if (err) return err; return count;
put_device(dev); put_bus(bus); return err;
static ssize_t driver_unbind(struct device_driver *drv,			     const char *buf, size_t count){	struct bus_type *bus = get_bus(drv->bus);	struct device *dev;	int err = -ENODEV;	dev = bus_find_device(bus, NULL, (void *)buf, driver_helper);	if ((dev) &&	    (dev->driver == drv)) {		device_release_driver(dev);		err = count;	}	if (err)		return err;	return count;}