diff options
| -rw-r--r-- | audio/out/ao_alsa.c | 45 |
1 files changed, 42 insertions, 3 deletions
diff --git a/audio/out/ao_alsa.c b/audio/out/ao_alsa.c index c7407b0890..af051bed4f 100644 --- a/audio/out/ao_alsa.c +++ b/audio/out/ao_alsa.c @@ -440,7 +440,10 @@ static void uninit(struct ao *ao) alsa_error: ; } -static int init(struct ao *ao) +#define INIT_OK 0 +#define INIT_ERROR -1 +#define INIT_BRAINDEATH -2 +static int init_device(struct ao *ao) { struct priv *p = ao->priv; int err; @@ -621,6 +624,34 @@ static int init(struct ao *ao) MP_WARN(ao, "ALSA channel map conflicts with channel count!\n"); } } else { + // Is it one that contains NA channels? + struct mp_chmap chmap2 = {0}; + for (int c = 0; c < alsa_chmap->channels; c++) { + int alsa_ch = alsa_chmap->pos[c]; + if (alsa_ch != SND_CHMAP_NA) + chmap2.speaker[chmap2.num++] = find_mp_channel(alsa_ch); + } + + if (mp_chmap_is_valid(&chmap2)) { + // Sometimes, ALSA will advertise certain chmaps, but it's not + // possible to set them. This can happen with dmix: as of + // alsa 1.0.28, dmix can do stereo only, but advertises the + // surround chmaps of the underlying device. In this case, + // requesting e.g. 5.1 will fail, but it will still allow + // setting 6 channels. Then it will return something like + // "FL FR NA NA NA NA" as channel map. This means we would + // have to pad stereo output to 6 channels with silence, which + // is way too complicated in the general case. You can't change + // the number of channels to 2 either, because the hw params + // are already set! So just fuck it and reopen the device with + // the chmap "cleaned out" of NA entries. + err = snd_pcm_close(p->alsa); + p->alsa = NULL; + CHECK_ALSA_ERROR("pcm close error"); + ao->channels = chmap2; + return INIT_BRAINDEATH; + } + MP_WARN(ao, "Got unknown channel map from ALSA.\n"); } @@ -675,11 +706,19 @@ static int init(struct ao *ao) p->can_pause = snd_pcm_hw_params_can_pause(alsa_hwparams); - return 0; + return INIT_OK; alsa_error: uninit(ao); - return -1; + return INIT_ERROR; +} + +static int init(struct ao *ao) +{ + int r = init_device(ao); + if (r == INIT_BRAINDEATH) + r = init_device(ao); // retry with normalized channel layout + return r == INIT_OK ? 0 : -1; } static void drain(struct ao *ao) |