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        int iobox;
 138        struct snd_kcontrol *cd_volume_ctl;
 139        struct snd_kcontrol *cd_switch_ctl;
 140        const struct dummy_timer_ops *timer_ops;
 141};
 142
 143/*
 144 * card models
 145 */
 146
 147static int emu10k1_playback_constraints(struct snd_pcm_runtime *runtime)
 148{
 149        int err;
 150        err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 151        if (err < 0)
 152                return err;
 153        err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX);
 154        if (err < 0)
 155                return err;
 156        return 0;
 157}
 158
 159struct dummy_model model_emu10k1 = {
 160        .name = "emu10k1",
 161        .playback_constraints = emu10k1_playback_constraints,
 162        .buffer_bytes_max = 128 * 1024,
 163};
 164
 165struct dummy_model model_rme9652 = {
 166        .name = "rme9652",
 167        .buffer_bytes_max = 26 * 64 * 1024,
 168        .formats = SNDRV_PCM_FMTBIT_S32_LE,
 169        .channels_min = 26,
 170        .channels_max = 26,
 171        .periods_min = 2,
 172        .periods_max = 2,
 173};
 174
 175struct dummy_model model_ice1712 = {
 176        .name = "ice1712",
 177        .buffer_bytes_max = 256 * 1024,
 178        .formats = SNDRV_PCM_FMTBIT_S32_LE,
 179        .channels_min = 10,
 180        .channels_max = 10,
 181        .periods_min = 1,
 182        .periods_max = 1024,
 183};
 184
 185struct dummy_model model_uda1341 = {
 186        .name = "uda1341",
 187        .buffer_bytes_max = 16380,
 188        .formats = SNDRV_PCM_FMTBIT_S16_LE,
 189        .channels_min = 2,
 190        .channels_max = 2,
 191        .periods_min = 2,
 192        .periods_max = 255,
 193};
 194
 195struct dummy_model model_ac97 = {
 196        .name = "ac97",
 197        .formats = SNDRV_PCM_FMTBIT_S16_LE,
 198        .channels_min = 2,
 199        .channels_max = 2,
 200        .rates = SNDRV_PCM_RATE_48000,
 201        .rate_min = 48000,
 202        .rate_max = 48000,
 203};
 204
 205struct dummy_model model_ca0106 = {
 206        .name = "ca0106",
 207        .formats = SNDRV_PCM_FMTBIT_S16_LE,
 208        .buffer_bytes_max = ((65536-64)*8),
 209        .period_bytes_max = (65536-64),
 210        .periods_min = 2,
 211        .periods_max = 8,
 212        .channels_min = 2,
 213        .channels_max = 2,
 214        .rates = SNDRV_PCM_RATE_48000|SNDRV_PCM_RATE_96000|SNDRV_PCM_RATE_192000,
 215        .rate_min = 48000,
 216        .rate_max = 192000,
 217};
 218
 219struct dummy_model *dummy_models[] = {
 220        &model_emu10k1,
 221        &model_rme9652,
 222        &model_ice1712,
 223        &model_uda1341,
 224        &model_ac97,
 225        &model_ca0106,
 226        NULL
 227};
 228
 229/*
 230 * system timer interface
 231 */
 232
 233struct dummy_systimer_pcm {
 234        spinlock_t lock;
 235        struct timer_list timer;
 236        unsigned long base_time;
 237        unsigned int frac_pos;  /* fractional sample position (based HZ) */
 238        unsigned int frac_period_rest;
 239        unsigned int frac_buffer_size;  /* buffer_size * HZ */
 240        unsigned int frac_period_size;  /* period_size * HZ */
 241        unsigned int rate;
 242        int elapsed;
 243        struct snd_pcm_substream *substream;
 244};
 245
 246static void dummy_systimer_rearm(struct dummy_systimer_pcm *dpcm)
 247{
 248        dpcm->timer.expires = jiffies +
 249                (dpcm->frac_period_rest + dpcm->rate - 1) / dpcm->rate;
 250        add_timer(&dpcm->timer);
 251}
 252
 253static void dummy_systimer_update(struct dummy_systimer_pcm *dpcm)
 254{
 255        unsigned long delta;
 256
 257        delta = jiffies - dpcm->base_time;
 258        if (!delta)
 259                return;
 260        dpcm->base_time += delta;
 261        delta *= dpcm->rate;
 262        dpcm->frac_pos += delta;
 263        while (dpcm->frac_pos >= dpcm->frac_buffer_size)
 264                dpcm->frac_pos -= dpcm->frac_buffer_size;
 265        while (dpcm->frac_period_rest <= delta) {
 266                dpcm->elapsed++;
 267                dpcm->frac_period_rest += dpcm->frac_period_size;
 268        }
 269        dpcm->frac_period_rest -= delta;
 270}
 271
 272static int dummy_systimer_start(struct snd_pcm_substream *substream)
 273{
 274        struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 275        spin_lock(&dpcm->lock);
 276        dpcm->base_time = jiffies;
 277        dummy_systimer_rearm(dpcm);
 278        spin_unlock(&dpcm->lock);
 279        return 0;
 280}
 281
 282static int dummy_systimer_stop(struct snd_pcm_substream *substream)
 283{
 284        struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 285        spin_lock(&dpcm->lock);
 286        del_timer(&dpcm->timer);
 287        spin_unlock(&dpcm->lock);
 288        return 0;
 289}
 290
 291static int dummy_systimer_prepare(struct snd_pcm_substream *substream)
 292{
 293        struct snd_pcm_runtime *runtime = substream->runtime;
