linux/sound/core/pcm_lib.c
<<
>>
Prefs
   1/*
   2 *  Digital Audio (PCM) abstract layer
   3 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   4 *                   Abramo Bagnara <abramo@alsa-project.org>
   5 *
   6 *
   7 *   This program is free software; you can redistribute it and/or modify
   8 *   it under the terms of the GNU General Public License as published by
   9 *   the Free Software Foundation; either version 2 of the License, or
  10 *   (at your option) any later version.
  11 *
  12 *   This program is distributed in the hope that it will be useful,
  13 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 *   GNU General Public License for more details.
  16 *
  17 *   You should have received a copy of the GNU General Public License
  18 *   along with this program; if not, write to the Free Software
  19 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  20 *
  21 */
  22
  23#include <linux/slab.h>
  24#include <linux/time.h>
  25#include <linux/math64.h>
  26#include <linux/export.h>
  27#include <sound/core.h>
  28#include <sound/control.h>
  29#include <sound/tlv.h>
  30#include <sound/info.h>
  31#include <sound/pcm.h>
  32#include <sound/pcm_params.h>
  33#include <sound/timer.h>
  34
  35/*
  36 * fill ring buffer with silence
  37 * runtime->silence_start: starting pointer to silence area
  38 * runtime->silence_filled: size filled with silence
  39 * runtime->silence_threshold: threshold from application
  40 * runtime->silence_size: maximal size from application
  41 *
  42 * when runtime->silence_size >= runtime->boundary - fill processed area with silence immediately
  43 */
  44void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr)
  45{
  46        struct snd_pcm_runtime *runtime = substream->runtime;
  47        snd_pcm_uframes_t frames, ofs, transfer;
  48
  49        if (runtime->silence_size < runtime->boundary) {
  50                snd_pcm_sframes_t noise_dist, n;
  51                if (runtime->silence_start != runtime->control->appl_ptr) {
  52                        n = runtime->control->appl_ptr - runtime->silence_start;
  53                        if (n < 0)
  54                                n += runtime->boundary;
  55                        if ((snd_pcm_uframes_t)n < runtime->silence_filled)
  56                                runtime->silence_filled -= n;
  57                        else
  58                                runtime->silence_filled = 0;
  59                        runtime->silence_start = runtime->control->appl_ptr;
  60                }
  61                if (runtime->silence_filled >= runtime->buffer_size)
  62                        return;
  63                noise_dist = snd_pcm_playback_hw_avail(runtime) + runtime->silence_filled;
  64                if (noise_dist >= (snd_pcm_sframes_t) runtime->silence_threshold)
  65                        return;
  66                frames = runtime->silence_threshold - noise_dist;
  67                if (frames > runtime->silence_size)
  68                        frames = runtime->silence_size;
  69        } else {
  70                if (new_hw_ptr == ULONG_MAX) {  /* initialization */
  71                        snd_pcm_sframes_t avail = snd_pcm_playback_hw_avail(runtime);
  72                        if (avail > runtime->buffer_size)
  73                                avail = runtime->buffer_size;
  74                        runtime->silence_filled = avail > 0 ? avail : 0;
  75                        runtime->silence_start = (runtime->status->hw_ptr +
  76                                                  runtime->silence_filled) %
  77                                                 runtime->boundary;
  78                } else {
  79                        ofs = runtime->status->hw_ptr;
  80                        frames = new_hw_ptr - ofs;
  81                        if ((snd_pcm_sframes_t)frames < 0)
  82                                frames += runtime->boundary;
  83                        runtime->silence_filled -= frames;
  84                        if ((snd_pcm_sframes_t)runtime->silence_filled < 0) {
  85                                runtime->silence_filled = 0;
  86                                runtime->silence_start = new_hw_ptr;
  87                        } else {
  88                                runtime->silence_start = ofs;
  89                        }
  90                }
  91                frames = runtime->buffer_size - runtime->silence_filled;
  92        }
  93        if (snd_BUG_ON(frames > runtime->buffer_size))
  94                return;
  95        if (frames == 0)
  96                return;
  97        ofs = runtime->silence_start % runtime->buffer_size;
  98        while (frames > 0) {
  99                transfer = ofs + frames > runtime->buffer_size ? runtime->buffer_size - ofs : frames;
 100                if (runtime->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED ||
 101                    runtime->access == SNDRV_PCM_ACCESS_MMAP_INTERLEAVED) {
 102                        if (substream->ops->silence) {
 103                                int err;
 104                                err = substream->ops->silence(substream, -1, ofs, transfer);
 105                                snd_BUG_ON(err < 0);
 106                        } else {
 107                                char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, ofs);
 108                                snd_pcm_format_set_silence(runtime->format, hwbuf, transfer * runtime->channels);
 109                        }
 110                } else {
 111                        unsigned int c;
 112                        unsigned int channels = runtime->channels;
 113                        if (substream->ops->silence) {
 114                                for (c = 0; c < channels; ++c) {
 115                                        int err;
 116                                        err = substream->ops->silence(substream, c, ofs, transfer);
 117                                        snd_BUG_ON(err < 0);
 118                                }
 119                        } else {
 120                                size_t dma_csize = runtime->dma_bytes / channels;
 121                                for (c = 0; c < channels; ++c) {
 122                                        char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, ofs);
 123                                        snd_pcm_format_set_silence(runtime->format, hwbuf, transfer);
 124                                }
 125                        }
 126                }
 127                runtime->silence_filled += transfer;
 128                frames -= transfer;
 129                ofs = 0;
 130        }
 131}
 132
 133#ifdef CONFIG_SND_DEBUG
 134void snd_pcm_debug_name(struct snd_pcm_substream *substream,
 135                           char *name, size_t len)
 136{
 137        snprintf(name, len, "pcmC%dD%d%c:%d",
 138                 substream->pcm->card->number,
 139                 substream->pcm->device,
 140                 substream->stream ? 'c' : 'p',
 141                 substream->number);
 142}
 143EXPORT_SYMBOL(snd_pcm_debug_name);
 144#endif
 145
 146#define XRUN_DEBUG_BASIC        (1<<0)
 147#define XRUN_DEBUG_STACK        (1<<1)  /* dump also stack */
 148#define XRUN_DEBUG_JIFFIESCHECK (1<<2)  /* do jiffies check */
 149#define XRUN_DEBUG_PERIODUPDATE (1<<3)  /* full period update info */
 150#define XRUN_DEBUG_HWPTRUPDATE  (1<<4)  /* full hwptr update info */
 151#define XRUN_DEBUG_LOG          (1<<5)  /* show last 10 positions on err */
 152#define XRUN_DEBUG_LOGONCE      (1<<6)  /* do above only once */
 153
 154#ifdef CONFIG_SND_PCM_XRUN_DEBUG
 155
 156#define xrun_debug(substream, mask) \
 157                        ((substream)->pstr->xrun_debug & (mask))
 158#else
 159#define xrun_debug(substream, mask)     0
 160#endif
 161
 162#define dump_stack_on_xrun(substream) do {                      \
 163                if (xrun_debug(substream, XRUN_DEBUG_STACK))    \
 164                        dump_stack();                           \
 165        } while (0)
 166
 167static void xrun(struct snd_pcm_substream *substream)
 168{
 169        struct snd_pcm_runtime *runtime = substream->runtime;
 170
 171        if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
 172                snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp);
 173        snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 174        if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {
 175                char name[16];
 176                snd_pcm_debug_name(substream, name, sizeof(name));
 177                snd_printd(KERN_DEBUG "XRUN: %s\n", name);
 178                dump_stack_on_xrun(substream);
 179        }
 180}
 181
 182#ifdef CONFIG_SND_PCM_XRUN_DEBUG
 183#define hw_ptr_error(substream, fmt, args...)                           \
 184        do {                                                            \
 185                if (xrun_debug(substream, XRUN_DEBUG_BASIC)) {          \
 186                        xrun_log_show(substream);                       \
 187                        if (printk_ratelimit()) {                       \
 188                                snd_printd("PCM: " fmt, ##args);        \
 189                        }                                               \
 190                        dump_stack_on_xrun(substream);                  \
 191                }                                                       \
 192        } while (0)
 193
 194#define XRUN_LOG_CNT    10
 195
 196struct hwptr_log_entry {
 197        unsigned int in_interrupt;
 198        unsigned long jiffies;
 199        snd_pcm_uframes_t pos;
 200        snd_pcm_uframes_t period_size;
 201        snd_pcm_uframes_t buffer_size;
 202        snd_pcm_uframes_t old_hw_ptr;
 203        snd_pcm_uframes_t hw_ptr_base;
 204};
 205
 206struct snd_pcm_hwptr_log {
 207        unsigned int idx;
 208        unsigned int hit: 1;
 209        struct hwptr_log_entry entries[XRUN_LOG_CNT];
 210};
 211
 212static void xrun_log(struct snd_pcm_substream *substream,
 213                     snd_pcm_uframes_t pos, int in_interrupt)
 214{
 215        struct snd_pcm_runtime *runtime = substream->runtime;
 216        struct snd_pcm_hwptr_log *log = runtime->hwptr_log;
 217        struct hwptr_log_entry *entry;
 218
 219        if (log == NULL) {
 220                log = kzalloc(sizeof(*log), GFP_ATOMIC);
 221                if (log == NULL)
 222                        return;
 223                runtime->hwptr_log = log;
 224        } else {
 225                if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
 226                        return;
 227        }
 228        entry = &log->entries[log->idx];
 229        entry->in_interrupt = in_interrupt;
 230        entry->jiffies = jiffies;
 231        entry->pos = pos;
 232        entry->period_size = runtime->period_size;
 233        entry->buffer_size = runtime->buffer_size;
 234        entry->old_hw_ptr = runtime->status->hw_ptr;
 235        entry->hw_ptr_base = runtime->hw_ptr_base;
 236        log->idx = (log->idx + 1) % XRUN_LOG_CNT;
 237}
 238
 239static void xrun_log_show(struct snd_pcm_substream *substream)
 240{
 241        struct snd_pcm_hwptr_log *log = substream->runtime->hwptr_log;
 242        struct hwptr_log_entry *entry;
 243        char name[16];
 244        unsigned int idx;
 245        int cnt;
 246
 247        if (log == NULL)
 248                return;
 249        if (xrun_debug(substream, XRUN_DEBUG_LOGONCE) && log->hit)
 250                return;
 251        snd_pcm_debug_name(substream, name, sizeof(name));
 252        for (cnt = 0, idx = log->idx; cnt < XRUN_LOG_CNT; cnt++) {
 253                entry = &log->entries[idx];
 254                if (entry->period_size == 0)
 255                        break;
 256                snd_printd("hwptr log: %s: %sj=%lu, pos=%ld/%ld/%ld, "
 257                           "hwptr=%ld/%ld\n",
 258                           name, entry->in_interrupt ? "[Q] " : "",
 259                           entry->jiffies,
 260                           (unsigned long)entry->pos,
 261                           (unsigned long)entry->period_size,
 262                           (unsigned long)entry->buffer_size,
 263                           (unsigned long)entry->old_hw_ptr,
 264                           (unsigned long)entry->hw_ptr_base);
 265                idx++;
 266                idx %= XRUN_LOG_CNT;
 267        }
 268        log->hit = 1;
 269}
 270
 271#else /* ! CONFIG_SND_PCM_XRUN_DEBUG */
 272
 273#define hw_ptr_error(substream, fmt, args...) do { } while (0)
 274#define xrun_log(substream, pos, in_interrupt)  do { } while (0)
 275#define xrun_log_show(substream)        do { } while (0)
 276
 277#endif
 278
 279int snd_pcm_update_state(struct snd_pcm_substream *substream,
 280                         struct snd_pcm_runtime *runtime)
 281{
 282        snd_pcm_uframes_t avail;
 283
 284        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 285                avail = snd_pcm_playback_avail(runtime);
 286        else
 287                avail = snd_pcm_capture_avail(runtime);
 288        if (avail > runtime->avail_max)
 289                runtime->avail_max = avail;
 290        if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
 291                if (avail >= runtime->buffer_size) {
 292                        snd_pcm_drain_done(substream);
 293                        return -EPIPE;
 294                }
 295        } else {
 296                if (avail >= runtime->stop_threshold) {
 297                        xrun(substream);
 298                        return -EPIPE;
 299                }
 300        }
 301        if (runtime->twake) {
 302                if (avail >= runtime->twake)
 303                        wake_up(&runtime->tsleep);
 304        } else if (avail >= runtime->control->avail_min)
 305                wake_up(&runtime->sleep);
 306        return 0;
 307}
 308
 309static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream,
 310                                  unsigned int in_interrupt)
 311{
 312        struct snd_pcm_runtime *runtime = substream->runtime;
 313        snd_pcm_uframes_t pos;
 314        snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
 315        snd_pcm_sframes_t hdelta, delta;
 316        unsigned long jdelta;
 317        unsigned long curr_jiffies;
 318        struct timespec curr_tstamp;
 319
 320        old_hw_ptr = runtime->status->hw_ptr;
 321
 322        /*
 323         * group pointer, time and jiffies reads to allow for more
 324         * accurate correlations/corrections.
