Cyclists often have outer quad (and hip flexor) strength that dominates a relatively weaker inner quad. Apart from icing, ibuprofen, trigger point therapy to work out knots in outer quad, patients with patellar tendinitis need to strengthen their VMO muscles to avoid these kind of injuries.

Full range of motion squats (with good form) are excellent to build up to. Try googling "Peterson Step-ups" to strengthen VMO. Also, if you have access to a weight sled or heavy tire, pull/drag it backwards. These build up the VMO muscle (tear-drop shaped that connects to inner knee patella).

Good luck.