Re: [PATCH] gpio: Revert regression in sysfs-gpio (gpiolib.c)

[Marcelo Roberto Jimenez <marcelo.jimenez@xxxxxxxxx>]

Hi Bart,

On Mon, Dec 20, 2021 at 11:57 AM Bartosz Golaszewski <brgl@xxxxxxxx> wrote:
>
> On Sat, Dec 18, 2021 at 7:28 AM Thorsten Leemhuis
> <regressions@xxxxxxxxxxxxx> wrote:
> >
> > [TLDR: I'm adding this regression to regzbot, the Linux kernel
> > regression tracking bot; most text you find below is compiled from a few
> > templates paragraphs some of you might have seen already.]
> >
> > On 17.12.21 16:35, Marcelo Roberto Jimenez wrote:
> > > Some GPIO lines have stopped working after the patch
> > > commit 2ab73c6d8323f ("gpio: Support GPIO controllers without pin-ranges")
> > >
> > > And this has supposedly been fixed in the following patches
> > > commit 89ad556b7f96a ("gpio: Avoid using pin ranges with !PINCTRL")
> > > commit 6dbbf84603961 ("gpiolib: Don't free if pin ranges are not defined")
> >
> > There seems to be a backstory here. Are there any entries and bug
> > trackers or earlier discussions everyone that looks into this should be
> > aware of?
> >
>
> Agreed with Thorsten. I'd like to first try to determine what's wrong
> before reverting those, as they are correct in theory but maybe the
> implementation missed something.
>
> Have you tried tracing the execution on your platform in order to see
> what the driver is doing?

Yes. The problem is that there is no list defined for the sysfs-gpio
interface. The driver will not perform pinctrl_gpio_request() and will
return zero (failure).

I don't know if this is the case to add something to a global DTD or
to fix it in the sysfs-gpio code.

> Bart

Regards,
Marcelo.