On 9/16/21 12:53 PM, Oskar Senft wrote:
Ah, using the node name as indication for both sensor type and index ? SGTM, though we'd really need input from Rob. I guess one could also consider something more generic like "temperature-sensor@0", "voltage-sensor@0", and so on (instead of [mis-]using reg and a sensor-type field).Hmm, in that case, maybe we should just remove the "sensors" section. i2c { #address-cells = <1>; #size-cells = <0>; nct7802@28 { compatible = "nuvoton,nct7802"; reg = <0x28>; #address-cells = <1>; #size-cells = <0>; temperature-sensor@0 { /* LTD */ status = "okay"; label = "my local temperature"; }; temperature-sensor@1 { /* RTD1 */ status = "okay"; mode = <0x2>; /* 3904 transistor */ label = "other temperature"; }; temperature-sensor@3 { */ RTD3 */ status = "okay"; mode = <0x3>; /* thermal diode */ label = "3rd temperature"; }; }; };
I think there was a reason for "sensors", because there can be other bindings on the same level. Documentation/devicetree/bindings/hwmon/ltc2978.txt lists "regulators", for example. Where did you find the "sensors" example for ltc2978 ? I don't see it in the upstream kernel. Or was that derived from the official "regulators" bindings ?
Now, with "sensors" removed and everything at "top-level", we'll need to decide what to do if individual sensors are missing. I guess in that case I would just leave the affected sensors alone, i.e. neither configure nor disable them and instead read their status from HW. That way prior uses of the nct7802 in device trees will continue to behave as before as does the EEPROM-style configuration. I would like to focus on the implementation of the temperature-sensor entries for now (i.e. LTD, RTD1, RTD2, RTD3). Support for other sensor types could be added in a separate change. Would that be acceptable?
Yes, let's do that. I'd like us to keep the "sensors" subnode to have a clear association and differentiator to other sub-nodes such as "regulators". Open is if we can use "temperature-sensor@0" or if it would have to be a chip specific "ltd", but I think we can sort that out after suggesting an initial set of bindings to Rob. Thanks, Guenter
