It's about the ldisc number. Both bluetooth and cg2900 register themselves
to ldisc 15 (N_HCI). A user doing TIOCSETD can only get one of the two.
The solution would not be to make the two ldisc implementations mutually
exclusive, but to make cg2900 use a new ldisc number, e.g. N_HCI_CG2900.
However, I'm still not convinced that this is actually necessary, we might
be able to add hooks into the existing N_HCI implementation for the
extensions in cg2900.
Arnd
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