On Fri, Feb 12, 2021 at 5:19 PM Min Li <min.li...@renesas.com> wrote:
>
> >
> > Ah, so if this is for a PTP related driver, it should probably be
> > integrated into
> > the PTP subsystem rather than being a separate class.
> >
>
> I was trying to add these functions to PHC subsystem but was not accepted
> because the functions
> are specific to Renesas device and there is no place for those functions in
> PHC driver.
It would be useful to explain that in the patch description and link
to the original
discussion there. What exactly was the objection?
> > > > This tells me that you got the abstraction the wrong way: the common
> > > > files should not need to know anything about the specific
> > implementations.
> > > >
> > > > Instead, these should be in separate modules that call exported
> > > > functions from the common code.
> > > >
> > > >
> > >
> > > I got what you mean. But so far it only supports small set of
> > > functions, which is why I don't feet it is worth the effort to over
> > > abstract
> > things.
> >
> > Then maybe pick one of the two hardware variants and drop the abstraction
> > you have. You can then add more features before you add a proper
> > abstraction layer and then the second driver.
> >
>
> If I come up with a new file and move all the abstraction code there,
> does that work?
I think so, but it's more important to figure out a good user space
interface first. The ioctl interfaces should be written on a higher-level
abstraction, to ensure they can work with any hardware implementation
and are not specific to Renesas devices.
Can you describe on an abstract level how a user would use the
character device, and what they achieve by that?
Arnd
