Fills the setup structure with data about the PCM channel settings selected by handle. The channel member specifies the direction. Other members are read-only. Function returns zero if successful, otherwise it returns an error code.
typedef struct snd_pcm_channel_setup { int channel; int mode; snd_pcm_format_t format; snd_pcm_digital_t digital; union { struct { int queue_size; } stream; struct { int frag_size; int frags; int frags_min; int frags_max; } block; } buf; short msbits_per_sample; short pad1; char reserved[60]; } snd_pcm_channel_setup_t;
Member | Description |
---|---|
channel | Specifies channel (direction). Can be SND_PCM_CHANNEL_PLAYBACK or SND_PCM_CHANNEL_CAPTURE. |
mode | Shows channel mode. Can be SND_PCM_MODE_STREAM or SND_PCM_MODE_BLOCK. |
format | Shows the used format. Especially rate member may differ from requested one. |
digital | Shows the used digital settings. |
queue_size | Shows the real queue size (may differ from requested one). |
frag_size | Shows the real fragment size (may differ from requested one). |
frags | Shows the count of fragments. |
frags_min | Capture: Shows the minimum filled fragments to allow wakeup. Playback: Shows the minimum free fragments to allow wakeup. |
frags_max | Playback: Specifies the maximum filled fragments to allow wakeup. Value also specifies the maximum used fragments plus one. |
msbits_per_sample | Shows how many most significant bits are physically used. |