SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1358}
1359
1360EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1361
1362static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1363                                struct snd_pcm_hw_rule *rule)
1364{
1365        unsigned long step = (unsigned long) rule->private;
1366        return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1367}
1368
1369/**
1370 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1371 * @runtime: PCM runtime instance
1372 * @cond: condition bits
1373 * @var: hw_params variable to apply the step constraint
1374 * @step: step size
1375 */
1376int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1377                               unsigned int cond,
1378                               snd_pcm_hw_param_t var,
1379                               unsigned long step)
1380{
1381        return snd_pcm_hw_rule_add(runtime, cond, var, 
1382                                   snd_pcm_hw_rule_step, (void *) step,
1383                                   var, -1);
1384}
1385
1386EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1387
1388static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1389{
1390        static unsigned int pow2_sizes[] = {
1391                1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1392                1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1393                1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1394                1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1395        };
1396        return snd_interval_list(hw_param_interval(params, rule->var),
1397                                 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1398}               
1399
1400/**
1401 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1402 * @runtime: PCM runtime instance
1403 * @cond: condition bits
1404 * @var: hw_params variable to apply the power-of-2 constraint
1405 */
1406int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1407                               unsigned int cond,
1408                               snd_pcm_hw_param_t var)
1409{
1410        return snd_pcm_hw_rule_add(runtime, cond, var, 
1411                                   snd_pcm_hw_rule_pow2, NULL,
1412                                   var, -1);
1413}
1414
1415EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1416
1417static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1418                                           struct snd_pcm_hw_rule *rule)
1419{
1420        unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1421        struct snd_interval *rate;
1422
1423        rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1424        return snd_interval_list(rate, 1, &base_rate, 0);
1425}
1426
1427/**
1428 * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1429 * @runtime: PCM runtime instance
1430 * @base_rate: the rate at which the hardware does not resample
1431 */
1432int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1433                               unsigned int base_rate)
1434{
1435        return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1436                                   SNDRV_PCM_HW_PARAM_RATE,
1437                                   snd_pcm_hw_rule_noresample_func,
1438                                   (void *)(uintptr_t)base_rate,
1439                                   SNDRV_PCM_HW_PARAM_RATE, -1);
1440}
1441EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1442
1443static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1444                                  snd_pcm_hw_param_t var)
1445{
1446        if (hw_is_mask(var)) {
1447                snd_mask_any(hw_param_mask(params, var));
1448                params->cmask |= 1 << var;
1449                params->rmask |= 1 << var;
1450                return;
1451        }
1452        if (hw_is_interval(var)) {
1453                snd_interval_any(hw_param_interval(params, var));
1454                params->cmask |= 1 << var;
1455                params->rmask |= 1 << var;
1456                return;
1457        }
1458        snd_BUG();
1459}
1460
1461void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1462{
1463        unsigned int k;
1464        memset(params, 0, sizeof(*params));
1465        for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1466                _snd_pcm_hw_param_any(params, k);
1467        for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1468                _snd_pcm_hw_param_any(params, k);
1469        params->info = ~0U;
1470}
1471
1472EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1473
1474/**
1475 * snd_pcm_hw_param_value - return @params field @var value
1476 * @params: the hw_params instance
1477 * @var: parameter to retrieve
1478 * @dir: pointer to the direction (-1,0,1) or %NULL
1479 *
1480 * Return the value for field @var if it's fixed in configuration space
1481 * defined by @params. Return -%EINVAL otherwise.
