Re: [PATCH 3/3] arm64: dts: rockchip: Add support for FriendlyElec NanoPC-T6 Plus

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Missing 3.3V regulator for the 4G LTE M.2 B-key connector and incorrect assignment of a 5V regulator.
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commit 5412bbe217132fabf745d86e1c28d6b071b41043
Author: Diederik de Haas <diederik@cknow-tech.com>

arm64: dts: rockchip: Add support for FriendlyElec NanoPC-T6 Plus

This commit introduces basic support for the FriendlyElec NanoPC-T6 Plus.
It highlights the hardware differences from the NanoPC-T6 LTS, such as the
addition of an M.2 B-key connector for a 4G LTE module.

Link: https://wiki.friendlyelec.com/wiki/index.php/NanoPC-T6_Plus
Link: https://wiki.friendlyelec.com/wiki/images/a/ad/NanoPC-T6_Plus_2511_SCH.pdf
Link: http://everest-semi.com/pdf/ES8389%20PB.pdf

> diff --git a/arch/arm64/boot/dts/rockchip/rk3588-nanopc-t6-plus.dts b/arch/arm64/boot/dts/rockchip/rk3588-nanopc-t6-plus.dts
> new file mode 100644
> index 0000000000000..f23ac4bd9f167
> --- /dev/null
> +++ b/arch/arm64/boot/dts/rockchip/rk3588-nanopc-t6-plus.dts
> @@ -0,0 +1,91 @@
> +// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
> +/*
> + * Copyright (c) 2021 Rockchip Electronics Co., Ltd.
> + * Copyright (c) 2023 Thomas McKahan
> + * Copyright (c) 2024 Linaro Ltd.
> + */
> +
> +/dts-v1/;
> +
> +#include "rk3588-nanopc-t6.dtsi"
> +
> +/ {
> +	model = "FriendlyElec NanoPC-T6 Plus";
> +	compatible = "friendlyarm,nanopc-t6-plus", "rockchip,rk3588";
> +
> +	codec_es_3v3: regulator-codec-es-3v3 {
> +		compatible = "regulator-fixed";
> +		regulator-min-microvolt = <3300000>;
> +		regulator-max-microvolt = <3300000>;
> +		regulator-name = "codec_es_3v3";
> +		vin-supply = <&vcc4v0_sys>;
> +	};
> +
> +	usb2_port_5v: regulator-usb2-port-5v {
> +		compatible = "regulator-fixed";
> +		enable-active-high;
> +		gpio = <&gpio1 RK_PA4 GPIO_ACTIVE_HIGH>;
> +		pinctrl-0 = <&usb20_host_pwren_h_pin>;
> +		pinctrl-names = "default";
> +		regulator-min-microvolt = <5000000>;
> +		regulator-max-microvolt = <5000000>;

[Severity: Medium]
Is it correct to define this regulator with a 5V constraint?

This uses the exact GPIO (gpio1 RK_PA4) previously used for the removed USB hub
on the LTS board and retains the 5V constraint, whereas the new M.2 B-key slot
would typically need a 3.3V regulator instead.

> +		regulator-name = "usb2_port_5v";
> +		vin-supply = <&vcc5v0_sys>;
> +	};
> +};

[ ... ]

> +&u2phy2_host {
> +	phy-supply = <&usb2_port_5v>;

[Severity: Medium]
Could this assignment provide the wrong voltage to the 4G LTE module?

Assigning the 5V regulator to the USB PHY port that typically connects to the
4G LTE module's M.2 B-key slot incorrectly requests a 5V supply instead of the
required 3.3V. This could result in the module failing to receive power or
operating with incorrect regulator parameters.

> +};

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260907122406.1862398-1-diederik@cknow-tech.com?part=3