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/moduleparam.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/initval.h>
  37
  38 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
  39 MODULE_DESCRIPTION("Dummy soundcard (/dev/null)");
  40 MODULE_LICENSE("GPL");
  41 MODULE_SUPPORTED_DEVICE("{{ALSA,Dummy soundcard}}");
  42
  43 #define MAX_PCM_DEVICES         4
  44 #define MAX_PCM_SUBSTREAMS      16
  45 #define MAX_MIDI_DEVICES        2
  46
  47 #if 0 /* emu10k1 emulation */
  48 #define MAX_BUFFER_SIZE         (128 * 1024)
  49 static int emu10k1_playback_constraints(struct snd_pcm_runtime *runtime)
  50 {
  51         int err;
  52         err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
  53         if (err < 0)
  54                 return err;
  55         err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX);
  56         if (err < 0)
  57                 return err;
  58         return 0;
  59 }
  60 #define add_playback_constraints emu10k1_playback_constraints
  61 #endif
  62
  63 #if 0 /* RME9652 emulation */
  64 #define MAX_BUFFER_SIZE         (26 * 64 * 1024)
  65 #define USE_FORMATS             SNDRV_PCM_FMTBIT_S32_LE
  66 #define USE_CHANNELS_MIN        26
  67 #define USE_CHANNELS_MAX        26
  68 #define USE_PERIODS_MIN         2
  69 #define USE_PERIODS_MAX         2
  70 #endif
  71
  72 #if 0 /* ICE1712 emulation */
  73 #define MAX_BUFFER_SIZE         (256 * 1024)
  74 #define USE_FORMATS             SNDRV_PCM_FMTBIT_S32_LE
  75 #define USE_CHANNELS_MIN        10
  76 #define USE_CHANNELS_MAX        10
  77 #define USE_PERIODS_MIN         1
  78 #define USE_PERIODS_MAX         1024
  79 #endif
  80
  81 #if 0 /* UDA1341 emulation */
  82 #define MAX_BUFFER_SIZE         (16380)
  83 #define USE_FORMATS             SNDRV_PCM_FMTBIT_S16_LE
  84 #define USE_CHANNELS_MIN        2
  85 #define USE_CHANNELS_MAX        2
  86 #define USE_PERIODS_MIN         2
  87 #define USE_PERIODS_MAX         255
  88 #endif
  89
  90 #if 0 /* simple AC97 bridge (intel8x0) with 48kHz AC97 only codec */
  91 #define USE_FORMATS             SNDRV_PCM_FMTBIT_S16_LE
  92 #define USE_CHANNELS_MIN        2
  93 #define USE_CHANNELS_MAX        2
  94 #define USE_RATE                SNDRV_PCM_RATE_48000
  95 #define USE_RATE_MIN            48000
  96 #define USE_RATE_MAX            48000
  97 #endif
  98
  99 #if 0 /* CA0106 */
 100 #define USE_FORMATS             SNDRV_PCM_FMTBIT_S16_LE
 101 #define USE_CHANNELS_MIN        2
 102 #define USE_CHANNELS_MAX        2
 103 #define USE_RATE                (SNDRV_PCM_RATE_48000|SNDRV_PCM_RATE_96000|SNDRV_PCM_RATE_192000)
 104 #define USE_RATE_MIN            48000
 105 #define USE_RATE_MAX            192000
 106 #define MAX_BUFFER_SIZE         ((65536-64)*8)
 107 #define MAX_PERIOD_SIZE         (65536-64)
 108 #define USE_PERIODS_MIN         2
 109 #define USE_PERIODS_MAX         8
 110 #endif
 111
 112
 113 /* defaults */
 114 #ifndef MAX_BUFFER_SIZE
 115 #define MAX_BUFFER_SIZE         (64*1024)
 116 #endif
 117 #ifndef MAX_PERIOD_SIZE
 118 #define MAX_PERIOD_SIZE         MAX_BUFFER_SIZE
 119 #endif
 120 #ifndef USE_FORMATS
 121 #define USE_FORMATS             (SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE)
 122 #endif
 123 #ifndef USE_RATE
 124 #define USE_RATE                SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000
 125 #define USE_RATE_MIN            5500
 126 #define USE_RATE_MAX            48000
 127 #endif
 128 #ifndef USE_CHANNELS_MIN
 129 #define USE_CHANNELS_MIN        1
 130 #endif
 131 #ifndef USE_CHANNELS_MAX
 132 #define USE_CHANNELS_MAX        2
 133 #endif
 134 #ifndef USE_PERIODS_MIN
 135 #define USE_PERIODS_MIN         1
 136 #endif
 137 #ifndef USE_PERIODS_MAX
 138 #define USE_PERIODS_MAX         1024
 139 #endif
 140 #ifndef add_playback_constraints
 141 #define add_playback_constraints(x) 0
