[yocto] how to handle a source tree with both user-space and kernel module sources

[Hans Beckérus]

How could a package that is part of one single git repo but contains
both user-space libraries and several kernel modules be built?
Is there some existing "best praxis" that could be applied?
Currently what we have done is to split this into two recipes, one
that inherits from autotools and the other that inherit from module.
This works fine, but... The problem now is that there will be two
copies of the source repo, one in each package. Is there some way that
a recipe can
inherit from both autotools and module and thus use two different S
targets? Or is our current approach the only way to easily do this,
and thus having two copies
of the repo is just a side-effect that we simply need to accept?
Splitting the source repo is almost out of the questions since they
are heavily dependent on shared header files etc.

Hans