serial: core: Perform RTS signalling before soft flow ctrl

When throttling, time is of the essence; try RTS signalling before
soft flow control, which will take longer.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/serial_core.c

@@ -641,11 +641,11 @@ static void uart_throttle(struct tty_struct *tty)
 		mask &= ~port->status;
 	}
 
-	if (mask & UPSTAT_AUTOXOFF)
-		uart_send_xchar(tty, STOP_CHAR(tty));
-
 	if (mask & UPSTAT_AUTORTS)
 		uart_clear_mctrl(port, TIOCM_RTS);
+
+	if (mask & UPSTAT_AUTOXOFF)
+		uart_send_xchar(tty, STOP_CHAR(tty));
 }
 
 static void uart_unthrottle(struct tty_struct *tty)
@@ -664,11 +664,11 @@ static void uart_unthrottle(struct tty_struct *tty)
 		mask &= ~port->status;
 	}
 
-	if (mask & UPSTAT_AUTOXOFF)
-		uart_send_xchar(tty, START_CHAR(tty));
-
 	if (mask & UPSTAT_AUTORTS)
 		uart_set_mctrl(port, TIOCM_RTS);
+
+	if (mask & UPSTAT_AUTOXOFF)
+		uart_send_xchar(tty, START_CHAR(tty));
 }
 
 static void uart_get_info(struct tty_port *port, struct serial_struct *retinfo)