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/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 #if 0 /* emu10k1 emulation */
  49 #define MAX_BUFFER_SIZE         (128 * 1024)
  50 static int emu10k1_playback_constraints(struct snd_pcm_runtime *runtime)
  51 {
  52         int err;
  53         err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
  54         if (err < 0)
  55                 return err;
  56         err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX);
  57         if (err < 0)
  58                 return err;
  59         return 0;
  60 }
  61 #define add_playback_constraints emu10k1_playback_constraints
  62 #endif
  63
  64 #if 0 /* RME9652 emulation */
  65 #define MAX_BUFFER_SIZE         (26 * 64 * 1024)
  66 #define USE_FORMATS             SNDRV_PCM_FMTBIT_S32_LE
  67 #define USE_CHANNELS_MIN        26
  68 #define USE_CHANNELS_MAX        26
  69 #define USE_PERIODS_MIN         2
  70 #define USE_PERIODS_MAX         2
  71 #endif
  72
  73 #if 0 /* ICE1712 emulation */
  74 #define MAX_BUFFER_SIZE         (256 * 1024)
  75 #define USE_FORMATS             SNDRV_PCM_FMTBIT_S32_LE
  76 #define USE_CHANNELS_MIN        10
  77 #define USE_CHANNELS_MAX        10
  78 #define USE_PERIODS_MIN         1
  79 #define USE_PERIODS_MAX         1024
  80 #endif
  81
  82 #if 0 /* UDA1341 emulation */
  83 #define MAX_BUFFER_SIZE         (16380)
  84 #define USE_FORMATS             SNDRV_PCM_FMTBIT_S16_LE
  85 #define USE_CHANNELS_MIN        2
  86 #define USE_CHANNELS_MAX        2
  87 #define USE_PERIODS_MIN         2
  88 #define USE_PERIODS_MAX         255
  89 #endif
  90
  91 #if 0 /* simple AC97 bridge (intel8x0) with 48kHz AC97 only codec */
  92 #define USE_FORMATS             SNDRV_PCM_FMTBIT_S16_LE
  93 #define USE_CHANNELS_MIN        2
  94 #define USE_CHANNELS_MAX        2
  95 #define USE_RATE                SNDRV_PCM_RATE_48000
  96 #define USE_RATE_MIN            48000
  97 #define USE_RATE_MAX            48000
  98 #endif
  99
 100 #if 0 /* CA0106 */
 101 #define USE_FORMATS             SNDRV_PCM_FMTBIT_S16_LE
 102 #define USE_CHANNELS_MIN        2
 103 #define USE_CHANNELS_MAX        2
 104 #define USE_RATE                (SNDRV_PCM_RATE_48000|SNDRV_PCM_RATE_96000|SNDRV_PCM_RATE_192000)
 105 #define USE_RATE_MIN            48000
 106 #define USE_RATE_MAX            192000
 107 #define MAX_BUFFER_SIZE         ((65536-64)*8)
 108 #define MAX_PERIOD_SIZE         (65536-64)
 109 #define USE_PERIODS_MIN         2
 110 #define USE_PERIODS_MAX         8
 111 #endif
 112
 113
 114 /* defaults */
 115 #ifndef MAX_BUFFER_SIZE
 116 #define MAX_BUFFER_SIZE         (64*1024)
 117 #endif
 118 #ifndef MAX_PERIOD_SIZE
 119 #define MAX_PERIOD_SIZE         MAX_BUFFER_SIZE
 120 #endif
 121 #ifndef USE_FORMATS
 122 #define USE_FORMATS             (SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE)
 123 #endif
 124 #ifndef USE_RATE
 125 #define USE_RATE                SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000
 126 #define USE_RATE_MIN            5500
 127 #define USE_RATE_MAX            48000
 128 #endif
 129 #ifndef USE_CHANNELS_MIN
 130 #define USE_CHANNELS_MIN        1
 131 #endif
 132 #ifndef USE_CHANNELS_MAX
 133 #define USE_CHANNELS_MAX        2
 134 #endif
 135 #ifndef USE_PERIODS_MIN
 136 #define USE_PERIODS_MIN         1
 137 #endif
 138 #ifndef USE_PERIODS_MAX
 139 #define USE_PERIODS_MAX         1024
 140 #endif
 141 #ifndef add_playback_constraints
 142 #define add_playback_constraints(x) 0
 143 #endif
 144 #ifndef add_capture_constraints
 145 #define add_capture_constraints(x) 0
 146 #endif
 147
 148 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;      /* Index 0-MAX */
 149 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;       /* ID for this card */
 150 static int enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
 151 static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
 152 static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8};
 153 //static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2};
 154 #ifdef CONFIG_HIGH_RES_TIMERS
 155 static int hrtimer = 1;
 156 #endif
 157 static int fake_buffer = 1;
 158
 159 module_param_array(index, int, NULL, 0444);
 160 MODULE_PARM_DESC(index, "Index value for dummy soundcard.");
 161 module_param_array(id, charp, NULL, 0444);
 162 MODULE_PARM_DESC(id, "ID string for dummy soundcard.");
 163 module_param_array(enable, bool, NULL, 0444);
 164 MODULE_PARM_DESC(enable, "Enable this dummy soundcard.");
 165 module_param_array(pcm_devs, int, NULL, 0444);
 166 MODULE_PARM_DESC(pcm_devs, "PCM devices # (0-4) for dummy driver.");
 167 module_param_array(pcm_substreams, int, NULL, 0444);
 168 MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-16) for dummy driver.");
 169 //module_param_array(midi_devs, int, NULL, 0444);
