Support for the Linux WWAN subsystem

Ramon Fontes ramonreisfontes at
Sun Aug 29 15:48:52 UTC 2021

Hello Aleksander,

> Is that wwan_hwsim integration to be able to create fake modems in
> userspace that are exposed via the new WWAN subsystem? If so, wouldn't
> they already be supported by the current ModemManager, which supports
> the new WWAN subsystem?

I suppose the answer should be "yes they are supported by the current
MM". However, mmcli returns no modems.

mmcli -L
No modems were found

> Please correct me if I'm wrong; openairinterface5g allows you to
> simulate/implement the radio and 3GPP protocol side of a UE. But there
> is no AT/QMI/MBIM control protocol implemented in openairinterface5g,
> or is there?

Yes. However I think we could leverage openairinterface5g by emulating
the radio and 3GPP protocol too. My experience with mac80211_hwsim and
more recently with mac802154_hwsim are very interesting. They
basically allow us to run any application/implementation and move them
to the real world with few or even no modifications. Why not have
something similar with wwan_hwsim and 4G/5G? :)

Ramon Fontes

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