diff --git a/drivers/serial/bfin_5xx.c b/drivers/serial/bfin_5xx.c
index 9d85437..efcd443 100644
--- a/drivers/serial/bfin_5xx.c
+++ b/drivers/serial/bfin_5xx.c
@@ -817,7 +817,7 @@
 	if (line >= port->info->port.tty->driver->num)
 		return;
 
-	switch (port->info->port.tty->ldisc.num) {
+	switch (port->info->port.tty->termios->c_line) {
 	case N_IRDA:
 		val = UART_GET_GCTL(&bfin_serial_ports[line]);
 		val |= (IREN | RPOLC);