nvcamera.conf for USB Webcams on Android 5/6

I am working on the jetson platform running android and I have a question regurding the nvcamera.conf. When it says use “usb” to search for usb device where do we put this in the conf?

This is my configuration:

# format, cameraName=device,direction,orientation,type
# type can be 'stereo' for stereo capable, 'mono' for not stereo capable,
# 'usb' to enable searching for a usb device and where to put it in the list
#  if found.  Lines must be shorter then 256 characters
version=1
camera0=/dev/video0,front,270,mono   // front external usb camera
camera1=/dev/video1,back,270,mono   // back external usb camera
camera2=/dev/video2,front,270,mono   //  2nd front external usb camera

So should I change the type to usb?

# format, cameraName=device,direction,orientation,type
# type can be 'stereo' for stereo capable, 'mono' for not stereo capable,
# 'usb' to enable searching for a usb device and where to put it in the list
#  if found.  Lines must be shorter then 256 characters
version=1
camera0=/dev/video0,front,270,usb   // front external usb camera
camera1=/dev/video1,back,270,usb   // back external usb camera
camera2=/dev/video2,front,270,usb   //  2nd front external usb camera