Chile, sixth in the South American group and outside the qualifying berths, are away to Peru on March 22 and at home against Uruguay four days later.
Valdivia, who plays for relegated Palmeiras in Brazil, was one of five players sanctioned by former Chile coach Claudio Borghi after returning late and drunk from a day off during preparation for earlier qualifiers.
He is the last of the five to return to the fold, earning his recall from new coach Jorge Sampaoli, who will take charge in a qualifier for the first time having replaced fellow Argentine Borghi in December.
Valdivia could walk right back into the starting line-up since fellow midfielder Matias Fernandez, also picked, has seen little action with Fiorentina this season and picked up a right leg injury in January.
Juventus midfielder Arturo Vidal was not picked as he will be serving the remainder of a three-match suspension after being sent off in a 3-1 defeat away to Ecuador in October.
Chile have slipped down the standings after three successive defeats. They have 12 points from nine matches, eight points behind leaders Argentina.
The teams finishing in the top four places in the nine-nation group will go through to the finals in Brazil next year. The fifth-placed team will go into a play-off with an Asian country for one more berth.