audio/paaudio.c

   1 /* public domain */
   2
   3 #include "qemu/osdep.h"
   4 #include "qemu/module.h"
   5 #include "audio.h"
   6 #include "qapi/opts-visitor.h"
   7
   8 #include <pulse/pulseaudio.h>
   9
  10 #define AUDIO_CAP "pulseaudio"
  11 #include "audio_int.h"
  12
  13 typedef struct PAConnection {
  14     char *server;
  15     int refcount;
  16     QTAILQ_ENTRY(PAConnection) list;
  17
  18     pa_threaded_mainloop *mainloop;
  19     pa_context *context;
  20 } PAConnection;
  21
  22 static QTAILQ_HEAD(PAConnectionHead, PAConnection) pa_conns =
  23     QTAILQ_HEAD_INITIALIZER(pa_conns);
  24
  25 typedef struct {
  26     Audiodev *dev;
  27     PAConnection *conn;
  28 } paaudio;
  29
  30 typedef struct {
  31     HWVoiceOut hw;
  32     pa_stream *stream;
  33     paaudio *g;
  34     size_t samples;
  35 } PAVoiceOut;
  36
  37 typedef struct {
  38     HWVoiceIn hw;
  39     pa_stream *stream;
  40     const void *read_data;
  41     size_t read_length;
  42     paaudio *g;
  43     size_t samples;
  44 } PAVoiceIn;
  45
  46 static void qpa_conn_fini(PAConnection *c);
  47
  48 static void GCC_FMT_ATTR (2, 3) qpa_logerr (int err, const char *fmt, ...)
  49 {
  50     va_list ap;
  51
  52     va_start (ap, fmt);
  53     AUD_vlog (AUDIO_CAP, fmt, ap);
  54     va_end (ap);
  55
  56     AUD_log (AUDIO_CAP, "Reason: %s\n", pa_strerror (err));
  57 }
  58
  59 #ifndef PA_CONTEXT_IS_GOOD
  60 static inline int PA_CONTEXT_IS_GOOD(pa_context_state_t x)
  61 {
  62     return
  63         x == PA_CONTEXT_CONNECTING ||
  64         x == PA_CONTEXT_AUTHORIZING ||
  65         x == PA_CONTEXT_SETTING_NAME ||
  66         x == PA_CONTEXT_READY;
  67 }
  68 #endif
  69
  70 #ifndef PA_STREAM_IS_GOOD
  71 static inline int PA_STREAM_IS_GOOD(pa_stream_state_t x)
  72 {
  73     return
  74         x == PA_STREAM_CREATING ||
  75         x == PA_STREAM_READY;
  76 }
  77 #endif
  78
  79 #define CHECK_SUCCESS_GOTO(c, expression, label, msg)           \
  80     do {                                                        \
  81         if (!(expression)) {                                    \
  82             qpa_logerr(pa_context_errno((c)->context), msg);    \
  83             goto label;                                         \
  84         }                                                       \
  85     } while (0)
  86
  87 #define CHECK_DEAD_GOTO(c, stream, label, msg)                          \
  88     do {                                                                \
  89         if (!(c)->context || !PA_CONTEXT_IS_GOOD (pa_context_get_state((c)->context)) || \
  90             !(stream) || !PA_STREAM_IS_GOOD (pa_stream_get_state ((stream)))) { \
  91             if (((c)->context && pa_context_get_state ((c)->context) == PA_CONTEXT_FAILED) || \
  92                 ((stream) && pa_stream_get_state ((stream)) == PA_STREAM_FAILED)) { \
  93                 qpa_logerr(pa_context_errno((c)->context), msg);        \
  94             } else {                                                    \
  95                 qpa_logerr(PA_ERR_BADSTATE, msg);                       \
  96             }                                                           \
  97             goto label;                                                 \
  98         }                                                               \
  99     } while (0)
 100
 101 static size_t qpa_read(HWVoiceIn *hw, void *data, size_t length)
 102 {
 103     PAVoiceIn *p = (PAVoiceIn *) hw;
 104     PAConnection *c = p->g->conn;
 105     size_t l;
 106     int r;
 107
 108     pa_threaded_mainloop_lock(c->mainloop);
 109
 110     CHECK_DEAD_GOTO(c, p->stream, unlock_and_fail,
