linux/sound/drivers/dummy.c
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   1/*
   2 *  Dummy soundcard
   3 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   4 *
   5 *   This program is free software; you can redistribute it and/or modify
   6 *   it under the terms of the GNU General Public License as published by
   7 *   the Free Software Foundation; either version 2 of the License, or
   8 *   (at your option) any later version.
   9 *
  10 *   This program is distributed in the hope that it will be useful,
  11 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 *   GNU General Public License for more details.
  14 *
  15 *   You should have received a copy of the GNU General Public License
  16 *   along with this program; if not, write to the Free Software
  17 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  18 *
  19 */
  20
  21#include <linux/init.h>
  22#include <linux/err.h>
  23#include <linux/platform_device.h>
  24#include <linux/jiffies.h>
  25#include <linux/slab.h>
  26#include <linux/time.h>
  27#include <linux/wait.h>
  28#include <linux/hrtimer.h>
  29#include <linux/math64.h>
  30#include <linux/module.h>
  31#include <sound/core.h>
  32#include <sound/control.h>
  33#include <sound/tlv.h>
  34#include <sound/pcm.h>
  35#include <sound/rawmidi.h>
  36#include <sound/info.h>
  37#include <sound/initval.h>
  38
  39MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
  40MODULE_DESCRIPTION("Dummy soundcard (/dev/null)");
  41MODULE_LICENSE("GPL");
  42MODULE_SUPPORTED_DEVICE("{{ALSA,Dummy soundcard}}");
  43
  44#define MAX_PCM_DEVICES         4
  45#define MAX_PCM_SUBSTREAMS      128
  46#define MAX_MIDI_DEVICES        2
  47
  48/* defaults */
  49#define MAX_BUFFER_SIZE         (64*1024)
  50#define MIN_PERIOD_SIZE         64
  51#define MAX_PERIOD_SIZE         MAX_BUFFER_SIZE
  52#define USE_FORMATS             (SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE)
  53#define USE_RATE                SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000
  54#define USE_RATE_MIN            5500
  55#define USE_RATE_MAX            48000
  56#define USE_CHANNELS_MIN        1
  57#define USE_CHANNELS_MAX        2
  58#define USE_PERIODS_MIN         1
  59#define USE_PERIODS_MAX         1024
  60
  61static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;      /* Index 0-MAX */
  62static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;       /* ID for this card */
  63static bool enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
  64static char *model[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = NULL};
  65static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
  66static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8};
  67//static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2};
  68#ifdef CONFIG_HIGH_RES_TIMERS
  69static bool hrtimer = 1;
  70#endif
  71static bool fake_buffer = 1;
  72
  73module_param_array(index, int, NULL, 0444);
  74MODULE_PARM_DESC(index, "Index value for dummy soundcard.");
  75module_param_array(id, charp, NULL, 0444);
  76MODULE_PARM_DESC(id, "ID string for dummy soundcard.");
  77module_param_array(enable, bool, NULL, 0444);
  78MODULE_PARM_DESC(enable, "Enable this dummy soundcard.");
  79module_param_array(model, charp, NULL, 0444);
  80MODULE_PARM_DESC(model, "Soundcard model.");
  81module_param_array(pcm_devs, int, NULL, 0444);
  82MODULE_PARM_DESC(pcm_devs, "PCM devices # (0-4) for dummy driver.");
  83module_param_array(pcm_substreams, int, NULL, 0444);
  84MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-128) for dummy driver.");
  85//module_param_array(midi_devs, int, NULL, 0444);
  86//MODULE_PARM_DESC(midi_devs, "MIDI devices # (0-2) for dummy driver.");
  87module_param(fake_buffer, bool, 0444);
  88MODULE_PARM_DESC(fake_buffer, "Fake buffer allocations.");
  89#ifdef CONFIG_HIGH_RES_TIMERS
  90module_param(hrtimer, bool, 0644);
  91MODULE_PARM_DESC(hrtimer, "Use hrtimer as the timer source.");
  92#endif
  93
  94static struct platform_device *devices[SNDRV_CARDS];
  95
  96#define MIXER_ADDR_MASTER       0
  97#define MIXER_ADDR_LINE         1
  98#define MIXER_ADDR_MIC          2
  99#define MIXER_ADDR_SYNTH        3
 100#define MIXER_ADDR_CD           4
 101#define MIXER_ADDR_LAST         4
 102
 103struct dummy_timer_ops {
 104        int (*create)(struct snd_pcm_substream *);
 105        void (*free)(struct snd_pcm_substream *);
 106        int (*prepare)(struct snd_pcm_substream *);
 107        int (*start)(struct snd_pcm_substream *);
 108        int (*stop)(struct snd_pcm_substream *);
 109        snd_pcm_uframes_t (*pointer)(struct snd_pcm_substream *);
 110};
 111
 112struct dummy_model {
 113        const char *name;
 114        int (*playback_constraints)(struct snd_pcm_runtime *runtime);
 115        int (*capture_constraints)(struct snd_pcm_runtime *runtime);
 116        u64 formats;
 117        size_t buffer_bytes_max;
 118        size_t period_bytes_min;
 119        size_t period_bytes_max;
 120        unsigned int periods_min;
 121        unsigned int periods_max;
 122        unsigned int rates;
 123        unsigned int rate_min;
 124        unsigned int rate_max;
 125        unsigned int channels_min;
 126        unsigned int channels_max;
 127};
 128
 129struct snd_dummy {
 130        struct snd_card *card;
