[PATCH 0/5] Make gpio_keys accept board descriptors

Dmitry Torokhov dmitry.torokhov at gmail.com
Wed Aug 26 12:12:22 EDT 2020


On Wed, Aug 26, 2020 at 05:35:43PM +0300, Heikki Krogerus wrote:
> On Wed, Aug 26, 2020 at 03:20:14PM +0200, Linus Walleij wrote:
> > Hi Dmitry,
> > 
> > On Sun, Nov 26, 2017 at 12:33 AM Dmitry Torokhov
> > <dmitry.torokhov at gmail.com> wrote:
> > > On Fri, Nov 24, 2017 at 10:30:40AM +0100, Linus Walleij wrote:
> > 
> > > > The goal I'm working toward is to rid the kernel of the global
> > > > GPIO numberspace.
> > > >
> > > > This means GPIO lines should be references by the local offset
> > > > on the GPIO chip.
> > > >
> > > > This patch set starts to move gpio_keys toward using GPIO
> > > > look-up tables instead of global GPIO numbers to find their
> > > > GPIOs.
> > > >
> > > > As an example I did (I think) the necessary patches to
> > > > convert DaVinci and i.MX to use this. There are several users
> > > > also x86 platform devices.
> > (...)
> > > I think this is a worthy goal, but I wonder if we could get static GPIO
> > > descriptors work with fwnode_get_named_gpiod() so we could retire the
> > > platform data parsing altogether. We'd need to extend static device
> > > properties to have notion of children though.
> > 
> > Do we have this now? I've looked at Heikki's et al work
> > on software nodes but I cannot see whether we are there now.
> > 
> > We have fwnode_create_software_node() and friends, but
> > I haven't seen if this can be used with input and GPIO descriptors
> > are still a bit on the side. I can create a lot of properties but
> > not really add a descriptor table as a software node as far as
> > I can tell. I'm also a bit lost on whether it will be possible
> > to get there sadly :/
> 
> I'm sorry but I'm not completely sure what is this about? Are software
> nodes still missing something that would prevent us from for example
> using them to describe the GPIO information exactly the same way it is
> described in DT? I don't know if that is what we want, but I'm just
> trying to understand what is still missing? Dmitry?

No, my changes to improve the fwnode handling of references have landed,
a while ago, so now I need to refresh the series of patches to gpiolib I
was working on around Plumbers time last year. Linus seemed mostly OK
with them, so it just a matter of finding time and picking this up
again.

Thanks.

-- 
Dmitry



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