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We have RPi3B+ with Raspbian Lite installed, 2.5A power supply. We need to connect a specific USB camera (LEPTON PureThermal 2) and display its image. The connection with the camera works, it gives the correct image but after a while it stops and no frames are received anymore. It sometimes stops after a few seconds, sometimes after a few minutes, the time seems to be random.

We tried the solution based on libuvc and it starts giving "Pipe error". Solution based on V4L2 starts returning EAGAIN infinitely from ioctl(VIDIOC_DQBUF).

/var/log/kern.log report the following errors in this situation:

kernel: [21418.056754] Transfer to device 15 endpoint 0x1 frame 1099 failed - FIQ timed out. Data may have been lost.

kernel: [21421.932856] Transfer to device 15 endpoint 0x1 frame 879 failed - FIQ timed out. Data may have been lost.

kernel: [21443.020767] Transfer to device 15 endpoint 0x1 frame 1487 failed - FIQ timed out. Data may have been lost.

kernel: [21447.019344] uvcvideo: Non-zero status (-32) in status completion handler.

It is interesting that simply closing the device descriptor, does not really close the connection to the camera. We need close, reopen (camera still does not work at this time), close, reopen and then the camera starts working again.

The camera works correctly everywhere, only the connection with Raspberry Pi seems to be problematic. We tried disconnecting all other devices (HDMI, keyboard, mouse) but problem still appears.

Is there any specific Raspberry/Raspbian settings we need to enable? Or some specific driver needs to be installed? Or any other solution to make the camera working?

EDIT: Tested another RPi device and the problem appears too.

It looks that this problem is somehow related to the RPi load. If I create simple V4L2 code which repeatly reads image from the camera and displays the center pixel value, it works correctly for an hour. If I stress the device a bit (e.g. browsing in Chromium), the USB pipe error appears soon or later. If a frame displaying is added, the USB pipe error appears soon or later.

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