Re: [PATCH v4 11/13] pinctrl: meson: Replace custom code by gpiochip_node_count() call

From: Andy Shevchenko
Date: Thu Apr 14 2022 - 14:28:48 EST


On Thu, Apr 14, 2022 at 07:06:21PM +0300, Andy Shevchenko wrote:
> On Thu, Apr 14, 2022 at 6:32 PM Martin Blumenstingl
> <martin.blumenstingl@xxxxxxxxxxxxxx> wrote:
> > On Thu, Apr 14, 2022 at 3:51 PM Andy Shevchenko
> > <andy.shevchenko@xxxxxxxxx> wrote:
> > [...]
> > > > This patch landed in linux next-20220413 as commit 88834c75cae5
> > > > ("pinctrl: meson: Replace custom code by gpiochip_node_count() call").
> > > > Unfortunately it breaks booting of all my Amlogic-based test boards
> > > > (Odroid C4, N2, Khadas VIM3, VIM3l). MMC driver is no longer probed and
> > > > boards are unable to mount rootfs. Reverting this patch on top of
> > > > linux-next fixes the issue.
> > >
> > > Thank you for letting me know, I'll withdraw it and investigate.
> > If needed I can investigate further later today/tomorrow. I think the
> > problem is that our node name doesn't follow the .dts recommendation.
> >
> > For GXL (arch/arm64/boot/dts/amlogic/meson-gxl.dtsi) the GPIO
> > controller nodes are for example:
> > gpio: bank@4b0 {
> > ...
> > }
> > and
> > gpio_ao: bank@14 {
> > ...
> > }
> >
> > See also:
> > $ git grep -C6 gpio-controller arch/arm64/boot/dts/amlogic/*.dtsi
> >
> > Marek did not state which error he's getting but I suspect it fails
> > with "no gpio node found".
>
> Would be interesting to know that, yeah.
>
> The subtle difference between the patched and unpatched version is
> that the former uses only available nodes, it means that node is not
> available by some reason and then the error would be the one you
> guessed.

Looking into the difference between iterating via available nodes I have found
nothing suspicious. Your DTSes do not have status property, so it assumes the
node is available.

I'm quite puzzled what's going on there. Because I can't see what the logical
difference the patch brought in.

P.S. In any case it's withdrawn now and shouldn't appear in the next Linux
Next. But I would really appreciate more input on this.

--
With Best Regards,
Andy Shevchenko