linux/sound/drivers/dummy.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  Dummy soundcard
   4 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   5 */
   6
   7#include <linux/init.h>
   8#include <linux/err.h>
   9#include <linux/platform_device.h>
  10#include <linux/jiffies.h>
  11#include <linux/slab.h>
  12#include <linux/time.h>
  13#include <linux/wait.h>
  14#include <linux/hrtimer.h>
  15#include <linux/math64.h>
  16#include <linux/module.h>
  17#include <sound/core.h>
  18#include <sound/control.h>
  19#include <sound/tlv.h>
  20#include <sound/pcm.h>
  21#include <sound/rawmidi.h>
  22#include <sound/info.h>
  23#include <sound/initval.h>
  24
  25MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
  26MODULE_DESCRIPTION("Dummy soundcard (/dev/null)");
  27MODULE_LICENSE("GPL");
  28MODULE_SUPPORTED_DEVICE("{{ALSA,Dummy soundcard}}");
  29
  30#define MAX_PCM_DEVICES         4
  31#define MAX_PCM_SUBSTREAMS      128
  32#define MAX_MIDI_DEVICES        2
  33
  34/* defaults */
  35#define MAX_BUFFER_SIZE         (64*1024)
  36#define MIN_PERIOD_SIZE         64
  37#define MAX_PERIOD_SIZE         MAX_BUFFER_SIZE
  38#define USE_FORMATS             (SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE)
  39#define USE_RATE                SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000
  40#define USE_RATE_MIN            5500
  41#define USE_RATE_MAX            48000
  42#define USE_CHANNELS_MIN        1
  43#define USE_CHANNELS_MAX        2
  44#define USE_PERIODS_MIN         1
  45#define USE_PERIODS_MAX         1024
  46
  47static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;      /* Index 0-MAX */
  48static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;       /* ID for this card */
  49static bool enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
  50static char *model[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = NULL};
  51static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
  52static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8};
  53//static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2};
  54#ifdef CONFIG_HIGH_RES_TIMERS
  55static bool hrtimer = 1;
  56#endif
  57static bool fake_buffer = 1;
  58
  59module_param_array(index, int, NULL, 0444);
  60MODULE_PARM_DESC(index, "Index value for dummy soundcard.");
  61module_param_array(id, charp, NULL, 0444);
  62MODULE_PARM_DESC(id, "ID string for dummy soundcard.");
  63module_param_array(enable, bool, NULL, 0444);
  64MODULE_PARM_DESC(enable, "Enable this dummy soundcard.");
  65module_param_array(model, charp, NULL, 0444);
  66MODULE_PARM_DESC(model, "Soundcard model.");
  67module_param_array(pcm_devs, int, NULL, 0444);
  68MODULE_PARM_DESC(pcm_devs, "PCM devices # (0-4) for dummy driver.");
  69module_param_array(pcm_substreams, int, NULL, 0444);
  70MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-128) for dummy driver.");
  71//module_param_array(midi_devs, int, NULL, 0444);
  72//MODULE_PARM_DESC(midi_devs, "MIDI devices # (0-2) for dummy driver.");
  73module_param(fake_buffer, bool, 0444);
  74MODULE_PARM_DESC(fake_buffer, "Fake buffer allocations.");
  75#ifdef CONFIG_HIGH_RES_TIMERS
  76module_param(hrtimer, bool, 0644);
  77MODULE_PARM_DESC(hrtimer, "Use hrtimer as the timer source.");
  78#endif
  79
  80static struct platform_device *devices[SNDRV_CARDS];
  81
  82#define MIXER_ADDR_MASTER       0
  83#define MIXER_ADDR_LINE         1
  84#define MIXER_ADDR_MIC          2
  85#define MIXER_ADDR_SYNTH        3
  86#define MIXER_ADDR_CD           4
  87#define MIXER_ADDR_LAST         4
  88
  89struct dummy_timer_ops {
  90        int (*create)(struct snd_pcm_substream *);
  91        void (*free)(struct snd_pcm_substream *);
  92        int (*prepare)(struct snd_pcm_substream *);
  93        int (*start)(struct snd_pcm_substream *);
  94        int (*stop)(struct snd_pcm_substream *);
  95        snd_pcm_uframes_t (*pointer)(struct snd_pcm_substream *);
  96};
  97
  98#define get_dummy_ops(substream) \
  99        (*(const struct dummy_timer_ops **)(substream)->runtime->private_data)
 100
 101struct dummy_model {
 102        const char *name;
 103        int (*playback_constraints)(struct snd_pcm_runtime *runtime);
 104        int (*capture_constraints)(struct snd_pcm_runtime *runtime);
 105        u64 formats;
 106        size_t buffer_bytes_max;
 107        size_t period_bytes_min;
 108        size_t period_bytes_max;
 109        unsigned int periods_min;
 110        unsigned int periods_max;
 111        unsigned int rates;
 112        unsigned int rate_min;
 113        unsigned int rate_max;
 114        unsigned int channels_min;
 115        unsigned int channels_max;
 116};
 117
 118struct snd_dummy {
 119        struct snd_card *card;
 120        const struct dummy_model *model;
 121        struct snd_pcm *pcm;
 122        struct snd_pcm_hardware pcm_hw;
 123        spinlock_t mixer_lock;
 124        int mixer_volume[MIXER_ADDR_LAST+1][2];
 125        int capture_source[MIXER_ADDR_LAST+1][2];
 126        int iobox;
 127        struct snd_kcontrol *cd_volume_ctl;
 128        struct snd_kcontrol *cd_switch_ctl;
 129};
 130
 131/*
 132 * card models
 133 */
 134
 135static int emu10k1_playback_constraints(struct snd_pcm_runtime *runtime)
 136{
 137        int err;
 138        err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 139        if (err < 0)
 140                return err;
