diff --git a/[refs] b/[refs]
index 6e22da6c1653..13b5ddd67524 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: dc77f161aa5e81ddaf38390094c4f2ca3814e6b1
+refs/heads/master: 7ed63d5eb4c0de0321f5c0a7328e132a78f9fafe
diff --git a/trunk/drivers/serial/amba-pl010.c b/trunk/drivers/serial/amba-pl010.c
index 429a8ae86933..e4b3c2c88bb6 100644
--- a/trunk/drivers/serial/amba-pl010.c
+++ b/trunk/drivers/serial/amba-pl010.c
@@ -471,6 +471,20 @@ 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)
+{
+	int line = port->line;
+
+	if (line >= port->state->port.tty->driver->num)
+		return;
+
+	if (port->state->port.tty->ldisc->ops->num == N_PPS) {
+		port->flags |= UPF_HARDPPS_CD;
+		pl010_enable_ms(port);
+	} else
+		port->flags &= ~UPF_HARDPPS_CD;
+}
+
 static const char *pl010_type(struct uart_port *port)
 {
 	return port->type == PORT_AMBA ? "AMBA" : NULL;
@@ -531,6 +545,7 @@ static struct uart_ops amba_pl010_pops = {
 	.startup	= pl010_startup,
 	.shutdown	= pl010_shutdown,
 	.set_termios	= pl010_set_termios,
+	.set_ldisc	= pl010_set_ldisc,
 	.type		= pl010_type,
 	.release_port	= pl010_release_port,
 	.request_port	= pl010_request_port,