Re: [PATCH v3 13/21] drm/bridge: Add the drm_bridge_chain_get_prev_bridge() helper

On 23/10/2019 17:45, Boris Brezillon wrote:

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

Reviewed-by: Neil Armstrong narmstrong@baylibre.com