Bobby Caldwell, the soulful singer-songwriter behind the 1978 hit “What You Won’t Do for Love,” has died after a long illness. He was 71.

His wife, Mary Caldwell, announced the news on Bobby’s Twitter, writing, “Bobby passed away here at home. I held him tight in my arms as he left us. I am forever heartbroken. Thanks to all of you for your many prayers over the years. He had been “floxed,” it took his health over the last six years and two months. Rest with God, my Love.”

Floxing occurs in the body due to mitochondrial damage and oxidative stress caused by an adverse effect from a fluoroquinolone antibiotic.

Caldwell’s smooth jazz song “What You Won’t Do for Love” was released in September 1978, his debut single after signing a recording contract with Miami label TK Records. In order to compete for airtime with Smokey Robinson, Teddy Pendergrass and the many Black artists of the “quiet storm” radio format, TK initially attempted to conceal Caldwell’s racial identity. But the song’s popularity only grew once he started performing it live, eventually reaching No. 9 on the Billboard Hot 100 chart and No. 6 on the R&B chart. The self-titled album, which featured him only in silhouette, eventually went double platinum.

After TK went bankrupt in 1981, Caldwell continued recording albums under his own name, while writing songs for other artists at the suggestion of singer Boz Scaggs. “The Next Time I Fall,” which he co-wrote with Paul Gordon for a 1986 duet by Peter Cetera and Amy Grant for Cetera’s album “Solitude/Solitaire,” not only reached the top of the Hot 100 and Adult Contemporary charts but also received a Grammy nomination for best pop performance by a duo or group with vocals.

Caldwell’s music has since been sampled hundreds of times (according to Whosampled, “What You Won’t Do for Love” alone has been used or covered by everyone from Aaliyah to Tupac). Notorious B.I.G. used “My Flame,” also from “Bobby Caldwell,” for the 1997 song “Sky’s The Limit,” and his song “Open Your Eyes” from the 1980 album “Cat in the Hat” was later sampled by rapper Common for his 2000 single “The Light.” In 2019, Lil Nas X was issued a $25 million lawsuit for sampling Caldwell’s “Carry On” (from the 1982 album of the same name) for a song on his pre-fame mixtape “Nasarati.”

Though Caldwell did not ever again reach the heights of success he experienced with his debut album, he enjoyed a brief late career resurgence after collaborating with R&B producer Jack Splash, of the funk outfit Plantlife, on the album “Cool Uncle.” He sings on the record alongside retro-soul luminary Mayer Hawthorne on “Game Over,” and on “Destiny” retains the same soulfulness that made his early work stand out among an explosion of smooth jazz contemporaries.