 325         * The values are stored at the end of this routine after
 326         * corrections for hw_ptr position
 327         */
 328        pos = substream->ops->pointer(substream);
 329        curr_jiffies = jiffies;
 330        if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
 331                snd_pcm_gettime(runtime, (struct timespec *)&curr_tstamp);
 332
 333        if (pos == SNDRV_PCM_POS_XRUN) {
 334                xrun(substream);
 335                return -EPIPE;
 336        }
 337        if (pos >= runtime->buffer_size) {
 338                if (printk_ratelimit()) {
 339                        char name[16];
 340                        snd_pcm_debug_name(substream, name, sizeof(name));
 341                        xrun_log_show(substream);
 342                        snd_printd(KERN_ERR  "BUG: %s, pos = %ld, "
 343                                   "buffer size = %ld, period size = %ld\n",
 344                                   name, pos, runtime->buffer_size,
 345                                   runtime->period_size);
 346                }
 347                pos = 0;
 348        }
 349        pos -= pos % runtime->min_align;
 350        if (xrun_debug(substream, XRUN_DEBUG_LOG))
 351                xrun_log(substream, pos, in_interrupt);
 352        hw_base = runtime->hw_ptr_base;
 353        new_hw_ptr = hw_base + pos;
 354        if (in_interrupt) {
 355                /* we know that one period was processed */
 356                /* delta = "expected next hw_ptr" for in_interrupt != 0 */
 357                delta = runtime->hw_ptr_interrupt + runtime->period_size;
 358                if (delta > new_hw_ptr) {
 359                        /* check for double acknowledged interrupts */
 360                        hdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 361                        if (hdelta > runtime->hw_ptr_buffer_jiffies/2) {
 362                                hw_base += runtime->buffer_size;
 363                                if (hw_base >= runtime->boundary)
 364                                        hw_base = 0;
 365                                new_hw_ptr = hw_base + pos;
 366                                goto __delta;
 367                        }
 368                }
 369        }
 370        /* new_hw_ptr might be lower than old_hw_ptr in case when */
 371        /* pointer crosses the end of the ring buffer */
 372        if (new_hw_ptr < old_hw_ptr) {
 373                hw_base += runtime->buffer_size;
 374                if (hw_base >= runtime->boundary)
 375                        hw_base = 0;
 376                new_hw_ptr = hw_base + pos;
 377        }
 378      __delta:
 379        delta = new_hw_ptr - old_hw_ptr;
 380        if (delta < 0)
 381                delta += runtime->boundary;
 382        if (xrun_debug(substream, in_interrupt ?
 383                        XRUN_DEBUG_PERIODUPDATE : XRUN_DEBUG_HWPTRUPDATE)) {
 384                char name[16];
 385                snd_pcm_debug_name(substream, name, sizeof(name));
 386                snd_printd("%s_update: %s: pos=%u/%u/%u, "
 387                           "hwptr=%ld/%ld/%ld/%ld\n",
 388                           in_interrupt ? "period" : "hwptr",
 389                           name,
 390                           (unsigned int)pos,
 391                           (unsigned int)runtime->period_size,
 392                           (unsigned int)runtime->buffer_size,
 393                           (unsigned long)delta,
 394                           (unsigned long)old_hw_ptr,
 395                           (unsigned long)new_hw_ptr,
 396                           (unsigned long)runtime->hw_ptr_base);
 397        }
 398
 399        if (runtime->no_period_wakeup) {
 400                snd_pcm_sframes_t xrun_threshold;
 401                /*
 402                 * Without regular period interrupts, we have to check
 403                 * the elapsed time to detect xruns.
 404                 */
 405                jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 406                if (jdelta < runtime->hw_ptr_buffer_jiffies / 2)
 407                        goto no_delta_check;
 408                hdelta = jdelta - delta * HZ / runtime->rate;
 409                xrun_threshold = runtime->hw_ptr_buffer_jiffies / 2 + 1;
 410                while (hdelta > xrun_threshold) {
 411                        delta += runtime->buffer_size;
 412                        hw_base += runtime->buffer_size;
 413                        if (hw_base >= runtime->boundary)
 414                                hw_base = 0;
 415                        new_hw_ptr = hw_base + pos;
 416                        hdelta -= runtime->hw_ptr_buffer_jiffies;
 417                }
 418                goto no_delta_check;
 419        }
 420
 421        /* something must be really wrong */
 422        if (delta >= runtime->buffer_size + runtime->period_size) {
 423                hw_ptr_error(substream,
 424                               "Unexpected hw_pointer value %s"
 425                               "(stream=%i, pos=%ld, new_hw_ptr=%ld, "
 426                               "old_hw_ptr=%ld)\n",
 427                                     in_interrupt ? "[Q] " : "[P]",
 428                                     substream->stream, (long)pos,
 429                                     (long)new_hw_ptr, (long)old_hw_ptr);
 430                return 0;
 431        }
 432
 433        /* Do jiffies check only in xrun_debug mode */
 434        if (!xrun_debug(substream, XRUN_DEBUG_JIFFIESCHECK))
 435                goto no_jiffies_check;
 436
 437        /* Skip the jiffies check for hardwares with BATCH flag.
 438         * Such hardware usually just increases the position at each IRQ,
 439         * thus it can't give any strange position.
 440         */
 441        if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
 442                goto no_jiffies_check;
 443        hdelta = delta;
 444        if (hdelta < runtime->delay)
 445                goto no_jiffies_check;
 446        hdelta -= runtime->delay;
 447        jdelta = curr_jiffies - runtime->hw_ptr_jiffies;
 448        if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
 449                delta = jdelta /
 450                        (((runtime->period_size * HZ) / runtime->rate)
 451                                                                + HZ/100);
 452                /* move new_hw_ptr according jiffies not pos variable */
 453                new_hw_ptr = old_hw_ptr;
 454                hw_base = delta;
 455                /* use loop to avoid checks for delta overflows */
 456                /* the delta value is small or zero in most cases */
 457                while (delta > 0) {
 458                        new_hw_ptr += runtime->period_size;
 459                        if (new_hw_ptr >= runtime->boundary)
 460                                new_hw_ptr -= runtime->boundary;
 461                        delta--;
 462                }
 463                /* align hw_base to buffer_size */
 464                hw_ptr_error(substream,
 465                             "hw_ptr skipping! %s"
 466                             "(pos=%ld, delta=%ld, period=%ld, "
 467                             "jdelta=%lu/%lu/%lu, hw_ptr=%ld/%ld)\n",
 468                             in_interrupt ? "[Q] " : "",
 469                             (long)pos, (long)hdelta,
 470                             (long)runtime->period_size, jdelta,
 471                             ((hdelta * HZ) / runtime->rate), hw_base,
 472                             (unsigned long)old_hw_ptr,
 473                             (unsigned long)new_hw_ptr);
 474                /* reset values to proper state */
 475                delta = 0;
 476                hw_base = new_hw_ptr - (new_hw_ptr % runtime->buffer_size);
 477        }
 478 no_jiffies_check:
 479        if (delta > runtime->period_size + runtime->period_size / 2) {
 480                hw_ptr_error(substream,
 481                             "Lost interrupts? %s"
 482                             "(stream=%i, delta=%ld, new_hw_ptr=%ld, "
 483                             "old_hw_ptr=%ld)\n",
 484                             in_interrupt ? "[Q] " : "",
 485                             substream->stream, (long)delta,
 486                             (long)new_hw_ptr,
 487                             (long)old_hw_ptr);
 488        }
 489
 490 no_delta_check:
 491        if (runtime->status->hw_ptr == new_hw_ptr)
 492                return 0;
 493
 494        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 495            runtime->silence_size > 0)
 496                snd_pcm_playback_silence(substream, new_hw_ptr);
 497
 498        if (in_interrupt) {
 499                delta = new_hw_ptr - runtime->hw_ptr_interrupt;
 500                if (delta < 0)
 501                        delta += runtime->boundary;
 502                delta -= (snd_pcm_uframes_t)delta % runtime->period_size;
 503                runtime->hw_ptr_interrupt += delta;
 504                if (runtime->hw_ptr_interrupt >= runtime->boundary)
 505                        runtime->hw_ptr_interrupt -= runtime->boundary;
 506        }
 507        runtime->hw_ptr_base = hw_base;
 508        runtime->status->hw_ptr = new_hw_ptr;
 509        runtime->hw_ptr_jiffies = curr_jiffies;
 510        if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE)
 511                runtime->status->tstamp = curr_tstamp;
 512
 513        return snd_pcm_update_state(substream, runtime);
 514}
 515
 516/* CAUTION: call it with irq disabled */
 517int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
 518{
 519        return snd_pcm_update_hw_ptr0(substream, 0);
 520}
 521
 522/**
 523 * snd_pcm_set_ops - set the PCM operators
 524 * @pcm: the pcm instance
 525 * @direction: stream direction, SNDRV_PCM_STREAM_XXX
 526 * @ops: the operator table
 527 *
 528 * Sets the given PCM operators to the pcm instance.
 529 */
 530void snd_pcm_set_ops(struct snd_pcm *pcm, int direction, struct snd_pcm_ops *ops)
 531{
 532        struct snd_pcm_str *stream = &pcm->streams[direction];
 533        struct snd_pcm_substream *substream;
 534        
 535        for (substream = stream->substream; substream != NULL; substream = substream->next)
 536                substream->ops = ops;
 537}
 538
 539EXPORT_SYMBOL(snd_pcm_set_ops);
 540
 541/**
 542 * snd_pcm_sync - set the PCM sync id
 543 * @substream: the pcm substream
 544 *
 545 * Sets the PCM sync identifier for the card.