 170 //MODULE_PARM_DESC(midi_devs, "MIDI devices # (0-2) for dummy driver.");
 171 module_param(fake_buffer, bool, 0444);
 172 MODULE_PARM_DESC(fake_buffer, "Fake buffer allocations.");
 173 #ifdef CONFIG_HIGH_RES_TIMERS
 174 module_param(hrtimer, bool, 0644);
 175 MODULE_PARM_DESC(hrtimer, "Use hrtimer as the timer source.");
 176 #endif
 177
 178 static struct platform_device *devices[SNDRV_CARDS];
 179
 180 #define MIXER_ADDR_MASTER       0
 181 #define MIXER_ADDR_LINE         1
 182 #define MIXER_ADDR_MIC          2
 183 #define MIXER_ADDR_SYNTH        3
 184 #define MIXER_ADDR_CD           4
 185 #define MIXER_ADDR_LAST         4
 186
 187 struct dummy_timer_ops {
 188         int (*create)(struct snd_pcm_substream *);
 189         void (*free)(struct snd_pcm_substream *);
 190         int (*prepare)(struct snd_pcm_substream *);
 191         int (*start)(struct snd_pcm_substream *);
 192         int (*stop)(struct snd_pcm_substream *);
 193         snd_pcm_uframes_t (*pointer)(struct snd_pcm_substream *);
 194 };
 195
 196 struct snd_dummy {
 197         struct snd_card *card;
 198         struct snd_pcm *pcm;
 199         spinlock_t mixer_lock;
 200         int mixer_volume[MIXER_ADDR_LAST+1][2];
 201         int capture_source[MIXER_ADDR_LAST+1][2];
 202         const struct dummy_timer_ops *timer_ops;
 203 };
 204
 205 /*
 206  * system timer interface
 207  */
 208
 209 struct dummy_systimer_pcm {
 210         spinlock_t lock;
 211         struct timer_list timer;
 212         unsigned long base_time;
 213         unsigned int frac_pos;  /* fractional sample position (based HZ) */
 214         unsigned int frac_period_rest;
 215         unsigned int frac_buffer_size;  /* buffer_size * HZ */
 216         unsigned int frac_period_size;  /* period_size * HZ */
 217         unsigned int rate;
 218         int elapsed;
 219         struct snd_pcm_substream *substream;
 220 };
 221
 222 static void dummy_systimer_rearm(struct dummy_systimer_pcm *dpcm)
 223 {
 224         dpcm->timer.expires = jiffies +
 225                 (dpcm->frac_period_rest + dpcm->rate - 1) / dpcm->rate;
 226         add_timer(&dpcm->timer);
 227 }
 228
 229 static void dummy_systimer_update(struct dummy_systimer_pcm *dpcm)
 230 {
 231         unsigned long delta;
 232
 233         delta = jiffies - dpcm->base_time;
 234         if (!delta)
 235                 return;
 236         dpcm->base_time += delta;
 237         delta *= dpcm->rate;
 238         dpcm->frac_pos += delta;
 239         while (dpcm->frac_pos >= dpcm->frac_buffer_size)
 240                 dpcm->frac_pos -= dpcm->frac_buffer_size;
 241         while (dpcm->frac_period_rest <= delta) {
 242                 dpcm->elapsed++;
 243                 dpcm->frac_period_rest += dpcm->frac_period_size;
 244         }
 245         dpcm->frac_period_rest -= delta;
 246 }
 247
 248 static int dummy_systimer_start(struct snd_pcm_substream *substream)
 249 {
 250         struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 251         spin_lock(&dpcm->lock);
 252         dpcm->base_time = jiffies;
 253         dummy_systimer_rearm(dpcm);
 254         spin_unlock(&dpcm->lock);
 255         return 0;
 256 }
 257
 258 static int dummy_systimer_stop(struct snd_pcm_substream *substream)
 259 {
 260         struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 261         spin_lock(&dpcm->lock);
 262         del_timer(&dpcm->timer);
 263         spin_unlock(&dpcm->lock);
 264         return 0;
 265 }
 266
 267 static int dummy_systimer_prepare(struct snd_pcm_substream *substream)
 268 {
 269         struct snd_pcm_runtime *runtime = substream->runtime;
 270         struct dummy_systimer_pcm *dpcm = runtime->private_data;
 271
 272         dpcm->frac_pos = 0;
 273         dpcm->rate = runtime->rate;
 274         dpcm->frac_buffer_size = runtime->buffer_size * HZ;
 275         dpcm->frac_period_size = runtime->period_size * HZ;
 276         dpcm->frac_period_rest = dpcm->frac_period_size;
 277         dpcm->elapsed = 0;
 278
 279         return 0;
 280 }
 281
 282 static void dummy_systimer_callback(unsigned long data)
 283 {
 284         struct dummy_systimer_pcm *dpcm = (struct dummy_systimer_pcm *)data;
 285         unsigned long flags;
 286         int elapsed = 0;
 287
 288         spin_lock_irqsave(&dpcm->lock, flags);
 289         dummy_systimer_update(dpcm);
 290         dummy_systimer_rearm(dpcm);
 291         elapsed = dpcm->elapsed;
 292         dpcm->elapsed = 0;
 293         spin_unlock_irqrestore(&dpcm->lock, flags);
 294         if (elapsed)
 295                 snd_pcm_period_elapsed(dpcm->substream);
 296 }
 297
 298 static snd_pcm_uframes_t
 299 dummy_systimer_pointer(struct snd_pcm_substream *substream)
 300 {
 301         struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 302         snd_pcm_uframes_t pos;
 303
 304         spin_lock(&dpcm->lock);
 305         dummy_systimer_update(dpcm);
