diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index bc8ed4b..355148d 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -2404,14 +2404,9 @@
 }
 
 static void
-serial8250_set_ldisc(struct uart_port *port)
+serial8250_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;
 		serial8250_enable_ms(port);
 	} else