Is it a foul?

[fisherj]

A1 drives to the basket and picks up the dribble, looses control of the ball prior to impacting and dislodging legally positioned B1, all contact on B1 was ball and A1 did not have either hand on the ball. The ball transfered the impact between the bodies of the players. Had A1 been in control it is a charge all the way. What do I have.