Re: [PATCH v2 2/2] dt-bindings: hwmon: pwm-fan: add retain-state-shutdown property
From: Krzysztof Kozlowski
Date: Wed Oct 30 2024 - 11:25:09 EST
On 28/10/2024 15:57, Akinobu Mita wrote:
>>>>
>>>> You described the desired Linux feature or behavior, not the actual
>>>> hardware. The bindings are about the latter, so instead you need to
>>>> rephrase the property and its description to match actual hardware
>>>> capabilities/features/configuration etc.
>>>
>>> Is this description okay?
>>> (Reused the description of retain-state-shutdown in leds-gpio.yaml)
>>>
>>> description:
>>> Retain the state of the PWM on shutdown. Useful in BMC systems, for
>>> example, when the BMC is rebooted while the host remains up, the fan
>>> will not stop.
>>
>> Nothing improved in the property. You still say what the system should
>> do. This is user-space choice, not DT.
>
> It seems better to implement it as a device attribute.
I don't know about that. To repeat: if you say what system is supposed
to be doing, it is a policy. Describe the hardware and its configuration
and maybe this would be suitable for DT.
Best regards,
Krzysztof