Hi Sarah, Alan, I was trying to enumerate a FS device using dummy_hcd but unfortunately it didn't work. The enumeration failed because "parent hub has no TT". I searched the code and saw that the hub->tt.hub is set if bDeviceProtocol=1, when according to usb2_rh_dev_descriptor (defined in hcd.c) bDeviceProtocol=0, meaning, no TT. So I have 2 questions: 1. Was dummy_hcd ever tested with FS devices? 2. How this is working for a real HS root hub? I'm sorry for asking this, but I didn't find it in the code and we don't have any convenient tools for host debugging so it's not so trivial. Thanks, Tanya Brokhman --- Sent by an consultant of the Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html