> But I don't see how you will make it work when the root hub itself is > not enabled for wakeup and a non-hub device plugged into one of the > root hub's ports is enabled. > > It seems like you would need a usb_hcd_wakeup_not_needed(hcd, port) > subroutine. We'd just put that in the Tegra platform driver, I guess. Iterate over all ports, call usb_wakeup_enabled_descendants() on the connected device (if any) and disable that port's PHY if it returns 0 or wasn't connected. Since usb_wakeup_enabled_descendants() also counts do_remote_wakeup from the device itself and is safe to call even on non-hubs, that should work for all cases.
