Re: [PATCH v6 1/2] dt-bindings: pwm: dwc: add optional reset
From: Krzysztof Kozlowski
Date: Thu Apr 30 2026 - 06:53:22 EST
On 29/04/2026 11:30, Xuyang Dong wrote:
>>>>>
>>>>> +allOf:
>>>>> + - $ref: pwm.yaml#
>>>>> +
>>>>> + - if:
>>>>> + properties:
>>>>> + compatible:
>>>>> + contains:
>>>>> + const: eswin,eic7700-pwm
>>>>
>>>> Same problem as v3 which I commented. I do not understand why your new
>>>> device has also 1 reset.
>>>>
>>>> Your commit msg MUST explain why 1 reset is valid.
>>>>
>>>
>>> Hi Krzysztof,
>>>
>>> Although the PWM IP supports two clock domains, each requiring a reset,
>>> the EIC7700 implementation uses the same clock domain for both clock
>>> signals. Therefore, the eic7700-pwm only supports one reset.
>>>
>>
>> If we speak about eic7700, explain why it has two resets now, according
>> to schema, even though you say it has not.
>>
>> But I was speaking about dw-apb-timers-pwm, which has one reset as well!
>> Why you are not having proper constraints? Please read writing bindings
>> document.
>>
>
> Hi Krzysztof,
>
> Let me clarify the reset signals.
> - snps,dw-apb-timers-pwm2: IP spec has 2 optional reset signals (one per
> clock domain), SoC vendor decides whether to wire them — so maxItems: 2,
> optional in required.
Two reset signals but what is exactly optional? Each of them? Only the
first? Binding does not allow the first to be optional.
> - eswin,eic7700-pwm: SoC physically ties both signals to one reset — so
> exactly 1, required.
Then two would not be right and you need to restrict that.
Krzysztof