 141        err = snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 256, UINT_MAX);
 142        if (err < 0)
 143                return err;
 144        return 0;
 145}
 146
 147static const struct dummy_model model_emu10k1 = {
 148        .name = "emu10k1",
 149        .playback_constraints = emu10k1_playback_constraints,
 150        .buffer_bytes_max = 128 * 1024,
 151};
 152
 153static const struct dummy_model model_rme9652 = {
 154        .name = "rme9652",
 155        .buffer_bytes_max = 26 * 64 * 1024,
 156        .formats = SNDRV_PCM_FMTBIT_S32_LE,
 157        .channels_min = 26,
 158        .channels_max = 26,
 159        .periods_min = 2,
 160        .periods_max = 2,
 161};
 162
 163static const struct dummy_model model_ice1712 = {
 164        .name = "ice1712",
 165        .buffer_bytes_max = 256 * 1024,
 166        .formats = SNDRV_PCM_FMTBIT_S32_LE,
 167        .channels_min = 10,
 168        .channels_max = 10,
 169        .periods_min = 1,
 170        .periods_max = 1024,
 171};
 172
 173static const struct dummy_model model_uda1341 = {
 174        .name = "uda1341",
 175        .buffer_bytes_max = 16380,
 176        .formats = SNDRV_PCM_FMTBIT_S16_LE,
 177        .channels_min = 2,
 178        .channels_max = 2,
 179        .periods_min = 2,
 180        .periods_max = 255,
 181};
 182
 183static const struct dummy_model model_ac97 = {
 184        .name = "ac97",
 185        .formats = SNDRV_PCM_FMTBIT_S16_LE,
 186        .channels_min = 2,
 187        .channels_max = 2,
 188        .rates = SNDRV_PCM_RATE_48000,
 189        .rate_min = 48000,
 190        .rate_max = 48000,
 191};
 192
 193static const struct dummy_model model_ca0106 = {
 194        .name = "ca0106",
 195        .formats = SNDRV_PCM_FMTBIT_S16_LE,
 196        .buffer_bytes_max = ((65536-64)*8),
 197        .period_bytes_max = (65536-64),
 198        .periods_min = 2,
 199        .periods_max = 8,
 200        .channels_min = 2,
 201        .channels_max = 2,
 202        .rates = SNDRV_PCM_RATE_48000|SNDRV_PCM_RATE_96000|SNDRV_PCM_RATE_192000,
 203        .rate_min = 48000,
 204        .rate_max = 192000,
 205};
 206
 207static const struct dummy_model *dummy_models[] = {
 208        &model_emu10k1,
 209        &model_rme9652,
 210        &model_ice1712,
 211        &model_uda1341,
 212        &model_ac97,
 213        &model_ca0106,
 214        NULL
 215};
 216
 217/*
 218 * system timer interface
 219 */
 220
 221struct dummy_systimer_pcm {
 222        /* ops must be the first item */
 223        const struct dummy_timer_ops *timer_ops;
 224        spinlock_t lock;
 225        struct timer_list timer;
 226        unsigned long base_time;
 227        unsigned int frac_pos;  /* fractional sample position (based HZ) */
 228        unsigned int frac_period_rest;
 229        unsigned int frac_buffer_size;  /* buffer_size * HZ */
 230        unsigned int frac_period_size;  /* period_size * HZ */
 231        unsigned int rate;
 232        int elapsed;
 233        struct snd_pcm_substream *substream;
 234};
 235
 236static void dummy_systimer_rearm(struct dummy_systimer_pcm *dpcm)
 237{
 238        mod_timer(&dpcm->timer, jiffies +
 239                DIV_ROUND_UP(dpcm->frac_period_rest, dpcm->rate));
 240}
 241
 242static void dummy_systimer_update(struct dummy_systimer_pcm *dpcm)
 243{
 244        unsigned long delta;
 245
 246        delta = jiffies - dpcm->base_time;
 247        if (!delta)
 248                return;
 249        dpcm->base_time += delta;
 250        delta *= dpcm->rate;
 251        dpcm->frac_pos += delta;
 252        while (dpcm->frac_pos >= dpcm->frac_buffer_size)
 253                dpcm->frac_pos -= dpcm->frac_buffer_size;
 254        while (dpcm->frac_period_rest <= delta) {
 255                dpcm->elapsed++;
 256                dpcm->frac_period_rest += dpcm->frac_period_size;
 257        }
 258        dpcm->frac_period_rest -= delta;
 259}
 260
 261static int dummy_systimer_start(struct snd_pcm_substream *substream)
 262{
 263        struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 264        spin_lock(&dpcm->lock);
 265        dpcm->base_time = jiffies;
 266        dummy_systimer_rearm(dpcm);
 267        spin_unlock(&dpcm->lock);
 268        return 0;
 269}
 270
 271static int dummy_systimer_stop(struct snd_pcm_substream *substream)
 272{
 273        struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 274        spin_lock(&dpcm->lock);
 275        del_timer(&dpcm->timer);
 276        spin_unlock(&dpcm->lock);
 277        return 0;
 278}
 279
 280static int dummy_systimer_prepare(struct snd_pcm_substream *substream)
 281{
 282        struct snd_pcm_runtime *runtime = substream->runtime;
 283        struct dummy_systimer_pcm *dpcm = runtime->private_data;
 284
 285        dpcm->frac_pos = 0;
 286        dpcm->rate = runtime->rate;
 287        dpcm->frac_buffer_size = runtime->buffer_size * HZ;
 288        dpcm->frac_period_size = runtime->period_size * HZ;
 289        dpcm->frac_period_rest = dpcm->frac_period_size;
 290        dpcm->elapsed = 0;
 291
 292        return 0;
 293}
 294
 295static void dummy_systimer_callback(struct timer_list *t)
 296{
 297        struct dummy_systimer_pcm *dpcm = from_timer(dpcm, t, timer);
 298        unsigned long flags;
 299        int elapsed = 0;
 300        
 301        spin_lock_irqsave(&dpcm->lock, flags);
 302        dummy_systimer_update(dpcm);
 303        dummy_systimer_rearm(dpcm);
 304        elapsed = dpcm->elapsed;
 305        dpcm->elapsed = 0;
