The 24-year-old has only featured once so far this season, in the Capital One Cup, having seemingly fallen behind the likes of Joey Barton, Gary O'Neil, Alejandro Faurlin and Karl Henry in the midfield pecking order.
Redknapp has promised he will "get his opportunity", though, after seeing him word hard in training.
The QPR manager said: "He's here training but hasn't got into the side.
"He'll get his opportunity I'm sure. He has been working hard and has shown a good attitude this year, so it's up to him."
Stoke, now managed by former Rs boss Mark Hughes, were linked with Diakite in the summer, but a move failed to materialise.
Redknapp will not stand in the player's way if he decides to leave Loftus Road in January - but admits a loan exit would not be his preferred option.
"It depends if someone wants to take him," said Redknapp, who has steered QPR into second place in the Sky Bet Championship.
"I'm not mad about loaning him out because we need a squad here. He could be important to us still."