USB camera on Hikey 620

Hi,
I have bring up Android Pie on Hikey 620. I have interfaced USB camera with the Hikey board. But when I use OpenCamera application to capture image/videos I’m getting following error:
FAILED TO OPEN CAMERA
CAMERA MAY BE IN USE
BY ANOTHER APPLICATION?
Please give suggestion.

could you please attach debug logs (logcat, dmesg).