qemu/audio/alsaaudio.c
<<
>>
Prefs
   1/*
   2 * QEMU ALSA audio driver
   3 *
   4 * Copyright (c) 2005 Vassili Karpov (malc)
   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#include <alsa/asoundlib.h>
  25#include "qemu-common.h"
  26#include "qemu/main-loop.h"
  27#include "audio.h"
  28#include "trace.h"
  29
  30#if QEMU_GNUC_PREREQ(4, 3)
  31#pragma GCC diagnostic ignored "-Waddress"
  32#endif
  33
  34#define AUDIO_CAP "alsa"
  35#include "audio_int.h"
  36
  37typedef struct ALSAConf {
  38    int size_in_usec_in;
  39    int size_in_usec_out;
  40    const char *pcm_name_in;
  41    const char *pcm_name_out;
  42    unsigned int buffer_size_in;
  43    unsigned int period_size_in;
  44    unsigned int buffer_size_out;
  45    unsigned int period_size_out;
  46    unsigned int threshold;
  47
  48    int buffer_size_in_overridden;
  49    int period_size_in_overridden;
  50
  51    int buffer_size_out_overridden;
  52    int period_size_out_overridden;
  53} ALSAConf;
  54
  55struct pollhlp {
  56    snd_pcm_t *handle;
  57    struct pollfd *pfds;
  58    ALSAConf *conf;
  59    int count;
  60    int mask;
  61};
  62
  63typedef struct ALSAVoiceOut {
  64    HWVoiceOut hw;
  65    int wpos;
  66    int pending;
  67    void *pcm_buf;
  68    snd_pcm_t *handle;
  69    struct pollhlp pollhlp;
  70} ALSAVoiceOut;
  71
  72typedef struct ALSAVoiceIn {
  73    HWVoiceIn hw;
  74    snd_pcm_t *handle;
  75    void *pcm_buf;
  76    struct pollhlp pollhlp;
  77} ALSAVoiceIn;
  78
  79struct alsa_params_req {
  80    int freq;
  81    snd_pcm_format_t fmt;
  82    int nchannels;
  83    int size_in_usec;
  84    int override_mask;
  85    unsigned int buffer_size;
  86    unsigned int period_size;
  87};
  88
  89struct alsa_params_obt {
  90    int freq;
  91    audfmt_e fmt;
  92    int endianness;
  93    int nchannels;
  94    snd_pcm_uframes_t samples;
  95};
  96
  97static void GCC_FMT_ATTR (2, 3) alsa_logerr (int err, const char *fmt, ...)
  98{
  99    va_list ap;
 100
 101    va_start (ap, fmt);
 102    AUD_vlog (AUDIO_CAP, fmt, ap);
 103    va_end (ap);
 104
 105    AUD_log (AUDIO_CAP, "Reason: %s\n", snd_strerror (err));
 106}
 107
 108static void GCC_FMT_ATTR (3, 4) alsa_logerr2 (
 109    int err,
 110    const char *typ,
 111    const char *fmt,
 112    ...
 113    )
 114{
 115    va_list ap;
 116
 117    AUD_log (AUDIO_CAP, "Could not initialize %s\n", typ);
 118
 119    va_start (ap, fmt);
 120    AUD_vlog (AUDIO_CAP, fmt, ap);
 121    va_end (ap);
 122
 123    AUD_log (AUDIO_CAP, "Reason: %s\n", snd_strerror (err));
 124}
 125
 126static void alsa_fini_poll (struct pollhlp *hlp)
 127{
 128    int i;
 129    struct pollfd *pfds = hlp->pfds;
 130
 131    if (pfds) {
 132        for (i = 0; i < hlp->count; ++i) {
 133            qemu_set_fd_handler (pfds[i].fd, NULL, NULL, NULL);
 134        }
 135        g_free (pfds);
 136    }
 137    hlp->pfds = NULL;
 138    hlp->count = 0;
 139    hlp->handle = NULL;
 140}
 141
 142static void alsa_anal_close1 (snd_pcm_t **handlep)
 143{
 144    int err = snd_pcm_close (*handlep);
 145    if (err) {
 146        alsa_logerr (err, "Failed to close PCM handle %p\n", *handlep);
 147    }
 148    *handlep = NULL;
 149}
 150
 151static void alsa_anal_close (snd_pcm_t **handlep, struct pollhlp *hlp)
 152{
 153    alsa_fini_poll (hlp);
 154    alsa_anal_close1 (handlep);
 155}
 156
 157static int alsa_recover (snd_pcm_t *handle)
 158{
 159    int err = snd_pcm_prepare (handle);
 160    if (err < 0) {
 161        alsa_logerr (err, "Failed to prepare handle %p\n", handle);
 162        return -1;
 163    }
 164    return 0;
 165}
 166
 167static int alsa_resume (snd_pcm_t *handle)
 168{
 169    int err = snd_pcm_resume (handle);
 170    if (err < 0) {
 171        alsa_logerr (err, "Failed to resume handle %p\n", handle);
 172        return -1;
 173    }
 174    return 0;
 175}
 176
 177static void alsa_poll_handler (void *opaque)
 178{
 179    int err, count;
 180    snd_pcm_state_t state;
 181    struct pollhlp *hlp = opaque;
 182    unsigned short revents;
 183
 184    count = poll (hlp->pfds, hlp->count, 0);
 185    if (count < 0) {
 186        dolog ("alsa_poll_handler: poll %s\n", strerror (errno));
 187        return;
 188    }
 189
 190    if (!count) {
 191        return;
 192    }
 193
 194    /* XXX: ALSA example uses initial count, not the one returned by
 195       poll, correct? */
 196    err = snd_pcm_poll_descriptors_revents (hlp->handle, hlp->pfds,
