Re: [PATCH v1 07/10] spi: pxa2xx: Provide num-cs for Sharp PDAs via device properties

Mark Brown
2024-03-26T20:03:02Z

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On Tue, Mar 26, 2024 at 08:50:04PM +0200, Andy Shevchenko wrote:
> On Tue, Mar 26, 2024 at 06:21:48PM +0000, Mark Brown wrote:
> > On Tue, Mar 26, 2024 at 08:07:57PM +0200, Andy Shevchenko wrote:

> > > Since driver can parse num-cs device property, replace platform data
> > > with this new approach.

> > But why?

> To be able to hide the header's contents from public.
> Should I update the commit message?

That would definitely help, but it's hard to see what the actual benefit
is here. It's removing platform data without doing the more difficult
bit where the platform gets converted to DT.

> > > +static const struct property_entry spitz_spi_properties[] = {
> > > + PROPERTY_ENTRY_U32("num-cs", 3),
> > > + { }
> > > +};

> > This is just platform data with less validation AFAICT.

> I'm not sure what validation you are expecting here. It should be done via

Well, the problem with swnode is that there's no validation to expect -
it's an inherent problem with swnode.

> DT schema ideally when the platform gets converted to DT. This change is
> an interim to that (at least it makes kernel side better). After the platform
> code may be gone completely or converted. If the latter happens, we got
> the validation back.

It is not clear to me that this makes the kernel side better, it just
seems to be rewriting the platform data for the sake of it. If it was
converting to DT there'd be some stuff from it being DT but this keeps
everything as in kernel as board files, just in a more complex form.

> In any case it's not worse than plain DT property handling in the kernel.
> The validation in that case is done elsewhere. Since the property is defined
> in board files the assumed validation is done during development/review
> stages. But OTOH for the legacy code we need not to touch the property
> provider more than once. We are _not_ expecting this to be spread.

I'm guessing you're just checking this by inspection though...

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