 142 #endif
 143 #ifndef add_capture_constraints
 144 #define add_capture_constraints(x) 0
 145 #endif
 146
 147 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;      /* Index 0-MAX */
 148 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;       /* ID for this card */
 149 static int enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
 150 static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
 151 static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8};
 152 //static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2};
 153 #ifdef CONFIG_HIGH_RES_TIMERS
 154 static int hrtimer = 1;
 155 #endif
 156
 157 module_param_array(index, int, NULL, 0444);
 158 MODULE_PARM_DESC(index, "Index value for dummy soundcard.");
 159 module_param_array(id, charp, NULL, 0444);
 160 MODULE_PARM_DESC(id, "ID string for dummy soundcard.");
 161 module_param_array(enable, bool, NULL, 0444);
 162 MODULE_PARM_DESC(enable, "Enable this dummy soundcard.");
 163 module_param_array(pcm_devs, int, NULL, 0444);
 164 MODULE_PARM_DESC(pcm_devs, "PCM devices # (0-4) for dummy driver.");
 165 module_param_array(pcm_substreams, int, NULL, 0444);
 166 MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-16) for dummy driver.");
 167 //module_param_array(midi_devs, int, NULL, 0444);
 168 //MODULE_PARM_DESC(midi_devs, "MIDI devices # (0-2) for dummy driver.");
 169 #ifdef CONFIG_HIGH_RES_TIMERS
 170 module_param(hrtimer, bool, 0644);
 171 MODULE_PARM_DESC(hrtimer, "Use hrtimer as the timer source.");
 172 #endif
 173
 174 static struct platform_device *devices[SNDRV_CARDS];
 175
 176 #define MIXER_ADDR_MASTER       0
 177 #define MIXER_ADDR_LINE         1
 178 #define MIXER_ADDR_MIC          2
 179 #define MIXER_ADDR_SYNTH        3
 180 #define MIXER_ADDR_CD           4
 181 #define MIXER_ADDR_LAST         4
 182
 183 struct dummy_timer_ops {
 184         int (*create)(struct snd_pcm_substream *);
 185         void (*free)(struct snd_pcm_substream *);
 186         int (*prepare)(struct snd_pcm_substream *);
 187         int (*start)(struct snd_pcm_substream *);
 188         int (*stop)(struct snd_pcm_substream *);
 189         snd_pcm_uframes_t (*pointer)(struct snd_pcm_substream *);
 190 };
 191
 192 struct snd_dummy {
 193         struct snd_card *card;
 194         struct snd_pcm *pcm;
 195         spinlock_t mixer_lock;
 196         int mixer_volume[MIXER_ADDR_LAST+1][2];
 197         int capture_source[MIXER_ADDR_LAST+1][2];
 198         const struct dummy_timer_ops *timer_ops;
 199 };
 200
 201 /*
 202  * system timer interface
 203  */
 204
 205 struct dummy_systimer_pcm {
 206         spinlock_t lock;
 207         struct timer_list timer;
 208         unsigned int pcm_buffer_size;
 209         unsigned int pcm_period_size;
 210         unsigned int pcm_bps;           /* bytes per second */
 211         unsigned int pcm_hz;            /* HZ */
 212         unsigned int pcm_irq_pos;       /* IRQ position */
 213         unsigned int pcm_buf_pos;       /* position in buffer */
 214         struct snd_pcm_substream *substream;
 215 };
 216
 217 static int dummy_systimer_start(struct snd_pcm_substream *substream)
 218 {
 219         struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 220         spin_lock(&dpcm->lock);
 221         dpcm->timer.expires = 1 + jiffies;
 222         add_timer(&dpcm->timer);
 223         spin_unlock(&dpcm->lock);
 224         return 0;
 225 }
 226
 227 static int dummy_systimer_stop(struct snd_pcm_substream *substream)
 228 {
 229         struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 230         spin_lock(&dpcm->lock);
 231         del_timer(&dpcm->timer);
 232         spin_unlock(&dpcm->lock);
 233         return 0;
 234 }
 235
 236 static int dummy_systimer_prepare(struct snd_pcm_substream *substream)
 237 {