 197                                            hlp->count, &revents);
 198    if (err < 0) {
 199        alsa_logerr (err, "snd_pcm_poll_descriptors_revents");
 200        return;
 201    }
 202
 203    if (!(revents & hlp->mask)) {
 204        trace_alsa_revents(revents);
 205        return;
 206    }
 207
 208    state = snd_pcm_state (hlp->handle);
 209    switch (state) {
 210    case SND_PCM_STATE_SETUP:
 211        alsa_recover (hlp->handle);
 212        break;
 213
 214    case SND_PCM_STATE_XRUN:
 215        alsa_recover (hlp->handle);
 216        break;
 217
 218    case SND_PCM_STATE_SUSPENDED:
 219        alsa_resume (hlp->handle);
 220        break;
 221
 222    case SND_PCM_STATE_PREPARED:
 223        audio_run ("alsa run (prepared)");
 224        break;
 225
 226    case SND_PCM_STATE_RUNNING:
 227        audio_run ("alsa run (running)");
 228        break;
 229
 230    default:
 231        dolog ("Unexpected state %d\n", state);
 232    }
 233}
 234
 235static int alsa_poll_helper (snd_pcm_t *handle, struct pollhlp *hlp, int mask)
 236{
 237    int i, count, err;
 238    struct pollfd *pfds;
 239
 240    count = snd_pcm_poll_descriptors_count (handle);
 241    if (count <= 0) {
 242        dolog ("Could not initialize poll mode\n"
 243               "Invalid number of poll descriptors %d\n", count);
 244        return -1;
 245    }
 246
 247    pfds = audio_calloc ("alsa_poll_helper", count, sizeof (*pfds));
 248    if (!pfds) {
 249        dolog ("Could not initialize poll mode\n");
 250        return -1;
 251    }
 252
 253    err = snd_pcm_poll_descriptors (handle, pfds, count);
 254    if (err < 0) {
 255        alsa_logerr (err, "Could not initialize poll mode\n"
 256                     "Could not obtain poll descriptors\n");
 257        g_free (pfds);
 258        return -1;
 259    }
 260
 261    for (i = 0; i < count; ++i) {
 262        if (pfds[i].events & POLLIN) {
 263            qemu_set_fd_handler (pfds[i].fd, alsa_poll_handler, NULL, hlp);
 264        }
 265        if (pfds[i].events & POLLOUT) {
 266            trace_alsa_pollout(i, pfds[i].fd);
 267            qemu_set_fd_handler (pfds[i].fd, NULL, alsa_poll_handler, hlp);
 268        }
 269        trace_alsa_set_handler(pfds[i].events, i, pfds[i].fd, err);
 270
 271    }
 272    hlp->pfds = pfds;
 273    hlp->count = count;
 274    hlp->handle = handle;
 275    hlp->mask = mask;
 276    return 0;
 277}
 278
 279static int alsa_poll_out (HWVoiceOut *hw)
 280{
 281    ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
 282
 283    return alsa_poll_helper (alsa->handle, &alsa->pollhlp, POLLOUT);
 284}
 285
 286static int alsa_poll_in (HWVoiceIn *hw)
 287{
 288    ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
 289
 290    return alsa_poll_helper (alsa->handle, &alsa->pollhlp, POLLIN);
 291}
 292
 293static int alsa_write (SWVoiceOut *sw, void *buf, int len)
 294{
 295    return audio_pcm_sw_write (sw, buf, len);
 296}
 297
 298static snd_pcm_format_t aud_to_alsafmt (audfmt_e fmt, int endianness)
 299{
 300    switch (fmt) {
 301    case AUD_FMT_S8:
 302        return SND_PCM_FORMAT_S8;
 303
 304    case AUD_FMT_U8:
 305        return SND_PCM_FORMAT_U8;
 306
 307    case AUD_FMT_S16:
 308        if (endianness) {
 309            return SND_PCM_FORMAT_S16_BE;
 310        }
 311        else {
 312            return SND_PCM_FORMAT_S16_LE;
 313        }
 314
 315    case AUD_FMT_U16:
 316        if (endianness) {
 317            return SND_PCM_FORMAT_U16_BE;
 318        }
 319        else {
 320            return SND_PCM_FORMAT_U16_LE;
 321        }
 322
 323    case AUD_FMT_S32:
 324        if (endianness) {
 325            return SND_PCM_FORMAT_S32_BE;
 326        }
 327        else {
 328            return SND_PCM_FORMAT_S32_LE;
 329        }
 330
 331    case AUD_FMT_U32:
 332        if (endianness) {
 333            return SND_PCM_FORMAT_U32_BE;
 334        }
 335        else {
 336            return SND_PCM_FORMAT_U32_LE;
 337        }
 338
 339    default:
 340        dolog ("Internal logic error: Bad audio format %d\n", fmt);
 341#ifdef DEBUG_AUDIO
 342        abort ();
 343#endif
 344        return SND_PCM_FORMAT_U8;
 345    }
 346}
 347
 348static int alsa_to_audfmt (snd_pcm_format_t alsafmt, audfmt_e *fmt,
 349                           int *endianness)
 350{
 351    switch (alsafmt) {
 352    case SND_PCM_FORMAT_S8:
 353        *endianness = 0;
 354        *fmt = AUD_FMT_S8;
 355        break;
 356
