The patch lets HCDs report the root hub remote wakeup feature to usbcore
through config descriptors, and lets usbcore say whether or not remote
wakeup (of host from sleep, by devices) should be enabled.

Both OHCI and UHCI HCDs have some remote wakeup support already; I'm not
too sure how well it works.  Given (separate) patches, their root hubs
can start to act more like other hubs in this area too.  That'll make
it easier to start using USB suspend mode.