1482 */
1483int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1484                           snd_pcm_hw_param_t var, int *dir)
1485{
1486        if (hw_is_mask(var)) {
1487                const struct snd_mask *mask = hw_param_mask_c(params, var);
1488                if (!snd_mask_single(mask))
1489                        return -EINVAL;
1490                if (dir)
1491                        *dir = 0;
1492                return snd_mask_value(mask);
1493        }
1494        if (hw_is_interval(var)) {
1495                const struct snd_interval *i = hw_param_interval_c(params, var);
1496                if (!snd_interval_single(i))
1497                        return -EINVAL;
1498                if (dir)
1499                        *dir = i->openmin;
1500                return snd_interval_value(i);
1501        }
1502        return -EINVAL;
1503}
1504
1505EXPORT_SYMBOL(snd_pcm_hw_param_value);
1506
1507void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1508                                snd_pcm_hw_param_t var)
1509{
1510        if (hw_is_mask(var)) {
1511                snd_mask_none(hw_param_mask(params, var));
1512                params->cmask |= 1 << var;
1513                params->rmask |= 1 << var;
1514        } else if (hw_is_interval(var)) {
1515                snd_interval_none(hw_param_interval(params, var));
1516                params->cmask |= 1 << var;
1517                params->rmask |= 1 << var;
1518        } else {
1519                snd_BUG();
1520        }
1521}
1522
1523EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1524
1525static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1526                                   snd_pcm_hw_param_t var)
1527{
1528        int changed;
1529        if (hw_is_mask(var))
1530                changed = snd_mask_refine_first(hw_param_mask(params, var));
1531        else if (hw_is_interval(var))
1532                changed = snd_interval_refine_first(hw_param_interval(params, var));
1533        else
1534                return -EINVAL;
1535        if (changed) {
1536                params->cmask |= 1 << var;
1537                params->rmask |= 1 << var;
1538        }
1539        return changed;
1540}
1541
1542
1543/**
1544 * snd_pcm_hw_param_first - refine config space and return minimum value
1545 * @pcm: PCM instance
1546 * @params: the hw_params instance
1547 * @var: parameter to retrieve
1548 * @dir: pointer to the direction (-1,0,1) or %NULL
1549 *
1550 * Inside configuration space defined by @params remove from @var all
1551 * values > minimum. Reduce configuration space accordingly.
1552 * Return the minimum.
1553 */
1554int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm, 
1555                           struct snd_pcm_hw_params *params, 
1556                           snd_pcm_hw_param_t var, int *dir)
1557{
1558        int changed = _snd_pcm_hw_param_first(params, var);
1559        if (changed < 0)
1560                return changed;
1561        if (params->rmask) {
1562                int err = snd_pcm_hw_refine(pcm, params);
1563                if (snd_BUG_ON(err < 0))
1564                        return err;
1565        }
1566        return snd_pcm_hw_param_value(params, var, dir);
1567}
1568
1569EXPORT_SYMBOL(snd_pcm_hw_param_first);
1570
1571static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1572                                  snd_pcm_hw_param_t var)
1573{
1574        int changed;
1575        if (hw_is_mask(var))
1576                changed = snd_mask_refine_last(hw_param_mask(params, var));
1577        else if (hw_is_interval(var))
1578                changed = snd_interval_refine_last(hw_param_interval(params, var));
1579        else
1580                return -EINVAL;
1581        if (changed) {
1582                params->cmask |= 1 << var;
1583                params->rmask |= 1 << var;
1584        }
1585        return changed;
1586}
1587
1588
1589/**
1590 * snd_pcm_hw_param_last - refine config space and return maximum value
1591 * @pcm: PCM instance
1592 * @params: the hw_params instance
1593 * @var: parameter to retrieve
1594 * @dir: pointer to the direction (-1,0,1) or %NULL
1595 *
1596 * Inside configuration space defined by @params remove from @var all
1597 * values < maximum. Reduce configuration space accordingly.
1598 * Return the maximum.