 357    case SND_PCM_FORMAT_U8:
 358        *endianness = 0;
 359        *fmt = AUD_FMT_U8;
 360        break;
 361
 362    case SND_PCM_FORMAT_S16_LE:
 363        *endianness = 0;
 364        *fmt = AUD_FMT_S16;
 365        break;
 366
 367    case SND_PCM_FORMAT_U16_LE:
 368        *endianness = 0;
 369        *fmt = AUD_FMT_U16;
 370        break;
 371
 372    case SND_PCM_FORMAT_S16_BE:
 373        *endianness = 1;
 374        *fmt = AUD_FMT_S16;
 375        break;
 376
 377    case SND_PCM_FORMAT_U16_BE:
 378        *endianness = 1;
 379        *fmt = AUD_FMT_U16;
 380        break;
 381
 382    case SND_PCM_FORMAT_S32_LE:
 383        *endianness = 0;
 384        *fmt = AUD_FMT_S32;
 385        break;
 386
 387    case SND_PCM_FORMAT_U32_LE:
 388        *endianness = 0;
 389        *fmt = AUD_FMT_U32;
 390        break;
 391
 392    case SND_PCM_FORMAT_S32_BE:
 393        *endianness = 1;
 394        *fmt = AUD_FMT_S32;
 395        break;
 396
 397    case SND_PCM_FORMAT_U32_BE:
 398        *endianness = 1;
 399        *fmt = AUD_FMT_U32;
 400        break;
 401
 402    default:
 403        dolog ("Unrecognized audio format %d\n", alsafmt);
 404        return -1;
 405    }
 406
 407    return 0;
 408}
 409
 410static void alsa_dump_info (struct alsa_params_req *req,
 411                            struct alsa_params_obt *obt,
 412                            snd_pcm_format_t obtfmt)
 413{
 414    dolog ("parameter | requested value | obtained value\n");
 415    dolog ("format    |      %10d |     %10d\n", req->fmt, obtfmt);
 416    dolog ("channels  |      %10d |     %10d\n",
 417           req->nchannels, obt->nchannels);
 418    dolog ("frequency |      %10d |     %10d\n", req->freq, obt->freq);
 419    dolog ("============================================\n");
 420    dolog ("requested: buffer size %d period size %d\n",
 421           req->buffer_size, req->period_size);
 422    dolog ("obtained: samples %ld\n", obt->samples);
 423}
 424
 425static void alsa_set_threshold (snd_pcm_t *handle, snd_pcm_uframes_t threshold)
 426{
 427    int err;
 428    snd_pcm_sw_params_t *sw_params;
 429
 430    snd_pcm_sw_params_alloca (&sw_params);
 431
 432    err = snd_pcm_sw_params_current (handle, sw_params);
 433    if (err < 0) {
 434        dolog ("Could not fully initialize DAC\n");
 435        alsa_logerr (err, "Failed to get current software parameters\n");
 436        return;
 437    }
 438
 439    err = snd_pcm_sw_params_set_start_threshold (handle, sw_params, threshold);
 440    if (err < 0) {
 441        dolog ("Could not fully initialize DAC\n");
 442        alsa_logerr (err, "Failed to set software threshold to %ld\n",
 443                     threshold);
 444        return;
 445    }
 446
 447    err = snd_pcm_sw_params (handle, sw_params);
 448    if (err < 0) {
 449        dolog ("Could not fully initialize DAC\n");
 450        alsa_logerr (err, "Failed to set software parameters\n");
 451        return;
 452    }
 453}
 454
 455static int alsa_open (int in, struct alsa_params_req *req,
 456                      struct alsa_params_obt *obt, snd_pcm_t **handlep,
 457                      ALSAConf *conf)
 458{
 459    snd_pcm_t *handle;
 460    snd_pcm_hw_params_t *hw_params;
 461    int err;
 462    int size_in_usec;
 463    unsigned int freq, nchannels;
 464    const char *pcm_name = in ? conf->pcm_name_in : conf->pcm_name_out;
 465    snd_pcm_uframes_t obt_buffer_size;
 466    const char *typ = in ? "ADC" : "DAC";
 467    snd_pcm_format_t obtfmt;
 468
 469    freq = req->freq;
 470    nchannels = req->nchannels;
 471    size_in_usec = req->size_in_usec;
 472
 473    snd_pcm_hw_params_alloca (&hw_params);
 474
 475    err = snd_pcm_open (
 476        &handle,
 477        pcm_name,
 478        in ? SND_PCM_STREAM_CAPTURE : SND_PCM_STREAM_PLAYBACK,
 479        SND_PCM_NONBLOCK
 480        );
 481    if (err < 0) {
 482        alsa_logerr2 (err, typ, "Failed to open `%s':\n", pcm_name);
 483        return -1;
 484    }
 485
 486    err = snd_pcm_hw_params_any (handle, hw_params);
 487    if (err < 0) {
 488        alsa_logerr2 (err, typ, "Failed to initialize hardware parameters\n");
 489        goto err;
 490    }
 491
 492    err = snd_pcm_hw_params_set_access (
 493        handle,
 494        hw_params,
 495        SND_PCM_ACCESS_RW_INTERLEAVED
 496        );
 497    if (err < 0) {
 498        alsa_logerr2 (err, typ, "Failed to set access type\n");
 499        goto err;
 500    }
 501