 306        spin_unlock_irqrestore(&dpcm->lock, flags);
 307        if (elapsed)
 308                snd_pcm_period_elapsed(dpcm->substream);
 309}
 310
 311static snd_pcm_uframes_t
 312dummy_systimer_pointer(struct snd_pcm_substream *substream)
 313{
 314        struct dummy_systimer_pcm *dpcm = substream->runtime->private_data;
 315        snd_pcm_uframes_t pos;
 316
 317        spin_lock(&dpcm->lock);
 318        dummy_systimer_update(dpcm);
 319        pos = dpcm->frac_pos / HZ;
 320        spin_unlock(&dpcm->lock);
 321        return pos;
 322}
 323
 324static int dummy_systimer_create(struct snd_pcm_substream *substream)
 325{
 326        struct dummy_systimer_pcm *dpcm;
 327
 328        dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 329        if (!dpcm)
 330                return -ENOMEM;
 331        substream->runtime->private_data = dpcm;
 332        timer_setup(&dpcm->timer, dummy_systimer_callback, 0);
 333        spin_lock_init(&dpcm->lock);
 334        dpcm->substream = substream;
 335        return 0;
 336}
 337
 338static void dummy_systimer_free(struct snd_pcm_substream *substream)
 339{
 340        kfree(substream->runtime->private_data);
 341}
 342
 343static const struct dummy_timer_ops dummy_systimer_ops = {
 344        .create =       dummy_systimer_create,
 345        .free =         dummy_systimer_free,
 346        .prepare =      dummy_systimer_prepare,
 347        .start =        dummy_systimer_start,
 348        .stop =         dummy_systimer_stop,
 349        .pointer =      dummy_systimer_pointer,
 350};
 351
 352#ifdef CONFIG_HIGH_RES_TIMERS
 353/*
 354 * hrtimer interface
 355 */
 356
 357struct dummy_hrtimer_pcm {
 358        /* ops must be the first item */
 359        const struct dummy_timer_ops *timer_ops;
 360        ktime_t base_time;
 361        ktime_t period_time;
 362        atomic_t running;
 363        struct hrtimer timer;
 364        struct snd_pcm_substream *substream;
 365};
 366
 367static enum hrtimer_restart dummy_hrtimer_callback(struct hrtimer *timer)
 368{
 369        struct dummy_hrtimer_pcm *dpcm;
 370
 371        dpcm = container_of(timer, struct dummy_hrtimer_pcm, timer);
 372        if (!atomic_read(&dpcm->running))
 373                return HRTIMER_NORESTART;
 374        /*
 375         * In cases of XRUN and draining, this calls .trigger to stop PCM
 376         * substream.
 377         */
 378        snd_pcm_period_elapsed(dpcm->substream);
 379        if (!atomic_read(&dpcm->running))
 380                return HRTIMER_NORESTART;
 381
 382        hrtimer_forward_now(timer, dpcm->period_time);
 383        return HRTIMER_RESTART;
 384}
 385
 386static int dummy_hrtimer_start(struct snd_pcm_substream *substream)
 387{
 388        struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 389
 390        dpcm->base_time = hrtimer_cb_get_time(&dpcm->timer);
 391        hrtimer_start(&dpcm->timer, dpcm->period_time, HRTIMER_MODE_REL_SOFT);
 392        atomic_set(&dpcm->running, 1);
 393        return 0;
 394}
 395
 396static int dummy_hrtimer_stop(struct snd_pcm_substream *substream)
 397{
 398        struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 399
 400        atomic_set(&dpcm->running, 0);
 401        if (!hrtimer_callback_running(&dpcm->timer))
 402                hrtimer_cancel(&dpcm->timer);
 403        return 0;
 404}
 405
 406static inline void dummy_hrtimer_sync(struct dummy_hrtimer_pcm *dpcm)
 407{
 408        hrtimer_cancel(&dpcm->timer);
 409}
 410
 411static snd_pcm_uframes_t
 412dummy_hrtimer_pointer(struct snd_pcm_substream *substream)
 413{
 414        struct snd_pcm_runtime *runtime = substream->runtime;
 415        struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 416        u64 delta;
 417        u32 pos;
 418
 419        delta = ktime_us_delta(hrtimer_cb_get_time(&dpcm->timer),
 420                               dpcm->base_time);
 421        delta = div_u64(delta * runtime->rate + 999999, 1000000);
 422        div_u64_rem(delta, runtime->buffer_size, &pos);
 423        return pos;
 424}
 425
 426static int dummy_hrtimer_prepare(struct snd_pcm_substream *substream)
 427{
 428        struct snd_pcm_runtime *runtime = substream->runtime;
 429        struct dummy_hrtimer_pcm *dpcm = runtime->private_data;
 430        unsigned int period, rate;
 431        long sec;
 432        unsigned long nsecs;
 433
 434        dummy_hrtimer_sync(dpcm);
 435        period = runtime->period_size;
 436        rate = runtime->rate;
 437        sec = period / rate;
 438        period %= rate;
 439        nsecs = div_u64((u64)period * 1000000000UL + rate - 1, rate);
 440        dpcm->period_time = ktime_set(sec, nsecs);
 441
 442        return 0;
 443}
 444
 445static int dummy_hrtimer_create(struct snd_pcm_substream *substream)
 446{
 447        struct dummy_hrtimer_pcm *dpcm;
 448
 449        dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 450        if (!dpcm)
 451                return -ENOMEM;
 452        substream->runtime->private_data = dpcm;
 453        hrtimer_init(&dpcm->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
 454        dpcm->timer.function = dummy_hrtimer_callback;
 455        dpcm->substream = substream;
 456        atomic_set(&dpcm->running, 0);
 457        return 0;
 458}
 459
 460static void dummy_hrtimer_free(struct snd_pcm_substream *substream)
 461{
 462        struct dummy_hrtimer_pcm *dpcm = substream->runtime->private_data;
 463        dummy_hrtimer_sync(dpcm);
