Huawei E3276 problem

[Tommy Cheng]

The initial submitted cdc_ncm driver (2010/12/07 net.git) and 

the latest submitted cdc_ncm driver(2012/08/04 net.git) are not
working.  The driver can't bind to E3276 because of "bind() failure".

The driver only works for me is from the below link.  That driver
seems to be very similar to the initial subnitted one.  I'm still trying
to find out why.


http://www.spinics.net/lists/linux-usb/msg32494.html




----- Original Message -----
From: Bjørn Mork <bjorn at mork.no>
To: Tommy Cheng <tommy7765 at yahoo.com>
Cc: "libqmi-devel at lists.freedesktop.org" <libqmi-devel at lists.freedesktop.org>
Sent: Tuesday, November 13, 2012 4:30 PM
Subject: Re: Huawei E3276 problem

Tommy Cheng <tommy7765 at yahoo.com> writes:

> The cdc_ncm driver I tried is from the following link.
> http://www.spinics.net/lists/linux-usb/msg32494.html
>
> This driver is working OK, but sometimes "CDC: unexpected notification 0x1"
> will show up.

That's interesting. 0x01 is "response available", and is what you'd get
when the modem wants to send a message on the control channel. So this
means that there are some unsolicited (since we don't send any requests)
control messages here.  We could dump these messages by using the
cdc_wdm driver, but it won't really help much as we don't know the
protocol used.

> By the way, the cdc_ncm driver from GIT is NOT working for me either.
> cdc_ncm driveit will get "bind() failure"when doing usb_driver_claim_interface.

Ah, OK, that explains a lot.

Could you try to find out why?  I assume the GIT version you are using
is something before net-next, where we have a lot of cdc_ncm changes
queued for the cdc_mbim support?  Which version are you using when this
works? 

I would very much like to have these devices supported by the mainline
driver, if that is possible.  And the fact that you have it working with
a prior version demonstrates that it is.

> Here are the steps on how I do it.
> ==========================================
> # insmod /tmp/cdc_ncm.ko 
> usb 1-1: MAC-Address: 0x0c:0x5b:0x8f:0x27:0x9a:0x64


Ugh.  Ok, that ugly mac printout sort of helps pinpointing your release
as this was fixed in February and included in Linux 3.4.  So you are
using something older than v3.4.

I'll go look at what else has changed since then.

> #usb 1-1: CDC: unexpected notification 0x03!

This is very odd.  0x03 is not a notification defined by CDC NCM.  The
only supported ones are

NETWORK_CONNECTION 00h
RESPONSE_AVAILABLE 01h
CONNECTION_SPEED_CHANGE 2Ah


Bjørn