On Thu, 18 Nov 2010, Tatyana Brokhman wrote: > USB 3.0 hub includes 2 hubs - HS and SS ones. > Thus, when dummy_hcd enabled it will register 2 root hubs (SS and HS). Hmm. A quick comparison with the original source shows that you neglected to add code for SuperSpeed transfers to periodic_bytes() and show_urb(). > @@ -1352,6 +1544,9 @@ static void dummy_timer (unsigned long _dum) > case USB_SPEED_HIGH: > total = 512/*bytes*/ * 13/*packets*/ * 8/*uframes*/; > break; > + case USB_SPEED_SUPER: > + total = 400 << 20; /* 400MB = 400*(2^20) bytes */ > + break; Somehow I doubt that SuperSpeed USB, quick though it is, can transfer 400 MB in one millisecond. Where did you get that number from? I can't find the appropriate table in the USB-3.0 spec (it might not be there at all), but with a bus transfer rate of 500 million bytes/s it seems clear that you can't transfer more than 500000 bytes per frame. The actual limit must be lower than that, maybe something like 1024 bytes/packet * 60 packets/uframe * 8 uframes/frame = 491520 bytes/frame. Alan Stern -- 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
