arm64: dts: qcom: pm8994: Add VADC node

Add VADC note and some of its channels to allow
for voltage/temperature reading.
Signed-off-by: Konrad Dybcio <konradybcio@gmail.com>
Link: https://lore.kernel.org/r/20201005150313.149754-2-konradybcio@gmail.comSigned-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

arch/arm64/boot/dts/qcom/pm8994.dtsi

 // SPDX-License-Identifier: GPL-2.0
+#include <dt-bindings/iio/qcom,spmi-vadc.h>
+#include <dt-bindings/input/linux-event-codes.h>
 #include <dt-bindings/interrupt-controller/irq.h>
 #include <dt-bindings/spmi/spmi.h>
-#include <dt-bindings/input/linux-event-codes.h>
 
 &spmi_bus {
 
@@ -35,6 +36,39 @@ pwrkey {
 
 		};
 
+		pm8994_vadc: adc@3100 {
+			compatible = "qcom,spmi-vadc";
+			reg = <0x3100>;
+			interrupts = <0x0 0x31 0x0 IRQ_TYPE_EDGE_RISING>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+			#io-channel-cells = <1>;
+
+			adc-chan@7 {
+				reg = <VADC_VSYS>;
+				qcom,pre-scaling = <1 3>;
+				label = "vph_pwr";
+			};
+			adc-chan@8 {
+				reg = <VADC_DIE_TEMP>;
+				label = "die_temp";
+			};
+			adc-chan@9 {
+				reg = <VADC_REF_625MV>;
+				label = "ref_625mv";
+			};
+			adc-chan@a {
+				reg = <VADC_REF_1250MV>;
+				label = "ref_1250mv";
+			};
+			adc-chan@e {
+				reg = <VADC_GND_REF>;
+			};
+			adc-chan@f {
+				reg = <VADC_VDD_VADC>;
+			};
+		};
+
 		pm8994_gpios: gpios@c000 {
 			compatible = "qcom,pm8994-gpio";
 			reg = <0xc000>;