Odd QMI devices - ZTE MF60

[Aleksander Morgado]

> This shows up without even registering any QMI_WDS client.  I assume
> it's an attempt from the firmware to trick any driver/application into
> believing it's already connected, and therefore avoid any connection
> attempts.
> 
> We could choose to let ourselves beeing tricked here, avoiding any
> device specific quirk and just believe the indication instead.  Would
> that work?
> 

If we create a WDS client before the "Set Instance ID" it will get the
broadcast WDS indication, and the connection manager can try to process
that. Quite depends on how the connection manager wants to behave I
guess, I would personally try to get tricked only if that doesn't
complicate other things around.

> Yuck, I just noticed a couple more bugs in the firmware's QMI_WDS
> interception: It responds (using allowed 0x0001 and 0x0023 commands) to
> any client ID, allocated or not.  And it crashes on unknown QMI_WDS
> commands instead of responding with QMI_ERR_INVALID_QMI_CMD.
> 
> Based on the last observation, I assume that the problem is that the
> firmware crashes on any QMI_WDS command it doesn't implement.  And it
> doesn't implement many...  It's tempting to guess that a firmware
> engineer has observed the Windows driver and implemented exactly those
> commands necessary to trick Windows into believing there is a
> connection.
> 
> You gotta love that development model ;-)

Look, it worked for him, all his tests passed, so it gotta be right :-)

-- 
Aleksander