Laura Love
Black, Native American, and white. She's been described as "afro-celtic" (which just looks to me like the refuse to refer to someone who looks like her as simply "celtic") or bluegrass. She doesn't get the credit she deserves. "Bang Bang" is one of my favorite songs by her.

Labi Siffre
No doubt his most recognizable song would be "I Got The..." because the second half was sampled by Dr. Dre for Slim Shady, but he's mostly a folk artist. His other most recognizable songs might be "It Must Be Love" and "Loving Laughing Crying Lying" due to the covers. Imo he's one of he most brilliant singer songwriters the industry has ever seen and would be a bonafied legend if he were white... and straight.

Cree Summer
She only made one album (Street Fairie) but it was very much soft rock, and I loved it.

Kenna
You probably know of him. Really outside the box, musically and found some success with Neptune production. His whole songwriting approach is very much alternative rock.

Lenny Kravitz
No explanation needed there

The Family Stand
Their first album "Moon In Scorpio" had more rock on it, but even on the more R&B leaning "Connected" they had joints like "What Must I Do Now" and "Don't Ask Why."

On that note, here are more who were either genre benders with many rock songs or albums in their catalogs or classified as something other than rock simply due to them being black.


Prince

Ike & Tina Turner (recorded "Drift Away" in the middle of an album and it didn't sound out of place at all)

Shuggie Otis (the original Strawberry Letter 23 could be this post's theme song)

Terence Trent D'arby aka Sananda Maitreya

India.Arie

Me'Shell Ndegeocello (an album like "Weather" for instance)

Van Hunt

Gnarls Barkley

N.E.R.D.