Re: [PATCH v5 3/5] arm64: dts: imx8mp-skov-revc: convert to overlays

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:
- [High] The TIAN variant overlay incorrectly uses `/ {` instead of `&{/} {`, meaning its root properties will not be applied to the base device tree.
- [High] The `&lcdif2` display controller node was accidentally deleted from the jutouch variant and not added to the common base DT, which will break the display.
- [Medium] In the TIAN overlay, `#address-cells` and `#size-cells` were mistakenly added to `&lcdif2` instead of `&lvds_bridge/ports`, leaving `port@1` without a `reg` property.
--

--- Patch [3]: [PATCH v5 3/5] arm64: dts: imx8mp-skov-revc: convert to overlays ---
commit 3f7282529fd194eae3895a434d1dbbf37a64e617
Author: Steffen Trumtrar <s.trumtrar@pengutronix.de>

arm64: dts: imx8mp-skov-revc: convert to overlays

The i.MX8MP Skov RevC jutouch 10" and Tian 7" variants are similar.
This commit moves the common bindings to imx8mp-skov-revc-touch.dts and
converts both variants to use overlays.

> diff --git a/arch/arm64/boot/dts/freescale/imx8mp-skov-revc-jutouch-jt101tm023.dtso b/arch/arm64/boot/dts/freescale/imx8mp-skov-revc-jutouch-jt101tm023.dtso
> index 3e320d6dea3a2..b50960879e82d 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mp-skov-revc-jutouch-jt101tm023.dts
> +++ b/arch/arm64/boot/dts/freescale/imx8mp-skov-revc-jutouch-jt101tm023.dtso
[ ... ]
> @@ -42,38 +40,20 @@ touchscreen@2a {
>  	};
>  };
>  
> -&lcdif2 {
> -	status = "okay";
> -};
> -

[Severity: High]
Does removing the &lcdif2 node here leave the display controller disabled?
Because this node was not moved to the common imx8mp-skov-revc-touch.dts
base tree, it appears the controller might remain disabled as defined in
the SoC base imx8mp.dtsi, which could break display output for this variant.

>  &lvds_bridge {
> -	assigned-clocks = <&clk IMX8MP_CLK_MEDIA_LDB>,
> -				 <&clk IMX8MP_VIDEO_PLL1>;
> -	assigned-clock-parents = <&clk IMX8MP_VIDEO_PLL1_OUT>;
>  	/* IMX8MP_VIDEO_PLL1 = IMX8MP_CLK_MEDIA_DISP2_PIX * 7 */
>  	assigned-clock-rates = <0>, <506800000>;
> -	status = "okay";
>  
>  	ports {
[ ... ]
> diff --git a/arch/arm64/boot/dts/freescale/imx8mp-skov-revc-tian-g07017.dtso b/arch/arm64/boot/dts/freescale/imx8mp-skov-revc-tian-g07017.dtso
> index 9a562c011f2c2..4f37723dbe8a1 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mp-skov-revc-tian-g07017.dts
> +++ b/arch/arm64/boot/dts/freescale/imx8mp-skov-revc-tian-g07017.dtso
> @@ -1,8 +1,10 @@
>  // SPDX-License-Identifier: (GPL-2.0 OR MIT)
>  
>  /dts-v1/;
> +/plugin/;
>  
> -#include "imx8mp-skov-reva.dtsi"
> +#include <dt-bindings/gpio/gpio.h>
> +#include <dt-bindings/interrupt-controller/irq.h>
>  
>  / {
>  	model = "SKOV IMX8MP CPU revC - TIAN G07017";

[Severity: High]
Does this correctly target the base tree's root? In an overlay, using
/ { ... } defines the root node of the overlay DTB itself rather than
creating a fragment targeting the base tree. Should this use &{/} {
like the jutouch variant so properties like the model and the panel node
are properly merged into the base device tree?

> @@ -21,13 +23,9 @@ in_lvds0: endpoint {
>  	};
>  };
>  
[ ... ]
> @@ -45,16 +43,14 @@ touchscreen@38 {
>  };
>  
>  &lcdif2 {
> +	#address-cells = <1>;
> +	#size-cells = <0>;

[Severity: Medium]
Were these properties intended for the &lvds_bridge/ports node instead?
Adding them to &lcdif2 when there are no unit-addressed children seems
incorrect.

>  	status = "okay";
>  };
>  
>  &lvds_bridge {
> -	assigned-clocks = <&clk IMX8MP_CLK_MEDIA_LDB>,
> -				 <&clk IMX8MP_VIDEO_PLL1>;
> -	assigned-clock-parents = <&clk IMX8MP_VIDEO_PLL1_OUT>;
>  	/* IMX8MP_VIDEO_PLL1 = IMX8MP_CLK_MEDIA_DISP2_PIX * 2 * 7 */
>  	assigned-clock-rates = <0>, <358400000>;
> -	status = "okay";
>  
>  	ports {
>  		port@1 {

[Severity: Medium]
Does port@1 need a reg = <1> property? Without the #address-cells and
#size-cells on the ports node and the reg property here, this can cause
dtc warnings and might fail parsing by the display drivers.

> @@ -64,18 +60,3 @@ ldb_lvds_ch0: endpoint {
>  		};
>  	};
>  };

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260727-v7-0-topic-imx8mp-skov-dts-jutouch-7inch-v5-0-67faa5ee0bf6@pengutronix.de?part=3