 546 */
 547void snd_pcm_set_sync(struct snd_pcm_substream *substream)
 548{
 549        struct snd_pcm_runtime *runtime = substream->runtime;
 550        
 551        runtime->sync.id32[0] = substream->pcm->card->number;
 552        runtime->sync.id32[1] = -1;
 553        runtime->sync.id32[2] = -1;
 554        runtime->sync.id32[3] = -1;
 555}
 556
 557EXPORT_SYMBOL(snd_pcm_set_sync);
 558
 559/*
 560 *  Standard ioctl routine
 561 */
 562
 563static inline unsigned int div32(unsigned int a, unsigned int b, 
 564                                 unsigned int *r)
 565{
 566        if (b == 0) {
 567                *r = 0;
 568                return UINT_MAX;
 569        }
 570        *r = a % b;
 571        return a / b;
 572}
 573
 574static inline unsigned int div_down(unsigned int a, unsigned int b)
 575{
 576        if (b == 0)
 577                return UINT_MAX;
 578        return a / b;
 579}
 580
 581static inline unsigned int div_up(unsigned int a, unsigned int b)
 582{
 583        unsigned int r;
 584        unsigned int q;
 585        if (b == 0)
 586                return UINT_MAX;
 587        q = div32(a, b, &r);
 588        if (r)
 589                ++q;
 590        return q;
 591}
 592
 593static inline unsigned int mul(unsigned int a, unsigned int b)
 594{
 595        if (a == 0)
 596                return 0;
 597        if (div_down(UINT_MAX, a) < b)
 598                return UINT_MAX;
 599        return a * b;
 600}
 601
 602static inline unsigned int muldiv32(unsigned int a, unsigned int b,
 603                                    unsigned int c, unsigned int *r)
 604{
 605        u_int64_t n = (u_int64_t) a * b;
 606        if (c == 0) {
 607                snd_BUG_ON(!n);
 608                *r = 0;
 609                return UINT_MAX;
 610        }
 611        n = div_u64_rem(n, c, r);
 612        if (n >= UINT_MAX) {
 613                *r = 0;
 614                return UINT_MAX;
 615        }
 616        return n;
 617}
 618
 619/**
 620 * snd_interval_refine - refine the interval value of configurator
 621 * @i: the interval value to refine
 622 * @v: the interval value to refer to
 623 *
 624 * Refines the interval value with the reference value.
 625 * The interval is changed to the range satisfying both intervals.
 626 * The interval status (min, max, integer, etc.) are evaluated.
 627 *
 628 * Returns non-zero if the value is changed, zero if not changed.
 629 */
 630int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v)
 631{
 632        int changed = 0;
 633        if (snd_BUG_ON(snd_interval_empty(i)))
 634                return -EINVAL;
 635        if (i->min < v->min) {
 636                i->min = v->min;
 637                i->openmin = v->openmin;
 638                changed = 1;
 639        } else if (i->min == v->min && !i->openmin && v->openmin) {
 640                i->openmin = 1;
 641                changed = 1;
 642        }
 643        if (i->max > v->max) {
 644                i->max = v->max;
 645                i->openmax = v->openmax;
 646                changed = 1;
 647        } else if (i->max == v->max && !i->openmax && v->openmax) {
 648                i->openmax = 1;
 649                changed = 1;
 650        }
 651        if (!i->integer && v->integer) {
 652                i->integer = 1;
 653                changed = 1;
 654        }
 655        if (i->integer) {
 656                if (i->openmin) {
 657                        i->min++;
 658                        i->openmin = 0;
 659                }
 660                if (i->openmax) {
 661                        i->max--;
 662                        i->openmax = 0;
 663                }
 664        } else if (!i->openmin && !i->openmax && i->min == i->max)
 665                i->integer = 1;
 666        if (snd_interval_checkempty(i)) {
 667                snd_interval_none(i);
 668                return -EINVAL;
 669        }
 670        return changed;
 671}
 672
 673EXPORT_SYMBOL(snd_interval_refine);
 674
 675static int snd_interval_refine_first(struct snd_interval *i)
 676{
 677        if (snd_BUG_ON(snd_interval_empty(i)))
 678                return -EINVAL;
 679        if (snd_interval_single(i))
 680                return 0;
 681        i->max = i->min;
 682        i->openmax = i->openmin;
 683        if (i->openmax)
 684                i->max++;
 685        return 1;
 686}
 687
 688static int snd_interval_refine_last(struct snd_interval *i)
 689{
 690        if (snd_BUG_ON(snd_interval_empty(i)))
 691                return -EINVAL;
 692        if (snd_interval_single(i))
 693                return 0;
 694        i->min = i->max;
 695        i->openmin = i->openmax;
 696        if (i->openmin)
 697                i->min--;
 698        return 1;
 699}
 700
 701void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 702{
 703        if (a->empty || b->empty) {
 704                snd_interval_none(c);
 705                return;
 706        }
 707        c->empty = 0;
 708        c->min = mul(a->min, b->min);
 709        c->openmin = (a->openmin || b->openmin);
 710        c->max = mul(a->max,  b->max);
 711        c->openmax = (a->openmax || b->openmax);
 712        c->integer = (a->integer && b->integer);
 713}
 714
 715/**
 716 * snd_interval_div - refine the interval value with division
 717 * @a: dividend
 718 * @b: divisor
 719 * @c: quotient
 720 *
 721 * c = a / b
 722 *
 723 * Returns non-zero if the value is changed, zero if not changed.
 724 */
 725void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c)
 726{
 727        unsigned int r;
 728        if (a->empty || b->empty) {
 729                snd_interval_none(c);
 730                return;
 731        }
 732        c->empty = 0;
 733        c->min = div32(a->min, b->max, &r);
 734        c->openmin = (r || a->openmin || b->openmax);
 735        if (b->min > 0) {
 736                c->max = div32(a->max, b->min, &r);
 737                if (r) {
 738                        c->max++;
 739                        c->openmax = 1;
 740                } else
 741                        c->openmax = (a->openmax || b->openmin);
 742        } else {
 743                c->max = UINT_MAX;
 744                c->openmax = 0;
 745        }
 746        c->integer = 0;
 747}
 748
 749/**
 750 * snd_interval_muldivk - refine the interval value
 751 * @a: dividend 1
 752 * @b: dividend 2
 753 * @k: divisor (as integer)
 754 * @c: result
 755  *
 756 * c = a * b / k
 757 *
 758 * Returns non-zero if the value is changed, zero if not changed.
 759 */
 760void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b,
 761                      unsigned int k, struct snd_interval *c)
 762{
 763        unsigned int r;
 764        if (a->empty || b->empty) {
 765                snd_interval_none(c);
 766                return;
 767        }
 768        c->empty = 0;
 769        c->min = muldiv32(a->min, b->min, k, &r);
 770        c->openmin = (r || a->openmin || b->openmin);
 771        c->max = muldiv32(a->max, b->max, k, &r);
 772        if (r) {
 773                c->max++;
 774                c->openmax = 1;
 775        } else
 776                c->openmax = (a->openmax || b->openmax);
 777        c->integer = 0;
 778}
 779
 780/**
 781 * snd_interval_mulkdiv - refine the interval value
 782 * @a: dividend 1
 783 * @k: dividend 2 (as integer)
 784 * @b: divisor
 785 * @c: result
 786 *
 787 * c = a * k / b
 788 *
 789 * Returns non-zero if the value is changed, zero if not changed.
 790 */
 791void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
 792                      const struct snd_interval *b, struct snd_interval *c)
 793{
 794        unsigned int r;
 795        if (a->empty || b->empty) {
 796                snd_interval_none(c);
 797                return;
 798        }
 799        c->empty = 0;
 800        c->min = muldiv32(a->min, k, b->max, &r);
 801        c->openmin = (r || a->openmin || b->openmax);
 802        if (b->min > 0) {
 803                c->max = muldiv32(a->max, k, b->min, &r);
 804                if (r) {
 805                        c->max++;
 806                        c->openmax = 1;
 807                } else
 808                        c->openmax = (a->openmax || b->openmin);
 809        } else {
 810                c->max = UINT_MAX;
 811                c->openmax = 0;
 812        }
 813        c->integer = 0;
 814}
 815
 816/* ---- */
 817
 818
 819/**
 820 * snd_interval_ratnum - refine the interval value
 821 * @i: interval to refine
 822 * @rats_count: number of ratnum_t 
 823 * @rats: ratnum_t array
 824 * @nump: pointer to store the resultant numerator
 825 * @denp: pointer to store the resultant denominator
 826 *
 827 * Returns non-zero if the value is changed, zero if not changed.
 828 */
 829int snd_interval_ratnum(struct snd_interval *i,
 830                        unsigned int rats_count, struct snd_ratnum *rats,
 831                        unsigned int *nump, unsigned int *denp)
 832{
 833        unsigned int best_num, best_den;
 834        int best_diff;
 835        unsigned int k;
 836        struct snd_interval t;
 837        int err;
 838        unsigned int result_num, result_den;
 839        int result_diff;
 840
 841        best_num = best_den = best_diff = 0;
 842        for (k = 0; k < rats_count; ++k) {
 843                unsigned int num = rats[k].num;
 844                unsigned int den;
 845                unsigned int q = i->min;
 846                int diff;
 847                if (q == 0)
 848                        q = 1;
 849                den = div_up(num, q);
 850                if (den < rats[k].den_min)
 851                        continue;
 852                if (den > rats[k].den_max)
 853                        den = rats[k].den_max;
 854                else {
 855                        unsigned int r;
 856                        r = (den - rats[k].den_min) % rats[k].den_step;
 857                        if (r != 0)
 858                                den -= r;
 859                }
 860                diff = num - q * den;
 861                if (diff < 0)
 862                        diff = -diff;
 863                if (best_num == 0 ||
 864                    diff * best_den < best_diff * den) {
 865                        best_diff = diff;
 866                        best_den = den;
 867                        best_num = num;
 868                }
 869        }
 870        if (best_den == 0) {
 871                i->empty = 1;
 872                return -EINVAL;
 873        }
 874        t.min = div_down(best_num, best_den);
 875        t.openmin = !!(best_num % best_den);
 876        
 877        result_num = best_num;
 878        result_diff = best_diff;
 879        result_den = best_den;
 880        best_num = best_den = best_diff = 0;
 881        for (k = 0; k < rats_count; ++k) {
 882                unsigned int num = rats[k].num;
 883                unsigned int den;
 884                unsigned int q = i->max;
 885                int diff;
 886                if (q == 0) {
 887                        i->empty = 1;
 888                        return -EINVAL;
 889                }
 890                den = div_down(num, q);
 891                if (den > rats[k].den_max)
 892                        continue;
 893                if (den < rats[k].den_min)
 894                        den = rats[k].den_min;
 895                else {
 896                        unsigned int r;
 897                        r = (den - rats[k].den_min) % rats[k].den_step;
 898                        if (r != 0)
 899                                den += rats[k].den_step - r;
 900                }
 901                diff = q * den - num;
 902                if (diff < 0)
 903                        diff = -diff;
 904                if (best_num == 0 ||
 905                    diff * best_den < best_diff * den) {
 906                        best_diff = diff;
 907                        best_den = den;
 908                        best_num = num;
 909                }
 910        }
 911        if (best_den == 0) {
 912                i->empty = 1;
 913                return -EINVAL;
 914        }
 915        t.max = div_up(best_num, best_den);
 916        t.openmax = !!(best_num % best_den);
 917        t.integer = 0;
 918        err = snd_interval_refine(i, &t);
 919        if (err < 0)
 920                return err;
 921
 922        if (snd_interval_single(i)) {
 923                if (best_diff * result_den < result_diff * best_den) {
 924                        result_num = best_num;
 925                        result_den = best_den;
 926                }
 927                if (nump)
 928                        *nump = result_num;
 929                if (denp)
 930                        *denp = result_den;
 931        }
 932        return err;
 933}
 934
 935EXPORT_SYMBOL(snd_interval_ratnum);
 936
 937/**
 938 * snd_interval_ratden - refine the interval value
 939 * @i: interval to refine
 940 * @rats_count: number of struct ratden
 941 * @rats: struct ratden array
 942 * @nump: pointer to store the resultant numerator
 943 * @denp: pointer to store the resultant denominator
 944 *
 945 * Returns non-zero if the value is changed, zero if not changed.
