The original question here, as I interpreted it, was about interest earned *within* the HSA, not new deposits of money from any source outside the HSA. If you deposit cash in your HSA, regardless of the source of that case (other than a rollover of a distribution from an HSA), that deposit *is* a contribution and counts toward your contribution limit. Contributions include deposits made from payroll deductions under a cafeteria plan provided by your employer or deposits made on your behalf by anyone.
