Re: [PATCH] software node: allow referencing software nodes by name

[Bartosz Golaszewski]

On Thu, Mar 26, 2026 at 9:27 AM Andy Shevchenko
<andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
>
> On Wed, Mar 25, 2026 at 05:32:06PM +0100, Bartosz Golaszewski wrote:
> > On Tue, Mar 24, 2026 at 8:30 PM Dmitry Torokhov
> > <dmitry.torokhov@xxxxxxxxx> wrote:
> > >
> > > Please post the reworked version so we can review all the details. My
> > > concern was that it relies on notifier chains to notify when devices
> > > get registered and unregistered, and instead of matching node names you
> > > now need to somehow match device instances and software node instances,
> > > which again likely is done based on some name. This just piles on
> > > complexity where a simpler solution would be sufficient.
> >
> > I will post it. Hopefully before the end of the week. I want to cover
> > both OF nodes with paz00 as well as ACPI with android tablets. The
> > latter case will have to wait for devices because there's no way to
> > look up an ACPI node by name that I could idenfity (correct me if I'm
> > wrong).
>
> What do you need from ACPI exactly? The ACPI namespace in the OS is represented
> by set of ACPI handles, each of which is the object pointing out to some object
> in it. Any object in ACPI has a unique path. At any time, after parsing the
> ACPI table(s) into ACPI namespace we may get a handle based on the path.
>

DT is unflattened very early into the boot sequence. Is this the case
for ACPI tables as well? Knowing the name of the device (HID + index,
eg.: "INT33FF:00"), can I check if there's a corresponding ACPI node
(of_find_by_path/name() in DT parlance)?

Bart