[PATCH 1/3] ARM: dts: aspeed: ventura2: Add LTC2305 ADCs
From: Kyle Hsieh
Date: Thu Nov 05 2026 - 22:03:48 EST
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@xxxxxxxxx>
---
.../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