As now new iPhones are shipping with a mini jack to lightning adapter and AFAIK lightning connector should be super-programable, is it possible to get audio input from a mini jack plugged into adapter? In other words if I take a radio, and I pug a male-male mini jack into a headphones port, can I record the audio on my iPhone?
Unfortunately this is not possible.
The adapter uses a DAC (digital to analog converter) to convert the digital audio signal coming from the iPhone to an electrical signal that can be passed to the headphones.
The DAC only works in one direction. For the other direction (record into the iPhone using a microphone) you'd need an ADC (analog to digital converter.
No, unless you use a special adapter, the audio from the radio will be send over the audio output channel of the 2.5mm headphone jack, not the input channel. This means that your radio does not function as a microphone/aux input and you can't record the audio from the radio.