Prevent attach of modem serial emulated device on USB attach?

[Karl Denninger]

So I have managed to get access via ugen to one of the USB devices I
want to talk to.

I would like to generalize that in a library, but am confounded by a
/second /device that comes up "looking like a modem", although it is
not.  This is convenient if you want to open and deal with it like a
modem, but unfortunately that attachment appears to prevent me from
successfully using it with the ugen interface at the same time, as the
attachment looks like it "eats" the inbound byte stream.

Is there a reasonably-easy way to /prevent /FreeBSD from declaring this
device eligible to be attached as if it was a character-style modem,
leaving it only on ugen?  I have figured out how to use devd to change
permissions on attach, but not how to prevent it from attaching a
generic USB device to a specific driver.

-- 
Karl Denninger
karl at denninger.net <mailto:karl at denninger.net>
/The Market Ticker/
/[S/MIME encrypted email preferred]/
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