Re: [PATCH 23/23] Documentation: gpio: add documentation for gpio-mockup

[Bartosz Golaszewski <brgl@xxxxxxxx>]

On Mon, Sep 7, 2020 at 5:23 PM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
>
> Hi Andy,
>
> On Mon, Sep 7, 2020 at 4:14 PM Andy Shevchenko
> <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
> > On Mon, Sep 07, 2020 at 03:49:23PM +0200, Bartosz Golaszewski wrote:
> > > On Mon, Sep 7, 2020 at 2:22 PM Greg Kroah-Hartman
> > > <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > > > On Mon, Sep 07, 2020 at 02:06:15PM +0200, Bartosz Golaszewski wrote:
> >
> > ...
> >
> > > > Yes it is.  Or at least until you fix all existing users so that if you
> > > > do change it, no one notices it happening :)
> > > >
> > >
> > > Then another question is: do we really want to commit to a stable ABI
> > > for a module we only use for testing purposes and which doesn't
> > > interact with any real hardware.
> > >
> > > Rewriting this module without any legacy cruft is tempting though. :)
> >
> > Another thought spoken loudly: maybe it can be unified with GPIO aggregator
> > code? In that case it makes sense.
>
> You want to aggregate GPIOs out of thin air?
>
> From DT, that would be something like
>
>     gpios = <&gpio1 2>, <0>, <0>, <&gpio2, 5>;
>
> ?
>
> For writing into ".../new_device", we could agree on something like "0"
> means not backed by an existing GPIO?
>

I'm really not sure this makes any sense. Why complicate an otherwise
elegant module that is gpio-aggregator with functionalities that
obviously don't belong here? I want to add various parameters that
would affect the way the simulated chips work - this really doesn't
need to go into the aggregator.

Bart