 306         pos = dpcm->frac_pos / HZ;
 307         spin_unlock(&dpcm->lock);
 308         return pos;
 309 }
 310
 311 static int dummy_systimer_create(struct snd_pcm_substream *substream)
 312 {
 313         struct dummy_systimer_pcm *dpcm;
 314
 315         dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 316         if (!dpcm)
 317                 return -ENOMEM;
 318         substream->runtime->private_data = dpcm;
 319         init_timer(&dpcm->timer);
 320         dpcm->timer.data = (unsigned long) dpcm;
 321         dpcm->timer.function = dummy_systimer_callback;
 322         spin_lock_init(&dpcm->lock);
 323         dpcm->substream = substream;
 324         return 0;
 325 }
 326
 327 static void dummy_systimer_free(struct snd_pcm_substream *substream)
 328 {
 329         kfree(substream->runtime->private_data);
 330 }
 331
 332 static struct dummy_timer_ops dummy_systimer_ops = {
 333         .create =       dummy_systimer_create,
 334         .free =         dummy_systimer_free,
 335         .prepare =      dummy_systimer_prepare,
 336         .start =        dummy_systimer_start,
 337         .stop =         dummy_systimer_stop,
 338         .pointer =      dummy_systimer_pointer,
 339 };
 340
 341 #ifdef CONFIG_HIGH_RES_TIMERS
 342 /*
 343  * hrtimer interface
 344  */
 345
 346 struct dummy_hrtimer_pcm {
 347         ktime_t base_time;
 348         ktime_t period_time;
 349         atomic_t running;
 350         struct hrtimer timer;
 351         struct tasklet_struct tasklet;
 352         struct snd_pcm_substream *substream;
 353 };
 354
 355 static void dummy_hrtimer_pcm_elapsed(unsigned long priv)
 356 {
 357         struct dummy_hrtimer_pcm *dpcm = (struct dummy_hrtimer_pcm *)priv;
 358         if (atomic_read(&dpcm->running))
 359                 snd_pcm_period_elapsed(dpcm->substream);
 360 }
 361
 362 static enum hrtimer_restart dummy_hrtimer_callback(struct hrtimer *timer)
 363 {
 364         struct dummy_hrtimer_pcm *dpcm;
 365
 366         dpcm = container_of(timer, struct dummy_hrtimer_pcm, timer);
 367         if (!atomic_read(&dpcm->running))
 368                 return HRTIMER_NORESTART;
 369         tasklet_schedule(&dpcm->tasklet);
 370         hrtimer_forward_now(timer, dpcm->period_time);
 371         return HRTIMER_RESTART;
 372 }
 373
 374 static int dummy_hrtimer_start(struct snd_pcm_substream *substream)
 375 {
 376         struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 377
 378         dpcm->base_time = hrtimer_cb_get_time(&dpcm->timer);
 379         hrtimer_start(&dpcm->timer, dpcm->period_time, HRTIMER_MODE_REL);
 380         atomic_set(&dpcm->running, 1);
 381         return 0;
 382 }
 383
 384 static int dummy_hrtimer_stop(struct snd_pcm_substream *substream)
 385 {
 386         struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 387
 388         atomic_set(&dpcm->running, 0);
 389         hrtimer_cancel(&dpcm->timer);
 390         return 0;
 391 }
 392
 393 static inline void dummy_hrtimer_sync(struct dummy_hrtimer_pcm *dpcm)
 394 {
 395         tasklet_kill(&dpcm->tasklet);
 396 }
 397
 398 static snd_pcm_uframes_t
 399 dummy_hrtimer_pointer(struct snd_pcm_substream *substream)
 400 {
 401         struct snd_pcm_runtime *runtime = substream->runtime;
 402         struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 403         u64 delta;
 404         u32 pos;
 405
 406         delta = ktime_us_delta(hrtimer_cb_get_time(&dpcm->timer),
 407                                dpcm->base_time);
 408         delta = div_u64(delta * runtime->rate + 999999, 1000000);
 409         div_u64_rem(delta, runtime->buffer_size, &pos);
 410         return pos;
 411 }
 412
 413 static int dummy_hrtimer_prepare(struct snd_pcm_substream *substream)
 414 {
 415         struct snd_pcm_runtime *runtime = substream->runtime;
 416         struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 417         unsigned int period, rate;
 418         long sec;
 419         unsigned long nsecs;
 420
 421         dummy_hrtimer_sync(dpcm);
 422         period = runtime->period_size;
 423         rate = runtime->rate;
 424         sec = period / rate;
 425         period %= rate;
 426         nsecs = div_u64((u64)period * 1000000000UL + rate - 1, rate);
 427         dpcm->period_time = ktime_set(sec, nsecs);
 428
 429         return 0;
 430 }
 431
 432 static int dummy_hrtimer_create(struct snd_pcm_substream *substream)
 433 {
 434         struct dummy_hrtimer_pcm *dpcm;
 435
 436         dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 437         if (!dpcm)
 438                 return -ENOMEM;
 439         substream->runtime->private_data = dpcm;
 440         hrtimer_init(&dpcm->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 441         dpcm->timer.function = dummy_hrtimer_callback;
 442         dpcm->substream = substream;
