No, not "AFAIK" ... since when I told you explicitly that was untrue,
you then ignored that statement. And didn't look at the specs that
I pointed you towards, which provide the details. (USB 2.0 spec re
hubs; and of course the Linux-USB hub driver ... www.usb.org)
The events that a hub receives say pretty exactly what happened.
You should know that already, since USB behaves that way even
when the system is _not_ suspended ...
The full mechanism for USB is more like wakeup signaling on USB triggering
hub wakeup (possibly cascading through a few layers of external hub), at
some point triggering root hub wakeup, which maps to a PME# signal. That
relies on no more than VBUS being powered at a fraction of a milliAmpere,
and the equivalent of a pair of voltage comparators triggering wakeup when
USB signaling changes from J to K states for something like 10 msec.
Did you read about the PME# signal in the PCI PM spec? www.pci-sig.com
Maybe you could try that.
Also the ACPI spec ... the early chapters give a decent overview of the
different components of that model. (ISTR two chapters try that, with
the second being more to-the-point despite some duplicated graphics.)
- Dave