 238         struct snd_pcm_runtime *runtime = substream->runtime;
 239         struct dummy_systimer_pcm *dpcm = runtime->private_data;
 240         int bps;
 241
 242         bps = snd_pcm_format_width(runtime->format) * runtime->rate *
 243                 runtime->channels / 8;
 244
 245         if (bps <= 0)
 246                 return -EINVAL;
 247
 248         dpcm->pcm_bps = bps;
 249         dpcm->pcm_hz = HZ;
 250         dpcm->pcm_buffer_size = snd_pcm_lib_buffer_bytes(substream);
 251         dpcm->pcm_period_size = snd_pcm_lib_period_bytes(substream);
 252         dpcm->pcm_irq_pos = 0;
 253         dpcm->pcm_buf_pos = 0;
 254
 255         return 0;
 256 }
 257
 258 static void dummy_systimer_callback(unsigned long data)
 259 {
 260         struct dummy_systimer_pcm *dpcm = (struct dummy_systimer_pcm *)data;
 261         unsigned long flags;
 262
 263         spin_lock_irqsave(&dpcm->lock, flags);
 264         dpcm->timer.expires = 1 + jiffies;
 265         add_timer(&dpcm->timer);
 266         dpcm->pcm_irq_pos += dpcm->pcm_bps;
 267         dpcm->pcm_buf_pos += dpcm->pcm_bps;
 268         dpcm->pcm_buf_pos %= dpcm->pcm_buffer_size * dpcm->pcm_hz;
 269         if (dpcm->pcm_irq_pos >= dpcm->pcm_period_size * dpcm->pcm_hz) {
 270                 dpcm->pcm_irq_pos %= dpcm->pcm_period_size * dpcm->pcm_hz;
 271                 spin_unlock_irqrestore(&dpcm->lock, flags);
 272                 snd_pcm_period_elapsed(dpcm->substream);
 273         } else
 274                 spin_unlock_irqrestore(&dpcm->lock, flags);
 275 }
 276
 277 static snd_pcm_uframes_t
 278 dummy_systimer_pointer(struct snd_pcm_substream *substream)
 279 {
 280         struct snd_pcm_runtime *runtime = substream->runtime;
 281         struct dummy_systimer_pcm *dpcm = runtime->private_data;
 282
 283         return bytes_to_frames(runtime, dpcm->pcm_buf_pos / dpcm->pcm_hz);
 284 }
 285
 286 static int dummy_systimer_create(struct snd_pcm_substream *substream)
 287 {
 288         struct dummy_systimer_pcm *dpcm;
 289
 290         dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 291         if (!dpcm)
 292                 return -ENOMEM;
 293         substream->runtime->private_data = dpcm;
 294         init_timer(&dpcm->timer);
 295         dpcm->timer.data = (unsigned long) dpcm;
 296         dpcm->timer.function = dummy_systimer_callback;
 297         spin_lock_init(&dpcm->lock);
 298         dpcm->substream = substream;
 299         return 0;
 300 }
 301
 302 static void dummy_systimer_free(struct snd_pcm_substream *substream)
 303 {
 304         kfree(substream->runtime->private_data);
 305 }
 306
 307 static struct dummy_timer_ops dummy_systimer_ops = {
 308         .create =       dummy_systimer_create,
 309         .free =         dummy_systimer_free,
 310         .prepare =      dummy_systimer_prepare,
 311         .start =        dummy_systimer_start,
 312         .stop =         dummy_systimer_stop,
 313         .pointer =      dummy_systimer_pointer,
 314 };
 315
 316 #ifdef CONFIG_HIGH_RES_TIMERS
 317 /*
 318  * hrtimer interface
 319  */
 320
 321 struct dummy_hrtimer_pcm {
 322         ktime_t base_time;
 323         ktime_t period_time;
 324         atomic_t running;
 325         struct hrtimer timer;
 326         struct tasklet_struct tasklet;
 327         struct snd_pcm_substream *substream;
 328 };
 329
 330 static void dummy_hrtimer_pcm_elapsed(unsigned long priv)
 331 {
 332         struct dummy_hrtimer_pcm *dpcm = (struct dummy_hrtimer_pcm *)priv;
 333         if (atomic_read(&dpcm->running))
 334                 snd_pcm_period_elapsed(dpcm->substream);
 335 }
 336
 337 static enum hrtimer_restart dummy_hrtimer_callback(struct hrtimer *timer)
 338 {
 339         struct dummy_hrtimer_pcm *dpcm;
 340
 341         dpcm = container_of(timer, struct dummy_hrtimer_pcm, timer);