 464        kfree(dpcm);
 465}
 466
 467static const struct dummy_timer_ops dummy_hrtimer_ops = {
 468        .create =       dummy_hrtimer_create,
 469        .free =         dummy_hrtimer_free,
 470        .prepare =      dummy_hrtimer_prepare,
 471        .start =        dummy_hrtimer_start,
 472        .stop =         dummy_hrtimer_stop,
 473        .pointer =      dummy_hrtimer_pointer,
 474};
 475
 476#endif /* CONFIG_HIGH_RES_TIMERS */
 477
 478/*
 479 * PCM interface
 480 */
 481
 482static int dummy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 483{
 484        switch (cmd) {
 485        case SNDRV_PCM_TRIGGER_START:
 486        case SNDRV_PCM_TRIGGER_RESUME:
 487                return get_dummy_ops(substream)->start(substream);
 488        case SNDRV_PCM_TRIGGER_STOP:
 489        case SNDRV_PCM_TRIGGER_SUSPEND:
 490                return get_dummy_ops(substream)->stop(substream);
 491        }
 492        return -EINVAL;
 493}
 494
 495static int dummy_pcm_prepare(struct snd_pcm_substream *substream)
 496{
 497        return get_dummy_ops(substream)->prepare(substream);
 498}
 499
 500static snd_pcm_uframes_t dummy_pcm_pointer(struct snd_pcm_substream *substream)
 501{
 502        return get_dummy_ops(substream)->pointer(substream);
 503}
 504
 505static const struct snd_pcm_hardware dummy_pcm_hardware = {
 506        .info =                 (SNDRV_PCM_INFO_MMAP |
 507                                 SNDRV_PCM_INFO_INTERLEAVED |
 508                                 SNDRV_PCM_INFO_RESUME |
 509                                 SNDRV_PCM_INFO_MMAP_VALID),
 510        .formats =              USE_FORMATS,
 511        .rates =                USE_RATE,
 512        .rate_min =             USE_RATE_MIN,
 513        .rate_max =             USE_RATE_MAX,
 514        .channels_min =         USE_CHANNELS_MIN,
 515        .channels_max =         USE_CHANNELS_MAX,
 516        .buffer_bytes_max =     MAX_BUFFER_SIZE,
 517        .period_bytes_min =     MIN_PERIOD_SIZE,
 518        .period_bytes_max =     MAX_PERIOD_SIZE,
 519        .periods_min =          USE_PERIODS_MIN,
 520        .periods_max =          USE_PERIODS_MAX,
 521        .fifo_size =            0,
 522};
 523
 524static int dummy_pcm_hw_params(struct snd_pcm_substream *substream,
 525                               struct snd_pcm_hw_params *hw_params)
 526{
 527        if (fake_buffer) {
 528                /* runtime->dma_bytes has to be set manually to allow mmap */
 529                substream->runtime->dma_bytes = params_buffer_bytes(hw_params);
 530                return 0;
 531        }
 532        return 0;
 533}
 534
 535static int dummy_pcm_open(struct snd_pcm_substream *substream)
 536{
 537        struct snd_dummy *dummy = snd_pcm_substream_chip(substream);
 538        const struct dummy_model *model = dummy->model;
 539        struct snd_pcm_runtime *runtime = substream->runtime;
 540        const struct dummy_timer_ops *ops;
 541        int err;
 542
 543        ops = &dummy_systimer_ops;
 544#ifdef CONFIG_HIGH_RES_TIMERS
 545        if (hrtimer)
 546                ops = &dummy_hrtimer_ops;
 547#endif
 548
 549        err = ops->create(substream);
 550        if (err < 0)
 551                return err;
 552        get_dummy_ops(substream) = ops;
 553
 554        runtime->hw = dummy->pcm_hw;
 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 (model == NULL)
 564                return 0;
 565
 566        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 567                if (model->playback_constraints)
 568                        err = model->playback_constraints(substream->runtime);
 569        } else {
 570                if (model->capture_constraints)
 571                        err = model->capture_constraints(substream->runtime);
 572        }
 573        if (err < 0) {
 574                get_dummy_ops(substream)->free(substream);
 575                return err;
 576        }
 577        return 0;
 578}
 579
 580static int dummy_pcm_close(struct snd_pcm_substream *substream)
 581{
 582        get_dummy_ops(substream)->free(substream);
 583        return 0;
 584}
 585
 586/*
 587 * dummy buffer handling
 588 */
 589
 590static void *dummy_page[2];
 591
 592static void free_fake_buffer(void)
 593{
 594        if (fake_buffer) {
 595                int i;
 596                for (i = 0; i < 2; i++)
 597                        if (dummy_page[i]) {
 598                                free_page((unsigned long)dummy_page[i]);
 599                                dummy_page[i] = NULL;
 600                        }
 601        }
 602}
 603
 604static int alloc_fake_buffer(void)
 605{
 606        int i;
 607
 608        if (!fake_buffer)
 609                return 0;
 610        for (i = 0; i < 2; i++) {
 611                dummy_page[i] = (void *)get_zeroed_page(GFP_KERNEL);
 612                if (!dummy_page[i]) {
 613                        free_fake_buffer();
 614                        return -ENOMEM;
 615                }
 616        }
 617        return 0;
 618}
 619
 620static int dummy_pcm_copy(struct snd_pcm_substream *substream,
 621                          int channel, unsigned long pos,
 622                          void __user *dst, unsigned long bytes)
 623{
 624        return 0; /* do nothing */
 625}
 626
 627static int dummy_pcm_copy_kernel(struct snd_pcm_substream *substream,
 628                                 int channel, unsigned long pos,