 111                     "pa_threaded_mainloop_lock failed\n");
 112
 113     if (!p->read_length) {
 114         r = pa_stream_peek(p->stream, &p->read_data, &p->read_length);
 115         CHECK_SUCCESS_GOTO(c, r == 0, unlock_and_fail,
 116                            "pa_stream_peek failed\n");
 117     }
 118
 119     l = MIN(p->read_length, length);
 120     memcpy(data, p->read_data, l);
 121
 122     p->read_data += l;
 123     p->read_length -= l;
 124
 125     if (!p->read_length) {
 126         r = pa_stream_drop(p->stream);
 127         CHECK_SUCCESS_GOTO(c, r == 0, unlock_and_fail,
 128                            "pa_stream_drop failed\n");
 129     }
 130
 131     pa_threaded_mainloop_unlock(c->mainloop);
 132     return l;
 133
 134 unlock_and_fail:
 135     pa_threaded_mainloop_unlock(c->mainloop);
 136     return 0;
 137 }
 138
 139 static size_t qpa_write(HWVoiceOut *hw, void *data, size_t length)
 140 {
 141     PAVoiceOut *p = (PAVoiceOut *) hw;
 142     PAConnection *c = p->g->conn;
 143     size_t l;
 144     int r;
 145
 146     pa_threaded_mainloop_lock(c->mainloop);
 147
 148     CHECK_DEAD_GOTO(c, p->stream, unlock_and_fail,
 149                     "pa_threaded_mainloop_lock failed\n");
 150
 151     l = pa_stream_writable_size(p->stream);
 152
 153     CHECK_SUCCESS_GOTO(c, l != (size_t) -1, unlock_and_fail,
 154                        "pa_stream_writable_size failed\n");
 155
 156     if (l > length) {
 157         l = length;
 158     }
 159
 160     r = pa_stream_write(p->stream, data, l, NULL, 0LL, PA_SEEK_RELATIVE);
 161     CHECK_SUCCESS_GOTO(c, r >= 0, unlock_and_fail, "pa_stream_write failed\n");
 162
 163     pa_threaded_mainloop_unlock(c->mainloop);
 164     return l;
 165
 166 unlock_and_fail:
 167     pa_threaded_mainloop_unlock(c->mainloop);
 168     return 0;
 169 }
 170
 171 static pa_sample_format_t audfmt_to_pa (AudioFormat afmt, int endianness)
 172 {
 173     int format;
 174
 175     switch (afmt) {
 176     case AUDIO_FORMAT_S8:
 177     case AUDIO_FORMAT_U8:
 178         format = PA_SAMPLE_U8;
 179         break;
 180     case AUDIO_FORMAT_S16:
 181     case AUDIO_FORMAT_U16:
 182         format = endianness ? PA_SAMPLE_S16BE : PA_SAMPLE_S16LE;
 183         break;
 184     case AUDIO_FORMAT_S32:
 185     case AUDIO_FORMAT_U32:
 186         format = endianness ? PA_SAMPLE_S32BE : PA_SAMPLE_S32LE;
 187         break;
 188     default:
 189         dolog ("Internal logic error: Bad audio format %d\n", afmt);
 190         format = PA_SAMPLE_U8;
 191         break;
 192     }
 193     return format;
 194 }
 195
 196 static AudioFormat pa_to_audfmt (pa_sample_format_t fmt, int *endianness)
 197 {
 198     switch (fmt) {
 199     case PA_SAMPLE_U8:
 200         return AUDIO_FORMAT_U8;
 201     case PA_SAMPLE_S16BE:
 202         *endianness = 1;
 203         return AUDIO_FORMAT_S16;
 204     case PA_SAMPLE_S16LE:
 205         *endianness = 0;
 206         return AUDIO_FORMAT_S16;
 207     case PA_SAMPLE_S32BE:
 208         *endianness = 1;
 209         return AUDIO_FORMAT_S32;
 210     case PA_SAMPLE_S32LE:
 211         *endianness = 0;
 212         return AUDIO_FORMAT_S32;
 213     default:
 214         dolog ("Internal logic error: Bad pa_sample_format %d\n", fmt);
 215         return AUDIO_FORMAT_U8;
 216     }
 217 }
 218
 219 static void context_state_cb (pa_context *c, void *userdata)
 220 {
 221     PAConnection *conn = userdata;
 222
 223     switch (pa_context_get_state(c)) {
 224     case PA_CONTEXT_READY:
 225     case PA_CONTEXT_TERMINATED:
 226     case PA_CONTEXT_FAILED:
 227         pa_threaded_mainloop_signal(conn->mainloop, 0);
 228         break;
 229
