It seems to me as if you're speaking about a hypothetical scenario where Rust needs something from the interface that isn't required by other languages. And you can't articulate what that might be because you can't think of an example of what that would look like. And also, in this scenario, Rust is the primary user of this driver interface.

But if that's the case, it's getting really close to "if things were different, they'd be different". If that's not the case, then I don't understand your case.

There's nothing wrong with the interface. Rust can use it just fine. It doesn't do anything C code wouldn't. They're not even asking for anything from what I can see. The person who maintains the DMA driver doesn't want Rust _using_ his interface, he's rejecting PRs where Rust code is interfacing with his driver.

The closest analogy I can think of is he wrote a book, but he doesn't want left-handed people to read it.

The API maintainer should only be concerned how the API is consumed in only that it is consumable and doesn't cause unintended side effects. And neither of those should be impacted by the language used to consume the API.

You didn't, but Christoph Hellwig did -- which is what started off this whole kerfuffle last week.