I find the issue, in the sample code should add isHandled to allow SetupCB function return CyTrue.
//add by michael 0912 start
status = CyU3PEventSet (&glCx3Event, CY_FX_UVC_VIDEO_CONTROL_REQUEST_EVENT,
if (status != CY_U3P_SUCCESS)
CyU3PDebugPrint (4, "Set CY_FX_UVC_VIDEO_CONTROL_REQUEST_EVENT Failed %x\r\n", status);
isHandled = CyTrue; // Add this line
//add by michael 0912 end
Happy to heard that you solve this problem by yourself.