diff --git a/drivers/serial/amba-pl010.c b/drivers/serial/amba-pl010.c
index 50441ffe8e3856592dbfdae368e9891b64078d50..2904aa044126dbc49729caacbcb3d236da900bc6 100644
--- a/drivers/serial/amba-pl010.c
+++ b/drivers/serial/amba-pl010.c
@@ -472,14 +472,9 @@ pl010_set_termios(struct uart_port *port, struct ktermios *termios,
 	spin_unlock_irqrestore(&uap->port.lock, flags);
 }
 
-static void pl010_set_ldisc(struct uart_port *port)
+static void pl010_set_ldisc(struct uart_port *port, int new)
 {
-	int line = port->line;
-
-	if (line >= port->state->port.tty->driver->num)
-		return;
-
-	if (port->state->port.tty->ldisc->ops->num == N_PPS) {
+	if (new == N_PPS) {
 		port->flags |= UPF_HARDPPS_CD;
 		pl010_enable_ms(port);
 	} else