 946 */
 947static int snd_interval_ratden(struct snd_interval *i,
 948                               unsigned int rats_count, struct snd_ratden *rats,
 949                               unsigned int *nump, unsigned int *denp)
 950{
 951        unsigned int best_num, best_diff, best_den;
 952        unsigned int k;
 953        struct snd_interval t;
 954        int err;
 955
 956        best_num = best_den = best_diff = 0;
 957        for (k = 0; k < rats_count; ++k) {
 958                unsigned int num;
 959                unsigned int den = rats[k].den;
 960                unsigned int q = i->min;
 961                int diff;
 962                num = mul(q, den);
 963                if (num > rats[k].num_max)
 964                        continue;
 965                if (num < rats[k].num_min)
 966                        num = rats[k].num_max;
 967                else {
 968                        unsigned int r;
 969                        r = (num - rats[k].num_min) % rats[k].num_step;
 970                        if (r != 0)
 971                                num += rats[k].num_step - r;
 972                }
 973                diff = num - q * den;
 974                if (best_num == 0 ||
 975                    diff * best_den < best_diff * den) {
 976                        best_diff = diff;
 977                        best_den = den;
 978                        best_num = num;
 979                }
 980        }
 981        if (best_den == 0) {
 982                i->empty = 1;
 983                return -EINVAL;
 984        }
 985        t.min = div_down(best_num, best_den);
 986        t.openmin = !!(best_num % best_den);
 987        
 988        best_num = best_den = best_diff = 0;
 989        for (k = 0; k < rats_count; ++k) {
 990                unsigned int num;
 991                unsigned int den = rats[k].den;
 992                unsigned int q = i->max;
 993                int diff;
 994                num = mul(q, den);
 995                if (num < rats[k].num_min)
 996                        continue;
 997                if (num > rats[k].num_max)
 998                        num = rats[k].num_max;
 999                else {
1000                        unsigned int r;
1001                        r = (num - rats[k].num_min) % rats[k].num_step;
1002                        if (r != 0)
1003                                num -= r;
1004                }
1005                diff = q * den - num;
1006                if (best_num == 0 ||
1007                    diff * best_den < best_diff * den) {
1008                        best_diff = diff;
1009                        best_den = den;
1010                        best_num = num;
1011                }
1012        }
1013        if (best_den == 0) {
1014                i->empty = 1;
1015                return -EINVAL;
1016        }
1017        t.max = div_up(best_num, best_den);
1018        t.openmax = !!(best_num % best_den);
1019        t.integer = 0;
1020        err = snd_interval_refine(i, &t);
1021        if (err < 0)
1022                return err;
1023
1024        if (snd_interval_single(i)) {
1025                if (nump)
1026                        *nump = best_num;
1027                if (denp)
1028                        *denp = best_den;
1029        }
1030        return err;
1031}
1032
1033/**
1034 * snd_interval_list - refine the interval value from the list
1035 * @i: the interval value to refine
1036 * @count: the number of elements in the list
1037 * @list: the value list
1038 * @mask: the bit-mask to evaluate
1039 *
1040 * Refines the interval value from the list.
1041 * When mask is non-zero, only the elements corresponding to bit 1 are
1042 * evaluated.
1043 *
1044 * Returns non-zero if the value is changed, zero if not changed.
1045 */
1046int snd_interval_list(struct snd_interval *i, unsigned int count,
1047                      const unsigned int *list, unsigned int mask)
1048{
1049        unsigned int k;
1050        struct snd_interval list_range;
1051
1052        if (!count) {
1053                i->empty = 1;
1054                return -EINVAL;
1055        }
1056        snd_interval_any(&list_range);
1057        list_range.min = UINT_MAX;
1058        list_range.max = 0;
1059        for (k = 0; k < count; k++) {
1060                if (mask && !(mask & (1 << k)))
1061                        continue;
1062                if (!snd_interval_test(i, list[k]))
1063                        continue;
1064                list_range.min = min(list_range.min, list[k]);
1065                list_range.max = max(list_range.max, list[k]);
1066        }
1067        return snd_interval_refine(i, &list_range);
1068}
1069
1070EXPORT_SYMBOL(snd_interval_list);
1071
1072static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
1073{
1074        unsigned int n;
1075        int changed = 0;
1076        n = (i->min - min) % step;
1077        if (n != 0 || i->openmin) {
1078                i->min += step - n;
1079                changed = 1;
1080        }
1081        n = (i->max - min) % step;
1082        if (n != 0 || i->openmax) {
1083                i->max -= n;
1084                changed = 1;
1085        }
1086        if (snd_interval_checkempty(i)) {
1087                i->empty = 1;
1088                return -EINVAL;
1089        }
1090        return changed;
1091}
1092
1093/* Info constraints helpers */
1094
1095/**
1096 * snd_pcm_hw_rule_add - add the hw-constraint rule
1097 * @runtime: the pcm runtime instance
1098 * @cond: condition bits
1099 * @var: the variable to evaluate
1100 * @func: the evaluation function
1101 * @private: the private data pointer passed to function
1102 * @dep: the dependent variables
1103 *
1104 * Returns zero if successful, or a negative error code on failure.
1105 */
1106int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime, unsigned int cond,
1107                        int var,
1108                        snd_pcm_hw_rule_func_t func, void *private,
1109                        int dep, ...)
1110{
1111        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1112        struct snd_pcm_hw_rule *c;
1113        unsigned int k;
1114        va_list args;
1115        va_start(args, dep);
1116        if (constrs->rules_num >= constrs->rules_all) {
1117                struct snd_pcm_hw_rule *new;
1118                unsigned int new_rules = constrs->rules_all + 16;
1119                new = kcalloc(new_rules, sizeof(*c), GFP_KERNEL);
1120                if (!new) {
1121                        va_end(args);
1122                        return -ENOMEM;
1123                }
1124                if (constrs->rules) {
1125                        memcpy(new, constrs->rules,
1126                               constrs->rules_num * sizeof(*c));
1127                        kfree(constrs->rules);
1128                }
1129                constrs->rules = new;
1130                constrs->rules_all = new_rules;
1131        }
1132        c = &constrs->rules[constrs->rules_num];
1133        c->cond = cond;
1134        c->func = func;
1135        c->var = var;
1136        c->private = private;
1137        k = 0;
1138        while (1) {
1139                if (snd_BUG_ON(k >= ARRAY_SIZE(c->deps))) {
1140                        va_end(args);
1141                        return -EINVAL;
1142                }
1143                c->deps[k++] = dep;
1144                if (dep < 0)
1145                        break;
1146                dep = va_arg(args, int);
1147        }
1148        constrs->rules_num++;
1149        va_end(args);
1150        return 0;
1151}
1152
1153EXPORT_SYMBOL(snd_pcm_hw_rule_add);
1154
1155/**
1156 * snd_pcm_hw_constraint_mask - apply the given bitmap mask constraint
1157 * @runtime: PCM runtime instance
1158 * @var: hw_params variable to apply the mask
1159 * @mask: the bitmap mask
1160 *
1161 * Apply the constraint of the given bitmap mask to a 32-bit mask parameter.
1162 */
1163int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1164                               u_int32_t mask)
1165{
1166        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1167        struct snd_mask *maskp = constrs_mask(constrs, var);
1168        *maskp->bits &= mask;
1169        memset(maskp->bits + 1, 0, (SNDRV_MASK_MAX-32) / 8); /* clear rest */
1170        if (*maskp->bits == 0)
1171                return -EINVAL;
1172        return 0;
1173}
1174
1175/**
1176 * snd_pcm_hw_constraint_mask64 - apply the given bitmap mask constraint
1177 * @runtime: PCM runtime instance
1178 * @var: hw_params variable to apply the mask
1179 * @mask: the 64bit bitmap mask
1180 *
1181 * Apply the constraint of the given bitmap mask to a 64-bit mask parameter.
1182 */
1183int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1184                                 u_int64_t mask)
1185{
1186        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1187        struct snd_mask *maskp = constrs_mask(constrs, var);
1188        maskp->bits[0] &= (u_int32_t)mask;
1189        maskp->bits[1] &= (u_int32_t)(mask >> 32);
1190        memset(maskp->bits + 2, 0, (SNDRV_MASK_MAX-64) / 8); /* clear rest */
1191        if (! maskp->bits[0] && ! maskp->bits[1])
1192                return -EINVAL;
1193        return 0;
1194}
1195
1196/**
1197 * snd_pcm_hw_constraint_integer - apply an integer constraint to an interval
1198 * @runtime: PCM runtime instance
1199 * @var: hw_params variable to apply the integer constraint
1200 *
1201 * Apply the constraint of integer to an interval parameter.
1202 */
1203int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var)
1204{
1205        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1206        return snd_interval_setinteger(constrs_interval(constrs, var));
1207}
1208
1209EXPORT_SYMBOL(snd_pcm_hw_constraint_integer);
1210
1211/**
1212 * snd_pcm_hw_constraint_minmax - apply a min/max range constraint to an interval
1213 * @runtime: PCM runtime instance
1214 * @var: hw_params variable to apply the range
1215 * @min: the minimal value
1216 * @max: the maximal value
1217 * 
1218 * Apply the min/max range constraint to an interval parameter.
1219 */
1220int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
1221                                 unsigned int min, unsigned int max)
1222{
1223        struct snd_pcm_hw_constraints *constrs = &runtime->hw_constraints;
1224        struct snd_interval t;
1225        t.min = min;
1226        t.max = max;
1227        t.openmin = t.openmax = 0;
1228        t.integer = 0;
1229        return snd_interval_refine(constrs_interval(constrs, var), &t);
1230}
1231
1232EXPORT_SYMBOL(snd_pcm_hw_constraint_minmax);
1233
1234static int snd_pcm_hw_rule_list(struct snd_pcm_hw_params *params,
1235                                struct snd_pcm_hw_rule *rule)
1236{
1237        struct snd_pcm_hw_constraint_list *list = rule->private;
1238        return snd_interval_list(hw_param_interval(params, rule->var), list->count, list->list, list->mask);
1239}               
1240
1241
1242/**
1243 * snd_pcm_hw_constraint_list - apply a list of constraints to a parameter
1244 * @runtime: PCM runtime instance
1245 * @cond: condition bits
1246 * @var: hw_params variable to apply the list constraint
1247 * @l: list
1248 * 
1249 * Apply the list of constraints to an interval parameter.
