This message was posted on behalf of Intel Corporation
Thank you for contacting us. If the webcam is connected to the Edison via the USB port, then you should be using the microswitch towards the USB port (host mode). You also mention you’re using Arduino sketches to start and run the webcam. As you said, Arduino sketches won’t upload in host mode. An easier approach to use the webcam is described here https://github.com/drejkim/edi-cam. In this link, the goal is to achieve video streaming and shows in detail how to install the packages needed and running an example. Even if this may not be the goal of your project, it’ll help you configure the Edison and get started with the use of the webcam.
Another very useful guide can be found here: http://www.instructables.com/id/Intel-Edison-IP-Webcam/?ALLSTEPS
Let us know if you found this useful.