 629                                 void *dst, unsigned long bytes)
 630{
 631        return 0; /* do nothing */
 632}
 633
 634static int dummy_pcm_silence(struct snd_pcm_substream *substream,
 635                             int channel, unsigned long pos,
 636                             unsigned long bytes)
 637{
 638        return 0; /* do nothing */
 639}
 640
 641static struct page *dummy_pcm_page(struct snd_pcm_substream *substream,
 642                                   unsigned long offset)
 643{
 644        return virt_to_page(dummy_page[substream->stream]); /* the same page */
 645}
 646
 647static const struct snd_pcm_ops dummy_pcm_ops = {
 648        .open =         dummy_pcm_open,
 649        .close =        dummy_pcm_close,
 650        .hw_params =    dummy_pcm_hw_params,
 651        .prepare =      dummy_pcm_prepare,
 652        .trigger =      dummy_pcm_trigger,
 653        .pointer =      dummy_pcm_pointer,
 654};
 655
 656static const struct snd_pcm_ops dummy_pcm_ops_no_buf = {
 657        .open =         dummy_pcm_open,
 658        .close =        dummy_pcm_close,
 659        .hw_params =    dummy_pcm_hw_params,
 660        .prepare =      dummy_pcm_prepare,
 661        .trigger =      dummy_pcm_trigger,
 662        .pointer =      dummy_pcm_pointer,
 663        .copy_user =    dummy_pcm_copy,
 664        .copy_kernel =  dummy_pcm_copy_kernel,
 665        .fill_silence = dummy_pcm_silence,
 666        .page =         dummy_pcm_page,
 667};
 668
 669static int snd_card_dummy_pcm(struct snd_dummy *dummy, int device,
 670                              int substreams)
 671{
 672        struct snd_pcm *pcm;
 673        const struct snd_pcm_ops *ops;
 674        int err;
 675
 676        err = snd_pcm_new(dummy->card, "Dummy PCM", device,
 677                               substreams, substreams, &pcm);
 678        if (err < 0)
 679                return err;
 680        dummy->pcm = pcm;
 681        if (fake_buffer)
 682                ops = &dummy_pcm_ops_no_buf;
 683        else
 684                ops = &dummy_pcm_ops;
 685        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, ops);
 686        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, ops);
 687        pcm->private_data = dummy;
 688        pcm->info_flags = 0;
 689        strcpy(pcm->name, "Dummy PCM");
 690        if (!fake_buffer) {
 691                snd_pcm_set_managed_buffer_all(pcm,
 692                        SNDRV_DMA_TYPE_CONTINUOUS,
 693                        NULL,
 694                        0, 64*1024);
 695        }
 696        return 0;
 697}
 698
 699/*
 700 * mixer interface
 701 */
 702
 703#define DUMMY_VOLUME(xname, xindex, addr) \
 704{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
 705  .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ, \
 706  .name = xname, .index = xindex, \
 707  .info = snd_dummy_volume_info, \
 708  .get = snd_dummy_volume_get, .put = snd_dummy_volume_put, \
 709  .private_value = addr, \
 710  .tlv = { .p = db_scale_dummy } }
 711
 712static int snd_dummy_volume_info(struct snd_kcontrol *kcontrol,
 713                                 struct snd_ctl_elem_info *uinfo)
 714{
 715        uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 716        uinfo->count = 2;
 717        uinfo->value.integer.min = -50;
 718        uinfo->value.integer.max = 100;
 719        return 0;
 720}
 721 
 722static int snd_dummy_volume_get(struct snd_kcontrol *kcontrol,
 723                                struct snd_ctl_elem_value *ucontrol)
 724{
 725        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 726        int addr = kcontrol->private_value;
 727
 728        spin_lock_irq(&dummy->mixer_lock);
 729        ucontrol->value.integer.value[0] = dummy->mixer_volume[addr][0];
 730        ucontrol->value.integer.value[1] = dummy->mixer_volume[addr][1];
 731        spin_unlock_irq(&dummy->mixer_lock);
 732        return 0;
 733}
 734
 735static int snd_dummy_volume_put(struct snd_kcontrol *kcontrol,
 736                                struct snd_ctl_elem_value *ucontrol)
 737{
 738        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 739        int change, addr = kcontrol->private_value;
 740        int left, right;
 741
 742        left = ucontrol->value.integer.value[0];
 743        if (left < -50)
 744                left = -50;
 745        if (left > 100)
 746                left = 100;
 747        right = ucontrol->value.integer.value[1];
 748        if (right < -50)
 749                right = -50;
 750        if (right > 100)
 751                right = 100;
 752        spin_lock_irq(&dummy->mixer_lock);
 753        change = dummy->mixer_volume[addr][0] != left ||
 754                 dummy->mixer_volume[addr][1] != right;
 755        dummy->mixer_volume[addr][0] = left;
 756        dummy->mixer_volume[addr][1] = right;
 757        spin_unlock_irq(&dummy->mixer_lock);
 758        return change;
 759}
 760
 761static const DECLARE_TLV_DB_SCALE(db_scale_dummy, -4500, 30, 0);
 762
 763#define DUMMY_CAPSRC(xname, xindex, addr) \
 764{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
 765  .info = snd_dummy_capsrc_info, \
 766  .get = snd_dummy_capsrc_get, .put = snd_dummy_capsrc_put, \
 767  .private_value = addr }
 768
 769#define snd_dummy_capsrc_info   snd_ctl_boolean_stereo_info
 770 
 771static int snd_dummy_capsrc_get(struct snd_kcontrol *kcontrol,
 772                                struct snd_ctl_elem_value *ucontrol)
 773{