1599 */
1600int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm, 
1601                          struct snd_pcm_hw_params *params,
1602                          snd_pcm_hw_param_t var, int *dir)
1603{
1604        int changed = _snd_pcm_hw_param_last(params, var);
1605        if (changed < 0)
1606                return changed;
1607        if (params->rmask) {
1608                int err = snd_pcm_hw_refine(pcm, params);
1609                if (snd_BUG_ON(err < 0))
1610                        return err;
1611        }
1612        return snd_pcm_hw_param_value(params, var, dir);
1613}
1614
1615EXPORT_SYMBOL(snd_pcm_hw_param_last);
1616
1617/**
1618 * snd_pcm_hw_param_choose - choose a configuration defined by @params
1619 * @pcm: PCM instance
1620 * @params: the hw_params instance
1621 *
1622 * Choose one configuration from configuration space defined by @params.
1623 * The configuration chosen is that obtained fixing in this order:
1624 * first access, first format, first subformat, min channels,
1625 * min rate, min period time, max buffer size, min tick time
1626 */
1627int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1628                             struct snd_pcm_hw_params *params)
1629{
1630        static int vars[] = {
1631                SNDRV_PCM_HW_PARAM_ACCESS,
1632                SNDRV_PCM_HW_PARAM_FORMAT,
1633                SNDRV_PCM_HW_PARAM_SUBFORMAT,
1634                SNDRV_PCM_HW_PARAM_CHANNELS,
1635                SNDRV_PCM_HW_PARAM_RATE,
1636                SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1637                SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1638                SNDRV_PCM_HW_PARAM_TICK_TIME,
1639                -1
1640        };
1641        int err, *v;
1642
1643        for (v = vars; *v != -1; v++) {
1644                if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1645                        err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1646                else
1647                        err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1648                if (snd_BUG_ON(err < 0))
1649                        return err;
1650        }
1651        return 0;
1652}
1653
1654static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1655                                   void *arg)
1656{
1657        struct snd_pcm_runtime *runtime = substream->runtime;
1658        unsigned long flags;
1659        snd_pcm_stream_lock_irqsave(substream, flags);
1660        if (snd_pcm_running(substream) &&
1661            snd_pcm_update_hw_ptr(substream) >= 0)
1662                runtime->status->hw_ptr %= runtime->buffer_size;
1663        else
1664                runtime->status->hw_ptr = 0;
1665        snd_pcm_stream_unlock_irqrestore(substream, flags);
1666        return 0;
1667}
1668
1669static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1670                                          void *arg)
1671{
1672        struct snd_pcm_channel_info *info = arg;
1673        struct snd_pcm_runtime *runtime = substream->runtime;
1674        int width;
1675        if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1676                info->offset = -1;
1677                return 0;
1678        }
1679        width = snd_pcm_format_physical_width(runtime->format);
1680        if (width < 0)
1681                return width;
1682        info->offset = 0;
1683        switch (runtime->access) {
1684        case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1685        case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1686                info->first = info->channel * width;
1687                info->step = runtime->channels * width;
1688                break;
1689        case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1690        case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1691        {
1692                size_t size = runtime->dma_bytes / runtime->channels;
1693                info->first = info->channel * size * 8;
1694                info->step = width;
1695                break;
1696        }
1697        default:
1698                snd_BUG();
1699                break;
1700        }
1701        return 0;
1702}
1703
1704static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1705                                       void *arg)
1706{
1707        struct snd_pcm_hw_params *params = arg;
1708        snd_pcm_format_t format;
1709        int channels, width;
1710
1711        params->fifo_size = substream->runtime->hw.fifo_size;
1712        if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1713                format = params_format(params);
1714                channels = params_channels(params);
1715                width = snd_pcm_format_physical_width(format);
1716                params->fifo_size /= width * channels;
1717        }
1718        return 0;
1719}
1720
1721/**
1722 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1723 * @substream: the pcm substream instance
1724 * @cmd: ioctl command
1725 * @arg: ioctl argument
1726 *
1727 * Processes the generic ioctl commands for PCM.
1728 * Can be passed as the ioctl callback for PCM ops.
1729 *
1730 * Returns zero if successful, or a negative error code on failure.
