Re: [PATCH v3 01/10] Add auxiliary bus support

Dan Williams
2020-11-05T22:01:02Z

On Thu, Nov 5, 2020 at 11:28 AM Ertman, David M
<david.m.ertman@intel.com> wrote:
[..]
> > > Each auxiliary_device represents a part of its parent
> > > +functionality. The generic behavior can be extended and specialized as
> > needed
> > > +by encapsulating an auxiliary_device within other domain-specific
> > structures and
> > > +the use of .ops callbacks. Devices on the auxiliary bus do not share any
> > > +structures and the use of a communication channel with the parent is
> > > +domain-specific.
> >
> > Should there be any guidance here on when to use ops and when to just
> > export functions from parent driver to child. EXPORT_SYMBOL_NS() seems
> > a perfect fit for publishing shared routines between parent and child.
> >
>
> I would leave this up the driver writers to determine what is best for them.

I think there is a pathological case that can be avoided with a
statement like the following:

"Note that ops are intended as a way to augment instance behavior
within a class of auxiliary devices, it is not the mechanism for
exporting common infrastructure from the parent. Consider
EXPORT_SYMBOL_NS() to convey infrastructure from the parent module to
the auxiliary module(s)."

As for your other dispositions of the feedback, looks good to me.