A camshaft phaser, including: a stator including radially inwardly extending protrusions with radially outermost ends; a rotor including radially outwardly extending protrusions radially outermost ends; chambers at least partially bounded by a inwardly extending protrusion and an outwardly extending protrusion; first seals disposed in the radially innermost ends and facing the rotor; second seals disposed in the radially outermost ends and facing the stator; first and second wedge plates radially disposed between the rotor and the stator; and a displacement assembly arranged to for an advance mode, displace the first wedge plate to enable rotation of the rotor, with respect to the stator, in the first circumferential direction and for a retard mode, displace the second wedge plate to enable rotation of the rotor, with respect to the stator, in a second circumferential direction opposite the first circumferential direction.