 502    err = snd_pcm_hw_params_set_format (handle, hw_params, req->fmt);
 503    if (err < 0) {
 504        alsa_logerr2 (err, typ, "Failed to set format %d\n", req->fmt);
 505    }
 506
 507    err = snd_pcm_hw_params_set_rate_near (handle, hw_params, &freq, 0);
 508    if (err < 0) {
 509        alsa_logerr2 (err, typ, "Failed to set frequency %d\n", req->freq);
 510        goto err;
 511    }
 512
 513    err = snd_pcm_hw_params_set_channels_near (
 514        handle,
 515        hw_params,
 516        &nchannels
 517        );
 518    if (err < 0) {
 519        alsa_logerr2 (err, typ, "Failed to set number of channels %d\n",
 520                      req->nchannels);
 521        goto err;
 522    }
 523
 524    if (nchannels != 1 && nchannels != 2) {
 525        alsa_logerr2 (err, typ,
 526                      "Can not handle obtained number of channels %d\n",
 527                      nchannels);
 528        goto err;
 529    }
 530
 531    if (req->buffer_size) {
 532        unsigned long obt;
 533
 534        if (size_in_usec) {
 535            int dir = 0;
 536            unsigned int btime = req->buffer_size;
 537
 538            err = snd_pcm_hw_params_set_buffer_time_near (
 539                handle,
 540                hw_params,
 541                &btime,
 542                &dir
 543                );
 544            obt = btime;
 545        }
 546        else {
 547            snd_pcm_uframes_t bsize = req->buffer_size;
 548
 549            err = snd_pcm_hw_params_set_buffer_size_near (
 550                handle,
 551                hw_params,
 552                &bsize
 553                );
 554            obt = bsize;
 555        }
 556        if (err < 0) {
 557            alsa_logerr2 (err, typ, "Failed to set buffer %s to %d\n",
 558                          size_in_usec ? "time" : "size", req->buffer_size);
 559            goto err;
 560        }
 561
 562        if ((req->override_mask & 2) && (obt - req->buffer_size))
 563            dolog ("Requested buffer %s %u was rejected, using %lu\n",
 564                   size_in_usec ? "time" : "size", req->buffer_size, obt);
 565    }
 566
 567    if (req->period_size) {
 568        unsigned long obt;
 569
 570        if (size_in_usec) {
 571            int dir = 0;
 572            unsigned int ptime = req->period_size;
 573
 574            err = snd_pcm_hw_params_set_period_time_near (
 575                handle,
 576                hw_params,
 577                &ptime,
 578                &dir
 579                );
 580            obt = ptime;
 581        }
 582        else {
 583            int dir = 0;
 584            snd_pcm_uframes_t psize = req->period_size;
 585
 586            err = snd_pcm_hw_params_set_period_size_near (
 587                handle,
 588                hw_params,
 589                &psize,
 590                &dir
 591                );
 592            obt = psize;
 593        }
 594
 595        if (err < 0) {
 596            alsa_logerr2 (err, typ, "Failed to set period %s to %d\n",
 597                          size_in_usec ? "time" : "size", req->period_size);
 598            goto err;
 599        }
 600
 601        if (((req->override_mask & 1) && (obt - req->period_size)))
 602            dolog ("Requested period %s %u was rejected, using %lu\n",
 603                   size_in_usec ? "time" : "size", req->period_size, obt);
 604    }
 605
 606    err = snd_pcm_hw_params (handle, hw_params);
 607    if (err < 0) {
 608        alsa_logerr2 (err, typ, "Failed to apply audio parameters\n");
 609        goto err;
 610    }
 611
 612    err = snd_pcm_hw_params_get_buffer_size (hw_params, &obt_buffer_size);
 613    if (err < 0) {
 614        alsa_logerr2 (err, typ, "Failed to get buffer size\n");
 615        goto err;
 616    }
 617
 618    err = snd_pcm_hw_params_get_format (hw_params, &obtfmt);
 619    if (err < 0) {
 620        alsa_logerr2 (err, typ, "Failed to get format\n");
 621        goto err;
 622    }
 623
 624    if (alsa_to_audfmt (obtfmt, &obt->fmt, &obt->endianness)) {
 625        dolog ("Invalid format was returned %d\n", obtfmt);
 626        goto err;
 627    }
 628
 629    err = snd_pcm_prepare (handle);
 630    if (err < 0) {
 631        alsa_logerr2 (err, typ, "Could not prepare handle %p\n", handle);
 632        goto err;
 633    }
 634
 635    if (!in && conf->threshold) {
 636        snd_pcm_uframes_t threshold;
 637        int bytes_per_sec;
 638
 639        bytes_per_sec = freq << (nchannels == 2);
 640
