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+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/afe/voltage-divider.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Voltage divider
+
+maintainers:
+ - Peter Rosin <peda@axentia.se>
+
+description: |
+ When an io-channel measures the midpoint of a voltage divider, the
+ interesting voltage is often the voltage over the full resistance
+ of the divider. This binding describes the voltage divider in such
+ a curcuit.
+
+ Vin ----.
+ |
+ .-----.
+ | R |
+ '-----'
+ |
+ +---- Vout
+ |
+ .-----.
+ | Rout|
+ '-----'
+ |
+ GND
+
+
+properties:
+ compatible:
+ const: voltage-divider
+
+ io-channels:
+ maxItems: 1
+ description: |
+ Channel node of a voltage io-channel.
+
+ output-ohms:
+ description:
+ Resistance Rout over which the output voltage is measured. See full-ohms.
+
+ full-ohms:
+ description:
+ Resistance R + Rout for the full divider. The io-channel is scaled by
+ the Rout / (R + Rout) quotient.
+
+required:
+ - compatible
+ - io-channels
+ - output-ohms
+ - full-ohms
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/irq.h>
+ /*
+ * The system voltage is circa 12V, but divided down with a 22/222
+ * voltage divider (R = 200 Ohms, Rout = 22 Ohms) and fed to an ADC.
+ */
+ spi {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ maxadc: adc@0 {
+ compatible = "maxim,max1027";
+ reg = <0>;
+ #io-channel-cells = <1>;
+ interrupt-parent = <&gpio5>;
+ interrupts = <15 IRQ_TYPE_EDGE_RISING>;
+ spi-max-frequency = <1000000>;
+ };
+ };
+ sysv {
+ compatible = "voltage-divider";
+ io-channels = <&maxadc 1>;
+
+ /* Scale the system voltage by 22/222 to fit the ADC range. */
+ output-ohms = <22>;
+ full-ohms = <222>; /* 200 + 22 */
+ };
+...