audio/coreaudio.c

   1 /*
   2  * QEMU OS X CoreAudio audio driver
   3  *
   4  * Copyright (c) 2005 Mike Kronenberg
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 #include "qemu/osdep.h"
  26 #include <CoreAudio/CoreAudio.h>
  27 #include <pthread.h>            /* pthread_X */
  28
  29 #include "qemu-common.h"
  30 #include "audio.h"
  31
  32 #define AUDIO_CAP "coreaudio"
  33 #include "audio_int.h"
  34
  35 #ifndef MAC_OS_X_VERSION_10_6
  36 #define MAC_OS_X_VERSION_10_6 1060
  37 #endif
  38
  39 typedef struct {
  40     int buffer_frames;
  41     int nbuffers;
  42 } CoreaudioConf;
  43
  44 typedef struct coreaudioVoiceOut {
  45     HWVoiceOut hw;
  46     pthread_mutex_t mutex;
  47     AudioDeviceID outputDeviceID;
  48     UInt32 audioDevicePropertyBufferFrameSize;
  49     AudioStreamBasicDescription outputStreamBasicDescription;
  50     AudioDeviceIOProcID ioprocid;
  51     int live;
  52     int decr;
  53     int rpos;
  54 } coreaudioVoiceOut;
  55
  56 #if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_6
  57 /* The APIs used here only become available from 10.6 */
  58
  59 static OSStatus coreaudio_get_voice(AudioDeviceID *id)
  60 {
  61     UInt32 size = sizeof(*id);
  62     AudioObjectPropertyAddress addr = {
  63         kAudioHardwarePropertyDefaultOutputDevice,
  64         kAudioObjectPropertyScopeGlobal,
  65         kAudioObjectPropertyElementMaster
  66     };
  67
  68     return AudioObjectGetPropertyData(kAudioObjectSystemObject,
  69                                       &addr,
  70                                       0,
  71                                       NULL,
  72                                       &size,
  73                                       id);
  74 }
  75
  76 static OSStatus coreaudio_get_framesizerange(AudioDeviceID id,
  77                                              AudioValueRange *framerange)
  78 {
  79     UInt32 size = sizeof(*framerange);
  80     AudioObjectPropertyAddress addr = {
  81         kAudioDevicePropertyBufferFrameSizeRange,
  82         kAudioDevicePropertyScopeOutput,
  83         kAudioObjectPropertyElementMaster
  84     };
  85
  86     return AudioObjectGetPropertyData(id,
  87                                       &addr,
  88                                       0,
  89                                       NULL,
  90                                       &size,
  91                                       framerange);
  92 }
  93
  94 static OSStatus coreaudio_get_framesize(AudioDeviceID id, UInt32 *framesize)
  95 {
  96     UInt32 size = sizeof(*framesize);
  97     AudioObjectPropertyAddress addr = {
  98         kAudioDevicePropertyBufferFrameSize,
  99         kAudioDevicePropertyScopeOutput,
 100         kAudioObjectPropertyElementMaster
 101     };
 102
 103     return AudioObjectGetPropertyData(id,
 104                                       &addr,
 105                                       0,
 106                                       NULL,
 107                                       &size,
 108                                       framesize);
 109 }
 110
 111 static OSStatus coreaudio_set_framesize(AudioDeviceID id, UInt32 *framesize)
 112 {
 113     UInt32 size = sizeof(*framesize);
 114     AudioObjectPropertyAddress addr = {
 115         kAudioDevicePropertyBufferFrameSize,
 116         kAudioDevicePropertyScopeOutput,
 117         kAudioObjectPropertyElementMaster
 118     };
 119
 120     return AudioObjectSetPropertyData(id,
 121                                       &addr,
 122                                       0,
 123                                       NULL,
 124                                       size,
 125                                       framesize);
 126 }
 127
 128 static OSStatus coreaudio_get_streamformat(AudioDeviceID id,
 129                                            AudioStreamBasicDescription *d)
 130 {
 131     UInt32 size = sizeof(*d);
 132     AudioObjectPropertyAddress addr = {
 133         kAudioDevicePropertyStreamFormat,
 134         kAudioDevicePropertyScopeOutput,
 135         kAudioObjectPropertyElementMaster
 136     };
 137
 138     return AudioObjectGetPropertyData(id,
