kernel/sound/drivers/dummy.c

   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
  39 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
  40 MODULE_DESCRIPTION("Dummy soundcard (/dev/null)");
  41 MODULE_LICENSE("GPL");
  42 MODULE_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
  61 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;      /* Index 0-MAX */
  62 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;       /* ID for this card */
  63 static bool enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
  64 static char *model[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = NULL};
  65 static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
  66 static 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
  69 static bool hrtimer = 1;
  70 #endif
  71 static bool fake_buffer = 1;
  72
  73 module_param_array(index, int, NULL, 0444);
  74 MODULE_PARM_DESC(index, "Index value for dummy soundcard.");
  75 module_param_array(id, charp, NULL, 0444);
  76 MODULE_PARM_DESC(id, "ID string for dummy soundcard.");
  77 module_param_array(enable, bool, NULL, 0444);
  78 MODULE_PARM_DESC(enable, "Enable this dummy soundcard.");
  79 module_param_array(model, charp, NULL, 0444);
  80 MODULE_PARM_DESC(model, "Soundcard model.");
  81 module_param_array(pcm_devs, int, NULL, 0444);
  82 MODULE_PARM_DESC(pcm_devs, "PCM devices # (0-4) for dummy driver.");
  83 module_param_array(pcm_substreams, int, NULL, 0444);
  84 MODULE_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.");
  87 module_param(fake_buffer, bool, 0444);
  88 MODULE_PARM_DESC(fake_buffer, "Fake buffer allocations.");
  89 #ifdef CONFIG_HIGH_RES_TIMERS
  90 module_param(hrtimer, bool, 0644);
  91 MODULE_PARM_DESC(hrtimer, "Use hrtimer as the timer source.");
  92 #endif
  93
  94 static 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
 103 struct 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
 112 #define get_dummy_ops(substream) \
 113         (*(const struct dummy_timer_ops **)(substream)->runtime->private_data)
 114
 115 struct dummy_model {
 116         const char *name;
 117         int (*playback_constraints)(struct snd_pcm_runtime *runtime);
 118         int (*capture_constraints)(struct snd_pcm_runtime *runtime);
 119         u64 formats;
 120         size_t buffer_bytes_max;
 121         size_t period_bytes_min;
 122         size_t period_bytes_max;
 123         unsigned int periods_min;
 124         unsigned int periods_max;
 125         unsigned int rates;
 126         unsigned int rate_min;
 127         unsigned int rate_max;
 128         unsigned int channels_min;
 129         unsigned int channels_max;
 130 };
 131
 132 struct snd_dummy {
 133         struct snd_card *card;
 134         struct dummy_model *model;
 135         struct snd_pcm *pcm;
 136         struct snd_pcm_hardware pcm_hw;
 137         spinlock_t mixer_lock;
 138         int mixer_volume[MIXER_ADDR_LAST+1][2];
 139         int capture_source[MIXER_ADDR_LAST+1][2];
 140         int iobox;
 141         struct snd_kcontrol *cd_volume_ctl;
 142         struct snd_kcontrol *cd_switch_ctl;
 143 };
 144
 145 /*
 146  * card models
 147  */
 148
 149 static int emu10k1_playback_constraints(struct snd_pcm_runtime *runtime)
 150 {
 151         int err;
 152         err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 153         if (err < 0)
 154                 return err;
 155         err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX);
 156         if (err < 0)
 157                 return err;
 158         return 0;
 159 }
 160
 161 static struct dummy_model model_emu10k1 = {
 162         .name = "emu10k1",
 163         .playback_constraints = emu10k1_playback_constraints,
 164         .buffer_bytes_max = 128 * 1024,
 165 };
 166
 167 static struct dummy_model model_rme9652 = {
 168         .name = "rme9652",
 169         .buffer_bytes_max = 26 * 64 * 1024,
 170         .formats = SNDRV_PCM_FMTBIT_S32_LE,
 171         .channels_min = 26,
 172         .channels_max = 26,
 173         .periods_min = 2,
 174         .periods_max = 2,
 175 };
 176
 177 static struct dummy_model model_ice1712 = {
 178         .name = "ice1712",
 179         .buffer_bytes_max = 256 * 1024,
 180         .formats = SNDRV_PCM_FMTBIT_S32_LE,
 181         .channels_min = 10,
 182         .channels_max = 10,
 183         .periods_min = 1,
 184         .periods_max = 1024,
 185 };
 186
 187 static struct dummy_model model_uda1341 = {
 188         .name = "uda1341",
 189         .buffer_bytes_max = 16380,
 190         .formats = SNDRV_PCM_FMTBIT_S16_LE,
 191         .channels_min = 2,
 192         .channels_max = 2,
 193         .periods_min = 2,
 194         .periods_max = 255,
 195 };
 196
 197 static struct dummy_model model_ac97 = {
 198         .name = "ac97",
 199         .formats = SNDRV_PCM_FMTBIT_S16_LE,
 200         .channels_min = 2,
 201         .channels_max = 2,
 202         .rates = SNDRV_PCM_RATE_48000,
 203         .rate_min = 48000,
 204         .rate_max = 48000,
 205 };
 206
 207 static struct dummy_model model_ca0106 = {
 208         .name = "ca0106",
 209         .formats = SNDRV_PCM_FMTBIT_S16_LE,
 210         .buffer_bytes_max = ((65536-64)*8),
 211         .period_bytes_max = (65536-64),
 212         .periods_min = 2,
 213         .periods_max = 8,
 214         .channels_min = 2,