 294        struct dummy_systimer_pcm *dpcm = runtime->private_data;
 295
 296        dpcm->frac_pos = 0;
 297        dpcm->rate = runtime->rate;
 298        dpcm->frac_buffer_size = runtime->buffer_size * HZ;
 299        dpcm->frac_period_size = runtime->period_size * HZ;
 300        dpcm->frac_period_rest = dpcm->frac_period_size;
 301        dpcm->elapsed = 0;
 302
 303        return 0;
 304}
 305
 306static void dummy_systimer_callback(unsigned long data)
 307{
 308        struct dummy_systimer_pcm *dpcm = (struct dummy_systimer_pcm *)data;
 309        unsigned long flags;
 310        int elapsed = 0;
 311        
 312        spin_lock_irqsave(&dpcm->lock, flags);
 313        dummy_systimer_update(dpcm);
 314        dummy_systimer_rearm(dpcm);
 315        elapsed = dpcm->elapsed;
 316        dpcm->elapsed = 0;
 317        spin_unlock_irqrestore(&dpcm->lock, flags);
 318        if (elapsed)
 319                snd_pcm_period_elapsed(dpcm->substream);
 320}
 321
 322static snd_pcm_uframes_t
 323dummy_systimer_pointer(struct snd_pcm_substream *substream)
 324{
 325        struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 326        snd_pcm_uframes_t pos;
 327
 328        spin_lock(&dpcm->lock);
 329        dummy_systimer_update(dpcm);
 330        pos = dpcm->frac_pos / HZ;
 331        spin_unlock(&dpcm->lock);
 332        return pos;
 333}
 334
 335static int dummy_systimer_create(struct snd_pcm_substream *substream)
 336{
 337        struct dummy_systimer_pcm *dpcm;
 338
 339        dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 340        if (!dpcm)
 341                return -ENOMEM;
 342        substream->runtime->private_data = dpcm;
 343        init_timer(&dpcm->timer);
 344        dpcm->timer.data = (unsigned long) dpcm;
 345        dpcm->timer.function = dummy_systimer_callback;
 346        spin_lock_init(&dpcm->lock);
 347        dpcm->substream = substream;
 348        return 0;
 349}
 350
 351static void dummy_systimer_free(struct snd_pcm_substream *substream)
 352{
 353        kfree(substream->runtime->private_data);
 354}
 355
 356static struct dummy_timer_ops dummy_systimer_ops = {
 357        .create =       dummy_systimer_create,
 358        .free =         dummy_systimer_free,
 359        .prepare =      dummy_systimer_prepare,
 360        .start =        dummy_systimer_start,
 361        .stop =         dummy_systimer_stop,
 362        .pointer =      dummy_systimer_pointer,
 363};
 364
 365#ifdef CONFIG_HIGH_RES_TIMERS
 366/*
 367 * hrtimer interface
 368 */
 369
 370struct dummy_hrtimer_pcm {
 371        ktime_t base_time;
 372        ktime_t period_time;
 373        atomic_t running;
 374        struct hrtimer timer;
 375        struct tasklet_struct tasklet;
 376        struct snd_pcm_substream *substream;
 377};
 378
 379static void dummy_hrtimer_pcm_elapsed(unsigned long priv)
 380{
 381        struct dummy_hrtimer_pcm *dpcm = (struct dummy_hrtimer_pcm *)priv;
 382        if (atomic_read(&dpcm->running))
 383                snd_pcm_period_elapsed(dpcm->substream);
 384}
 385
 386static enum hrtimer_restart dummy_hrtimer_callback(struct hrtimer *timer)
 387{
 388        struct dummy_hrtimer_pcm *dpcm;
 389
 390        dpcm = container_of(timer, struct dummy_hrtimer_pcm, timer);
 391        if (!atomic_read(&dpcm->running))
 392                return HRTIMER_NORESTART;
 393        tasklet_schedule(&dpcm->tasklet);
 394        hrtimer_forward_now(timer, dpcm->period_time);
 395        return HRTIMER_RESTART;
 396}
 397
 398static int dummy_hrtimer_start(struct snd_pcm_substream *substream)
 399{
 400        struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 401
 402        dpcm->base_time = hrtimer_cb_get_time(&dpcm->timer);
 403        hrtimer_start(&dpcm->timer, dpcm->period_time, HRTIMER_MODE_REL);
 404        atomic_set(&dpcm->running, 1);
 405        return 0;
 406}
 407
 408static int dummy_hrtimer_stop(struct snd_pcm_substream *substream)
 409{
 410        struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 411
 412        atomic_set(&dpcm->running, 0);
 413        hrtimer_cancel(&dpcm->timer);
 414        return 0;
 415}
 416
 417static inline void dummy_hrtimer_sync(struct dummy_hrtimer_pcm *dpcm)
 418{
 419        tasklet_kill(&dpcm->tasklet);
 420}
 421
 422static snd_pcm_uframes_t
 423dummy_hrtimer_pointer(struct snd_pcm_substream *substream)
 424{
 425        struct snd_pcm_runtime *runtime = substream->runtime;
 426        struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 427        u64 delta;
 428        u32 pos;
 429
 430        delta = ktime_us_delta(hrtimer_cb_get_time(&dpcm->timer),
 431                               dpcm->base_time);
 432        delta = div_u64(delta * runtime->rate + 999999, 1000000);
 433        div_u64_rem(delta, runtime->buffer_size, &pos);
 434        return pos;
 435}
 436
 437static int dummy_hrtimer_prepare(struct snd_pcm_substream *substream)
 438{
 439        struct snd_pcm_runtime *runtime = substream->runtime;
