Smith started last season and recorded 25 receptions for 402 yards, ranking third on the team in both categories. He was projected as a starter on Penn State's depth chart released after spring practice, although he missed much of the spring with a foot injury.
Lions247.com reported Smith's departure earlier this week.
It's unclear if Smith's exit is related to a charge for possession of a small amount of marijuana and drug paraphernalia. The charges stem from a March 14 incident where police searched Smith's apartment. Smith has applied for the Accelerated Rehabilitative Disposition program.