If the State is trying to revoke his suspension and send him to prison or jail, he is entitled to a revocation hearing. He is entitled to see the test result. When on probation it is not necessary to find drugs. He could revoked without UA if he admits using drugs. He can ask or sanctions short of revocation in some states, or try to get into drug court. He can ask that less than his whole time be revoked. He needs a lawyer and I imagine if he cannot afford one, Tennessee will appoint a lawyer.