There are two similar phrases with different meanings. -1- to be used to something (= to be accustomed to something) Are you used to cold weather? Yes. I live in Canada, so I am used to -25C temperatures in the winters, but I am not used to hot weather like 45C in North Africa. -2- used to do (= a former habit or a former state) Did you use to spend time with your grandparents? Yes. When I was a child, I used to spend my summers with my grandparents. (But, I don't do this anymore.)

Did you use to get up early? And 'did you get up early previously ?' Are slightly different. The first sentence implies that it was something you did regularly in the past but no longer do. eg. I used to swim every day when I lived by the beach. I used to cycle to work when I had a bike. The second sentence only really applies to something you did on one occasion, the action was not continual, it was not a habit.

"Used to" is not an adjective, it's a verb and it's by default in Past Indefinite thus if you make a question it follows the rules of Past Indefinite. Also mind the differences in meaning between "be/get used to doing smth" and "used to do smth" which Chris pointed out. They are totally different.