 641        switch (obt->fmt) {
 642        case AUD_FMT_S8:
 643        case AUD_FMT_U8:
 644            break;
 645
 646        case AUD_FMT_S16:
 647        case AUD_FMT_U16:
 648            bytes_per_sec <<= 1;
 649            break;
 650
 651        case AUD_FMT_S32:
 652        case AUD_FMT_U32:
 653            bytes_per_sec <<= 2;
 654            break;
 655        }
 656
 657        threshold = (conf->threshold * bytes_per_sec) / 1000;
 658        alsa_set_threshold (handle, threshold);
 659    }
 660
 661    obt->nchannels = nchannels;
 662    obt->freq = freq;
 663    obt->samples = obt_buffer_size;
 664
 665    *handlep = handle;
 666
 667    if (obtfmt != req->fmt ||
 668         obt->nchannels != req->nchannels ||
 669         obt->freq != req->freq) {
 670        dolog ("Audio parameters for %s\n", typ);
 671        alsa_dump_info (req, obt, obtfmt);
 672    }
 673
 674#ifdef DEBUG
 675    alsa_dump_info (req, obt, obtfmt);
 676#endif
 677    return 0;
 678
 679 err:
 680    alsa_anal_close1 (&handle);
 681    return -1;
 682}
 683
 684static snd_pcm_sframes_t alsa_get_avail (snd_pcm_t *handle)
 685{
 686    snd_pcm_sframes_t avail;
 687
 688    avail = snd_pcm_avail_update (handle);
 689    if (avail < 0) {
 690        if (avail == -EPIPE) {
 691            if (!alsa_recover (handle)) {
 692                avail = snd_pcm_avail_update (handle);
 693            }
 694        }
 695
 696        if (avail < 0) {
 697            alsa_logerr (avail,
 698                         "Could not obtain number of available frames\n");
 699            return -1;
 700        }
 701    }
 702
 703    return avail;
 704}
 705
 706static void alsa_write_pending (ALSAVoiceOut *alsa)
 707{
 708    HWVoiceOut *hw = &alsa->hw;
 709
 710    while (alsa->pending) {
 711        int left_till_end_samples = hw->samples - alsa->wpos;
 712        int len = audio_MIN (alsa->pending, left_till_end_samples);
 713        char *src = advance (alsa->pcm_buf, alsa->wpos << hw->info.shift);
 714
 715        while (len) {
 716            snd_pcm_sframes_t written;
 717
 718            written = snd_pcm_writei (alsa->handle, src, len);
 719
 720            if (written <= 0) {
 721                switch (written) {
 722                case 0:
 723                    trace_alsa_wrote_zero(len);
 724                    return;
 725
 726                case -EPIPE:
 727                    if (alsa_recover (alsa->handle)) {
 728                        alsa_logerr (written, "Failed to write %d frames\n",
 729                                     len);
 730                        return;
 731                    }
 732                    trace_alsa_xrun_out();
 733                    continue;
 734
 735                case -ESTRPIPE:
 736                    /* stream is suspended and waiting for an
 737                       application recovery */
 738                    if (alsa_resume (alsa->handle)) {
 739                        alsa_logerr (written, "Failed to write %d frames\n",
 740                                     len);
 741                        return;
 742                    }
 743                    trace_alsa_resume_out();
 744                    continue;
 745
 746                case -EAGAIN:
 747                    return;
 748
 749                default:
 750                    alsa_logerr (written, "Failed to write %d frames from %p\n",
 751                                 len, src);
 752                    return;
 753                }
 754            }
 755
 756            alsa->wpos = (alsa->wpos + written) % hw->samples;
 757            alsa->pending -= written;
 758            len -= written;
 759        }
 760    }
 761}
 762
 763static int alsa_run_out (HWVoiceOut *hw, int live)
 764{
 765    ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
 766    int decr;
 767    snd_pcm_sframes_t avail;
 768
 769    avail = alsa_get_avail (alsa->handle);
 770    if (avail < 0) {
 771        dolog ("Could not get number of available playback frames\n");
 772        return 0;
 773    }
 774
 775    decr = audio_MIN (live, avail);
 776    decr = audio_pcm_hw_clip_out (hw, alsa->pcm_buf, decr, alsa->pending);
 777    alsa->pending += decr;
 778    alsa_write_pending (alsa);
 779    return decr;
 780}
 781
 782static void alsa_fini_out (HWVoiceOut *hw)
 783{
 784    ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
 785
 786    ldebug ("alsa_fini\n");
 787    alsa_anal_close (&alsa->handle, &alsa->pollhlp);
 788
 789    g_free(alsa->pcm_buf);
