Who Is To Find Research Ideas in Computer Science Research: PhD Student or Adviser?
The goal of the Ph.D is that you become a researcher that can do research by himself (find topics, solutions, etc.). However, during the Ph.D., the supervisor should still give you some guidance. Now the question is how much guidance? The answer depends on the supervisor.  There are some professors that are very busy and thus do not give much guidance, and there are also some professors that will look at what you are doing more closely. I would not see it as a problem if a supervisor told his student to find the topics by himself. Actually, if your supervisor is giving you more autonomy, it may be good in the end as the goal is that you become an independent researcher. Also, it is normal that during the Ph.D. you have more freedom than when you were doing a master degree because you are on your path to become an independent researcher.