A data storage system can employ at least one data storage device having a supplemental processing bus that connects a first controller to a second controller with the supplemental bus being exposed to an exterior surface of a housing. The second controller may be positioned on a portable computing component connected to the supplemental bus while the portable computing component is positioned external to the housing. The computing capabilities of the portable computing component are identified with the first controller to allow a supplementation strategy to be generated with the first controller in response to connection of the portable computing component to the supplemental bus. The supplementation strategy can then be executed by assigning at least one processing task from the first controller to the second controller.