ACPI wake up via USB

[avx]

I've been pretty p*ssed for a long time now, since my BIOS only allows me to wake up the pc via network or PS/2, but not via USB - as in keyboard/mouse.

Two days ago, I stumbled over `acpitool -[wW]` by accident and I was pretty surprised, that it actually works(pressing some key on the keyboard or moving the mouse/clicking).

Related to that, I've got some questions.

a) do you know why the BIOS limits this functionality to PS/2?
b) does this somehow change the sleep-state? (I'm using `echo -n mem > /sys/power/state`)
c) some boards/BIOSes allow to be woken up only by a special key(-sequence), i.e. 'space' or 'C-Esc'. I guess not, but would that also be possible in my situation?
d) I've got two mice, one connected to my keyboard, the other one wireless with the connector on a front USB. The keyboard and the wireless mouse can turn on the system, but the mouse connected to the keyboard can't, why?

Thanks.
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