I consider to connect the AD9364, placed on a custom made board with Raspberry Pi 4 in the following way:
1. Raspberry PI SPI interface will be used for communication with AD9364
2. Raspberry PI GPIO pins will be connected to the AD9364 GPIO pins. A HW conversion to/from 3.3V/1.8V voltage levels will be implemented in HW
Do you see any issue with such implementation?