TI_MCR_RTS
| ((mcr & TI_MCR_RTS) ? TIOCM_RTS : 0)
mcr |= TI_MCR_RTS;
mcr &= ~TI_MCR_RTS;
TI_MCR_RTS | TI_MCR_DTR | TI_MCR_LOOP, mcr);
tport->tp_shadow_mcr |= (TI_MCR_RTS | TI_MCR_DTR);
mcr &= ~(TI_MCR_DTR | TI_MCR_RTS);