 790    alsa->pcm_buf = NULL;
 791}
 792
 793static int alsa_init_out(HWVoiceOut *hw, struct audsettings *as,
 794                         void *drv_opaque)
 795{
 796    ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
 797    struct alsa_params_req req;
 798    struct alsa_params_obt obt;
 799    snd_pcm_t *handle;
 800    struct audsettings obt_as;
 801    ALSAConf *conf = drv_opaque;
 802
 803    req.fmt = aud_to_alsafmt (as->fmt, as->endianness);
 804    req.freq = as->freq;
 805    req.nchannels = as->nchannels;
 806    req.period_size = conf->period_size_out;
 807    req.buffer_size = conf->buffer_size_out;
 808    req.size_in_usec = conf->size_in_usec_out;
 809    req.override_mask =
 810        (conf->period_size_out_overridden ? 1 : 0) |
 811        (conf->buffer_size_out_overridden ? 2 : 0);
 812
 813    if (alsa_open (0, &req, &obt, &handle, conf)) {
 814        return -1;
 815    }
 816
 817    obt_as.freq = obt.freq;
 818    obt_as.nchannels = obt.nchannels;
 819    obt_as.fmt = obt.fmt;
 820    obt_as.endianness = obt.endianness;
 821
 822    audio_pcm_init_info (&hw->info, &obt_as);
 823    hw->samples = obt.samples;
 824
 825    alsa->pcm_buf = audio_calloc (AUDIO_FUNC, obt.samples, 1 << hw->info.shift);
 826    if (!alsa->pcm_buf) {
 827        dolog ("Could not allocate DAC buffer (%d samples, each %d bytes)\n",
 828               hw->samples, 1 << hw->info.shift);
 829        alsa_anal_close1 (&handle);
 830        return -1;
 831    }
 832
 833    alsa->handle = handle;
 834    alsa->pollhlp.conf = conf;
 835    return 0;
 836}
 837
 838#define VOICE_CTL_PAUSE 0
 839#define VOICE_CTL_PREPARE 1
 840#define VOICE_CTL_START 2
 841
 842static int alsa_voice_ctl (snd_pcm_t *handle, const char *typ, int ctl)
 843{
 844    int err;
 845
 846    if (ctl == VOICE_CTL_PAUSE) {
 847        err = snd_pcm_drop (handle);
 848        if (err < 0) {
 849            alsa_logerr (err, "Could not stop %s\n", typ);
 850            return -1;
 851        }
 852    }
 853    else {
 854        err = snd_pcm_prepare (handle);
 855        if (err < 0) {
 856            alsa_logerr (err, "Could not prepare handle for %s\n", typ);
 857            return -1;
 858        }
 859        if (ctl == VOICE_CTL_START) {
 860            err = snd_pcm_start(handle);
 861            if (err < 0) {
 862                alsa_logerr (err, "Could not start handle for %s\n", typ);
 863                return -1;
 864            }
 865        }
 866    }
 867
 868    return 0;
 869}
 870
 871static int alsa_ctl_out (HWVoiceOut *hw, int cmd, ...)
 872{
 873    ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
 874
 875    switch (cmd) {
 876    case VOICE_ENABLE:
 877        {
 878            va_list ap;
 879            int poll_mode;
 880
 881            va_start (ap, cmd);
 882            poll_mode = va_arg (ap, int);
 883            va_end (ap);
 884
 885            ldebug ("enabling voice\n");
 886            if (poll_mode && alsa_poll_out (hw)) {
 887                poll_mode = 0;
 888            }
 889            hw->poll_mode = poll_mode;
 890            return alsa_voice_ctl (alsa->handle, "playback", VOICE_CTL_PREPARE);
 891        }
 892
 893    case VOICE_DISABLE:
 894        ldebug ("disabling voice\n");
 895        if (hw->poll_mode) {
 896            hw->poll_mode = 0;
 897            alsa_fini_poll (&alsa->pollhlp);
 898        }
 899        return alsa_voice_ctl (alsa->handle, "playback", VOICE_CTL_PAUSE);
 900    }
 901
 902    return -1;
 903}
 904
 905static int alsa_init_in(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque)
 906{
 907    ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
 908    struct alsa_params_req req;
 909    struct alsa_params_obt obt;
 910    snd_pcm_t *handle;
 911    struct audsettings obt_as;
 912    ALSAConf *conf = drv_opaque;
 913
 914    req.fmt = aud_to_alsafmt (as->fmt, as->endianness);
 915    req.freq = as->freq;
 916    req.nchannels = as->nchannels;
 917    req.period_size = conf->period_size_in;
 918    req.buffer_size = conf->buffer_size_in;
 919    req.size_in_usec = conf->size_in_usec_in;
 920    req.override_mask =
 921        (conf->period_size_in_overridden ? 1 : 0) |
 922        (conf->buffer_size_in_overridden ? 2 : 0);
 923
 924    if (alsa_open (1, &req, &obt, &handle, conf)) {
 925        return -1;
 926    }
 927
 928    obt_as.freq = obt.freq;
 929    obt_as.nchannels = obt.nchannels;
 930    obt_as.fmt = obt.fmt;