 215         .channels_max = 2,
 216         .rates = SNDRV_PCM_RATE_48000|SNDRV_PCM_RATE_96000|SNDRV_PCM_RATE_192000,
 217         .rate_min = 48000,
 218         .rate_max = 192000,
 219 };
 220
 221 static struct dummy_model *dummy_models[] = {
 222         &model_emu10k1,
 223         &model_rme9652,
 224         &model_ice1712,
 225         &model_uda1341,
 226         &model_ac97,
 227         &model_ca0106,
 228         NULL
 229 };
 230
 231 /*
 232  * system timer interface
 233  */
 234
 235 struct dummy_systimer_pcm {
 236         /* ops must be the first item */
 237         const struct dummy_timer_ops *timer_ops;
 238         spinlock_t lock;
 239         struct timer_list timer;
 240         unsigned long base_time;
 241         unsigned int frac_pos;  /* fractional sample position (based HZ) */
 242         unsigned int frac_period_rest;
 243         unsigned int frac_buffer_size;  /* buffer_size * HZ */
 244         unsigned int frac_period_size;  /* period_size * HZ */
 245         unsigned int rate;
 246         int elapsed;
 247         struct snd_pcm_substream *substream;
 248 };
 249
 250 static void dummy_systimer_rearm(struct dummy_systimer_pcm *dpcm)
 251 {
 252         mod_timer(&dpcm->timer, jiffies +
 253                 (dpcm->frac_period_rest + dpcm->rate - 1) / dpcm->rate);
 254 }
 255
 256 static void dummy_systimer_update(struct dummy_systimer_pcm *dpcm)
 257 {
 258         unsigned long delta;
 259
 260         delta = jiffies - dpcm->base_time;
 261         if (!delta)
 262                 return;
 263         dpcm->base_time += delta;
 264         delta *= dpcm->rate;
 265         dpcm->frac_pos += delta;
 266         while (dpcm->frac_pos >= dpcm->frac_buffer_size)
 267                 dpcm->frac_pos -= dpcm->frac_buffer_size;
 268         while (dpcm->frac_period_rest <= delta) {
 269                 dpcm->elapsed++;
 270                 dpcm->frac_period_rest += dpcm->frac_period_size;
 271         }
 272         dpcm->frac_period_rest -= delta;
 273 }
 274
 275 static int dummy_systimer_start(struct snd_pcm_substream *substream)
 276 {
 277         struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 278         spin_lock(&dpcm->lock);
 279         dpcm->base_time = jiffies;
 280         dummy_systimer_rearm(dpcm);
 281         spin_unlock(&dpcm->lock);
 282         return 0;
 283 }
 284
 285 static int dummy_systimer_stop(struct snd_pcm_substream *substream)
 286 {
 287         struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 288         spin_lock(&dpcm->lock);
 289         del_timer(&dpcm->timer);
 290         spin_unlock(&dpcm->lock);
 291         return 0;
 292 }
 293
 294 static int dummy_systimer_prepare(struct snd_pcm_substream *substream)
 295 {
 296         struct snd_pcm_runtime *runtime = substream->runtime;
 297         struct dummy_systimer_pcm *dpcm = runtime->private_data;
 298
 299         dpcm->frac_pos = 0;
 300         dpcm->rate = runtime->rate;
 301         dpcm->frac_buffer_size = runtime->buffer_size * HZ;
 302         dpcm->frac_period_size = runtime->period_size * HZ;
 303         dpcm->frac_period_rest = dpcm->frac_period_size;
 304         dpcm->elapsed = 0;
 305
 306         return 0;
 307 }
 308
 309 static void dummy_systimer_callback(unsigned long data)
 310 {
 311         struct dummy_systimer_pcm *dpcm = (struct dummy_systimer_pcm *)data;
 312         unsigned long flags;
 313         int elapsed = 0;
 314
 315         spin_lock_irqsave(&dpcm->lock, flags);
 316         dummy_systimer_update(dpcm);
 317         dummy_systimer_rearm(dpcm);
 318         elapsed = dpcm->elapsed;
 319         dpcm->elapsed = 0;
 320         spin_unlock_irqrestore(&dpcm->lock, flags);
 321         if (elapsed)
 322                 snd_pcm_period_elapsed(dpcm->substream);
 323 }
 324
 325 static snd_pcm_uframes_t
 326 dummy_systimer_pointer(struct snd_pcm_substream *substream)
 327 {
 328         struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 329         snd_pcm_uframes_t pos;
 330
 331         spin_lock(&dpcm->lock);
 332         dummy_systimer_update(dpcm);
 333         pos = dpcm->frac_pos / HZ;
 334         spin_unlock(&dpcm->lock);
 335         return pos;
 336 }
 337
 338 static int dummy_systimer_create(struct snd_pcm_substream *substream)
 339 {
 340         struct dummy_systimer_pcm *dpcm;
 341
 342         dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 343         if (!dpcm)
 344                 return -ENOMEM;
 345         substream->runtime->private_data = dpcm;
 346         setup_timer(&dpcm->timer, dummy_systimer_callback,
 347                         (unsigned long) dpcm);
 348         spin_lock_init(&dpcm->lock);
 349         dpcm->substream = substream;
 350         return 0;
 351 }
 352
 353 static void dummy_systimer_free(struct snd_pcm_substream *substream)
 354 {
 355         kfree(substream->runtime->private_data);
 356 }
 357
 358 static struct dummy_timer_ops dummy_systimer_ops = {
 359         .create =       dummy_systimer_create,
 360         .free =         dummy_systimer_free,
 361         .prepare =      dummy_systimer_prepare,
 362         .start =        dummy_systimer_start,
 363         .stop =         dummy_systimer_stop,
 364         .pointer =      dummy_systimer_pointer,
 365 };
 366
 367 #ifdef CONFIG_HIGH_RES_TIMERS
 368 /*
