Re: [PATCH v7 1/2] dt-bindings: usb: dwc3: Document Renesas R-Car Gen5 DWC3 xHCI USB controller

[Marek Vasut]

On 9/7/26 7:43 PM, Conor Dooley wrote:

Hello Conor,

> > > > +unevaluatedProperties: false
> > >
> > > I said this elsewhere today, but this binding has lots of "distasteful"
> > > properties for things that should be determined from the compatible
> >
> > Which properties would those be ? (it seems
> > reg/clocks/interrupts/phys/power-domains/resets really need to be there as
> > separate properties, but maybe I am missing the point?)
>
> All the quirk properties is what I am talking about here. There's about
> 50 of them and I don't know if a single one should actually exist.

I cannot tell whether every one of them will ever be used or useful, but 
I also do not have a good argument to block most of them as they are 
tunables which apply to the DWC3 core itself.

I could make only the ones which are currently used available, but that 
would be confusing the implementers by suggesting that the other quirks 
are not applicable even if they might be ; and this would likely turn 
into an endless stream of schema updates, with random users enabling 
random quirks they just used. I don't think that would be helpful.

> > > , so I
> > > would appreciate it if you could use additionalProperties: false here
> > > cite the ones you need to use explicitly.
> >
> > May I ask, what exactly is the rule of thumb for additionalProperties:false
> > and unevaluatedProperties:false ? I seem to struggle with picking the right
> > one for a while now.
>
> I would say, if all properties being imported apply to you device, use
> unevaluated. If only some do, and there are some that will be
> problematic or confusing if used, then additionalProperties: false and
> citing the good ones explicit is clearer for users and prevents the bad
> combos.

Thank you for this clarification, I will make a note of it.