 131        struct dummy_model *model;
 132        struct snd_pcm *pcm;
 133        struct snd_pcm_hardware pcm_hw;
 134        spinlock_t mixer_lock;
 135        int mixer_volume[MIXER_ADDR_LAST+1][2];
 136        int capture_source[MIXER_ADDR_LAST+1][2];
 137        const struct dummy_timer_ops *timer_ops;
 138};
 139
 140/*
 141 * card models
 142 */
 143
 144static int emu10k1_playback_constraints(struct snd_pcm_runtime *runtime)
 145{
 146        int err;
 147        err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 148        if (err < 0)
 149                return err;
 150        err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX);
 151        if (err < 0)
 152                return err;
 153        return 0;
 154}
 155
 156struct dummy_model model_emu10k1 = {
 157        .name = "emu10k1",
 158        .playback_constraints = emu10k1_playback_constraints,
 159        .buffer_bytes_max = 128 * 1024,
 160};
 161
 162struct dummy_model model_rme9652 = {
 163        .name = "rme9652",
 164        .buffer_bytes_max = 26 * 64 * 1024,
 165        .formats = SNDRV_PCM_FMTBIT_S32_LE,
 166        .channels_min = 26,
 167        .channels_max = 26,
 168        .periods_min = 2,
 169        .periods_max = 2,
 170};
 171
 172struct dummy_model model_ice1712 = {
 173        .name = "ice1712",
 174        .buffer_bytes_max = 256 * 1024,
 175        .formats = SNDRV_PCM_FMTBIT_S32_LE,
 176        .channels_min = 10,
 177        .channels_max = 10,
 178        .periods_min = 1,
 179        .periods_max = 1024,
 180};
 181
 182struct dummy_model model_uda1341 = {
 183        .name = "uda1341",
 184        .buffer_bytes_max = 16380,
 185        .formats = SNDRV_PCM_FMTBIT_S16_LE,
 186        .channels_min = 2,
 187        .channels_max = 2,
 188        .periods_min = 2,
 189        .periods_max = 255,
 190};
 191
 192struct dummy_model model_ac97 = {
 193        .name = "ac97",
 194        .formats = SNDRV_PCM_FMTBIT_S16_LE,
 195        .channels_min = 2,
 196        .channels_max = 2,
 197        .rates = SNDRV_PCM_RATE_48000,
 198        .rate_min = 48000,
 199        .rate_max = 48000,
 200};
 201
 202struct dummy_model model_ca0106 = {
 203        .name = "ca0106",
 204        .formats = SNDRV_PCM_FMTBIT_S16_LE,
 205        .buffer_bytes_max = ((65536-64)*8),
 206        .period_bytes_max = (65536-64),
 207        .periods_min = 2,
 208        .periods_max = 8,
 209        .channels_min = 2,
 210        .channels_max = 2,
 211        .rates = SNDRV_PCM_RATE_48000|SNDRV_PCM_RATE_96000|SNDRV_PCM_RATE_192000,
 212        .rate_min = 48000,
 213        .rate_max = 192000,
 214};
 215
 216struct dummy_model *dummy_models[] = {
 217        &model_emu10k1,
 218        &model_rme9652,
 219        &model_ice1712,
 220        &model_uda1341,
 221        &model_ac97,
 222        &model_ca0106,
 223        NULL
 224};
 225
 226/*
 227 * system timer interface
 228 */
 229
 230struct dummy_systimer_pcm {
 231        spinlock_t lock;
 232        struct timer_list timer;
 233        unsigned long base_time;
 234        unsigned int frac_pos;  /* fractional sample position (based HZ) */
 235        unsigned int frac_period_rest;
 236        unsigned int frac_buffer_size;  /* buffer_size * HZ */
 237        unsigned int frac_period_size;  /* period_size * HZ */
 238        unsigned int rate;
 239        int elapsed;
 240        struct snd_pcm_substream *substream;
 241};
 242
 243static void dummy_systimer_rearm(struct dummy_systimer_pcm *dpcm)
 244{
 245        dpcm->timer.expires = jiffies +
 246                (dpcm->frac_period_rest + dpcm->rate - 1) / dpcm->rate;
 247        add_timer(&dpcm->timer);
 248}
 249
 250static void dummy_systimer_update(struct dummy_systimer_pcm *dpcm)
 251{
 252        unsigned long delta;
 253
 254        delta = jiffies - dpcm->base_time;
 255        if (!delta)
 256                return;
 257        dpcm->base_time += delta;
 258        delta *= dpcm->rate;
 259        dpcm->frac_pos += delta;
 260        while (dpcm->frac_pos >= dpcm->frac_buffer_size)
 261                dpcm->frac_pos -= dpcm->frac_buffer_size;
 262        while (dpcm->frac_period_rest <= delta) {
 263                dpcm->elapsed++;
 264                dpcm->frac_period_rest += dpcm->frac_period_size;
 265        }
 266        dpcm->frac_period_rest -= delta;
 267}
 268
 269static int dummy_systimer_start(struct snd_pcm_substream *substream)
 270{
 271        struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 272        spin_lock(&dpcm->lock);
 273        dpcm->base_time = jiffies;
 274        dummy_systimer_rearm(dpcm);
 275        spin_unlock(&dpcm->lock);
 276        return 0;
 277}
 278
 279static int dummy_systimer_stop(struct snd_pcm_substream *substream)
 280{
 281        struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 282        spin_lock(&dpcm->lock);
 283        del_timer(&dpcm->timer);
 284        spin_unlock(&dpcm->lock);
 285        return 0;
 286}
 287
 288static int dummy_systimer_prepare(struct snd_pcm_substream *substream)
 289{
 290        struct snd_pcm_runtime *runtime = substream->runtime;
 291        struct dummy_systimer_pcm *dpcm = runtime->private_data;
 292
 293        dpcm->frac_pos = 0;
 294        dpcm->rate = runtime->rate;
 295        dpcm->frac_buffer_size = runtime->buffer_size * HZ;
