An ADC is often used to measure other quantities indirectly. This
binding describe one cases, a current through a shunt resistor
measured by the voltage over it.
Reviewed-by: Rob Herring <r...@kernel.org>
Signed-off-by: Peter Rosin <p...@axentia.se>
---
.../bindings/iio/afe/current-sense-shunt.txt | 41 ++++++++++++++++++++++
MAINTAINERS | 6 ++++
2 files changed, 47 insertions(+)
create mode 100644
Documentation/devicetree/bindings/iio/afe/current-sense-shunt.txt
diff --git a/Documentation/devicetree/bindings/iio/afe/current-sense-shunt.txt
b/Documentation/devicetree/bindings/iio/afe/current-sense-shunt.txt
new file mode 100644
index 000000000000..4d842aa85040
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/afe/current-sense-shunt.txt
@@ -0,0 +1,41 @@
+Current Sense Shunt
+===================
+
+When an io-channel measures the voltage over a current sense shunt,
+the interesting mesaurement is almost always the current through the
+shunt, not the voltage over it. This binding describes such a current
+sense circuit.
+
+Required properties:
+- compatible : "current-sense-shunt"
+- io-channels : Channel node of a voltage io-channel.
+- shunt-resistor-micro-ohms : The shunt resistance in microohms.
+
+Example:
+The system current is measured by measuring the voltage over a
+3.3 ohms shunt resistor.
+
+sysi {
+ compatible = "current-sense-shunt";
+ io-channels = <&tiadc 0>;
+
+ /* Divide the voltage by 3300000/1000000 (or 3.3) for the current. */
+ shunt-resistor-micro-ohms = <3300000>;
+};
+
+&i2c {
+ tiadc: adc@48 {
+ compatible = "ti,ads1015";
+ reg = <0x48>;
+ #io-channel-cells = <1>;
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ channel@0 { /* IN0,IN1 differential */
+ reg = <0>;
+ ti,gain = <1>;
+ ti,datarate = <4>;
+ };
+ };
+};
diff --git a/MAINTAINERS b/MAINTAINERS
index 36a28e979e9a..0f7bec878919 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6889,6 +6889,12 @@ F: drivers/staging/iio/
F: include/linux/iio/
F: tools/iio/
+IIO UNIT CONVERTER
+M: Peter Rosin <p...@axentia.se>
+L: linux-...@vger.kernel.org
+S: Maintained
+F: Documentation/devicetree/bindings/iio/afe/current-sense-shunt.txt
+
IKANOS/ADI EAGLE ADSL USB DRIVER
M: Matthieu Castet <castet.matth...@free.fr>
M: Stanislaw Gruszka <stf...@wp.pl>
--
2.11.0