 230     case PA_CONTEXT_UNCONNECTED:
 231     case PA_CONTEXT_CONNECTING:
 232     case PA_CONTEXT_AUTHORIZING:
 233     case PA_CONTEXT_SETTING_NAME:
 234         break;
 235     }
 236 }
 237
 238 static void stream_state_cb (pa_stream *s, void * userdata)
 239 {
 240     PAConnection *c = userdata;
 241
 242     switch (pa_stream_get_state (s)) {
 243
 244     case PA_STREAM_READY:
 245     case PA_STREAM_FAILED:
 246     case PA_STREAM_TERMINATED:
 247         pa_threaded_mainloop_signal(c->mainloop, 0);
 248         break;
 249
 250     case PA_STREAM_UNCONNECTED:
 251     case PA_STREAM_CREATING:
 252         break;
 253     }
 254 }
 255
 256 static pa_stream *qpa_simple_new (
 257         PAConnection *c,
 258         const char *name,
 259         pa_stream_direction_t dir,
 260         const char *dev,
 261         const pa_sample_spec *ss,
 262         const pa_channel_map *map,
 263         const pa_buffer_attr *attr,
 264         int *rerror)
 265 {
 266     int r;
 267     pa_stream *stream;
 268     pa_stream_flags_t flags;
 269
 270     pa_threaded_mainloop_lock(c->mainloop);
 271
 272     stream = pa_stream_new(c->context, name, ss, map);
 273     if (!stream) {
 274         goto fail;
 275     }
 276
 277     pa_stream_set_state_callback(stream, stream_state_cb, c);
 278
 279     flags =
 280         PA_STREAM_INTERPOLATE_TIMING
 281         | PA_STREAM_AUTO_TIMING_UPDATE
 282         | PA_STREAM_EARLY_REQUESTS;
 283
 284     if (dev) {
 285         /* don't move the stream if the user specified a sink/source */
 286         flags |= PA_STREAM_DONT_MOVE;
 287     }
 288
 289     if (dir == PA_STREAM_PLAYBACK) {
 290         r = pa_stream_connect_playback(stream, dev, attr, flags, NULL, NULL);
 291     } else {
 292         r = pa_stream_connect_record(stream, dev, attr, flags);
 293     }
 294
 295     if (r < 0) {
 296       goto fail;
 297     }
 298
 299     pa_threaded_mainloop_unlock(c->mainloop);
 300
 301     return stream;
 302
 303 fail:
 304     pa_threaded_mainloop_unlock(c->mainloop);
 305
 306     if (stream) {
 307         pa_stream_unref (stream);
 308     }
 309
 310     *rerror = pa_context_errno(c->context);
 311
 312     return NULL;
 313 }
 314
 315 static int qpa_init_out(HWVoiceOut *hw, struct audsettings *as,
 316                         void *drv_opaque)
 317 {
 318     int error;
 319     pa_sample_spec ss;
 320     pa_buffer_attr ba;
 321     struct audsettings obt_as = *as;
 322     PAVoiceOut *pa = (PAVoiceOut *) hw;
 323     paaudio *g = pa->g = drv_opaque;
 324     AudiodevPaOptions *popts = &g->dev->u.pa;
 325     AudiodevPaPerDirectionOptions *ppdo = popts->out;
 326     PAConnection *c = g->conn;
 327
 328     ss.format = audfmt_to_pa (as->fmt, as->endianness);
 329     ss.channels = as->nchannels;
 330     ss.rate = as->freq;
 331
 332     ba.tlength = pa_usec_to_bytes(ppdo->latency, &ss);
 333     ba.minreq = -1;
 334     ba.maxlength = -1;
 335     ba.prebuf = -1;
 336
 337     obt_as.fmt = pa_to_audfmt (ss.format, &obt_as.endianness);
 338
 339     pa->stream = qpa_simple_new (
 340         c,
 341         "qemu",
 342         PA_STREAM_PLAYBACK,
 343         ppdo->has_name ? ppdo->name : NULL,
 344         &ss,
 345         NULL,                   /* channel map */
 346         &ba,                    /* buffering attributes */
 347         &error
 348         );
 349     if (!pa->stream) {
 350         qpa_logerr (error, "pa_simple_new for playback failed\n");
 351         goto fail1;
 352     }
 353
 354     audio_pcm_init_info (&hw->info, &obt_as);
 355     hw->samples = pa->samples = audio_buffer_samples(
 356         qapi_AudiodevPaPerDirectionOptions_base(ppdo),