1731 */
1732int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1733                      unsigned int cmd, void *arg)
1734{
1735        switch (cmd) {
1736        case SNDRV_PCM_IOCTL1_INFO:
1737                return 0;
1738        case SNDRV_PCM_IOCTL1_RESET:
1739                return snd_pcm_lib_ioctl_reset(substream, arg);
1740        case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1741                return snd_pcm_lib_ioctl_channel_info(substream, arg);
1742        case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1743                return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1744        }
1745        return -ENXIO;
1746}
1747
1748EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1749
1750/**
1751 * snd_pcm_period_elapsed - update the pcm status for the next period
1752 * @substream: the pcm substream instance
1753 *
1754 * This function is called from the interrupt handler when the
1755 * PCM has processed the period size.  It will update the current
1756 * pointer, wake up sleepers, etc.
1757 *
1758 * Even if more than one periods have elapsed since the last call, you
1759 * have to call this only once.
1760 */
1761void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1762{
1763        struct snd_pcm_runtime *runtime;
1764        unsigned long flags;
1765
1766        if (PCM_RUNTIME_CHECK(substream))
1767                return;
1768        runtime = substream->runtime;
1769
1770        if (runtime->transfer_ack_begin)
1771                runtime->transfer_ack_begin(substream);
1772
1773        snd_pcm_stream_lock_irqsave(substream, flags);
1774        if (!snd_pcm_running(substream) ||
1775            snd_pcm_update_hw_ptr0(substream, 1) < 0)
1776                goto _end;
1777
1778        if (substream->timer_running)
1779                snd_timer_interrupt(substream->timer, 1);
1780 _end:
1781        snd_pcm_stream_unlock_irqrestore(substream, flags);
1782        if (runtime->transfer_ack_end)
1783                runtime->transfer_ack_end(substream);
1784        kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1785}
1786
1787EXPORT_SYMBOL(snd_pcm_period_elapsed);
1788
1789/*
1790 * Wait until avail_min data becomes available
1791 * Returns a negative error code if any error occurs during operation.
1792 * The available space is stored on availp.  When err = 0 and avail = 0
1793 * on the capture stream, it indicates the stream is in DRAINING state.
1794 */
1795static int wait_for_avail(struct snd_pcm_substream *substream,
1796                              snd_pcm_uframes_t *availp)
1797{
1798        struct snd_pcm_runtime *runtime = substream->runtime;
1799        int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1800        wait_queue_t wait;
1801        int err = 0;
1802        snd_pcm_uframes_t avail = 0;
1803        long wait_time, tout;
1804
1805        init_waitqueue_entry(&wait, current);
1806        set_current_state(TASK_INTERRUPTIBLE);
1807        add_wait_queue(&runtime->tsleep, &wait);
1808
1809        if (runtime->no_period_wakeup)
1810                wait_time = MAX_SCHEDULE_TIMEOUT;
1811        else {
1812                wait_time = 10;
1813                if (runtime->rate) {
1814                        long t = runtime->period_size * 2 / runtime->rate;
1815                        wait_time = max(t, wait_time);
1816                }
1817                wait_time = msecs_to_jiffies(wait_time * 1000);
1818        }
1819
1820        for (;;) {
1821                if (signal_pending(current)) {
1822                        err = -ERESTARTSYS;
1823                        break;
1824                }
1825
1826                /*
1827                 * We need to check if space became available already
1828                 * (and thus the wakeup happened already) first to close
1829                 * the race of space already having become available.
1830                 * This check must happen after been added to the waitqueue
1831                 * and having current state be INTERRUPTIBLE.
