[PATCH] Add DEVICE_OPEN_FLAG_DATA_FORMAT

[Bjørn Mork]

Robert Shade <robert.shade at gmail.com> writes:

> Some devices (like Sierra's MC7700 w/the latest AT&T firmware), default
> to a packet data format that's incompatable with qmi_wwan/usbnet.  This results
> in us being unable to get a DHCP address or otherwise use the virtual ethernet
> port.  Add DEVICE_OPEN_FLAG_DATA_FORMAT to set the data format
> to default (no-QoS) and data mode to ethernet when opening.

Explicitly setting the expected mode seems to be wise in any case.

But I am curious: What is the new default?  Raw IP and no QoS? Did
anyone find any use for the QoS mode, BTW?

I am asking because it seems we have to add some data interception hooks
to cdc_wdm to support MBIM, and I am playing with the idea to let the
qmi_wwan snoop on "Set Data Format" messages and just support whatever
mode you set.  It can most certainly be done, and it won't be much code
either.

Last time I played with the QoS mode I found it to be mostly useful for
crashing the firmware though....  But this is some time ago.


Bjørn