Re: [PATCH v2] spi: cs42l43: Use actual ACPI firmware node for chip selects

From: Bartosz Golaszewski

Date: Thu Nov 20 2025 - 07:28:09 EST


On Thu, Nov 20, 2025 at 12:21 PM Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> wrote:
>
> On Do, 2025-11-20 at 10:59 +0000, Charles Keepax wrote:
> > 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")
> > Fixes: e5d527be7e69 ("gpio: swnode: don't use the swnode's name as the key for GPIO lookup")
> > Signed-off-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>
> > ---
> >
> > IMPORTANT NOTE: This depends both functionally and build wise on the
> > linked series from Bart, it probably makes sense for him to pull the
> > patch into his series.
>
> When included in the reset-gpios-swnodes series, will this need either
> a noautosel or prerequisite marker to avoid it being picked up into
> stable without the reset of the series?
>

Good point. Also: the Fixes: e5d527be7e69 ("gpio: swnode: don't use
the swnode's name as the key for GPIO lookup") tag needs to be removed
as this will go before this patch.

In any case, looks good to me now:

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

Mark: can you Ack it and Philipp will include it in the immutable
branch with the swnode series[1] I will resend?

Bart

[1] https://lore.kernel.org/all/20251106-reset-gpios-swnodes-v6-0-69aa852de9e4@xxxxxxxxxx/