The 31-year-old striker spent a fruitful loan spell at Ipswich Town for the first half of the season but has since returned to QPR, with his future still undecided
Campbell managed just 11 Premier League appearances in the 2011-12 season, with only two of them coming as starts, and a short-term move to the Tractor Boys beckoned at the beginning of this campaign. The striker took his opportunity well, scoring 10 goals in 17 league outings.
Mick McCarthy's side are believed to be one of the clubs interested in signing the 31-year-old on a permanent basis, but Redknapp was unsure whether he would be selling the forward or keeping hold of him as QPR attempt to escape the relegation zone.
Speaking to reporters, Redknapp said: "There's been nothing really [offers for players]. The only one I've had people ring me up about is DJ Campbell.
"There are about six or seven Championship clubs who want to sign him. I'm pleased he's back here now and we'll see what happens."