Hi All According to USB On The Go and Embedded Host Automated Compliacne Plan, item 6.7.22 A-UUT “Device No Response” for connection timeout, the "Device not responding” error message should be displayed when a non-responsive device is attached. I know that the presentation of the message is the responsibility of the application (user space), but to do this is necesary an event from usb driver (I think it). Nowdays when a non responsive device is attached, "unable to enumerate USB device on port... " is logged a in dmesg, but not event is dispatched (by example in usb_uevent). Without an event application should poll the log (loading the system unnecessarily) searching new "not responsive devices". To comply with the standard usb driver should be modified? I'm probably confusing responsibilities of user and kernel space. I appreciate your opinion/answer. Thanks in advance Christian