 296        dpcm->frac_period_size = runtime->period_size * HZ;
 297        dpcm->frac_period_rest = dpcm->frac_period_size;
 298        dpcm->elapsed = 0;
 299
 300        return 0;
 301}
 302
 303static void dummy_systimer_callback(unsigned long data)
 304{
 305        struct dummy_systimer_pcm *dpcm = (struct dummy_systimer_pcm *)data;
 306        unsigned long flags;
 307        int elapsed = 0;
 308        
 309        spin_lock_irqsave(&dpcm->lock, flags);
 310        dummy_systimer_update(dpcm);
 311        dummy_systimer_rearm(dpcm);
 312        elapsed = dpcm->elapsed;
 313        dpcm->elapsed = 0;
 314        spin_unlock_irqrestore(&dpcm->lock, flags);
 315        if (elapsed)
 316                snd_pcm_period_elapsed(dpcm->substream);
 317}
 318
 319static snd_pcm_uframes_t
 320dummy_systimer_pointer(struct snd_pcm_substream *substream)
 321{
 322        struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 323        snd_pcm_uframes_t pos;
 324
 325        spin_lock(&dpcm->lock);
 326        dummy_systimer_update(dpcm);
 327        pos = dpcm->frac_pos / HZ;
 328        spin_unlock(&dpcm->lock);
 329        return pos;
 330}
 331
 332static int dummy_systimer_create(struct snd_pcm_substream *substream)
 333{
 334        struct dummy_systimer_pcm *dpcm;
 335
 336        dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 337        if (!dpcm)
 338                return -ENOMEM;
 339        substream->runtime->private_data = dpcm;
 340        init_timer(&dpcm->timer);
 341        dpcm->timer.data = (unsigned long) dpcm;
 342        dpcm->timer.function = dummy_systimer_callback;
 343        spin_lock_init(&dpcm->lock);
 344        dpcm->substream = substream;
 345        return 0;
 346}
 347
 348static void dummy_systimer_free(struct snd_pcm_substream *substream)
 349{
 350        kfree(substream->runtime->private_data);
 351}
 352
 353static struct dummy_timer_ops dummy_systimer_ops = {
 354        .create =       dummy_systimer_create,
 355        .free =         dummy_systimer_free,
 356        .prepare =      dummy_systimer_prepare,
 357        .start =        dummy_systimer_start,
 358        .stop =         dummy_systimer_stop,
 359        .pointer =      dummy_systimer_pointer,
 360};
 361
 362#ifdef CONFIG_HIGH_RES_TIMERS
 363/*
 364 * hrtimer interface
 365 */
 366
 367struct dummy_hrtimer_pcm {
 368        ktime_t base_time;
 369        ktime_t period_time;
 370        atomic_t running;
 371        struct hrtimer timer;
 372        struct tasklet_struct tasklet;
 373        struct snd_pcm_substream *substream;
 374};
 375
 376static void dummy_hrtimer_pcm_elapsed(unsigned long priv)
 377{
 378        struct dummy_hrtimer_pcm *dpcm = (struct dummy_hrtimer_pcm *)priv;
 379        if (atomic_read(&dpcm->running))
 380                snd_pcm_period_elapsed(dpcm->substream);
 381}
 382
 383static enum hrtimer_restart dummy_hrtimer_callback(struct hrtimer *timer)
 384{
 385        struct dummy_hrtimer_pcm *dpcm;
 386
 387        dpcm = container_of(timer, struct dummy_hrtimer_pcm, timer);
 388        if (!atomic_read(&dpcm->running))
 389                return HRTIMER_NORESTART;
 390        tasklet_schedule(&dpcm->tasklet);
 391        hrtimer_forward_now(timer, dpcm->period_time);
 392        return HRTIMER_RESTART;
 393}
 394
 395static int dummy_hrtimer_start(struct snd_pcm_substream *substream)
 396{
 397        struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 398
 399        dpcm->base_time = hrtimer_cb_get_time(&dpcm->timer);
 400        hrtimer_start(&dpcm->timer, dpcm->period_time, HRTIMER_MODE_REL);
 401        atomic_set(&dpcm->running, 1);
 402        return 0;
 403}
 404
 405static int dummy_hrtimer_stop(struct snd_pcm_substream *substream)
 406{
 407        struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 408
 409        atomic_set(&dpcm->running, 0);
 410        hrtimer_cancel(&dpcm->timer);
 411        return 0;
 412}
 413
 414static inline void dummy_hrtimer_sync(struct dummy_hrtimer_pcm *dpcm)
 415{
 416        tasklet_kill(&dpcm->tasklet);
 417}
 418
 419static snd_pcm_uframes_t
 420dummy_hrtimer_pointer(struct snd_pcm_substream *substream)
 421{
 422        struct snd_pcm_runtime *runtime = substream->runtime;
 423        struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 424        u64 delta;
 425        u32 pos;
 426
 427        delta = ktime_us_delta(hrtimer_cb_get_time(&dpcm->timer),
 428                               dpcm->base_time);
 429        delta = div_u64(delta * runtime->rate + 999999, 1000000);
 430        div_u64_rem(delta, runtime->buffer_size, &pos);
 431        return pos;
 432}
 433
 434static int dummy_hrtimer_prepare(struct snd_pcm_substream *substream)
 435{
 436        struct snd_pcm_runtime *runtime = substream->runtime;
 437        struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 438        unsigned int period, rate;
 439        long sec;
 440        unsigned long nsecs;
 441
 442        dummy_hrtimer_sync(dpcm);
 443        period = runtime->period_size;
 444        rate = runtime->rate;
 445        sec = period / rate;
 446        period %= rate;
 447        nsecs = div_u64((u64)period * 1000000000UL + rate - 1, rate);
 448        dpcm->period_time = ktime_set(sec, nsecs);
 449
 450        return 0;
 451}
 452
 453static int dummy_hrtimer_create(struct snd_pcm_substream *substream)
