[ltp] Re: ibm-acpi-0.2

[Borislav Deianov]

Hi Andr,

On Sat, 14 Aug 2004 22:57:04 +0000 (UTC) André Wyrwa <a.wyrwa@gmx.de> wrote:
>
> How does this integrate with the existing ACPI framework (i mean the
> general kernel acpi driver, proc and sysfs interfaces and acpid)?

It uses the existing ACPI framework to generate more ACPI events and
allow control of ThinkPad specific devices. In particular, it creates
several files under /proc/acpi/ibm that show status and allow control
of various features. Events are generated through /proc/acpi/event and
can be handled via acpid.

> I always thought that the way to get the Fn combinations for ACPI
> work properly would be to somehow trigger them (i.e. via tpb) and
> write the according strings to /sysfs/power/state or
> /proc/acpi/sleep?

Depending on the firmware, some events may need to be explicitly
enabled. Such is the case with Fn-Fx combinations on ThinkPads. The
standard ACPI drivers don't do this because the methods are
IBM-specific.

TPB is not using ACPI. For whatever reason, some Fn combinations
(e.g. for LCD brightness and sound volume) do not generate ACPI events
but show up in /dev/nvram instead. TPB monitors /dev/nvram and acts
accordingly. I use both TPB and ibm-acpi to get full control of the Fn
key combinations.

> Are there plans to integrate this with tpb somehow? Does this make
> sense? (To me it would, because having the key triggering in
> userspace enables one to choose the way the user feedback is done.)
> Or am i getting something completely wrong here?

Unfortunately, the mechanisms involved seem completely separate, so I
don't see a good way to integrate them.

> > 	- limited docking and undocking
>
> This is great, but raises a similar question...is this going to be
> the thing that triggers hotplug or does it not need hotplug at all?
> Because also i thought that docking/undocking in generell was
> planned to be done via hotplug?

I'm not quite sure yet. The ACPI framework has no explicit hotplug
support yet. IDE hotplug is not yet supported in 2.6 but I'm told it's
on the way. So far, ibm-acpi allows me to plug and unplug my X40 into
the X4 dock without the scary BEEP-BEEP-BEEP, and after docking the CD
drive in the dock works (with some issues, e.g. no DMA). Basically,
this feature is very experimental.

Wishes,
Boris