if c.csiClient == nil {
		c.csiClient, err = newCsiDriverClient(csiDriverName(csiSource.Driver))
		if err != nil {
			// Treat the absence of the CSI driver as a transient error
			// See https://github.com/kubernetes/kubernetes/issues/120268
			return volumetypes.NewTransientOperationFailure(log("attacher.MountDevice failed to create newCsiDriverClient: %v", err))
		}
	}
	csi := c.csiClient

	csiSource, err := getCSISourceFromSpec(resizeOptions.VolumeSpec)
	if err != nil {
		return false, errors.New(log("Expander.NodeExpand failed to get CSI persistent source: %v", err))
	}

	csClient, err := newCsiDriverClient(csiDriverName(csiSource.Driver))
	if err != nil {
		// Treat the absence of the CSI driver as a transient error
		// See https://github.com/kubernetes/kubernetes/issues/120268

// connection set up. It also returns a closer which must be called to close
// the gRPC connection when the NodeClient is not used anymore.
// This is the default implementation for the nodeV1ClientCreator, used in
// newCsiDriverClient.
func newV1NodeClient(addr csiAddr, metricsManager *MetricsManager) (nodeClient csipbv1.NodeClient, closer io.Closer, err error) {
	var conn *grpc.ClientConn
	conn, err = newGrpcConn(addr, metricsManager)

	csiDrivers.Set(pluginName, Driver{
		endpoint:                endpoint,
		highestSupportedVersion: highestSupportedVersion,
	})

	// Get node info from the driver.
	csi, err := newCsiDriverClient(csiDriverName(pluginName))
	if err != nil {
		return err
	}

	var timeout time.Duration
	if pluginClientTimeout == nil {
		timeout = csiTimeout
	} else {
		timeout = *pluginClientTimeout
	}