1832                 */
1833                if (is_playback)
1834                        avail = snd_pcm_playback_avail(runtime);
1835                else
1836                        avail = snd_pcm_capture_avail(runtime);
1837                if (avail >= runtime->twake)
1838                        break;
1839                snd_pcm_stream_unlock_irq(substream);
1840
1841                tout = schedule_timeout(wait_time);
1842
1843                snd_pcm_stream_lock_irq(substream);
1844                set_current_state(TASK_INTERRUPTIBLE);
1845                switch (runtime->status->state) {
1846                case SNDRV_PCM_STATE_SUSPENDED:
1847                        err = -ESTRPIPE;
1848                        goto _endloop;
1849                case SNDRV_PCM_STATE_XRUN:
1850                        err = -EPIPE;
1851                        goto _endloop;
1852                case SNDRV_PCM_STATE_DRAINING:
1853                        if (is_playback)
1854                                err = -EPIPE;
1855                        else 
1856                                avail = 0; /* indicate draining */
1857                        goto _endloop;
1858                case SNDRV_PCM_STATE_OPEN:
1859                case SNDRV_PCM_STATE_SETUP:
1860                case SNDRV_PCM_STATE_DISCONNECTED:
1861                        err = -EBADFD;
1862                        goto _endloop;
1863                }
1864                if (!tout) {
1865                        snd_printd("%s write error (DMA or IRQ trouble?)\n",
1866                                   is_playback ? "playback" : "capture");
1867                        err = -EIO;
1868                        break;
1869                }
1870        }
1871 _endloop:
1872        set_current_state(TASK_RUNNING);
1873        remove_wait_queue(&runtime->tsleep, &wait);
1874        *availp = avail;
1875        return err;
1876}
1877        
1878static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1879                                      unsigned int hwoff,
1880                                      unsigned long data, unsigned int off,
1881                                      snd_pcm_uframes_t frames)
1882{
1883        struct snd_pcm_runtime *runtime = substream->runtime;
1884        int err;
1885        char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1886        if (substream->ops->copy) {
1887                if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1888                        return err;
1889        } else {
1890                char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1891                if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1892                        return -EFAULT;
1893        }
1894        return 0;
1895}
1896 
1897typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1898                          unsigned long data, unsigned int off,
1899                          snd_pcm_uframes_t size);
1900
1901static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream, 
1902                                            unsigned long data,
1903                                            snd_pcm_uframes_t size,
1904                                            int nonblock,
1905                                            transfer_f transfer)
1906{
1907        struct snd_pcm_runtime *runtime = substream->runtime;
1908        snd_pcm_uframes_t xfer = 0;
1909        snd_pcm_uframes_t offset = 0;
1910        snd_pcm_uframes_t avail;
1911        int err = 0;
1912
1913        if (size == 0)
1914                return 0;
1915
1916        snd_pcm_stream_lock_irq(substream);
1917        switch (runtime->status->state) {
1918        case SNDRV_PCM_STATE_PREPARED:
1919        case SNDRV_PCM_STATE_RUNNING:
1920        case SNDRV_PCM_STATE_PAUSED:
1921                break;
1922        case SNDRV_PCM_STATE_XRUN:
1923                err = -EPIPE;
1924                goto _end_unlock;
1925        case SNDRV_PCM_STATE_SUSPENDED:
1926                err = -ESTRPIPE;
1927                goto _end_unlock;
1928        default:
1929                err = -EBADFD;
1930                goto _end_unlock;
1931        }
1932
1933        runtime->twake = runtime->control->avail_min ? : 1;
1934        if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1935                snd_pcm_update_hw_ptr(substream);
1936        avail = snd_pcm_playback_avail(runtime);
1937        while (size > 0) {
1938                snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1939                snd_pcm_uframes_t cont;
1940                if (!avail) {
1941                        if (nonblock) {
1942                                err = -EAGAIN;
1943                                goto _end_unlock;
1944                        }
1945                        runtime->twake = min_t(snd_pcm_uframes_t, size,
1946                                        runtime->control->avail_min ? : 1);
1947                        err = wait_for_avail(substream, &avail);
1948                        if (err < 0)
1949                                goto _end_unlock;
1950                }
