Confirmation of 'no visa needed' for us tourist

My family, with a 6 year old child, are traveling from the US to Hong Kong for 6 days and to Shanghai for 4 days, the back to US.
I have read many of the posts, I think that I know the answer but I wanted to confirm. For the travel itinerary that I described abive, an entry permit is NOT needed.
Thank you for answering.
Lucas