 357         &obt_as, ppdo->buffer_length);
 358
 359     return 0;
 360
 361  fail1:
 362     return -1;
 363 }
 364
 365 static int qpa_init_in(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque)
 366 {
 367     int error;
 368     pa_sample_spec ss;
 369     pa_buffer_attr ba;
 370     struct audsettings obt_as = *as;
 371     PAVoiceIn *pa = (PAVoiceIn *) hw;
 372     paaudio *g = pa->g = drv_opaque;
 373     AudiodevPaOptions *popts = &g->dev->u.pa;
 374     AudiodevPaPerDirectionOptions *ppdo = popts->in;
 375     PAConnection *c = g->conn;
 376
 377     ss.format = audfmt_to_pa (as->fmt, as->endianness);
 378     ss.channels = as->nchannels;
 379     ss.rate = as->freq;
 380
 381     ba.fragsize = pa_usec_to_bytes(ppdo->latency, &ss);
 382     ba.maxlength = pa_usec_to_bytes(ppdo->latency * 2, &ss);
 383     ba.minreq = -1;
 384     ba.prebuf = -1;
 385
 386     obt_as.fmt = pa_to_audfmt (ss.format, &obt_as.endianness);
 387
 388     pa->stream = qpa_simple_new (
 389         c,
 390         "qemu",
 391         PA_STREAM_RECORD,
 392         ppdo->has_name ? ppdo->name : NULL,
 393         &ss,
 394         NULL,                   /* channel map */
 395         &ba,                    /* buffering attributes */
 396         &error
 397         );
 398     if (!pa->stream) {
 399         qpa_logerr (error, "pa_simple_new for capture failed\n");
 400         goto fail1;
 401     }
 402
 403     audio_pcm_init_info (&hw->info, &obt_as);
 404     hw->samples = pa->samples = audio_buffer_samples(
 405         qapi_AudiodevPaPerDirectionOptions_base(ppdo),
 406         &obt_as, ppdo->buffer_length);
 407
 408     return 0;
 409
 410  fail1:
 411     return -1;
 412 }
 413
 414 static void qpa_simple_disconnect(PAConnection *c, pa_stream *stream)
 415 {
 416     int err;
 417
 418     pa_threaded_mainloop_lock(c->mainloop);
 419     /*
 420      * wait until actually connects. workaround pa bug #247
 421      * https://gitlab.freedesktop.org/pulseaudio/pulseaudio/issues/247
 422      */
 423     while (pa_stream_get_state(stream) == PA_STREAM_CREATING) {
 424         pa_threaded_mainloop_wait(c->mainloop);
 425     }
 426
 427     err = pa_stream_disconnect(stream);
 428     if (err != 0) {
 429         dolog("Failed to disconnect! err=%d\n", err);
 430     }
 431     pa_stream_unref(stream);
 432     pa_threaded_mainloop_unlock(c->mainloop);
 433 }
 434
 435 static void qpa_fini_out (HWVoiceOut *hw)
 436 {
 437     PAVoiceOut *pa = (PAVoiceOut *) hw;
 438
 439     if (pa->stream) {
 440         qpa_simple_disconnect(pa->g->conn, pa->stream);
 441         pa->stream = NULL;
 442     }
 443 }
 444
 445 static void qpa_fini_in (HWVoiceIn *hw)
 446 {
 447     PAVoiceIn *pa = (PAVoiceIn *) hw;
 448
 449     if (pa->stream) {
 450         qpa_simple_disconnect(pa->g->conn, pa->stream);
 451         pa->stream = NULL;
 452     }
 453 }
 454
 455 static void qpa_volume_out(HWVoiceOut *hw, struct mixeng_volume *vol)
 456 {
 457     PAVoiceOut *pa = (PAVoiceOut *) hw;
 458     pa_operation *op;
 459     pa_cvolume v;
 460     PAConnection *c = pa->g->conn;
 461
 462 #ifdef PA_CHECK_VERSION    /* macro is present in 0.9.16+ */
 463     pa_cvolume_init (&v);  /* function is present in 0.9.13+ */
 464 #endif
 465
 466     v.channels = 2;
 467     v.values[0] = ((PA_VOLUME_NORM - PA_VOLUME_MUTED) * vol->l) / UINT32_MAX;
 468     v.values[1] = ((PA_VOLUME_NORM - PA_VOLUME_MUTED) * vol->r) / UINT32_MAX;
 469
 470     pa_threaded_mainloop_lock(c->mainloop);
 471
 472     op = pa_context_set_sink_input_volume(c->context,
 473                                           pa_stream_get_index(pa->stream),
 474                                           &v, NULL, NULL);
