device_match_devt
EXPORT_SYMBOL_GPL(device_match_devt);
int device_match_devt(struct device *dev, const void *pdevt);
return bus_find_device(bus, NULL, &devt, device_match_devt);
return class_find_device(class, NULL, &devt, device_match_devt);
return driver_find_device(drv, NULL, &devt, device_match_devt);