8 Replies Latest reply on Oct 24, 2019 3:49 AM by KandlaguntaR_36

    CX3 UVC ubuntu 18.04 uvcvideo: Non-zero status (-71) in video completion handler




      I have a CYUSB3065 based design. The firmware is based on an example:




      All I did is changed the resolution in USB descriptors and replaced the functions related to the image sensor.


      For testing, I compiled a simple example of how to grab an image from the USB camera found at:


      Simple C++ program to capture a webcam frame in Linux · GitHub


      The trick is that every second time I receive 0 bytes from the CX3 and the following error is generated to the kernel log:


      uvcvideo: Non-zero status (-71) in video completion handler.


      I used Wireshark to monitor the USB traffic and noticed that the camera indeed reports the error. I have several development boards with the same sensor (including Tania dev. board) I use and all these boards behave the same: getting single frame fails every second time, resulting in -71 error code in the kernel log.


      I think the fw lib generates the error reply in CX3 somewhere "deep inside" as no callback functions are called. DMA starts running, but the host just closes the connection as the result of the error message. I attach the Wireshark log. I have the impression that host does everything right but CX3 just fails every second time. Any comments, suggestions?


      BR, Madis