1951                frames = size > avail ? avail : size;
1952                cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1953                if (frames > cont)
1954                        frames = cont;
1955                if (snd_BUG_ON(!frames)) {
1956                        runtime->twake = 0;
1957                        snd_pcm_stream_unlock_irq(substream);
1958                        return -EINVAL;
1959                }
1960                appl_ptr = runtime->control->appl_ptr;
1961                appl_ofs = appl_ptr % runtime->buffer_size;
1962                snd_pcm_stream_unlock_irq(substream);
1963                err = transfer(substream, appl_ofs, data, offset, frames);
1964                snd_pcm_stream_lock_irq(substream);
1965                if (err < 0)
1966                        goto _end_unlock;
1967                switch (runtime->status->state) {
1968                case SNDRV_PCM_STATE_XRUN:
1969                        err = -EPIPE;
1970                        goto _end_unlock;
1971                case SNDRV_PCM_STATE_SUSPENDED:
1972                        err = -ESTRPIPE;
1973                        goto _end_unlock;
1974                default:
1975                        break;
1976                }
1977                appl_ptr += frames;
1978                if (appl_ptr >= runtime->boundary)
1979                        appl_ptr -= runtime->boundary;
1980                runtime->control->appl_ptr = appl_ptr;
1981                if (substream->ops->ack)
1982                        substream->ops->ack(substream);
1983
1984                offset += frames;
1985                size -= frames;
1986                xfer += frames;
1987                avail -= frames;
1988                if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1989                    snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1990                        err = snd_pcm_start(substream);
1991                        if (err < 0)
1992                                goto _end_unlock;
1993                }
1994        }
1995 _end_unlock:
1996        runtime->twake = 0;
1997        if (xfer > 0 && err >= 0)
1998                snd_pcm_update_state(substream, runtime);
1999        snd_pcm_stream_unlock_irq(substream);
2000        return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2001}
2002
2003/* sanity-check for read/write methods */
2004static int pcm_sanity_check(struct snd_pcm_substream *substream)
2005{
2006        struct snd_pcm_runtime *runtime;
2007        if (PCM_RUNTIME_CHECK(substream))
2008                return -ENXIO;
2009        runtime = substream->runtime;
2010        if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
2011                return -EINVAL;
2012        if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2013                return -EBADFD;
2014        return 0;
2015}
2016
2017snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
2018{
2019        struct snd_pcm_runtime *runtime;
2020        int nonblock;
2021        int err;
2022
2023        err = pcm_sanity_check(substream);
2024        if (err < 0)
2025                return err;
2026        runtime = substream->runtime;
2027        nonblock = !!(substream->f_flags & O_NONBLOCK);
2028
2029        if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2030            runtime->channels > 1)
2031                return -EINVAL;
2032        return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
2033                                  snd_pcm_lib_write_transfer);
2034}
2035
2036EXPORT_SYMBOL(snd_pcm_lib_write);
2037
2038static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
2039                                       unsigned int hwoff,
2040                                       unsigned long data, unsigned int off,
2041                                       snd_pcm_uframes_t frames)
2042{
2043        struct snd_pcm_runtime *runtime = substream->runtime;
2044        int err;
2045        void __user **bufs = (void __user **)data;
2046        int channels = runtime->channels;
2047        int c;
2048        if (substream->ops->copy) {
2049                if (snd_BUG_ON(!substream->ops->silence))
2050                        return -EINVAL;
2051                for (c = 0; c < channels; ++c, ++bufs) {
2052                        if (*bufs == NULL) {
2053                                if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
2054                                        return err;
2055                        } else {
2056                                char __user *buf = *bufs + samples_to_bytes(runtime, off);
2057                                if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2058                                        return err;
2059                        }
2060                }
2061        } else {
2062                /* default transfer behaviour */
2063                size_t dma_csize = runtime->dma_bytes / channels;
2064                for (c = 0; c < channels; ++c, ++bufs) {
2065                        char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2066                        if (*bufs == NULL) {
