Days after having kidney surgery, "American Idol" winner Phillip Phillips [1] is out of the hospital and back in action.

The 21-year-old singer-songwriter underwent a nearly seven-hour operation last Wednesday to remove massive kidney stones that sidelined him during his otherwise victorious run on the latest season of "Idol."

Phillips Makes 'Idol' History as 'Home' Sells 278,000 Downloads [1]

He checked out on Sunday afternoon, his rep confirms to THR.

E! News [2] has posted a photo of Phillips signing autographs and quoted him as saying: "Looking forward to the future."

The Georgia native, who managed to beat Jessica Sanchez in the May 23 finale despite his illness, opted to postpone surgery until Idol's 11th season wrapped up; he secretly went under the knife a whopping eight times while on the show to treat a buildup of kidney stones. Caused by a congenital condition, the stones have rendered his right kidney largely ineffective, prompting him to temporarily rely on a stint and the need for an operation that would bring about a more permanent solution.

As previously reported, Phillips had scheduled the surgery only a month before the latest cast of the Fox series embark on a 45-date U.S. tour. A rep for Phillips said he's still a lock for the July 6 kick-off in Detroit.