Re: [PATCH 2/2] arm64: dts: agilex5: add support for debug daughter card

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Low] Abuse of the 'rohm,dh2228fv' compatible string to force the 'spidev' driver to bind.
- [Low] Including a '.dts' file directly instead of using a '.dtsi' include file.
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commit 3916af69e58bdb9bf4d736172238dd0b03e9465b
Author: Adrian Ng Ho Yin <adrian.ho.yin.ng@altera.com>

arm64: dts: agilex5: add support for debug daughter card

This commit adds a new device tree for the Agilex 5 SoCDK when fitted with
the debug daughter card. It disables several peripherals such as gpio0 and
gmac2 while enabling gmac0 and spi0 for debugging purposes.

> diff --git a/arch/arm64/boot/dts/intel/socfpga_agilex5_socdk_debug.dts b/arch/arm64/boot/dts/intel/socfpga_agilex5_socdk_debug.dts
> new file mode 100644
> index 0000000000000..3981a9e876b0a
> --- /dev/null
> +++ b/arch/arm64/boot/dts/intel/socfpga_agilex5_socdk_debug.dts
> @@ -0,0 +1,50 @@
> +// SPDX-License-Identifier:     GPL-2.0
> +/*
> + * Copyright (C) 2026, Altera Corporation
> + */
> +#include "socfpga_agilex5_socdk.dts"

This isn't a bug, but does this include a final board .dts file instead of a
shared .dtsi include?

Standard Device Tree conventions typically involve refactoring shared
configurations into a common .dtsi file, as .dts files are meant to be the
final top-level compilation unit for a board.

[ ... ]

> +&spi0 {
> +	status = "okay";
> +	spidev@0 {
> +		compatible = "rohm,dh2228fv";

Is there actually a Rohm DH2228FV hardware device present on this debug
daughter card?

The commit message indicates this exposes the SPI interface for debugging.
Does this code use the 'rohm,dh2228fv' compatible string solely to force the
Linux spidev driver to bind?

The Device Tree is meant for describing hardware, and using fake hardware
compatible strings to instantiate userspace interfaces bypasses the kernel
warnings against using a bare 'spidev' compatible string.

> +		reg = <0>;
> +		spi-max-frequency = <10000000>;
> +	};
> +};

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/cover.1778237639.git.adrian.ho.yin.ng@altera.com?part=2