 454{
 455        struct dummy_hrtimer_pcm *dpcm;
 456
 457        dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 458        if (!dpcm)
 459                return -ENOMEM;
 460        substream->runtime->private_data = dpcm;
 461        hrtimer_init(&dpcm->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 462        dpcm->timer.function = dummy_hrtimer_callback;
 463        dpcm->substream = substream;
 464        atomic_set(&dpcm->running, 0);
 465        tasklet_init(&dpcm->tasklet, dummy_hrtimer_pcm_elapsed,
 466                     (unsigned long)dpcm);
 467        return 0;
 468}
 469
 470static void dummy_hrtimer_free(struct snd_pcm_substream *substream)
 471{
 472        struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 473        dummy_hrtimer_sync(dpcm);
 474        kfree(dpcm);
 475}
 476
 477static struct dummy_timer_ops dummy_hrtimer_ops = {
 478        .create =       dummy_hrtimer_create,
 479        .free =         dummy_hrtimer_free,
 480        .prepare =      dummy_hrtimer_prepare,
 481        .start =        dummy_hrtimer_start,
 482        .stop =         dummy_hrtimer_stop,
 483        .pointer =      dummy_hrtimer_pointer,
 484};
 485
 486#endif /* CONFIG_HIGH_RES_TIMERS */
 487
 488/*
 489 * PCM interface
 490 */
 491
 492static int dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 493{
 494        struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 495
 496        switch (cmd) {
 497        case SNDRV_PCM_TRIGGER_START:
 498        case SNDRV_PCM_TRIGGER_RESUME:
 499                return dummy->timer_ops->start(substream);
 500        case SNDRV_PCM_TRIGGER_STOP:
 501        case SNDRV_PCM_TRIGGER_SUSPEND:
 502                return dummy->timer_ops->stop(substream);
 503        }
 504        return -EINVAL;
 505}
 506
 507static int dummy_pcm_prepare(struct snd_pcm_substream *substream)
 508{
 509        struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 510
 511        return dummy->timer_ops->prepare(substream);
 512}
 513
 514static snd_pcm_uframes_t dummy_pcm_pointer(struct snd_pcm_substream *substream)
 515{
 516        struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 517
 518        return dummy->timer_ops->pointer(substream);
 519}
 520
 521static struct snd_pcm_hardware dummy_pcm_hardware = {
 522        .info =                 (SNDRV_PCM_INFO_MMAP |
 523                                 SNDRV_PCM_INFO_INTERLEAVED |
 524                                 SNDRV_PCM_INFO_RESUME |
 525                                 SNDRV_PCM_INFO_MMAP_VALID),
 526        .formats =              USE_FORMATS,
 527        .rates =                USE_RATE,
 528        .rate_min =             USE_RATE_MIN,
 529        .rate_max =             USE_RATE_MAX,
 530        .channels_min =         USE_CHANNELS_MIN,
 531        .channels_max =         USE_CHANNELS_MAX,
 532        .buffer_bytes_max =     MAX_BUFFER_SIZE,
 533        .period_bytes_min =     MIN_PERIOD_SIZE,
 534        .period_bytes_max =     MAX_PERIOD_SIZE,
 535        .periods_min =          USE_PERIODS_MIN,
 536        .periods_max =          USE_PERIODS_MAX,
 537        .fifo_size =            0,
 538};
 539
 540static int dummy_pcm_hw_params(struct snd_pcm_substream *substream,
 541                               struct snd_pcm_hw_params *hw_params)
 542{
 543        if (fake_buffer) {
 544                /* runtime->dma_bytes has to be set manually to allow mmap */
 545                substream->runtime->dma_bytes = params_buffer_bytes(hw_params);
 546                return 0;
 547        }
 548        return snd_pcm_lib_malloc_pages(substream,
 549                                        params_buffer_bytes(hw_params));
 550}
 551
 552static int dummy_pcm_hw_free(struct snd_pcm_substream *substream)
 553{
 554        if (fake_buffer)
 555                return 0;
 556        return snd_pcm_lib_free_pages(substream);
 557}
 558
 559static int dummy_pcm_open(struct snd_pcm_substream *substream)
 560{
 561        struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 562        struct dummy_model *model = dummy->model;
 563        struct snd_pcm_runtime *runtime = substream->runtime;
 564        int err;
 565
 566        dummy->timer_ops = &dummy_systimer_ops;
 567#ifdef CONFIG_HIGH_RES_TIMERS
 568        if (hrtimer)
 569                dummy->timer_ops = &dummy_hrtimer_ops;
 570#endif
 571
 572        err = dummy->timer_ops->create(substream);
 573        if (err < 0)
 574                return err;
 575
 576        runtime->hw = dummy->pcm_hw;
 577        if (substream->pcm->device & 1) {
 578                runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
 579                runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
 580        }
 581        if (substream->pcm->device & 2)
 582                runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
 583                                      SNDRV_PCM_INFO_MMAP_VALID);
 584
 585        if (model == NULL)
 586                return 0;
 587
 588        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 589                if (model->playback_constraints)
 590                        err = model->playback_constraints(substream->runtime);
 591        } else {
 592                if (model->capture_constraints)
 593                        err = model->capture_constraints(substream->runtime);
