Re: [PATCH v5 3/4] arm64: dts: rockchip: Add devicetree for the FriendlyElec NanoPi R28S

[Jonas Karlman <jonas@kwiboo.se>]

Hi,

On 9/14/2026 10:24 AM, 安容 via B4 Relay wrote:
> From: 安容 <HystericalDragons@proton.me>
> 
> The NanoPi R28S is a dual gigabit Ethernet router board based on the
> Rockchip RK3528 SoC, designed and developed by FriendlyElec. It shares
> most of its design with the NanoPi Zero2, so it builds on the common
> rk3528-nanopi.dtsi.
> 
> Specification:
> - Rockchip RK3528
> - 1GB RAM
> - eMMC socket (optional)
> - MicroSD slot
> - 1x 1000Base-T (GMAC1, Realtek RTL8211F)
> - 1x 1000Base-T (PCIe, Realtek RTL8111H)
> - AICSemi AIC8800D80 SDIO WiFi
> - 3x LEDs (SYS, LAN, WAN)
> - 1x USB 2.0 Type-C, peripheral only, shared with the 5V power input
> - User and MaskROM buttons
> - Haoyu HYM8563 RTC
> - 1x USB Type-C debug UART (onboard WCH CH340E)
> 
> Assisted-by: LLM
> Signed-off-by: 安容 <HystericalDragons@proton.me>
> ---
>  arch/arm64/boot/dts/rockchip/Makefile              |   1 +
>  .../arm64/boot/dts/rockchip/rk3528-nanopi-r28s.dts | 127 +++++++++++++++++++++
>  2 files changed, 128 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/rockchip/Makefile b/arch/arm64/boot/dts/rockchip/Makefile
> index b677914cd3..51a9889088 100644
> --- a/arch/arm64/boot/dts/rockchip/Makefile
> +++ b/arch/arm64/boot/dts/rockchip/Makefile
> @@ -94,6 +94,7 @@ dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3399-vicharak-vaaman.dtb
>  dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3399pro-rock-pi-n10.dtb
>  dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3528-armsom-sige1.dtb
>  dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3528-hinlink-h28k.dtb
> +dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3528-nanopi-r28s.dtb
>  dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3528-nanopi-zero2.dtb
>  dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3528-radxa-e20c.dtb
>  dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3528-rock-2a.dtb
> diff --git a/arch/arm64/boot/dts/rockchip/rk3528-nanopi-r28s.dts b/arch/arm64/boot/dts/rockchip/rk3528-nanopi-r28s.dts
> new file mode 100644
> index 0000000000..0b7bbc0122
> --- /dev/null
> +++ b/arch/arm64/boot/dts/rockchip/rk3528-nanopi-r28s.dts
> @@ -0,0 +1,127 @@
> +// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
> +/*
> + * Copyright (c) 2022 Rockchip Electronics Co., Ltd.
> + * Copyright (c) 2026 FriendlyElec Computer Tech. Co., Ltd.
> + * Copyright (c) 2026 安容 <HystericalDragons@proton.me>
> + */
> +
> +/dts-v1/;
> +
> +#include <dt-bindings/leds/common.h>
> +#include "rk3528-nanopi.dtsi"
> +
> +/ {
> +	model = "FriendlyElec NanoPi R28S";
> +	compatible = "friendlyarm,nanopi-r28s", "rockchip,rk3528";
> +
> +	aliases {
> +		mmc2 = &sdio0;

This looks to be missing an serial2 alias:

	serial2 = &uart2;

> +	};
> +
> +	gpio-keys {
> +		compatible = "gpio-keys";
> +		pinctrl-names = "default";
> +		pinctrl-0 = <&usr_btn>;

This is named gpio4_b2_usr_btn in the schematics.

