The adjective form of "camp" is "camp", not "campy". It is not derived from the noun "camp" or at least not in the usual way. In fact, there isn't really a noun form of the word unless you mean a bunch of tents. "Nounized" forms of the word occur only very rarely, usually to allow speakers more readily to define or comment on the phenomenon. As "camp" is undefinable, this is a pointless activity that should be discouraged. Use the correct adjective and forget you've ever heard the noun used.
(Triggered by use of the wrong adjective form on the blog under Dominic Deegan, but could have been triggered by a million other occurrences.)