 369  * hrtimer interface
 370  */
 371
 372 struct dummy_hrtimer_pcm {
 373         /* ops must be the first item */
 374         const struct dummy_timer_ops *timer_ops;
 375         ktime_t base_time;
 376         ktime_t period_time;
 377         atomic_t running;
 378         struct hrtimer timer;
 379         struct tasklet_struct tasklet;
 380         struct snd_pcm_substream *substream;
 381 };
 382
 383 static void dummy_hrtimer_pcm_elapsed(unsigned long priv)
 384 {
 385         struct dummy_hrtimer_pcm *dpcm = (struct dummy_hrtimer_pcm *)priv;
 386         if (atomic_read(&dpcm->running))
 387                 snd_pcm_period_elapsed(dpcm->substream);
 388 }
 389
 390 static enum hrtimer_restart dummy_hrtimer_callback(struct hrtimer *timer)
 391 {
 392         struct dummy_hrtimer_pcm *dpcm;
 393
 394         dpcm = container_of(timer, struct dummy_hrtimer_pcm, timer);
 395         if (!atomic_read(&dpcm->running))
 396                 return HRTIMER_NORESTART;
 397         tasklet_schedule(&dpcm->tasklet);
 398         hrtimer_forward_now(timer, dpcm->period_time);
 399         return HRTIMER_RESTART;
 400 }
 401
 402 static int dummy_hrtimer_start(struct snd_pcm_substream *substream)
 403 {
 404         struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 405
 406         dpcm->base_time = hrtimer_cb_get_time(&dpcm->timer);
 407         hrtimer_start(&dpcm->timer, dpcm->period_time, HRTIMER_MODE_REL);
 408         atomic_set(&dpcm->running, 1);
 409         return 0;
 410 }
 411
 412 static int dummy_hrtimer_stop(struct snd_pcm_substream *substream)
 413 {
 414         struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 415
 416         atomic_set(&dpcm->running, 0);
 417         hrtimer_cancel(&dpcm->timer);
 418         return 0;
 419 }
 420
 421 static inline void dummy_hrtimer_sync(struct dummy_hrtimer_pcm *dpcm)
 422 {
 423         tasklet_kill(&dpcm->tasklet);
 424 }
 425
 426 static snd_pcm_uframes_t
 427 dummy_hrtimer_pointer(struct snd_pcm_substream *substream)
 428 {
 429         struct snd_pcm_runtime *runtime = substream->runtime;
 430         struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 431         u64 delta;
 432         u32 pos;
 433
 434         delta = ktime_us_delta(hrtimer_cb_get_time(&dpcm->timer),
 435                                dpcm->base_time);
 436         delta = div_u64(delta * runtime->rate + 999999, 1000000);
 437         div_u64_rem(delta, runtime->buffer_size, &pos);
 438         return pos;
 439 }
 440
 441 static int dummy_hrtimer_prepare(struct snd_pcm_substream *substream)
 442 {
 443         struct snd_pcm_runtime *runtime = substream->runtime;
 444         struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 445         unsigned int period, rate;
 446         long sec;
 447         unsigned long nsecs;
 448
 449         dummy_hrtimer_sync(dpcm);
 450         period = runtime->period_size;
 451         rate = runtime->rate;
 452         sec = period / rate;
 453         period %= rate;
 454         nsecs = div_u64((u64)period * 1000000000UL + rate - 1, rate);
 455         dpcm->period_time = ktime_set(sec, nsecs);
 456
 457         return 0;
 458 }
 459
 460 static int dummy_hrtimer_create(struct snd_pcm_substream *substream)
 461 {
 462         struct dummy_hrtimer_pcm *dpcm;
 463
 464         dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 465         if (!dpcm)
 466                 return -ENOMEM;
 467         substream->runtime->private_data = dpcm;
 468         hrtimer_init(&dpcm->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 469         dpcm->timer.function = dummy_hrtimer_callback;
 470         dpcm->substream = substream;
 471         atomic_set(&dpcm->running, 0);
 472         tasklet_init(&dpcm->tasklet, dummy_hrtimer_pcm_elapsed,
 473                      (unsigned long)dpcm);
 474         return 0;
 475 }
 476
 477 static void dummy_hrtimer_free(struct snd_pcm_substream *substream)
 478 {
 479         struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 480         dummy_hrtimer_sync(dpcm);
 481         kfree(dpcm);
 482 }
 483
 484 static struct dummy_timer_ops dummy_hrtimer_ops = {
 485         .create =       dummy_hrtimer_create,
 486         .free =         dummy_hrtimer_free,
 487         .prepare =      dummy_hrtimer_prepare,
 488         .start =        dummy_hrtimer_start,
 489         .stop =         dummy_hrtimer_stop,
 490         .pointer =      dummy_hrtimer_pointer,
 491 };
 492
 493 #endif /* CONFIG_HIGH_RES_TIMERS */
 494
 495 /*
 496  * PCM interface
 497  */
 498
 499 static int dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 500 {
 501         switch (cmd) {
 502         case SNDRV_PCM_TRIGGER_START:
 503         case SNDRV_PCM_TRIGGER_RESUME:
 504                 return get_dummy_ops(substream)->start(substream);
 505         case SNDRV_PCM_TRIGGER_STOP:
 506         case SNDRV_PCM_TRIGGER_SUSPEND:
 507                 return get_dummy_ops(substream)->stop(substream);
 508         }
 509         return -EINVAL;
 510 }
 511
 512 static int dummy_pcm_prepare(struct snd_pcm_substream *substream)
 513 {
 514         return get_dummy_ops(substream)->prepare(substream);
 515 }
 516
 517 static snd_pcm_uframes_t dummy_pcm_pointer(struct snd_pcm_substream *substream)
 518 {
 519         return get_dummy_ops(substream)->pointer(substream);
