HDMI uses the DDC I2C bus for communicating various bits of link status out of band with the actual HDMI video signal. This information can be useful for debugging issues like questionable cables sabotaged by feline teeth, Enthusiast Grade cables made of cow fencing wire, and other such problems that ruin one's media viewing plans.
Consequently, this series exposes various bits of pertinent information from the SCDC protocol in an HDMI connector's debugfs. To continually poll the link status, userspace can poll the debugfs file. --- Changes in v2: - Add HDMI 2.1 SCDC status reporting - Link to v1: https://patch.msgid.link/[email protected] To: Maarten Lankhorst <[email protected]> To: Maxime Ripard <[email protected]> To: Thomas Zimmermann <[email protected]> To: David Airlie <[email protected]> To: Simona Vetter <[email protected]> To: Andrzej Hajda <[email protected]> To: Neil Armstrong <[email protected]> To: Robert Foss <[email protected]> To: Laurent Pinchart <[email protected]> To: Jonas Karlman <[email protected]> To: Jernej Skrabec <[email protected]> To: Luca Ceresoli <[email protected]> To: Daniel Stone <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Signed-off-by: Nicolas Frattaroli <[email protected]> --- Nicolas Frattaroli (3): drm/scdc-helper: Add scdc_status debugfs entry drm/display: bridge_connector: init scdc debugfs for HDMI drm/scdc-helper: Implement parsing and printing HDMI 2.1 fields drivers/gpu/drm/display/drm_bridge_connector.c | 4 + drivers/gpu/drm/display/drm_scdc_helper.c | 341 +++++++++++++++++++++++++ include/drm/display/drm_scdc.h | 9 + include/drm/display/drm_scdc_helper.h | 113 ++++++++ 4 files changed, 467 insertions(+) --- base-commit: 7d39df83e93eba14a23b1fb6ffff076eb191f27b change-id: 20260413-scdc-link-health-89326013d96c Best regards, -- Nicolas Frattaroli <[email protected]>
