There is this[0], but even with re-creating this patch on the latest wine-staging tree, I was unable to get Rekordbox (6, don’t try 7) to communicate with the board. That said, I was also unable to interact with Mixxx with the board, and that wasn’t running through wine. As a sanity check, I verified that the board runs fine on Rekordbox 6 on Windows. I was able to read the midi inputs from the board just fine from other programs on Linux, so I’m honestly not sure where the issue lies.

[0]: https://erhan.es/blog/using-pioneer-controller-with-rekordbo...