 520 }
 521
 522 static struct snd_pcm_hardware dummy_pcm_hardware = {
 523         .info =                 (SNDRV_PCM_INFO_MMAP |
 524                                  SNDRV_PCM_INFO_INTERLEAVED |
 525                                  SNDRV_PCM_INFO_RESUME |
 526                                  SNDRV_PCM_INFO_MMAP_VALID),
 527         .formats =              USE_FORMATS,
 528         .rates =                USE_RATE,
 529         .rate_min =             USE_RATE_MIN,
 530         .rate_max =             USE_RATE_MAX,
 531         .channels_min =         USE_CHANNELS_MIN,
 532         .channels_max =         USE_CHANNELS_MAX,
 533         .buffer_bytes_max =     MAX_BUFFER_SIZE,
 534         .period_bytes_min =     MIN_PERIOD_SIZE,
 535         .period_bytes_max =     MAX_PERIOD_SIZE,
 536         .periods_min =          USE_PERIODS_MIN,
 537         .periods_max =          USE_PERIODS_MAX,
 538         .fifo_size =            0,
 539 };
 540
 541 static int dummy_pcm_hw_params(struct snd_pcm_substream *substream,
 542                                struct snd_pcm_hw_params *hw_params)
 543 {
 544         if (fake_buffer) {
 545                 /* runtime->dma_bytes has to be set manually to allow mmap */
 546                 substream->runtime->dma_bytes = params_buffer_bytes(hw_params);
 547                 return 0;
 548         }
 549         return snd_pcm_lib_malloc_pages(substream,
 550                                         params_buffer_bytes(hw_params));
 551 }
 552
 553 static int dummy_pcm_hw_free(struct snd_pcm_substream *substream)
 554 {
 555         if (fake_buffer)
 556                 return 0;
 557         return snd_pcm_lib_free_pages(substream);
 558 }
 559
 560 static int dummy_pcm_open(struct snd_pcm_substream *substream)
 561 {
 562         struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 563         struct dummy_model *model = dummy->model;
 564         struct snd_pcm_runtime *runtime = substream->runtime;
 565         const struct dummy_timer_ops *ops;
 566         int err;
 567
 568         ops = &dummy_systimer_ops;
 569 #ifdef CONFIG_HIGH_RES_TIMERS
 570         if (hrtimer)
 571                 ops = &dummy_hrtimer_ops;
 572 #endif
 573
 574         err = ops->create(substream);
 575         if (err < 0)
 576                 return err;
 577         get_dummy_ops(substream) = ops;
 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                 get_dummy_ops(substream)->free(substream);
 600                 return err;
 601         }
 602         return 0;
 603 }
 604
 605 static int dummy_pcm_close(struct snd_pcm_substream *substream)
 606 {
 607         get_dummy_ops(substream)->free(substream);
 608         return 0;
 609 }
 610
 611 /*
 612  * dummy buffer handling
 613  */
 614
 615 static void *dummy_page[2];
 616
 617 static void free_fake_buffer(void)
 618 {
 619         if (fake_buffer) {
 620                 int i;
 621                 for (i = 0; i < 2; i++)
 622                         if (dummy_page[i]) {
 623                                 free_page((unsigned long)dummy_page[i]);
 624                                 dummy_page[i] = NULL;
 625                         }
 626         }
 627 }
 628
 629 static int alloc_fake_buffer(void)
 630 {
 631         int i;
 632
 633         if (!fake_buffer)
 634                 return 0;
 635         for (i = 0; i < 2; i++) {
 636                 dummy_page[i] = (void *)get_zeroed_page(GFP_KERNEL);
 637                 if (!dummy_page[i]) {
 638                         free_fake_buffer();
 639                         return -ENOMEM;
 640                 }
 641         }
 642         return 0;
 643 }
 644
 645 static int dummy_pcm_copy(struct snd_pcm_substream *substream,
 646                           int channel, snd_pcm_uframes_t pos,
 647                           void __user *dst, snd_pcm_uframes_t count)
 648 {
 649         return 0; /* do nothing */
 650 }
 651
 652 static int dummy_pcm_silence(struct snd_pcm_substream *substream,
 653                              int channel, snd_pcm_uframes_t pos,
 654                              snd_pcm_uframes_t count)
 655 {
 656         return 0; /* do nothing */
 657 }
 658
 659 static struct page *dummy_pcm_page(struct snd_pcm_substream *substream,
 660                                    unsigned long offset)
 661 {
 662         return virt_to_page(dummy_page[substream->stream]); /* the same page */
 663 }
 664
 665 static struct snd_pcm_ops dummy_pcm_ops = {
 666         .open =         dummy_pcm_open,
 667         .close =        dummy_pcm_close,
 668         .ioctl =        snd_pcm_lib_ioctl,
 669         .hw_params =    dummy_pcm_hw_params,
 670         .hw_free =      dummy_pcm_hw_free,
 671         .prepare =      dummy_pcm_prepare,
 672         .trigger =      dummy_pcm_trigger,
 673         .pointer =      dummy_pcm_pointer,
 674 };
 675
 676 static struct snd_pcm_ops dummy_pcm_ops_no_buf = {
 677         .open =         dummy_pcm_open,
 678         .close =        dummy_pcm_close,
 679         .ioctl =        snd_pcm_lib_ioctl,
 680         .hw_params =    dummy_pcm_hw_params,
 681         .hw_free =      dummy_pcm_hw_free,
 682         .prepare =      dummy_pcm_prepare,
 683         .trigger =      dummy_pcm_trigger,
 684         .pointer =      dummy_pcm_pointer,
