ARM: dts: aspeed: Add ADC for AST2600 and enable for Rainier and Everest

Add the ADC nodes to the AST2600 devicetree. Enable ADC1 for Rainier and
Everest systems and add an iio-hwmon node for the 7th channel to report
the battery voltage.

Tested on Rainier:
~# cat /sys/class/hwmon/hwmon11/in1_input
1347
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20210916210045.31769-1-eajames@linux.ibm.comSigned-off-by: Joel Stanley <joel@jms.id.au>

arch/arm/boot/dts/aspeed-bmc-ibm-everest.dts

@@ -243,6 +243,21 @@ led-pcieslot-power {
 			gpios = <&gpio0 ASPEED_GPIO(P, 4) GPIO_ACTIVE_LOW>;
 		};
 	};
+
+	iio-hwmon {
+		compatible = "iio-hwmon";
+		io-channels = <&adc1 7>;
+	};
+};
+
+&adc1 {
+	status = "okay";
+	aspeed,int-vref-microvolt = <2500000>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_adc8_default &pinctrl_adc9_default
+				 &pinctrl_adc10_default &pinctrl_adc11_default
+				 &pinctrl_adc12_default &pinctrl_adc13_default
+				 &pinctrl_adc14_default &pinctrl_adc15_default>;
 };
 
 &gpio0 {

arch/arm/boot/dts/aspeed-bmc-ibm-rainier.dts

@@ -246,6 +246,21 @@ fan5-presence {
 			linux,code = <11>;
 		};
 	};
+
+	iio-hwmon {
+		compatible = "iio-hwmon";
+		io-channels = <&adc1 7>;
+	};
+};
+
+&adc1 {
+	status = "okay";
+	aspeed,int-vref-microvolt = <2500000>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_adc8_default &pinctrl_adc9_default
+		&pinctrl_adc10_default &pinctrl_adc11_default
+		&pinctrl_adc12_default &pinctrl_adc13_default
+		&pinctrl_adc14_default &pinctrl_adc15_default>;
 };
 
 &ehci1 {

arch/arm/boot/dts/aspeed-g6.dtsi

@@ -364,6 +364,26 @@ xdma: xdma@1e6e7000 {
 				status = "disabled";
 			};
 
+			adc0: adc@1e6e9000 {
+				compatible = "aspeed,ast2600-adc0";
+				reg = <0x1e6e9000 0x100>;
+				clocks = <&syscon ASPEED_CLK_APB2>;
+				resets = <&syscon ASPEED_RESET_ADC>;
+				interrupts = <GIC_SPI 46 IRQ_TYPE_LEVEL_HIGH>;
+				#io-channel-cells = <1>;
+				status = "disabled";
+			};
+
+			adc1: adc@1e6e9100 {
+				compatible = "aspeed,ast2600-adc1";
+				reg = <0x1e6e9100 0x100>;
+				clocks = <&syscon ASPEED_CLK_APB2>;
+				resets = <&syscon ASPEED_RESET_ADC>;
+				interrupts = <GIC_SPI 46 IRQ_TYPE_LEVEL_HIGH>;
+				#io-channel-cells = <1>;
+				status = "disabled";
+			};
+
 			gpio0: gpio@1e780000 {
 				#gpio-cells = <2>;
 				gpio-controller;