 342         if (!atomic_read(&dpcm->running))
 343                 return HRTIMER_NORESTART;
 344         tasklet_schedule(&dpcm->tasklet);
 345         hrtimer_forward_now(timer, dpcm->period_time);
 346         return HRTIMER_RESTART;
 347 }
 348
 349 static int dummy_hrtimer_start(struct snd_pcm_substream *substream)
 350 {
 351         struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 352
 353         dpcm->base_time = hrtimer_cb_get_time(&dpcm->timer);
 354         hrtimer_start(&dpcm->timer, dpcm->period_time, HRTIMER_MODE_REL);
 355         atomic_set(&dpcm->running, 1);
 356         return 0;
 357 }
 358
 359 static int dummy_hrtimer_stop(struct snd_pcm_substream *substream)
 360 {
 361         struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 362
 363         atomic_set(&dpcm->running, 0);
 364         hrtimer_cancel(&dpcm->timer);
 365         return 0;
 366 }
 367
 368 static inline void dummy_hrtimer_sync(struct dummy_hrtimer_pcm *dpcm)
 369 {
 370         tasklet_kill(&dpcm->tasklet);
 371 }
 372
 373 static snd_pcm_uframes_t
 374 dummy_hrtimer_pointer(struct snd_pcm_substream *substream)
 375 {
 376         struct snd_pcm_runtime *runtime = substream->runtime;
 377         struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 378         u64 delta;
 379         u32 pos;
 380
 381         delta = ktime_us_delta(hrtimer_cb_get_time(&dpcm->timer),
 382                                dpcm->base_time);
 383         delta = div_u64(delta * runtime->rate + 999999, 1000000);
 384         div_u64_rem(delta, runtime->buffer_size, &pos);
 385         return pos;
 386 }
 387
 388 static int dummy_hrtimer_prepare(struct snd_pcm_substream *substream)
 389 {
 390         struct snd_pcm_runtime *runtime = substream->runtime;
 391         struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 392         unsigned int period, rate;
 393         long sec;
 394         unsigned long nsecs;
 395
 396         dummy_hrtimer_sync(dpcm);
 397         period = runtime->period_size;
 398         rate = runtime->rate;
 399         sec = period / rate;
 400         period %= rate;
 401         nsecs = div_u64((u64)period * 1000000000UL + rate - 1, rate);
 402         dpcm->period_time = ktime_set(sec, nsecs);
 403
 404         return 0;
 405 }
 406
 407 static int dummy_hrtimer_create(struct snd_pcm_substream *substream)
 408 {
 409         struct dummy_hrtimer_pcm *dpcm;
 410
 411         dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 412         if (!dpcm)
 413                 return -ENOMEM;
 414         substream->runtime->private_data = dpcm;
 415         hrtimer_init(&dpcm->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 416         dpcm->timer.function = dummy_hrtimer_callback;
 417         dpcm->substream = substream;
 418         atomic_set(&dpcm->running, 0);
 419         tasklet_init(&dpcm->tasklet, dummy_hrtimer_pcm_elapsed,
 420                      (unsigned long)dpcm);
 421         return 0;
 422 }
 423
 424 static void dummy_hrtimer_free(struct snd_pcm_substream *substream)
 425 {
 426         struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 427         dummy_hrtimer_sync(dpcm);
 428         kfree(dpcm);
 429 }
 430
 431 static struct dummy_timer_ops dummy_hrtimer_ops = {
 432         .create =       dummy_hrtimer_create,
 433         .free =         dummy_hrtimer_free,
 434         .prepare =      dummy_hrtimer_prepare,
 435         .start =        dummy_hrtimer_start,
 436         .stop =         dummy_hrtimer_stop,
 437         .pointer =      dummy_hrtimer_pointer,
 438 };
 439
 440 #endif /* CONFIG_HIGH_RES_TIMERS */
 441
 442 /*
 443  * PCM interface
 444  */
 445
 446 static int dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 447 {
 448         struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 449
 450         switch (cmd) {
