QMI disconnection errors detection in Netgear AC341U

Aleksander Morgado aleksander at aleksander.es
Tue Sep 5 20:26:11 UTC 2017


The Netgear AC341U is a QMI device that comes with autoconnect enabled (and disabling it doesn't look possible, firmware may even crash and power cycle itself). I suspect that due to autoconnect being enabled, the packet service indications aren't sent as we expect them, in particular to detect network initiated disconnections.

If we don't get reliable packet service indications reporting disconnections, we may end up with ModemManager saying the modem is connected while the WWAN interface isn't really usable. To avoid this situation, we hook up two new places where we can detect the disconnection reported: either in the GetCurrentSettings step during the connection attempt (seen a couple of times where this is the case), or otherwise in the periodic Statistics loading logic (much more frequent).


  [PATCH 1/2] bearer-qmi: detect early disconnections when getting current settings
  [PATCH 2/2] bearer-qmi: detect disconnections when loading stats

More information about the ModemManager-devel mailing list