Re: [PATCH v3 16/19] dt-bindings: hwmon: (mr75203) add coefficient properties for the thermal equation

Rob Herring
2022-09-02T20:04:00Z

On Tue, Aug 30, 2022 at 07:22:09PM +0000, Eliav Farber wrote:
> Add optional temperature coefficient properties:
> *) moortec,ts-coeff-g
> *) moortec,ts-coeff-h
> *) moortec,ts-coeff-cal5
> *) moortec,ts-coeff-j
> If defined they shall be used instead of defaults.
>
> The coefficients were added to device tree on top of the series property
> (which can be used to select between series 5 and series 6), because
> coefficients can vary between product and product, and code defaults might
> not be accurate enough.
>
> Signed-off-by: Eliav Farber <farbere@amazon.com>
> ---
> V3 -> V2:
> - Add "moortec" prefix to property name.
>
> .../bindings/hwmon/moortec,mr75203.yaml | 33 +++++++++++++++++++
> 1 file changed, 33 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/hwmon/moortec,mr75203.yaml b/Documentation/devicetree/bindings/hwmon/moortec,mr75203.yaml
> index ec2dbe7da9c2..a92da6064285 100644
> --- a/Documentation/devicetree/bindings/hwmon/moortec,mr75203.yaml
> +++ b/Documentation/devicetree/bindings/hwmon/moortec,mr75203.yaml
> @@ -74,6 +74,37 @@ properties:
> default: 5
> $ref: /schemas/types.yaml#definitions/uint32
>
> + moortec,ts-coeff-g:
> + description:
> + G coefficient for temperature equation.
> + Value should be multiplied by factor 1000.

If you just multiply the values here, you can specify 'multipleOf: 1000'

Either way, some constraints would be nice. Or is 0 - 2^32 valid?

> + Default for series 5 = 60000
> + Default for series 6 = 57400
> + $ref: /schemas/types.yaml#/definitions/uint32
> +
> + moortec,ts-coeff-h:
> + description:
> + H coefficient for temperature equation.
> + Value should be multiplied by factor 1000.
> + Default for series 5 = 200000
> + Default for series 6 = 249400
> + $ref: /schemas/types.yaml#/definitions/uint32
> +
> + moortec,ts-coeff-cal5:
> + description:
> + cal5 coefficient for temperature equation (can't be 0).

minimum: 1

> + Default for series 5 = 4094
> + Default for series 6 = 4096
> + $ref: /schemas/types.yaml#/definitions/uint32
> +
> + moortec,ts-coeff-j:
> + description:
> + J coefficient for temperature equation.
> + Value should be multiplied by factor 1000.
> + Default for series 5 = -100
> + Default for series 6 = 0
> + $ref: /schemas/types.yaml#/definitions/int32
> +
> required:
> - compatible
> - reg
> @@ -97,5 +128,7 @@ examples:
> resets = <&rcu0 0x40 7>;
> moortec,vm-active-channels = <0x10 0x05>;
> moortec,vm-pre-scaler = <5 6>;
> + moortec,ts-coeff-g = <61400>;
> + moortec,ts-coeff-h = <253700>;
> #thermal-sensor-cells = <1>;
> };
> --
> 2.37.1
>
>