Salmon hit a three-run shot in the first inning to jump-start the Angels. His other home run came in the fifth.
Ramon Ortiz scattered six hits over six innings and recorded his 10th win against six losses this season.
Eric Chavez and Billy McMillion homered for the Athletics.
Oakland starter Aaron Harang (1-3) took the loss.
Notable deaths of 2014 [PHOTOS]
LeBron James reveals his new Nike shoes