Re: [PATCH v7 4/9] spi: cs42l43: Use actual ACPI firmware node for chip selects

[Bartosz Golaszewski]

On Mon, Nov 24, 2025 at 5:58 PM Charles Keepax
<ckeepax@xxxxxxxxxxxxxxxxxxxxx> wrote:
>
> On Thu, Nov 20, 2025 at 02:23:59PM +0100, Bartosz Golaszewski wrote:
> > From: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>
> >
> > On some systems the cs42l43 has amplifiers attached to its SPI
> > controller that are not properly defined in ACPI. Currently
> > software nodes are added to support this case, however, the chip
> > selects for these devices are specified using a hack. A software
> > node is added with the same name as the pinctrl driver, as the
> > look up was name based, this allowed the GPIO look up to return
> > the pinctrl driver even though the swnode was not owned by it.
> > This was necessary as the swnodes did not support directly
> > linking to real firmware nodes.
> >
> > Since commit e5d527be7e69 ("gpio: swnode: don't use the swnode's
> > name as the key for GPIO lookup") changed the lookup to be
> > fwnode based this hack will no longer find the pinctrl driver,
> > resulting in the driver not probing. There is no pinctrl driver
> > attached to the swnode itself. But other patches did add support
> > for linking a swnode to a real fwnode node [1]. As such the hack
> > is no longer needed, so switch over to just passing the real
> > fwnode for the pinctrl property to avoid any issues.
> >
> > Link: https://lore.kernel.org/linux-gpio/20251106-reset-gpios-swnodes-v6-0-69aa852de9e4@xxxxxxxxxx/ [1]
> > Fixes: 439fbc97502a ("spi: cs42l43: Add bridged cs35l56 amplifiers")
> > Cc: stable+noautosel@xxxxxxxxxx # Don't backport, previous approach works, fix relies on swnode changes
>
> Just wanted to check what the thinking is on backports here. I
> see we have marked this as do not backport. Which I think is
> sensible the changes in the preceeding patches are a bit much for
> a backport. However, the patch has caused the regression has gone
> to a few stable branches (v6.17, v6.12):
>

I totally forgot about this having gone into stable.

> commit e5d527be7e69 ("gpio: swnode: don't use the swnode's name as the key for GPIO lookup")
>
> Are you guys ok if I send a revert for that patch to the stable
> branches it has gone to? It doesn't actually fix any bugs on
> those kernels, and we are starting to see issues coming in that I
> think are related to this:
>

Yes, definitely, please do. You can add:

Acked-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>

Bart