Re: [PATCH v2 2/3] dt-bindings: hwmon: Add binding for max6639

From: Krzysztof Kozlowski
Date: Tue Oct 11 2022 - 12:31:00 EST


On 11/10/2022 06:47, Naresh Solanki wrote:
> From: Marcello Sylvester Bauer <sylv@xxxxxxx>
>
> Add Devicetree binding documentation for Maxim MAX6639 temperature
> monitor with PWM fan-speed controller.
>
> Signed-off-by: Marcello Sylvester Bauer <sylv@xxxxxxx>
> Signed-off-by: Naresh Solanki <Naresh.Solanki@xxxxxxxxxxxxx>
> ---
> .../bindings/hwmon/maxim,max6639.yaml | 116 ++++++++++++++++++
> 1 file changed, 116 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/hwmon/maxim,max6639.yaml
>
> diff --git a/Documentation/devicetree/bindings/hwmon/maxim,max6639.yaml b/Documentation/devicetree/bindings/hwmon/maxim,max6639.yaml
> new file mode 100644
> index 000000000000..bbefb0a57ab3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/maxim,max6639.yaml
> @@ -0,0 +1,116 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +
> +$id: http://devicetree.org/schemas/hwmon/maxim,max6639.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Maxim max6639
> +
> +maintainers:
> + - Roland Stigge <stigge@xxxxxxxxx>
> +
> +description: |
> + The MAX6639 is a 2-channel temperature monitor with dual, automatic, PWM
> + fan-speed controller. It monitors its own temperature and one external
> + diode-connected transistor or the temperatures of two external diode-connected
> + transistors, typically available in CPUs, FPGAs, or GPUs.
> +
> + Datasheets:
> + https://datasheets.maximintegrated.com/en/ds/MAX6639-MAX6639F.pdf
> +
> +properties:
> + compatible:
> + enum:
> + - maxim,max6639
> +
> + reg:
> + maxItems: 1
> +
> + '#address-cells':
> + const: 1
> +
> + '#size-cells':
> + const: 0
> +
> +required:
> + - compatible
> + - reg
> +
> +patternProperties:
> + "^ot[0-1]_indication$":

No underscores in names.

> + type: boolean
> + default: false
> + description:
> + If true then enable OT pin indication.

Description copies the name of property. Not really useful. Describe
that it does.

Why this has 0 and 1 numbers? Isn't it connected with fan?

> +
> + "^therm[0-1]_indication$":
> + type: boolean
> + default: false
> + description:
> + If true then enable THERM pin indication.

Ditto

> +
> + "^fan@[0-1]$":

[01]
The same in other cases.

> + type: object
> + description: |
> + Represents the two fans and their specific configuration.
> +
> + $ref: fan-common.yaml#
> +
> + properties:
> + reg:
> + description: |
> + The fan number.
> + items:
> + minimum: 0
> + maximum: 1
> +
> + maxim,fan-spin-up:
> + type: boolean
> + description:
> + If true then whnever the fan starts up from zero drive, it

whenever
run spell-check

> + is driven with 100% duty cycle for 2s to ensure that it
> + starts.
> +
> + maxim,full-speed-on-therm:
> + type: boolean
> + description:
> + If true then force fan to full speed if THERM pin goes low.
> +
> + maxim,fanfail_indication:

No underscores

> + type: boolean
> + description:
> + If true then enable fanfail pin indication.

Missing blank line

> + required:
> + - reg
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + i2c {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + max6639@10 {

Node names should be generic.
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation

> + compatible = "maxim,max6639";
> + reg = <0x10>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + fan@0 {
> + reg = <0x0>;
> + pulses-per-revolution = <2>;
> + max-rpm = <4000>;
> + pwm-frequency = <25000>;
> + };
> +
> + fan@1 {
> + reg = <0x1>;
> + pulses-per-revolution = <2>;
> + max-rpm = <32000>;
> + pwm-frequency = <25000>;
> + };
> + };
> + };
> +...

Best regards,
Krzysztof