2067                                snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
2068                        } else {
2069                                char __user *buf = *bufs + samples_to_bytes(runtime, off);
2070                                if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
2071                                        return -EFAULT;
2072                        }
2073                }
2074        }
2075        return 0;
2076}
2077 
2078snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
2079                                     void __user **bufs,
2080                                     snd_pcm_uframes_t frames)
2081{
2082        struct snd_pcm_runtime *runtime;
2083        int nonblock;
2084        int err;
2085
2086        err = pcm_sanity_check(substream);
2087        if (err < 0)
2088                return err;
2089        runtime = substream->runtime;
2090        nonblock = !!(substream->f_flags & O_NONBLOCK);
2091
2092        if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2093                return -EINVAL;
2094        return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2095                                  nonblock, snd_pcm_lib_writev_transfer);
2096}
2097
2098EXPORT_SYMBOL(snd_pcm_lib_writev);
2099
2100static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream, 
2101                                     unsigned int hwoff,
2102                                     unsigned long data, unsigned int off,
2103                                     snd_pcm_uframes_t frames)
2104{
2105        struct snd_pcm_runtime *runtime = substream->runtime;
2106        int err;
2107        char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2108        if (substream->ops->copy) {
2109                if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2110                        return err;
2111        } else {
2112                char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2113                if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2114                        return -EFAULT;
2115        }
2116        return 0;
2117}
2118
2119static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2120                                           unsigned long data,
2121                                           snd_pcm_uframes_t size,
2122                                           int nonblock,
2123                                           transfer_f transfer)
2124{
2125        struct snd_pcm_runtime *runtime = substream->runtime;
2126        snd_pcm_uframes_t xfer = 0;
2127        snd_pcm_uframes_t offset = 0;
2128        snd_pcm_uframes_t avail;
2129        int err = 0;
2130
2131        if (size == 0)
2132                return 0;
2133
2134        snd_pcm_stream_lock_irq(substream);
2135        switch (runtime->status->state) {
2136        case SNDRV_PCM_STATE_PREPARED:
2137                if (size >= runtime->start_threshold) {
2138                        err = snd_pcm_start(substream);
2139                        if (err < 0)
2140                                goto _end_unlock;
2141                }
2142                break;
2143        case SNDRV_PCM_STATE_DRAINING:
2144        case SNDRV_PCM_STATE_RUNNING:
2145        case SNDRV_PCM_STATE_PAUSED:
2146                break;
2147        case SNDRV_PCM_STATE_XRUN:
2148                err = -EPIPE;
2149                goto _end_unlock;
2150        case SNDRV_PCM_STATE_SUSPENDED:
2151                err = -ESTRPIPE;
2152                goto _end_unlock;
2153        default:
2154                err = -EBADFD;
2155                goto _end_unlock;
2156        }
2157
2158        runtime->twake = runtime->control->avail_min ? : 1;
2159        if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2160                snd_pcm_update_hw_ptr(substream);
2161        avail = snd_pcm_capture_avail(runtime);
2162        while (size > 0) {
2163                snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2164                snd_pcm_uframes_t cont;
2165                if (!avail) {
2166                        if (runtime->status->state ==
2167                            SNDRV_PCM_STATE_DRAINING) {
2168                                snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2169                                goto _end_unlock;
2170                        }
2171                        if (nonblock) {
2172                                err = -EAGAIN;
2173                                goto _end_unlock;
2174                        }
2175                        runtime->twake = min_t(snd_pcm_uframes_t, size,
2176                                        runtime->control->avail_min ? : 1);
2177                        err = wait_for_avail(substream, &avail);
2178                        if (err < 0)
2179                                goto _end_unlock;
2180                        if (!avail)
2181                                continue; /* draining */
2182                }
2183                frames = size > avail ? avail : size;
