* add type annotations in-line with PEP484
* convert existing documentation to follow the
"Google Python Style Guide" format understood by
the sphinx.ext.napoleon' extension
* add much more documentation all over the code base
Change-Id: I6ac88e0662cf3c56ae32d86d50b18a8b4150571a
According to 3GPP TS 27.007, sections 8.17 and 8.18, the modem
may *optionally* provide Generic and/or Restricted SIM Access
to the TE (Terminal Equipment) by means of the AT commands.
This basically means that a modem can act as a card reader.
Generic SIM Access allows the TE to send raw PDUs in the format
as described in 3GPP TS 51.011 directly to the SIM card, while
Restricted SIM Access is more limited, and thus is not really
interesting to us.
This change implements a new transport called ModemATCommandLink,
so using it a SIM card can be read and/or programmed without the
need to remove it from the modem's socket. A downside of this
approach is relatively slow I/O speed compared to PC/SC readers.
Tested with Quectel EC20:
$ ./pySim-read.py --modem-dev /dev/ttyUSB2
Change-Id: I20bc00315e2c7c298f46283852865c1416047bc6
Signed-off-by: Vadim Yanitskiy <axilirator@gmail.com>