1250 */
1251int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime,
1252                               unsigned int cond,
1253                               snd_pcm_hw_param_t var,
1254                               const struct snd_pcm_hw_constraint_list *l)
1255{
1256        return snd_pcm_hw_rule_add(runtime, cond, var,
1257                                   snd_pcm_hw_rule_list, (void *)l,
1258                                   var, -1);
1259}
1260
1261EXPORT_SYMBOL(snd_pcm_hw_constraint_list);
1262
1263static int snd_pcm_hw_rule_ratnums(struct snd_pcm_hw_params *params,
1264                                   struct snd_pcm_hw_rule *rule)
1265{
1266        struct snd_pcm_hw_constraint_ratnums *r = rule->private;
1267        unsigned int num = 0, den = 0;
1268        int err;
1269        err = snd_interval_ratnum(hw_param_interval(params, rule->var),
1270                                  r->nrats, r->rats, &num, &den);
1271        if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1272                params->rate_num = num;
1273                params->rate_den = den;
1274        }
1275        return err;
1276}
1277
1278/**
1279 * snd_pcm_hw_constraint_ratnums - apply ratnums constraint to a parameter
1280 * @runtime: PCM runtime instance
1281 * @cond: condition bits
1282 * @var: hw_params variable to apply the ratnums constraint
1283 * @r: struct snd_ratnums constriants
1284 */
1285int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime, 
1286                                  unsigned int cond,
1287                                  snd_pcm_hw_param_t var,
1288                                  struct snd_pcm_hw_constraint_ratnums *r)
1289{
1290        return snd_pcm_hw_rule_add(runtime, cond, var,
1291                                   snd_pcm_hw_rule_ratnums, r,
1292                                   var, -1);
1293}
1294
1295EXPORT_SYMBOL(snd_pcm_hw_constraint_ratnums);
1296
1297static int snd_pcm_hw_rule_ratdens(struct snd_pcm_hw_params *params,
1298                                   struct snd_pcm_hw_rule *rule)
1299{
1300        struct snd_pcm_hw_constraint_ratdens *r = rule->private;
1301        unsigned int num = 0, den = 0;
1302        int err = snd_interval_ratden(hw_param_interval(params, rule->var),
1303                                  r->nrats, r->rats, &num, &den);
1304        if (err >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
1305                params->rate_num = num;
1306                params->rate_den = den;
1307        }
1308        return err;
1309}
1310
1311/**
1312 * snd_pcm_hw_constraint_ratdens - apply ratdens constraint to a parameter
1313 * @runtime: PCM runtime instance
1314 * @cond: condition bits
1315 * @var: hw_params variable to apply the ratdens constraint
1316 * @r: struct snd_ratdens constriants
1317 */
1318int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime, 
1319                                  unsigned int cond,
1320                                  snd_pcm_hw_param_t var,
1321                                  struct snd_pcm_hw_constraint_ratdens *r)
1322{
1323        return snd_pcm_hw_rule_add(runtime, cond, var,
1324                                   snd_pcm_hw_rule_ratdens, r,
1325                                   var, -1);
1326}
1327
1328EXPORT_SYMBOL(snd_pcm_hw_constraint_ratdens);
1329
1330static int snd_pcm_hw_rule_msbits(struct snd_pcm_hw_params *params,
1331                                  struct snd_pcm_hw_rule *rule)
1332{
1333        unsigned int l = (unsigned long) rule->private;
1334        int width = l & 0xffff;
1335        unsigned int msbits = l >> 16;
1336        struct snd_interval *i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
1337        if (snd_interval_single(i) && snd_interval_value(i) == width)
1338                params->msbits = msbits;
1339        return 0;
1340}
1341
1342/**
1343 * snd_pcm_hw_constraint_msbits - add a hw constraint msbits rule
1344 * @runtime: PCM runtime instance
1345 * @cond: condition bits
1346 * @width: sample bits width
1347 * @msbits: msbits width
1348 */
1349int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime, 
1350                                 unsigned int cond,
1351                                 unsigned int width,
1352                                 unsigned int msbits)
1353{
1354        unsigned long l = (msbits << 16) | width;
1355        return snd_pcm_hw_rule_add(runtime, cond, -1,
1356                                    snd_pcm_hw_rule_msbits,
1357                                    (void*) l,
1358                                    SNDRV_PCM_HW_PARAM_SAMPLE_BITS, -1);
1359}
1360
1361EXPORT_SYMBOL(snd_pcm_hw_constraint_msbits);
1362
1363static int snd_pcm_hw_rule_step(struct snd_pcm_hw_params *params,
1364                                struct snd_pcm_hw_rule *rule)
1365{
1366        unsigned long step = (unsigned long) rule->private;
1367        return snd_interval_step(hw_param_interval(params, rule->var), 0, step);
1368}
1369
1370/**
1371 * snd_pcm_hw_constraint_step - add a hw constraint step rule
1372 * @runtime: PCM runtime instance
1373 * @cond: condition bits
1374 * @var: hw_params variable to apply the step constraint
1375 * @step: step size
1376 */
1377int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
1378                               unsigned int cond,
1379                               snd_pcm_hw_param_t var,
1380                               unsigned long step)
1381{
1382        return snd_pcm_hw_rule_add(runtime, cond, var, 
1383                                   snd_pcm_hw_rule_step, (void *) step,
1384                                   var, -1);
1385}
1386
1387EXPORT_SYMBOL(snd_pcm_hw_constraint_step);
1388
1389static int snd_pcm_hw_rule_pow2(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
1390{
1391        static unsigned int pow2_sizes[] = {
1392                1<<0, 1<<1, 1<<2, 1<<3, 1<<4, 1<<5, 1<<6, 1<<7,
1393                1<<8, 1<<9, 1<<10, 1<<11, 1<<12, 1<<13, 1<<14, 1<<15,
1394                1<<16, 1<<17, 1<<18, 1<<19, 1<<20, 1<<21, 1<<22, 1<<23,
1395                1<<24, 1<<25, 1<<26, 1<<27, 1<<28, 1<<29, 1<<30
1396        };
1397        return snd_interval_list(hw_param_interval(params, rule->var),
1398                                 ARRAY_SIZE(pow2_sizes), pow2_sizes, 0);
1399}               
1400
1401/**
1402 * snd_pcm_hw_constraint_pow2 - add a hw constraint power-of-2 rule
1403 * @runtime: PCM runtime instance
1404 * @cond: condition bits
1405 * @var: hw_params variable to apply the power-of-2 constraint
1406 */
1407int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
1408                               unsigned int cond,
1409                               snd_pcm_hw_param_t var)
1410{
1411        return snd_pcm_hw_rule_add(runtime, cond, var, 
1412                                   snd_pcm_hw_rule_pow2, NULL,
1413                                   var, -1);
1414}
1415
1416EXPORT_SYMBOL(snd_pcm_hw_constraint_pow2);
1417
1418static int snd_pcm_hw_rule_noresample_func(struct snd_pcm_hw_params *params,
1419                                           struct snd_pcm_hw_rule *rule)
1420{
1421        unsigned int base_rate = (unsigned int)(uintptr_t)rule->private;
1422        struct snd_interval *rate;
1423
1424        rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
1425        return snd_interval_list(rate, 1, &base_rate, 0);
1426}
1427
1428/**
1429 * snd_pcm_hw_rule_noresample - add a rule to allow disabling hw resampling
1430 * @runtime: PCM runtime instance
1431 * @base_rate: the rate at which the hardware does not resample
1432 */
1433int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
1434                               unsigned int base_rate)
1435{
1436        return snd_pcm_hw_rule_add(runtime, SNDRV_PCM_HW_PARAMS_NORESAMPLE,
1437                                   SNDRV_PCM_HW_PARAM_RATE,
1438                                   snd_pcm_hw_rule_noresample_func,
1439                                   (void *)(uintptr_t)base_rate,
1440                                   SNDRV_PCM_HW_PARAM_RATE, -1);
1441}
1442EXPORT_SYMBOL(snd_pcm_hw_rule_noresample);
1443
1444static void _snd_pcm_hw_param_any(struct snd_pcm_hw_params *params,
1445                                  snd_pcm_hw_param_t var)
1446{
1447        if (hw_is_mask(var)) {
1448                snd_mask_any(hw_param_mask(params, var));
1449                params->cmask |= 1 << var;
1450                params->rmask |= 1 << var;
1451                return;
1452        }
1453        if (hw_is_interval(var)) {
1454                snd_interval_any(hw_param_interval(params, var));
1455                params->cmask |= 1 << var;
1456                params->rmask |= 1 << var;
1457                return;
1458        }
1459        snd_BUG();
1460}
1461
1462void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params)
1463{
1464        unsigned int k;
1465        memset(params, 0, sizeof(*params));
1466        for (k = SNDRV_PCM_HW_PARAM_FIRST_MASK; k <= SNDRV_PCM_HW_PARAM_LAST_MASK; k++)
1467                _snd_pcm_hw_param_any(params, k);
1468        for (k = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
1469                _snd_pcm_hw_param_any(params, k);
1470        params->info = ~0U;
1471}
1472
1473EXPORT_SYMBOL(_snd_pcm_hw_params_any);
1474
1475/**
1476 * snd_pcm_hw_param_value - return @params field @var value
1477 * @params: the hw_params instance
1478 * @var: parameter to retrieve
1479 * @dir: pointer to the direction (-1,0,1) or %NULL
1480 *
1481 * Return the value for field @var if it's fixed in configuration space
1482 * defined by @params. Return -%EINVAL otherwise.
1483 */
1484int snd_pcm_hw_param_value(const struct snd_pcm_hw_params *params,
1485                           snd_pcm_hw_param_t var, int *dir)
1486{
1487        if (hw_is_mask(var)) {
1488                const struct snd_mask *mask = hw_param_mask_c(params, var);
1489                if (!snd_mask_single(mask))
1490                        return -EINVAL;
1491                if (dir)
1492                        *dir = 0;
1493                return snd_mask_value(mask);
1494        }
1495        if (hw_is_interval(var)) {
1496                const struct snd_interval *i = hw_param_interval_c(params, var);
1497                if (!snd_interval_single(i))
1498                        return -EINVAL;
1499                if (dir)
1500                        *dir = i->openmin;
1501                return snd_interval_value(i);
1502        }
1503        return -EINVAL;
1504}
1505
1506EXPORT_SYMBOL(snd_pcm_hw_param_value);
1507
1508void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params,
1509                                snd_pcm_hw_param_t var)
1510{
1511        if (hw_is_mask(var)) {
1512                snd_mask_none(hw_param_mask(params, var));
1513                params->cmask |= 1 << var;
1514                params->rmask |= 1 << var;
1515        } else if (hw_is_interval(var)) {
1516                snd_interval_none(hw_param_interval(params, var));
1517                params->cmask |= 1 << var;
1518                params->rmask |= 1 << var;
1519        } else {
1520                snd_BUG();
1521        }
1522}
1523
1524EXPORT_SYMBOL(_snd_pcm_hw_param_setempty);
1525
1526static int _snd_pcm_hw_param_first(struct snd_pcm_hw_params *params,
1527                                   snd_pcm_hw_param_t var)
1528{
1529        int changed;
1530        if (hw_is_mask(var))
1531                changed = snd_mask_refine_first(hw_param_mask(params, var));
1532        else if (hw_is_interval(var))
1533                changed = snd_interval_refine_first(hw_param_interval(params, var));
1534        else
1535                return -EINVAL;
1536        if (changed) {
1537                params->cmask |= 1 << var;
1538                params->rmask |= 1 << var;
1539        }
1540        return changed;
1541}
1542
1543
1544/**
1545 * snd_pcm_hw_param_first - refine config space and return minimum value
1546 * @pcm: PCM instance
1547 * @params: the hw_params instance
1548 * @var: parameter to retrieve
1549 * @dir: pointer to the direction (-1,0,1) or %NULL
1550 *
1551 * Inside configuration space defined by @params remove from @var all
1552 * values > minimum. Reduce configuration space accordingly.
1553 * Return the minimum.
