Re: [PATCH v2 1/1] gpio: gpio-wcove: Fix GPIO control register offset calculation

[Alan Cox]

> So where can I get a handle on the people inside Intel who are obviously
> using ACPI GPIO class for shoehorning what we in the linux kernel call
> syscon or register bit misc access into the GPIO ACPI container just
> because they feel it is convenient?

It's a Windowsism and since Windows is the primary OS shipped the vendors
of client platforms do what is needed to make Windows work nicely.

> They need to invent a NEW ACPI four-character thing and call that
> "misc register bit" (_MRB?) or whatever and have it bind to syscon.
> This is not working.

Short of Microsoft adopting such a standard I don't think it would make
any difference (beyond making life worse because you'd have a new _MRB
that wasn't used by Windows so nobody ever tested).

> It feels like I am starting to maintain Intel's swiss army knife for misc
> register manipulation, and that should not be done by "virtual GPIO"
> because just look at it:

It's an ACPIism not an Intelism. I expect it's there on other vendors
devices and the same things will pop up as Windows/ARM platforms with
ACPI appear.

> General-purpose input/output - yeah that sounds like something
> going in/out of the system right?

It's become an ACPI interface for controlling all sorts of system state
in a way that works nicely in Windows. Rightly or wrongly that's the
situation and we are still the tail not the dog.

Alan