From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andy Shevchenko <andy.shevchenko@gmail.com>
Date: Thu, 16 Apr 2020 13:34:13 +0300
Subject: [PATCH v5 14/29] acpi: Add a binding for ACPI settings in the
 device tree
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On Thu, Apr 16, 2020 at 11:27 AM Wolfgang Wallner
<wolfgang.wallner@br-automation.com> wrote:
> -----"Andy Shevchenko" <andy.shevchenko@gmail.com> schrieb: -----

[snip]

> >>  - acpi,compatible : ACPI devices may report a _HID or _CID of
> >"PRP0001", in
> >>     which case they are expected to provide a _DSD object with a
> >"compatible"
> >>     property.
> >
> >No, this is simple incorrect.
> >PRP0001 should not be mentioned at all. _DSD() as I said in the other
> >thread is orthogonal to the ACPI ID.
>
> Can "acpi,compatible" work in another way (without PRP0001)?
> Or do you mean that "acpi,compatible" can't work at all?

Oh yeah, it can't work, unfortunately.

So, compatible enumeration depends on PRP0001, which may not be
advertised for the products, while end users can do that on their own.
So, we may only generate ACPI excerpts for the devices that have an
official ID allocated.

> As far as I see PRP0001 would be the only way to pass a "compatible"
> property in ACPI.


-- 
With Best Regards,
Andy Shevchenko