port-i386/43659: acpiwmi(4) should pass EC operation regions to acpiec(4)

[Jukka Ruohonen <jruohonen%iki.fi@localhost>]

>Number:         43659
>Category:       port-i386
>Synopsis:       acpiwmi(4) should pass EC operation regions to acpiec(4)
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    port-i386-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Jul 24 09:30:01 +0000 2010
>Originator:     Jukka Ruohonen
>Release:        current
>Organization:
-
>Environment:
>Description:

The so-called WMI may contain EC's operation regions. These need to be
passed to acpiec(4) to ensure that we do not open a can of worms.
This may also cure some of the infamous ACPICA error messages such as:

        ACPI Error (evregion-0666): No handler for Region [FOOBAR]
        (ffffff0000000000) [EmbeddedControl] [20070126]

>How-To-Repeat:

Code and DSDT exploration.

>Fix:

The acpiwmi(4) driver should install EC address space handler and pass
everything to acpiec(4) by using acpiec_bus_read() and acpiec_bus_write().

Note that this is already done in the equivalent FreeBSD driver.