B777 Captain reported a failure of the flaps to retract after takeoff. After consulting maintenance; the crew used an alternate flap extension procedure and returned to the departure airport for maintenance.

Narrative

Flaps/Slat Control ICAS (Indication Crew Alerting System) with intermittent flaps drive ICAS. Flaps Failed to retract from takeoff flap setting of flaps 5. Decelerated the plane back to a reasonable speed; contacted departure for vectors of the departure. Entered holding to run checklists; attempted to extract flaps using alternate flap switch to no avail. Conferenced in dispatcher/maintenance; determined the flaps drive was a computer anomaly; as it was no longer present. Determined the asymmetry was not a likely cause; we extended flaps to 20 using the flap alternate extension. Coordinated with ATC for a return to ZZZ for an ILS using CAT2 auto land procedures. Wx was low IFR barely CAT 1 with 60M ceilings. Landed uneventfully with Crash Fire Rescue standing by. We had plenty of fuel for an air turn back to ZZZ so we had time to coordinate and troubleshoot prior to landing. Aircraft was previously written up for a flap drive malfunction. The problem migrated from flap drive to flap/slat control after fix. Could be a faulty flap computer making repair difficult. Consolation with Boeing may be required to fix the actual problem or problems.