Larsson started his career at Arsenal at the age of 16
Sunderland have confirmed the signings of Birmingham winger Sebastian Larsson and Coventry keeper Keiren Westwood.
The pair are both out of contract with their current club and will officially join Steve Bruce's side on 1 July.
Larsson, 26, has been with Birmingham since 2006 but was
released by the club in May
following their relegation from the Premier League.
Coventry had hoped to keep 26-year-old Westwood, but the Irishman rejected the club's offer of a new deal.
Sky Blues boss Andy Thorn said: "We obviously have no say on where Keiren goes but he's gone about everything the right way.
"It is nice to have some clarity on the situation and now we can move on."
Westwood's fellow Republic of Ireland international, Joe Murphy, who was released by Scunthorpe at the end of last season, is thought to be favourite to fill the gap at the Ricoh Arena left by Westwood's exit.
Larsson was close to a
move to Sunderland's rivals Newcastle in January
and could replace Jordan Henderson in midfield after the England international joined
Liverpool earlier this month
He won the Carling Cup with Birmingham last year but could not prevent their relegation to the Championship.
Bruce is also in the market for
Ipswich's England Under-21 striker Connor Wickham
and are in negotiations with Chunnam Dragons to sign 20-year-old South Korea international forward Ji Dong-won.