 443         atomic_set(&dpcm->running, 0);
 444         tasklet_init(&dpcm->tasklet, dummy_hrtimer_pcm_elapsed,
 445                      (unsigned long)dpcm);
 446         return 0;
 447 }
 448
 449 static void dummy_hrtimer_free(struct snd_pcm_substream *substream)
 450 {
 451         struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 452         dummy_hrtimer_sync(dpcm);
 453         kfree(dpcm);
 454 }
 455
 456 static struct dummy_timer_ops dummy_hrtimer_ops = {
 457         .create =       dummy_hrtimer_create,
 458         .free =         dummy_hrtimer_free,
 459         .prepare =      dummy_hrtimer_prepare,
 460         .start =        dummy_hrtimer_start,
 461         .stop =         dummy_hrtimer_stop,
 462         .pointer =      dummy_hrtimer_pointer,
 463 };
 464
 465 #endif /* CONFIG_HIGH_RES_TIMERS */
 466
 467 /*
 468  * PCM interface
 469  */
 470
 471 static int dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 472 {
 473         struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 474
 475         switch (cmd) {
 476         case SNDRV_PCM_TRIGGER_START:
 477         case SNDRV_PCM_TRIGGER_RESUME:
 478                 return dummy->timer_ops->start(substream);
 479         case SNDRV_PCM_TRIGGER_STOP:
 480         case SNDRV_PCM_TRIGGER_SUSPEND:
 481                 return dummy->timer_ops->stop(substream);
 482         }
 483         return -EINVAL;
 484 }
 485
 486 static int dummy_pcm_prepare(struct snd_pcm_substream *substream)
 487 {
 488         struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 489
 490         return dummy->timer_ops->prepare(substream);
 491 }
 492
 493 static snd_pcm_uframes_t dummy_pcm_pointer(struct snd_pcm_substream *substream)
 494 {
 495         struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 496
 497         return dummy->timer_ops->pointer(substream);
 498 }
 499
 500 static struct snd_pcm_hardware dummy_pcm_hardware = {
 501         .info =                 (SNDRV_PCM_INFO_MMAP |
 502                                  SNDRV_PCM_INFO_INTERLEAVED |
 503                                  SNDRV_PCM_INFO_RESUME |
 504                                  SNDRV_PCM_INFO_MMAP_VALID),
 505         .formats =              USE_FORMATS,
 506         .rates =                USE_RATE,
 507         .rate_min =             USE_RATE_MIN,
 508         .rate_max =             USE_RATE_MAX,
 509         .channels_min =         USE_CHANNELS_MIN,
 510         .channels_max =         USE_CHANNELS_MAX,
 511         .buffer_bytes_max =     MAX_BUFFER_SIZE,
 512         .period_bytes_min =     64,
 513         .period_bytes_max =     MAX_PERIOD_SIZE,
 514         .periods_min =          USE_PERIODS_MIN,
 515         .periods_max =          USE_PERIODS_MAX,
 516         .fifo_size =            0,
 517 };
 518
 519 static int dummy_pcm_hw_params(struct snd_pcm_substream *substream,
 520                                struct snd_pcm_hw_params *hw_params)
 521 {
 522         if (fake_buffer) {
 523                 /* runtime->dma_bytes has to be set manually to allow mmap */
 524                 substream->runtime->dma_bytes = params_buffer_bytes(hw_params);
 525                 return 0;
 526         }
 527         return snd_pcm_lib_malloc_pages(substream,
 528                                         params_buffer_bytes(hw_params));
 529 }
 530
 531 static int dummy_pcm_hw_free(struct snd_pcm_substream *substream)
 532 {
 533         if (fake_buffer)
 534                 return 0;
 535         return snd_pcm_lib_free_pages(substream);
 536 }
 537
 538 static int dummy_pcm_open(struct snd_pcm_substream *substream)
 539 {
 540         struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 541         struct snd_pcm_runtime *runtime = substream->runtime;
 542         int err;
 543
 544         dummy->timer_ops = &dummy_systimer_ops;
 545 #ifdef CONFIG_HIGH_RES_TIMERS
 546         if (hrtimer)
 547                 dummy->timer_ops = &dummy_hrtimer_ops;
 548 #endif
 549
 550         err = dummy->timer_ops->create(substream);
 551         if (err < 0)
 552                 return err;
 553
 554         runtime->hw = dummy_pcm_hardware;
 555         if (substream->pcm->device & 1) {
 556                 runtime->hw.info &= ~SNDRV_PCM_INFO_INTERLEAVED;
 557                 runtime->hw.info |= SNDRV_PCM_INFO_NONINTERLEAVED;
 558         }
 559         if (substream->pcm->device & 2)
 560                 runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
 561                                       SNDRV_PCM_INFO_MMAP_VALID);
 562
 563         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 564                 err = add_playback_constraints(substream->runtime);
 565         else
 566                 err = add_capture_constraints(substream->runtime);
 567         if (err < 0) {
 568                 dummy->timer_ops->free(substream);
