drm/rcar-du: Add OF support

Implement support for the R-Car DU DT bindings in the rcar-du DRM
driver.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_encoder.c b/drivers/gpu/drm/rcar-du/rcar_du_encoder.c
index fd152d0..7c0ec95 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_encoder.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_encoder.c
@@ -142,7 +142,8 @@
 int rcar_du_encoder_init(struct rcar_du_device *rcdu,
 			 enum rcar_du_encoder_type type,
 			 enum rcar_du_output output,
-			 const struct rcar_du_encoder_data *data)
+			 const struct rcar_du_encoder_data *data,
+			 struct device_node *np)
 {
 	struct rcar_du_encoder *renc;
 	unsigned int encoder_type;
@@ -189,9 +190,11 @@
 	drm_encoder_helper_add(&renc->encoder, &encoder_helper_funcs);
 
 	switch (encoder_type) {
-	case DRM_MODE_ENCODER_LVDS:
-		return rcar_du_lvds_connector_init(rcdu, renc,
-						   &data->connector.lvds.panel);
+	case DRM_MODE_ENCODER_LVDS: {
+		const struct rcar_du_panel_data *pdata =
+			data ? &data->connector.lvds.panel : NULL;
+		return rcar_du_lvds_connector_init(rcdu, renc, pdata, np);
+	}
 
 	case DRM_MODE_ENCODER_DAC:
 		return rcar_du_vga_connector_init(rcdu, renc);