iio: hx711: add clock-frequency property in DT
Add clock-frequency property for hx711 ADC. This is the frequency of
PD_SCK.
After PD_SCK goes high DOUT is read just before PD_SCK goes down again.
This is necessary because of parasitic capacitance on the wiring.
Signed-off-by: Andreas Klinger <ak@it-klinger.de>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
diff --git a/Documentation/devicetree/bindings/iio/adc/avia-hx711.txt b/Documentation/devicetree/bindings/iio/adc/avia-hx711.txt
index b362940..2c1b67d 100644
--- a/Documentation/devicetree/bindings/iio/adc/avia-hx711.txt
+++ b/Documentation/devicetree/bindings/iio/adc/avia-hx711.txt
@@ -8,11 +8,17 @@
See Documentation/devicetree/bindings/gpio/gpio.txt
- avdd-supply: Definition of the regulator used as analog supply
+Optional properties:
+ - clock-frequency: Frequency of PD_SCK in Hz
+ Minimum value allowed is 10 kHz because of maximum
+ high time of 50 microseconds.
+
Example:
weight@0 {
compatible = "avia,hx711";
sck-gpios = <&gpio3 10 GPIO_ACTIVE_HIGH>;
dout-gpios = <&gpio0 7 GPIO_ACTIVE_HIGH>;
avdd-suppy = <&avdd>;
+ clock-frequency = <100000>;
};
