[PATCH 1/3] ARM: dts: aspeed: ventura2: Add LTC2305 ADCs

[Kyle Hsieh <kylehsieh1995@gmail.com>]

Ventura2 has three LTC2305 2-channel 12-bit ADCs: one behind channel 2
of the PCA9548 mux on I2C bus 0, and two on I2C bus 3 at addresses
0x08 and 0x09. The bus 3 ADCs read the valve voltages.

Describe the ADCs and expose the bus 3 channels through iio-hwmon so
the voltages are reported as hwmon sensors.

The ADCs use their internal 4.096V reference, so no vref-supply is
described.

Signed-off-by: Kyle Hsieh <kylehsieh1995@gmail.com>
---
 .../dts/aspeed/aspeed-bmc-facebook-ventura2.dts     | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-ventura2.dts b/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-ventura2.dts
index f3dbdece3076..50e652cc37a1 100644
--- a/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-ventura2.dts
+++ b/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-ventura2.dts
@@ -190,7 +190,8 @@ iio-hwmon {
 		io-channels =
 			<&adc0 0>, <&adc0 1>, <&adc0 2>, <&adc0 3>,
 			<&adc0 4>, <&adc0 5>, <&adc0 6>, <&adc0 7>,
-			<&adc1 2>;
+			<&adc1 2>,
+			<&adc_op_fb1 0>, <&adc_op_fb1 1>, <&adc_op_fb2 0>;
 	};
 
 	leds {
@@ -392,6 +393,12 @@ i2c0mux0ch2: i2c@2 {
 			reg = <2>;
 			#address-cells = <1>;
 			#size-cells = <0>;
+
+			adc@8 {
+				compatible = "lltc,ltc2305";
+				reg = <0x08>;
+				#io-channel-cells = <1>;
+			};
 		};
 
 		i2c0mux0ch3: i2c@3 {
@@ -583,6 +590,18 @@ &i2c3 {
 
 	status = "okay";
 
+	adc_op_fb1: adc@8 {
+		compatible = "lltc,ltc2305";
+		reg = <0x08>;
+		#io-channel-cells = <1>;
+	};
+
+	adc_op_fb2: adc@9 {
+		compatible = "lltc,ltc2305";
+		reg = <0x09>;
+		#io-channel-cells = <1>;
+	};
+
 	dac@c {
 		compatible = "adi,ad5612";
 		reg = <0x0c>;

-- 
2.34.1