> +
> +		button-user {
> +			debounce-interval = <50>;
> +			gpios = <&gpio4 RK_PB2 GPIO_ACTIVE_LOW>;
> +			label = "USER";
> +			linux,code = <BTN_1>;
> +			wakeup-source;
> +		};
> +	};
> +
> +	sdio_pwrseq: sdio-pwrseq {
> +		compatible = "mmc-pwrseq-simple";
> +		pinctrl-names = "default";
> +		pinctrl-0 = <&pwr_wf>;
> +		post-power-on-delay-ms = <100>;
> +		reset-gpios = <&gpio1 RK_PC2 GPIO_ACTIVE_LOW>;
> +	};
> +};
> +
> +&combphy {
> +	status = "okay";
> +};
> +
> +&leds {
> +	pinctrl-0 = <&led1>, <&led2>, <&led_sys>;
> +
> +	led-1 {
> +		color = <LED_COLOR_ID_GREEN>;
> +		default-state = "off";
> +		function = LED_FUNCTION_WAN;
> +		gpios = <&gpio4 RK_PB1 GPIO_ACTIVE_HIGH>;
> +		linux,default-trigger = "netdev";
> +	};
> +
> +	led-2 {
> +		color = <LED_COLOR_ID_GREEN>;
> +		default-state = "off";
> +		function = LED_FUNCTION_LAN;
> +		gpios = <&gpio4 RK_PB3 GPIO_ACTIVE_HIGH>;
> +		linux,default-trigger = "netdev";
> +	};
> +};
> +
> +&pcie {
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&pcie_eth_perstb>;
> +	reset-gpios = <&gpio4 RK_PC0 GPIO_ACTIVE_HIGH>;
> +	vpcie3v3-supply = <&vcc_3v3>;
> +
> +	status = "okay";
> +};
> +
> +&pinctrl {

This is missing nodes for bluetooth:

	bluetooth {
		bt_wake_host: bt-wake-host {
			rockchip,pins = <1 RK_PB5 RK_FUNC_GPIO &pcfg_pull_down>;
		};

		host_wake_bt: host-wake-bt {
			rockchip,pins = <1 RK_PB4 RK_FUNC_GPIO &pcfg_pull_none>;
		};
	};

> +	gpio-keys {
> +		usr_btn: usr-btn {

Label should be named gpio4_b2_usr_btn to match schematics.

> +			rockchip,pins = <4 RK_PB2 RK_FUNC_GPIO &pcfg_pull_up>;
> +		};
> +	};
> +
> +	leds {
> +		led2: led2 {
> +			rockchip,pins = <4 RK_PB3 RK_FUNC_GPIO &pcfg_pull_none>;
> +		};
> +	};
> +
> +	pcie {
> +		pcie_eth_perstb: pcie-eth-perstb {
> +			rockchip,pins = <4 RK_PC0 RK_FUNC_GPIO &pcfg_pull_none>;
> +		};
> +	};
> +
> +	wifi {

Suggest you also add host_wake_wl:

		host_wake_wl: host-wake-wl {
			rockchip,pins = <1 RK_PA6 RK_FUNC_GPIO &pcfg_pull_none>;
		};

> +		pwr_wf: pwr-wf {
> +			rockchip,pins = <1 RK_PC2 RK_FUNC_GPIO &pcfg_pull_none>;
> +		};

and wl_wake_host:

		wl_wake_host: wl-wake-host {
			rockchip,pins = <1 RK_PA7 RK_FUNC_GPIO &pcfg_pull_down>;
		};

> +	};
> +};
> +
> +&sdio0 {
> +	bus-width = <4>;
> +	cap-sd-highspeed;
> +	cap-sdio-irq;
> +	keep-power-in-suspend;
> +	mmc-pwrseq = <&sdio_pwrseq>;

We can likely be explicit and declare:

	no-mmc;
	no-sd;

> +	non-removable;
> +	sd-uhs-sdr104;

This is missing the vmmc-supply used.

	vmmc-supply = <&vcc_3v3>;

> +	vqmmc-supply = <&vcc_1v8>;
> +
> +	status = "okay";
> +};
> +
> +&uart2 {

We can likely declare dma-names here:

	dma-names = "tx", "rx";

> +	pinctrl-names = "default";
> +	pinctrl-0 = <&uart2m1_xfer>, <&uart2m1_ctsn>, <&uart2m1_rtsn>;
> +	uart-has-rtscts;
> +
> +	status = "okay";
> +};
> +
> +&usb_host0_xhci {
> +	/* Type-C port, shared with the 5V power input */
> +	dr_mode = "peripheral";

Why do you disable dual role here? Is it not possible to have it work in
host mode? E.g. using a USB hub with power pass-thru?

> +};
> 

Other than above this closely matches what I played around with in
U-Boot [1] a few weeks ago. Main objective was to add NEO3 Plus support,
and only added the R28S DT based on schematics. My R28S should arrive
any day now :-)

[1] https://git.u-boot-project.org/u-boot/contributors/kwiboo/u-boot/-/commit/40382468ba7ce9aa2e7dcde0e59003fd0d220b43

Regards,
Jonas