Re: [PATCH v7 1/3] dt-bindings: mtd: Add Loongson-1 NAND Controller

[Keguang Zhang]

On Fri, Jun 7, 2024 at 5:33 AM Miquel Raynal <miquel.raynal@xxxxxxxxxxx> wrote:
>
> Hi,
>
> > > > > > +properties:
> > > > > > +  compatible:
> > > > > > +    oneOf:
> > > > > > +      - const: loongson,ls1b-nfc
> > > > >
> > > > > What is the rationale behind this choice? Seems like the b variant has
> > > > > two possible implementations and should always be preceded by a more
> > > > > specific compatible.
> > > > >
> > > > > As there is currently no description of this controller upstream, I
> > > > > would not care too much about any out-of-tree description and directly
> > > > > go for a clean description.
> > > > >
> > > > Excuse me, should I add a description for this property?
> > >
> > > No, description is not needed. But you are allowing the
> > > "loongson,ls1b-nfc" compatible alone, which I think is not relevant,
> > > unless you convince me it is :-)
> > >
> > "loongson,ls1b-nfc" itself is a specific implementation.
> > I was suggested to set up a fallback before.
> > https://lore.kernel.org/all/20231007-untapped-masses-01f80b7c13c7@spud/
> > Then "loongson,ls1b-nfc" became the fallback.
>
> You cannot allow 'the fallback', alone. But this is what you do above.
> Below description is fine. Just don't allow the ls1b-nfc compatible
> alone.
>
Sorry. I still don't get this.
According to https://lore.kernel.org/all/20221212163532.142533-2-krzysztof.kozlowski@xxxxxxxxxx/,
the generic fallback should not be used alone.
In contrast, the specific fallback has to be used alone, as I understand it.
If not, could you please show me the right way?
Thanks very much!

> Thanks,
> Miquèl



-- 
Best regards,

Keguang Zhang