SPDIF_UBITS_SIZE
size = SPDIF_UBITS_SIZE;
unsigned char subcode[2 * SPDIF_UBITS_SIZE];
int idx = (ctrl->ready_buf - 1) * SPDIF_UBITS_SIZE;
&ctrl->subcode[idx], SPDIF_UBITS_SIZE);
#define SPDIF_QSUB_SIZE (SPDIF_UBITS_SIZE / 8)