Avoiding --device-open-mbim in qmicli and qmi-firmware-update

[Bjørn Mork]

Aleksander Morgado <aleksander at aleksander.es> writes:

> Hey,
>
> How about we change libqmi so that by default it will check which
> kernel driver exposed the cdc-wdm port, and then use QMI directly (if
> qmi_wwan) or QMI over MBIM (if cdc_mbim)? That would allow us to
> obsolete --device-open-mbim for good.
>
> There were cases where devices would support both protocols directly,
> depending on which was first used, but I don't think this is something
> we should even spend much time on supporting.
>
> Comments?

I like it.  I forget to use that option all the time.  And I don't see
any reason why you cannot trust the driver.

Yes, you could in theory need to talk QMI directly to a modem having
MBIM descriptors, because the modem does protocol probing.  But I don't
see that as something that can be automatically handled anyway.  And you
can still work around this even with fully automatic libqmi support, by
manually switching drivers.  The other way won't work, though, as the
cdc_mbim driver will refuse to bind to a QMI device.  Not a big
deal. You shouldn't do this anyway and I cannot imagine any real use
case.

So please: Do the auto-thing and obsolete the option.


The only issue I can see is that using libqmi on an MBIM modem might be
confusing without the explicit MBIM request.  But this could be handled
with a short message telling the user what's going on. You don't want
users to expect this to work with *any* MBIM modem, complaining when it
doesn't :)


Bjørn