What is the the role of atp and nadph in the calvin cycle?

ATP acts as a source of chemical energy whereas NADPH acts as a reducing agent.

ATP provides energy for the regeneration of RuBP, and then it goes back to being ADP. ATP also provides energy which is used during the reduction of GP (see point below). NADPH provides a hydrogen ion for the reduction of GP into GALP.

Note: - ribulose-1,5-bisphosphate is RuBP - 3-phospho-glycerate is GP - glyceraldehyde-3-phosphate is GALP