Re: [PATCH v1 05/16] USB: ACPI: Use acpi_find_child_by_adr()

[Rafael J. Wysocki]

On Fri, Jun 10, 2022 at 8:47 AM Heikki Krogerus
<heikki.krogerus@xxxxxxxxxxxxxxx> wrote:
>
> On Thu, Jun 09, 2022 at 03:56:42PM +0200, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> >
> > Instead of walking the list of children of an ACPI device directly
> > in order to find the child matching a given bus address, use
> > acpi_find_child_by_adr() for this purpose.
> >
> > Apart from simplifying the code, this will help to eliminate the
> > children list head from struct acpi_device as it is redundant and it
> > is used in questionable ways in some places (in particular, locking is
> > needed for walking the list pointed to it safely, but it is often
> > missing).
> >
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> > ---
> >  drivers/usb/core/usb-acpi.c |    9 +--------
> >  1 file changed, 1 insertion(+), 8 deletions(-)
> >
> > Index: linux-pm/drivers/usb/core/usb-acpi.c
> > ===================================================================
> > --- linux-pm.orig/drivers/usb/core/usb-acpi.c
> > +++ linux-pm/drivers/usb/core/usb-acpi.c
> > @@ -127,17 +127,10 @@ out:
> >  static struct acpi_device *usb_acpi_find_port(struct acpi_device *parent,
> >                                             int raw)
> >  {
> > -     struct acpi_device *adev;
> > -
> >       if (!parent)
> >               return NULL;
> >
> > -     list_for_each_entry(adev, &parent->children, node) {
> > -             if (acpi_device_adr(adev) == raw)
> > -                     return adev;
> > -     }
> > -
> > -     return acpi_find_child_device(parent, raw, false);
> > +     return acpi_find_child_by_adr(parent, raw);
> >  }
> >
> >  static struct acpi_device *
>
> I think usb_acpi_find_port() can also be dropped now.

Yes, it can.

I'm dropping it in the new version of the patch to be posted.