 774        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 775        int addr = kcontrol->private_value;
 776
 777        spin_lock_irq(&dummy->mixer_lock);
 778        ucontrol->value.integer.value[0] = dummy->capture_source[addr][0];
 779        ucontrol->value.integer.value[1] = dummy->capture_source[addr][1];
 780        spin_unlock_irq(&dummy->mixer_lock);
 781        return 0;
 782}
 783
 784static int snd_dummy_capsrc_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
 785{
 786        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 787        int change, addr = kcontrol->private_value;
 788        int left, right;
 789
 790        left = ucontrol->value.integer.value[0] & 1;
 791        right = ucontrol->value.integer.value[1] & 1;
 792        spin_lock_irq(&dummy->mixer_lock);
 793        change = dummy->capture_source[addr][0] != left &&
 794                 dummy->capture_source[addr][1] != right;
 795        dummy->capture_source[addr][0] = left;
 796        dummy->capture_source[addr][1] = right;
 797        spin_unlock_irq(&dummy->mixer_lock);
 798        return change;
 799}
 800
 801static int snd_dummy_iobox_info(struct snd_kcontrol *kcontrol,
 802                                struct snd_ctl_elem_info *info)
 803{
 804        static const char *const names[] = { "None", "CD Player" };
 805
 806        return snd_ctl_enum_info(info, 1, 2, names);
 807}
 808
 809static int snd_dummy_iobox_get(struct snd_kcontrol *kcontrol,
 810                               struct snd_ctl_elem_value *value)
 811{
 812        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 813
 814        value->value.enumerated.item[0] = dummy->iobox;
 815        return 0;
 816}
 817
 818static int snd_dummy_iobox_put(struct snd_kcontrol *kcontrol,
 819                               struct snd_ctl_elem_value *value)
 820{
 821        struct snd_dummy *dummy = snd_kcontrol_chip(kcontrol);
 822        int changed;
 823
 824        if (value->value.enumerated.item[0] > 1)
 825                return -EINVAL;
 826
 827        changed = value->value.enumerated.item[0] != dummy->iobox;
 828        if (changed) {
 829                dummy->iobox = value->value.enumerated.item[0];
 830
 831                if (dummy->iobox) {
 832                        dummy->cd_volume_ctl->vd[0].access &=
 833                                ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 834                        dummy->cd_switch_ctl->vd[0].access &=
 835                                ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 836                } else {
 837                        dummy->cd_volume_ctl->vd[0].access |=
 838                                SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 839                        dummy->cd_switch_ctl->vd[0].access |=
 840                                SNDRV_CTL_ELEM_ACCESS_INACTIVE;
 841                }
 842
 843                snd_ctl_notify(dummy->card, SNDRV_CTL_EVENT_MASK_INFO,
 844                               &dummy->cd_volume_ctl->id);
 845                snd_ctl_notify(dummy->card, SNDRV_CTL_EVENT_MASK_INFO,
 846                               &dummy->cd_switch_ctl->id);
 847        }
 848
 849        return changed;
 850}
 851
 852static const struct snd_kcontrol_new snd_dummy_controls[] = {
 853DUMMY_VOLUME("Master Volume", 0, MIXER_ADDR_MASTER),
 854DUMMY_CAPSRC("Master Capture Switch", 0, MIXER_ADDR_MASTER),
 855DUMMY_VOLUME("Synth Volume", 0, MIXER_ADDR_SYNTH),
 856DUMMY_CAPSRC("Synth Capture Switch", 0, MIXER_ADDR_SYNTH),
 857DUMMY_VOLUME("Line Volume", 0, MIXER_ADDR_LINE),
 858DUMMY_CAPSRC("Line Capture Switch", 0, MIXER_ADDR_LINE),
 859DUMMY_VOLUME("Mic Volume", 0, MIXER_ADDR_MIC),
 860DUMMY_CAPSRC("Mic Capture Switch", 0, MIXER_ADDR_MIC),
 861DUMMY_VOLUME("CD Volume", 0, MIXER_ADDR_CD),
 862DUMMY_CAPSRC("CD Capture Switch", 0, MIXER_ADDR_CD),
 863{
 864        .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 865        .name  = "External I/O Box",
 866        .info  = snd_dummy_iobox_info,
 867        .get   = snd_dummy_iobox_get,
 868        .put   = snd_dummy_iobox_put,
 869},
 870};
 871
 872static int snd_card_dummy_new_mixer(struct snd_dummy *dummy)
 873{
 874        struct snd_card *card = dummy->card;
 875        struct snd_kcontrol *kcontrol;
 876        unsigned int idx;
 877        int err;
 878
 879        spin_lock_init(&dummy->mixer_lock);
 880        strcpy(card->mixername, "Dummy Mixer");
 881        dummy->iobox = 1;
 882
 883        for (idx = 0; idx < ARRAY_SIZE(snd_dummy_controls); idx++) {
 884                kcontrol = snd_ctl_new1(&snd_dummy_controls[idx], dummy);
 885                err = snd_ctl_add(card, kcontrol);
 886                if (err < 0)
 887                        return err;
 888                if (!strcmp(kcontrol->id.name, "CD Volume"))
 889                        dummy->cd_volume_ctl = kcontrol;
 890                else if (!strcmp(kcontrol->id.name, "CD Capture Switch"))
 891                        dummy->cd_switch_ctl = kcontrol;
 892
 893        }
 894        return 0;
 895}
 896
 897#if defined(CONFIG_SND_DEBUG) && defined(CONFIG_SND_PROC_FS)
 898/*
 899 * proc interface
 900 */
 901static void print_formats(struct snd_dummy *dummy,
 902                          struct snd_info_buffer *buffer)
 903{
 904        snd_pcm_format_t i;
 905
 906        pcm_for_each_format(i) {
 907                if (dummy->pcm_hw.formats & pcm_format_to_bits(i))
 908                        snd_iprintf(buffer, " %s", snd_pcm_format_name(i));