 451         case SNDRV_PCM_TRIGGER_START:
 452         case SNDRV_PCM_TRIGGER_RESUME:
 453                 return dummy->timer_ops->start(substream);
 454         case SNDRV_PCM_TRIGGER_STOP:
 455         case SNDRV_PCM_TRIGGER_SUSPEND:
 456                 return dummy->timer_ops->stop(substream);
 457         }
 458         return -EINVAL;
 459 }
 460
 461 static int dummy_pcm_prepare(struct snd_pcm_substream *substream)
 462 {
 463         struct snd_pcm_runtime *runtime = substream->runtime;
 464         struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 465
 466         snd_pcm_format_set_silence(runtime->format, runtime->dma_area,
 467                         bytes_to_samples(runtime, runtime->dma_bytes));
 468         return dummy->timer_ops->prepare(substream);
 469 }
 470
 471 static snd_pcm_uframes_t dummy_pcm_pointer(struct snd_pcm_substream *substream)
 472 {
 473         struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 474
 475         return dummy->timer_ops->pointer(substream);
 476 }
 477
 478 static struct snd_pcm_hardware dummy_pcm_hardware = {
 479         .info =                 (SNDRV_PCM_INFO_MMAP |
 480                                  SNDRV_PCM_INFO_INTERLEAVED |
 481                                  SNDRV_PCM_INFO_RESUME |
 482                                  SNDRV_PCM_INFO_MMAP_VALID),
 483         .formats =              USE_FORMATS,
 484         .rates =                USE_RATE,
 485         .rate_min =             USE_RATE_MIN,
 486         .rate_max =             USE_RATE_MAX,
 487         .channels_min =         USE_CHANNELS_MIN,
 488         .channels_max =         USE_CHANNELS_MAX,
 489         .buffer_bytes_max =     MAX_BUFFER_SIZE,
 490         .period_bytes_min =     64,
 491         .period_bytes_max =     MAX_PERIOD_SIZE,
 492         .periods_min =          USE_PERIODS_MIN,
 493         .periods_max =          USE_PERIODS_MAX,
 494         .fifo_size =            0,
 495 };
 496
 497 static int dummy_pcm_hw_params(struct snd_pcm_substream *substream,
 498                                struct snd_pcm_hw_params *hw_params)
 499 {
 500         return snd_pcm_lib_malloc_pages(substream,
 501                                         params_buffer_bytes(hw_params));
 502 }
 503
 504 static int dummy_pcm_hw_free(struct snd_pcm_substream *substream)
 505 {
 506         return snd_pcm_lib_free_pages(substream);
 507 }
 508
 509 static int dummy_pcm_open(struct snd_pcm_substream *substream)
 510 {
 511         struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 512         struct snd_pcm_runtime *runtime = substream->runtime;
 513         int err;
 514
 515         dummy->timer_ops = &dummy_systimer_ops;
 516 #ifdef CONFIG_HIGH_RES_TIMERS
 517         if (hrtimer)
 518                 dummy->timer_ops = &dummy_hrtimer_ops;
 519 #endif
 520
 521         err = dummy->timer_ops->create(substream);
 522         if (err < 0)
 523                 return err;
 524
 525         runtime->hw = dummy_pcm_hardware;
 526         if (substream->pcm->device & 1) {
 527                 runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
 528                 runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
 529         }
 530         if (substream->pcm->device & 2)
 531                 runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
 532                                       SNDRV_PCM_INFO_MMAP_VALID);
 533
 534         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 535                 err = add_playback_constraints(substream->runtime);
 536         else
 537                 err = add_capture_constraints(substream->runtime);
 538         if (err < 0) {
 539                 dummy->timer_ops->free(substream);
 540                 return err;
 541         }
 542         return 0;
 543 }
 544
 545 static int dummy_pcm_close(struct snd_pcm_substream *substream)
