[PATCH] arm64: dts: rockchip: Add buttons to Kobol Helios64

[PATCH] arm64: dts: rockchip: Add buttons to Kobol Helios64

[Igor Velkov via B4 Relay]

From: Igor Velkov <iav@iav.lv>

The Helios64 front panel has Power and Recovery buttons. Power is
wired to GPIO0_A5 and Recovery to SARADC channel 1. The board also
routes a User1 button signal to GPIO0_A3 on front panel header P3.

Describe Power and User1 as gpio-keys and Recovery as adc-keys.
The SARADC reference is the 1V8_S3 rail from RK808 LDO_REG3, so add
that regulator.

Assisted-by: LLM
Signed-off-by: Igor Velkov <iav@iav.lv>
---
Tested on 7.3-rc5 with evtest: Power reports KEY_POWER, Recovery
reports BTN_1. Power wakes the board from s2idle. User1 has no button
on the enclosure and is untested.
---
 .../boot/dts/rockchip/rk3399-kobol-helios64.dts    | 64 ++++++++++++++++++++++
 1 file changed, 64 insertions(+)

diff --git a/arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts b/arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts
index b2de018a7d36..d146e5075b4f 100644
--- a/arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts
@@ -11,6 +11,7 @@
  */
 
 /dts-v1/;
+#include <dt-bindings/input/input.h>
 #include "rk3399.dtsi"
 
 / {
@@ -23,6 +24,20 @@ aliases {
 		mmc1 = &sdhci;
 	};
 
+	adc-keys {
+		compatible = "adc-keys";
+		io-channels = <&saradc 1>;
+		io-channel-names = "buttons";
+		keyup-threshold-microvolt = <1800000>;
+		poll-interval = <100>;
+
+		button-recovery {
+			label = "Recovery";
+			linux,code = <BTN_1>;
+			press-threshold-microvolt = <100000>;
+		};
+	};
+
 	avdd_0v9_s0: regulator-avdd-0v9-s0 {
 		compatible = "regulator-fixed";
 		regulator-name = "avdd_0v9_s0";
@@ -68,6 +83,27 @@ fan2 {
 		cooling-levels = <0 80 170 255>;
 	};
 
+	gpio-keys {
+		compatible = "gpio-keys";
+		pinctrl-names = "default";
+		pinctrl-0 = <&pwr_btn &user1_btn>;
+
+		button-power {
+			debounce-interval = <100>;
+			gpios = <&gpio0 RK_PA5 GPIO_ACTIVE_LOW>;
+			label = "Power";
+			linux,code = <KEY_POWER>;
+			wakeup-source;
+		};
+
+		button-user1 {
+			debounce-interval = <100>;
+			gpios = <&gpio0 RK_PA3 GPIO_ACTIVE_LOW>;
+			label = "User Button 1";
+			linux,code = <BTN_0>;
+		};
+	};
+
 	leds {
 		compatible = "gpio-leds";
 		pinctrl-names = "default";
@@ -352,6 +388,19 @@ regulator-state-mem {
 				};
 			};
 
+			vcc1v8_s3: LDO_REG3 {
+				regulator-name = "vcc1v8_s3";
+				regulator-always-on;
+				regulator-boot-on;
+				regulator-min-microvolt = <1800000>;
+				regulator-max-microvolt = <1800000>;
+
+				regulator-state-mem {
+					regulator-on-in-suspend;
+					regulator-suspend-microvolt = <1800000>;
+				};
+			};
+
 			vcc_sdio_s0: LDO_REG4 {
 				regulator-name = "vcc_sdio_s0";
 				regulator-always-on;
@@ -434,6 +483,16 @@ &pcie0 {
 };
 
 &pinctrl {
+	buttons {
+		pwr_btn: pwr-btn {
+			rockchip,pins = <0 RK_PA5 RK_FUNC_GPIO &pcfg_pull_up>;
+		};
+
+		user1_btn: user1-btn {
+			rockchip,pins = <0 RK_PA3 RK_FUNC_GPIO &pcfg_pull_none>;
+		};
+	};
+
 	gmac {
 		gphy_reset: gphy-reset {
 			rockchip,pins = <3 RK_PB7 RK_FUNC_GPIO &pcfg_output_low>;
@@ -503,6 +562,11 @@ &pwm1 {
 	status = "okay";
 };
 
+&saradc {
+	vref-supply = <&vcc1v8_s3>;
+	status = "okay";
+};
+
 &sdhci {
 	bus-width = <8>;
 	mmc-hs200-1_8v;

---
base-commit: 23d8f49fcae5d72b77744c7f349c12462c3bb748
change-id: 20260930-helios64-buttons-b93ad4e8ee2e

Best regards,
-- 
Igor Velkov <iav@iav.lv>

Re: [PATCH] arm64: dts: rockchip: Add buttons to Kobol Helios64

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] dts: rockchip: floating User1 button causes interrupt storms
--

commit a839eb665d8bc992ebe29b10a50a8b7e57d5f4f5
Author: Igor Velkov <iav@iav.lv>

arm64: dts: rockchip: Add buttons to Kobol Helios64

The commit adds gpio-keys and adc-keys for the Power, User1, and Recovery
buttons on the Kobol Helios64 board. It also adds the vcc1v8_s3 regulator
reference for the SARADC.