 440        struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 441        unsigned int period, rate;
 442        long sec;
 443        unsigned long nsecs;
 444
 445        dummy_hrtimer_sync(dpcm);
 446        period = runtime->period_size;
 447        rate = runtime->rate;
 448        sec = period / rate;
 449        period %= rate;
 450        nsecs = div_u64((u64)period * 1000000000UL + rate - 1, rate);
 451        dpcm->period_time = ktime_set(sec, nsecs);
 452
 453        return 0;
 454}
 455
 456static int dummy_hrtimer_create(struct snd_pcm_substream *substream)
 457{
 458        struct dummy_hrtimer_pcm *dpcm;
 459
 460        dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 461        if (!dpcm)
 462                return -ENOMEM;
 463        substream->runtime->private_data = dpcm;
 464        hrtimer_init(&dpcm->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 465        dpcm->timer.function = dummy_hrtimer_callback;
 466        dpcm->substream = substream;
 467        atomic_set(&dpcm->running, 0);
 468        tasklet_init(&dpcm->tasklet, dummy_hrtimer_pcm_elapsed,
 469                     (unsigned long)dpcm);
 470        return 0;
 471}
 472
 473static void dummy_hrtimer_free(struct snd_pcm_substream *substream)
 474{
 475        struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 476        dummy_hrtimer_sync(dpcm);
 477        kfree(dpcm);
 478}
 479
 480static struct dummy_timer_ops dummy_hrtimer_ops = {
 481        .create =       dummy_hrtimer_create,
 482        .free =         dummy_hrtimer_free,
 483        .prepare =      dummy_hrtimer_prepare,
 484        .start =        dummy_hrtimer_start,
 485        .stop =         dummy_hrtimer_stop,
 486        .pointer =      dummy_hrtimer_pointer,
 487};
 488
 489#endif /* CONFIG_HIGH_RES_TIMERS */
 490
 491/*
 492 * PCM interface
 493 */
 494
 495static int dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 496{
 497        struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 498
 499        switch (cmd) {
 500        case SNDRV_PCM_TRIGGER_START:
 501        case SNDRV_PCM_TRIGGER_RESUME:
 502                return dummy->timer_ops->start(substream);
 503        case SNDRV_PCM_TRIGGER_STOP:
 504        case SNDRV_PCM_TRIGGER_SUSPEND:
 505                return dummy->timer_ops->stop(substream);
 506        }
 507        return -EINVAL;
 508}
 509
 510static int dummy_pcm_prepare(struct snd_pcm_substream *substream)
 511{
 512        struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 513
 514        return dummy->timer_ops->prepare(substream);
 515}
 516
 517static snd_pcm_uframes_t dummy_pcm_pointer(struct snd_pcm_substream *substream)
 518{
 519        struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 520
 521        return dummy->timer_ops->pointer(substream);
 522}
 523
 524static struct snd_pcm_hardware dummy_pcm_hardware = {
 525        .info =                 (SNDRV_PCM_INFO_MMAP |
 526                                 SNDRV_PCM_INFO_INTERLEAVED |
 527                                 SNDRV_PCM_INFO_RESUME |
 528                                 SNDRV_PCM_INFO_MMAP_VALID),
 529        .formats =              USE_FORMATS,
 530        .rates =                USE_RATE,
 531        .rate_min =             USE_RATE_MIN,
 532        .rate_max =             USE_RATE_MAX,
 533        .channels_min =         USE_CHANNELS_MIN,
 534        .channels_max =         USE_CHANNELS_MAX,
 535        .buffer_bytes_max =     MAX_BUFFER_SIZE,
 536        .period_bytes_min =     MIN_PERIOD_SIZE,
 537        .period_bytes_max =     MAX_PERIOD_SIZE,
 538        .periods_min =          USE_PERIODS_MIN,
 539        .periods_max =          USE_PERIODS_MAX,
 540        .fifo_size =            0,
 541};
 542
 543static int dummy_pcm_hw_params(struct snd_pcm_substream *substream,
 544                               struct snd_pcm_hw_params *hw_params)
 545{
 546        if (fake_buffer) {
 547                /* runtime->dma_bytes has to be set manually to allow mmap */
 548                substream->runtime->dma_bytes = params_buffer_bytes(hw_params);
 549                return 0;
 550        }
 551        return snd_pcm_lib_malloc_pages(substream,
 552                                        params_buffer_bytes(hw_params));
 553}
 554
 555static int dummy_pcm_hw_free(struct snd_pcm_substream *substream)
 556{
 557        if (fake_buffer)
 558                return 0;
 559        return snd_pcm_lib_free_pages(substream);
 560}
 561
 562static int dummy_pcm_open(struct snd_pcm_substream *substream)
 563{
 564        struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 565        struct dummy_model *model = dummy->model;
 566        struct snd_pcm_runtime *runtime = substream->runtime;
 567        int err;
 568
 569        dummy->timer_ops = &dummy_systimer_ops;
 570#ifdef CONFIG_HIGH_RES_TIMERS
 571        if (hrtimer)
 572                dummy->timer_ops = &dummy_hrtimer_ops;
 573#endif
 574
