The 12-year outside linebacker intends to sign a contract with the Ravens on Wednesday and then announce his retirement.
Johnson played nine years with Baltimore before signing with the San Diego Chargers as a free agent in March 2012.
The 33-year-old spent three years with the Chargers, playing in 41 games and making 37 starts.
Drafted in the fourth round of the 2003 draft by Baltimore, Johnson became a regular in the starting lineup in 2007, the first of five straight seasons in which he started every game.
He finishes with 25 1/2 sacks, three interceptions, 348 tackles and one touchdown.
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