Re: [PATCH v1] ACPI: bus: Drop two fields from struct acpi_device_pnp

[Rafael J. Wysocki (Intel)]

On Tue, Sep 1, 2026 at 9:45 AM Andy Shevchenko
<andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
>
> On Mon, Aug 31, 2026 at 10:07:10PM +0200, Rafael J. Wysocki wrote:
>
> > There are two fields in struct acpi_device_pnp, device_name and
> > device_class, that were supposed to be populated and used by device
> > drivers, but they have never been used consistently and now they
> > are only set for the bus object in acpi_set_pnp_ids() (and never
> > read afterward).
> >
> > Drop them along with all of the associated symbols except for
> > MAX_ACPI_CLASS_NAME_LEN and the acpi_device_class typedef that
> > are used by the ACPI netlink messaging code.  Move those two
> > definitions closer to the struct acpi_bus_event that refers to
> > the acpi_device_class type.
>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
>
> ...
>
> > +#define MAX_ACPI_CLASS_NAME_LEN              20
> > +typedef char acpi_device_class[MAX_ACPI_CLASS_NAME_LEN];
>
> Are you planning to use this in some future code?
>
> >  struct acpi_bus_event {
> >       struct list_head node;
> >       acpi_device_class device_class;
>
> Otherwise I would go with complete replacement of the above to simple
>
>         char acpi_device_class[20];
>
> here.

This is in use in the Thinkpad driver.

It might be replaced with something else, but that would be a separate patch.