这个是rda升级版的驱动, rda.c rda.h

RDA5802 datasheet SINGLE-CHIP BROADCAST FM RADIO TUNER Rev.3.0–Sep.2008

The RDA5802E (RDA5802 Enhanced) is a single-chip broadcast FM stereo radio tuner with fully integrated synthesizer, IF selectivity and MPX decoder. The tuner uses the CMOS process, support multi-interface and require the least external component. Th

rda5802的驱动，可以选择上升下降频率