Re: [PATCH] spi: spi-fsl-dspi: Add ACPI support

[Vladimir Oltean]

On Wed, Aug 26, 2020 at 09:45:47PM +0100, Mark Brown wrote:
> On Wed, Aug 26, 2020 at 11:41:08PM +0300, Vladimir Oltean wrote:
> > On Wed, Aug 26, 2020 at 10:34:04PM +0300, Andy Shevchenko wrote:
>
> > > Theoretically you may declare your HID in the same / similar way as
> > > PRP0001 and use same compatible strings and all other DT properties
> > > (when they make sense and not duplicate ACPI functionality).
> > > But better if ACPI people can tell you (I Cc'ed Rafael and ACPI
> > > mailing list) if it is gonna work.
>
> > Something doesn't look right about PRP0001, what's the catch?
>
> Microsoft decided not to implement support for it in Windows, it's
> essentially there for embedded style x86 platforms running Linux so they
> don't need to reimplement so many wheels and can just reuse existing DT
> bindings but it causes problems if you want to run Windows (and possibly
> some of the enterprise Linux distros, I can't remember if any of them
> had concerns about it) on the platform.

So if a silicon vendor doesn't care about Windows, what incentive does
it have to even register an official ACPI/PNP ID for its devices?