AD5372 offset using iio

Hi, 

I'll check your concern with the Linux driver support team. 

If you're worried about the spike when changing the output range via the offset, what you can do is to make use of the /CLR function before setting the offset and output.

Best regards,

Ian

References can be set from device tree. See here: https://wiki.analog.com/resources/tools-software/linux-drivers/iio-dac/ad5360

-Travis

References can be set from device tree. See here: https://wiki.analog.com/resources/tools-software/linux-drivers/iio-dac/ad5360

-Travis

Thank you Ian and Travis.  Could you clarify on how this is accomplished in the device tree?  Matches for string "offset" in the page you shared are limited to the sysfs sections.  I'm attaching my working device tree.

/dts-v1/;
/plugin/;

/ {
        compatible = "brcm,bcm2711";
        fragment@0 {
                target-path = "/";
                __overlay__ {
                        vref0: fixedregulator@0 {
                                compatible = "regulator-fixed";
                                regulator-name = "fixed-supply";
                                regulator-min-microvolt = <5000000>;
                                regulator-max-microvolt = <5000000>;
                                regulator-boot-on;
                        };
                        vref1: fixedregulator@1 {
                                compatible = "regulator-fixed";
                                regulator-name = "fixed-supply";
                                regulator-min-microvolt = <5000000>;
                                regulator-max-microvolt = <5000000>;
                                regulator-boot-on;
                        };
                };
        };

        fragment@1 {
                target = <&spi0>;
                __overlay__ {
                        #address-cells = <1>;
                        #size-cells = <0>;
                        status = "okay";

                        ad5372@0{
                                compatible = "adi,ad5372";
                                reg = <0>;
                                spi-max-frequency = <100000>;
                                spi-cpha;
                                vref0-supply = <&vref0>;
                                vref1-supply = <&vref1>;
                        };
                };
        };
};

Hi,

You can only change the offset through sysfs attributes. There is no property that you can set in the device tree to change it when the part it is started.

This does not mean that you can't add things to the driver that fit your needs. There are drivers that read some configurations from the device tree. Here is one example:

https://github.com/analogdevicesinc/linux/blob/master/drivers/iio/dac/ad5770r.c#L572-L573https://github.com/analogdevicesinc/linux/blob/rpi-5.4.y/Documentation/devicetree/bindings/iio/dac/adi,ad5770r.yaml#L151

Hope this helps with your efforts.

Regards,

Mircea