 909        }
 910}
 911
 912static void print_rates(struct snd_dummy *dummy,
 913                        struct snd_info_buffer *buffer)
 914{
 915        static const int rates[] = {
 916                5512, 8000, 11025, 16000, 22050, 32000, 44100, 48000,
 917                64000, 88200, 96000, 176400, 192000,
 918        };
 919        int i;
 920
 921        if (dummy->pcm_hw.rates & SNDRV_PCM_RATE_CONTINUOUS)
 922                snd_iprintf(buffer, " continuous");
 923        if (dummy->pcm_hw.rates & SNDRV_PCM_RATE_KNOT)
 924                snd_iprintf(buffer, " knot");
 925        for (i = 0; i < ARRAY_SIZE(rates); i++)
 926                if (dummy->pcm_hw.rates & (1 << i))
 927                        snd_iprintf(buffer, " %d", rates[i]);
 928}
 929
 930#define get_dummy_int_ptr(dummy, ofs) \
 931        (unsigned int *)((char *)&((dummy)->pcm_hw) + (ofs))
 932#define get_dummy_ll_ptr(dummy, ofs) \
 933        (unsigned long long *)((char *)&((dummy)->pcm_hw) + (ofs))
 934
 935struct dummy_hw_field {
 936        const char *name;
 937        const char *format;
 938        unsigned int offset;
 939        unsigned int size;
 940};
 941#define FIELD_ENTRY(item, fmt) {                   \
 942        .name = #item,                             \
 943        .format = fmt,                             \
 944        .offset = offsetof(struct snd_pcm_hardware, item), \
 945        .size = sizeof(dummy_pcm_hardware.item) }
 946
 947static const struct dummy_hw_field fields[] = {
 948        FIELD_ENTRY(formats, "%#llx"),
 949        FIELD_ENTRY(rates, "%#x"),
 950        FIELD_ENTRY(rate_min, "%d"),
 951        FIELD_ENTRY(rate_max, "%d"),
 952        FIELD_ENTRY(channels_min, "%d"),
 953        FIELD_ENTRY(channels_max, "%d"),
 954        FIELD_ENTRY(buffer_bytes_max, "%ld"),
 955        FIELD_ENTRY(period_bytes_min, "%ld"),
 956        FIELD_ENTRY(period_bytes_max, "%ld"),
 957        FIELD_ENTRY(periods_min, "%d"),
 958        FIELD_ENTRY(periods_max, "%d"),
 959};
 960
 961static void dummy_proc_read(struct snd_info_entry *entry,
 962                            struct snd_info_buffer *buffer)
 963{
 964        struct snd_dummy *dummy = entry->private_data;
 965        int i;
 966
 967        for (i = 0; i < ARRAY_SIZE(fields); i++) {
 968                snd_iprintf(buffer, "%s ", fields[i].name);
 969                if (fields[i].size == sizeof(int))
 970                        snd_iprintf(buffer, fields[i].format,
 971                                *get_dummy_int_ptr(dummy, fields[i].offset));
 972                else
 973                        snd_iprintf(buffer, fields[i].format,
 974                                *get_dummy_ll_ptr(dummy, fields[i].offset));
 975                if (!strcmp(fields[i].name, "formats"))
 976                        print_formats(dummy, buffer);
 977                else if (!strcmp(fields[i].name, "rates"))
 978                        print_rates(dummy, buffer);
 979                snd_iprintf(buffer, "\n");
 980        }
 981}
 982
 983static void dummy_proc_write(struct snd_info_entry *entry,
 984                             struct snd_info_buffer *buffer)
 985{
 986        struct snd_dummy *dummy = entry->private_data;
 987        char line[64];
 988
 989        while (!snd_info_get_line(buffer, line, sizeof(line))) {
 990                char item[20];
 991                const char *ptr;
 992                unsigned long long val;
 993                int i;
 994
 995                ptr = snd_info_get_str(item, line, sizeof(item));
 996                for (i = 0; i < ARRAY_SIZE(fields); i++) {
 997                        if (!strcmp(item, fields[i].name))
 998                                break;
 999                }
1000                if (i >= ARRAY_SIZE(fields))
1001                        continue;
1002                snd_info_get_str(item, ptr, sizeof(item));
1003                if (kstrtoull(item, 0, &val))
1004                        continue;
1005                if (fields[i].size == sizeof(int))
1006                        *get_dummy_int_ptr(dummy, fields[i].offset) = val;
1007                else
1008                        *get_dummy_ll_ptr(dummy, fields[i].offset) = val;
1009        }
1010}
1011
1012static void dummy_proc_init(struct snd_dummy *chip)
1013{
1014        snd_card_rw_proc_new(chip->card, "dummy_pcm", chip,
1015                             dummy_proc_read, dummy_proc_write);
1016}
1017#else
1018#define dummy_proc_init(x)
1019#endif /* CONFIG_SND_DEBUG && CONFIG_SND_PROC_FS */
1020
1021static int snd_dummy_probe(struct platform_device *devptr)
1022{
1023        struct snd_card *card;
1024        struct snd_dummy *dummy;
1025        const struct dummy_model *m = NULL, **mdl;
1026        int idx, err;
1027        int dev = devptr->id;
1028
1029        err = snd_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
1030                           sizeof(struct snd_dummy), &card);
1031        if (err < 0)
1032                return err;
1033        dummy = card->private_data;
1034        dummy->card = card;
1035        for (mdl = dummy_models; *mdl && model[dev]; mdl++) {
1036                if (strcmp(model[dev], (*mdl)->name) == 0) {
1037                        printk(KERN_INFO
1038                                "snd-dummy: Using model '%s' for card %i\n",
1039                                (*mdl)->name, card->number);
1040                        m = dummy->model = *mdl;
1041                        break;
