MC7455 can't transmit TCP data

[David McCullough]

Hi dailijin,

We had similar issues and just used the qmi_wwan driver from the latest
kernel.  Its pretty easy to retro fit to older kernels,

Do note however that where I used to get dhcp bearers from the MC7354
I am now getting static bearers.

Cheers,
Davidm

Dan Williams wrote the following:
> On Wed, 2016-10-26 at 16:51 +0800, dailijin wrote:
> > 
> > Hi All,
> > 
> > 
> > I am testing MC7455 on Linux based on kernel 3.8, I have patched
> > usbnet and qmi_wwan driver, the MC7455 modem can get  connected.
> > But can't transmit TCP data. The modem information as below.
> > ATI
> > Manufacturer: Sierra Wireless, Incorporated
> > Model: MC7455
> > Revision: SWI9X30C_02.05.07.00 r5154 CARMD-EV-FRMWR2 2015/12/04
> > 22:23:15
> > MEID: A00000670DEA2A
> > ESN: 12807659625, 8074E069
> > IMEI: 359072060229115
> > IMEI SV:  3
> > FSN: LQ631307870110
> > +GCAP: +CGSM
> > OK
> > 
> > 
> > Is there anyone encounter this issue?
> 
> This is likely a raw-ip versus 802-3 issue, the patches for which
> landed way, way after 3.8.  Have you patched the qmi_wwan driver in
> your kernel with recent improvements, or is it a vanilla 3.8 qmi_wwan?
> 
> In short: many new QMI devices no longer support "ethernet" mode, but
> use raw-ip that skips the pointless ethernet framing.  There are kernel
> enhancements required to make that work, and they landed long after
> 3.8.
> 
> Dan
> 
> > 
> > Thanks
> > 
> > 
> > 
> > 
> > --
> > 
> > Best Regards,
> > Dai,Lijin
> > _______________________________________________
> > libqmi-devel mailing list
> > libqmi-devel at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/libqmi-devel
> _______________________________________________
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> libqmi-devel at lists.freedesktop.org
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-- 
David McCullough,  davidm at spottygum.com,   Ph: 0410 560 763