 139                                       &addr,
 140                                       0,
 141                                       NULL,
 142                                       &size,
 143                                       d);
 144 }
 145
 146 static OSStatus coreaudio_set_streamformat(AudioDeviceID id,
 147                                            AudioStreamBasicDescription *d)
 148 {
 149     UInt32 size = sizeof(*d);
 150     AudioObjectPropertyAddress addr = {
 151         kAudioDevicePropertyStreamFormat,
 152         kAudioDevicePropertyScopeOutput,
 153         kAudioObjectPropertyElementMaster
 154     };
 155
 156     return AudioObjectSetPropertyData(id,
 157                                       &addr,
 158                                       0,
 159                                       NULL,
 160                                       size,
 161                                       d);
 162 }
 163
 164 static OSStatus coreaudio_get_isrunning(AudioDeviceID id, UInt32 *result)
 165 {
 166     UInt32 size = sizeof(*result);
 167     AudioObjectPropertyAddress addr = {
 168         kAudioDevicePropertyDeviceIsRunning,
 169         kAudioDevicePropertyScopeOutput,
 170         kAudioObjectPropertyElementMaster
 171     };
 172
 173     return AudioObjectGetPropertyData(id,
 174                                       &addr,
 175                                       0,
 176                                       NULL,
 177                                       &size,
 178                                       result);
 179 }
 180 #else
 181 /* Legacy versions of functions using deprecated APIs */
 182
 183 static OSStatus coreaudio_get_voice(AudioDeviceID *id)
 184 {
 185     UInt32 size = sizeof(*id);
 186
 187     return AudioHardwareGetProperty(
 188         kAudioHardwarePropertyDefaultOutputDevice,
 189         &size,
 190         id);
 191 }
 192
 193 static OSStatus coreaudio_get_framesizerange(AudioDeviceID id,
 194                                              AudioValueRange *framerange)
 195 {
 196     UInt32 size = sizeof(*framerange);
 197
 198     return AudioDeviceGetProperty(
 199         id,
 200         0,
 201         0,
 202         kAudioDevicePropertyBufferFrameSizeRange,
 203         &size,
 204         framerange);
 205 }
 206
 207 static OSStatus coreaudio_get_framesize(AudioDeviceID id, UInt32 *framesize)
 208 {
 209     UInt32 size = sizeof(*framesize);
 210
 211     return AudioDeviceGetProperty(
 212         id,
 213         0,
 214         false,
 215         kAudioDevicePropertyBufferFrameSize,
 216         &size,
 217         framesize);
 218 }
 219
 220 static OSStatus coreaudio_set_framesize(AudioDeviceID id, UInt32 *framesize)
 221 {
 222     UInt32 size = sizeof(*framesize);
 223
 224     return AudioDeviceSetProperty(
 225         id,
 226         NULL,
 227         0,
 228         false,
 229         kAudioDevicePropertyBufferFrameSize,
 230         size,
 231         framesize);
 232 }
 233
 234 static OSStatus coreaudio_get_streamformat(AudioDeviceID id,
 235                                            AudioStreamBasicDescription *d)
 236 {
 237     UInt32 size = sizeof(*d);
 238
 239     return AudioDeviceGetProperty(
 240         id,
 241         0,
 242         false,
 243         kAudioDevicePropertyStreamFormat,
 244         &size,
 245         d);
 246 }
 247
 248 static OSStatus coreaudio_set_streamformat(AudioDeviceID id,
 249                                            AudioStreamBasicDescription *d)
 250 {
 251     UInt32 size = sizeof(*d);
 252
 253     return AudioDeviceSetProperty(
 254         id,
 255         0,
 256         0,
 257         0,
 258         kAudioDevicePropertyStreamFormat,
 259         size,
 260         d);
 261 }
 262
 263 static OSStatus coreaudio_get_isrunning(AudioDeviceID id, UInt32 *result)
 264 {
 265     UInt32 size = sizeof(*result);
 266
 267     return AudioDeviceGetProperty(
 268         id,
 269         0,
 270         0,
 271         kAudioDevicePropertyDeviceIsRunning,
 272         &size,
 273         result);
 274 }
 275 #endif
 276
 277 static void coreaudio_logstatus (OSStatus status)
 278 {
 279     const char *str = "BUG";
 280
