Re: [PATCH v4 00/13] Add ACPI _DSD and unified device properties? support

Darren Hart
2014-10-21T21:50:09Z

On Sat, Oct 18, 2014 at 10:35:49AM +0200, Grant Likely wrote:
> On Wed, 15 Oct 2014 17:43:01 +0200
> , Darren Hart <dvhart@linux.intel.com>
> wrote:
> >
> >
> > On 10/15/14 17:17, Mark Rutland wrote:
> > > On Wed, Oct 15, 2014 at 03:46:39PM +0100, Darren Hart wrote:
> >
> > >> Mark, what would you propose we do differently to enable this driver to
> > >> be firmware-type agnostic?
> > >
> > > For this particular driver, all I'm asking for is that the
> > > "used-by-rtas" property is not moved over from of_find_property to
> > > device_get_property. It is irrelevant for all ACPI systems. Evidently my
> > > comment was unclear; I apologise for that.
> >
> > So my objection here is that by keeping the of_* terms in the driver we
> > are required to include of, although it does safely convert to returning
> > NULL if !CONFIG_OF I suppose.
>
> This shouldn't be that controversial. There will be things that only make
> sense for DT or only ACPI. Allowing the property to be processed when
> the other interface is being used may tempt firmware authors to use the
> property because it just happens to have a side effect that looks right
> to them.
>
> I don't see any problem with factoring out those bits into a function
> that is only called (or built) when the associated firmware interface is
> used. In these situations, the driver isn't 100% generic, so having
> small per-firmware hooks is absolutely okay and not a burden to
> maintain.

Hrm... well, I suppose this isn't a hill I want to die on. I can disagree and
commit here :-)

--
Darren Hart
Intel Open Source Technology Center