Re: [PATCH 1/2] PM / OPP: compatible is an optional property

From: Rob Herring
Date: Fri Sep 23 2016 - 15:55:20 EST


On Fri, Sep 23, 2016 at 10:45:26AM +0530, Viresh Kumar wrote:
> On 22-09-16, 12:24, Stephen Boyd wrote:
> > On 09/21/2016 02:32 AM, Viresh Kumar wrote:
> > > It was never compulsory to have a compatible string in the OPP table.
> > > Fix the documentation to mark it optional.
> > >

NAK.

> > > Also update its description a bit.
> > >
> > > Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> > > ---
> >
> > Why? I'd prefer the compatible string to be required so we know what
> > sort of node it is.

Agreed.

> Okay, the code doesn't have any checks for it then and that needs to be fixed.

Why? The kernel is not a DT validator.

> Just for my clarity, for platforms with special OPP bindings and so a different
> compatible string like: "operating-points-v2-XYZ", should the compatible string
> contain both "operating-points-v2" and the above one? It would be easier to
> check for "operating-points-v2" in that case from core code.

That would imply operating-points-v2-XYZ has extra properties or is
different in some way. If an OS only understanding operating-points-v2
will work, then yes it should have both. If not, then no.

Rob