Re: [PATCH v3 2/6] ACPI / x86: Consolidate Apple DMI checks

[Darren Hart <dvhart@infradead.org>]

On Thu, Jul 20, 2017 at 04:49:48PM +0200, Rafael Wysocki wrote:
> On Thursday, July 20, 2017 05:33:43 PM Andy Shevchenko wrote:
> > On Thu, 2017-07-20 at 16:27 +0200, Rafael J. Wysocki wrote:
> > > On Thu, Jul 20, 2017 at 4:03 PM, Lukas Wunner <lukas@wunner.de> wrote:
> > > > On Sat, Jul 15, 2017 at 12:03:31AM +0200, Rafael J. Wysocki wrote:
> > > > > On Friday, July 14, 2017 12:36:19 AM Lukas Wunner wrote:
> > > > > > 
> > 
> > 
> > > > I guess I could introduce a new <linux/apple.h> but I hate the
> > > > insane
> > > > proliferation of additional files in include/linux/.
> > > 
> > > There is include/linux/platform_data/x86/ so maybe put it in there?
> > 
> > Just suggested the same :-)

Yes please, this is precisely why we created this directory.

> > 
> > > >  I could merge the contents of apple_bl.h and apple-gmux.h into that
> > > > new header to
> > > > reduce the number of files a bit.
> > > > 
> > > > Struggling to find a solution that's nice and clean.  Any ideas?
> > > 
> > > I guess you still want it to work if someone configures the kernel
> > > without CONFIG_ACPI, although that's slightly debatable, so the
> > > variable should be defined somewhere in the arch code I suppose.
> > > 
> > > I also guess you could add something like arch/x86/platform/apple/ and
> > > put the checks and the variable in there (in which case I'd call it
> > > x86_apple_machine or similar).
> > 
> > I'm not sure if we can use drivers/platform/x86 for this, either agreed
> > way is fine to me.
> 
> No, because of the ACPI involvement.  That needs to go under arch/ IMO.

We have an example, silead_dmi.c, which extracts properties based on the DMI
match, and adds them to the i2c client device. While I suppose we could do
something like this, the drivers affected are really not "platform drivers", but
rather common drivers with platform specific properties. I concur with Rafael.

-- 
Darren Hart
VMware Open Source Technology Center