Walker, 28, made his name at Bramall Lane and remains a die-hard fan.
And he revealed: “I started there so I'd like to finish there.
“I don't know if they would want me or not — but we will see.
“Even if I just do a year there and hopefully pass on my knowledge of football to the youngsters coming through.
“I'm 29 at the end of this month but still feel fit. I played my 400th league game a few weeks ago, so I've racked up the numbers.
“Touch wood, I can play for many more years."