tty_port: Add a port level carrier detect operation

[linux-2.6-omap-h63xx.git] / drivers / char / tty_port.c

diff --git a/drivers/char/tty_port.c b/drivers/char/tty_port.c
index c8f8024cb40e5d6b4fcc6ad1a8f4408104e9f81a..f54e40cbf02352113485c2f9c0ac9a4baf47ba74 100644 (file)
--- a/drivers/char/tty_port.c
+++ b/drivers/char/tty_port.c
@@ -94,3 +94,20 @@ void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty)
        spin_unlock_irqrestore(&port->lock, flags);
 }
 EXPORT_SYMBOL(tty_port_tty_set);
+
+/**
+ *     tty_port_carrier_raised -       carrier raised check
+ *     @port: tty port
+ *
+ *     Wrapper for the carrier detect logic. For the moment this is used
+ *     to hide some internal details. This will eventually become entirely
+ *     internal to the tty port.
+ */
+
+int tty_port_carrier_raised(struct tty_port *port)
+{
+       if (port->ops->carrier_raised == NULL)
+               return 1;
+       return port->ops->carrier_raised(port);
+}
+EXPORT_SYMBOL(tty_port_carrier_raised);