Preston boss Ferguson confirms talks with Stoke defender Dickinson
Dickinson is also a target for Sheffield United.
"All I can say is that I have a very, very good left-back in Callum - a good captain," Ferguson told the club's official website. "But I am aware of his past injury record and I hope that's not going to be the case this season.
"With his age it is difficult to play that number of games so I've got to be looking to bring a left-back in.
"I've spoken to Carl and he wants to come, as simple as that - we're just trying to negotiate a deal."