ZTE MF683

[Bjørn Mork]

"Shawn J. Goff" <shawn7400 at gmail.com> writes:

> So far, my dev system doesn't like 3.6. I have been backporting
> qmi-wwan and cdc-wdm to 2.6.39. As of the 7th, I had everything, so I
> think the only commit I'm missing right now is "USB: cdc-wdm: fix
> wdm_find_device* return value". The source is here if you're
> interested: https://bitbucket.org/accelecon/linux-at91/changesets.

That is definitely interesting!  Especially if you can get it to work
:-)  Thanks for doing that.

> Here are some printk messages that come out when I manually bind the
> driver in that kernel:
>
> [  597.925000] qmi_wwan: probe of 1-2:1.0 failed with error -22
> [  597.932500] qmi_wwan: probe of 1-2:1.1 failed with error -22
> [  597.937500] qmi_wwan: probe of 1-2:1.2 failed with error -22
> [  597.945000] qmi_wwan: probe of 1-2:1.3 failed with error -22


Yes, those 4 interfaces have no interrupt endpoint so they can be ruled
out.  Most likely serial ports all of them, where some are special
purpose ports like GPS NMEA, QCDM or other serial protocols.


> [  597.955000] qmi_wwan 1-2:1.4: cdc-wdm0: USB WDM device
> [  597.955000] qmi_wwan 1-2:1.4: wwan0: register 'qmi_wwan' at
> usb-atmel-ehci-2, WWAN/QMI device, 82:28:8e:37:92:dc
> [  597.960000] qmi_wwan 1-2:1.5: cdc-wdm1: USB WDM device
> [  597.960000] qmi_wwan 1-2:1.5: wwan1: register 'qmi_wwan' at
> usb-atmel-ehci-2, WWAN/QMI device, 82:28:8e:37:92:dc

OK, those are the two only likely candidates having an interrupt in and
bulk in + out endpoints.

> [  597.960000] qmi_wwan: probe of 1-2:1.6 failed with error -22

And the last interface is mass storage, so that is OK.

>
> As you can see, it created two pairs of devices. I tried
> --nas-get-signal-strength on both wdm devices:
>
> # qmicli --nas-get-signal-strength -d /dev/cdc-wdm0
> [  657.477500] qmi_wwan 1-2:1.4: unknown notification 32 received: index 4 len 2
> ###[Nothing for a long time, I sent SIGINT]
> cancelling the operation...
> error: couldn't create client for the 'nas' serv[  668.177500]
> qmi_wwan 1-2:1.4: Error in flush path: -32
> ice: CID allocation failed in the CTL client: Transaction timed out

I suspect interface #4 is really a serial port.  Can you do AT commands
on it if you use the option driver instead?


> # qmicli --nas-get-signal-strength -d /dev/cdc-wdm1
> **
> ERROR:qmi-utils.c:72:qmi_utils_read_guint8_from_buffer: assertion
> failed: (*buffer_size >= 1)
> Aborted


This is odd, but interesting.  I have no clue why you got that result,
but the fact that it didn't just time out probably means that you got
some response.  It doesn't necessarily mean that it is QMI though...

Are you able to do usb snooping on this device, using usbmon? Unless
something went wrong during the backport, I am wondering if this
interface does support CDC embedded commands, but embedding something
that is not QMI.

BTW, is this a big endian platform (sorry for my complete ignorance wrt
Atmel chips...)? 


Bjørn