code: func (kl *Kubelet) getPodVolumeDeviceDir(podUID types.UID, pluginName string) string {
  	return filepath.Join(kl.getPodVolumeDevicesDir(podUID), pluginName)
  }
docs: // getPodVolumeDeviceDir returns the full path to the directory which represents the
  // named plugin for specified pod. This directory may not exist if the pod does not exist.