USB: visor: fix trivial accounting bug in visor driver

usb:usbserial:visor: fix accounting in error case

data not pushed to the tty layer due to an error mustn't be counted

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c
index 1aa5d20..8e2d6dd 100644 (file)
--- a/drivers/usb/serial/visor.c
+++ b/drivers/usb/serial/visor.c
@@ -513,7 +513,8 @@ static void visor_read_bulk_callback(struct urb *urb)
                        tty_kref_put(tty);
                }
                spin_lock(&priv->lock);
-               priv->bytes_in += available_room;
+               if (tty)
+                       priv->bytes_in += available_room;
 
        } else {
                spin_lock(&priv->lock);