Commit 5164553d authored by Luca Ceresoli's avatar Luca Ceresoli
Browse files

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: default avatarMaxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20250509-drm-bridge-convert-to-alloc-api-v3-20-b8bc1f16d7aa@bootlin.com


Signed-off-by: default avatarLuca Ceresoli <luca.ceresoli@bootlin.com>
parent afb903c0

drivers/gpu/drm/drm_bridge.c

+17 −0
Original line number Diff line number Diff line
@@ -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)

include/drm/drm_bridge.h

+4 −0
Original line number Diff line number Diff line
@@ -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);