From e5ca263508f7e9d2cf711edf3258d11ca087885c Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Sat, 17 Feb 2024 16:02:24 +0100 Subject: drm/bridge: aux-hpd: separate allocation and registration Combining allocation and registration is an anti-pattern that should be avoided. Add two new functions for allocating and registering an dp-hpd bridge with a proper 'devm' prefix so that it is clear that these are device managed interfaces. devm_drm_dp_hpd_bridge_alloc() devm_drm_dp_hpd_bridge_add() The new interface will be used to fix a use-after-free bug in the Qualcomm PMIC GLINK driver and may prevent similar issues from being introduced elsewhere. The existing drm_dp_hpd_bridge_register() is reimplemented using the above and left in place for now. Signed-off-by: Johan Hovold Reviewed-by: Bjorn Andersson Reviewed-by: Dmitry Baryshkov Signed-off-by: Dmitry Baryshkov Link: https://patchwork.freedesktop.org/patch/msgid/20240217150228.5788-3-johan+linaro@kernel.org --- include/drm/bridge/aux-bridge.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'include') diff --git a/include/drm/bridge/aux-bridge.h b/include/drm/bridge/aux-bridge.h index c4c423e97f06..4453906105ca 100644 --- a/include/drm/bridge/aux-bridge.h +++ b/include/drm/bridge/aux-bridge.h @@ -9,6 +9,8 @@ #include +struct auxiliary_device; + #if IS_ENABLED(CONFIG_DRM_AUX_BRIDGE) int drm_aux_bridge_register(struct device *parent); #else @@ -19,10 +21,23 @@ static inline int drm_aux_bridge_register(struct device *parent) #endif #if IS_ENABLED(CONFIG_DRM_AUX_HPD_BRIDGE) +struct auxiliary_device *devm_drm_dp_hpd_bridge_alloc(struct device *parent, struct device_node *np); +int devm_drm_dp_hpd_bridge_add(struct device *dev, struct auxiliary_device *adev); struct device *drm_dp_hpd_bridge_register(struct device *parent, struct device_node *np); void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status status); #else +static inline struct auxiliary_device *devm_drm_dp_hpd_bridge_alloc(struct device *parent, + struct device_node *np) +{ + return NULL; +} + +static inline int devm_drm_dp_hpd_bridge_add(struct auxiliary_device *adev) +{ + return 0; +} + static inline struct device *drm_dp_hpd_bridge_register(struct device *parent, struct device_node *np) { -- cgit