Johnson began playing guitar when he was 15, honing his chops in local rock bands such as Treacherous Funk, Pilot, and Dealer, throughout his teens and early twenties.

On The Time's third album, Ice Cream Castle, Johnson contributed to the hit singles "The Bird" and "Jungle Love", which were helped by the popularity of the Purple Rain film.

Throughout the late 1980s and early 1990s, Johnson also featured on the soundtracks to the Breakfast Club (contributing "Heart Too Hot to Hold", a duet with Stephanie Spruill), Pretty in Pink, Another 48 Hrs.

Johnson has produced a wide variety of artists, most notably Janet Jackson, Paula Abdul, TaMara and the Seen, After 7, Da Krash, Kool Skool, Debbie Allen, Cheryl Lynn, and Les Rita Mitsouko.

Other members of the house band included Booker T. Jones, Bobby Ross Avila, Narada Michael Walden, Ernie Fields, Jr., Freddie Hendrix and Fred Wesley.

King, Buddy Guy, Mick Jagger, Jeff Beck, Warren Haynes, Derek Trucks, Susan Tedeschi, Keb Mo, Trombone Shorty and Gary Clark, Jr.