[PATCH v1 4/4] dt-bindings: iio: adc: ad7949: add adi,reference-source

[Liam Beguin <liambeguin@gmail.com>]

From: Liam Beguin <lvb@xiphos.com>

Add bindings documentation for the adi,reference-source property.
This property is required to properly configure the ADC sample request
based on which reference source should be used for the calculation.

Signed-off-by: Liam Beguin <lvb@xiphos.com>
---
 .../bindings/iio/adc/adi,ad7949.yaml          | 22 +++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7949.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7949.yaml
index 9b56bd4d5510..3f4629281cc8 100644
--- a/Documentation/devicetree/bindings/iio/adc/adi,ad7949.yaml
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7949.yaml
@@ -35,6 +35,28 @@ properties:
   "#io-channel-cells":
     const: 1
 
+  adi,reference-select:
+    allOf:
+      - $ref: /schemas/types.yaml#/definitions/uint32
+      - enum: [0, 1, 2, 3, 6, 7]
+
+    default: 7
+    description: |
+      Select the reference voltage source to use when converting samples.
+      Acceptable values are:
+      - 0: Internal reference and temperature sensor enabled.
+           Vref=2.5V, buffered output
+      - 1: Internal reference and temperature sensor enabled.
+           Vref=4.096V, buffered output
+      - 2: Use external reference, temperature sensor enabled.
+           Internal buffer disabled
+      - 3: Use external reference, internal buffer and temperature sensor
+           enabled.
+      - 6: Use external reference, internal buffer and temperature sensor
+           disabled.
+      - 7: Use external reference, internal buffer enabled.
+           Internal reference and temperature sensor disabled.
+
 required:
   - compatible
   - reg
-- 
2.30.1.489.g328c10930387