[PATCH 0/6] drm: handle IRQ_HPD events correctly

Dmitry Baryshkov
2026-04-15T23:22:39Z

Both DisplayPort and HDMI standards define a way for the Sink / display
to notify the Source / host about some kinds of events. In case of HDMI
it's as simple as singnalling changes to the EDID. In case of
DisplayPort it's more complicated and requires actual checking of the
DPCD registers.

Currently USB-C drivers don't have a way to deliver the IRQ_HPD
notifications, leading to missing MST notifications. Provide necessary
plumbing to let IRQ_HPD events be passed to the DisplayPort drivers.

Note: the Yoga C630 UCSI driver and Acer Aspire1 EC driver are not yet
enabled to send the IRQ_HPD events. Both of them would need some more
reverse engineering to find out how the event is being reported by the
EC.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
---
Dmitry Baryshkov (6):
drm/connector: report IRQ_HPD events to drm_connector_oob_hotplug_event()
drm/bridge: pass down IRQ_HPD to the drivers
drm/bridge: aux-hpd: let drivers pass IRQ_HPD events
drm/msm: dp: handle the IRQ_HPD events reported by USB-C
soc: qcom: pmic-glink-altmode: pass down HPD_IRQ events
usb: typec: ucsi: huawei-gaokun: pass down HPD_IRQ events

drivers/gpu/drm/bridge/aux-hpd-bridge.c | 9 +++++---
drivers/gpu/drm/bridge/chrontel-ch7033.c | 2 +-
drivers/gpu/drm/bridge/lontium-lt8912b.c | 2 +-
drivers/gpu/drm/bridge/lontium-lt9611uxc.c | 3 ++-
drivers/gpu/drm/bridge/ti-tfp410.c | 2 +-
drivers/gpu/drm/display/drm_bridge_connector.c | 21 ++++++++++--------
drivers/gpu/drm/drm_bridge.c | 18 ++++++++++------
drivers/gpu/drm/drm_connector.c | 6 ++++--
drivers/gpu/drm/i915/display/intel_dp.c | 3 ++-
drivers/gpu/drm/meson/meson_encoder_hdmi.c | 3 ++-
drivers/gpu/drm/msm/dp/dp_display.c | 6 +++++-
drivers/gpu/drm/msm/dp/dp_drm.h | 3 ++-
drivers/gpu/drm/omapdrm/dss/hdmi4.c | 3 ++-
drivers/soc/qcom/pmic_glink_altmode.c | 4 +++-
drivers/usb/typec/altmodes/displayport.c | 12 +++++++----
drivers/usb/typec/ucsi/ucsi_huawei_gaokun.c | 9 ++++----
include/drm/bridge/aux-bridge.h | 13 +++++++++--
include/drm/drm_bridge.h | 30 +++++++++++++++++++++-----
include/drm/drm_connector.h | 6 ++++--
19 files changed, 107 insertions(+), 48 deletions(-)
---
base-commit: 66672af7a095d89f082c5327f3b15bc2f93d558e
change-id: 20260414-hpd-irq-events-e72bc076a5f1

Best regards,
--
With best wishes
Dmitry