1042                }
1043        }
1044        for (idx = 0; idx < MAX_PCM_DEVICES && idx < pcm_devs[dev]; idx++) {
1045                if (pcm_substreams[dev] < 1)
1046                        pcm_substreams[dev] = 1;
1047                if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
1048                        pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
1049                err = snd_card_dummy_pcm(dummy, idx, pcm_substreams[dev]);
1050                if (err < 0)
1051                        goto __nodev;
1052        }
1053
1054        dummy->pcm_hw = dummy_pcm_hardware;
1055        if (m) {
1056                if (m->formats)
1057                        dummy->pcm_hw.formats = m->formats;
1058                if (m->buffer_bytes_max)
1059                        dummy->pcm_hw.buffer_bytes_max = m->buffer_bytes_max;
1060                if (m->period_bytes_min)
1061                        dummy->pcm_hw.period_bytes_min = m->period_bytes_min;
1062                if (m->period_bytes_max)
1063                        dummy->pcm_hw.period_bytes_max = m->period_bytes_max;
1064                if (m->periods_min)
1065                        dummy->pcm_hw.periods_min = m->periods_min;
1066                if (m->periods_max)
1067                        dummy->pcm_hw.periods_max = m->periods_max;
1068                if (m->rates)
1069                        dummy->pcm_hw.rates = m->rates;
1070                if (m->rate_min)
1071                        dummy->pcm_hw.rate_min = m->rate_min;
1072                if (m->rate_max)
1073                        dummy->pcm_hw.rate_max = m->rate_max;
1074                if (m->channels_min)
1075                        dummy->pcm_hw.channels_min = m->channels_min;
1076                if (m->channels_max)
1077                        dummy->pcm_hw.channels_max = m->channels_max;
1078        }
1079
1080        err = snd_card_dummy_new_mixer(dummy);
1081        if (err < 0)
1082                goto __nodev;
1083        strcpy(card->driver, "Dummy");
1084        strcpy(card->shortname, "Dummy");
1085        sprintf(card->longname, "Dummy %i", dev + 1);
1086
1087        dummy_proc_init(dummy);
1088
1089        err = snd_card_register(card);
1090        if (err == 0) {
1091                platform_set_drvdata(devptr, card);
1092                return 0;
1093        }
1094      __nodev:
1095        snd_card_free(card);
1096        return err;
1097}
1098
1099static int snd_dummy_remove(struct platform_device *devptr)
1100{
1101        snd_card_free(platform_get_drvdata(devptr));
1102        return 0;
1103}
1104
1105#ifdef CONFIG_PM_SLEEP
1106static int snd_dummy_suspend(struct device *pdev)
1107{
1108        struct snd_card *card = dev_get_drvdata(pdev);
1109
1110        snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
1111        return 0;
1112}
1113        
1114static int snd_dummy_resume(struct device *pdev)
1115{
1116        struct snd_card *card = dev_get_drvdata(pdev);
1117
1118        snd_power_change_state(card, SNDRV_CTL_POWER_D0);
1119        return 0;
1120}
1121
1122static SIMPLE_DEV_PM_OPS(snd_dummy_pm, snd_dummy_suspend, snd_dummy_resume);
1123#define SND_DUMMY_PM_OPS        &snd_dummy_pm
1124#else
1125#define SND_DUMMY_PM_OPS        NULL
1126#endif
1127
1128#define SND_DUMMY_DRIVER        "snd_dummy"
1129
1130static struct platform_driver snd_dummy_driver = {
1131        .probe          = snd_dummy_probe,
1132        .remove         = snd_dummy_remove,
1133        .driver         = {
1134                .name   = SND_DUMMY_DRIVER,
1135                .pm     = SND_DUMMY_PM_OPS,
1136        },
1137};
1138
1139static void snd_dummy_unregister_all(void)
1140{
1141        int i;
1142
1143        for (i = 0; i < ARRAY_SIZE(devices); ++i)
1144                platform_device_unregister(devices[i]);
1145        platform_driver_unregister(&snd_dummy_driver);
1146        free_fake_buffer();
1147}
1148
1149static int __init alsa_card_dummy_init(void)
1150{
1151        int i, cards, err;
1152
1153        err = platform_driver_register(&snd_dummy_driver);
1154        if (err < 0)
1155                return err;
1156
1157        err = alloc_fake_buffer();
1158        if (err < 0) {
1159                platform_driver_unregister(&snd_dummy_driver);
1160                return err;
1161        }
1162
1163        cards = 0;
1164        for (i = 0; i < SNDRV_CARDS; i++) {
1165                struct platform_device *device;
1166                if (! enable[i])
1167                        continue;
1168                device = platform_device_register_simple(SND_DUMMY_DRIVER,
1169                                                         i, NULL, 0);
1170                if (IS_ERR(device))
1171                        continue;
1172                if (!platform_get_drvdata(device)) {
1173                        platform_device_unregister(device);
1174                        continue;
1175                }
1176                devices[i] = device;
1177                cards++;
1178        }
1179        if (!cards) {
1180#ifdef MODULE
1181                printk(KERN_ERR "Dummy soundcard not found or device busy\n");
1182#endif
1183                snd_dummy_unregister_all();
1184                return -ENODEV;
1185        }
1186        return 0;
1187}
1188
1189static void __exit alsa_card_dummy_exit(void)
1190{
1191        snd_dummy_unregister_all();
1192}
1193
1194module_init(alsa_card_dummy_init)
1195module_exit(alsa_card_dummy_exit)
1196