 575        err = dummy->timer_ops->create(substream);
 576        if (err < 0)
 577                return err;
 578
 579        runtime->hw = dummy->pcm_hw;
 580        if (substream->pcm->device & 1) {
 581                runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
 582                runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
 583        }
 584        if (substream->pcm->device & 2)
 585                runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
 586                                      SNDRV_PCM_INFO_MMAP_VALID);
 587
 588        if (model == NULL)
 589                return 0;
 590
 591        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 592                if (model->playback_constraints)
 593                        err = model->playback_constraints(substream->runtime);
 594        } else {
 595                if (model->capture_constraints)
 596                        err = model->capture_constraints(substream->runtime);
 597        }
 598        if (err < 0) {
 599                dummy->timer_ops->free(substream);
 600                return err;
 601        }
 602        return 0;
 603}
 604
 605static int dummy_pcm_close(struct snd_pcm_substream *substream)
 606{
 607        struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 608        dummy->timer_ops->free(substream);
 609        return 0;
 610}
 611
 612/*
 613 * dummy buffer handling
 614 */
 615
 616static void *dummy_page[2];
 617
 618static void free_fake_buffer(void)
 619{
 620        if (fake_buffer) {
 621                int i;
 622                for (i = 0; i < 2; i++)
 623                        if (dummy_page[i]) {
 624                                free_page((unsigned long)dummy_page[i]);
 625                                dummy_page[i] = NULL;
 626                        }
 627        }
 628}
 629
 630static int alloc_fake_buffer(void)
 631{
 632        int i;
 633
 634        if (!fake_buffer)
 635                return 0;
 636        for (i = 0; i < 2; i++) {
 637                dummy_page[i] = (void *)get_zeroed_page(GFP_KERNEL);
 638                if (!dummy_page[i]) {
 639                        free_fake_buffer();
 640                        return -ENOMEM;
 641                }
 642        }
 643        return 0;
 644}
 645
 646static int dummy_pcm_copy(struct snd_pcm_substream *substream,
 647                          int channel, snd_pcm_uframes_t pos,
 648                          void __user *dst, snd_pcm_uframes_t count)
 649{
 650        return 0; /* do nothing */
 651}
 652
 653static int dummy_pcm_silence(struct snd_pcm_substream *substream,
 654                             int channel, snd_pcm_uframes_t pos,
 655                             snd_pcm_uframes_t count)
 656{
 657        return 0; /* do nothing */
 658}
 659
 660static struct page *dummy_pcm_page(struct snd_pcm_substream *substream,
 661                                   unsigned long offset)
 662{
 663        return virt_to_page(dummy_page[substream->stream]); /* the same page */
 664}
 665
 666static struct snd_pcm_ops dummy_pcm_ops = {
 667        .open =         dummy_pcm_open,
 668        .close =        dummy_pcm_close,
 669        .ioctl =        snd_pcm_lib_ioctl,
 670        .hw_params =    dummy_pcm_hw_params,
 671        .hw_free =      dummy_pcm_hw_free,
 672        .prepare =      dummy_pcm_prepare,
 673        .trigger =      dummy_pcm_trigger,
 674        .pointer =      dummy_pcm_pointer,
 675};
 676
 677static struct snd_pcm_ops dummy_pcm_ops_no_buf = {
 678        .open =         dummy_pcm_open,
 679        .close =        dummy_pcm_close,
 680        .ioctl =        snd_pcm_lib_ioctl,
 681        .hw_params =    dummy_pcm_hw_params,
 682        .hw_free =      dummy_pcm_hw_free,
 683        .prepare =      dummy_pcm_prepare,
 684        .trigger =      dummy_pcm_trigger,
 685        .pointer =      dummy_pcm_pointer,
 686        .copy =         dummy_pcm_copy,
 687        .silence =      dummy_pcm_silence,
 688        .page =         dummy_pcm_page,
 689};
 690
 691static int snd_card_dummy_pcm(struct snd_dummy *dummy, int device,
 692                              int substreams)
 693{
 694        struct snd_pcm *pcm;
 695        struct snd_pcm_ops *ops;
 696        int err;
 697
 698        err = snd_pcm_new(dummy->card, "Dummy PCM", device,
 699                               substreams, substreams, &pcm);
 700        if (err < 0)
 701                return err;
 702        dummy->pcm = pcm;
 703        if (fake_buffer)
 704                ops = &dummy_pcm_ops_no_buf;
 705        else
 706                ops = &dummy_pcm_ops;
 707        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, ops);
 708        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, ops);
 709        pcm->private_data = dummy;
 710        pcm->info_flags = 0;
 711        strcpy(pcm->name, "Dummy PCM");
 712        if (!fake_buffer) {
 713                snd_pcm_lib_preallocate_pages_for_all(pcm,