 546 {
 547         struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 548         dummy->timer_ops->free(substream);
 549         return 0;
 550 }
 551
 552 static struct snd_pcm_ops dummy_pcm_ops = {
 553         .open =         dummy_pcm_open,
 554         .close =        dummy_pcm_close,
 555         .ioctl =        snd_pcm_lib_ioctl,
 556         .hw_params =    dummy_pcm_hw_params,
 557         .hw_free =      dummy_pcm_hw_free,
 558         .prepare =      dummy_pcm_prepare,
 559         .trigger =      dummy_pcm_trigger,
 560         .pointer =      dummy_pcm_pointer,
 561 };
 562
 563 static int __devinit snd_card_dummy_pcm(struct snd_dummy *dummy, int device,
 564                                         int substreams)
 565 {
 566         struct snd_pcm *pcm;
 567         int err;
 568
 569         err = snd_pcm_new(dummy->card, "Dummy PCM", device,
 570                                substreams, substreams, &pcm);
 571         if (err < 0)
 572                 return err;
 573         dummy->pcm = pcm;
 574         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &dummy_pcm_ops);
 575         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &dummy_pcm_ops);
 576         pcm->private_data = dummy;
 577         pcm->info_flags = 0;
 578         strcpy(pcm->name, "Dummy PCM");
 579         snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
 580                                               snd_dma_continuous_data(GFP_KERNEL),
 581                                               0, 64*1024);
 582         return 0;
 583 }
 584
 585 #define DUMMY_VOLUME(xname, xindex, addr) \
 586 { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
 587   .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ, \
 588   .name = xname, .index = xindex, \
 589   .info = snd_dummy_volume_info, \
 590   .get = snd_dummy_volume_get, .put = snd_dummy_volume_put, \
 591   .private_value = addr, \
 592   .tlv = { .p = db_scale_dummy } }
 593
 594 static int snd_dummy_volume_info(struct snd_kcontrol *kcontrol,
 595                                  struct snd_ctl_elem_info *uinfo)
 596 {
 597         uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 598         uinfo->count = 2;
 599         uinfo->value.integer.min = -50;
 600         uinfo->value.integer.max = 100;
 601         return 0;
 602 }
 603
 604 static int snd_dummy_volume_get(struct snd_kcontrol *kcontrol,
 605                                 struct snd_ctl_elem_value *ucontrol)
 606 {
 607         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 608         int addr = kcontrol->private_value;
 609
 610         spin_lock_irq(&dummy->mixer_lock);
 611         ucontrol->value.integer.value[0] = dummy->mixer_volume[addr][0];
 612         ucontrol->value.integer.value[1] = dummy->mixer_volume[addr][1];
 613         spin_unlock_irq(&dummy->mixer_lock);
 614         return 0;
 615 }
 616
 617 static int snd_dummy_volume_put(struct snd_kcontrol *kcontrol,
 618                                 struct snd_ctl_elem_value *ucontrol)
 619 {
 620         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 621         int change, addr = kcontrol->private_value;
 622         int left, right;
 623
 624         left = ucontrol->value.integer.value[0];
 625         if (left < -50)
 626                 left = -50;
 627         if (left > 100)
 628                 left = 100;
 629         right = ucontrol->value.integer.value[1];
 630         if (right < -50)
 631                 right = -50;
 632         if (right > 100)
 633                 right = 100;
 634         spin_lock_irq(&dummy->mixer_lock);
 635         change = dummy->mixer_volume[addr][0] != left ||
 636                  dummy->mixer_volume[addr][1] != right;
 637         dummy->mixer_volume[addr][0] = left;
 638         dummy->mixer_volume[addr][1] = right;
