Re: [PATCH v3 1/6] ACPI: scan: Extend acpi_walk_dep_device_list()

From: Andy Shevchenko
Date: Mon Mar 08 2021 - 08:58:17 EST


On Mon, Mar 08, 2021 at 02:36:27PM +0100, Rafael J. Wysocki wrote:
> On Sun, Mar 7, 2021 at 9:39 PM Andy Shevchenko
> <andy.shevchenko@xxxxxxxxx> wrote:
> > On Sun, Mar 7, 2021 at 3:36 PM Daniel Scally <djrscally@xxxxxxxxx> wrote:
> > > On 22/02/2021 13:34, Andy Shevchenko wrote:
> > > > On Mon, Feb 22, 2021 at 3:12 PM Daniel Scally <djrscally@xxxxxxxxx> wrote:
> > > >> The acpi_walk_dep_device_list() is not as generalisable as its name
> > > >> implies, serving only to decrement the dependency count for each
> > > >> dependent device of the input. Extend the function to instead accept
> > > >> a callback which can be applied to all the dependencies in acpi_dep_list.
> > > >> Replace all existing calls to the function with calls to a wrapper, passing
> > > >> a callback that applies the same dependency reduction.
> > > > The code looks okay to me, if it was the initial idea, feel free to add
> > > > Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>

...

> > > >> +void acpi_dev_flag_dependency_met(acpi_handle handle)

> > > > Since it's acpi_dev_* namespace, perhaps it should take struct acpi_device here?
> > >
> > > I can do this, but I avoided it because in most of the uses in the
> > > kernel currently there's no struct acpi_device, they're just passing
> > > ACPI_HANDLE(dev) instead, so I'd need to get the adev with
> > > ACPI_COMPANION() in each place. It didn't seem worth it...
>
> It may not even be possible sometimes, because that function may be
> called before creating all of the struct acpi_device objects (like in
> the case of deferred enumeration).
>
> > > but happy to
> > > do it if you'd prefer it that way?
> >
> > I see, let Rafael decide then. I'm not pushing here.
>
> Well, it's a matter of correctness.

Looking at your above comment it is indeed. Thanks for clarification!
But should we have acpi_dev_*() namespace for this function if it takes handle?

For time being nothing better than following comes to my mind:

__acpi_dev_flag_dependency_met() => __acpi_flag_device_dependency_met()
acpi_dev_flag_dependency_met() => acpi_flag_device_dependency_met()

--
With Best Regards,
Andy Shevchenko