drm/mediatek: Fix probe resource leaks

commit 07c7c64 upstream.

Make sure to unmap and release the component iomap and clock on probe
failure (e.g. probe deferral) and on driver unbind.

Note that unlike of_iomap(), devm_of_iomap() also checks whether the
region is already mapped.

Fixes: 119f517 ("drm/mediatek: Add DRM Driver for Mediatek SoC MT8173.")
Cc: stable@vger.kernel.org	# 4.7
Cc: CK Hu <ck.hu@mediatek.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20250923152340.18234-2-johan@kernel.org/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: jhovold

drivers/gpu/drm/mediatek/mtk_ddp_comp.c

@@ -621,15 +621,20 @@ int mtk_find_possible_crtcs(struct drm_device *drm, struct device *dev)
 	return ret;
 }
 
-int mtk_ddp_comp_init(struct device_node *node, struct mtk_ddp_comp *comp,
+static void mtk_ddp_comp_clk_put(void *_clk)
+{
+	struct clk *clk = _clk;
+
+	clk_put(clk);
+}
+
+int mtk_ddp_comp_init(struct device *dev, struct device_node *node, struct mtk_ddp_comp *comp,
 		      unsigned int comp_id)
 {
 	struct platform_device *comp_pdev;
 	enum mtk_ddp_comp_type type;
 	struct mtk_ddp_comp_dev *priv;
-#if IS_REACHABLE(CONFIG_MTK_CMDQ)
 	int ret;
-#endif
 
 	if (comp_id >= DDP_COMPONENT_DRM_ID_MAX)
 		return -EINVAL;
@@ -670,11 +675,18 @@ int mtk_ddp_comp_init(struct device_node *node, struct mtk_ddp_comp *comp,
 	if (!priv)
 		return -ENOMEM;
 
-	priv->regs = of_iomap(node, 0);
+	priv->regs = devm_of_iomap(dev, node, 0, NULL);
+	if (IS_ERR(priv->regs))
+		return PTR_ERR(priv->regs);
+
 	priv->clk = of_clk_get(node, 0);
 	if (IS_ERR(priv->clk))
 		return PTR_ERR(priv->clk);
 
+	ret = devm_add_action_or_reset(dev, mtk_ddp_comp_clk_put, priv->clk);
+	if (ret)
+		return ret;
+
 #if IS_REACHABLE(CONFIG_MTK_CMDQ)
 	ret = cmdq_dev_get_client_reg(comp->dev, &priv->cmdq_reg, 0);
 	if (ret)

drivers/gpu/drm/mediatek/mtk_ddp_comp.h

@@ -350,7 +350,7 @@ static inline void mtk_ddp_comp_encoder_index_set(struct mtk_ddp_comp *comp)
 int mtk_ddp_comp_get_id(struct device_node *node,
 			enum mtk_ddp_comp_type comp_type);
 int mtk_find_possible_crtcs(struct drm_device *drm, struct device *dev);
-int mtk_ddp_comp_init(struct device_node *comp_node, struct mtk_ddp_comp *comp,
+int mtk_ddp_comp_init(struct device *dev, struct device_node *comp_node, struct mtk_ddp_comp *comp,
 		      unsigned int comp_id);
 enum mtk_ddp_comp_type mtk_ddp_comp_get_type(unsigned int comp_id);
 void mtk_ddp_write(struct cmdq_pkt *cmdq_pkt, unsigned int value,

drivers/gpu/drm/mediatek/mtk_drm_drv.c

@@ -1123,7 +1123,7 @@ static int mtk_drm_probe(struct platform_device *pdev)
 							    (void *)private->mmsys_dev,
 							    sizeof(*private->mmsys_dev));
 		private->ddp_comp[DDP_COMPONENT_DRM_OVL_ADAPTOR].dev = &ovl_adaptor->dev;
-		mtk_ddp_comp_init(NULL, &private->ddp_comp[DDP_COMPONENT_DRM_OVL_ADAPTOR],
+		mtk_ddp_comp_init(dev, NULL, &private->ddp_comp[DDP_COMPONENT_DRM_OVL_ADAPTOR],
 				  DDP_COMPONENT_DRM_OVL_ADAPTOR);
 		component_match_add(dev, &match, compare_dev, &ovl_adaptor->dev);
 	}
@@ -1189,7 +1189,7 @@ static int mtk_drm_probe(struct platform_device *pdev)
 						   node);
 		}
 
-		ret = mtk_ddp_comp_init(node, &private->ddp_comp[comp_id], comp_id);
+		ret = mtk_ddp_comp_init(dev, node, &private->ddp_comp[comp_id], comp_id);
 		if (ret) {
 			of_node_put(node);
 			goto err_node;