[PATCH v1 8/9] dt-bindings: iio: afe: add binding for temperature-sense-current

[Liam Beguin <liambeguin@gmail.com>]

From: Liam Beguin <lvb@xiphos.com>

An ADC is often used to measure other quantities indirectly. This
binding describe one cases, the measurement of a temperature through
a current sense amplifier (such as an AD590) and a sense resistor.

Signed-off-by: Liam Beguin <lvb@xiphos.com>
---
 .../iio/afe/temperature-sense-current.yaml    | 61 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 62 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/afe/temperature-sense-current.yaml

diff --git a/Documentation/devicetree/bindings/iio/afe/temperature-sense-current.yaml b/Documentation/devicetree/bindings/iio/afe/temperature-sense-current.yaml
new file mode 100644
index 000000000000..1bac74486102
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/afe/temperature-sense-current.yaml
@@ -0,0 +1,61 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/afe/temperature-sense-current.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Temperature Sense Current
+
+maintainers:
+  - Liam Beguin <lvb@xiphos.com>
+
+description: |
+  When an io-channel measures the output voltage for a temperature current
+  sense amplifier such as the AD950, the interesting measurement is almost
+  always the corresponding temperature, not the voltage output.
+  This binding describes such a circuit.
+
+properties:
+  compatible:
+    const: temperature-sense-current
+
+  io-channels:
+    maxItems: 1
+    description: |
+      Channel node of a voltage io-channel.
+
+  '#io-channel-cells':
+    const: 1
+
+  sense-resistor-ohms:
+    description: The sense resistance.
+
+  alpha-micro-amps-per-degree:
+    description: |
+      Linear output current gain of the temperature IC.
+
+  use-kelvin-scale:
+    type: boolean
+    description: |
+      Boolean indicating if alpha uses Kelvin degrees instead of Celsius.
+
+additionalProperties: false
+required:
+  - compatible
+  - io-channels
+  - sense-resistor-ohms
+  - alpha-micro-amps-per-degree
+
+examples:
+  - |
+    ad590: iio-rescale0 {
+        compatible = "temperature-sense-current";
+        #io-channel-cells = <1>;
+        io-channels = <&temp_adc 2>;
+
+        sense-resistor-ohms = <8060>;
+        use-kelvin-scale;
+        alpha-micro-amps-per-degree = <1>;
+    };
+
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index a7279af85adb..0eb7fcd94b66 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8721,6 +8721,7 @@ L:	linux-iio@vger.kernel.org
 S:	Maintained
 F:	Documentation/devicetree/bindings/iio/afe/current-sense-amplifier.yaml
 F:	Documentation/devicetree/bindings/iio/afe/current-sense-shunt.yaml
+F:	Documentation/devicetree/bindings/iio/afe/temperature-sense-current.yaml
 F:	Documentation/devicetree/bindings/iio/afe/temperature-sense-rtd.yaml
 F:	Documentation/devicetree/bindings/iio/afe/voltage-divider.yaml
 F:	drivers/iio/afe/iio-rescale.c
-- 
2.30.1.489.g328c10930387