[PATCH] ARM: tegra: paz00: use software nodes to describe GPIOs for WiFi rfkill

[Chen-Yu Tsai]

On Sun, Feb 15, 2026 at 4:40 AM Marc Dietrich <marvin24 at gmx.de> wrote:
>
> Hallo Chen-Yu,
>
> On Sat, 14 Feb 2026, Chen-Yu Tsai wrote:
>
> > On Sat, Feb 14, 2026 at 10:27 PM Marc Dietrich <marvin24 at gmx.de> wrote:
> >>
> >> Hi Dimitry,
> >>
> >> On Wed, 11 Feb 2026, Dmitry Torokhov wrote:
> >>
> >>> Hi Thierry,
> >>>
> >>> On Fri, Jun 28, 2024 at 05:35:08PM +0200, Thierry Reding wrote:
> >>>> From: Thierry Reding <treding at nvidia.com>
> >>>>
> >>>>
> >>>> On Wed, 26 Jun 2024 21:46:13 -0700, Dmitry Torokhov wrote:
> >>>>> Complete conversion of the WiFi rfkill device to use device
> >>>>> properties/software nodes by utilizing PROPERTY_ENTRY_GPIO() instead of
> >>>>> a lookup table.
> >>>>>
> >>>>>
> >>>>
> >>>> Applied, thanks!
> >>>>
> >>>> [1/1] ARM: tegra: paz00: use software nodes to describe GPIOs for WiFi rfkill
> >>>>       commit: 47ac458bb229f8c4864081d173adbcfc55c34880
> >>>
> >>> Do you know by any chance why paz00 does not simply configure rfkill
> >>> switch via device tree? The driver (rfkill-gpio) seem to support device
> >>> tree...
> >>
> >> last time I tried this was rejected because the wifi chip is on the usb
> >> bus and "rfkill" should be a sub-function of this chip [1], but that was
> >> some time ago...
> >>
> >> Looking hard the schematics, the wifi chip does not have a gpio input as
> >> first thought. Rather it seems that the first gpio toggles a regulator
> >> which supplies the wifi module (m2 card) with power and the second gpio is
> >> just connected to the wifi LED.
> >>
> >> Not sure how to transfer this into dt, but I guess this would be the
> >> better solution.
> >
> > Then the first GPIO should probably just be described as a fixed regulator
> > feeding the USB controller that the M.2 module is connected to.
>
> I think that is what rfkill-gpio is for, so the proposal of
> Dimitry looks fine, execpt for the reset-gpio, aka LED which is
> already included in the dt (but maybe with the wrong gpio).

I did that some years ago and was rejected. It was for SDIO, not USB
though.

Note that if the wireless driver also registers an rfkill device, you
would end up with two rfkill devices in the system, and with slightly
different behavior.

One would just disable the radio portion of the WiFi device, while the
other would cause the WiFi device to disappear.


ChenYu

> I will give it a try on real HW and report back.
>
> Thanks!
>
> Marc