 569                 return err;
 570         }
 571         return 0;
 572 }
 573
 574 static int dummy_pcm_close(struct snd_pcm_substream *substream)
 575 {
 576         struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 577         dummy->timer_ops->free(substream);
 578         return 0;
 579 }
 580
 581 /*
 582  * dummy buffer handling
 583  */
 584
 585 static void *dummy_page[2];
 586
 587 static void free_fake_buffer(void)
 588 {
 589         if (fake_buffer) {
 590                 int i;
 591                 for (i = 0; i < 2; i++)
 592                         if (dummy_page[i]) {
 593                                 free_page((unsigned long)dummy_page[i]);
 594                                 dummy_page[i] = NULL;
 595                         }
 596         }
 597 }
 598
 599 static int alloc_fake_buffer(void)
 600 {
 601         int i;
 602
 603         if (!fake_buffer)
 604                 return 0;
 605         for (i = 0; i < 2; i++) {
 606                 dummy_page[i] = (void *)get_zeroed_page(GFP_KERNEL);
 607                 if (!dummy_page[i]) {
 608                         free_fake_buffer();
 609                         return -ENOMEM;
 610                 }
 611         }
 612         return 0;
 613 }
 614
 615 static int dummy_pcm_copy(struct snd_pcm_substream *substream,
 616                           int channel, snd_pcm_uframes_t pos,
 617                           void __user *dst, snd_pcm_uframes_t count)
 618 {
 619         return 0; /* do nothing */
 620 }
 621
 622 static int dummy_pcm_silence(struct snd_pcm_substream *substream,
 623                              int channel, snd_pcm_uframes_t pos,
 624                              snd_pcm_uframes_t count)
 625 {
 626         return 0; /* do nothing */
 627 }
 628
 629 static struct page *dummy_pcm_page(struct snd_pcm_substream *substream,
 630                                    unsigned long offset)
 631 {
 632         return virt_to_page(dummy_page[substream->stream]); /* the same page */
 633 }
 634
 635 static struct snd_pcm_ops dummy_pcm_ops = {
 636         .open =         dummy_pcm_open,
 637         .close =        dummy_pcm_close,
 638         .ioctl =        snd_pcm_lib_ioctl,
 639         .hw_params =    dummy_pcm_hw_params,
 640         .hw_free =      dummy_pcm_hw_free,
 641         .prepare =      dummy_pcm_prepare,
 642         .trigger =      dummy_pcm_trigger,
 643         .pointer =      dummy_pcm_pointer,
 644 };
 645
 646 static struct snd_pcm_ops dummy_pcm_ops_no_buf = {
 647         .open =         dummy_pcm_open,
 648         .close =        dummy_pcm_close,
 649         .ioctl =        snd_pcm_lib_ioctl,
 650         .hw_params =    dummy_pcm_hw_params,
 651         .hw_free =      dummy_pcm_hw_free,
 652         .prepare =      dummy_pcm_prepare,
 653         .trigger =      dummy_pcm_trigger,
 654         .pointer =      dummy_pcm_pointer,
 655         .copy =         dummy_pcm_copy,
 656         .silence =      dummy_pcm_silence,
 657         .page =         dummy_pcm_page,
 658 };
 659
 660 static int __devinit snd_card_dummy_pcm(struct snd_dummy *dummy, int device,
 661                                         int substreams)
 662 {
 663         struct snd_pcm *pcm;
 664         struct snd_pcm_ops *ops;
 665         int err;
 666
 667         err = snd_pcm_new(dummy->card, "Dummy PCM", device,
 668                                substreams, substreams, &pcm);
 669         if (err < 0)
 670                 return err;
 671         dummy->pcm = pcm;
 672         if (fake_buffer)
 673                 ops = &dummy_pcm_ops_no_buf;
 674         else
 675                 ops = &dummy_pcm_ops;
 676         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, ops);
 677         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, ops);
 678         pcm->private_data = dummy;
 679         pcm->info_flags = 0;
 680         strcpy(pcm->name, "Dummy PCM");
 681         if (!fake_buffer) {
 682                 snd_pcm_lib_preallocate_pages_for_all(pcm,
 683                         SNDRV_DMA_TYPE_CONTINUOUS,
 684                         snd_dma_continuous_data(GFP_KERNEL),
 685                         0, 64*1024);
 686         }
 687         return 0;
 688 }
 689
 690 /*
 691  * mixer interface
 692  */
 693
 694 #define DUMMY_VOLUME(xname, xindex, addr) \
 695 { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
 696   .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ, \
 697   .name = xname, .index = xindex, \
 698   .info = snd_dummy_volume_info, \
 699   .get = snd_dummy_volume_get, .put = snd_dummy_volume_put, \
 700   .private_value = addr, \
 701   .tlv = { .p = db_scale_dummy } }
 702
 703 static int snd_dummy_volume_info(struct snd_kcontrol *kcontrol,
 704                                  struct snd_ctl_elem_info *uinfo)
 705 {
 706         uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 707         uinfo->count = 2;
