Netgear Aircard 341U in QMI mode, switching to 802.3

[Aleksander Morgado]

Hey,

This device has multiple firmware versions, one of them QMI based.

Interestingly the device always boots up with the wwan in raw-ip mode,
and using CTL Set Data Format to 802.3 *never* succeeds...

# qmicli -d /dev/cdc-wdm0 --dms-noop
--device-open-net="net-802-3|net-no-qos-header" --verbose

The CTL Set Data format either returns SUCCESS but with "raw-ip" in
the Protocol TLV (i.e. it didn't change anything) or otherwise it
returns an error.

In order to switch the wwan to 802.3 you can use --wda-set-data-format:


# qmicli -d /dev/cdc-wdm0 --wda-get-data-format
[/dev/cdc-wdm0] Successfully got data format
                   QoS flow header: no
               Link layer protocol: 'raw-ip'
  Uplink data aggregation protocol: 'disabled'
Downlink data aggregation protocol: 'disabled'
                     NDP signature: '0'
  Uplink data aggregation max size: '0'
Downlink data aggregation max size: '0'

# qmicli -d /dev/cdc-wdm0 --dms-noop
--device-open-net="net-802-3|net-no-qos-header"
(success returned, but didn't really work as we can see in the next command)

# qmicli -d /dev/cdc-wdm0 --wda-get-data-format
[/dev/cdc-wdm0] Successfully got data format
                   QoS flow header: no
               Link layer protocol: 'raw-ip'
  Uplink data aggregation protocol: 'disabled'
Downlink data aggregation protocol: 'disabled'
                     NDP signature: '0'
  Uplink data aggregation max size: '0'
Downlink data aggregation max size: '0'

# qmicli -d /dev/cdc-wdm0 --wda-set-data-format=802-3
[/dev/cdc-wdm0] Successfully set data format
                        QoS flow header: no
                    Link layer protocol: '802-3'
<--------------------------------
       Uplink data aggregation protocol: 'disabled'
     Downlink data aggregation protocol: 'disabled'
                          NDP signature: '0'
Downlink data aggregation max datagrams: '0'
     Downlink data aggregation max size: '0'

We need to handle this in ModemManager automatically...

-- 
Aleksander
https://aleksander.es