> diff --git a/arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts b/arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts
> index b2de018a7d363..d146e5075b4f8 100644
> --- a/arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts
> +++ b/arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts
[ ... ]
> @@ -68,6 +83,27 @@ fan2 {
>  		cooling-levels = <0 80 170 255>;
>  	};
>  
> +	gpio-keys {
> +		compatible = "gpio-keys";
> +		pinctrl-names = "default";
> +		pinctrl-0 = <&pwr_btn &user1_btn>;
> +
> +		button-power {
> +			debounce-interval = <100>;
> +			gpios = <&gpio0 RK_PA5 GPIO_ACTIVE_LOW>;
> +			label = "Power";
> +			linux,code = <KEY_POWER>;
> +			wakeup-source;
> +		};
> +
> +		button-user1 {
> +			debounce-interval = <100>;
> +			gpios = <&gpio0 RK_PA3 GPIO_ACTIVE_LOW>;
> +			label = "User Button 1";
> +			linux,code = <BTN_0>;
> +		};
> +	};
[ ... ]
> @@ -434,6 +483,16 @@ &pcie0 {
>  };
>  
>  &pinctrl {
> +	buttons {
> +		pwr_btn: pwr-btn {
> +			rockchip,pins = <0 RK_PA5 RK_FUNC_GPIO &pcfg_pull_up>;
> +		};
> +
> +		user1_btn: user1-btn {
> +			rockchip,pins = <0 RK_PA3 RK_FUNC_GPIO &pcfg_pull_none>;
> +		};
> +	};

[Severity: High]
Since the user1 button GPIO (RK_PA3) is registered in gpio-keys as
GPIO_ACTIVE_LOW to generate edge interrupts, does disabling the internal pull-up
with &pcfg_pull_none leave the pin floating?

The commit message notes "User1 has no button on the enclosure and is
untested", meaning the pin is unconnected. Without an internal or external
pull-up, a floating pin will pick up ambient electromagnetic noise and cross the
logic threshold randomly, continuously generating spurious BTN_0 events.

Can this cause interrupt storms that degrade system performance or lead to
unresponsiveness?

Should the pinctrl configuration use &pcfg_pull_up here to prevent the pin from
floating, or should the node remain disabled by default?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260930-helios64-buttons-v1-1-d76249064003@iav.lv?part=1

Re: [PATCH] arm64: dts: rockchip: Add buttons to Kobol Helios64

[Igor Velkov]

On Wed, Sep 30, 2026 at 03:00:34AM +0000, sashiko-bot@kernel.org wrote:
> Since the user1 button GPIO (RK_PA3) is registered in gpio-keys as
> GPIO_ACTIVE_LOW to generate edge interrupts, does disabling the internal pull-up
> with &pcfg_pull_none leave the pin floating?

Not floating: GPIO0_A3 (USR1_SWITCH#) has an external 4.75k pull-up
(R9) to 1V8_S3 on the SoC side of D11, sheet 29 of
https://wiki.kobol.io/helios64/files/schematics/Helios64_Schematics_Rev1.2.pdf
Armbian ships the same pinctrl; with no User1 button attached the
IRQ count stays 0 after 29 minutes of uptime.

Re: [PATCH] arm64: dts: rockchip: Add buttons to Kobol Helios64

[Heiko Stuebner]

On Wed, 30 Sep 2026 05:52:03 +0300, Igor Velkov wrote:
> The Helios64 front panel has Power and Recovery buttons. Power is
> wired to GPIO0_A5 and Recovery to SARADC channel 1. The board also
> routes a User1 button signal to GPIO0_A3 on front panel header P3.
> 
> Describe Power and User1 as gpio-keys and Recovery as adc-keys.
> The SARADC reference is the 1V8_S3 rail from RK808 LDO_REG3, so add
> that regulator.
> 
> [...]

Applied, thanks!

[1/1] arm64: dts: rockchip: Add buttons to Kobol Helios64
      commit: 1e0a0365c73177d55365cdde3a1a179b4897a77b

Best regards,
-- 
Heiko Stuebner <heiko@sntech.de>