What notebook do you have?
The mic jack records the audio signal. But I assume you want to use the mic jack an line-in. Right?
Usually you have to set the default device in recording tab.
In control panel -> sound -> recording tab.
If you will not see any further devices but only mic jack then you should click right and should enable the options; show hidden devices and show disabled devices.
Possibly then you could enable line in.
Otherwise such option is not available and not possible