1554 */
1555int snd_pcm_hw_param_first(struct snd_pcm_substream *pcm, 
1556                           struct snd_pcm_hw_params *params, 
1557                           snd_pcm_hw_param_t var, int *dir)
1558{
1559        int changed = _snd_pcm_hw_param_first(params, var);
1560        if (changed < 0)
1561                return changed;
1562        if (params->rmask) {
1563                int err = snd_pcm_hw_refine(pcm, params);
1564                if (snd_BUG_ON(err < 0))
1565                        return err;
1566        }
1567        return snd_pcm_hw_param_value(params, var, dir);
1568}
1569
1570EXPORT_SYMBOL(snd_pcm_hw_param_first);
1571
1572static int _snd_pcm_hw_param_last(struct snd_pcm_hw_params *params,
1573                                  snd_pcm_hw_param_t var)
1574{
1575        int changed;
1576        if (hw_is_mask(var))
1577                changed = snd_mask_refine_last(hw_param_mask(params, var));
1578        else if (hw_is_interval(var))
1579                changed = snd_interval_refine_last(hw_param_interval(params, var));
1580        else
1581                return -EINVAL;
1582        if (changed) {
1583                params->cmask |= 1 << var;
1584                params->rmask |= 1 << var;
1585        }
1586        return changed;
1587}
1588
1589
1590/**
1591 * snd_pcm_hw_param_last - refine config space and return maximum value
1592 * @pcm: PCM instance
1593 * @params: the hw_params instance
1594 * @var: parameter to retrieve
1595 * @dir: pointer to the direction (-1,0,1) or %NULL
1596 *
1597 * Inside configuration space defined by @params remove from @var all
1598 * values < maximum. Reduce configuration space accordingly.
1599 * Return the maximum.
1600 */
1601int snd_pcm_hw_param_last(struct snd_pcm_substream *pcm, 
1602                          struct snd_pcm_hw_params *params,
1603                          snd_pcm_hw_param_t var, int *dir)
1604{
1605        int changed = _snd_pcm_hw_param_last(params, var);
1606        if (changed < 0)
1607                return changed;
1608        if (params->rmask) {
1609                int err = snd_pcm_hw_refine(pcm, params);
1610                if (snd_BUG_ON(err < 0))
1611                        return err;
1612        }
1613        return snd_pcm_hw_param_value(params, var, dir);
1614}
1615
1616EXPORT_SYMBOL(snd_pcm_hw_param_last);
1617
1618/**
1619 * snd_pcm_hw_param_choose - choose a configuration defined by @params
1620 * @pcm: PCM instance
1621 * @params: the hw_params instance
1622 *
1623 * Choose one configuration from configuration space defined by @params.
1624 * The configuration chosen is that obtained fixing in this order:
1625 * first access, first format, first subformat, min channels,
1626 * min rate, min period time, max buffer size, min tick time
1627 */
1628int snd_pcm_hw_params_choose(struct snd_pcm_substream *pcm,
1629                             struct snd_pcm_hw_params *params)
1630{
1631        static int vars[] = {
1632                SNDRV_PCM_HW_PARAM_ACCESS,
1633                SNDRV_PCM_HW_PARAM_FORMAT,
1634                SNDRV_PCM_HW_PARAM_SUBFORMAT,
1635                SNDRV_PCM_HW_PARAM_CHANNELS,
1636                SNDRV_PCM_HW_PARAM_RATE,
1637                SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1638                SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
1639                SNDRV_PCM_HW_PARAM_TICK_TIME,
1640                -1
1641        };
1642        int err, *v;
1643
1644        for (v = vars; *v != -1; v++) {
1645                if (*v != SNDRV_PCM_HW_PARAM_BUFFER_SIZE)
1646                        err = snd_pcm_hw_param_first(pcm, params, *v, NULL);
1647                else
1648                        err = snd_pcm_hw_param_last(pcm, params, *v, NULL);
1649                if (snd_BUG_ON(err < 0))
1650                        return err;
1651        }
1652        return 0;
1653}
1654
1655static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream,
1656                                   void *arg)
1657{
1658        struct snd_pcm_runtime *runtime = substream->runtime;
1659        unsigned long flags;
1660        snd_pcm_stream_lock_irqsave(substream, flags);
1661        if (snd_pcm_running(substream) &&
1662            snd_pcm_update_hw_ptr(substream) >= 0)
1663                runtime->status->hw_ptr %= runtime->buffer_size;
1664        else
1665                runtime->status->hw_ptr = 0;
1666        snd_pcm_stream_unlock_irqrestore(substream, flags);
1667        return 0;
1668}
1669
1670static int snd_pcm_lib_ioctl_channel_info(struct snd_pcm_substream *substream,
1671                                          void *arg)
1672{
1673        struct snd_pcm_channel_info *info = arg;
1674        struct snd_pcm_runtime *runtime = substream->runtime;
1675        int width;
1676        if (!(runtime->info & SNDRV_PCM_INFO_MMAP)) {
1677                info->offset = -1;
1678                return 0;
1679        }
1680        width = snd_pcm_format_physical_width(runtime->format);
1681        if (width < 0)
1682                return width;
1683        info->offset = 0;
1684        switch (runtime->access) {
1685        case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
1686        case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
1687                info->first = info->channel * width;
1688                info->step = runtime->channels * width;
1689                break;
1690        case SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED:
1691        case SNDRV_PCM_ACCESS_RW_NONINTERLEAVED:
1692        {
1693                size_t size = runtime->dma_bytes / runtime->channels;
1694                info->first = info->channel * size * 8;
1695                info->step = width;
1696                break;
1697        }
1698        default:
1699                snd_BUG();
1700                break;
1701        }
1702        return 0;
1703}
1704
1705static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream,
1706                                       void *arg)
1707{
1708        struct snd_pcm_hw_params *params = arg;
1709        snd_pcm_format_t format;
1710        int channels, width;
1711
1712        params->fifo_size = substream->runtime->hw.fifo_size;
1713        if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_FIFO_IN_FRAMES)) {
1714                format = params_format(params);
1715                channels = params_channels(params);
1716                width = snd_pcm_format_physical_width(format);
1717                params->fifo_size /= width * channels;
1718        }
1719        return 0;
1720}
1721
1722/**
1723 * snd_pcm_lib_ioctl - a generic PCM ioctl callback
1724 * @substream: the pcm substream instance
1725 * @cmd: ioctl command
1726 * @arg: ioctl argument
1727 *
1728 * Processes the generic ioctl commands for PCM.
1729 * Can be passed as the ioctl callback for PCM ops.
1730 *
1731 * Returns zero if successful, or a negative error code on failure.
1732 */
1733int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
1734                      unsigned int cmd, void *arg)
1735{
1736        switch (cmd) {
1737        case SNDRV_PCM_IOCTL1_INFO:
1738                return 0;
1739        case SNDRV_PCM_IOCTL1_RESET:
1740                return snd_pcm_lib_ioctl_reset(substream, arg);
1741        case SNDRV_PCM_IOCTL1_CHANNEL_INFO:
1742                return snd_pcm_lib_ioctl_channel_info(substream, arg);
1743        case SNDRV_PCM_IOCTL1_FIFO_SIZE:
1744                return snd_pcm_lib_ioctl_fifo_size(substream, arg);
1745        }
1746        return -ENXIO;
1747}
1748
1749EXPORT_SYMBOL(snd_pcm_lib_ioctl);
1750
1751/**
1752 * snd_pcm_period_elapsed - update the pcm status for the next period
1753 * @substream: the pcm substream instance
1754 *
1755 * This function is called from the interrupt handler when the
1756 * PCM has processed the period size.  It will update the current
1757 * pointer, wake up sleepers, etc.
1758 *
1759 * Even if more than one periods have elapsed since the last call, you
1760 * have to call this only once.
1761 */
1762void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
1763{
1764        struct snd_pcm_runtime *runtime;
1765        unsigned long flags;
1766
1767        if (PCM_RUNTIME_CHECK(substream))
1768                return;
1769        runtime = substream->runtime;
1770
1771        if (runtime->transfer_ack_begin)
1772                runtime->transfer_ack_begin(substream);
1773
1774        snd_pcm_stream_lock_irqsave(substream, flags);
1775        if (!snd_pcm_running(substream) ||
1776            snd_pcm_update_hw_ptr0(substream, 1) < 0)
1777                goto _end;
1778
1779        if (substream->timer_running)
1780                snd_timer_interrupt(substream->timer, 1);
1781 _end:
1782        snd_pcm_stream_unlock_irqrestore(substream, flags);
1783        if (runtime->transfer_ack_end)
1784                runtime->transfer_ack_end(substream);
1785        kill_fasync(&runtime->fasync, SIGIO, POLL_IN);
1786}
1787
1788EXPORT_SYMBOL(snd_pcm_period_elapsed);
1789
1790/*
1791 * Wait until avail_min data becomes available
1792 * Returns a negative error code if any error occurs during operation.
1793 * The available space is stored on availp.  When err = 0 and avail = 0
1794 * on the capture stream, it indicates the stream is in DRAINING state.
1795 */
1796static int wait_for_avail(struct snd_pcm_substream *substream,
1797                              snd_pcm_uframes_t *availp)
1798{
1799        struct snd_pcm_runtime *runtime = substream->runtime;
1800        int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
1801        wait_queue_t wait;
1802        int err = 0;
1803        snd_pcm_uframes_t avail = 0;
1804        long wait_time, tout;
1805
1806        init_waitqueue_entry(&wait, current);
1807        set_current_state(TASK_INTERRUPTIBLE);
1808        add_wait_queue(&runtime->tsleep, &wait);
1809
1810        if (runtime->no_period_wakeup)
1811                wait_time = MAX_SCHEDULE_TIMEOUT;
1812        else {
1813                wait_time = 10;
1814                if (runtime->rate) {
1815                        long t = runtime->period_size * 2 / runtime->rate;
1816                        wait_time = max(t, wait_time);
1817                }
1818                wait_time = msecs_to_jiffies(wait_time * 1000);
1819        }
1820
1821        for (;;) {
1822                if (signal_pending(current)) {
1823                        err = -ERESTARTSYS;
1824                        break;
1825                }
1826
1827                /*
1828                 * We need to check if space became available already
1829                 * (and thus the wakeup happened already) first to close
1830                 * the race of space already having become available.
1831                 * This check must happen after been added to the waitqueue
1832                 * and having current state be INTERRUPTIBLE.
