Maybe the best solution would be for 824[15] to not claim compatibility
with 8250 at all then.

Or at least it should have a more specific entry for this
"special" 16x50 UART, and that one should be probed first.

If the device tree contains an entry that matches
what the generic driver looks for, it better be something that can
be handled by that driver.

Pretty much; you can't make this rule too strict though,
if a device mostly works with the generic driver, you can
claim compatibility with it -- keep in mind that that can
come back to bite you though, like in this case.  The
advantages do outweigh the disadvantages sometimes, it's
all a tradeoff; avoid it if possible.


Segher