/* This function is used to send a high-priority XON/XOFF character to the device  */
static void rs_send_xchar(struct tty_struct *tty, char ch)
/* This function is used to send a high-priority XON/XOFF character to the device  */
static void rs_send_xchar(struct tty_struct *tty, char ch)
{
	struct async_struct *info = tty->driver_data;
        unsigned long flags;
	if (serial_paranoia_check(info, tty->name, "rs_send_char"))
		return;
	info->x_char = ch;
	if (ch) {
	        local_irq_save(flags);
		if(!(custom.intenar & IF_TBE)) {
		    custom.intena = IF_SETCLR | IF_TBE;
		    mb();
		    custom.intreq = IF_SETCLR | IF_TBE;
		    mb();
		}
		local_irq_restore(flags);
		info->IER |= UART_IER_THRI;
	}
}