Re: [PATCH v2 05/16] usb: hub: Associate port@ fwnode with USB port device

[Heikki Krogerus <heikki.krogerus@linux.intel.com>]

On Thu, Jun 11, 2026 at 11:35:13AM +0200, Bartosz Golaszewski wrote:
> On Thu, Jun 11, 2026 at 10:37 AM Andy Shevchenko
> <andriy.shevchenko@linux.intel.com> wrote:
> >
> > On Thu, Jun 11, 2026 at 04:20:58AM -0400, Bartosz Golaszewski wrote:
> > > On Wed, 10 Jun 2026 16:16:12 +0200, Andy Shevchenko
> > > <andriy.shevchenko@linux.intel.com> said:
> > > > On Wed, Jun 10, 2026 at 04:40:39PM +0800, Chen-Yu Tsai wrote:
> > > >> When a USB hub port is connected to a connector in a firmware node
> > > >> graph, the port itself has a node in the graph.
> > > >>
> > > >> Associate the port's firmware node with the USB port's device,
> > > >> usb_port::dev. This is used in later changes for the M.2 slot power
> > > >> sequencing provider to match against the requesting port.
> > > >
> > > > Okay, would this affect ACPI-based systems? if so, how?
> > > > Can you elaborate on that, please?
> > >
> > > Is it possible that there's an ACPI device node associated with the port like
> > > on some DT systems? I don't think so and there should be no impact IMO but I
> > > also don't know enough about ACPI.

There are device nodes for the USB ports in ACPI, and I think they get
always assigned in drivers/usb/core/usb-acpi.c.

> > The API is agnostic. There is a possibility to have software nodes associated
> > with the port. I think the best is to be sure that ACPI-aware people who are
> > experts in USB will check this (Heikki?).

I can't say what's the impact from this patch - I'm not an expert with
this side of USB. Is there a danger that we end up overwriting the
ACPI node for the port, or something else?

> Even if there is a software node - it shouldn't really matter. It will
> just be assigned to the port device.

thanks,

-- 
heikki