backlight_device_unregister
backlight_device_unregister(bd);
backlight_device_unregister(dm->backlight_dev[aconnector->bl_idx]);
backlight_device_unregister(panel->backlight.device);
void backlight_device_unregister(struct backlight_device *);
backlight_device_unregister(bd);
backlight_device_unregister(bd);