EM9190 randomly dial fail

[Aleksander Morgado]

Hey,

> I am testing Sierra 5G modem EM9190. my kernel  version is V4.4.13 and use the default driver cdc_mbim.ko.  the modem randomly can't dial success after I reboot system.
>
> I checked AT command 'AT!GSTATUS' and confirm the modem can connect cell station successfully, but mbim-network always execute fail.  the error log is "error: couldn't open the MbimDevice: Failure".
>
> I am using libmbim version  1.14.0. do you any guys encounter the same issue?
>
> [10.12.32.138]# mbimcli -d /dev/cdc-wdm3 --query-connection-state -v
> [22 Apr 2021, 08:41:38] [Debug] opening device...
> [22 Apr 2021, 08:41:38] [Debug] [/dev/cdc-wdm3] Queried max control message size: 4096
> [22 Apr 2021, 08:41:38] [Debug] [/dev/cdc-wdm3] Sent message...
> <<<<<< RAW:
> <<<<<<   length = 16
> <<<<<<   data   = 01:00:00:00:10:00:00:00:01:00:00:00:00:10:00:00
>
> [22 Apr 2021, 08:41:38] [Debug] [/dev/cdc-wdm3] Sent message (translated)...
> <<<<<< Header:
> <<<<<<   length      = 16
> <<<<<<   type        = open (0x00000001)
> <<<<<<   transaction = 1
> <<<<<< Contents:
> <<<<<<   max control transfer = 4096
>
> [22 Apr 2021, 08:41:40] [Debug] [/dev/cdc-wdm3] Received message...
> >>>>>> RAW:
> >>>>>>   length = 16
> >>>>>>   data   = 01:00:00:80:10:00:00:00:01:00:00:00:02:00:00:00
>
> [22 Apr 2021, 08:41:40] [Debug] getting open done result failed: closed
> error: couldn't open the MbimDevice: Failure
>

Are you running that command as part of a script or something? If you
run mbimcli without using the --no-close and --no-open options
carefully, I assume you could get in such a situation quickly.

Have you tried to run ALL your mbimcli commands with the '-p' option
(to run through the proxy). When running with the proxy, it's the
proxy itself the one who keeps track of the open/closed MBIM session.

And another question, when you reboot your system, is the EM9190 also
power cycled? or is it kept powered? Maybe the MBIM session is kept
open in the device while the host thinks it should be closed?

You'll need to investigate a bit more following those hints :) Please
let us know what you discover.

-- 
Aleksander
https://aleksander.es