cdc-acm: ensure that termios get set when the port is activated

The driver wasn't properly configuring the hardware for the current
termios settings under all conditions.  Ensure that termios are
written to the device when the port is activated.
Signed-off-by: Jim Paris <jim@jtan.com>
Reviewed-by: Johan Hovold <johan@kernel.org>
Acked-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/class/cdc-acm.c

@@ -60,6 +60,9 @@ static struct acm *acm_table[ACM_TTY_MINORS];
 
 static DEFINE_MUTEX(acm_table_lock);
 
+static void acm_tty_set_termios(struct tty_struct *tty,
+				struct ktermios *termios_old);
+
 /*
  * acm_table accessors
  */
@@ -554,6 +557,8 @@ static int acm_port_activate(struct tty_port *port, struct tty_struct *tty)
 		goto error_submit_urb;
 	}
 
+	acm_tty_set_termios(tty, NULL);
+
 	/*
 	 * Unthrottle device in case the TTY was closed while throttled.
 	 */