def METHOD_NAME(self):
    """
    In init process, find valid watchdog device
    """
    self._set_watchdog_info()
    self._set_input()
    # self._input is a device name
    if self._valid_device(self._input):
        self._watchdog_device_name = self._input
        return
    # self._input is invalid, exit
    if not invokerc("modinfo {}".format(self._input)):
        utils.fatal("Should provide valid watchdog device or driver name by -w option")
    # self._input is a driver name, load it if it was unloaded
    if not self._driver_is_loaded(self._input):
        self._load_watchdog_driver(self._input)
        self._set_watchdog_info()
    # self._input is a loaded driver name, find corresponding device name
    res = self._get_device_through_driver(self._input)
    if res:
        self._watchdog_device_name = res
        return