 708         uinfo->value.integer.min = -50;
 709         uinfo->value.integer.max = 100;
 710         return 0;
 711 }
 712
 713 static int snd_dummy_volume_get(struct snd_kcontrol *kcontrol,
 714                                 struct snd_ctl_elem_value *ucontrol)
 715 {
 716         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 717         int addr = kcontrol->private_value;
 718
 719         spin_lock_irq(&dummy->mixer_lock);
 720         ucontrol->value.integer.value[0] = dummy->mixer_volume[addr][0];
 721         ucontrol->value.integer.value[1] = dummy->mixer_volume[addr][1];
 722         spin_unlock_irq(&dummy->mixer_lock);
 723         return 0;
 724 }
 725
 726 static int snd_dummy_volume_put(struct snd_kcontrol *kcontrol,
 727                                 struct snd_ctl_elem_value *ucontrol)
 728 {
 729         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 730         int change, addr = kcontrol->private_value;
 731         int left, right;
 732
 733         left = ucontrol->value.integer.value[0];
 734         if (left < -50)
 735                 left = -50;
 736         if (left > 100)
 737                 left = 100;
 738         right = ucontrol->value.integer.value[1];
 739         if (right < -50)
 740                 right = -50;
 741         if (right > 100)
 742                 right = 100;
 743         spin_lock_irq(&dummy->mixer_lock);
 744         change = dummy->mixer_volume[addr][0] != left ||
 745                  dummy->mixer_volume[addr][1] != right;
 746         dummy->mixer_volume[addr][0] = left;
 747         dummy->mixer_volume[addr][1] = right;
 748         spin_unlock_irq(&dummy->mixer_lock);
 749         return change;
 750 }
 751
 752 static const DECLARE_TLV_DB_SCALE(db_scale_dummy, -4500, 30, 0);
 753
 754 #define DUMMY_CAPSRC(xname, xindex, addr) \
 755 { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
 756   .info = snd_dummy_capsrc_info, \
 757   .get = snd_dummy_capsrc_get, .put = snd_dummy_capsrc_put, \
 758   .private_value = addr }
 759
 760 #define snd_dummy_capsrc_info   snd_ctl_boolean_stereo_info
 761
 762 static int snd_dummy_capsrc_get(struct snd_kcontrol *kcontrol,
 763                                 struct snd_ctl_elem_value *ucontrol)
 764 {
 765         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 766         int addr = kcontrol->private_value;
 767
 768         spin_lock_irq(&dummy->mixer_lock);
 769         ucontrol->value.integer.value[0] = dummy->capture_source[addr][0];
 770         ucontrol->value.integer.value[1] = dummy->capture_source[addr][1];
 771         spin_unlock_irq(&dummy->mixer_lock);
 772         return 0;
 773 }
 774
 775 static int snd_dummy_capsrc_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
 776 {
 777         struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 778         int change, addr = kcontrol->private_value;
 779         int left, right;
 780
 781         left = ucontrol->value.integer.value[0] & 1;
 782         right = ucontrol->value.integer.value[1] & 1;
 783         spin_lock_irq(&dummy->mixer_lock);
 784         change = dummy->capture_source[addr][0] != left &&
 785                  dummy->capture_source[addr][1] != right;
 786         dummy->capture_source[addr][0] = left;
 787         dummy->capture_source[addr][1] = right;
 788         spin_unlock_irq(&dummy->mixer_lock);
 789         return change;
 790 }
 791
 792 static struct snd_kcontrol_new snd_dummy_controls[] = {
 793 DUMMY_VOLUME("Master Volume", 0, MIXER_ADDR_MASTER),
 794 DUMMY_CAPSRC("Master Capture Switch", 0, MIXER_ADDR_MASTER),
 795 DUMMY_VOLUME("Synth Volume", 0, MIXER_ADDR_SYNTH),
 796 DUMMY_CAPSRC("Synth Capture Switch", 0, MIXER_ADDR_SYNTH),
 797 DUMMY_VOLUME("Line Volume", 0, MIXER_ADDR_LINE),
 798 DUMMY_CAPSRC("Line Capture Switch", 0, MIXER_ADDR_LINE),
 799 DUMMY_VOLUME("Mic Volume", 0, MIXER_ADDR_MIC),
 800 DUMMY_CAPSRC("Mic Capture Switch", 0, MIXER_ADDR_MIC),
 801 DUMMY_VOLUME("CD Volume", 0, MIXER_ADDR_CD),
 802 DUMMY_CAPSRC("CD Capture Switch", 0, MIXER_ADDR_CD)
 803 };
 804
 805 static int __devinit snd_card_dummy_new_mixer(struct snd_dummy *dummy)
 806 {
 807         struct snd_card *card = dummy->card;
 808         unsigned int idx;
 809         int err;
 810
 811         if (snd_BUG_ON(!dummy))
 812                 return -EINVAL;
 813         spin_lock_init(&dummy->mixer_lock);
 814         strcpy(card->mixername, "Dummy Mixer");
 815
 816         for (idx = 0; idx < ARRAY_SIZE(snd_dummy_controls); idx++) {
 817                 err = snd_ctl_add(card, snd_ctl_new1(&snd_dummy_controls[idx], dummy));
 818                 if (err < 0)
 819                         return err;
 820         }
 821         return 0;
 822 }
 823
 824 #if defined(CONFIG_SND_DEBUG) && defined(CONFIG_PROC_FS)
 825 /*
 826  * proc interface
 827  */
