Adding optional parameter to AD7949 to specify the source for the
reference voltage signal. Default value is maintained with option '3' to
match previous version of driver.
Signed-off-by: Adam Michaelis <adam.michaelis@xxxxxxxxxxxxxxxxxxx>
---
V2:
- Add some defines to reduce use of magic numbers.
V3:
- Re-think usage of device tree parameter to focus on the
actual reference sources instead of the raw hardware
configuration.
---
.../devicetree/bindings/iio/adc/ad7949.txt | 21 +++++++++++++++++++--
1 file changed, 19 insertions(+), 2 deletions(-)
diff --git a/Documentation/devicetree/bindings/iio/adc/ad7949.txt b/Documentation/devicetree/bindings/iio/adc/ad7949.txt
index c7f5057356b1..e5152335c761 100644
--- a/Documentation/devicetree/bindings/iio/adc/ad7949.txt
+++ b/Documentation/devicetree/bindings/iio/adc/ad7949.txt
@@ -6,11 +6,28 @@ Required properties:
* "adi,ad7682"
* "adi,ad7689"
- reg: spi chip select number for the device
- - vref-supply: The regulator supply for ADC reference voltage
-Example:
+Optional properties:
+ - adi,reference-select: Select the reference voltage source to use
+ when converting the input voltages. Valid values are:
+ 0: Internal 2.5V reference;
+ 1: Internal 4.096V reference;
+ 2: External REF reference;
+ 3: External REFIN reference (default);
+ - vref-supply: The regulator supply for external ADC reference voltage.
+ Required if one of the external references is selected by
+ 'adi,reference-select'.
+
+Examples:
adc@0 {
compatible = "adi,ad7949";
reg = <0>;
+ adi,reference-select = <2>;
vref-supply = <&vdd_supply>;
};
+
+adc@0 {
+ compatible = "adi,ad7949";
+ reg = <0>;
+ adi,reference-select = <0>;
+};
--
1.9.1
