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* [PATCH 0/4] drm: bridge: display-connector: Support hardcoding EDID for VGA
@ 2026-07-05 21:35 Laurent Pinchart
  2026-07-05 21:35 ` [PATCH 1/4] dt-bindings: display: vga-connector: Allow hardcoding EDID Laurent Pinchart
                   ` (3 more replies)
  0 siblings, 4 replies; 19+ messages in thread
From: Laurent Pinchart @ 2026-07-05 21:35 UTC (permalink / raw)
  To: dri-devel, devicetree
  Cc: Thuan Nguyen, Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann,
	Rob Herring, Krzysztof Kozlowski, Conor Dooley,
	Geert Uytterhoeven, Magnus Damm, Andrzej Hajda, Neil Armstrong,
	Robert Foss, Jonas Karlman, Jernej Skrabec, Luca Ceresoli,
	linux-renesas-soc

Hello,

In a normal use case, the VGA DDC lines are used to read EDID from the
display. On some systems where the connector is internal to the device
and the VGA display is always present, the DDC lines may not be
connected, making display detection and EDID retrieval impossible.

This patch series adds the ability to hardcode EDID in the device tree
for VGA connectors on such systems. Patch 1/4 extends the vga-connector
DT bindings with an "edid" property. Patch 2/4 is a drive-by fix for a
resource leak in the display-connector driver, and patch 3/4 implements
support for the "edid" property in the driver.

I have tested this on a Renesas Salvator-XS M3N development board. The
board has an external VGA connector, but does not conenct the DDC lines,
exhibiting the problem that this series addresses. Patch 4/4
demonstrates how to set EDID in the device tree, for the VGA monitor I
used in my test environment. It is not meant to be merged as the display
is not internal to the device in this case.

Laurent Pinchart (4):
  dt-bindings: display: vga-connector: Allow hardcoding EDID
  drm/bridge: display-connector: Fix I2C adapter resource leak
  drm/bridge: display-connector: Support hardcoded EDID for VGA
    connectors
  [DNI] arm64: dts: renesas: salvator: Add overlay for Dell P1911 VGA
    display

 .../display/connector/vga-connector.yaml      | 15 +++++++
 arch/arm64/boot/dts/renesas/Makefile          |  2 +
 .../dts/renesas/salvator-vga-dell-p1911.dtso  | 21 ++++++++++
 drivers/gpu/drm/bridge/display-connector.c    | 42 ++++++++++++++++---
 4 files changed, 75 insertions(+), 5 deletions(-)
 create mode 100644 arch/arm64/boot/dts/renesas/salvator-vga-dell-p1911.dtso


base-commit: 44d19b8a7548aa25cbc6ebd5f27e958f7142c36b
-- 
Regards,

Laurent Pinchart


^ permalink raw reply	[flat|nested] 19+ messages in thread

end of thread, other threads:[~2026-07-06 16:02 UTC | newest]

Thread overview: 19+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-07-05 21:35 [PATCH 0/4] drm: bridge: display-connector: Support hardcoding EDID for VGA Laurent Pinchart
2026-07-05 21:35 ` [PATCH 1/4] dt-bindings: display: vga-connector: Allow hardcoding EDID Laurent Pinchart
2026-07-06  8:08   ` Geert Uytterhoeven
2026-07-06 10:03     ` Laurent Pinchart
2026-07-06  8:52   ` Maxime Ripard
2026-07-06  9:45     ` Laurent Pinchart
2026-07-06 15:40       ` Maxime Ripard
2026-07-06 16:02         ` Laurent Pinchart
2026-07-05 21:35 ` [PATCH 2/4] drm/bridge: display-connector: Fix I2C adapter resource leak Laurent Pinchart
2026-07-05 21:48   ` sashiko-bot
2026-07-05 23:38     ` Laurent Pinchart
2026-07-05 21:35 ` [PATCH 3/4] drm/bridge: display-connector: Support hardcoded EDID for VGA connectors Laurent Pinchart
2026-07-05 21:44   ` sashiko-bot
2026-07-05 23:38     ` Laurent Pinchart
2026-07-05 21:35 ` [PATCH 4/4] [DNI] arm64: dts: renesas: salvator: Add overlay for Dell P1911 VGA display Laurent Pinchart
2026-07-05 21:37   ` sashiko-bot
2026-07-05 23:39     ` Laurent Pinchart
2026-07-06  8:16   ` Geert Uytterhoeven
2026-07-06  9:48     ` Laurent Pinchart

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