Raspberry Pi multi-camera adapter is designed for connecting more than one MIPI camera to a single CSI camera port on the Raspberry Pi board. One adapter board can connect 4 cameras on a single Raspberry Pi board.
Please note that the Raspberry Pi multi-camera adapter board is a nascent product that may have some stability issues and limitations because of the cable’s signal integrity and RPi’s closed source video core libraries, so use it at your own risk.
The latest revision of the Arducam Multi Camera Adapter is V2.2. The V2.2 undergoes firmware updates, but the specs, documentation, and tutorials on the V2.1 will still apply to the V2.2.