 685         .copy =         dummy_pcm_copy,
 686         .silence =      dummy_pcm_silence,
 687         .page =         dummy_pcm_page,
 688 };
 689
 690 static int snd_card_dummy_pcm(struct snd_dummy *dummy, int device,
 691                               int substreams)
 692 {
 693         struct snd_pcm *pcm;
 694         struct snd_pcm_ops *ops;
 695         int err;
 696
 697         err = snd_pcm_new(dummy->card, "Dummy PCM", device,
 698                                substreams, substreams, &pcm);
 699         if (err < 0)
 700                 return err;
 701         dummy->pcm = pcm;
 702         if (fake_buffer)
 703                 ops = &dummy_pcm_ops_no_buf;
 704         else
 705                 ops = &dummy_pcm_ops;
 706         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, ops);
 707         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, ops);
 708         pcm->private_data = dummy;
 709         pcm->info_flags = 0;
 710         strcpy(pcm->name, "Dummy PCM");
 711         if (!fake_buffer) {
 712                 snd_pcm_lib_preallocate_pages_for_all(pcm,
 713                         SNDRV_DMA_TYPE_CONTINUOUS,
 714                         snd_dma_continuous_data(GFP_KERNEL),
 715                         0, 64*1024);
 716         }
 717         return 0;
 718 }
 719
 720 /*
 721  * mixer interface
 722  */
 723
 724 #define DUMMY_VOLUME(xname, xindex, addr) \
 725 { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
 726   .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ, \
 727   .name = xname, .index = xindex, \
 728   .info = snd_dummy_volume_info, \
 729   .get = snd_dummy_volume_get, .put = snd_dummy_volume_put, \
 730   .private_value = addr, \
 731   .tlv = { .p = db_scale_dummy } }
 732
 733 static int snd_dummy_volume_info(struct snd_kcontrol *kcontrol,
 734                                  struct snd_ctl_elem_info *uinfo)
 735 {
 736         uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 737         uinfo->count = 2;
 738         uinfo->value.integer.min = -50;
 739         uinfo->value.integer.max = 100;
 740         return 0;
 741 }
 742
 743 static int snd_dummy_volume_get(struct snd_kcontrol *kcontrol,
 744                                 struct snd_ctl_elem_value *ucontrol)
 745 {
 746         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 747         int addr = kcontrol->private_value;
 748
 749         spin_lock_irq(&dummy->mixer_lock);
 750         ucontrol->value.integer.value[0] = dummy->mixer_volume[addr][0];
 751         ucontrol->value.integer.value[1] = dummy->mixer_volume[addr][1];
 752         spin_unlock_irq(&dummy->mixer_lock);
 753         return 0;
 754 }
 755
 756 static int snd_dummy_volume_put(struct snd_kcontrol *kcontrol,
 757                                 struct snd_ctl_elem_value *ucontrol)
 758 {
 759         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 760         int change, addr = kcontrol->private_value;
 761         int left, right;
 762
 763         left = ucontrol->value.integer.value[0];
 764         if (left < -50)
 765                 left = -50;
 766         if (left > 100)
 767                 left = 100;
 768         right = ucontrol->value.integer.value[1];
 769         if (right < -50)
 770                 right = -50;
 771         if (right > 100)
 772                 right = 100;
 773         spin_lock_irq(&dummy->mixer_lock);
 774         change = dummy->mixer_volume[addr][0] != left ||
 775                  dummy->mixer_volume[addr][1] != right;
 776         dummy->mixer_volume[addr][0] = left;
 777         dummy->mixer_volume[addr][1] = right;
 778         spin_unlock_irq(&dummy->mixer_lock);
 779         return change;
 780 }
 781
 782 static const DECLARE_TLV_DB_SCALE(db_scale_dummy, -4500, 30, 0);
 783
 784 #define DUMMY_CAPSRC(xname, xindex, addr) \
 785 { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
 786   .info = snd_dummy_capsrc_info, \
 787   .get = snd_dummy_capsrc_get, .put = snd_dummy_capsrc_put, \
 788   .private_value = addr }
 789
 790 #define snd_dummy_capsrc_info   snd_ctl_boolean_stereo_info
 791
 792 static int snd_dummy_capsrc_get(struct snd_kcontrol *kcontrol,
 793                                 struct snd_ctl_elem_value *ucontrol)
 794 {
 795         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 796         int addr = kcontrol->private_value;
 797
 798         spin_lock_irq(&dummy->mixer_lock);
 799         ucontrol->value.integer.value[0] = dummy->capture_source[addr][0];
 800         ucontrol->value.integer.value[1] = dummy->capture_source[addr][1];
 801         spin_unlock_irq(&dummy->mixer_lock);
 802         return 0;
 803 }
 804
 805 static int snd_dummy_capsrc_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
 806 {
 807         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 808         int change, addr = kcontrol->private_value;
 809         int left, right;
 810
 811         left = ucontrol->value.integer.value[0] & 1;
 812         right = ucontrol->value.integer.value[1] & 1;
 813         spin_lock_irq(&dummy->mixer_lock);
 814         change = dummy->capture_source[addr][0] != left &&
 815                  dummy->capture_source[addr][1] != right;
 816         dummy->capture_source[addr][0] = left;
 817         dummy->capture_source[addr][1] = right;
 818         spin_unlock_irq(&dummy->mixer_lock);
