Commit 009d855a26fd ("arm64: dts: mt8183: add dpi node to mt8183") adds
a device-tree node for the DPI display interface that feeds the external
display pipeline, to enable HDMI support on the Pumpkin board.

However, the external display is not fully described on Chrome devices,
blocked by further work on DP / USB-C muxing graph bindings. This
incomplete description currently breaks internal display at least on the
Cozmo board. The same issue was found and fixed on MT8186 devices with
commit 3079fb09ddac ("arm64: dts: mediatek: mt8186-corsola: Disable DPI
display interface"), but the MT8183 change wasn't merged until then.

Disable the external display interface for the Kukui device family until
the necessary work is done, like in the MT8186 Corsola case.

Fixes: 009d855a26fd ("arm64: dts: mt8183: add dpi node to mt8183")
Link: https://lore.kernel.org/linux-mediatek/20240821042836.2631815-1-wenst@chromium.org/
Signed-off-by: Alper Nebi Yasak <alpernebiyasak@gmail.com>
---

 arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi b/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi
index 22924f61ec9e..07ae3c8e897b 100644
--- a/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi
+++ b/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi
@@ -290,6 +290,11 @@ dsi_out: endpoint {
 	};
 };
 
+&dpi0 {
+	/* TODO Re-enable after DP to Type-C port muxing can be described */
+	status = "disabled";
+};
+
 &gic {
 	mediatek,broken-save-restore-fw;
 };

base-commit: 7083504315d64199a329de322fce989e1e10f4f7
-- 
2.45.2

On Tue, Sep 17, 2024 at 12:30 AM Alper Nebi Yasak
<alpernebiyasak@gmail.com> wrote:
>
> Commit 009d855a26fd ("arm64: dts: mt8183: add dpi node to mt8183") adds
> a device-tree node for the DPI display interface that feeds the external
> display pipeline, to enable HDMI support on the Pumpkin board.
>
> However, the external display is not fully described on Chrome devices,
> blocked by further work on DP / USB-C muxing graph bindings. This
> incomplete description currently breaks internal display at least on the
> Cozmo board. The same issue was found and fixed on MT8186 devices with
> commit 3079fb09ddac ("arm64: dts: mediatek: mt8186-corsola: Disable DPI
> display interface"), but the MT8183 change wasn't merged until then.
>
> Disable the external display interface for the Kukui device family until
> the necessary work is done, like in the MT8186 Corsola case.
>
> Fixes: 009d855a26fd ("arm64: dts: mt8183: add dpi node to mt8183")
> Link: https://lore.kernel.org/linux-mediatek/20240821042836.2631815-1-wenst@chromium.org/
> Signed-off-by: Alper Nebi Yasak <alpernebiyasak@gmail.com>
> ---
>
>  arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi b/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi
> index 22924f61ec9e..07ae3c8e897b 100644
> --- a/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi
> +++ b/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi
> @@ -290,6 +290,11 @@ dsi_out: endpoint {
>         };
>  };
>
> +&dpi0 {
> +       /* TODO Re-enable after DP to Type-C port muxing can be described */
> +       status = "disabled";
> +};
> +
>  &gic {
>         mediatek,broken-save-restore-fw;
>  };
>
> base-commit: 7083504315d64199a329de322fce989e1e10f4f7
> --
> 2.45.2
>
Reviewed-by: Pin-yen Lin <treapking@chromium.org>

Thanks for fixing this!