Randy,
The only reason the net stuff works, is because CONFIG_NET includes igmp.c,Thanks for the analysis and summary.
which can't be compiled as a module. That means ip_compute_csum() will get
pulled out of the lib.a file for igmp, and thus be present for the net modules
that use it too. If igmp could be turned off, made a module, or stopped using
ip_compute_csum(), then the users of ip_compute_csum() that do depend on
CONFIG_NET would have the same problem as bttv does.
(I'm still waiting for those lkml.org links to load... timed out)
It seems a shame to create a new ip checksum function in the bttv driver when
a perfectly good one already exists and will already be present in just about
every kernel out there. Honestly, how common is NET=n and VIDEO_BT848=m
outside of randconfig?
This might happen on embedded devices, like a set top box or a PVR,
using a bttv hardware.
so just adding "depends on NET" should be OK then?
Seems very weird to have bttv module dependent on NET, just because a
checksum calculus function is defined there.
One possible solution would be to move this function to another place
and having both NET, BTTV and other places selecting it.