Regression 2.6.31: xc5000 no longer works with Myth-0.21-fixes branch

[Mark Lord <lkml@rtr.ca>]

Devin,

Thanks for your good efforts and updates on the xc5000 driver.
But the version in 2.6.31 no longer works with mythfrontend
from the 0.21-fixes branch of MythTV.

The mythbackend (recording) program tunes/records fine with it,
but any attempt to watch "Live TV" via mythfrontend just locks
up the UI for 30 seconds or so, and then it reverts to the menus.

I find that rather odd, as mythfrontend normally has very little
interaction with the tuner devices.  But it does try to read the
signal strength and quality from the tuner, so perhaps this is a
clue as to what has gone wrong?

I also took just the xc5000.[ch] files from 2.6.31 and tried them
with 2.6.30, to help isolate things.  Exactly the same behaviour
was observed there, too.  The mythbackend could tune/record,
but the mythfrontend would lock up.

???