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Controlling the camera is done via writing “registers” - think of them as address locations. There are generally 4 ways to interface with the camera from a host:

1. standard UVC - this one is automagically supported by any UVC 1.1 compliant OS, which in the year 2017 would be “any modern OS”. This interface covers the universally standardized controls for USB Video Class
2. direct I²C access via Cypress's FX3 interface, using control port 0x20. This allows access to all sensor's registers (at your own risk!). For more information search the web for documentation on the sensor in your camera (as of October 2017 that would be OmniVision 10823 sensor)
3. FX3 Host Vendor Command Interface - this interfaces with the Cypress's FX3
4. FPGA I²C Access - a “window” into a host of additional commands that are performed on FPGA and (sometimes) are just a pass-through to the sensor's I²C

The last two (FX3 HVCI and FPGAI²C) are described in FX3 HVCI and FPGA I²C commands.