Power-Mgt

[M. Warner Losh]

In message: <20080318085804.I50685 at maildrop.int.zabbadoz.net>
            "Bjoern A. Zeeb" <bzeeb-lists at lists.zabbadoz.net> writes:
: what actually happens to an unrecognized card or a card with no driver
: loaded currently? How much power does an unsued card use and can we do
: anything about that? Are we perhaps already doing something about
: that?

For PCI it is set into D3 state.  Or at least was until this caused a
problem with some raid controllers that didn't follow the rules and
had extra devices that the card used, but that the OS didn't have a
driver for.

For PC Card, the card is powered down entirely.  For CardBus I think
the same.  For USB, ugen takes it, and therefore it is powered up.

Warner