 828 static void print_formats(struct snd_info_buffer *buffer)
 829 {
 830         int i;
 831
 832         for (i = 0; i < SNDRV_PCM_FORMAT_LAST; i++) {
 833                 if (dummy_pcm_hardware.formats & (1ULL << i))
 834                         snd_iprintf(buffer, " %s", snd_pcm_format_name(i));
 835         }
 836 }
 837
 838 static void print_rates(struct snd_info_buffer *buffer)
 839 {
 840         static int rates[] = {
 841                 5512, 8000, 11025, 16000, 22050, 32000, 44100, 48000,
 842                 64000, 88200, 96000, 176400, 192000,
 843         };
 844         int i;
 845
 846         if (dummy_pcm_hardware.rates & SNDRV_PCM_RATE_CONTINUOUS)
 847                 snd_iprintf(buffer, " continuous");
 848         if (dummy_pcm_hardware.rates & SNDRV_PCM_RATE_KNOT)
 849                 snd_iprintf(buffer, " knot");
 850         for (i = 0; i < ARRAY_SIZE(rates); i++)
 851                 if (dummy_pcm_hardware.rates & (1 << i))
 852                         snd_iprintf(buffer, " %d", rates[i]);
 853 }
 854
 855 #define get_dummy_int_ptr(ofs) \
 856         (unsigned int *)((char *)&dummy_pcm_hardware + (ofs))
 857 #define get_dummy_ll_ptr(ofs) \
 858         (unsigned long long *)((char *)&dummy_pcm_hardware + (ofs))
 859
 860 struct dummy_hw_field {
 861         const char *name;
 862         const char *format;
 863         unsigned int offset;
 864         unsigned int size;
 865 };
 866 #define FIELD_ENTRY(item, fmt) {                   \
 867         .name = #item,                             \
 868         .format = fmt,                             \
 869         .offset = offsetof(struct snd_pcm_hardware, item), \
 870         .size = sizeof(dummy_pcm_hardware.item) }
 871
 872 static struct dummy_hw_field fields[] = {
 873         FIELD_ENTRY(formats, "%#llx"),
 874         FIELD_ENTRY(rates, "%#x"),
 875         FIELD_ENTRY(rate_min, "%d"),
 876         FIELD_ENTRY(rate_max, "%d"),
 877         FIELD_ENTRY(channels_min, "%d"),
 878         FIELD_ENTRY(channels_max, "%d"),
 879         FIELD_ENTRY(buffer_bytes_max, "%ld"),
 880         FIELD_ENTRY(period_bytes_min, "%ld"),
 881         FIELD_ENTRY(period_bytes_max, "%ld"),
 882         FIELD_ENTRY(periods_min, "%d"),
 883         FIELD_ENTRY(periods_max, "%d"),
 884 };
 885
 886 static void dummy_proc_read(struct snd_info_entry *entry,
 887                             struct snd_info_buffer *buffer)
 888 {
 889         int i;
 890
 891         for (i = 0; i < ARRAY_SIZE(fields); i++) {
 892                 snd_iprintf(buffer, "%s ", fields[i].name);
 893                 if (fields[i].size == sizeof(int))
 894                         snd_iprintf(buffer, fields[i].format,
 895                                     *get_dummy_int_ptr(fields[i].offset));
 896                 else
 897                         snd_iprintf(buffer, fields[i].format,
 898                                     *get_dummy_ll_ptr(fields[i].offset));
 899                 if (!strcmp(fields[i].name, "formats"))
 900                         print_formats(buffer);
 901                 else if (!strcmp(fields[i].name, "rates"))
 902                         print_rates(buffer);
 903                 snd_iprintf(buffer, "\n");
 904         }
 905 }
 906
 907 static void dummy_proc_write(struct snd_info_entry *entry,
 908                              struct snd_info_buffer *buffer)
 909 {
 910         char line[64];
 911
 912         while (!snd_info_get_line(buffer, line, sizeof(line))) {
 913                 char item[20];
 914                 const char *ptr;
 915                 unsigned long long val;
 916                 int i;
 917
 918                 ptr = snd_info_get_str(item, line, sizeof(item));
 919                 for (i = 0; i < ARRAY_SIZE(fields); i++) {
 920                         if (!strcmp(item, fields[i].name))
 921                                 break;
 922                 }
 923                 if (i >= ARRAY_SIZE(fields))
 924                         continue;
 925                 snd_info_get_str(item, ptr, sizeof(item));
 926                 if (strict_strtoull(item, 0, &val))
 927                         continue;
 928                 if (fields[i].size == sizeof(int))
 929                         *get_dummy_int_ptr(fields[i].offset) = val;
 930                 else
 931                         *get_dummy_ll_ptr(fields[i].offset) = val;
 932         }
 933 }
 934
 935 static void __devinit dummy_proc_init(struct snd_dummy *chip)
 936 {
 937         struct snd_info_entry *entry;
 938
 939         if (!snd_card_proc_new(chip->card, "dummy_pcm", &entry)) {
 940                 snd_info_set_text_ops(entry, chip, dummy_proc_read);
 941                 entry->c.text.write = dummy_proc_write;
 942                 entry->mode |= S_IWUSR;
 943         }
 944 }
 945 #else
 946 #define dummy_proc_init(x)
 947 #endif /* CONFIG_SND_DEBUG && CONFIG_PROC_FS */
