On Wed, 12 Jun 2013, victor yeo wrote: > I did another usbmon capture from the moment usb cable is plugged into > the Ubuntu x100e laptop. This time the usbmon does not have -75 error. > When the SCSI_READ_10 command request for 4096 bytes of data, and the > data is returned by the gadget, usbmon simply shows -108 error. The > gadget driver log and usbmon trace are attached. Again, the -108 indicates that the host controller disabled the port. The usbmon trace confirms this. I think the most common reason for disabling a port in this way is that the device tried to transmit a packet across a microframe boundary. > The FIFO size in gadget bulk out endpoint 1 is 512 bytes, so i break > the 4096 bytes of data into 8 chunks of 512 bytes, before returning > them to Ubuntu. I guess it would not be the root cause, won't it? It's hard to say without looking at the signals on the wire. Are you certain the hardware really is sending 512 bytes for each chunk? That's why you need to use a bus analyzer -- to see what's actually going on. 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
