libpayload: Bring USB hub driver to a working state

This adds proper device attachment and detachment detection and port enable-
ment to the USB hub driver. Support for split transactions is still missing,
so this works only with USB2.0 devices on hubs in USB2.0 mode and USB1.1
devices on hubs in USB1.1 mode.

Change-Id: I80bf03f3117116a60382b87a4f84366370649915
Signed-off-by: Nico Huber <nico.huber@secunet.com>
Reviewed-on: http://review.coreboot.org/1080
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
1 file changed