On Tue, Jul 20, 2021 at 01:04:38PM +0000, David Laight wrote:

> Having said that, you might want a loop in the driver so that
> application requests for longer transfers are implemented
> with multiple hardware requests.

No, that's something that should be and indeed is done in the core -
this isn't the only hardware out there with some kind of restriction on
length.

> I do also wonder why there is support in the main kernel sources
> for hardware that doesn't actually exist.

We encourage vendors to get support for their devices upstream prior to
hardware availability so that users are able to run upstream when they
get access to hardware, this means users aren't forced to run out of
tree code needlessly and greatly eases deployment.