On Wed, Apr 11, 2012 at 11:24:11AM +0100, Alan Cox wrote:

> If that code gets pulled out of IIO dumped into drivers/adc and has a bit
> of a different API to the gpadc code then no problem, gpadc can follow it
> happily enough. IIO can use it from staging and IIO can migrate whenever.

> It does make sense to think hard about userspace APIs for IIO but for
> kernel APIs its really being too conservative - we break kernel APIs
> every release. They are not set into stone.

The way I keep thinking about this (which I'm sure I've suggested
before) is that we should be refactoring IIO such that the userspace ABI
is just another in-kernel consumer of the device driver bit of IIO and
that driver bit should be small enough to just use.  I think that winds
up being roughly equivalent to your suggestion but means that there's
just one place to put the drivers which seems like a win.