Re: [PATCH 1/7] platform/x86: fujitsu-laptop: Define constants for FUNC operations

From: Darren Hart
Date: Mon Mar 05 2018 - 18:17:01 EST


On Sun, Mar 04, 2018 at 08:44:26PM +0100, MichaÅ KÄpieÅ wrote:
> > On Wed, Feb 28, 2018 at 06:08:52PM +0200, Andy Shevchenko wrote:
> > > On Tue, Feb 27, 2018 at 11:15 PM, Micha?? K??pie?? <kernel@xxxxxxxxxx> wrote:
> > > > Various functions exposed by the firmware through the FUNC interface
> > > > tend to use a consistent set of integers for denoting the type of
> > > > operation to be performed for a specified feature. Use named constants
> > > > instead of integers in each call_fext_func() invocation in order to more
> > > > clearly convey the intent of each call.
> > > >
> > > > Note that FUNC_FLAGS is a bit peculiar:
> > >
> > > > +/* FUNC interface - operations */
> > > > +#define OP_GET BIT(1)
> > > > +#define OP_GET_CAPS 0
> > > > +#define OP_GET_EVENTS BIT(0)
> > > > +#define OP_GET_EXT BIT(2)
> > > > +#define OP_SET BIT(0)
> > > > +#define OP_SET_EXT (BIT(2) | BIT(0))
> > >
> > > Hmm... this looks unordered a bit.
> >
> > It seems to be ordered alphabetically on the identifier. Andy, is it
> > preferred to order defines like this based on resolved numeric order?
>
> Just to expand on what Jonathan wrote above: if you take a peek at the
> end result of the patch series, you will notice a pattern: constants in
> each section are ordered alphabetically by their name. I wanted all
> sections to be consistently ordered. If you would rather have me order
> things by the bit index, sure, no problem, just please note that the
> order above is not accidental.

Hrm. In my experience it is more typical to order by value (bit), that's a
little less obvious when using the BIT()|BIT() macros though. So long as it's
consistent, I think that's what matters most.

--
Darren Hart
VMware Open Source Technology Center