When not using none_prefix for matching the responses of AT+XSIMSTATE
call, it will consume all notifications. And this includes the initial
SIM state that the modem sends at that point. Without this notification
the SIM will never be marked as inserted.
Since the udev support allows to specify a line discipline number as
part of the modem configuration, use that one and report and error if
it has not been set.
The +XSIM notifies us about missing or removed SIM. Use that for telling
the core if a SIM card is present or not. Besides that all other states
are treated as when a SIM card got inserted.
This supports a simple static multiplexer that is activated with setting
the line discipline 23 on the TTY. It is static, because the DLC numbers
are hardcoded.
This is a first attempt at the Infineon modem support. The support
is limited since it doesn't handle the setup of the multiplexer or
the different SIM states yet.
Marcel Holtmann
Marcel Holtmann