 714                        SNDRV_DMA_TYPE_CONTINUOUS,
 715                        snd_dma_continuous_data(GFP_KERNEL),
 716                        0, 64*1024);
 717        }
 718        return 0;
 719}
 720
 721/*
 722 * mixer interface
 723 */
 724
 725#define DUMMY_VOLUME(xname, xindex, addr) \
 726{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
 727  .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ, \
 728  .name = xname, .index = xindex, \
 729  .info = snd_dummy_volume_info, \
 730  .get = snd_dummy_volume_get, .put = snd_dummy_volume_put, \
 731  .private_value = addr, \
 732  .tlv = { .p = db_scale_dummy } }
 733
 734static int snd_dummy_volume_info(struct snd_kcontrol *kcontrol,
 735                                 struct snd_ctl_elem_info *uinfo)
 736{
 737        uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 738        uinfo->count = 2;
 739        uinfo->value.integer.min = -50;
 740        uinfo->value.integer.max = 100;
 741        return 0;
 742}
 743 
 744static int snd_dummy_volume_get(struct snd_kcontrol *kcontrol,
 745                                struct snd_ctl_elem_value *ucontrol)
 746{
 747        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 748        int addr = kcontrol->private_value;
 749
 750        spin_lock_irq(&dummy->mixer_lock);
 751        ucontrol->value.integer.value[0] = dummy->mixer_volume[addr][0];
 752        ucontrol->value.integer.value[1] = dummy->mixer_volume[addr][1];
 753        spin_unlock_irq(&dummy->mixer_lock);
 754        return 0;
 755}
 756
 757static int snd_dummy_volume_put(struct snd_kcontrol *kcontrol,
 758                                struct snd_ctl_elem_value *ucontrol)
 759{
 760        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 761        int change, addr = kcontrol->private_value;
 762        int left, right;
 763
 764        left = ucontrol->value.integer.value[0];
 765        if (left < -50)
 766                left = -50;
 767        if (left > 100)
 768                left = 100;
 769        right = ucontrol->value.integer.value[1];
 770        if (right < -50)
 771                right = -50;
 772        if (right > 100)
 773                right = 100;
 774        spin_lock_irq(&dummy->mixer_lock);
 775        change = dummy->mixer_volume[addr][0] != left ||
 776                 dummy->mixer_volume[addr][1] != right;
 777        dummy->mixer_volume[addr][0] = left;
 778        dummy->mixer_volume[addr][1] = right;
 779        spin_unlock_irq(&dummy->mixer_lock);
 780        return change;
 781}
 782
 783static const DECLARE_TLV_DB_SCALE(db_scale_dummy, -4500, 30, 0);
 784
 785#define DUMMY_CAPSRC(xname, xindex, addr) \
 786{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
 787  .info = snd_dummy_capsrc_info, \
 788  .get = snd_dummy_capsrc_get, .put = snd_dummy_capsrc_put, \
 789  .private_value = addr }
 790
 791#define snd_dummy_capsrc_info   snd_ctl_boolean_stereo_info
 792 
 793static int snd_dummy_capsrc_get(struct snd_kcontrol *kcontrol,
 794                                struct snd_ctl_elem_value *ucontrol)
 795{
 796        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 797        int addr = kcontrol->private_value;
 798
 799        spin_lock_irq(&dummy->mixer_lock);
 800        ucontrol->value.integer.value[0] = dummy->capture_source[addr][0];
 801        ucontrol->value.integer.value[1] = dummy->capture_source[addr][1];
 802        spin_unlock_irq(&dummy->mixer_lock);
 803        return 0;
 804}
 805
 806static int snd_dummy_capsrc_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
 807{
 808        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 809        int change, addr = kcontrol->private_value;
 810        int left, right;
 811
 812        left = ucontrol->value.integer.value[0] & 1;
 813        right = ucontrol->value.integer.value[1] & 1;
 814        spin_lock_irq(&dummy->mixer_lock);
 815        change = dummy->capture_source[addr][0] != left &&
 816                 dummy->capture_source[addr][1] != right;
 817        dummy->capture_source[addr][0] = left;
 818        dummy->capture_source[addr][1] = right;
 819        spin_unlock_irq(&dummy->mixer_lock);
 820        return change;
 821}
 822
 823static int snd_dummy_iobox_info(struct snd_kcontrol *kcontrol,
 824                                struct snd_ctl_elem_info *info)
 825{
 826        const char *const names[] = { "None", "CD Player" };
 827
 828        return snd_ctl_enum_info(info, 1, 2, names);
 829}
 830
 831static int snd_dummy_iobox_get(struct snd_kcontrol *kcontrol,
 832                               struct snd_ctl_elem_value *value)
 833{
 834        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 835
 836        value->value.enumerated.item[0] = dummy->iobox;
 837        return 0;
 838}
 839
 840static int snd_dummy_iobox_put(struct snd_kcontrol *kcontrol,
 841                               struct snd_ctl_elem_value *value)
 842{
 843        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 844        int changed;
