What documents do I need to travel from Turkey to Hongkong with a China passport?

No other documents are needed, just a passport.

According to China's transit regulations, China passport holders do not need a pass to stay in Hong Kong for more than seven days.

According to the regulations of the Hong Kong Immigration Department, mainland residents who return to the Mainland from overseas via Hong Kong can get a seven-day stay with their passports, without showing their plane/car/boat tickets for returning to the Mainland from Hong Kong. China passport holders do not need permission to transit through Hong Kong to and from another country or region, but they must meet the entry requirements, such as holding a valid entry certificate of the destination and confirming that they have booked an overseas continuation car/boat/air ticket.