drm/mediatek: ovl_adaptor: Fix probe device leaks

Make sure to drop the references taken to the component devices by
of_find_device_by_node() during probe on probe failure (e.g. probe
deferral) and on driver unbind.

Fixes: 453c3364632a ("drm/mediatek: Add ovl_adaptor support for MT8195")
Cc: stable@vger.kernel.org	# 6.4
Cc: Nancy.Lin <nancy.lin@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/20250923152340.18234-6-johan@kernel.org/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c
index fe97bb97e004ad5bc7e3db31edf1f44d4377ba08..c0af3e3b51d554333494e682b2bc581958aea24b 100644 (file)
--- a/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c
@@ -527,6 +527,13 @@ bool mtk_ovl_adaptor_is_comp_present(struct device_node *node)
               type == OVL_ADAPTOR_TYPE_PADDING;
 }
 
+static void ovl_adaptor_put_device(void *_dev)
+{
+       struct device *dev = _dev;
+
+       put_device(dev);
+}
+
 static int ovl_adaptor_comp_init(struct device *dev, struct component_match **match)
 {
        struct mtk_disp_ovl_adaptor *priv = dev_get_drvdata(dev);
@@ -560,6 +567,11 @@ static int ovl_adaptor_comp_init(struct device *dev, struct component_match **ma
                if (!comp_pdev)
                        return -EPROBE_DEFER;
 
+               ret = devm_add_action_or_reset(dev, ovl_adaptor_put_device,
+                                              &comp_pdev->dev);
+               if (ret)
+                       return ret;
+
                priv->ovl_adaptor_comp[id] = &comp_pdev->dev;
 
                drm_of_component_match_add(dev, match, component_compare_of, node);