 594        }
 595        if (err < 0) {
 596                dummy->timer_ops->free(substream);
 597                return err;
 598        }
 599        return 0;
 600}
 601
 602static int dummy_pcm_close(struct snd_pcm_substream *substream)
 603{
 604        struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 605        dummy->timer_ops->free(substream);
 606        return 0;
 607}
 608
 609/*
 610 * dummy buffer handling
 611 */
 612
 613static void *dummy_page[2];
 614
 615static void free_fake_buffer(void)
 616{
 617        if (fake_buffer) {
 618                int i;
 619                for (i = 0; i < 2; i++)
 620                        if (dummy_page[i]) {
 621                                free_page((unsigned long)dummy_page[i]);
 622                                dummy_page[i] = NULL;
 623                        }
 624        }
 625}
 626
 627static int alloc_fake_buffer(void)
 628{
 629        int i;
 630
 631        if (!fake_buffer)
 632                return 0;
 633        for (i = 0; i < 2; i++) {
 634                dummy_page[i] = (void *)get_zeroed_page(GFP_KERNEL);
 635                if (!dummy_page[i]) {
 636                        free_fake_buffer();
 637                        return -ENOMEM;
 638                }
 639        }
 640        return 0;
 641}
 642
 643static int dummy_pcm_copy(struct snd_pcm_substream *substream,
 644                          int channel, snd_pcm_uframes_t pos,
 645                          void __user *dst, snd_pcm_uframes_t count)
 646{
 647        return 0; /* do nothing */
 648}
 649
 650static int dummy_pcm_silence(struct snd_pcm_substream *substream,
 651                             int channel, snd_pcm_uframes_t pos,
 652                             snd_pcm_uframes_t count)
 653{
 654        return 0; /* do nothing */
 655}
 656
 657static struct page *dummy_pcm_page(struct snd_pcm_substream *substream,
 658                                   unsigned long offset)
 659{
 660        return virt_to_page(dummy_page[substream->stream]); /* the same page */
 661}
 662
 663static struct snd_pcm_ops dummy_pcm_ops = {
 664        .open =         dummy_pcm_open,
 665        .close =        dummy_pcm_close,
 666        .ioctl =        snd_pcm_lib_ioctl,
 667        .hw_params =    dummy_pcm_hw_params,
 668        .hw_free =      dummy_pcm_hw_free,
 669        .prepare =      dummy_pcm_prepare,
 670        .trigger =      dummy_pcm_trigger,
 671        .pointer =      dummy_pcm_pointer,
 672};
 673
 674static struct snd_pcm_ops dummy_pcm_ops_no_buf = {
 675        .open =         dummy_pcm_open,
 676        .close =        dummy_pcm_close,
 677        .ioctl =        snd_pcm_lib_ioctl,
 678        .hw_params =    dummy_pcm_hw_params,
 679        .hw_free =      dummy_pcm_hw_free,
 680        .prepare =      dummy_pcm_prepare,
 681        .trigger =      dummy_pcm_trigger,
 682        .pointer =      dummy_pcm_pointer,
 683        .copy =         dummy_pcm_copy,
 684        .silence =      dummy_pcm_silence,
 685        .page =         dummy_pcm_page,
 686};
 687
 688static int __devinit snd_card_dummy_pcm(struct snd_dummy *dummy, int device,
 689                                        int substreams)
 690{
 691        struct snd_pcm *pcm;
 692        struct snd_pcm_ops *ops;
 693        int err;
 694
 695        err = snd_pcm_new(dummy->card, "Dummy PCM", device,
 696                               substreams, substreams, &pcm);
 697        if (err < 0)
 698                return err;
 699        dummy->pcm = pcm;
 700        if (fake_buffer)
 701                ops = &dummy_pcm_ops_no_buf;
 702        else
 703                ops = &dummy_pcm_ops;
 704        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, ops);
 705        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, ops);
 706        pcm->private_data = dummy;
 707        pcm->info_flags = 0;
 708        strcpy(pcm->name, "Dummy PCM");
 709        if (!fake_buffer) {
 710                snd_pcm_lib_preallocate_pages_for_all(pcm,
 711                        SNDRV_DMA_TYPE_CONTINUOUS,
 712                        snd_dma_continuous_data(GFP_KERNEL),
 713                        0, 64*1024);
 714        }
 715        return 0;
 716}
 717
 718/*
 719 * mixer interface
 720 */
 721
 722#define DUMMY_VOLUME(xname, xindex, addr) \
 723{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
 724  .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ, \
 725  .name = xname, .index = xindex, \
 726  .info = snd_dummy_volume_info, \
 727  .get = snd_dummy_volume_get, .put = snd_dummy_volume_put, \
 728  .private_value = addr, \
 729  .tlv = { .p = db_scale_dummy } }
 730
 731static int snd_dummy_volume_info(struct snd_kcontrol *kcontrol,
 732                                 struct snd_ctl_elem_info *uinfo)
 733{
 734        uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 735        uinfo->count = 2;
 736        uinfo->value.integer.min = -50;
 737        uinfo->value.integer.max = 100;
 738        return 0;
 739}
 740 
 741static int snd_dummy_volume_get(struct snd_kcontrol *kcontrol,
 742                                struct snd_ctl_elem_value *ucontrol)
 743{
 744        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 745        int addr = kcontrol->private_value;
 746
 747        spin_lock_irq(&dummy->mixer_lock);
