From c38830485cb50f5cb17277c9a6b283a530a71b54 Mon Sep 17 00:00:00 2001
From: "wenping.zhang" <wenping.zhang@rock-chips.com>
Date: Mon, 16 Jan 2017 11:44:23 +0800
Subject: [PATCH] arm64: dts: rockchip: add adc key support for rk3399 linux
 project.

we use linux upstream adc key driver to support adc keyboard.

Change-Id: Id93a4ab3d58ff92ce0fc11b35abd4d4b8d3737e0
Signed-off-by: wenping.zhang <wenping.zhang@rock-chips.com>
---
 .../rk3399-sapphire-excavator-linux.dts       | 45 +++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/arch/arm64/boot/dts/rockchip/rk3399-sapphire-excavator-linux.dts b/arch/arm64/boot/dts/rockchip/rk3399-sapphire-excavator-linux.dts
index 64b37120e263..32b45420646e 100644
--- a/arch/arm64/boot/dts/rockchip/rk3399-sapphire-excavator-linux.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3399-sapphire-excavator-linux.dts
@@ -109,6 +109,51 @@
 			debounce-interval = <100>;
 		};
 	};
+
+	vccadc_ref: vccadc-ref {
+		compatible = "regulator-fixed";
+		regulator-name = "vcc1v8_sys";
+		regulator-always-on;
+		regulator-boot-on;
+		regulator-min-microvolt = <1800000>;
+		regulator-max-microvolt = <1800000>;
+	};
+
+	adc-keys {
+		compatible = "adc-keys";
+		io-channels = <&saradc 1>;
+		io-channel-names = "buttons";
+		poll-interval = <100>;
+		keyup-threshold-microvolt = <1800000>;
+
+		button-up {
+			label = "Volume Up";
+			linux,code = <KEY_VOLUMEUP>;
+			press-threshold-microvolt = <100000>;
+		};
+
+		button-down {
+			label = "Volume Down";
+			linux,code = <KEY_VOLUMEDOWN>;
+			press-threshold-microvolt = <300000>;
+		};
+
+		back {
+			label = "Back";
+			linux,code = <KEY_BACK>;
+			press-threshold-microvolt = <985000>;
+		};
+
+		menu {
+			label = "Menu";
+			linux,code = <KEY_MENU>;
+			press-threshold-microvolt = <1314000>;
+		};
+	};
+};
+
+&saradc {
+	vref-supply = <&vccadc_ref>;
 };
 
 &vpu {
-- 
2.34.1