Re: [PATCH 2/3] arm64: dts: qcom: monaco-evk: Add LVDS display overlay

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [High] The device tree overlay specifies an unsupported compatible string `lontium,lt9211c` for the LVDS bridge without a valid fallback, preventing the bridge from probing.
- [Low] The `panel-lvds` node defines a dual-port LVDS panel using the `ports` construct, which violates the strict `panel-lvds` generic schema requirements.
--

--- Patch [2]: [PATCH 2/3] arm64: dts: qcom: monaco-evk: Add LVDS display overlay ---
commit c66e770010c2090d7d3ca762b7283b36aac9f68f
Author: Vishnu Saini <vishnu.saini@oss.qualcomm.com>

arm64: dts: qcom: monaco-evk: Add LVDS display overlay

This commit adds a device tree overlay for the Monaco EVK IFP mezzanine to
support an LVDS display using the Lontium LT9211C bridge. It includes the
bridge node, panel timings, and necessary power routing.

> diff --git a/arch/arm64/boot/dts/qcom/monaco-evk-lvds-boe,dv215fhm-r01.dtso b/arch/arm64/boot/dts/qcom/monaco-evk-lvds-boe,dv215fhm-r01.dtso
> new file mode 100644
> index 0000000000000..d62f6baeca858
> --- /dev/null
> +++ b/arch/arm64/boot/dts/qcom/monaco-evk-lvds-boe,dv215fhm-r01.dtso
> @@ -0,0 +1,131 @@
> +// SPDX-License-Identifier: BSD-3-Clause
> +/*
> + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
> + */
> +
> +/dts-v1/;
> +/plugin/;
> +
> +#include <dt-bindings/gpio/gpio.h>
> +
> +&{/} {
> +	model = "Qualcomm Technologies, Inc. Monaco-EVK Mezzanine Lvds";
> +
> +	panel_lvds: panel-lvds {
> +		compatible = "boe,dv215fhm-r01", "panel-lvds";
> +		data-mapping = "vesa-24";
> +		width-mm = <476>;
> +		height-mm = <268>;
> +		power-supply = <&lcd_disp_bias>;
> +
> +		status = "okay";
> +
> +		panel-timing {

[ ... ]

> +		};
> +
> +		ports {
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +
> +			port@0 {
> +				reg = <0>;

[Severity: Low]
Will this ports construct fail device tree schema validation?

The panel-lvds.yaml schema generally mandates unevaluatedProperties: false
and only accepts a single port node, rejecting the ports container used for
dual-link mapping. Does this pass make dtbs_check?

> +				dual-lvds-odd-pixels;
> +				panel_in_lvds_odd: endpoint {
> +					remote-endpoint = <&lt9211c_out_odd>;
> +				};
> +			};

[ ... ]

> +&i2c8 {
> +	#address-cells = <1>;
> +	#size-cells = <0>;
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&qup_i2c8_data_clk>;
> +
> +	status = "okay";
> +
> +	lt9211c_codec: lvds-bridge@2d {
> +		compatible = "lontium,lt9211c";
> +		reg = <0x2d>;

[Severity: High]
Will this bridge actually probe with this compatible string?

The string "lontium,lt9211c" appears to be unhandled by the kernel, lacking
a fallback (such as "lontium,lt9211"). Could this prevent the device from
binding to the driver and leave the display pipeline non-functional?

> +		reset-gpios = <&tlmm 66 GPIO_ACTIVE_HIGH>;
> +		vccio-supply = <&vreg_l5a>;

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260719-lvds-support-v1-0-1f1aca3213ba@oss.qualcomm.com?part=2