What does X need PM for anyway?

[kim at klassmaster.com]

Hi,

there has been this checkin to CVS which has kind of puzzled me:

<URI:http://cvs.freedesktop.org/xorg/xc/ChangeLog?rev=1.1226&view=markup>

The question I'm wondering about is, what is any X driver supposed to do
with these events? I hear that this only includes power management
related events. Does X need to save state, does it restart parts of
itself, or does it need to block a suspend process if it can't cope with
it?

Furthermore, which drivers actually handle ACPI events? I haven't been
unable to get a definite answer on #xorg, that's why I'm asking here.

TIA,
Kim Krecht