Architectural-Queries on integrating Sierra-MC8090 with Linux

From: Ajay Garg
Date: Thu Aug 11 2016 - 04:53:21 EST


Hi All.

Have posted the question on Sierra-forums
https://forum.sierrawireless.com/viewtopic.php?f=117&t=9898
Posting it here as well, as the activity there is relatively low, and
this is where all the kernel-guys hand :)


I am using a Ubuntu interfaced with a Sierra-MC8090 module.

Right now MC8090 is identifed as a network-interface on Linux, made
possible by the usage of "sierra" (serial-driver) and "sierra_net"
(direct-ip usb-to-wwan driver) kernel-drivers. This "mostly" works,
except that we, in the user-application, are not able to access the
serial-file /dev/ttyUSB3 (this file is in constant usage by
/usr/sbin/ModemManager).

Now, my question is, if we disable loading the "sierra_net" driver,
and use just "sierra" driver to communicate on the serial-port, will
using the Sierra-Linux-QMI-SDK do the job? In particular,

*
I understand that we will now have exclusive access (please correct me
if I am wrong) to the serial-port /dev/ttyUSB3.

*
How to do we create a socket to a particular server-port using the
QMI-SDK? I can see in the examples that we can start a data-call for a
profile (ConnectGSM.c), but I am unable to find how to instantiate a
socket through which we can do regular reads/writes.


Will be grateful to hear back from someone.


Thanks and Regards,
Ajay