Re: [PATCH v3 1/2] dt-bindings: hwmon: Add LTC4282 bindings

["Nuno Sá" <noname.nuno@gmail.com>]

On Tue, 2023-12-05 at 16:18 +0000, Conor Dooley wrote:
> On Tue, Dec 05, 2023 at 04:22:55PM +0100, Nuno Sa via B4 Relay wrote:
> 
> > +  adi,overvoltage-dividers:
> > +    description: |
> > +      Select which dividers to use for VDD Overvoltage detection. Note that
> > +      when the internal dividers are used the threshold is referenced to VDD.
> > +      The percentages in the datasheet are misleading since the actual values
> > +      to look for are in the "Absolute Maximum Ratings" table in the
> > +      "Comparator Inputs" section. In there there's a line for each of the 5%,
> > +      10% and 15% settings with the actual min, typical and max tolerances.
> > +    $ref: /schemas/types.yaml#/definitions/string
> > +    enum: [external, vdd_5_percent, vdd_10_percent, vdd_15_percent]
> > +
> > +  adi,undervoltage-dividers:
> > +    description: |
> > +      Select which dividers to use for VDD Overvoltage detection. Note that
> > +      when the internal dividers are used the threshold is referenced to VDD.
> > +      The percentages in the datasheet are misleading since the actual values
> > +      to look for are in the "Absolute Maximum Ratings" table in the
> > +      "Comparator Inputs" section. In there there's a line for each of the 5%,
> > +      10% and 15% settings with the actual min, typical and max tolerances.
> > +    $ref: /schemas/types.yaml#/definitions/string
> > +    enum: [external, vdd_5_percent, vdd_10_percent, vdd_15_percent]
> 
> > +  adi,gpio1-mode:
> > +    description: Defines the function of the Pin. It can indicate that power is
> > +      good (PULL the pin low when power is not good) or that power is bad (Go
> > +      into high-z when power is not good).
> > +    $ref: /schemas/types.yaml#/definitions/string
> > +    enum: [power_bad, power_good]
> > +
> > +  adi,gpio2-mode:
> > +    description: Defines the function of the Pin. It can be set as the input for
> > +      the ADC or indicating that the MOSFET is in stress (dissipating power).
> > +    $ref: /schemas/types.yaml#/definitions/string
> > +    enum: [adc_input, stress_fet]
> 
> None of these properties have a default nor are required.
> What happens when they are omitted?
> 

Yeah, they get the power on reset default values (or whatever is in eeprom but that's
not the typical usecase). I'll add a default for all these properties. Your question
already made me realize something I need to fix for v4. For some reason, I thought
gpio3 was the default pin to be muxed into the ADC (and hence monitored by hwmon) but
I realized that gpio2 is the default one. Hence, I need a boolean property to allow
for users to mux gpio3 instead of gpio2.

- Nuno Sá