Re: [PATCH 18/23] gpio: nomadik: support mobileye,eyeq5-gpio

[Théo Lebrun <theo.lebrun@xxxxxxxxxxx>]

Hello,

On Wed Feb 21, 2024 at 3:31 PM CET, Linus Walleij wrote:
> On Wed, Feb 14, 2024 at 5:24 PM Théo Lebrun <theo.lebrun@xxxxxxxxxxx> wrote:
>
> > We create a custom compatible for the STA2X11 IP block as integrated
> > into the Mobileye EyeQ5 platform. Its wake and alternate functions have
> > been disabled, we want to avoid touching those registers.
> >
> > We both do: (1) early return in functions that do not support the
> > platform, but with warnings, and (2) avoid calling those functions in
> > the first place.
> >
> > We ensure that pinctrl-nomadik is not used with this STA2X11 variant.
> >
> > Signed-off-by: Théo Lebrun <theo.lebrun@xxxxxxxxxxx>
>
> When testing I noticed that this patch breaks Ux500 (up until patch 17
> all works fine!).
>
> But I don't know why.
>
> Trying to figure it out...

Can I help in the debugging process?

Reading the code once again I'd guess
of_device_get_match_data(&gpio_pdev->dev) could be the root cause. We
are accessing match data for the GPIO device while probing the pinctrl
device. Maybe something isn't initialised properly yet? The rest looks
rather harmless, I've checked all conditional expressions.

Thanks,

--
Théo Lebrun, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com