Take a look at page 167 where they talk about emulating the VBUS signal... this may be more "clean" method of trying to get the controller into host mode? Also, when I read the document it is apparent that the OMAP USB pins are not designed to be connected directly to the USB port. It needs some tranceiver chip between. I'm not sure if there are any other limitations on that tranceiver chip that prevent the host mode from working? (I don't think so, but you never know...)