 748        ucontrol->value.integer.value[0] = dummy->mixer_volume[addr][0];
 749        ucontrol->value.integer.value[1] = dummy->mixer_volume[addr][1];
 750        spin_unlock_irq(&dummy->mixer_lock);
 751        return 0;
 752}
 753
 754static int snd_dummy_volume_put(struct snd_kcontrol *kcontrol,
 755                                struct snd_ctl_elem_value *ucontrol)
 756{
 757        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 758        int change, addr = kcontrol->private_value;
 759        int left, right;
 760
 761        left = ucontrol->value.integer.value[0];
 762        if (left < -50)
 763                left = -50;
 764        if (left > 100)
 765                left = 100;
 766        right = ucontrol->value.integer.value[1];
 767        if (right < -50)
 768                right = -50;
 769        if (right > 100)
 770                right = 100;
 771        spin_lock_irq(&dummy->mixer_lock);
 772        change = dummy->mixer_volume[addr][0] != left ||
 773                 dummy->mixer_volume[addr][1] != right;
 774        dummy->mixer_volume[addr][0] = left;
 775        dummy->mixer_volume[addr][1] = right;
 776        spin_unlock_irq(&dummy->mixer_lock);
 777        return change;
 778}
 779
 780static const DECLARE_TLV_DB_SCALE(db_scale_dummy, -4500, 30, 0);
 781
 782#define DUMMY_CAPSRC(xname, xindex, addr) \
 783{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
 784  .info = snd_dummy_capsrc_info, \
 785  .get = snd_dummy_capsrc_get, .put = snd_dummy_capsrc_put, \
 786  .private_value = addr }
 787
 788#define snd_dummy_capsrc_info   snd_ctl_boolean_stereo_info
 789 
 790static int snd_dummy_capsrc_get(struct snd_kcontrol *kcontrol,
 791                                struct snd_ctl_elem_value *ucontrol)
 792{
 793        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 794        int addr = kcontrol->private_value;
 795
 796        spin_lock_irq(&dummy->mixer_lock);
 797        ucontrol->value.integer.value[0] = dummy->capture_source[addr][0];
 798        ucontrol->value.integer.value[1] = dummy->capture_source[addr][1];
 799        spin_unlock_irq(&dummy->mixer_lock);
 800        return 0;
 801}
 802
 803static int snd_dummy_capsrc_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
 804{
 805        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 806        int change, addr = kcontrol->private_value;
 807        int left, right;
 808
 809        left = ucontrol->value.integer.value[0] & 1;
 810        right = ucontrol->value.integer.value[1] & 1;
 811        spin_lock_irq(&dummy->mixer_lock);
 812        change = dummy->capture_source[addr][0] != left &&
 813                 dummy->capture_source[addr][1] != right;
 814        dummy->capture_source[addr][0] = left;
 815        dummy->capture_source[addr][1] = right;
 816        spin_unlock_irq(&dummy->mixer_lock);
 817        return change;
 818}
 819
 820static struct snd_kcontrol_new snd_dummy_controls[] = {
 821DUMMY_VOLUME("Master Volume", 0, MIXER_ADDR_MASTER),
 822DUMMY_CAPSRC("Master Capture Switch", 0, MIXER_ADDR_MASTER),
 823DUMMY_VOLUME("Synth Volume", 0, MIXER_ADDR_SYNTH),
 824DUMMY_CAPSRC("Synth Capture Switch", 0, MIXER_ADDR_SYNTH),
 825DUMMY_VOLUME("Line Volume", 0, MIXER_ADDR_LINE),
 826DUMMY_CAPSRC("Line Capture Switch", 0, MIXER_ADDR_LINE),
 827DUMMY_VOLUME("Mic Volume", 0, MIXER_ADDR_MIC),
 828DUMMY_CAPSRC("Mic Capture Switch", 0, MIXER_ADDR_MIC),
 829DUMMY_VOLUME("CD Volume", 0, MIXER_ADDR_CD),
 830DUMMY_CAPSRC("CD Capture Switch", 0, MIXER_ADDR_CD)
 831};
 832
 833static int __devinit snd_card_dummy_new_mixer(struct snd_dummy *dummy)
 834{
 835        struct snd_card *card = dummy->card;
 836        unsigned int idx;
 837        int err;
 838
 839        spin_lock_init(&dummy->mixer_lock);
 840        strcpy(card->mixername, "Dummy Mixer");
 841
 842        for (idx = 0; idx < ARRAY_SIZE(snd_dummy_controls); idx++) {
 843                err = snd_ctl_add(card, snd_ctl_new1(&snd_dummy_controls[idx], dummy));
 844                if (err < 0)
 845                        return err;
 846        }
 847        return 0;
 848}
 849
 850#if defined(CONFIG_SND_DEBUG) && defined(CONFIG_PROC_FS)
 851/*
 852 * proc interface
 853 */
 854static void print_formats(struct snd_dummy *dummy,
 855                          struct snd_info_buffer *buffer)
 856{
 857        int i;
 858
 859        for (i = 0; i < SNDRV_PCM_FORMAT_LAST; i++) {
 860                if (dummy->pcm_hw.formats & (1ULL << i))
 861                        snd_iprintf(buffer, " %s", snd_pcm_format_name(i));
 862        }
 863}
 864
 865static void print_rates(struct snd_dummy *dummy,
 866                        struct snd_info_buffer *buffer)
 867{
 868        static int rates[] = {
 869                5512, 8000, 11025, 16000, 22050, 32000, 44100, 48000,
 870                64000, 88200, 96000, 176400, 192000,
 871        };
 872        int i;
 873
 874        if (dummy->pcm_hw.rates & SNDRV_PCM_RATE_CONTINUOUS)
 875                snd_iprintf(buffer, " continuous");
 876        if (dummy->pcm_hw.rates & SNDRV_PCM_RATE_KNOT)
 877                snd_iprintf(buffer, " knot");
 878        for (i = 0; i < ARRAY_SIZE(rates); i++)
 879                if (dummy->pcm_hw.rates & (1 << i))
 880                        snd_iprintf(buffer, " %d", rates[i]);
 881}
 882
