How do I allow a coupon code to be used multiple times for the same item in 1 single purchase?

I have a $2 discount coupon on product A.

If customer buys Product A, he gets $2. If he buys 2 Product A in 1 order, he gets $2 off too.. How do I make it such that he gets $4 off?

Sorry, Percentage discount is not feasible for this.




During checkout, when customer clicks the coupon code, he can see an explanation to the coupon. How do I hide this section of the text shows the restrictions? I tried editing popup_coupon_help.php but it still shows the products in the restriction.