 931    obt_as.endianness = obt.endianness;
 932
 933    audio_pcm_init_info (&hw->info, &obt_as);
 934    hw->samples = obt.samples;
 935
 936    alsa->pcm_buf = audio_calloc (AUDIO_FUNC, hw->samples, 1 << hw->info.shift);
 937    if (!alsa->pcm_buf) {
 938        dolog ("Could not allocate ADC buffer (%d samples, each %d bytes)\n",
 939               hw->samples, 1 << hw->info.shift);
 940        alsa_anal_close1 (&handle);
 941        return -1;
 942    }
 943
 944    alsa->handle = handle;
 945    alsa->pollhlp.conf = conf;
 946    return 0;
 947}
 948
 949static void alsa_fini_in (HWVoiceIn *hw)
 950{
 951    ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
 952
 953    alsa_anal_close (&alsa->handle, &alsa->pollhlp);
 954
 955    g_free(alsa->pcm_buf);
 956    alsa->pcm_buf = NULL;
 957}
 958
 959static int alsa_run_in (HWVoiceIn *hw)
 960{
 961    ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
 962    int hwshift = hw->info.shift;
 963    int i;
 964    int live = audio_pcm_hw_get_live_in (hw);
 965    int dead = hw->samples - live;
 966    int decr;
 967    struct {
 968        int add;
 969        int len;
 970    } bufs[2] = {
 971        { .add = hw->wpos, .len = 0 },
 972        { .add = 0,        .len = 0 }
 973    };
 974    snd_pcm_sframes_t avail;
 975    snd_pcm_uframes_t read_samples = 0;
 976
 977    if (!dead) {
 978        return 0;
 979    }
 980
 981    avail = alsa_get_avail (alsa->handle);
 982    if (avail < 0) {
 983        dolog ("Could not get number of captured frames\n");
 984        return 0;
 985    }
 986
 987    if (!avail) {
 988        snd_pcm_state_t state;
 989
 990        state = snd_pcm_state (alsa->handle);
 991        switch (state) {
 992        case SND_PCM_STATE_PREPARED:
 993            avail = hw->samples;
 994            break;
 995        case SND_PCM_STATE_SUSPENDED:
 996            /* stream is suspended and waiting for an application recovery */
 997            if (alsa_resume (alsa->handle)) {
 998                dolog ("Failed to resume suspended input stream\n");
 999                return 0;
1000            }
1001            trace_alsa_resume_in();
1002            break;
1003        default:
1004            trace_alsa_no_frames(state);
1005            return 0;
1006        }
1007    }
1008
1009    decr = audio_MIN (dead, avail);
1010    if (!decr) {
1011        return 0;
1012    }
1013
1014    if (hw->wpos + decr > hw->samples) {
1015        bufs[0].len = (hw->samples - hw->wpos);
1016        bufs[1].len = (decr - (hw->samples - hw->wpos));
1017    }
1018    else {
1019        bufs[0].len = decr;
1020    }
1021
1022    for (i = 0; i < 2; ++i) {
1023        void *src;
1024        struct st_sample *dst;
1025        snd_pcm_sframes_t nread;
1026        snd_pcm_uframes_t len;
1027
1028        len = bufs[i].len;
1029
1030        src = advance (alsa->pcm_buf, bufs[i].add << hwshift);
1031        dst = hw->conv_buf + bufs[i].add;
1032
1033        while (len) {
1034            nread = snd_pcm_readi (alsa->handle, src, len);
1035
1036            if (nread <= 0) {
1037                switch (nread) {
1038                case 0:
1039                    trace_alsa_read_zero(len);
1040                    goto exit;
1041
1042                case -EPIPE:
1043                    if (alsa_recover (alsa->handle)) {
1044                        alsa_logerr (nread, "Failed to read %ld frames\n", len);
1045                        goto exit;
1046                    }
1047                    trace_alsa_xrun_in();
1048                    continue;
1049
1050                case -EAGAIN:
1051                    goto exit;
1052
1053                default:
1054                    alsa_logerr (
1055                        nread,
1056                        "Failed to read %ld frames from %p\n",
1057                        len,
1058                        src
1059                        );
1060                    goto exit;
1061                }
1062            }
1063
1064            hw->conv (dst, src, nread);
1065
1066            src = advance (src, nread << hwshift);
1067            dst += nread;
1068
1069            read_samples += nread;
1070            len -= nread;
1071        }
1072    }
1073
1074 exit:
1075    hw->wpos = (hw->wpos + read_samples) % hw->samples;
1076    return read_samples;
1077}
1078
1079static int alsa_read (SWVoiceIn *sw, void *buf, int size)
1080{
1081    return audio_pcm_sw_read (sw, buf, size);
1082}
1083
1084static int alsa_ctl_in (HWVoiceIn *hw, int cmd, ...)
