Brandon Burnett

iMX35 USB Gadget Reliability Issue

Discussion created by Brandon Burnett on Feb 22, 2012

Hi all,

 

My team has enabled the USB Gadget driver on Linux iMX35 board. The board appears as a peripheral on our Linux dev machine and we are able to communicate with it fine over serial using /dev/ttyACM0.

 

The issue we seem to be having is that the USB Gadget driver seems to stop accepting our data after certain intervals. We've noticed that it seems to happen when we send a lot of data over /dev/ttyACM0 quickly.

 

We've written a small C application (you'll find it attached) that simply opens /dev/ttyGS0 on our iMX35 board and writes whatever it receives back (an echo application, in essence). On our dev machine, we have a python application that simply writes data to /dev/ttyACM0 and checks that it receives the same information back. Depending on how quickly we're sending data, it'll typically last anywhere between 2-10 minutes before the gadget driver stops responding. Obviously, we need it to last indefinitely.

 

I was wondering if anyone else had encountered similar issues and if they were able to find a patch/workaround that increased the reliability of the USB Gadget driver.

 

Thanks!

-Brandon

Original Attachment has been moved to: 318-echo.py

Original Attachment has been moved to: 317-echo.c

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