Hi Peter,
On Wed, Sep 22, 2021 at 9:53 AM Peter Rosin <peda@xxxxxxxxxx> wrote:
> I think that's because the "parent" channel (i.e. <&adc 4> in your case)
> is referring to a node that is not providing any iio channels at all.
>
> Just because you added "#io-channel-cells = <1>;" to that node, does not
> make it so. The driver has to support it as well.
I tried to use the same approach as in arch/arm/boot/dts/am5729-beagleboneai.dts
as per your suggestion:
--- a/arch/arm/boot/dts/imx6qdl-apalis.dtsi
+++ b/arch/arm/boot/dts/imx6qdl-apalis.dtsi
@@ -139,6 +139,23 @@
spdif-out;
status = "disabled";
};
+
+ adcmux: mux-controller {
+ compatible = "gpio-mux";
+ #mux-control-cells = <0>;
+ mux-gpios = <&gpio3 31 GPIO_ACTIVE_HIGH>,
+ <&gpio3 30 GPIO_ACTIVE_HIGH>,
+ <&gpio3 26 GPIO_ACTIVE_HIGH>;
+ };
+
+ adc-mux {
+ compatible = "io-channel-mux";
+ io-channels = <&adc0 4>;
+ io-channel-names = "parent";
+ mux-controls = <&adcmux>;
+ channels = "chan0", "chan1", "chan2", "chan3",
+ "chan4", "chan5", "chan6", "chan7";
+ };
};
&audmux {
@@ -362,6 +379,11 @@
compatible = "st,stmpe-adc";
/* forbid to use ADC channels 3-0 (touch) */
st,norequest-mask = <0x0F>;
+ adc0: iio-device {
+ #io-channel-cells = <1>;
+ iio-channels = <&adc0 4>, <&adc0 5>,
<&adc0 6>, <&adc0 7>;
+ iio-channel-names = "adc4", "adc5",
"adc6", "adc7";
+ };
};
};
};
but still the parent channel cannot be found.
So I don't have the DT properly describing the ADC to the mux relationship yet.
Thanks for your patience,
Fabio Estevam