 948
 949 static int __devinit snd_dummy_probe(struct platform_device *devptr)
 950 {
 951         struct snd_card *card;
 952         struct snd_dummy *dummy;
 953         int idx, err;
 954         int dev = devptr->id;
 955
 956         err = snd_card_create(index[dev], id[dev], THIS_MODULE,
 957                               sizeof(struct snd_dummy), &card);
 958         if (err < 0)
 959                 return err;
 960         dummy = card->private_data;
 961         dummy->card = card;
 962         for (idx = 0; idx < MAX_PCM_DEVICES && idx < pcm_devs[dev]; idx++) {
 963                 if (pcm_substreams[dev] < 1)
 964                         pcm_substreams[dev] = 1;
 965                 if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
 966                         pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
 967                 err = snd_card_dummy_pcm(dummy, idx, pcm_substreams[dev]);
 968                 if (err < 0)
 969                         goto __nodev;
 970         }
 971         err = snd_card_dummy_new_mixer(dummy);
 972         if (err < 0)
 973                 goto __nodev;
 974         strcpy(card->driver, "Dummy");
 975         strcpy(card->shortname, "Dummy");
 976         sprintf(card->longname, "Dummy %i", dev + 1);
 977
 978         dummy_proc_init(dummy);
 979
 980         snd_card_set_dev(card, &devptr->dev);
 981
 982         err = snd_card_register(card);
 983         if (err == 0) {
 984                 platform_set_drvdata(devptr, card);
 985                 return 0;
 986         }
 987       __nodev:
 988         snd_card_free(card);
 989         return err;
 990 }
 991
 992 static int __devexit snd_dummy_remove(struct platform_device *devptr)
 993 {
 994         snd_card_free(platform_get_drvdata(devptr));
 995         platform_set_drvdata(devptr, NULL);
 996         return 0;
 997 }
 998
 999 #ifdef CONFIG_PM
1000 static int snd_dummy_suspend(struct platform_device *pdev, pm_message_t state)
1001 {
1002         struct snd_card *card = platform_get_drvdata(pdev);
1003         struct snd_dummy *dummy = card->private_data;
1004
1005         snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
1006         snd_pcm_suspend_all(dummy->pcm);
1007         return 0;
1008 }
1009
1010 static int snd_dummy_resume(struct platform_device *pdev)
1011 {
1012         struct snd_card *card = platform_get_drvdata(pdev);
1013
1014         snd_power_change_state(card, SNDRV_CTL_POWER_D0);
1015         return 0;
1016 }
1017 #endif
1018
1019 #define SND_DUMMY_DRIVER        "snd_dummy"
1020
1021 static struct platform_driver snd_dummy_driver = {
1022         .probe          = snd_dummy_probe,
1023         .remove         = __devexit_p(snd_dummy_remove),
1024 #ifdef CONFIG_PM
1025         .suspend        = snd_dummy_suspend,
1026         .resume         = snd_dummy_resume,
1027 #endif
1028         .driver         = {
1029                 .name   = SND_DUMMY_DRIVER
1030         },
1031 };
1032
1033 static void snd_dummy_unregister_all(void)
1034 {
1035         int i;
1036
1037         for (i = 0; i < ARRAY_SIZE(devices); ++i)
1038                 platform_device_unregister(devices[i]);
1039         platform_driver_unregister(&snd_dummy_driver);
1040         free_fake_buffer();
1041 }
1042
1043 static int __init alsa_card_dummy_init(void)
1044 {
1045         int i, cards, err;
1046
1047         err = platform_driver_register(&snd_dummy_driver);
1048         if (err < 0)
1049                 return err;
1050
1051         err = alloc_fake_buffer();
1052         if (err < 0) {
1053                 platform_driver_unregister(&snd_dummy_driver);
1054                 return err;
1055         }
1056
1057         cards = 0;
1058         for (i = 0; i < SNDRV_CARDS; i++) {
1059                 struct platform_device *device;
1060                 if (! enable[i])
1061                         continue;
1062                 device = platform_device_register_simple(SND_DUMMY_DRIVER,
1063                                                          i, NULL, 0);
1064                 if (IS_ERR(device))
1065                         continue;
1066                 if (!platform_get_drvdata(device)) {
1067                         platform_device_unregister(device);
1068                         continue;
1069                 }
1070                 devices[i] = device;
1071                 cards++;
1072         }
1073         if (!cards) {
1074 #ifdef MODULE
1075                 printk(KERN_ERR "Dummy soundcard not found or device busy\n");
1076 #endif
1077                 snd_dummy_unregister_all();
1078                 return -ENODEV;
1079         }
1080         return 0;
1081 }
1082
1083 static void __exit alsa_card_dummy_exit(void)
1084 {
1085         snd_dummy_unregister_all();
1086 }
1087
1088 module_init(alsa_card_dummy_init)
1089 module_exit(alsa_card_dummy_exit)