 845
 846        if (value->value.enumerated.item[0] > 1)
 847                return -EINVAL;
 848
 849        changed = value->value.enumerated.item[0] != dummy->iobox;
 850        if (changed) {
 851                dummy->iobox = value->value.enumerated.item[0];
 852
 853                if (dummy->iobox) {
 854                        dummy->cd_volume_ctl->vd[0].access &=
 855                                ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 856                        dummy->cd_switch_ctl->vd[0].access &=
 857                                ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 858                } else {
 859                        dummy->cd_volume_ctl->vd[0].access |=
 860                                SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 861                        dummy->cd_switch_ctl->vd[0].access |=
 862                                SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 863                }
 864
 865                snd_ctl_notify(dummy->card, SNDRV_CTL_EVENT_MASK_INFO,
 866                               &dummy->cd_volume_ctl->id);
 867                snd_ctl_notify(dummy->card, SNDRV_CTL_EVENT_MASK_INFO,
 868                               &dummy->cd_switch_ctl->id);
 869        }
 870
 871        return changed;
 872}
 873
 874static struct snd_kcontrol_new snd_dummy_controls[] = {
 875DUMMY_VOLUME("Master Volume", 0, MIXER_ADDR_MASTER),
 876DUMMY_CAPSRC("Master Capture Switch", 0, MIXER_ADDR_MASTER),
 877DUMMY_VOLUME("Synth Volume", 0, MIXER_ADDR_SYNTH),
 878DUMMY_CAPSRC("Synth Capture Switch", 0, MIXER_ADDR_SYNTH),
 879DUMMY_VOLUME("Line Volume", 0, MIXER_ADDR_LINE),
 880DUMMY_CAPSRC("Line Capture Switch", 0, MIXER_ADDR_LINE),
 881DUMMY_VOLUME("Mic Volume", 0, MIXER_ADDR_MIC),
 882DUMMY_CAPSRC("Mic Capture Switch", 0, MIXER_ADDR_MIC),
 883DUMMY_VOLUME("CD Volume", 0, MIXER_ADDR_CD),
 884DUMMY_CAPSRC("CD Capture Switch", 0, MIXER_ADDR_CD),
 885{
 886        .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 887        .name  = "External I/O Box",
 888        .info  = snd_dummy_iobox_info,
 889        .get   = snd_dummy_iobox_get,
 890        .put   = snd_dummy_iobox_put,
 891},
 892};
 893
 894static int snd_card_dummy_new_mixer(struct snd_dummy *dummy)
 895{
 896        struct snd_card *card = dummy->card;
 897        struct snd_kcontrol *kcontrol;
 898        unsigned int idx;
 899        int err;
 900
 901        spin_lock_init(&dummy->mixer_lock);
 902        strcpy(card->mixername, "Dummy Mixer");
 903        dummy->iobox = 1;
 904
 905        for (idx = 0; idx < ARRAY_SIZE(snd_dummy_controls); idx++) {
 906                kcontrol = snd_ctl_new1(&snd_dummy_controls[idx], dummy);
 907                err = snd_ctl_add(card, kcontrol);
 908                if (err < 0)
 909                        return err;
 910                if (!strcmp(kcontrol->id.name, "CD Volume"))
 911                        dummy->cd_volume_ctl = kcontrol;
 912                else if (!strcmp(kcontrol->id.name, "CD Capture Switch"))
 913                        dummy->cd_switch_ctl = kcontrol;
 914
 915        }
 916        return 0;
 917}
 918
 919#if defined(CONFIG_SND_DEBUG) && defined(CONFIG_PROC_FS)
 920/*
 921 * proc interface
 922 */
 923static void print_formats(struct snd_dummy *dummy,
 924                          struct snd_info_buffer *buffer)
 925{
 926        int i;
 927
 928        for (i = 0; i < SNDRV_PCM_FORMAT_LAST; i++) {
 929                if (dummy->pcm_hw.formats & (1ULL << i))
 930                        snd_iprintf(buffer, " %s", snd_pcm_format_name(i));
 931        }
 932}
 933
 934static void print_rates(struct snd_dummy *dummy,
 935                        struct snd_info_buffer *buffer)
 936{
 937        static int rates[] = {
 938                5512, 8000, 11025, 16000, 22050, 32000, 44100, 48000,
 939                64000, 88200, 96000, 176400, 192000,
 940        };
 941        int i;
 942
 943        if (dummy->pcm_hw.rates & SNDRV_PCM_RATE_CONTINUOUS)
 944                snd_iprintf(buffer, " continuous");
 945        if (dummy->pcm_hw.rates & SNDRV_PCM_RATE_KNOT)
 946                snd_iprintf(buffer, " knot");
 947        for (i = 0; i < ARRAY_SIZE(rates); i++)
 948                if (dummy->pcm_hw.rates & (1 << i))
 949                        snd_iprintf(buffer, " %d", rates[i]);
 950}
 951
 952#define get_dummy_int_ptr(dummy, ofs) \
 953        (unsigned int *)((char *)&((dummy)->pcm_hw) + (ofs))
 954#define get_dummy_ll_ptr(dummy, ofs) \
 955        (unsigned long long *)((char *)&((dummy)->pcm_hw) + (ofs))
 956
 957struct dummy_hw_field {
 958        const char *name;
 959        const char *format;
 960        unsigned int offset;
 961        unsigned int size;
 962};
 963#define FIELD_ENTRY(item, fmt) {                   \
 964        .name = #item,                             \
 965        .format = fmt,                             \
 966        .offset = offsetof(struct snd_pcm_hardware, item), \