1833                 */
1834                if (is_playback)
1835                        avail = snd_pcm_playback_avail(runtime);
1836                else
1837                        avail = snd_pcm_capture_avail(runtime);
1838                if (avail >= runtime->twake)
1839                        break;
1840                snd_pcm_stream_unlock_irq(substream);
1841
1842                tout = schedule_timeout(wait_time);
1843
1844                snd_pcm_stream_lock_irq(substream);
1845                set_current_state(TASK_INTERRUPTIBLE);
1846                switch (runtime->status->state) {
1847                case SNDRV_PCM_STATE_SUSPENDED:
1848                        err = -ESTRPIPE;
1849                        goto _endloop;
1850                case SNDRV_PCM_STATE_XRUN:
1851                        err = -EPIPE;
1852                        goto _endloop;
1853                case SNDRV_PCM_STATE_DRAINING:
1854                        if (is_playback)
1855                                err = -EPIPE;
1856                        else 
1857                                avail = 0; /* indicate draining */
1858                        goto _endloop;
1859                case SNDRV_PCM_STATE_OPEN:
1860                case SNDRV_PCM_STATE_SETUP:
1861                case SNDRV_PCM_STATE_DISCONNECTED:
1862                        err = -EBADFD;
1863                        goto _endloop;
1864                }
1865                if (!tout) {
1866                        snd_printd("%s write error (DMA or IRQ trouble?)\n",
1867                                   is_playback ? "playback" : "capture");
1868                        err = -EIO;
1869                        break;
1870                }
1871        }
1872 _endloop:
1873        set_current_state(TASK_RUNNING);
1874        remove_wait_queue(&runtime->tsleep, &wait);
1875        *availp = avail;
1876        return err;
1877}
1878        
1879static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream,
1880                                      unsigned int hwoff,
1881                                      unsigned long data, unsigned int off,
1882                                      snd_pcm_uframes_t frames)
1883{
1884        struct snd_pcm_runtime *runtime = substream->runtime;
1885        int err;
1886        char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
1887        if (substream->ops->copy) {
1888                if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
1889                        return err;
1890        } else {
1891                char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
1892                if (copy_from_user(hwbuf, buf, frames_to_bytes(runtime, frames)))
1893                        return -EFAULT;
1894        }
1895        return 0;
1896}
1897 
1898typedef int (*transfer_f)(struct snd_pcm_substream *substream, unsigned int hwoff,
1899                          unsigned long data, unsigned int off,
1900                          snd_pcm_uframes_t size);
1901
1902static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream, 
1903                                            unsigned long data,
1904                                            snd_pcm_uframes_t size,
1905                                            int nonblock,
1906                                            transfer_f transfer)
1907{
1908        struct snd_pcm_runtime *runtime = substream->runtime;
1909        snd_pcm_uframes_t xfer = 0;
1910        snd_pcm_uframes_t offset = 0;
1911        snd_pcm_uframes_t avail;
1912        int err = 0;
1913
1914        if (size == 0)
1915                return 0;
1916
1917        snd_pcm_stream_lock_irq(substream);
1918        switch (runtime->status->state) {
1919        case SNDRV_PCM_STATE_PREPARED:
1920        case SNDRV_PCM_STATE_RUNNING:
1921        case SNDRV_PCM_STATE_PAUSED:
1922                break;
1923        case SNDRV_PCM_STATE_XRUN:
1924                err = -EPIPE;
1925                goto _end_unlock;
1926        case SNDRV_PCM_STATE_SUSPENDED:
1927                err = -ESTRPIPE;
1928                goto _end_unlock;
1929        default:
1930                err = -EBADFD;
1931                goto _end_unlock;
1932        }
1933
1934        runtime->twake = runtime->control->avail_min ? : 1;
1935        if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
1936                snd_pcm_update_hw_ptr(substream);
1937        avail = snd_pcm_playback_avail(runtime);
1938        while (size > 0) {
1939                snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
1940                snd_pcm_uframes_t cont;
1941                if (!avail) {
1942                        if (nonblock) {
1943                                err = -EAGAIN;
1944                                goto _end_unlock;
1945                        }
1946                        runtime->twake = min_t(snd_pcm_uframes_t, size,
1947                                        runtime->control->avail_min ? : 1);
1948                        err = wait_for_avail(substream, &avail);
1949                        if (err < 0)
1950                                goto _end_unlock;
1951                }
1952                frames = size > avail ? avail : size;
1953                cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
1954                if (frames > cont)
1955                        frames = cont;
1956                if (snd_BUG_ON(!frames)) {
1957                        runtime->twake = 0;
1958                        snd_pcm_stream_unlock_irq(substream);
1959                        return -EINVAL;
1960                }
1961                appl_ptr = runtime->control->appl_ptr;
1962                appl_ofs = appl_ptr % runtime->buffer_size;
1963                snd_pcm_stream_unlock_irq(substream);
1964                err = transfer(substream, appl_ofs, data, offset, frames);
1965                snd_pcm_stream_lock_irq(substream);
1966                if (err < 0)
1967                        goto _end_unlock;
1968                switch (runtime->status->state) {
1969                case SNDRV_PCM_STATE_XRUN:
1970                        err = -EPIPE;
1971                        goto _end_unlock;
1972                case SNDRV_PCM_STATE_SUSPENDED:
1973                        err = -ESTRPIPE;
1974                        goto _end_unlock;
1975                default:
1976                        break;
1977                }
1978                appl_ptr += frames;
1979                if (appl_ptr >= runtime->boundary)
1980                        appl_ptr -= runtime->boundary;
1981                runtime->control->appl_ptr = appl_ptr;
1982                if (substream->ops->ack)
1983                        substream->ops->ack(substream);
1984
1985                offset += frames;
1986                size -= frames;
1987                xfer += frames;
1988                avail -= frames;
1989                if (runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
1990                    snd_pcm_playback_hw_avail(runtime) >= (snd_pcm_sframes_t)runtime->start_threshold) {
1991                        err = snd_pcm_start(substream);
1992                        if (err < 0)
1993                                goto _end_unlock;
1994                }
1995        }
1996 _end_unlock:
1997        runtime->twake = 0;
1998        if (xfer > 0 && err >= 0)
1999                snd_pcm_update_state(substream, runtime);
2000        snd_pcm_stream_unlock_irq(substream);
2001        return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2002}
2003
2004/* sanity-check for read/write methods */
2005static int pcm_sanity_check(struct snd_pcm_substream *substream)
2006{
2007        struct snd_pcm_runtime *runtime;
2008        if (PCM_RUNTIME_CHECK(substream))
2009                return -ENXIO;
2010        runtime = substream->runtime;
2011        if (snd_BUG_ON(!substream->ops->copy && !runtime->dma_area))
2012                return -EINVAL;
2013        if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2014                return -EBADFD;
2015        return 0;
2016}
2017
2018snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream, const void __user *buf, snd_pcm_uframes_t size)
2019{
2020        struct snd_pcm_runtime *runtime;
2021        int nonblock;
2022        int err;
2023
2024        err = pcm_sanity_check(substream);
2025        if (err < 0)
2026                return err;
2027        runtime = substream->runtime;
2028        nonblock = !!(substream->f_flags & O_NONBLOCK);
2029
2030        if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
2031            runtime->channels > 1)
2032                return -EINVAL;
2033        return snd_pcm_lib_write1(substream, (unsigned long)buf, size, nonblock,
2034                                  snd_pcm_lib_write_transfer);
2035}
2036
2037EXPORT_SYMBOL(snd_pcm_lib_write);
2038
2039static int snd_pcm_lib_writev_transfer(struct snd_pcm_substream *substream,
2040                                       unsigned int hwoff,
2041                                       unsigned long data, unsigned int off,
2042                                       snd_pcm_uframes_t frames)
2043{
2044        struct snd_pcm_runtime *runtime = substream->runtime;
2045        int err;
2046        void __user **bufs = (void __user **)data;
2047        int channels = runtime->channels;
2048        int c;
2049        if (substream->ops->copy) {
2050                if (snd_BUG_ON(!substream->ops->silence))
2051                        return -EINVAL;
2052                for (c = 0; c < channels; ++c, ++bufs) {
2053                        if (*bufs == NULL) {
2054                                if ((err = substream->ops->silence(substream, c, hwoff, frames)) < 0)
2055                                        return err;
2056                        } else {
2057                                char __user *buf = *bufs + samples_to_bytes(runtime, off);
2058                                if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2059                                        return err;
2060                        }
2061                }
2062        } else {
2063                /* default transfer behaviour */
2064                size_t dma_csize = runtime->dma_bytes / channels;
2065                for (c = 0; c < channels; ++c, ++bufs) {
2066                        char *hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2067                        if (*bufs == NULL) {
2068                                snd_pcm_format_set_silence(runtime->format, hwbuf, frames);
2069                        } else {
2070                                char __user *buf = *bufs + samples_to_bytes(runtime, off);
2071                                if (copy_from_user(hwbuf, buf, samples_to_bytes(runtime, frames)))
2072                                        return -EFAULT;
2073                        }
2074                }
2075        }
2076        return 0;
2077}
2078 
2079snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
2080                                     void __user **bufs,
2081                                     snd_pcm_uframes_t frames)
2082{
2083        struct snd_pcm_runtime *runtime;
2084        int nonblock;
2085        int err;
2086
2087        err = pcm_sanity_check(substream);
2088        if (err < 0)
2089                return err;
2090        runtime = substream->runtime;
2091        nonblock = !!(substream->f_flags & O_NONBLOCK);
2092
2093        if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2094                return -EINVAL;
2095        return snd_pcm_lib_write1(substream, (unsigned long)bufs, frames,
2096                                  nonblock, snd_pcm_lib_writev_transfer);
2097}
2098
2099EXPORT_SYMBOL(snd_pcm_lib_writev);
2100
2101static int snd_pcm_lib_read_transfer(struct snd_pcm_substream *substream, 
2102                                     unsigned int hwoff,
2103                                     unsigned long data, unsigned int off,
2104                                     snd_pcm_uframes_t frames)
2105{
2106        struct snd_pcm_runtime *runtime = substream->runtime;
2107        int err;
2108        char __user *buf = (char __user *) data + frames_to_bytes(runtime, off);
2109        if (substream->ops->copy) {
2110                if ((err = substream->ops->copy(substream, -1, hwoff, buf, frames)) < 0)
2111                        return err;
2112        } else {
2113                char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
2114                if (copy_to_user(buf, hwbuf, frames_to_bytes(runtime, frames)))
2115                        return -EFAULT;
2116        }
2117        return 0;
2118}
2119
2120static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream,
2121                                           unsigned long data,
2122                                           snd_pcm_uframes_t size,
2123                                           int nonblock,
2124                                           transfer_f transfer)
2125{
2126        struct snd_pcm_runtime *runtime = substream->runtime;
2127        snd_pcm_uframes_t xfer = 0;
2128        snd_pcm_uframes_t offset = 0;
2129        snd_pcm_uframes_t avail;
2130        int err = 0;
2131
2132        if (size == 0)
2133                return 0;
2134
2135        snd_pcm_stream_lock_irq(substream);
2136        switch (runtime->status->state) {
2137        case SNDRV_PCM_STATE_PREPARED:
2138                if (size >= runtime->start_threshold) {
2139                        err = snd_pcm_start(substream);
2140                        if (err < 0)
2141                                goto _end_unlock;
2142                }
2143                break;
2144        case SNDRV_PCM_STATE_DRAINING:
2145        case SNDRV_PCM_STATE_RUNNING:
2146        case SNDRV_PCM_STATE_PAUSED:
2147                break;
2148        case SNDRV_PCM_STATE_XRUN:
2149                err = -EPIPE;
2150                goto _end_unlock;
2151        case SNDRV_PCM_STATE_SUSPENDED:
2152                err = -ESTRPIPE;
2153                goto _end_unlock;
2154        default:
2155                err = -EBADFD;
2156                goto _end_unlock;
2157        }
2158
2159        runtime->twake = runtime->control->avail_min ? : 1;
2160        if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
2161                snd_pcm_update_hw_ptr(substream);
2162        avail = snd_pcm_capture_avail(runtime);
2163        while (size > 0) {
2164                snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
2165                snd_pcm_uframes_t cont;
2166                if (!avail) {
2167                        if (runtime->status->state ==
2168                            SNDRV_PCM_STATE_DRAINING) {
2169                                snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP);
2170                                goto _end_unlock;
2171                        }
2172                        if (nonblock) {
2173                                err = -EAGAIN;
