That's likely true - my machine works similarly, it doesn't list any
keyboard or mouse controller in PnP and Windows doesn't see them if no
device is plugged in at boot. The PnP devices for them are still
defined, but they are marked as disabled (the _STA method in the DSDT
returns 0). So we could likely detect that case and say "hey, the device
is there, just turned off, maybe we should try and see if it works
anyway". Whereas if the device is not there at all, we'd likely be
better off leaving it alone, by default anyway.
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