 281     switch(status) {
 282     case kAudioHardwareNoError:
 283         str = "kAudioHardwareNoError";
 284         break;
 285
 286     case kAudioHardwareNotRunningError:
 287         str = "kAudioHardwareNotRunningError";
 288         break;
 289
 290     case kAudioHardwareUnspecifiedError:
 291         str = "kAudioHardwareUnspecifiedError";
 292         break;
 293
 294     case kAudioHardwareUnknownPropertyError:
 295         str = "kAudioHardwareUnknownPropertyError";
 296         break;
 297
 298     case kAudioHardwareBadPropertySizeError:
 299         str = "kAudioHardwareBadPropertySizeError";
 300         break;
 301
 302     case kAudioHardwareIllegalOperationError:
 303         str = "kAudioHardwareIllegalOperationError";
 304         break;
 305
 306     case kAudioHardwareBadDeviceError:
 307         str = "kAudioHardwareBadDeviceError";
 308         break;
 309
 310     case kAudioHardwareBadStreamError:
 311         str = "kAudioHardwareBadStreamError";
 312         break;
 313
 314     case kAudioHardwareUnsupportedOperationError:
 315         str = "kAudioHardwareUnsupportedOperationError";
 316         break;
 317
 318     case kAudioDeviceUnsupportedFormatError:
 319         str = "kAudioDeviceUnsupportedFormatError";
 320         break;
 321
 322     case kAudioDevicePermissionsError:
 323         str = "kAudioDevicePermissionsError";
 324         break;
 325
 326     default:
 327         AUD_log (AUDIO_CAP, "Reason: status code %" PRId32 "\n", (int32_t)status);
 328         return;
 329     }
 330
 331     AUD_log (AUDIO_CAP, "Reason: %s\n", str);
 332 }
 333
 334 static void GCC_FMT_ATTR (2, 3) coreaudio_logerr (
 335     OSStatus status,
 336     const char *fmt,
 337     ...
 338     )
 339 {
 340     va_list ap;
 341
 342     va_start (ap, fmt);
 343     AUD_log (AUDIO_CAP, fmt, ap);
 344     va_end (ap);
 345
 346     coreaudio_logstatus (status);
 347 }
 348
 349 static void GCC_FMT_ATTR (3, 4) coreaudio_logerr2 (
 350     OSStatus status,
 351     const char *typ,
 352     const char *fmt,
 353     ...
 354     )
 355 {
 356     va_list ap;
 357
 358     AUD_log (AUDIO_CAP, "Could not initialize %s\n", typ);
 359
 360     va_start (ap, fmt);
 361     AUD_vlog (AUDIO_CAP, fmt, ap);
 362     va_end (ap);
 363
 364     coreaudio_logstatus (status);
 365 }
 366
 367 static inline UInt32 isPlaying (AudioDeviceID outputDeviceID)
 368 {
 369     OSStatus status;
 370     UInt32 result = 0;
 371     status = coreaudio_get_isrunning(outputDeviceID, &result);
 372     if (status != kAudioHardwareNoError) {
 373         coreaudio_logerr(status,
 374                          "Could not determine whether Device is playing\n");
 375     }
 376     return result;
 377 }
 378
 379 static int coreaudio_lock (coreaudioVoiceOut *core, const char *fn_name)
 380 {
 381     int err;
 382
 383     err = pthread_mutex_lock (&core->mutex);
 384     if (err) {
 385         dolog ("Could not lock voice for %s\nReason: %s\n",
 386                fn_name, strerror (err));
 387         return -1;
 388     }
 389     return 0;
 390 }
 391
 392 static int coreaudio_unlock (coreaudioVoiceOut *core, const char *fn_name)
 393 {
 394     int err;
 395
 396     err = pthread_mutex_unlock (&core->mutex);
 397     if (err) {
 398         dolog ("Could not unlock voice for %s\nReason: %s\n",
 399                fn_name, strerror (err));
 400         return -1;
 401     }
 402     return 0;
 403 }
 404
 405 static int coreaudio_run_out (HWVoiceOut *hw, int live)
 406 {
 407     int decr;
 408     coreaudioVoiceOut *core = (coreaudioVoiceOut *) hw;
 409
 410     if (coreaudio_lock (core, "coreaudio_run_out")) {
 411         return 0;
 412     }
 413
 414     if (core->decr > live) {
 415         ldebug ("core->decr %d live %d core->live %d\n",
 416                 core->decr,
 417                 live,
 418                 core->live);
 419     }
 420
 421     decr = audio_MIN (core->decr, live);
 422     core->decr -= decr;
 423
 424     core->live = live - decr;
 425     hw->rpos = core->rpos;
 426
 427     coreaudio_unlock (core, "coreaudio_run_out");
 428     return decr;
 429 }
 430
 431 /* callback to feed audiooutput buffer */
