USB: serial: remove generic disconnect callback

Remove the now empty generic disconnect callback and make the disconnect
callback non-mandatory.
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/serial/generic.c

@@ -45,7 +45,6 @@ struct usb_serial_driver usb_serial_generic_device = {
 	},
 	.id_table =		generic_device_ids,
 	.num_ports =		1,
-	.disconnect =		usb_serial_generic_disconnect,
 	.release =		usb_serial_generic_release,
 	.throttle =		usb_serial_generic_throttle,
 	.unthrottle =		usb_serial_generic_unthrottle,
@@ -500,11 +499,6 @@ int usb_serial_generic_resume(struct usb_serial *serial)
 }
 EXPORT_SYMBOL_GPL(usb_serial_generic_resume);
 
-void usb_serial_generic_disconnect(struct usb_serial *serial)
-{
-}
-EXPORT_SYMBOL_GPL(usb_serial_generic_disconnect);
-
 void usb_serial_generic_release(struct usb_serial *serial)
 {
 }

drivers/usb/serial/usb-serial.c

@@ -1095,7 +1095,8 @@ static void usb_serial_disconnect(struct usb_interface *interface)
 				device_del(&port->dev);
 		}
 	}
-	serial->type->disconnect(serial);
+	if (serial->type->disconnect)
+		serial->type->disconnect(serial);
 
 	/* let the last holder of this object cause it to be cleaned up */
 	usb_serial_put(serial);
@@ -1304,7 +1305,6 @@ static void fixup_generic(struct usb_serial_driver *device)
 	set_to_generic_if_null(device, chars_in_buffer);
 	set_to_generic_if_null(device, read_bulk_callback);
 	set_to_generic_if_null(device, write_bulk_callback);
-	set_to_generic_if_null(device, disconnect);
 	set_to_generic_if_null(device, release);
 	set_to_generic_if_null(device, process_read_urb);
 	set_to_generic_if_null(device, prepare_write_buffer);

include/linux/usb/serial.h

@@ -329,7 +329,6 @@ extern void usb_serial_generic_read_bulk_callback(struct urb *urb);
 extern void usb_serial_generic_write_bulk_callback(struct urb *urb);
 extern void usb_serial_generic_throttle(struct tty_struct *tty);
 extern void usb_serial_generic_unthrottle(struct tty_struct *tty);
-extern void usb_serial_generic_disconnect(struct usb_serial *serial);
 extern void usb_serial_generic_release(struct usb_serial *serial);
 extern int usb_serial_generic_register(void);
 extern void usb_serial_generic_deregister(void);