 475     if (!op) {
 476         qpa_logerr(pa_context_errno(c->context),
 477                    "set_sink_input_volume() failed\n");
 478     } else {
 479         pa_operation_unref(op);
 480     }
 481
 482     op = pa_context_set_sink_input_mute(c->context,
 483                                         pa_stream_get_index(pa->stream),
 484                                         vol->mute, NULL, NULL);
 485     if (!op) {
 486         qpa_logerr(pa_context_errno(c->context),
 487                    "set_sink_input_mute() failed\n");
 488     } else {
 489         pa_operation_unref(op);
 490     }
 491
 492     pa_threaded_mainloop_unlock(c->mainloop);
 493 }
 494
 495 static void qpa_volume_in(HWVoiceIn *hw, struct mixeng_volume *vol)
 496 {
 497     PAVoiceIn *pa = (PAVoiceIn *) hw;
 498     pa_operation *op;
 499     pa_cvolume v;
 500     PAConnection *c = pa->g->conn;
 501
 502 #ifdef PA_CHECK_VERSION
 503     pa_cvolume_init (&v);
 504 #endif
 505
 506     v.channels = 2;
 507     v.values[0] = ((PA_VOLUME_NORM - PA_VOLUME_MUTED) * vol->l) / UINT32_MAX;
 508     v.values[1] = ((PA_VOLUME_NORM - PA_VOLUME_MUTED) * vol->r) / UINT32_MAX;
 509
 510     pa_threaded_mainloop_lock(c->mainloop);
 511
 512     op = pa_context_set_source_output_volume(c->context,
 513         pa_stream_get_index(pa->stream),
 514         &v, NULL, NULL);
 515     if (!op) {
 516         qpa_logerr(pa_context_errno(c->context),
 517                    "set_source_output_volume() failed\n");
 518     } else {
 519         pa_operation_unref(op);
 520     }
 521
 522     op = pa_context_set_source_output_mute(c->context,
 523         pa_stream_get_index(pa->stream),
 524         vol->mute, NULL, NULL);
 525     if (!op) {
 526         qpa_logerr(pa_context_errno(c->context),
 527                    "set_source_output_mute() failed\n");
 528     } else {
 529         pa_operation_unref(op);
 530     }
 531
 532     pa_threaded_mainloop_unlock(c->mainloop);
 533 }
 534
 535 static int qpa_validate_per_direction_opts(Audiodev *dev,
 536                                            AudiodevPaPerDirectionOptions *pdo)
 537 {
 538     if (!pdo->has_buffer_length) {
 539         pdo->has_buffer_length = true;
 540         pdo->buffer_length = 46440;
 541     }
 542     if (!pdo->has_latency) {
 543         pdo->has_latency = true;
 544         pdo->latency = 15000;
 545     }
 546     return 1;
 547 }
 548
 549 /* common */
 550 static void *qpa_conn_init(const char *server)
 551 {
 552     PAConnection *c = g_malloc0(sizeof(PAConnection));
 553     QTAILQ_INSERT_TAIL(&pa_conns, c, list);
 554
 555     c->mainloop = pa_threaded_mainloop_new();
 556     if (!c->mainloop) {
 557         goto fail;
 558     }
 559
 560     c->context = pa_context_new(pa_threaded_mainloop_get_api(c->mainloop),
 561                                 server);
 562     if (!c->context) {
 563         goto fail;
 564     }
 565
 566     pa_context_set_state_callback(c->context, context_state_cb, c);
 567
 568     if (pa_context_connect(c->context, server, 0, NULL) < 0) {
 569         qpa_logerr(pa_context_errno(c->context),
 570                    "pa_context_connect() failed\n");
 571         goto fail;
 572     }
 573
 574     pa_threaded_mainloop_lock(c->mainloop);
 575
 576     if (pa_threaded_mainloop_start(c->mainloop) < 0) {
 577         goto unlock_and_fail;
 578     }
 579
 580     for (;;) {
 581         pa_context_state_t state;
 582
 583         state = pa_context_get_state(c->context);
 584
 585         if (state == PA_CONTEXT_READY) {
 586             break;
 587         }
 588
 589         if (!PA_CONTEXT_IS_GOOD(state)) {
 590             qpa_logerr(pa_context_errno(c->context),
