Re: [PATCH] gpio: mockup: use device properties instead of platform_data

From: Linus Walleij
Date: Tue Sep 25 2018 - 05:14:49 EST


On Tue, Sep 25, 2018 at 11:03 AM Mika Westerberg
<mika.westerberg@xxxxxxxxxxxxxxx> wrote:
> On Tue, Sep 25, 2018 at 10:53:30AM +0200, Linus Walleij wrote:
> > On Mon, Sep 24, 2018 at 9:35 AM Bartosz Golaszewski <brgl@xxxxxxxx> wrote:
> > > niedz., 23 wrz 2018 o 13:17 Bartosz Golaszewski <brgl@xxxxxxxx> napisaÅ(a):
> > > >
> > > > Some users want to introduce device tree support to the mockup driver.
> > > > Let's make it easier by switching to using generic device properties.
> > > > The driver stays compatible with previous use cases and after this
> > > > conversion there'll be no need to change the way probing of mockup
> > > > GPIO chips works.
> > > >
> > > > Tested with libgpiod test suite.
> > > >
> > > > Signed-off-by: Bartosz Golaszewski <brgl@xxxxxxxx>
> > (...)
> > > Linus, I just noticed that we either need to drop the check for
> > > -ENOENT or add an else that returns on any other error. I'll need to
> > > send a v2
> >
> > OK business as usual.
> >
> > > but I'll let you first tell me if you like the general idea.
> >
> > I don't know, I'm a bit ignorant about the idea, scope and
> > ambition with device properties.
> >
> > In my book this relates to the fwnode concept, but maybe
> > I'm wrong?
>
> I think you are right.
>
> > Mika, please fill us in here. The device properties in gpiolib
> > came in the patch
> > "gpio: Rework of_gpiochip_set_names() to use device property accessors"
>
> I'm not sure what to answer to be honest :) The idea behind that patch
> was that we would be able to use the same properties (DT properties,
> ACPI _DSD properties, or possibly built-in properties) to set names for
> GPIOs.

I guess it's a yes.

If Vincent use this as a basis for this DT (etc) probing it means we
can use the mockup GPIO driver for ACPI gpiochip prototyping as
well, which is a win-win.

Yours,
Linus Walleij