[RFC PATCH] broadband-modem-mbim: refine access technology updates

[Ben Chan]

On Wed, May 14, 2014 at 12:08 PM, Dan Williams <dcbw at redhat.com> wrote:
>
> Looks like the right approach.  The only thing I'd worry about is
> whether we reliably get notifications for packet service at the right
> times?  Should the patch be more aggressive about clearing
> self->priv->HADC to ensure it isn't stale?  For example, perhaps the
> device doesn't send a Packet Service "off" notification after being
> explicitly disconnected because the firmware is stupid and assumes that
> since the host asked for disconnection, it knows to clean up the HADC.
>

This seems tricky. The modem can still attach to a packet service
without activating an IP session. ModemManager currently doesn't
explicitly detach the packet service upon a client / network initiated
disconnect. So any detach action should come from the modem
internally, which means we would expect the modem to "Do The Right
Thing (tm)" and notify us via a MBIM_CID_PACKET_SERVICE notification.