 883#define get_dummy_int_ptr(dummy, ofs) \
 884        (unsigned int *)((char *)&((dummy)->pcm_hw) + (ofs))
 885#define get_dummy_ll_ptr(dummy, ofs) \
 886        (unsigned long long *)((char *)&((dummy)->pcm_hw) + (ofs))
 887
 888struct dummy_hw_field {
 889        const char *name;
 890        const char *format;
 891        unsigned int offset;
 892        unsigned int size;
 893};
 894#define FIELD_ENTRY(item, fmt) {                   \
 895        .name = #item,                             \
 896        .format = fmt,                             \
 897        .offset = offsetof(struct snd_pcm_hardware, item), \
 898        .size = sizeof(dummy_pcm_hardware.item) }
 899
 900static struct dummy_hw_field fields[] = {
 901        FIELD_ENTRY(formats, "%#llx"),
 902        FIELD_ENTRY(rates, "%#x"),
 903        FIELD_ENTRY(rate_min, "%d"),
 904        FIELD_ENTRY(rate_max, "%d"),
 905        FIELD_ENTRY(channels_min, "%d"),
 906        FIELD_ENTRY(channels_max, "%d"),
 907        FIELD_ENTRY(buffer_bytes_max, "%ld"),
 908        FIELD_ENTRY(period_bytes_min, "%ld"),
 909        FIELD_ENTRY(period_bytes_max, "%ld"),
 910        FIELD_ENTRY(periods_min, "%d"),
 911        FIELD_ENTRY(periods_max, "%d"),
 912};
 913
 914static void dummy_proc_read(struct snd_info_entry *entry,
 915                            struct snd_info_buffer *buffer)
 916{
 917        struct snd_dummy *dummy = entry->private_data;
 918        int i;
 919
 920        for (i = 0; i < ARRAY_SIZE(fields); i++) {
 921                snd_iprintf(buffer, "%s ", fields[i].name);
 922                if (fields[i].size == sizeof(int))
 923                        snd_iprintf(buffer, fields[i].format,
 924                                *get_dummy_int_ptr(dummy, fields[i].offset));
 925                else
 926                        snd_iprintf(buffer, fields[i].format,
 927                                *get_dummy_ll_ptr(dummy, fields[i].offset));
 928                if (!strcmp(fields[i].name, "formats"))
 929                        print_formats(dummy, buffer);
 930                else if (!strcmp(fields[i].name, "rates"))
 931                        print_rates(dummy, buffer);
 932                snd_iprintf(buffer, "\n");
 933        }
 934}
 935
 936static void dummy_proc_write(struct snd_info_entry *entry,
 937                             struct snd_info_buffer *buffer)
 938{
 939        struct snd_dummy *dummy = entry->private_data;
 940        char line[64];
 941
 942        while (!snd_info_get_line(buffer, line, sizeof(line))) {
 943                char item[20];
 944                const char *ptr;
 945                unsigned long long val;
 946                int i;
 947
 948                ptr = snd_info_get_str(item, line, sizeof(item));
 949                for (i = 0; i < ARRAY_SIZE(fields); i++) {
 950                        if (!strcmp(item, fields[i].name))
 951                                break;
 952                }
 953                if (i >= ARRAY_SIZE(fields))
 954                        continue;
 955                snd_info_get_str(item, ptr, sizeof(item));
 956                if (strict_strtoull(item, 0, &val))
 957                        continue;
 958                if (fields[i].size == sizeof(int))
 959                        *get_dummy_int_ptr(dummy, fields[i].offset) = val;
 960                else
 961                        *get_dummy_ll_ptr(dummy, fields[i].offset) = val;
 962        }
 963}
 964
 965static void __devinit dummy_proc_init(struct snd_dummy *chip)
 966{
 967        struct snd_info_entry *entry;
 968
 969        if (!snd_card_proc_new(chip->card, "dummy_pcm", &entry)) {
 970                snd_info_set_text_ops(entry, chip, dummy_proc_read);
 971                entry->c.text.write = dummy_proc_write;
 972                entry->mode |= S_IWUSR;
 973                entry->private_data = chip;
 974        }
 975}
 976#else
 977#define dummy_proc_init(x)
 978#endif /* CONFIG_SND_DEBUG && CONFIG_PROC_FS */
 979
 980static int __devinit snd_dummy_probe(struct platform_device *devptr)
 981{
 982        struct snd_card *card;
 983        struct snd_dummy *dummy;
 984        struct dummy_model *m = NULL, **mdl;
 985        int idx, err;
 986        int dev = devptr->id;
 987
 988        err = snd_card_create(index[dev], id[dev], THIS_MODULE,
 989                              sizeof(struct snd_dummy), &card);
 990        if (err < 0)
 991                return err;
 992        dummy = card->private_data;
 993        dummy->card = card;
 994        for (mdl = dummy_models; *mdl && model[dev]; mdl++) {
 995                if (strcmp(model[dev], (*mdl)->name) == 0) {
 996                        printk(KERN_INFO
 997                                "snd-dummy: Using model '%s' for card %i\n",
 998                                (*mdl)->name, card->number);
 999                        m = dummy->model = *mdl;
1000                        break;
1001                }
1002        }
1003        for (idx = 0; idx < MAX_PCM_DEVICES && idx < pcm_devs[dev]; idx++) {
1004                if (pcm_substreams[dev] < 1)
1005                        pcm_substreams[dev] = 1;
1006                if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
1007                        pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
1008                err = snd_card_dummy_pcm(dummy, idx, pcm_substreams[dev]);
