The product information sheet for the chip in the N800 indicates that it uses an I2C interface for tuning and the like. It also exposes decoded RDS data via the same interface, which provides an out-of-band metadata channel for radio stations, in addition to traffic information, time updates, etc.

http://www.nxp.com/#/pip/cb=[type=pr...61UK_1][0]

edit: My mistake. It's only one specific model in the family that supports it. *sigh*