USB addresses change every time the device re-enumerates, while the path
reflects the physical topology of USB connections and stays persistent
unless the usb cabling is changed. Let's allow the user to specify the
path instead of the address to uniquely identify a given slot.
It seems that sometimes we get even an LIBUSB_ERROR_IO and failing on
errors breaks the application, while ignoring it works. Not sure why
that really is, but for now it increases reliability.
as soon as simtrace2-remotesim is started, we issue the command to
instruct the use of the remote SIM card and ask the modem to reset
itself (to start using the new remote sim).
In current implementations, we have one interface (with it's own
separate set of USB end-points) per slot. However, the USB protocol
already includes a slot-number in the header to be able to remove that
restriction in future versions.
Also, if the USB protocol is used remotely over a network, then we could
multiplex differnt slots from different USB interfaces into one stream
on the network side.
In order to prepare the data structures in the host program, let's
introduce that logical split there, too. Might seem a bit like
overkill, but I don't want to rewrite all code later...
We want to be able to use some code irrespective of the application
(emulation, tracing, ...), so let's split the transport struct out of
the cardem_instance.
The current protocol was card-emulation specific. The new protocol is
generic/flexible enough to accommodate both tracing and card emulation,
as well as modem control and other future extensions.
Rather than using the first available interface on the first available
device, we now have a "simtrace2-list" program that lists all compatible
interfaces on all configurations of all devices on the system
When we want to run multiple instances of the card-emulator (e.g. for
multi-modem/multi-card versions of the hardware), the code shouldn't be
using any global variables but have them per-instance.
We now auto-discover the end-point addresses based on the interface
descriptor. The user can also use the new "--interface" command line
argument to set a non-zero intrerface. In combination, this should
enable support for the remote-sim functionality on the second UART
on OWHW.
Harald Welte