Here are the data structures with brief descriptions:

_Freq_Info_Type
_R828_I2C_LEN_TYPE
_R828_I2C_TYPE
_R828_RF_Gain_Info
_R828_SectType
_R828_Set_Info
_Sys_Info_Type
_SysFreq_Info_Type
cmd
cmd_state
command
dongle_info_t
e4k_pll_params
e4k_state
fm_state
gain_comb
llist
option
pll_settings
reg_field
reg_field_ops
rtlsdr_config
rtlsdr_dev
rtlsdr_dongle
rtlsdr_tuner_iface
strbuf