 591                        "Wrong context state\n");
 592             goto unlock_and_fail;
 593         }
 594
 595         /* Wait until the context is ready */
 596         pa_threaded_mainloop_wait(c->mainloop);
 597     }
 598
 599     pa_threaded_mainloop_unlock(c->mainloop);
 600     return c;
 601
 602 unlock_and_fail:
 603     pa_threaded_mainloop_unlock(c->mainloop);
 604 fail:
 605     AUD_log (AUDIO_CAP, "Failed to initialize PA context");
 606     qpa_conn_fini(c);
 607     return NULL;
 608 }
 609
 610 static void *qpa_audio_init(Audiodev *dev)
 611 {
 612     paaudio *g;
 613     AudiodevPaOptions *popts = &dev->u.pa;
 614     const char *server;
 615     PAConnection *c;
 616
 617     assert(dev->driver == AUDIODEV_DRIVER_PA);
 618
 619     if (!popts->has_server) {
 620         char pidfile[64];
 621         char *runtime;
 622         struct stat st;
 623
 624         runtime = getenv("XDG_RUNTIME_DIR");
 625         if (!runtime) {
 626             return NULL;
 627         }
 628         snprintf(pidfile, sizeof(pidfile), "%s/pulse/pid", runtime);
 629         if (stat(pidfile, &st) != 0) {
 630             return NULL;
 631         }
 632     }
 633
 634     if (!qpa_validate_per_direction_opts(dev, popts->in)) {
 635         return NULL;
 636     }
 637     if (!qpa_validate_per_direction_opts(dev, popts->out)) {
 638         return NULL;
 639     }
 640
 641     g = g_malloc0(sizeof(paaudio));
 642     server = popts->has_server ? popts->server : NULL;
 643
 644     g->dev = dev;
 645
 646     QTAILQ_FOREACH(c, &pa_conns, list) {
 647         if (server == NULL || c->server == NULL ?
 648             server == c->server :
 649             strcmp(server, c->server) == 0) {
 650             g->conn = c;
 651             break;
 652         }
 653     }
 654     if (!g->conn) {
 655         g->conn = qpa_conn_init(server);
 656     }
 657     if (!g->conn) {
 658         g_free(g);
 659         return NULL;
 660     }
 661
 662     ++g->conn->refcount;
 663     return g;
 664 }
 665
 666 static void qpa_conn_fini(PAConnection *c)
 667 {
 668     if (c->mainloop) {
 669         pa_threaded_mainloop_stop(c->mainloop);
 670     }
 671
 672     if (c->context) {
 673         pa_context_disconnect(c->context);
 674         pa_context_unref(c->context);
 675     }
 676
 677     if (c->mainloop) {
 678         pa_threaded_mainloop_free(c->mainloop);
 679     }
 680
 681     QTAILQ_REMOVE(&pa_conns, c, list);
 682     g_free(c);
 683 }
 684
 685 static void qpa_audio_fini (void *opaque)
 686 {
 687     paaudio *g = opaque;
 688     PAConnection *c = g->conn;
 689
 690     if (--c->refcount == 0) {
 691         qpa_conn_fini(c);
 692     }
 693
 694     g_free(g);
 695 }
 696
 697 static struct audio_pcm_ops qpa_pcm_ops = {
 698     .init_out = qpa_init_out,
 699     .fini_out = qpa_fini_out,
 700     .write    = qpa_write,
 701     .volume_out = qpa_volume_out,
 702
 703     .init_in  = qpa_init_in,
 704     .fini_in  = qpa_fini_in,
 705     .read     = qpa_read,
 706     .volume_in = qpa_volume_in
 707 };
 708
 709 static struct audio_driver pa_audio_driver = {
 710     .name           = "pa",
 711     .descr          = "http://www.pulseaudio.org/",
 712     .init           = qpa_audio_init,
 713     .fini           = qpa_audio_fini,
 714     .pcm_ops        = &qpa_pcm_ops,
 715     .can_be_default = 1,
 716     .max_voices_out = INT_MAX,
 717     .max_voices_in  = INT_MAX,
 718     .voice_size_out = sizeof (PAVoiceOut),
 719     .voice_size_in  = sizeof (PAVoiceIn),
 720 };
 721
 722 static void register_audio_pa(void)
 723 {
 724     audio_driver_register(&pa_audio_driver);
 725 }
 726 type_init(register_audio_pa);