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With the inclusion of "Coming Home" on the Billboard charts, we also get the production and songwriting credits for the song. It is always possible that this is not final.

When the song was released, Diddy revealed that it was produced by Alex Da Kid and Jay-Z and that the verses were done by Jay-Z. A version of the song with J. Cole appeared online and seemed to be a reference vocal for Diddy, but it was not used in the actual song.

According to the Billboard listing for the the song, which features Skylar Grey, it was produced by Alex Da Kid and written by Alex Da Kid, H. Brook, Jay-Z and J. Cole. After running some Google searches, it appears that H. Brook might be Skylar Grey. I've reached out to Alex Da Kid and Grey on Twitter to confirm.

Update: The subsequent Billboard charts changed the credit for H. Brook to S. Gray.