UART_EXAR_FCTR
exar_write_reg(priv, (offset + UART_EXAR_FCTR), UART_FCTR_EXAR_TRGD);
writeb(UART_FCTR_EXAR_TRGD, p + UART_EXAR_FCTR);
value = readb(p + UART_EXAR_FCTR);
writeb(value, p + UART_EXAR_FCTR);
writeb(UART_FCTR_EXAR_TRGD, p + UART_EXAR_FCTR);
exar_write_reg(priv, (offset + UART_EXAR_FCTR), UART_FCTR_EXAR_TRGD);