SCI_TEND
#define SCI_TDxE_CLEAR (u32)(~(SCI_RESERVED | SCI_TEND | SCI_TDRE))
#define SCxSR_TEND(port) (((port)->type == PORT_SCI) ? SCI_TEND : SCIF_TEND)
.poll_sent_bits = SCI_TDRE | SCI_TEND