arm64: dts: rockchip: enable adc button for Radxa E25

The Radxa E25 board has an ADC button. Enable it.

Signed-off-by: Chukun Pan <amadeus@jmu.edu.cn>
Link: https://patch.msgid.link/20260601101000.2076721-1-amadeus@jmu.edu.cn
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

Author: aiamadeus

arch/arm64/boot/dts/rockchip/rk3568-radxa-e25.dts

@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: (GPL-2.0+ OR MIT)
 
 /dts-v1/;
+#include <dt-bindings/input/input.h>
 #include "rk3568-radxa-cm3i.dtsi"
 
 / {
@@ -11,6 +12,19 @@
 		mmc1 = &sdmmc0;
 	};
 
+	adc-keys {
+		compatible = "adc-keys";
+		io-channels = <&saradc 0>;
+		io-channel-names = "buttons";
+		keyup-threshold-microvolt = <1800000>;
+
+		button-recovery {
+			label = "Recovery";
+			linux,code = <KEY_VENDOR>;
+			press-threshold-microvolt = <0>;
+		};
+	};
+
 	pwm-leds {
 		compatible = "pwm-leds-multicolor";