>> Everything works fine if i blacklisted USBHID driver. It seems the >> problem is not in my CDC device's hardware or software because I >> tested the device on multiple machines before. > > If there's nothing wrong with the CDC device then why does it generate > all those error messages in the log? That is really my problem, conflicting with USBHID driver somehow. When USBHID driver is not attached, there are no transfer errors at all (no kernel log messages). Also, even when USBHID driver is attached and the CDC device is plugged into the ebox on another USB port and attached to EHCD, there are also no transfer errors. While developing the CDC device, i also used Beagle 480 USB protocol analyzer and diagnosed traffic. All transactions were clean. I am not convinced that the root cause is in the CDC device. >> I am suspecting USB OHCD host controller or internal USB device is >> causing usb port resets. >> I am not sure where the root cause is, and hope that someone would >> help me on this issue. > This might be easier to debug if you used a kernel that was more recent > than 2.6.21. I agree. We should always test new hardware and debug with most recent and stable kernel. I'll be working on this and report back soon! Thank you, Toan -- 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
