USB: quatech2: only write to the tty if the port is open.

The commit 2e124b4 removed the checks that prevented qt2_process_read_urb() from trying to put chars into ttys that weren't actually opened. This resulted in 'tty is NULL' warnings from flush_to_ldisc() when the device was used. The devices use just one read urb for all ports. As a result qt2_process_read_urb() may be called with the current port set to a port number that has not been opened. Add a check if the port is open before calling tty_flip_buffer_push(). Signed-off-by: Bill Pemberton <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
akeromi · Mar 13, 2013 · 27b351c · 27b351c
1 parent 3f8bc5e
commit 27b351c
Showing 1 changed file with 5 additions and 2 deletions.
diff --git a/drivers/usb/serial/quatech2.c b/drivers/usb/serial/quatech2.c
@@ -661,7 +661,9 @@ void qt2_process_read_urb(struct urb *urb)
 						 __func__);
 					break;
 				}
-				tty_flip_buffer_push(&port->port);
+
+				if (port_priv->is_open)
+					tty_flip_buffer_push(&port->port);
 
 				newport = *(ch + 3);
 
@@ -704,7 +706,8 @@ void qt2_process_read_urb(struct urb *urb)
 		tty_insert_flip_string(&port->port, ch, 1);
 	}
 
-	tty_flip_buffer_push(&port->port);
+	if (port_priv->is_open)
+		tty_flip_buffer_push(&port->port);
 }
 
 static void qt2_write_bulk_callback(struct urb *urb)