On Fri, Sep 25, 2026 at 1:34 PM Danilo Krummrich <[email protected]> wrote: > > On Fri Sep 25, 2026 at 11:23 AM CEST, Rafael J. Wysocki wrote: > > From: Rafael J. Wysocki <[email protected]> > > > > The ACPI bus type does not allow drivers to be matched to devices, so > > the sysfs attributes related to drivers created for it are useless and > > their existence is confusing. > > > > Moreover, it is better to prevent drivers from being registered and > > looked up for a bus like that. > > > > To allow skipping the creation of those sysfs attributes and preventing > > driver registration and lookup for the ACPI bus type, introduce a > > "companion" bus type concept and add a special registration function > > for registering "companion" bus types, companion_bus_register(). > > > > The "drivers" directory under the ACPI bus type is still needed because > > there are versions of systemd that depend on it [1]. > > Maybe we should also add a brief note above kset_create_and_add("drivers", > ...) > why we retain the directory even if !use_drivers.
Yeah, won't hurt. I'll add one, or somebody will try to "fix" it in the future. > > Link: > > https://lore.kernel.org/linux-acpi/sn6pr02mb41575266a4580339e186e5d9d4...@sn6pr02mb4157.namprd02.prod.outlook.com/ > > [1] > > Signed-off-by: Rafael J. Wysocki <[email protected]> > > Reviewed-by: Danilo Krummrich <[email protected]> Thanks!
