Re: loading firmware while usermodehelper disabled.

That said, I guess there are more complicated / difficult pieces of
hardware that might not do that. Is that the case here? Can we detect
that the firmware needs reloading and have the primary driver "yield" to
the firmware driver?

That doesn't really make any sense in the way USB works.

However if you've got a system to load and pin firmware *on suspend* and
flush it post resume then you don't actually need special 'firmware'
drivers just a slightly fancier lib/firmware that refcounts and handles
load on suspend/delayed flush.

(and probably a sysctl for cache tuning so that typical small firmwares
get cached on bigger boxes anyway for speed)