drm/mediatek: Fix probe resource leaks

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: 119f5173628a ("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>

3 files changed, 19 insertions, 7 deletions

diff --git a/drivers/gpu/drm/mediatek/mtk_ddp_comp.c b/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
index ac6620e10262..0264017806ad 100644
--- a/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
+++ b/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)
diff --git a/drivers/gpu/drm/mediatek/mtk_ddp_comp.h b/drivers/gpu/drm/mediatek/mtk_ddp_comp.h
index 7289b3dcf22f..3f3d43f4330d 100644
--- a/drivers/gpu/drm/mediatek/mtk_ddp_comp.h
+++ b/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,
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
index eb5537f0ac90..384b0510272c 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
@@ -1133,7 +1133,7 @@ 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);
 	}
@@ -1199,7 +1199,7 @@ 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;