1085{
1086    ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
1087
1088    switch (cmd) {
1089    case VOICE_ENABLE:
1090        {
1091            va_list ap;
1092            int poll_mode;
1093
1094            va_start (ap, cmd);
1095            poll_mode = va_arg (ap, int);
1096            va_end (ap);
1097
1098            ldebug ("enabling voice\n");
1099            if (poll_mode && alsa_poll_in (hw)) {
1100                poll_mode = 0;
1101            }
1102            hw->poll_mode = poll_mode;
1103
1104            return alsa_voice_ctl (alsa->handle, "capture", VOICE_CTL_START);
1105        }
1106
1107    case VOICE_DISABLE:
1108        ldebug ("disabling voice\n");
1109        if (hw->poll_mode) {
1110            hw->poll_mode = 0;
1111            alsa_fini_poll (&alsa->pollhlp);
1112        }
1113        return alsa_voice_ctl (alsa->handle, "capture", VOICE_CTL_PAUSE);
1114    }
1115
1116    return -1;
1117}
1118
1119static ALSAConf glob_conf = {
1120    .buffer_size_out = 4096,
1121    .period_size_out = 1024,
1122    .pcm_name_out = "default",
1123    .pcm_name_in = "default",
1124};
1125
1126static void *alsa_audio_init (void)
1127{
1128    ALSAConf *conf = g_malloc(sizeof(ALSAConf));
1129    *conf = glob_conf;
1130    return conf;
1131}
1132
1133static void alsa_audio_fini (void *opaque)
1134{
1135    g_free(opaque);
1136}
1137
1138static struct audio_option alsa_options[] = {
1139    {
1140        .name        = "DAC_SIZE_IN_USEC",
1141        .tag         = AUD_OPT_BOOL,
1142        .valp        = &glob_conf.size_in_usec_out,
1143        .descr       = "DAC period/buffer size in microseconds (otherwise in frames)"
1144    },
1145    {
1146        .name        = "DAC_PERIOD_SIZE",
1147        .tag         = AUD_OPT_INT,
1148        .valp        = &glob_conf.period_size_out,
1149        .descr       = "DAC period size (0 to go with system default)",
1150        .overriddenp = &glob_conf.period_size_out_overridden
1151    },
1152    {
1153        .name        = "DAC_BUFFER_SIZE",
1154        .tag         = AUD_OPT_INT,
1155        .valp        = &glob_conf.buffer_size_out,
1156        .descr       = "DAC buffer size (0 to go with system default)",
1157        .overriddenp = &glob_conf.buffer_size_out_overridden
1158    },
1159    {
1160        .name        = "ADC_SIZE_IN_USEC",
1161        .tag         = AUD_OPT_BOOL,
1162        .valp        = &glob_conf.size_in_usec_in,
1163        .descr       =
1164        "ADC period/buffer size in microseconds (otherwise in frames)"
1165    },
1166    {
1167        .name        = "ADC_PERIOD_SIZE",
1168        .tag         = AUD_OPT_INT,
1169        .valp        = &glob_conf.period_size_in,
1170        .descr       = "ADC period size (0 to go with system default)",
1171        .overriddenp = &glob_conf.period_size_in_overridden
1172    },
1173    {
1174        .name        = "ADC_BUFFER_SIZE",
1175        .tag         = AUD_OPT_INT,
1176        .valp        = &glob_conf.buffer_size_in,
1177        .descr       = "ADC buffer size (0 to go with system default)",
1178        .overriddenp = &glob_conf.buffer_size_in_overridden
1179    },
1180    {
1181        .name        = "THRESHOLD",
1182        .tag         = AUD_OPT_INT,
1183        .valp        = &glob_conf.threshold,
1184        .descr       = "(undocumented)"
1185    },
1186    {
1187        .name        = "DAC_DEV",
1188        .tag         = AUD_OPT_STR,
1189        .valp        = &glob_conf.pcm_name_out,
1190        .descr       = "DAC device name (for instance dmix)"
1191    },
1192    {
1193        .name        = "ADC_DEV",
1194        .tag         = AUD_OPT_STR,
1195        .valp        = &glob_conf.pcm_name_in,
1196        .descr       = "ADC device name"
1197    },
1198    { /* End of list */ }
1199};
1200
1201static struct audio_pcm_ops alsa_pcm_ops = {
1202    .init_out = alsa_init_out,
1203    .fini_out = alsa_fini_out,
1204    .run_out  = alsa_run_out,
1205    .write    = alsa_write,
1206    .ctl_out  = alsa_ctl_out,
1207
1208    .init_in  = alsa_init_in,
1209    .fini_in  = alsa_fini_in,
1210    .run_in   = alsa_run_in,
1211    .read     = alsa_read,
1212    .ctl_in   = alsa_ctl_in,
1213};
1214
1215struct audio_driver alsa_audio_driver = {
1216    .name           = "alsa",
1217    .descr          = "ALSA http://www.alsa-project.org",
1218    .options        = alsa_options,
1219    .init           = alsa_audio_init,
1220    .fini           = alsa_audio_fini,
1221    .pcm_ops        = &alsa_pcm_ops,
1222    .can_be_default = 1,
1223    .max_voices_out = INT_MAX,
1224    .max_voices_in  = INT_MAX,
1225    .voice_size_out = sizeof (ALSAVoiceOut),
1226    .voice_size_in  = sizeof (ALSAVoiceIn)
1227};
1228