From: Luca Ceresoli Date: Fri, 9 May 2025 13:53:46 +0000 (+0200) Subject: drm/bridge: add devm_drm_put_bridge() X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=5164553d739ef45b2c69c8cfe88b9ef26c9a0035;p=thirdparty%2Flinux.git drm/bridge: add devm_drm_put_bridge() Bridges obtained via devm_drm_bridge_alloc(dev, ...) will be put when the requesting device (@dev) is removed. However drivers which obtained them may need to put the obtained reference explicitly. One such case is if they bind the devm removal action to a different device than the one implemented by the driver itself and which might be removed at a different time, such as bridge/panel.c. Add devm_drm_put_bridge() to manually release a devm-obtained bridge in such cases. This function is considered only a temporary workaround until the panel bridge is reworked and should be removed afterwards. Acked-by: Maxime Ripard Link: https://lore.kernel.org/r/20250509-drm-bridge-convert-to-alloc-api-v3-20-b8bc1f16d7aa@bootlin.com Signed-off-by: Luca Ceresoli --- diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index b4c89ec01998b..d0e81639927a7 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -1392,6 +1392,23 @@ struct drm_bridge *of_drm_find_bridge(struct device_node *np) EXPORT_SYMBOL(of_drm_find_bridge); #endif +/** + * devm_drm_put_bridge - Release a bridge reference obtained via devm + * @dev: device that got the bridge via devm + * @bridge: pointer to a struct drm_bridge obtained via devm + * + * Same as drm_bridge_put() for bridge pointers obtained via devm functions + * such as devm_drm_bridge_alloc(). + * + * This function is a temporary workaround and MUST NOT be used. Manual + * handling of bridge lifetime is inherently unsafe. + */ +void devm_drm_put_bridge(struct device *dev, struct drm_bridge *bridge) +{ + devm_release_action(dev, drm_bridge_put_void, bridge); +} +EXPORT_SYMBOL(devm_drm_put_bridge); + static void drm_bridge_debugfs_show_bridge(struct drm_printer *p, struct drm_bridge *bridge, unsigned int idx) diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h index cc9f7df38102e..464da28f9134f 100644 --- a/include/drm/drm_bridge.h +++ b/include/drm/drm_bridge.h @@ -1311,6 +1311,8 @@ static inline struct drm_bridge *devm_drm_of_get_bridge(struct device *dev, return ERR_PTR(-ENODEV); } +static inline void devm_drm_put_bridge(struct device *dev, struct drm_bridge *bridge) {} + static inline struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm, struct device_node *node, u32 port, @@ -1320,6 +1322,8 @@ static inline struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm, } #endif +void devm_drm_put_bridge(struct device *dev, struct drm_bridge *bridge); + void drm_bridge_debugfs_params(struct dentry *root); void drm_bridge_debugfs_encoder_params(struct dentry *root, struct drm_encoder *encoder);