drm/mediatek: Separate getting larb device to a function

To make the code cleaner, separate getting larb device to
a function.
Signed-off-by: NCK Hu <ck.hu@mediatek.com>
Signed-off-by: NChun-Kuang Hu <chunkuang.hu@kernel.org>

drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c

@@ -465,19 +465,41 @@ unsigned int mtk_drm_find_possible_crtc_by_comp(struct drm_device *drm,
 	return ret;
 }
 
+static int mtk_ddp_get_larb_dev(struct device_node *node, struct mtk_ddp_comp *comp,
+				struct device *dev)
+{
+	struct device_node *larb_node;
+	struct platform_device *larb_pdev;
+
+	larb_node = of_parse_phandle(node, "mediatek,larb", 0);
+	if (!larb_node) {
+		dev_err(dev, "Missing mediadek,larb phandle in %pOF node\n", node);
+		return -EINVAL;
+	}
+
+	larb_pdev = of_find_device_by_node(larb_node);
+	if (!larb_pdev) {
+		dev_warn(dev, "Waiting for larb device %pOF\n", larb_node);
+		of_node_put(larb_node);
+		return -EPROBE_DEFER;
+	}
+	of_node_put(larb_node);
+	comp->larb_dev = &larb_pdev->dev;
+
+	return 0;
+}
+
 int mtk_ddp_comp_init(struct device_node *node, struct mtk_ddp_comp *comp,
 		      enum mtk_ddp_comp_id comp_id, const struct mtk_ddp_comp_funcs *funcs)
 {
 	struct platform_device *comp_pdev;
 	struct device *dev;
 	enum mtk_ddp_comp_type type;
-	struct device_node *larb_node;
-	struct platform_device *larb_pdev;
 #if IS_REACHABLE(CONFIG_MTK_CMDQ)
 	struct resource res;
 	struct cmdq_client_reg cmdq_reg;
-	int ret;
 #endif
+	int ret;
 
 	if (comp_id < 0 || comp_id >= DDP_COMPONENT_ID_MAX)
 		return -EINVAL;
@@ -529,30 +551,15 @@ int mtk_ddp_comp_init(struct device_node *node, struct mtk_ddp_comp *comp,
 #endif
 
 	/* Only DMA capable components need the LARB property */
-	comp->larb_dev = NULL;
-	if (type != MTK_DISP_OVL &&
-	    type != MTK_DISP_OVL_2L &&
-	    type != MTK_DISP_RDMA &&
-	    type != MTK_DISP_WDMA)
-		return 0;
-
-	larb_node = of_parse_phandle(node, "mediatek,larb", 0);
-	if (!larb_node) {
-		dev_err(dev,
-			"Missing mediadek,larb phandle in %pOF node\n", node);
-		return -EINVAL;
+	if (type == MTK_DISP_OVL ||
+	    type == MTK_DISP_OVL_2L ||
+	    type == MTK_DISP_RDMA ||
+	    type == MTK_DISP_WDMA) {
+		ret = mtk_ddp_get_larb_dev(node, comp, dev);
+		if (ret)
+			return ret;
 	}
 
-	larb_pdev = of_find_device_by_node(larb_node);
-	if (!larb_pdev) {
-		dev_warn(dev, "Waiting for larb device %pOF\n", larb_node);
-		of_node_put(larb_node);
-		return -EPROBE_DEFER;
-	}
-	of_node_put(larb_node);
-
-	comp->larb_dev = &larb_pdev->dev;
-
 	return 0;
 }