On Fri, Sep 24, 2021 at 11:37:00AM -0400, Oskar Senft wrote:
> > > In many cases the channels are "shared" - we have 3 voltage, 3 current and 3
> > > power sensors but in fact they are not separate sensors but 3 channels
> > > each able to measure 3 different things and they may share some common
> > > properties in each channel (so current, voltage and power may be
> > > calculated bases on the same shunt resistor or correction factor). An
> > > example being adi,ltc2992. In those cases it doesn't make sense to have
> > > two levels as how would you describe the shared parent? Call it generic
> > > "channels"?
>
> So in that case (e.g. for the nct7802, see [1]) do we want just
> 1-level, maybe like this:
>
> nct7802@28 {
> compatible = "nuvoton,nct7802";
> reg = <0x28>;
>
> sensor@1 { /* RTD1 */
> reg = <0x1>;
> status = "okay";
> mode = "thermistor"; /* Any of "thermistor", "thermal-diode",
> "voltage" */
> };
>
> sensor@2 { /* RTD2 */
> reg = <0x2>;
> status = "okay";
> mode = "thermal-diode"; /* Any of "thermistor",
> "thermal-diode", "voltage" */
> };
>
> sensor@3 { /* RTD3 */
> reg = <0x3>;
> status = "okay";
> mode = "voltage"; /* Any of "thermistor", "voltage" */
> };
>
> sensor@4 { /* LTD */
> reg = <0x4>; /* using the same number as in sysfs */
Numbering in sysfs is not relevant here; the index should always start with 0.
> status = "okay";
> /* No mode configuration for LTD */
> };
> };
>
> In this example, RTD1, RTD2 and LTD would be temperature sensors and
> RTD3 would be a voltage sensor.
>
> Would that make more sense? Is the use of strings acceptable?
>
I don't think so. I am quite sure that rtd3 is still a temperature,
and I am not sure if other sensor types on that chip may need dt
configuration.
I have limited internet acces for the next week or so; I'll look
into this further after I am back.
Guenter
> Thanks
> Oskar.
>
> [1] https://lore.kernel.org/all/20210921004627.2786132-1-osk@xxxxxxxxxx/
