http://visarts.ucsd.edu/icam-interdisciplinary-computing-and-arts-major indicates that the ICAM major is not that heavy in CS courses, though he could try to take additional CS courses as out-of-major electives. However, getting into CS courses as a non-major is likely to be difficult at UCSD, due to the extreme impaction of the CS major (in recent quarters, changing into CS required 4.0 or 3.9 GPA).