I teach in an ASD unit and these are some common accommodations my student have through high school. I don't know what is allowable/customary in college or what might benefit your son. I'll just list them and you can decide what might help him
- 1 additional day for classwork/homework for every day alloted
- as much time as is needed to finish any started portion of a test in a given school day
- preferential seating
- small group for testing and reduced stimuli in testing area
- increased opportunity for movement
- frequent breaks
- reduced amount of classwork/homework required for student to show mastery of skills
- directions repeated, clarified, in writing (as needed by student)