 432 static OSStatus audioDeviceIOProc(
 433     AudioDeviceID inDevice,
 434     const AudioTimeStamp* inNow,
 435     const AudioBufferList* inInputData,
 436     const AudioTimeStamp* inInputTime,
 437     AudioBufferList* outOutputData,
 438     const AudioTimeStamp* inOutputTime,
 439     void* hwptr)
 440 {
 441     UInt32 frame, frameCount;
 442     float *out = outOutputData->mBuffers[0].mData;
 443     HWVoiceOut *hw = hwptr;
 444     coreaudioVoiceOut *core = (coreaudioVoiceOut *) hwptr;
 445     int rpos, live;
 446     struct st_sample *src;
 447 #ifndef FLOAT_MIXENG
 448 #ifdef RECIPROCAL
 449     const float scale = 1.f / UINT_MAX;
 450 #else
 451     const float scale = UINT_MAX;
 452 #endif
 453 #endif
 454
 455     if (coreaudio_lock (core, "audioDeviceIOProc")) {
 456         inInputTime = 0;
 457         return 0;
 458     }
 459
 460     frameCount = core->audioDevicePropertyBufferFrameSize;
 461     live = core->live;
 462
 463     /* if there are not enough samples, set signal and return */
 464     if (live < frameCount) {
 465         inInputTime = 0;
 466         coreaudio_unlock (core, "audioDeviceIOProc(empty)");
 467         return 0;
 468     }
 469
 470     rpos = core->rpos;
 471     src = hw->mix_buf + rpos;
 472
 473     /* fill buffer */
 474     for (frame = 0; frame < frameCount; frame++) {
 475 #ifdef FLOAT_MIXENG
 476         *out++ = src[frame].l; /* left channel */
 477         *out++ = src[frame].r; /* right channel */
 478 #else
 479 #ifdef RECIPROCAL
 480         *out++ = src[frame].l * scale; /* left channel */
 481         *out++ = src[frame].r * scale; /* right channel */
 482 #else
 483         *out++ = src[frame].l / scale; /* left channel */
 484         *out++ = src[frame].r / scale; /* right channel */
 485 #endif
 486 #endif
 487     }
 488
 489     rpos = (rpos + frameCount) % hw->samples;
 490     core->decr += frameCount;
 491     core->rpos = rpos;
 492
 493     coreaudio_unlock (core, "audioDeviceIOProc");
 494     return 0;
 495 }
 496
 497 static int coreaudio_write (SWVoiceOut *sw, void *buf, int len)
 498 {
 499     return audio_pcm_sw_write (sw, buf, len);
 500 }
 501
 502 static int coreaudio_init_out(HWVoiceOut *hw, struct audsettings *as,
 503                               void *drv_opaque)
 504 {
 505     OSStatus status;
 506     coreaudioVoiceOut *core = (coreaudioVoiceOut *) hw;
 507     int err;
 508     const char *typ = "playback";
 509     AudioValueRange frameRange;
 510     CoreaudioConf *conf = drv_opaque;
 511
 512     /* create mutex */
 513     err = pthread_mutex_init(&core->mutex, NULL);
 514     if (err) {
 515         dolog("Could not create mutex\nReason: %s\n", strerror (err));
 516         return -1;
 517     }
 518
 519     audio_pcm_init_info (&hw->info, as);
 520
 521     status = coreaudio_get_voice(&core->outputDeviceID);
 522     if (status != kAudioHardwareNoError) {
 523         coreaudio_logerr2 (status, typ,
 524                            "Could not get default output Device\n");
 525         return -1;
 526     }
 527     if (core->outputDeviceID == kAudioDeviceUnknown) {
 528         dolog ("Could not initialize %s - Unknown Audiodevice\n", typ);
 529         return -1;
 530     }
 531
 532     /* get minimum and maximum buffer frame sizes */
 533     status = coreaudio_get_framesizerange(core->outputDeviceID,
 534                                           &frameRange);
 535     if (status != kAudioHardwareNoError) {
 536         coreaudio_logerr2 (status, typ,
 537                            "Could not get device buffer frame range\n");
 538         return -1;
 539     }
 540
 541     if (frameRange.mMinimum > conf->buffer_frames) {
 542         core->audioDevicePropertyBufferFrameSize = (UInt32) frameRange.mMinimum;
 543         dolog ("warning: Upsizing Buffer Frames to %f\n", frameRange.mMinimum);
 544     }
 545     else if (frameRange.mMaximum < conf->buffer_frames) {
 546         core->audioDevicePropertyBufferFrameSize = (UInt32) frameRange.mMaximum;
 547         dolog ("warning: Downsizing Buffer Frames to %f\n", frameRange.mMaximum);
 548     }
 549     else {
 550         core->audioDevicePropertyBufferFrameSize = conf->buffer_frames;
 551     }
