diff options
Diffstat (limited to 'include/sound/pcm.h')
| -rw-r--r-- | include/sound/pcm.h | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/include/sound/pcm.h b/include/sound/pcm.h index cdca2ab..669c85a 100644 --- a/include/sound/pcm.h +++ b/include/sound/pcm.h @@ -437,6 +437,7 @@ struct snd_pcm_str { struct snd_info_entry *proc_xrun_debug_entry; #endif #endif + struct snd_kcontrol *chmap_kctl; /* channel-mapping controls */ }; struct snd_pcm { @@ -1086,4 +1087,51 @@ static inline const char *snd_pcm_stream_str(struct snd_pcm_substream *substream return "Capture"; } +/* + * PCM channel-mapping control API + */ +/* array element of channel maps */ +struct snd_pcm_chmap_elem { + unsigned char channels; + unsigned char map[15]; +}; + +/* channel map information; retrieved via snd_kcontrol_chip() */ +struct snd_pcm_chmap { + struct snd_pcm *pcm; /* assigned PCM instance */ + int stream; /* PLAYBACK or CAPTURE */ + struct snd_kcontrol *kctl; + const struct snd_pcm_chmap_elem *chmap; + unsigned int max_channels; + unsigned int channel_mask; /* optional: active channels bitmask */ + void *private_data; /* optional: private data pointer */ +}; + +/* get the PCM substream assigned to the given chmap info */ +static inline struct snd_pcm_substream * +snd_pcm_chmap_substream(struct snd_pcm_chmap *info, unsigned int idx) +{ + struct snd_pcm_substream *s; + for (s = info->pcm->streams[info->stream].substream; s; s = s->next) + if (s->number == idx) + return s; + return NULL; +} + +/* ALSA-standard channel maps (RL/RR prior to C/LFE) */ +extern const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[]; +/* Other world's standard channel maps (C/LFE prior to RL/RR) */ +extern const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[]; + +/* bit masks to be passed to snd_pcm_chmap.channel_mask field */ +#define SND_PCM_CHMAP_MASK_24 ((1U << 2) | (1U << 4)) +#define SND_PCM_CHMAP_MASK_246 (SND_PCM_CHMAP_MASK_24 | (1U << 6)) +#define SND_PCM_CHMAP_MASK_2468 (SND_PCM_CHMAP_MASK_246 | (1U << 8)) + +int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream, + const struct snd_pcm_chmap_elem *chmap, + int max_channels, + unsigned long private_value, + struct snd_pcm_chmap **info_ret); + #endif /* __SOUND_PCM_H */ |
