Re: [PATCH v2 1/2] dt-bindings: hwmon: pmbus: Add Analog Devices MAX16545/MAX16550 and Volterra VT7505

[Krzysztof Kozlowski]

On Thu, Jul 23, 2026 at 04:43:46PM +0000, Pradhan, Sanman wrote:
> From: Sanman Pradhan <psanman@xxxxxxxxxxx>
> 
> Add device tree binding documentation for the Analog Devices MAX16545 and
> MAX16550, and the Volterra VT7505 PMBus controllers.
> 
> Signed-off-by: Sanman Pradhan <psanman@xxxxxxxxxxx>
> ---
> Changes in v2:
> - Represent the severe-OCP deglitch filter in microseconds
>   (renamed to adi,ocp-severe-filter-us, values 0/1/2/10).
> 
>  .../bindings/hwmon/pmbus/adi,vt7505.yaml      | 82 +++++++++++++++++++
>  1 file changed, 82 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/hwmon/pmbus/adi,vt7505.yaml
> 
> diff --git a/Documentation/devicetree/bindings/hwmon/pmbus/adi,vt7505.yaml b/Documentation/devicetree/bindings/hwmon/pmbus/adi,vt7505.yaml
> new file mode 100644
> index 000000000000..6096e03cb80a
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/pmbus/adi,vt7505.yaml
> @@ -0,0 +1,82 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/hwmon/pmbus/adi,vt7505.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Analog Devices MAX16545/MAX16550 and Volterra VT7505 PMBus controllers
> +
> +maintainers:
> +  - Sanman Pradhan <psanman@xxxxxxxxxxx>
> +
> +description: |
> +  The Analog Devices MAX16545 and MAX16550, and the Volterra VT7505, are PMBus
> +  controllers that provide input/output voltage, input/output current,
> +  input power and temperature monitoring over the PMBus interface.
> +
> +  The MAX16545 uses the same programming model as the VT7505.
> +
> +  Datasheets:
> +  https://www.analog.com/media/en/technical-documentation/data-sheets/max16545b-max16545c.pdf
> +  https://www.analog.com/media/en/technical-documentation/data-sheets/max16550.pdf
> +
> +properties:
> +  compatible:
> +    oneOf:
> +      - enum:
> +          - adi,max16550
> +          - adi,vt7505
> +      - items:
> +          - const: adi,max16545
> +          - const: adi,vt7505
> +
> +  reg:
> +    maxItems: 1
> +
> +  adi,rload-ohms:
> +    description:
> +      Resistance in ohms of the external current-report resistor connected
> +      between the ILOAD pin and ground. It is used to scale the reported
> +      input and output current and power.

Isn't this the same as shunt resistor? There is a property: shunt-resistor-micro-ohms

> +    minimum: 1
> +    default: 4750
> +
> +  adi,ocp-severe-filter-us:
> +    description:
> +      Deglitch time, in microseconds, applied to the severe
> +      overcurrent-protection comparator, programmed into the
> +      MFR_CONFIG[15:14] field. The MAX16550 and VT7505 expose this field.
> +      On the MAX16545 the severe overcurrent delay is fixed and these bits
> +      are reserved.
> +    enum: [0, 1, 2, 10]
> +
> +required:
> +  - compatible
> +  - reg
> +
> +additionalProperties: false

Place it after "allOf:" block.

> +
> +allOf:
> +  # The severe OCP deglitch filter is fixed on the MAX16545, so the property
> +  # is only valid for the MAX16550 and VT7505.
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: adi,max16545
> +    then:
> +      properties:
> +        adi,ocp-severe-filter-us: false
> +
> +examples:
> +  - |
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        regulator@40 {
> +            compatible = "adi,vt7505";
> +            reg = <0x40>;
> +            adi,rload-ohms = <4750>;

Why no adi,ocp-severe-filter-us? There is no default, so how does the
hardware work?

Best regards,
Krzysztof