 639         spin_unlock_irq(&dummy->mixer_lock);
 640         return change;
 641 }
 642
 643 static const DECLARE_TLV_DB_SCALE(db_scale_dummy, -4500, 30, 0);
 644
 645 #define DUMMY_CAPSRC(xname, xindex, addr) \
 646 { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
 647   .info = snd_dummy_capsrc_info, \
 648   .get = snd_dummy_capsrc_get, .put = snd_dummy_capsrc_put, \
 649   .private_value = addr }
 650
 651 #define snd_dummy_capsrc_info   snd_ctl_boolean_stereo_info
 652
 653 static int snd_dummy_capsrc_get(struct snd_kcontrol *kcontrol,
 654                                 struct snd_ctl_elem_value *ucontrol)
 655 {
 656         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 657         int addr = kcontrol->private_value;
 658
 659         spin_lock_irq(&dummy->mixer_lock);
 660         ucontrol->value.integer.value[0] = dummy->capture_source[addr][0];
 661         ucontrol->value.integer.value[1] = dummy->capture_source[addr][1];
 662         spin_unlock_irq(&dummy->mixer_lock);
 663         return 0;
 664 }
 665
 666 static int snd_dummy_capsrc_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
 667 {
 668         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 669         int change, addr = kcontrol->private_value;
 670         int left, right;
 671
 672         left = ucontrol->value.integer.value[0] & 1;
 673         right = ucontrol->value.integer.value[1] & 1;
 674         spin_lock_irq(&dummy->mixer_lock);
 675         change = dummy->capture_source[addr][0] != left &&
 676                  dummy->capture_source[addr][1] != right;
 677         dummy->capture_source[addr][0] = left;
 678         dummy->capture_source[addr][1] = right;
 679         spin_unlock_irq(&dummy->mixer_lock);
 680         return change;
 681 }
 682
 683 static struct snd_kcontrol_new snd_dummy_controls[] = {
 684 DUMMY_VOLUME("Master Volume", 0, MIXER_ADDR_MASTER),
 685 DUMMY_CAPSRC("Master Capture Switch", 0, MIXER_ADDR_MASTER),
 686 DUMMY_VOLUME("Synth Volume", 0, MIXER_ADDR_SYNTH),
 687 DUMMY_CAPSRC("Synth Capture Switch", 0, MIXER_ADDR_SYNTH),
 688 DUMMY_VOLUME("Line Volume", 0, MIXER_ADDR_LINE),
 689 DUMMY_CAPSRC("Line Capture Switch", 0, MIXER_ADDR_LINE),
 690 DUMMY_VOLUME("Mic Volume", 0, MIXER_ADDR_MIC),
 691 DUMMY_CAPSRC("Mic Capture Switch", 0, MIXER_ADDR_MIC),
 692 DUMMY_VOLUME("CD Volume", 0, MIXER_ADDR_CD),
 693 DUMMY_CAPSRC("CD Capture Switch", 0, MIXER_ADDR_CD)
 694 };
 695
 696 static int __devinit snd_card_dummy_new_mixer(struct snd_dummy *dummy)
 697 {
 698         struct snd_card *card = dummy->card;
 699         unsigned int idx;
 700         int err;
 701
 702         if (snd_BUG_ON(!dummy))
 703                 return -EINVAL;
 704         spin_lock_init(&dummy->mixer_lock);
 705         strcpy(card->mixername, "Dummy Mixer");
 706
 707         for (idx = 0; idx < ARRAY_SIZE(snd_dummy_controls); idx++) {
 708                 err = snd_ctl_add(card, snd_ctl_new1(&snd_dummy_controls[idx], dummy));
 709                 if (err < 0)
 710                         return err;
 711         }
 712         return 0;
 713 }
 714
 715 static int __devinit snd_dummy_probe(struct platform_device *devptr)
 716 {
 717         struct snd_card *card;
 718         struct snd_dummy *dummy;
 719         int idx, err;
 720         int dev = devptr->id;
 721
 722         err = snd_card_create(index[dev], id[dev], THIS_MODULE,
 723                               sizeof(struct snd_dummy), &card);
 724         if (err < 0)
 725                 return err;
 726         dummy = card->private_data;
 727         dummy->card = card;
 728         for (idx = 0; idx < MAX_PCM_DEVICES && idx < pcm_devs[dev]; idx++) {
 729                 if (pcm_substreams[dev] < 1)
 730                         pcm_substreams[dev] = 1;
 731                 if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
