The platform I see this on does use device-tree and it does have a node for the ti,tmp451 device which uses the lm90 device. This platform uses the device-tree source arch/arm64/boot/dts/nvidia/tegra194-p2972-0000.dts and the tmp451 node is in arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi.
Interesting. It appears that the call to devm_thermal_zone_of_sensor_register()
in the hwmon core nevertheless returns -ENODEV which is not handled properly
in the hwmon core. I can see a number of reasons for this to happen:
- there is no devicetree node for the lm90 device
- there is no thermal-zones devicetree node
- there is no thermal zone entry in the thermal-zones node which matches
the sensor