 967        .size = sizeof(dummy_pcm_hardware.item) }
 968
 969static struct dummy_hw_field fields[] = {
 970        FIELD_ENTRY(formats, "%#llx"),
 971        FIELD_ENTRY(rates, "%#x"),
 972        FIELD_ENTRY(rate_min, "%d"),
 973        FIELD_ENTRY(rate_max, "%d"),
 974        FIELD_ENTRY(channels_min, "%d"),
 975        FIELD_ENTRY(channels_max, "%d"),
 976        FIELD_ENTRY(buffer_bytes_max, "%ld"),
 977        FIELD_ENTRY(period_bytes_min, "%ld"),
 978        FIELD_ENTRY(period_bytes_max, "%ld"),
 979        FIELD_ENTRY(periods_min, "%d"),
 980        FIELD_ENTRY(periods_max, "%d"),
 981};
 982
 983static void dummy_proc_read(struct snd_info_entry *entry,
 984                            struct snd_info_buffer *buffer)
 985{
 986        struct snd_dummy *dummy = entry->private_data;
 987        int i;
 988
 989        for (i = 0; i < ARRAY_SIZE(fields); i++) {
 990                snd_iprintf(buffer, "%s ", fields[i].name);
 991                if (fields[i].size == sizeof(int))
 992                        snd_iprintf(buffer, fields[i].format,
 993                                *get_dummy_int_ptr(dummy, fields[i].offset));
 994                else
 995                        snd_iprintf(buffer, fields[i].format,
 996                                *get_dummy_ll_ptr(dummy, fields[i].offset));
 997                if (!strcmp(fields[i].name, "formats"))
 998                        print_formats(dummy, buffer);
 999                else if (!strcmp(fields[i].name, "rates"))
1000                        print_rates(dummy, buffer);
1001                snd_iprintf(buffer, "\n");
1002        }
1003}
1004
1005static void dummy_proc_write(struct snd_info_entry *entry,
1006                             struct snd_info_buffer *buffer)
1007{
1008        struct snd_dummy *dummy = entry->private_data;
1009        char line[64];
1010
1011        while (!snd_info_get_line(buffer, line, sizeof(line))) {
1012                char item[20];
1013                const char *ptr;
1014                unsigned long long val;
1015                int i;
1016
1017                ptr = snd_info_get_str(item, line, sizeof(item));
1018                for (i = 0; i < ARRAY_SIZE(fields); i++) {
1019                        if (!strcmp(item, fields[i].name))
1020                                break;
1021                }
1022                if (i >= ARRAY_SIZE(fields))
1023                        continue;
1024                snd_info_get_str(item, ptr, sizeof(item));
1025                if (strict_strtoull(item, 0, &val))
1026                        continue;
1027                if (fields[i].size == sizeof(int))
1028                        *get_dummy_int_ptr(dummy, fields[i].offset) = val;
1029                else
1030                        *get_dummy_ll_ptr(dummy, fields[i].offset) = val;
1031        }
1032}
1033
1034static void dummy_proc_init(struct snd_dummy *chip)
1035{
1036        struct snd_info_entry *entry;
1037
1038        if (!snd_card_proc_new(chip->card, "dummy_pcm", &entry)) {
1039                snd_info_set_text_ops(entry, chip, dummy_proc_read);
1040                entry->c.text.write = dummy_proc_write;
1041                entry->mode |= S_IWUSR;
1042                entry->private_data = chip;
1043        }
1044}
1045#else
1046#define dummy_proc_init(x)
1047#endif /* CONFIG_SND_DEBUG && CONFIG_PROC_FS */
1048
1049static int snd_dummy_probe(struct platform_device *devptr)
1050{
1051        struct snd_card *card;
1052        struct snd_dummy *dummy;
1053        struct dummy_model *m = NULL, **mdl;
1054        int idx, err;
1055        int dev = devptr->id;
1056
1057        err = snd_card_create(index[dev], id[dev], THIS_MODULE,
1058                              sizeof(struct snd_dummy), &card);
1059        if (err < 0)
1060                return err;
1061        dummy = card->private_data;
1062        dummy->card = card;
1063        for (mdl = dummy_models; *mdl && model[dev]; mdl++) {
1064                if (strcmp(model[dev], (*mdl)->name) == 0) {
1065                        printk(KERN_INFO
1066                                "snd-dummy: Using model '%s' for card %i\n",
1067                                (*mdl)->name, card->number);
1068                        m = dummy->model = *mdl;
1069                        break;
1070                }
1071        }
1072        for (idx = 0; idx < MAX_PCM_DEVICES && idx < pcm_devs[dev]; idx++) {
1073                if (pcm_substreams[dev] < 1)
1074                        pcm_substreams[dev] = 1;
1075                if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
1076                        pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
1077                err = snd_card_dummy_pcm(dummy, idx, pcm_substreams[dev]);
1078                if (err < 0)
1079                        goto __nodev;
1080        }
1081
1082        dummy->pcm_hw = dummy_pcm_hardware;
1083        if (m) {
1084                if (m->formats)
1085                        dummy->pcm_hw.formats = m->formats;
