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. |