Currently it is next to impossible to implement CEC handling for the setup using drm_bridges and drm_bridge_connector: bridges don't have a hold of the connector at the proper time to be able to route CEC events.
At the same time it not very easy and obvious to get the CEC physical address handling correctly. Drivers handle it at various places, ending up with the slight differences in behaviour. Follow up the HDMI Connector and HDMI Audio series and implement generic HDMI CEC set of helpers that link into the HDMI Connector and drm_bridge_connector frameworks and provide a way to implement CEC handling for HDMI bridges in an easy yet standard way. Notes: - the patchset was only compile-tested - being an RFC some of the API functions and structures are left undocumented - although the patchset provides drm_bridge / drm_bridge_connector API for working with CEC, there is no actual bridge that uses the API (yet) - I'm pretty unhappy with the drm_bridge integration code, we end up duplicating wrappers for CEC functions instead of reusing the drm_connector wrapping functions. An easy way would be to map drm_bridge to the corresponding drm_connector, but that would either require a state or storing drm_connector inside a drm_bridge. Current code stores cec_adapter instead. Signed-off-by: Dmitry Baryshkov <dmitry.barysh...@linaro.org> --- Changes in v3: - Moved default available_las setting to drm_connector_hdmi_cec_register(), allowing drivers to pass 0 instead of CEC_MAX_LOG_ADDRS. - Reworked drm_bridge interface to store opaque pointer and interpret it as drm_connector in CEC helpers code. - Fixed EINVAL checks in drm_connector_hdmi_cec_register(). - Added the adv7511 patch, demonstrating CEC helpers for the DRM bridges. - Link to v2: https://lore.kernel.org/r/20250110-drm-hdmi-connector-cec-v2-0-9067c8f34...@linaro.org Changes in v2: - Refactored CEC funcs, adding more wrappers to provide more consistent interface (Maxime) - Removed export of drm_connector_cec_unregister() (Maxime) - Restored and rephrased comment in vc4_hdmi (Maxime) - Squashed vc4 patches - Link to v1: https://lore.kernel.org/r/20241225-drm-hdmi-connector-cec-v1-0-b80380c67...@linaro.org --- Dmitry Baryshkov (10): drm/connector: add CEC-related fields drm/display: add CEC helpers code drm/display: hdmi-state-helper: handle CEC physical address drm/vc4: hdmi: switch to generic CEC helpers drm/display: bridge-connector: hook in CEC notifier support drm/bridge: move private data to the end of the struct drm/display: hdmi-cec-helper: add bridge-related functions drm/display: bridge-connector: handle CEC adapters drm/bridge: allow limiting I2S formats drm/bridge: adv7511: switch to the HDMI connector helpers drivers/gpu/drm/bridge/adv7511/Kconfig | 4 + drivers/gpu/drm/bridge/adv7511/adv7511.h | 51 ++-- drivers/gpu/drm/bridge/adv7511/adv7511_audio.c | 77 +----- drivers/gpu/drm/bridge/adv7511/adv7511_cec.c | 56 ++-- drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 342 ++++++++++-------------- drivers/gpu/drm/bridge/adv7511/adv7533.c | 4 - drivers/gpu/drm/bridge/lontium-lt9611.c | 2 +- drivers/gpu/drm/display/Kconfig | 6 + drivers/gpu/drm/display/Makefile | 2 + drivers/gpu/drm/display/drm_bridge_connector.c | 105 +++++++- drivers/gpu/drm/display/drm_hdmi_audio_helper.c | 2 + drivers/gpu/drm/display/drm_hdmi_cec_helper.c | 247 +++++++++++++++++ drivers/gpu/drm/display/drm_hdmi_state_helper.c | 9 +- drivers/gpu/drm/drm_bridge.c | 15 ++ drivers/gpu/drm/drm_connector.c | 13 + drivers/gpu/drm/vc4/Kconfig | 1 + drivers/gpu/drm/vc4/vc4_hdmi.c | 140 ++++------ drivers/gpu/drm/vc4/vc4_hdmi.h | 1 - include/drm/display/drm_hdmi_audio_helper.h | 1 + include/drm/display/drm_hdmi_cec_helper.h | 69 +++++ include/drm/drm_bridge.h | 77 ++++-- include/drm/drm_connector.h | 44 +++ 22 files changed, 834 insertions(+), 434 deletions(-) --- base-commit: 7c3127e4814c304c7d5a2fa796a42e75a9b8606f change-id: 20241223-drm-hdmi-connector-cec-34902ce847b7 Best regards, -- Dmitry Baryshkov <dmitry.barysh...@linaro.org>
