serial: 8250: Expose set_ldisc function

Expose set_ldisc() function so that it can be overridden with a
platform specific implementation.

Signed-off-by: Ed Blake <ed.blake@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
index 04185e03..61fbb44 100644
--- a/include/linux/serial_8250.h
+++ b/include/linux/serial_8250.h
@@ -36,6 +36,8 @@ struct plat_serial8250_port {
 	void		(*set_termios)(struct uart_port *,
 			               struct ktermios *new,
 			               struct ktermios *old);
+	void		(*set_ldisc)(struct uart_port *,
+				     struct ktermios *);
 	unsigned int	(*get_mctrl)(struct uart_port *);
 	int		(*handle_irq)(struct uart_port *);
 	void		(*pm)(struct uart_port *, unsigned int state,
@@ -149,6 +151,8 @@ extern int early_serial8250_setup(struct earlycon_device *device,
 					 const char *options);
 extern void serial8250_do_set_termios(struct uart_port *port,
 		struct ktermios *termios, struct ktermios *old);
+extern void serial8250_do_set_ldisc(struct uart_port *port,
+				    struct ktermios *termios);
 extern unsigned int serial8250_do_get_mctrl(struct uart_port *port);
 extern int serial8250_do_startup(struct uart_port *port);
 extern void serial8250_do_shutdown(struct uart_port *port);