What was found
PHL - FLT 188 - EN ROUTE PHL TO YUL, AFTER TAKEOFF, RECEIVED ECAM AVIONICS SMOKE WARNING. AS FLIGHT WAS RETURNING TO FIELD, A SMOKE ODOR WAS DETECTED IN THE FORWARD PART OF THE CABIN. FLIGHT RETURNED TO PHL WITHOUT FURTHER INCIDENT. MAINTENANCE REPLACED THE AVIONICS BLOWER FAN. OPERATIONALLY CHECKS OK.