1009                if (err < 0)
1010                        goto __nodev;
1011        }
1012
1013        dummy->pcm_hw = dummy_pcm_hardware;
1014        if (m) {
1015                if (m->formats)
1016                        dummy->pcm_hw.formats = m->formats;
1017                if (m->buffer_bytes_max)
1018                        dummy->pcm_hw.buffer_bytes_max = m->buffer_bytes_max;
1019                if (m->period_bytes_min)
1020                        dummy->pcm_hw.period_bytes_min = m->period_bytes_min;
1021                if (m->period_bytes_max)
1022                        dummy->pcm_hw.period_bytes_max = m->period_bytes_max;
1023                if (m->periods_min)
1024                        dummy->pcm_hw.periods_min = m->periods_min;
1025                if (m->periods_max)
1026                        dummy->pcm_hw.periods_max = m->periods_max;
1027                if (m->rates)
1028                        dummy->pcm_hw.rates = m->rates;
1029                if (m->rate_min)
1030                        dummy->pcm_hw.rate_min = m->rate_min;
1031                if (m->rate_max)
1032                        dummy->pcm_hw.rate_max = m->rate_max;
1033                if (m->channels_min)
1034                        dummy->pcm_hw.channels_min = m->channels_min;
1035                if (m->channels_max)
1036                        dummy->pcm_hw.channels_max = m->channels_max;
1037        }
1038
1039        err = snd_card_dummy_new_mixer(dummy);
1040        if (err < 0)
1041                goto __nodev;
1042        strcpy(card->driver, "Dummy");
1043        strcpy(card->shortname, "Dummy");
1044        sprintf(card->longname, "Dummy %i", dev + 1);
1045
1046        dummy_proc_init(dummy);
1047
1048        snd_card_set_dev(card, &devptr->dev);
1049
1050        err = snd_card_register(card);
1051        if (err == 0) {
1052                platform_set_drvdata(devptr, card);
1053                return 0;
1054        }
1055      __nodev:
1056        snd_card_free(card);
1057        return err;
1058}
1059
1060static int __devexit snd_dummy_remove(struct platform_device *devptr)
1061{
1062        snd_card_free(platform_get_drvdata(devptr));
1063        platform_set_drvdata(devptr, NULL);
1064        return 0;
1065}
1066
1067#ifdef CONFIG_PM_SLEEP
1068static int snd_dummy_suspend(struct device *pdev)
1069{
1070        struct snd_card *card = dev_get_drvdata(pdev);
1071        struct snd_dummy *dummy = card->private_data;
1072
1073        snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
1074        snd_pcm_suspend_all(dummy->pcm);
1075        return 0;
1076}
1077        
1078static int snd_dummy_resume(struct device *pdev)
1079{
1080        struct snd_card *card = dev_get_drvdata(pdev);
1081
1082        snd_power_change_state(card, SNDRV_CTL_POWER_D0);
1083        return 0;
1084}
1085
1086static SIMPLE_DEV_PM_OPS(snd_dummy_pm, snd_dummy_suspend, snd_dummy_resume);
1087#define SND_DUMMY_PM_OPS        &snd_dummy_pm
1088#else
1089#define SND_DUMMY_PM_OPS        NULL
1090#endif
1091
1092#define SND_DUMMY_DRIVER        "snd_dummy"
1093
1094static struct platform_driver snd_dummy_driver = {
1095        .probe          = snd_dummy_probe,
1096        .remove         = __devexit_p(snd_dummy_remove),
1097        .driver         = {
1098                .name   = SND_DUMMY_DRIVER,
1099                .owner  = THIS_MODULE,
1100                .pm     = SND_DUMMY_PM_OPS,
1101        },
1102};
1103
1104static void snd_dummy_unregister_all(void)
1105{
1106        int i;
1107
1108        for (i = 0; i < ARRAY_SIZE(devices); ++i)
1109                platform_device_unregister(devices[i]);
1110        platform_driver_unregister(&snd_dummy_driver);
1111        free_fake_buffer();
1112}
1113
1114static int __init alsa_card_dummy_init(void)
1115{
1116        int i, cards, err;
1117
1118        err = platform_driver_register(&snd_dummy_driver);
1119        if (err < 0)
1120                return err;
1121
1122        err = alloc_fake_buffer();
1123        if (err < 0) {
1124                platform_driver_unregister(&snd_dummy_driver);
1125                return err;
1126        }
1127
1128        cards = 0;
1129        for (i = 0; i < SNDRV_CARDS; i++) {
1130                struct platform_device *device;
1131                if (! enable[i])
1132                        continue;
1133                device = platform_device_register_simple(SND_DUMMY_DRIVER,
1134                                                         i, NULL, 0);
1135                if (IS_ERR(device))
1136                        continue;
1137                if (!platform_get_drvdata(device)) {
1138                        platform_device_unregister(device);
1139                        continue;
1140                }
1141                devices[i] = device;
1142                cards++;
1143        }
1144        if (!cards) {
1145#ifdef MODULE
1146                printk(KERN_ERR "Dummy soundcard not found or device busy\n");
1147#endif
1148                snd_dummy_unregister_all();
1149                return -ENODEV;
1150        }
1151        return 0;
1152}
1153
1154static void __exit alsa_card_dummy_exit(void)
1155{
1156        snd_dummy_unregister_all();
1157}
1158
1159module_init(alsa_card_dummy_init)
1160module_exit(alsa_card_dummy_exit)
1161
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