[PATCH v4 0/8] drm: handle IRQ_HPD events correctly

[Dmitry Baryshkov]

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 at oss.qualcomm.com>
---
Changes in v4:
- Renamed drm_connector_oob_hotplug_event() to
  drm_connector_dp_oob_status() (Maxime)
- Reworked commit messages, explaining what it is about (Bjorn)
- Rearranged commits, making them a bit more logical.
- Link to v3: https://patch.msgid.link/20260421-hpd-irq-events-v3-0-44d2bf40dfc2@oss.qualcomm.com

Changes in v3:
- Fixed build error if aux bridges are disabled (Intel GFX CI)
- Link to v2: https://patch.msgid.link/20260420-hpd-irq-events-v2-0-402ffe27e9e9@oss.qualcomm.com

Changes in v2:
- Change irq_hpd arg to be an enum, possibly desribing other uses (Toni)
- Account for that, chaning the API accordingly (with_irq -> extra,
  etc.)
- Wire up AUX bridge notifications
- Link to v1: https://patch.msgid.link/20260416-hpd-irq-events-v1-0-1ab1f1cfb2b2@oss.qualcomm.com

To: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
To: Maxime Ripard <mripard at kernel.org>
To: Thomas Zimmermann <tzimmermann at suse.de>
To: David Airlie <airlied at gmail.com>
To: Simona Vetter <simona at ffwll.ch>
To: Heikki Krogerus <heikki.krogerus at linux.intel.com>
To: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
To: Andrzej Hajda <andrzej.hajda at intel.com>
To: Neil Armstrong <neil.armstrong at linaro.org>
To: Robert Foss <rfoss at kernel.org>
To: Laurent Pinchart <Laurent.pinchart at ideasonboard.com>
To: Jonas Karlman <jonas at kwiboo.se>
To: Jernej Skrabec <jernej.skrabec at gmail.com>
To: Luca Ceresoli <luca.ceresoli at bootlin.com>
To: Jani Nikula <jani.nikula at linux.intel.com>
To: Rodrigo Vivi <rodrigo.vivi at intel.com>
To: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
To: Tvrtko Ursulin <tursulin at ursulin.net>
To: Francesco Dolcini <francesco at dolcini.it>
To: Kevin Hilman <khilman at baylibre.com>
To: Jerome Brunet <jbrunet at baylibre.com>
To: Martin Blumenstingl <martin.blumenstingl at googlemail.com>
To: Rob Clark <robin.clark at oss.qualcomm.com>
To: Dmitry Baryshkov <lumag at kernel.org>
To: Abhinav Kumar <abhinav.kumar at linux.dev>
To: Jessica Zhang <jesszhan0024 at gmail.com>
To: Sean Paul <sean at poorly.run>
To: Marijn Suijten <marijn.suijten at somainline.org>
To: Tomi Valkeinen <tomi.valkeinen at ideasonboard.com>
To: Bjorn Andersson <andersson at kernel.org>
To: Konrad Dybcio <konradybcio at kernel.org>
To: Pengyu Luo <mitltlatltl at gmail.com>
Cc: dri-devel at lists.freedesktop.org
Cc: linux-kernel at vger.kernel.org
Cc: linux-usb at vger.kernel.org
Cc: intel-gfx at lists.freedesktop.org
Cc: intel-xe at lists.freedesktop.org
Cc: linux-amlogic at lists.infradead.org
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-arm-msm at vger.kernel.org
Cc: freedreno at lists.freedesktop.org

---
Dmitry Baryshkov (8):
      drm/connector: report out-of-band IRQ_HPD events
      drm/connector: pass down IRQ_HPD to the drivers
      drm/bridge: aux-hpd: let drivers pass IRQ_HPD events
      drm/bridge: pass extra events to the HPD callback
      drm/bridge: pass down IRQ_HPD to the drivers
      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        | 11 +++++----
 drivers/gpu/drm/bridge/chrontel-ch7033.c       |  3 ++-
 drivers/gpu/drm/bridge/lontium-lt8912b.c       |  3 ++-
 drivers/gpu/drm/bridge/lontium-lt9611uxc.c     |  3 ++-
 drivers/gpu/drm/bridge/ti-tfp410.c             |  3 ++-
 drivers/gpu/drm/display/drm_bridge_connector.c | 22 ++++++++++--------
 drivers/gpu/drm/drm_bridge.c                   | 20 ++++++++++-------
 drivers/gpu/drm/drm_connector.c                | 22 ++++++++++--------
 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            | 10 +++++----
 drivers/gpu/drm/msm/dp/dp_drm.h                |  3 ++-
 drivers/gpu/drm/omapdrm/dss/hdmi4.c            |  3 ++-
 drivers/soc/qcom/pmic_glink_altmode.c          |  6 ++++-
 drivers/usb/typec/altmodes/displayport.c       | 23 ++++++++++++-------
 drivers/usb/typec/ucsi/ucsi_huawei_gaokun.c    | 11 +++++----
 include/drm/bridge/aux-bridge.h                | 13 +++++++++--
 include/drm/drm_bridge.h                       | 31 +++++++++++++++++++++-----
 include/drm/drm_connector.h                    | 24 +++++++++++++++++---
 19 files changed, 152 insertions(+), 65 deletions(-)
---
base-commit: 6e845bcb78c95af935094040bd4edc3c2b6dd784
change-id: 20260414-hpd-irq-events-e72bc076a5f1

Best regards,
--  
With best wishes
Dmitry