 819         return change;
 820 }
 821
 822 static int snd_dummy_iobox_info(struct snd_kcontrol *kcontrol,
 823                                 struct snd_ctl_elem_info *info)
 824 {
 825         const char *const names[] = { "None", "CD Player" };
 826
 827         return snd_ctl_enum_info(info, 1, 2, names);
 828 }
 829
 830 static int snd_dummy_iobox_get(struct snd_kcontrol *kcontrol,
 831                                struct snd_ctl_elem_value *value)
 832 {
 833         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 834
 835         value->value.enumerated.item[0] = dummy->iobox;
 836         return 0;
 837 }
 838
 839 static int snd_dummy_iobox_put(struct snd_kcontrol *kcontrol,
 840                                struct snd_ctl_elem_value *value)
 841 {
 842         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 843         int changed;
 844
 845         if (value->value.enumerated.item[0] > 1)
 846                 return -EINVAL;
 847
 848         changed = value->value.enumerated.item[0] != dummy->iobox;
 849         if (changed) {
 850                 dummy->iobox = value->value.enumerated.item[0];
 851
 852                 if (dummy->iobox) {
 853                         dummy->cd_volume_ctl->vd[0].access &=
 854                                 ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 855                         dummy->cd_switch_ctl->vd[0].access &=
 856                                 ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 857                 } else {
 858                         dummy->cd_volume_ctl->vd[0].access |=
 859                                 SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 860                         dummy->cd_switch_ctl->vd[0].access |=
 861                                 SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 862                 }
 863
 864                 snd_ctl_notify(dummy->card, SNDRV_CTL_EVENT_MASK_INFO,
 865                                &dummy->cd_volume_ctl->id);
 866                 snd_ctl_notify(dummy->card, SNDRV_CTL_EVENT_MASK_INFO,
 867                                &dummy->cd_switch_ctl->id);
 868         }
 869
 870         return changed;
 871 }
 872
 873 static struct snd_kcontrol_new snd_dummy_controls[] = {
 874 DUMMY_VOLUME("Master Volume", 0, MIXER_ADDR_MASTER),
 875 DUMMY_CAPSRC("Master Capture Switch", 0, MIXER_ADDR_MASTER),
 876 DUMMY_VOLUME("Synth Volume", 0, MIXER_ADDR_SYNTH),
 877 DUMMY_CAPSRC("Synth Capture Switch", 0, MIXER_ADDR_SYNTH),
 878 DUMMY_VOLUME("Line Volume", 0, MIXER_ADDR_LINE),
 879 DUMMY_CAPSRC("Line Capture Switch", 0, MIXER_ADDR_LINE),
 880 DUMMY_VOLUME("Mic Volume", 0, MIXER_ADDR_MIC),
 881 DUMMY_CAPSRC("Mic Capture Switch", 0, MIXER_ADDR_MIC),
 882 DUMMY_VOLUME("CD Volume", 0, MIXER_ADDR_CD),
 883 DUMMY_CAPSRC("CD Capture Switch", 0, MIXER_ADDR_CD),
 884 {
 885         .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 886         .name  = "External I/O Box",
 887         .info  = snd_dummy_iobox_info,
 888         .get   = snd_dummy_iobox_get,
 889         .put   = snd_dummy_iobox_put,
 890 },
 891 };
 892
 893 static int snd_card_dummy_new_mixer(struct snd_dummy *dummy)
 894 {
 895         struct snd_card *card = dummy->card;
 896         struct snd_kcontrol *kcontrol;
 897         unsigned int idx;
 898         int err;
 899
 900         spin_lock_init(&dummy->mixer_lock);
 901         strcpy(card->mixername, "Dummy Mixer");
 902         dummy->iobox = 1;
 903
 904         for (idx = 0; idx < ARRAY_SIZE(snd_dummy_controls); idx++) {
 905                 kcontrol = snd_ctl_new1(&snd_dummy_controls[idx], dummy);
 906                 err = snd_ctl_add(card, kcontrol);
 907                 if (err < 0)
 908                         return err;
 909                 if (!strcmp(kcontrol->id.name, "CD Volume"))
 910                         dummy->cd_volume_ctl = kcontrol;
 911                 else if (!strcmp(kcontrol->id.name, "CD Capture Switch"))
 912                         dummy->cd_switch_ctl = kcontrol;
 913
 914         }
 915         return 0;
 916 }
 917
 918 #if defined(CONFIG_SND_DEBUG) && defined(CONFIG_SND_PROC_FS)
 919 /*
 920  * proc interface
 921  */
 922 static void print_formats(struct snd_dummy *dummy,
 923                           struct snd_info_buffer *buffer)
 924 {
 925         int i;
 926
 927         for (i = 0; i < SNDRV_PCM_FORMAT_LAST; i++) {
 928                 if (dummy->pcm_hw.formats & (1ULL << i))
 929                         snd_iprintf(buffer, " %s", snd_pcm_format_name(i));
 930         }
 931 }
 932
 933 static void print_rates(struct snd_dummy *dummy,
 934                         struct snd_info_buffer *buffer)
 935 {
 936         static int rates[] = {
 937                 5512, 8000, 11025, 16000, 22050, 32000, 44100, 48000,
 938                 64000, 88200, 96000, 176400, 192000,
 939         };
 940         int i;
 941
 942         if (dummy->pcm_hw.rates & SNDRV_PCM_RATE_CONTINUOUS)
 943                 snd_iprintf(buffer, " continuous");
 944         if (dummy->pcm_hw.rates & SNDRV_PCM_RATE_KNOT)
 945                 snd_iprintf(buffer, " knot");
 946         for (i = 0; i < ARRAY_SIZE(rates); i++)
 947                 if (dummy->pcm_hw.rates & (1 << i))
 948                         snd_iprintf(buffer, " %d", rates[i]);
 949 }
 950