 552
 553     /* set Buffer Frame Size */
 554     status = coreaudio_set_framesize(core->outputDeviceID,
 555                                      &core->audioDevicePropertyBufferFrameSize);
 556     if (status != kAudioHardwareNoError) {
 557         coreaudio_logerr2 (status, typ,
 558                            "Could not set device buffer frame size %" PRIu32 "\n",
 559                            (uint32_t)core->audioDevicePropertyBufferFrameSize);
 560         return -1;
 561     }
 562
 563     /* get Buffer Frame Size */
 564     status = coreaudio_get_framesize(core->outputDeviceID,
 565                                      &core->audioDevicePropertyBufferFrameSize);
 566     if (status != kAudioHardwareNoError) {
 567         coreaudio_logerr2 (status, typ,
 568                            "Could not get device buffer frame size\n");
 569         return -1;
 570     }
 571     hw->samples = conf->nbuffers * core->audioDevicePropertyBufferFrameSize;
 572
 573     /* get StreamFormat */
 574     status = coreaudio_get_streamformat(core->outputDeviceID,
 575                                         &core->outputStreamBasicDescription);
 576     if (status != kAudioHardwareNoError) {
 577         coreaudio_logerr2 (status, typ,
 578                            "Could not get Device Stream properties\n");
 579         core->outputDeviceID = kAudioDeviceUnknown;
 580         return -1;
 581     }
 582
 583     /* set Samplerate */
 584     core->outputStreamBasicDescription.mSampleRate = (Float64) as->freq;
 585     status = coreaudio_set_streamformat(core->outputDeviceID,
 586                                         &core->outputStreamBasicDescription);
 587     if (status != kAudioHardwareNoError) {
 588         coreaudio_logerr2 (status, typ, "Could not set samplerate %d\n",
 589                            as->freq);
 590         core->outputDeviceID = kAudioDeviceUnknown;
 591         return -1;
 592     }
 593
 594     /* set Callback */
 595     core->ioprocid = NULL;
 596     status = AudioDeviceCreateIOProcID(core->outputDeviceID,
 597                                        audioDeviceIOProc,
 598                                        hw,
 599                                        &core->ioprocid);
 600     if (status != kAudioHardwareNoError || core->ioprocid == NULL) {
 601         coreaudio_logerr2 (status, typ, "Could not set IOProc\n");
 602         core->outputDeviceID = kAudioDeviceUnknown;
 603         return -1;
 604     }
 605
 606     /* start Playback */
 607     if (!isPlaying(core->outputDeviceID)) {
 608         status = AudioDeviceStart(core->outputDeviceID, core->ioprocid);
 609         if (status != kAudioHardwareNoError) {
 610             coreaudio_logerr2 (status, typ, "Could not start playback\n");
 611             AudioDeviceDestroyIOProcID(core->outputDeviceID, core->ioprocid);
 612             core->outputDeviceID = kAudioDeviceUnknown;
 613             return -1;
 614         }
 615     }
 616
 617     return 0;
 618 }
 619
 620 static void coreaudio_fini_out (HWVoiceOut *hw)
 621 {
 622     OSStatus status;
 623     int err;
 624     coreaudioVoiceOut *core = (coreaudioVoiceOut *) hw;
 625
 626     if (!audio_is_cleaning_up()) {
 627         /* stop playback */
 628         if (isPlaying(core->outputDeviceID)) {
 629             status = AudioDeviceStop(core->outputDeviceID, core->ioprocid);
 630             if (status != kAudioHardwareNoError) {
 631                 coreaudio_logerr (status, "Could not stop playback\n");
 632             }
 633         }
 634
 635         /* remove callback */
 636         status = AudioDeviceDestroyIOProcID(core->outputDeviceID,
 637                                             core->ioprocid);
 638         if (status != kAudioHardwareNoError) {
 639             coreaudio_logerr (status, "Could not remove IOProc\n");
 640         }
 641     }
 642     core->outputDeviceID = kAudioDeviceUnknown;
 643
 644     /* destroy mutex */
 645     err = pthread_mutex_destroy(&core->mutex);
 646     if (err) {
 647         dolog("Could not destroy mutex\nReason: %s\n", strerror (err));
 648     }
 649 }
 650
 651 static int coreaudio_ctl_out (HWVoiceOut *hw, int cmd, ...)