2184                cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2185                if (frames > cont)
2186                        frames = cont;
2187                if (snd_BUG_ON(!frames)) {
2188                        runtime->twake = 0;
2189                        snd_pcm_stream_unlock_irq(substream);
2190                        return -EINVAL;
2191                }
2192                appl_ptr = runtime->control->appl_ptr;
2193                appl_ofs = appl_ptr % runtime->buffer_size;
2194                snd_pcm_stream_unlock_irq(substream);
2195                err = transfer(substream, appl_ofs, data, offset, frames);
2196                snd_pcm_stream_lock_irq(substream);
2197                if (err < 0)
2198                        goto _end_unlock;
2199                switch (runtime->status->state) {
2200                case SNDRV_PCM_STATE_XRUN:
2201                        err = -EPIPE;
2202                        goto _end_unlock;
2203                case SNDRV_PCM_STATE_SUSPENDED:
2204                        err = -ESTRPIPE;
2205                        goto _end_unlock;
2206                default:
2207                        break;
2208                }
2209                appl_ptr += frames;
2210                if (appl_ptr >= runtime->boundary)
2211                        appl_ptr -= runtime->boundary;
2212                runtime->control->appl_ptr = appl_ptr;
2213                if (substream->ops->ack)
2214                        substream->ops->ack(substream);
2215
2216                offset += frames;
2217                size -= frames;
2218                xfer += frames;
2219                avail -= frames;
2220        }
2221 _end_unlock:
2222        runtime->twake = 0;
2223        if (xfer > 0 && err >= 0)
2224                snd_pcm_update_state(substream, runtime);
2225        snd_pcm_stream_unlock_irq(substream);
2226        return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2227}
2228
2229snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2230{
2231        struct snd_pcm_runtime *runtime;
2232        int nonblock;
2233        int err;
2234        
2235        err = pcm_sanity_check(substream);
2236        if (err < 0)
2237                return err;
2238        runtime = substream->runtime;
2239        nonblock = !!(substream->f_flags & O_NONBLOCK);
2240        if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2241                return -EINVAL;
2242        return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2243}
2244
2245EXPORT_SYMBOL(snd_pcm_lib_read);
2246
2247static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2248                                      unsigned int hwoff,
2249                                      unsigned long data, unsigned int off,
2250                                      snd_pcm_uframes_t frames)
2251{
2252        struct snd_pcm_runtime *runtime = substream->runtime;
2253        int err;
2254        void __user **bufs = (void __user **)data;
2255        int channels = runtime->channels;
2256        int c;
2257        if (substream->ops->copy) {
2258                for (c = 0; c < channels; ++c, ++bufs) {
2259                        char __user *buf;
2260                        if (*bufs == NULL)
2261                                continue;
2262                        buf = *bufs + samples_to_bytes(runtime, off);
2263                        if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2264                                return err;
2265                }
2266        } else {
2267                snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2268                for (c = 0; c < channels; ++c, ++bufs) {
2269                        char *hwbuf;
2270                        char __user *buf;
2271                        if (*bufs == NULL)
2272                                continue;
2273
2274                        hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2275                        buf = *bufs + samples_to_bytes(runtime, off);
2276                        if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2277                                return -EFAULT;
2278                }
2279        }
2280        return 0;
2281}
2282 
2283snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2284                                    void __user **bufs,
2285                                    snd_pcm_uframes_t frames)
2286{
2287        struct snd_pcm_runtime *runtime;
2288        int nonblock;
2289        int err;
2290
2291        err = pcm_sanity_check(substream);
2292        if (err < 0)
2293                return err;
2294        runtime = substream->runtime;
2295        if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2296                return -EBADFD;
2297
2298        nonblock = !!(substream->f_flags & O_NONBLOCK);
2299        if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2300                return -EINVAL;
2301        return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2302}
2303
2304EXPORT_SYMBOL(snd_pcm_lib_readv);
2305
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