USB: gadget: Hangup tty on g_serial disconnect

On USB cable disconnect g_serial doesn't hangup the port tty,
which results in an endless read on the tty device. With the
following patch the read and select behave correctly when
the cable is unplugged.

Tested on at91rm9200

Signed-off-by: Savin Zlobec <savin@epiko.si>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 1 insertions, 2 deletions

diff --git a/drivers/usb/gadget/serial.c b/drivers/usb/gadget/serial.c
index f5c3896b1d95..433b3f44f42e 100644
--- a/drivers/usb/gadget/serial.c
+++ b/drivers/usb/gadget/serial.c
@@ -2163,8 +2163,7 @@ static void gs_free_ports(struct gs_dev *dev)
                                 port->port_dev = NULL;
                                 wake_up_interruptible(&port->port_write_wait);
                                 if (port->port_tty) {
-                                        wake_up_interruptible(&port->port_tty->read_wait);
-                                        wake_up_interruptible(&port->port_tty->write_wait);
+                                        tty_hangup(port->port_tty);
                                 }
                                 spin_unlock_irqrestore(&port->port_lock, flags);
                         } else {