 652 {
 653     OSStatus status;
 654     coreaudioVoiceOut *core = (coreaudioVoiceOut *) hw;
 655
 656     switch (cmd) {
 657     case VOICE_ENABLE:
 658         /* start playback */
 659         if (!isPlaying(core->outputDeviceID)) {
 660             status = AudioDeviceStart(core->outputDeviceID, core->ioprocid);
 661             if (status != kAudioHardwareNoError) {
 662                 coreaudio_logerr (status, "Could not resume playback\n");
 663             }
 664         }
 665         break;
 666
 667     case VOICE_DISABLE:
 668         /* stop playback */
 669         if (!audio_is_cleaning_up()) {
 670             if (isPlaying(core->outputDeviceID)) {
 671                 status = AudioDeviceStop(core->outputDeviceID,
 672                                          core->ioprocid);
 673                 if (status != kAudioHardwareNoError) {
 674                     coreaudio_logerr (status, "Could not pause playback\n");
 675                 }
 676             }
 677         }
 678         break;
 679     }
 680     return 0;
 681 }
 682
 683 static CoreaudioConf glob_conf = {
 684     .buffer_frames = 512,
 685     .nbuffers = 4,
 686 };
 687
 688 static void *coreaudio_audio_init (void)
 689 {
 690     CoreaudioConf *conf = g_malloc(sizeof(CoreaudioConf));
 691     *conf = glob_conf;
 692
 693     return conf;
 694 }
 695
 696 static void coreaudio_audio_fini (void *opaque)
 697 {
 698     g_free(opaque);
 699 }
 700
 701 static struct audio_option coreaudio_options[] = {
 702     {
 703         .name  = "BUFFER_SIZE",
 704         .tag   = AUD_OPT_INT,
 705         .valp  = &glob_conf.buffer_frames,
 706         .descr = "Size of the buffer in frames"
 707     },
 708     {
 709         .name  = "BUFFER_COUNT",
 710         .tag   = AUD_OPT_INT,
 711         .valp  = &glob_conf.nbuffers,
 712         .descr = "Number of buffers"
 713     },
 714     { /* End of list */ }
 715 };
 716
 717 static struct audio_pcm_ops coreaudio_pcm_ops = {
 718     .init_out = coreaudio_init_out,
 719     .fini_out = coreaudio_fini_out,
 720     .run_out  = coreaudio_run_out,
 721     .write    = coreaudio_write,
 722     .ctl_out  = coreaudio_ctl_out
 723 };
 724
 725 struct audio_driver coreaudio_audio_driver = {
 726     .name           = "coreaudio",
 727     .descr          = "CoreAudio http://developer.apple.com/audio/coreaudio.html",
 728     .options        = coreaudio_options,
 729     .init           = coreaudio_audio_init,
 730     .fini           = coreaudio_audio_fini,
 731     .pcm_ops        = &coreaudio_pcm_ops,
 732     .can_be_default = 1,
 733     .max_voices_out = 1,
 734     .max_voices_in  = 0,
 735     .voice_size_out = sizeof (coreaudioVoiceOut),
 736     .voice_size_in  = 0
 737 };