Johnson, who was on a two-way deal with the Heat, is getting upgraded to a a standard two-year contract, ESPN's Shams Charania reports.
Johnson provided two rebounds in six minutes during Wednesday's 134-93 win over the Lakers.
Miami coach Erik Spoelstra said Monday that Johnson (ankle) will be ready for training camp this week, Anthony Chiang of the Miami Herald reports.
Johnson (ankle) won't play in Monday's Summer League Championship Game against the Grizzlies, Ira Winderman of the South Florida Sun Sentinel reports.
Johnson (sprained ankle) won't play in Sunday's Summer League game against the Warriors, Anthony Chiang of the Miami Herald reports.