Will be useful for bridge drivers that want to do bus format negotiation with their neighbours.
Signed-off-by: Boris Brezillon boris.brezillon@collabora.com --- Changes in v3: * Inline drm_bridge_chain_get_prev_bridge() * Fix the doc
Changes in v2: * Fix the kerneldoc * Drop the !bridge || !bridge->encoder check --- include/drm/drm_bridge.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h index 2beb1ef9a733..3fb518494640 100644 --- a/include/drm/drm_bridge.h +++ b/include/drm/drm_bridge.h @@ -526,6 +526,22 @@ drm_bridge_chain_get_next_bridge(struct drm_bridge *bridge) return list_next_entry(bridge, chain_node); }
+/** + * drm_bridge_chain_get_prev_bridge() - Get the previous bridge in the chain + * @bridge: bridge object + * + * RETURNS: + * the previous bridge in the chain, or NULL if @bridge is the first. + */ +static inline struct drm_bridge * +drm_bridge_chain_get_prev_bridge(struct drm_bridge *bridge) +{ + if (list_is_first(&bridge->chain_node, &bridge->encoder->bridge_chain)) + return NULL; + + return list_prev_entry(bridge, chain_node); +} + /** * drm_bridge_chain_get_first_bridge() - Get the first bridge in the chain * @encoder: encoder object