problem with huawei e355 with xubuntu 14.04 and modemmanager 1.0.0

[Aleksander Morgado]

On Tue, Apr 22, 2014 at 8:16 AM, som <drsoumalya-mm at yahoo.co.in> wrote:
> i am using xubuntu 14.04 with modemmanager 1.0.0 version and i am having a
> problem with huawei E355 modem [1]. in (x)ubuntu 12.04.3, and 13.04 , this
> device used to work by default; just a plug and play device. both of them
> used to have linux 3.8 kernel series.
>
> huawei E355 is a device with 1xethernet-over-usb connection and 5xwifi
> connection creator.
>
> ideally, after plugging the device into a desktop/laptop, the network
> manager applet should show two connections- one under the "wired connection"
> heading and the other under the "wireless connection" heading. both
> (x)ubuntu 12.04.3 and 13.04 performed as expected.
> unfortunately, that is not happening with post 3.8 kernel series; ie,
> (x)ubuntu 13.10 onwards. only the "wireless connection" option is visible;
> but not the "wired connection" part. ethernet-over-usb is not working-
> neither in xubuntu 13.10 nor in in 14.04, LTS.
>
> possible reason: cdc_ncm part of the kernel was changed beyond 3.8 series
> but the changes were  not represented in the modem manager.
>
> reasons for thinking so:
> in a german user forum[2], it was suggested first. they recompiled the 3.11
> kernel and deactivated the changes made in cdc_ncm after 3.8 kernel series.
> and, suddenly the "wired connection" option is visible again in xubuntu
> 13.10.
> unfortunately, this is not a permanent solution; and anyway its not working
> in xubuntu 14.04 LTS. how to solve this problem permanently and in the LTS
> version in particular?
>
> any help will really be appreciated.
>
> links:
> [1] -> http://www.huaweidevice.co.in/Products/MobileBroadband/E355.php
> [2] ->
> http://forum.ubuntuusers.de/topic/huawei-e355-als-kabelnetzwerk-einbinden-wwan0-/
> launchpad bug:
> https://bugs.launchpad.net/ubuntu/+source/modemmanager/+bug/1309054


commit 1f84eab4ad73bcb7d779cba65291fe62909e373f
Author: Bjørn Mork <bjorn at mork.no>
Date:   Wed Feb 27 03:08:58 2013 +0000

    net: cdc_ncm: tag Huawei devices (e.g. E5331) with FLAG_WWAN

    Tag all Huawei NCM devices as WWAN modems, as we don't know of any which
    are not.  This is necessary for userspace clients to know that the device
    requires further setup on e.g. an AT-capable serial ports before
    connectivity is available.

The device is truly a WWAN modem, but again it doesn't require any
ModemManager setup. Dan, can we maybe update NetworkManager to
initially ignore all WWAN flagged devices but only if ModemManager
takes them afterwards in a modem object? In other words, if MM doesn't
end up taking the interface (hum.. how to notify that?) then NM can
try to expose it as a USB net interface...

I also wonder whether with newer kernels and the huawei_cdc_ncm driver
we will get an AT /dev/cdc-wdm port.

-- 
Aleksander
https://aleksander.es