The Chargers signed Geno smith to compete against Cardale for the backup QB spot.  

Head Coach Lynn still has a very favorable view of Cardale. But they are searching for the future. 

I think CJ will be the guy in SD if their coach keeps his job.

http://www.espn.com/blog/los-angeles-chargers/post/_/id/23873/chargers-challenge-cardale-jones-add-competition-to-qb-room-with-geno-smith-signing