 732                         pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
 733                 err = snd_card_dummy_pcm(dummy, idx, pcm_substreams[dev]);
 734                 if (err < 0)
 735                         goto __nodev;
 736         }
 737         err = snd_card_dummy_new_mixer(dummy);
 738         if (err < 0)
 739                 goto __nodev;
 740         strcpy(card->driver, "Dummy");
 741         strcpy(card->shortname, "Dummy");
 742         sprintf(card->longname, "Dummy %i", dev + 1);
 743
 744         snd_card_set_dev(card, &devptr->dev);
 745
 746         err = snd_card_register(card);
 747         if (err == 0) {
 748                 platform_set_drvdata(devptr, card);
 749                 return 0;
 750         }
 751       __nodev:
 752         snd_card_free(card);
 753         return err;
 754 }
 755
 756 static int __devexit snd_dummy_remove(struct platform_device *devptr)
 757 {
 758         snd_card_free(platform_get_drvdata(devptr));
 759         platform_set_drvdata(devptr, NULL);
 760         return 0;
 761 }
 762
 763 #ifdef CONFIG_PM
 764 static int snd_dummy_suspend(struct platform_device *pdev, pm_message_t state)
 765 {
 766         struct snd_card *card = platform_get_drvdata(pdev);
 767         struct snd_dummy *dummy = card->private_data;
 768
 769         snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
 770         snd_pcm_suspend_all(dummy->pcm);
 771         return 0;
 772 }
 773
 774 static int snd_dummy_resume(struct platform_device *pdev)
 775 {
 776         struct snd_card *card = platform_get_drvdata(pdev);
 777
 778         snd_power_change_state(card, SNDRV_CTL_POWER_D0);
 779         return 0;
 780 }
 781 #endif
 782
 783 #define SND_DUMMY_DRIVER        "snd_dummy"
 784
 785 static struct platform_driver snd_dummy_driver = {
 786         .probe          = snd_dummy_probe,
 787         .remove         = __devexit_p(snd_dummy_remove),
 788 #ifdef CONFIG_PM
 789         .suspend        = snd_dummy_suspend,
 790         .resume         = snd_dummy_resume,
 791 #endif
 792         .driver         = {
 793                 .name   = SND_DUMMY_DRIVER
 794         },
 795 };
 796
 797 static void snd_dummy_unregister_all(void)
 798 {
 799         int i;
 800
 801         for (i = 0; i < ARRAY_SIZE(devices); ++i)
 802                 platform_device_unregister(devices[i]);
 803         platform_driver_unregister(&snd_dummy_driver);
 804 }
 805
 806 static int __init alsa_card_dummy_init(void)
 807 {
 808         int i, cards, err;
 809
 810         err = platform_driver_register(&snd_dummy_driver);
 811         if (err < 0)
 812                 return err;
 813
 814         cards = 0;
 815         for (i = 0; i < SNDRV_CARDS; i++) {
 816                 struct platform_device *device;
 817                 if (! enable[i])
 818                         continue;
 819                 device = platform_device_register_simple(SND_DUMMY_DRIVER,
 820                                                          i, NULL, 0);
 821                 if (IS_ERR(device))
 822                         continue;
 823                 if (!platform_get_drvdata(device)) {
 824                         platform_device_unregister(device);
 825                         continue;
 826                 }
 827                 devices[i] = device;
 828                 cards++;
 829         }
 830         if (!cards) {
 831 #ifdef MODULE
 832                 printk(KERN_ERR "Dummy soundcard not found or device busy\n");
 833 #endif
 834                 snd_dummy_unregister_all();
 835                 return -ENODEV;
 836         }
 837         return 0;
 838 }
 839
 840 static void __exit alsa_card_dummy_exit(void)
 841 {
 842         snd_dummy_unregister_all();
 843 }
 844
 845 module_init(alsa_card_dummy_init)
 846 module_exit(alsa_card_dummy_exit)