> > I have a bunch of USB devices configured for ethernet over USB > > connected to my machine. The host is running a 2.6.16 based kernel and > > I notice that rx errors reported via /proc/net/dev keep increasing > > infinitely. Initially the device responds without any problems, but at > > some random time, eventually the device and USB subsystem seem to lock > > up, i.e. commands like lsusb begin to fail. > > > > After some debug statements, I see that the RX errors are due to -71 > > EPROTO errors. Any help appreciated in understanding what is happening > > here. Here are the related messages (the messages keep repeating): > > > > ohci_hcd 0000:00:04.0: urb c7881c60 path 2 ep1in 6d160000 cc 6 --> status > > -71 > > ohci_hcd 0000:00:04.0: urb c3a33ce0 path 2 ep1in 6d160000 cc 6 --> status > > -71 > > ohci_hcd 0000:00:04.0: urb c3a33e00 path 1 ep1in 6d160000 cc 6 --> status > > -71 > > ohci_hcd 0000:00:04.0: urb c7881cc0 path 2 ep1in 6d160000 cc 6 --> status > > -71 > > These error codes indicate low-level USB communication problems. > There may be something wrong with the USB cable, or the device's USB > interface may have stopped running.
We checked the USB cable and protocol on the wire and everything looks good. The USB device that is connected to the hosts looks fine well. Finally we see this in the NXP ISP1563_Errata_070417: "Afer receiving a continous series of NAKs, ranging from 150 ms to 500 ms, the ISP1563 will retun a condition code 06h (PID failure) in the general Transfer Descriptor (TD). This error causes the software to stall the endpoint" "The workaround is to provide a software patch. The HCD can be modified so that whenever a PID check failure occurs, the HCD will not inform the client driver. Instead it just resubmits the TD on its own and the transaction continues". Is there exisiting code that demonstrates how to resubmit a TD? The suggested workaround does not seem good design. Any ideas? Thanks. ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
