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From:   "Rafael J. Wysocki" <rafael@kernel.org>
Date:   Wed, 24 Aug 2022 20:34:28 +0200
Message-ID: <CAJZ5v0hm8NszTDsq-KJ4iO452WZ7C7u4ufbfTDdFXX9YnXmTDw@mail.gmail.com>
Subject: Re: [PATCH v2 5/5] ACPI: Drop parent field from struct acpi_device
To:     Andy Shevchenko <andy.shevchenko@gmail.com>
Cc:     "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Linux ACPI <linux-acpi@vger.kernel.org>,
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        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
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On Wed, Aug 24, 2022 at 8:23 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
>
> On Wed, Aug 24, 2022 at 8:13 PM Rafael J. Wysocki <rjw@rjwysocki.net> wrote:
> >
> > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> >
> > The parent field in struct acpi_device is, in fact, redundant,
> > because the dev.parent field in it effectively points to the same
> > object and it is used by the driver core.
> >
> > Accordingly, the parent field can be dropped from struct acpi_device
> > and for this purpose define acpi_dev_parent() to retrieve a parent
> > struct acpi_device pointer from the dev.parent field in struct
> > acpi_device.  Next, update all of the users of the parent field
> > in struct acpi_device to use acpi_dev_parent() instead of it and
> > drop it.
> >
> > While at it, drop the ACPI_IS_ROOT_DEVICE() macro that is only used
> > in one place in a confusing way.
> >
> > No intentional functional impact.
>
> Side note: Should we not convert these to use acpi_dev_parent()?
>
> https://elixir.bootlin.com/linux/v6.0-rc2/source/drivers/acpi/property.c#L1271
> https://elixir.bootlin.com/linux/v6.0-rc2/source/drivers/bus/hisi_lpc.c#L397

That can be done later, but thanks for the pointers!