I've been spending a few days trying to get this kernel module hooked up properly, and I'm running out of options on the software front.
Here is the output from the command line. I get "Invalid argument" for scale, and "Input/Output Error" for all the adc lines except voltage0 returns 0 but that line isn't hooked up to anything.
:~# cat /sys/bus/iio/devices/iio\:device0/name ad7904 :~# cat /sys/bus/iio/devices/iio\:device0/in_voltage_scale cat: '/sys/bus/iio/devices/iio:device0/in_voltage_scale': Invalid argument :~# cat /sys/bus/iio/devices/iio\:device0/ buffer/ dev in_voltage1_raw in_voltage3_raw name power/ subsystem/ uevent current_timestamp_clock in_voltage0_raw in_voltage2_raw in_voltage_scale of_node/ scan_elements/ trigger/ :~# cat /sys/bus/iio/devices/iio\:device0/in_voltage0_raw 0 :~# cat /sys/bus/iio/devices/iio\:device0/in_voltage1_raw cat: '/sys/bus/iio/devices/iio:device0/in_voltage1_raw': Input/output error :~# cat /sys/bus/iio/devices/iio\:device0/in_voltage2_raw cat: '/sys/bus/iio/devices/iio:device0/in_voltage2_raw': Input/output error :~# cat /sys/bus/iio/devices/iio\:device0/in_voltage3_raw cat: '/sys/bus/iio/devices/iio:device0/in_voltage3_raw': Input/output error
This is my device tree:
&quad_spi {
#address-cells = <2>;
#size-cells = <0>;
gpiom2: gpio@0 {
compatible = "microchip,mcp23s17";
gpio-controller;
#gpio-cells = <2>;
microchip,spi-present-mask = <0x02>;
reg = <0>;
spi-max-frequency = <1000000>;
};
adc_supply: fixedregulator {
compatible = "regulator-fixed";
regulator-name = "fixed-supply";
regulator-min-microvolt = <3300000>;
regulator-max-microvolt = <3300000>;
};
adc_vref: fixedregulator {
compatible = "regulator-fixed";
regulator-name = "fixed-supply";
regulator-min-microvolt = <2500000>;
regulator-max-microvolt = <2500000>;
};
ad7904: ad7904@1 {
compatible = "adi,ad7904";
reg = <1>;
spi-max-frequency = <1000000>;
spi-cpha;
spi-cpol;
vcc-supply = <&adc_supply>;
vref-supply = <&adc_vref>;
};
};
This is my first time dealing with device tree. The gpioe works already and this ADC is on the same spi bus.
The AD7904 uses the AD7923 driver, but there is no documentation for this one, only a git source. I've been looking at other drivers similar and trying to make the device tree properly.
Any and all advice would be appreciated. I'm asking our EE if there is a line I can probe easily for chip-select and will update on whether its toggling.