1086                if (m->buffer_bytes_max)
1087                        dummy->pcm_hw.buffer_bytes_max = m->buffer_bytes_max;
1088                if (m->period_bytes_min)
1089                        dummy->pcm_hw.period_bytes_min = m->period_bytes_min;
1090                if (m->period_bytes_max)
1091                        dummy->pcm_hw.period_bytes_max = m->period_bytes_max;
1092                if (m->periods_min)
1093                        dummy->pcm_hw.periods_min = m->periods_min;
1094                if (m->periods_max)
1095                        dummy->pcm_hw.periods_max = m->periods_max;
1096                if (m->rates)
1097                        dummy->pcm_hw.rates = m->rates;
1098                if (m->rate_min)
1099                        dummy->pcm_hw.rate_min = m->rate_min;
1100                if (m->rate_max)
1101                        dummy->pcm_hw.rate_max = m->rate_max;
1102                if (m->channels_min)
1103                        dummy->pcm_hw.channels_min = m->channels_min;
1104                if (m->channels_max)
1105                        dummy->pcm_hw.channels_max = m->channels_max;
1106        }
1107
1108        err = snd_card_dummy_new_mixer(dummy);
1109        if (err < 0)
1110                goto __nodev;
1111        strcpy(card->driver, "Dummy");
1112        strcpy(card->shortname, "Dummy");
1113        sprintf(card->longname, "Dummy %i", dev + 1);
1114
1115        dummy_proc_init(dummy);
1116
1117        snd_card_set_dev(card, &devptr->dev);
1118
1119        err = snd_card_register(card);
1120        if (err == 0) {
1121                platform_set_drvdata(devptr, card);
1122                return 0;
1123        }
1124      __nodev:
1125        snd_card_free(card);
1126        return err;
1127}
1128
1129static int snd_dummy_remove(struct platform_device *devptr)
1130{
1131        snd_card_free(platform_get_drvdata(devptr));
1132        platform_set_drvdata(devptr, NULL);
1133        return 0;
1134}
1135
1136#ifdef CONFIG_PM_SLEEP
1137static int snd_dummy_suspend(struct device *pdev)
1138{
1139        struct snd_card *card = dev_get_drvdata(pdev);
1140        struct snd_dummy *dummy = card->private_data;
1141
1142        snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
1143        snd_pcm_suspend_all(dummy->pcm);
1144        return 0;
1145}
1146        
1147static int snd_dummy_resume(struct device *pdev)
1148{
1149        struct snd_card *card = dev_get_drvdata(pdev);
1150
1151        snd_power_change_state(card, SNDRV_CTL_POWER_D0);
1152        return 0;
1153}
1154
1155static SIMPLE_DEV_PM_OPS(snd_dummy_pm, snd_dummy_suspend, snd_dummy_resume);
1156#define SND_DUMMY_PM_OPS        &snd_dummy_pm
1157#else
1158#define SND_DUMMY_PM_OPS        NULL
1159#endif
1160
1161#define SND_DUMMY_DRIVER        "snd_dummy"
1162
1163static struct platform_driver snd_dummy_driver = {
1164        .probe          = snd_dummy_probe,
1165        .remove         = snd_dummy_remove,
1166        .driver         = {
1167                .name   = SND_DUMMY_DRIVER,
1168                .owner  = THIS_MODULE,
1169                .pm     = SND_DUMMY_PM_OPS,
1170        },
1171};
1172
1173static void snd_dummy_unregister_all(void)
1174{
1175        int i;
1176
1177        for (i = 0; i < ARRAY_SIZE(devices); ++i)
1178                platform_device_unregister(devices[i]);
1179        platform_driver_unregister(&snd_dummy_driver);
1180        free_fake_buffer();
1181}
1182
1183static int __init alsa_card_dummy_init(void)
1184{
1185        int i, cards, err;
1186
1187        err = platform_driver_register(&snd_dummy_driver);
1188        if (err < 0)
1189                return err;
1190
1191        err = alloc_fake_buffer();
1192        if (err < 0) {
1193                platform_driver_unregister(&snd_dummy_driver);
1194                return err;
1195        }
1196
1197        cards = 0;
1198        for (i = 0; i < SNDRV_CARDS; i++) {
1199                struct platform_device *device;
1200                if (! enable[i])
1201                        continue;
1202                device = platform_device_register_simple(SND_DUMMY_DRIVER,
1203                                                         i, NULL, 0);
1204                if (IS_ERR(device))
1205                        continue;
1206                if (!platform_get_drvdata(device)) {
1207                        platform_device_unregister(device);
1208                        continue;
1209                }
1210                devices[i] = device;
1211                cards++;
1212        }
1213        if (!cards) {
1214#ifdef MODULE
1215                printk(KERN_ERR "Dummy soundcard not found or device busy\n");
1216#endif
1217                snd_dummy_unregister_all();
1218                return -ENODEV;
1219        }
1220        return 0;
1221}
1222
1223static void __exit alsa_card_dummy_exit(void)
1224{
1225        snd_dummy_unregister_all();
1226}
1227
1228module_init(alsa_card_dummy_init)
1229module_exit(alsa_card_dummy_exit)
1230