 951 #define get_dummy_int_ptr(dummy, ofs) \
 952         (unsigned int *)((char *)&((dummy)->pcm_hw) + (ofs))
 953 #define get_dummy_ll_ptr(dummy, ofs) \
 954         (unsigned long long *)((char *)&((dummy)->pcm_hw) + (ofs))
 955
 956 struct dummy_hw_field {
 957         const char *name;
 958         const char *format;
 959         unsigned int offset;
 960         unsigned int size;
 961 };
 962 #define FIELD_ENTRY(item, fmt) {                   \
 963         .name = #item,                             \
 964         .format = fmt,                             \
 965         .offset = offsetof(struct snd_pcm_hardware, item), \
 966         .size = sizeof(dummy_pcm_hardware.item) }
 967
 968 static struct dummy_hw_field fields[] = {
 969         FIELD_ENTRY(formats, "%#llx"),
 970         FIELD_ENTRY(rates, "%#x"),
 971         FIELD_ENTRY(rate_min, "%d"),
 972         FIELD_ENTRY(rate_max, "%d"),
 973         FIELD_ENTRY(channels_min, "%d"),
 974         FIELD_ENTRY(channels_max, "%d"),
 975         FIELD_ENTRY(buffer_bytes_max, "%ld"),
 976         FIELD_ENTRY(period_bytes_min, "%ld"),
 977         FIELD_ENTRY(period_bytes_max, "%ld"),
 978         FIELD_ENTRY(periods_min, "%d"),
 979         FIELD_ENTRY(periods_max, "%d"),
 980 };
 981
 982 static void dummy_proc_read(struct snd_info_entry *entry,
 983                             struct snd_info_buffer *buffer)
 984 {
 985         struct snd_dummy *dummy = entry->private_data;
 986         int i;
 987
 988         for (i = 0; i < ARRAY_SIZE(fields); i++) {
 989                 snd_iprintf(buffer, "%s ", fields[i].name);
 990                 if (fields[i].size == sizeof(int))
 991                         snd_iprintf(buffer, fields[i].format,
 992                                 *get_dummy_int_ptr(dummy, fields[i].offset));
 993                 else
 994                         snd_iprintf(buffer, fields[i].format,
 995                                 *get_dummy_ll_ptr(dummy, fields[i].offset));
 996                 if (!strcmp(fields[i].name, "formats"))
 997                         print_formats(dummy, buffer);
 998                 else if (!strcmp(fields[i].name, "rates"))
 999                         print_rates(dummy, buffer);
1000                 snd_iprintf(buffer, "\n");
1001         }
1002 }
1003
1004 static void dummy_proc_write(struct snd_info_entry *entry,
1005                              struct snd_info_buffer *buffer)
1006 {
1007         struct snd_dummy *dummy = entry->private_data;
1008         char line[64];
1009
1010         while (!snd_info_get_line(buffer, line, sizeof(line))) {
1011                 char item[20];
1012                 const char *ptr;
1013                 unsigned long long val;
1014                 int i;
1015
1016                 ptr = snd_info_get_str(item, line, sizeof(item));
1017                 for (i = 0; i < ARRAY_SIZE(fields); i++) {
1018                         if (!strcmp(item, fields[i].name))
1019                                 break;
1020                 }
1021                 if (i >= ARRAY_SIZE(fields))
1022                         continue;
1023                 snd_info_get_str(item, ptr, sizeof(item));
1024                 if (kstrtoull(item, 0, &val))
1025                         continue;
1026                 if (fields[i].size == sizeof(int))
1027                         *get_dummy_int_ptr(dummy, fields[i].offset) = val;
1028                 else
1029                         *get_dummy_ll_ptr(dummy, fields[i].offset) = val;
1030         }
1031 }
1032
1033 static void dummy_proc_init(struct snd_dummy *chip)
1034 {
1035         struct snd_info_entry *entry;
1036
1037         if (!snd_card_proc_new(chip->card, "dummy_pcm", &entry)) {
1038                 snd_info_set_text_ops(entry, chip, dummy_proc_read);
1039                 entry->c.text.write = dummy_proc_write;
1040                 entry->mode |= S_IWUSR;
1041                 entry->private_data = chip;
1042         }
1043 }
1044 #else
1045 #define dummy_proc_init(x)
1046 #endif /* CONFIG_SND_DEBUG && CONFIG_SND_PROC_FS */
1047
1048 static int snd_dummy_probe(struct platform_device *devptr)
1049 {
1050         struct snd_card *card;
1051         struct snd_dummy *dummy;
1052         struct dummy_model *m = NULL, **mdl;
1053         int idx, err;
1054         int dev = devptr->id;
1055
1056         err = snd_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
1057                            sizeof(struct snd_dummy), &card);
1058         if (err < 0)
1059                 return err;
1060         dummy = card->private_data;
1061         dummy->card = card;
1062         for (mdl = dummy_models; *mdl && model[dev]; mdl++) {
1063                 if (strcmp(model[dev], (*mdl)->name) == 0) {
1064                         printk(KERN_INFO
1065                                 "snd-dummy: Using model '%s' for card %i\n",
1066                                 (*mdl)->name, card->number);
1067                         m = dummy->model = *mdl;
1068                         break;
1069                 }
1070         }
1071         for (idx = 0; idx < MAX_PCM_DEVICES && idx < pcm_devs[dev]; idx++) {
1072                 if (pcm_substreams[dev] < 1)
1073                         pcm_substreams[dev] = 1;
1074                 if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