2174                                goto _end_unlock;
2175                        }
2176                        runtime->twake = min_t(snd_pcm_uframes_t, size,
2177                                        runtime->control->avail_min ? : 1);
2178                        err = wait_for_avail(substream, &avail);
2179                        if (err < 0)
2180                                goto _end_unlock;
2181                        if (!avail)
2182                                continue; /* draining */
2183                }
2184                frames = size > avail ? avail : size;
2185                cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size;
2186                if (frames > cont)
2187                        frames = cont;
2188                if (snd_BUG_ON(!frames)) {
2189                        runtime->twake = 0;
2190                        snd_pcm_stream_unlock_irq(substream);
2191                        return -EINVAL;
2192                }
2193                appl_ptr = runtime->control->appl_ptr;
2194                appl_ofs = appl_ptr % runtime->buffer_size;
2195                snd_pcm_stream_unlock_irq(substream);
2196                err = transfer(substream, appl_ofs, data, offset, frames);
2197                snd_pcm_stream_lock_irq(substream);
2198                if (err < 0)
2199                        goto _end_unlock;
2200                switch (runtime->status->state) {
2201                case SNDRV_PCM_STATE_XRUN:
2202                        err = -EPIPE;
2203                        goto _end_unlock;
2204                case SNDRV_PCM_STATE_SUSPENDED:
2205                        err = -ESTRPIPE;
2206                        goto _end_unlock;
2207                default:
2208                        break;
2209                }
2210                appl_ptr += frames;
2211                if (appl_ptr >= runtime->boundary)
2212                        appl_ptr -= runtime->boundary;
2213                runtime->control->appl_ptr = appl_ptr;
2214                if (substream->ops->ack)
2215                        substream->ops->ack(substream);
2216
2217                offset += frames;
2218                size -= frames;
2219                xfer += frames;
2220                avail -= frames;
2221        }
2222 _end_unlock:
2223        runtime->twake = 0;
2224        if (xfer > 0 && err >= 0)
2225                snd_pcm_update_state(substream, runtime);
2226        snd_pcm_stream_unlock_irq(substream);
2227        return xfer > 0 ? (snd_pcm_sframes_t)xfer : err;
2228}
2229
2230snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream, void __user *buf, snd_pcm_uframes_t size)
2231{
2232        struct snd_pcm_runtime *runtime;
2233        int nonblock;
2234        int err;
2235        
2236        err = pcm_sanity_check(substream);
2237        if (err < 0)
2238                return err;
2239        runtime = substream->runtime;
2240        nonblock = !!(substream->f_flags & O_NONBLOCK);
2241        if (runtime->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED)
2242                return -EINVAL;
2243        return snd_pcm_lib_read1(substream, (unsigned long)buf, size, nonblock, snd_pcm_lib_read_transfer);
2244}
2245
2246EXPORT_SYMBOL(snd_pcm_lib_read);
2247
2248static int snd_pcm_lib_readv_transfer(struct snd_pcm_substream *substream,
2249                                      unsigned int hwoff,
2250                                      unsigned long data, unsigned int off,
2251                                      snd_pcm_uframes_t frames)
2252{
2253        struct snd_pcm_runtime *runtime = substream->runtime;
2254        int err;
2255        void __user **bufs = (void __user **)data;
2256        int channels = runtime->channels;
2257        int c;
2258        if (substream->ops->copy) {
2259                for (c = 0; c < channels; ++c, ++bufs) {
2260                        char __user *buf;
2261                        if (*bufs == NULL)
2262                                continue;
2263                        buf = *bufs + samples_to_bytes(runtime, off);
2264                        if ((err = substream->ops->copy(substream, c, hwoff, buf, frames)) < 0)
2265                                return err;
2266                }
2267        } else {
2268                snd_pcm_uframes_t dma_csize = runtime->dma_bytes / channels;
2269                for (c = 0; c < channels; ++c, ++bufs) {
2270                        char *hwbuf;
2271                        char __user *buf;
2272                        if (*bufs == NULL)
2273                                continue;
2274
2275                        hwbuf = runtime->dma_area + (c * dma_csize) + samples_to_bytes(runtime, hwoff);
2276                        buf = *bufs + samples_to_bytes(runtime, off);
2277                        if (copy_to_user(buf, hwbuf, samples_to_bytes(runtime, frames)))
2278                                return -EFAULT;
2279                }
2280        }
2281        return 0;
2282}
2283 
2284snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
2285                                    void __user **bufs,
2286                                    snd_pcm_uframes_t frames)
2287{
2288        struct snd_pcm_runtime *runtime;
2289        int nonblock;
2290        int err;
2291
2292        err = pcm_sanity_check(substream);
2293        if (err < 0)
2294                return err;
2295        runtime = substream->runtime;
2296        if (runtime->status->state == SNDRV_PCM_STATE_OPEN)
2297                return -EBADFD;
2298
2299        nonblock = !!(substream->f_flags & O_NONBLOCK);
2300        if (runtime->access != SNDRV_PCM_ACCESS_RW_NONINTERLEAVED)
2301                return -EINVAL;
2302        return snd_pcm_lib_read1(substream, (unsigned long)bufs, frames, nonblock, snd_pcm_lib_readv_transfer);
2303}
2304
2305EXPORT_SYMBOL(snd_pcm_lib_readv);
2306
2307/*
2308 * standard channel mapping helpers
2309 */
2310
2311/* default channel maps for multi-channel playbacks, up to 8 channels */
2312const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
2313        { .channels = 1,
2314          .map = { SNDRV_CHMAP_MONO } },
2315        { .channels = 2,
2316          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2317        { .channels = 4,
2318          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2319                   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2320        { .channels = 6,
2321          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2322                   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2323                   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
2324        { .channels = 8,
2325          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2326                   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2327                   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2328                   SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2329        { }
2330};
2331EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
2332
2333/* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
2334const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
2335        { .channels = 1,
2336          .map = { SNDRV_CHMAP_MONO } },
2337        { .channels = 2,
2338          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
2339        { .channels = 4,
2340          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2341                   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2342        { .channels = 6,
2343          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2344                   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2345                   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
2346        { .channels = 8,
2347          .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
2348                   SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
2349                   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
2350                   SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
2351        { }
2352};
2353EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
2354
2355static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
2356{
2357        if (ch > info->max_channels)
2358                return false;
2359        return !info->channel_mask || (info->channel_mask & (1U << ch));
2360}
2361
2362static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
2363                              struct snd_ctl_elem_info *uinfo)
2364{
2365        struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2366
2367        uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
2368        uinfo->count = 0;
2369        uinfo->count = info->max_channels;
2370        uinfo->value.integer.min = 0;
2371        uinfo->value.integer.max = SNDRV_CHMAP_LAST;
2372        return 0;
2373}
2374
2375/* get callback for channel map ctl element
2376 * stores the channel position firstly matching with the current channels
2377 */
2378static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
2379                             struct snd_ctl_elem_value *ucontrol)
2380{
2381        struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2382        unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
2383        struct snd_pcm_substream *substream;
2384        const struct snd_pcm_chmap_elem *map;
2385
2386        if (snd_BUG_ON(!info->chmap))
2387                return -EINVAL;
2388        substream = snd_pcm_chmap_substream(info, idx);
2389        if (!substream)
2390                return -ENODEV;
2391        memset(ucontrol->value.integer.value, 0,
2392               sizeof(ucontrol->value.integer.value));
2393        if (!substream->runtime)
2394                return 0; /* no channels set */
2395        for (map = info->chmap; map->channels; map++) {
2396                int i;
2397                if (map->channels == substream->runtime->channels &&
2398                    valid_chmap_channels(info, map->channels)) {
2399                        for (i = 0; i < map->channels; i++)
2400                                ucontrol->value.integer.value[i] = map->map[i];
2401                        return 0;
2402                }
2403        }
2404        return -EINVAL;
2405}
2406
2407/* tlv callback for channel map ctl element
2408 * expands the pre-defined channel maps in a form of TLV
2409 */
2410static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
2411                             unsigned int size, unsigned int __user *tlv)
2412{
2413        struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2414        const struct snd_pcm_chmap_elem *map;
2415        unsigned int __user *dst;
2416        int c, count = 0;
2417
2418        if (snd_BUG_ON(!info->chmap))
2419                return -EINVAL;
2420        if (size < 8)
2421                return -ENOMEM;
2422        if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
2423                return -EFAULT;
2424        size -= 8;
2425        dst = tlv + 2;
2426        for (map = info->chmap; map->channels; map++) {
2427                int chs_bytes = map->channels * 4;
2428                if (!valid_chmap_channels(info, map->channels))
2429                        continue;
2430                if (size < 8)
2431                        return -ENOMEM;
2432                if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
2433                    put_user(chs_bytes, dst + 1))
2434                        return -EFAULT;
2435                dst += 2;
2436                size -= 8;
2437                count += 8;
2438                if (size < chs_bytes)
2439                        return -ENOMEM;
2440                size -= chs_bytes;
2441                count += chs_bytes;
2442                for (c = 0; c < map->channels; c++) {
2443                        if (put_user(map->map[c], dst))
2444                                return -EFAULT;
2445                        dst++;
2446                }
2447        }
2448        if (put_user(count, tlv + 1))
2449                return -EFAULT;
2450        return 0;
2451}
2452
2453static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
2454{
2455        struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
2456        info->pcm->streams[info->stream].chmap_kctl = NULL;
2457        kfree(info);
2458}
2459
2460/**
2461 * snd_pcm_add_chmap_ctls - create channel-mapping control elements
2462 * @pcm: the assigned PCM instance
2463 * @stream: stream direction
2464 * @chmap: channel map elements (for query)
2465 * @max_channels: the max number of channels for the stream
2466 * @private_value: the value passed to each kcontrol's private_value field
2467 * @info_ret: store struct snd_pcm_chmap instance if non-NULL
2468 *
2469 * Create channel-mapping control elements assigned to the given PCM stream(s).
2470 * Returns zero if succeed, or a negative error value.
2471 */
2472int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
2473                           const struct snd_pcm_chmap_elem *chmap,
2474                           int max_channels,
2475                           unsigned long private_value,
2476                           struct snd_pcm_chmap **info_ret)
2477{
2478        struct snd_pcm_chmap *info;
2479        struct snd_kcontrol_new knew = {
2480                .iface = SNDRV_CTL_ELEM_IFACE_PCM,
2481                .access = SNDRV_CTL_ELEM_ACCESS_READ |
2482                        SNDRV_CTL_ELEM_ACCESS_TLV_READ |
2483                        SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
2484                .info = pcm_chmap_ctl_info,
2485                .get = pcm_chmap_ctl_get,
2486                .tlv.c = pcm_chmap_ctl_tlv,
2487        };
2488        int err;
2489
2490        info = kzalloc(sizeof(*info), GFP_KERNEL);
2491        if (!info)
2492                return -ENOMEM;
2493        info->pcm = pcm;
2494        info->stream = stream;
2495        info->chmap = chmap;
2496        info->max_channels = max_channels;
2497        if (stream == SNDRV_PCM_STREAM_PLAYBACK)
2498                knew.name = "Playback Channel Map";
2499        else
2500                knew.name = "Capture Channel Map";
2501        knew.device = pcm->device;
2502        knew.count = pcm->streams[stream].substream_count;
2503        knew.private_value = private_value;
2504        info->kctl = snd_ctl_new1(&knew, info);
2505        if (!info->kctl) {
2506                kfree(info);
2507                return -ENOMEM;
2508        }
2509        info->kctl->private_free = pcm_chmap_ctl_private_free;
2510        err = snd_ctl_add(pcm->card, info->kctl);
2511        if (err < 0)
2512                return err;
2513        pcm->streams[stream].chmap_kctl = info->kctl;
2514        if (info_ret)
2515                *info_ret = info;
2516        return 0;
2517}
2518EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);
2519
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.