On Sat, Oct 7, 2023 at 9:56 AM Andy Shevchenko
<andriy.shevchenko@xxxxxxxxx> wrote:
>
> On Fri, Oct 06, 2023 at 09:47:57PM +0200, Rafael J. Wysocki wrote:
> > On Fri, Oct 6, 2023 at 8:33 PM Michal Wilczynski
> > <michal.wilczynski@xxxxxxxxx> wrote:
>
> ...
>
> > > struct acpi_ac {
> > > struct power_supply *charger;
> > > struct power_supply_desc charger_desc;
> > > - struct acpi_device *device;
> > > + struct device *dev;
> >
> > I'm not convinced about this change.
> >
> > If I'm not mistaken, you only use the dev pointer above to get the
> > ACPI_COMPANION() of it, but the latter is already found in _probe(),
> > so it can be stored in struct acpi_ac for later use and then the dev
> > pointer in there will not be necessary any more.
> >
> > That will save you a bunch of ACPI_HANDLE() evaluations and there's
> > nothing wrong with using ac->device->handle. The patch will then
> > become almost trivial AFAICS and if you really need to get from ac to
> > the underlying platform device, a pointer to it can be added to struct
> > acpi_ac without removing the ACPI device pointer from it.
>
> The idea behind is to eliminate data duplication.
What data duplication exactly do you mean?
struct acpi_device *device is replaced with struct device *dev which
is the same size. The latter is then used to obtain a struct
acpi_device pointer. Why is it better to do this than to store the
struct acpi_device itself?