1075                         pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
1076                 err = snd_card_dummy_pcm(dummy, idx, pcm_substreams[dev]);
1077                 if (err < 0)
1078                         goto __nodev;
1079         }
1080
1081         dummy->pcm_hw = dummy_pcm_hardware;
1082         if (m) {
1083                 if (m->formats)
1084                         dummy->pcm_hw.formats = m->formats;
1085                 if (m->buffer_bytes_max)
1086                         dummy->pcm_hw.buffer_bytes_max = m->buffer_bytes_max;
1087                 if (m->period_bytes_min)
1088                         dummy->pcm_hw.period_bytes_min = m->period_bytes_min;
1089                 if (m->period_bytes_max)
1090                         dummy->pcm_hw.period_bytes_max = m->period_bytes_max;
1091                 if (m->periods_min)
1092                         dummy->pcm_hw.periods_min = m->periods_min;
1093                 if (m->periods_max)
1094                         dummy->pcm_hw.periods_max = m->periods_max;
1095                 if (m->rates)
1096                         dummy->pcm_hw.rates = m->rates;
1097                 if (m->rate_min)
1098                         dummy->pcm_hw.rate_min = m->rate_min;
1099                 if (m->rate_max)
1100                         dummy->pcm_hw.rate_max = m->rate_max;
1101                 if (m->channels_min)
1102                         dummy->pcm_hw.channels_min = m->channels_min;
1103                 if (m->channels_max)
1104                         dummy->pcm_hw.channels_max = m->channels_max;
1105         }
1106
1107         err = snd_card_dummy_new_mixer(dummy);
1108         if (err < 0)
1109                 goto __nodev;
1110         strcpy(card->driver, "Dummy");
1111         strcpy(card->shortname, "Dummy");
1112         sprintf(card->longname, "Dummy %i", dev + 1);
1113
1114         dummy_proc_init(dummy);
1115
1116         err = snd_card_register(card);
1117         if (err == 0) {
1118                 platform_set_drvdata(devptr, card);
1119                 return 0;
1120         }
1121       __nodev:
1122         snd_card_free(card);
1123         return err;
1124 }
1125
1126 static int snd_dummy_remove(struct platform_device *devptr)
1127 {
1128         snd_card_free(platform_get_drvdata(devptr));
1129         return 0;
1130 }
1131
1132 #ifdef CONFIG_PM_SLEEP
1133 static int snd_dummy_suspend(struct device *pdev)
1134 {
1135         struct snd_card *card = dev_get_drvdata(pdev);
1136         struct snd_dummy *dummy = card->private_data;
1137
1138         snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
1139         snd_pcm_suspend_all(dummy->pcm);
1140         return 0;
1141 }
1142
1143 static int snd_dummy_resume(struct device *pdev)
1144 {
1145         struct snd_card *card = dev_get_drvdata(pdev);
1146
1147         snd_power_change_state(card, SNDRV_CTL_POWER_D0);
1148         return 0;
1149 }
1150
1151 static SIMPLE_DEV_PM_OPS(snd_dummy_pm, snd_dummy_suspend, snd_dummy_resume);
1152 #define SND_DUMMY_PM_OPS        &snd_dummy_pm
1153 #else
1154 #define SND_DUMMY_PM_OPS        NULL
1155 #endif
1156
1157 #define SND_DUMMY_DRIVER        "snd_dummy"
1158
1159 static struct platform_driver snd_dummy_driver = {
1160         .probe          = snd_dummy_probe,
1161         .remove         = snd_dummy_remove,
1162         .driver         = {
1163                 .name   = SND_DUMMY_DRIVER,
1164                 .pm     = SND_DUMMY_PM_OPS,
1165         },
1166 };
1167
1168 static void snd_dummy_unregister_all(void)
1169 {
1170         int i;
1171
1172         for (i = 0; i < ARRAY_SIZE(devices); ++i)
1173                 platform_device_unregister(devices[i]);
1174         platform_driver_unregister(&snd_dummy_driver);
1175         free_fake_buffer();
1176 }
1177
1178 static int __init alsa_card_dummy_init(void)
1179 {
1180         int i, cards, err;
1181
1182         err = platform_driver_register(&snd_dummy_driver);
1183         if (err < 0)
1184                 return err;
1185
1186         err = alloc_fake_buffer();
1187         if (err < 0) {
1188                 platform_driver_unregister(&snd_dummy_driver);
1189                 return err;
1190         }
1191
1192         cards = 0;
1193         for (i = 0; i < SNDRV_CARDS; i++) {
1194                 struct platform_device *device;
1195                 if (! enable[i])
1196                         continue;
1197                 device = platform_device_register_simple(SND_DUMMY_DRIVER,
1198                                                          i, NULL, 0);
1199                 if (IS_ERR(device))
1200                         continue;
1201                 if (!platform_get_drvdata(device)) {
1202                         platform_device_unregister(device);
1203                         continue;
1204                 }
1205                 devices[i] = device;
1206                 cards++;
1207         }
1208         if (!cards) {
1209 #ifdef MODULE
1210                 printk(KERN_ERR "Dummy soundcard not found or device busy\n");
1211 #endif
1212                 snd_dummy_unregister_all();
1213                 return -ENODEV;
1214         }
1215         return 0;
1216 }
1217
1218 static void __exit alsa_card_dummy_exit(void)
1219 {
1220         snd_dummy_unregister_all();
1221 }
1222
1223 module_init(alsa_card_dummy_init)
1224 module_exit(alsa_card_dummy_exit)