Re: [PATCH] gpio: Allow user to customise maximum number of GPIOs

From: Linus Walleij
Date: Fri Aug 26 2022 - 17:54:48 EST


On Fri, Aug 26, 2022 at 5:08 PM Christophe Leroy
<christophe.leroy@xxxxxxxxxx> wrote:
> Le 26/08/2022 à 15:49, Linus Walleij a écrit :
> > On Thu, Aug 25, 2022 at 4:00 PM Christophe Leroy
> > <christophe.leroy@xxxxxxxxxx> wrote:
> >
> >>> Christophe? Will you take a stab at it?
> >>
> >> Which patch should I write ?
> >
> > One that removes CONFIG_ARCH_HAS_NR_GPIO entirely, then
> > allocate bases for new GPIO chips from 0 and upward instead.
> > And then see what happens.
> >
>
> Ok, I can give it a try.

Nice!

> But what do I do with:
>
> drivers/gpio/gpio-aggregator.c: bitmap = bitmap_alloc(ARCH_NR_GPIOS,
> GFP_KERNEL);

That's just used locally in that driver to loop over the arguments to the
aggregator (from the file in sysfs). I would set some arbitrary root
like
#define AGGREGATOR_MAX_GPIOS 512
and just search/replace with that.

Yours,
Linus Walleij