43.5.1 I/O Lines
The parallel interface pins used for interfacing the ISC are multiplexed with the PIO lines. The programmer must first program the PIO controller to assign the ISC pins to their peripheral function. If I/O lines of the ISC are not used by the application, they can be used for other purposes by the PIO controller.
When the MIPI link is used to interface the ISC, refer to the section "Camera Serial Interface (CSI)" to enable the MIPI inputs (not multiplexed with PIO lines).