Issues with Netgear 340U latest firmware

[Dan Williams]

On Wed, 2014-08-13 at 11:24 -0700, Gopakumar Choorakkot Edakkunni wrote:
> Hi,
> 
> I have a linux system running libqmi-1.0 which used to work just fine
with
> the previous revision of Netgear. But after I upgraded the firmware to
the
> version mentioned in the subject, the wwan interface gets created just
> fine. If I do a tcpdump I can see DHCP packets going out of wwan, but
there
> is absolutely nothing coming back in on wwan (ifconfig wwan Rx packets
is
> zero).
> 
> root:/# qmicli -d /dev/cdc-wdm0 --dms-get-revision
> [/dev/cdc-wdm0] Device revision retrieved:
>     Revision: 'NTG9X15C_01.13.12.13 r18963 ntgrbc-fwbuild1 2014/05/26
> 12:30:18'
> 
> In the netgear website (
> http://support.netgear.com/product/AirCard+340U+$28AT$26T$29), they
have a
> new Gobiserial.c driver for Linux, does anyone know if theres anything
in
> there that needs to be brought into libqmi to get it working ? Or does
the
> latest libqmi have anything that might already take care of this ?

What is the USB VID/PID of your device?  There are apparently a few of
them depending on what mode the modem is in.

Two possible theories:

a) newer devices, especially Sierra ones, sometimes implement multiple
QMI/Ethernet interfaces, but only some of those actually work for data.
That could be what you're hitting here.  We'd need the VID/PID to figure
this out though.

b) On "9x15" devices, the Netgear GobiNet driver uses the WDA service's
Set Data Format call instead of the CTL service.  Not sure if that makes
a difference here or not, but maybe new devices expect the WDA mechanism
instead, and so the data format is not getting switched to Ethernet?

(Also it's cute that they grabbed Bjorn's header fixup workaround and
added it to the GobiNet driver...)

Bjorn: I see that the Sierra drivers expect the following layout

Serial:
1199:68A2 - blacklisted: 8, 10, 11, 19, 20
1199:68C0 - blacklisted: 8, 10, 11
1199:9057 - blacklisted: 0, 1, 5, 8, 10, 11 ("Netgear AC341U IPT2 mode")

Net:
1199:68A2 - 8, 10, 19 ("MDM9x15 PDNs")
1199:68C0 - 8, 10, 19
1199:9057 - 8, 10, 11

Which means that qmi_wwan is missing:

1199:68a2: 10
1199:68c0: 19
1199:9057: 10, 11

No idea whether adding these to qmi_wwan would be useful or not, you've
done more work than I with these devices, and I'm not sure where we
landed on whether or not to expose the non-functional QMI interfaces
through qmi_wwan.

Dan