Re: [PATCH v2 2/3] dt-bindings: hwmon: Add Microchip EMC2101 support

From: Krzysztof Kozlowski
Date: Wed Jul 02 2025 - 03:16:18 EST


On Tue, Jul 01, 2025 at 08:12:27PM +0200, Álvaro Fernández Rojas wrote:
> Introduce yaml schema for Microchip emc2101 pwm fan controller with
> temperature monitoring.
>
> Signed-off-by: Álvaro Fernández Rojas <noltari@xxxxxxxxx>
> ---
> .../bindings/hwmon/microchip,emc2101.yaml | 79 +++++++++++++++++++
> 1 file changed, 79 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/hwmon/microchip,emc2101.yaml
>
> v2: add missing properties.
>
> diff --git a/Documentation/devicetree/bindings/hwmon/microchip,emc2101.yaml b/Documentation/devicetree/bindings/hwmon/microchip,emc2101.yaml
> new file mode 100644
> index 000000000000..0966559d373e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/microchip,emc2101.yaml
> @@ -0,0 +1,79 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/hwmon/microchip,emc2101.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Microchip EMC2101 SMBus compliant PWM fan controller
> +
> +maintainers:
> + - Álvaro Fernández Rojas <noltari@xxxxxxxxx>
> +
> +description:
> + Microchip EMC2101 pwm controller which supports up to 1 fan, 1 internal
> + temperature sensor, 1 external temperature sensor and an 8 entry look
> + up table to create a programmable temperature response.
> +
> +properties:
> + compatible:
> + enum:
> + - microchip,emc2101
> + - microchip,emc2101-r

Nothing in description explains what 'r' is.

> +
> + reg:
> + maxItems: 1
> +
> + '#address-cells':
> + const: 1
> +
> + '#size-cells':
> + const: 0
> +
> + '#pwm-cells':
> + const: 2
> + description: |
> + Number of cells in a PWM specifier.
> + - cell 0: The PWM frequency
> + - cell 1: The PWM polarity: 0 or PWM_POLARITY_INVERTED
> +
> +patternProperties:
> + '^fan@0$':

This is just 'fan', not a pattern. See other bidnings.

> + $ref: fan-common.yaml#
> + unevaluatedProperties: false
> + properties:
> + reg:
> + description:
> + The fan number used to determine the associated PWM channel.

I can tell you: 0. Cannot be any other PWM channel.

> + maxItems: 1
> +
> + required:
> + - reg
> +
> +required:
> + - compatible
> + - reg

Best regards,
Krzysztof