MC7430 Connection problem

Tue Oct 3 07:06:55 UTC 2017

On Tue, Oct 3, 2017 at 9:51 AM, Erik Kazandjian
<erik.kazandjian at accelleran.com> wrote:
> To be very honest we are developing  a cell ourselves and I see on the cell
> that the modem is attached. But now I also noticed if I reboot everything ,
> the Pi and the modem I see the modem atteching and when I ask for its
> current settings it responds with an IP address.
>
> This seems to work every time I put switch the modem from low power to
> online. Without any other qmi command.
>
> I was hoping that the SW driver would pickup the IP address from within the
> ATTACH accept and applied that to its interface.

The power-management settings on the MC74xx seem like something that
need taming.
Atm, I've simplified my flow to powering up the device, and just
plugging the modem in.
This flow works reliably everytime.

I have to check/stabilize other modem-flows like:
* what if I reboot the host device [ what happens ?] do I need to
issue a reset command so that the modem clears all internal state ?
* re-plugging the device seems to work, but some logic, like waiting
for the modem to register to the carrier needs to be interrupted ;
what if I plug back the modem before the cleanup of the original flow
finished ?
* what if i disable the connection ? do i put it into offline mode ?
do i issue a reset after that ?

I've noticed that resetting the device takes a while.
In that time, the usb0 & usb1 & cdc devices disappear for a while and come back.

>
> BR
>
> Erik
>
>
>
> On 10/03/2017 08:43 AM, Alexandru Ardelean wrote:
>>
>> On Tue, Oct 3, 2017 at 9:38 AM, Erik Kazandjian
>> <erik.kazandjian at accelleran.com> wrote:
>>>
>>> Hi,
>>>
>>> I managed to set an ip address on my interface and pass data once.
>>> However
>>> this was a lucky shot as I can not reproduce it.
>>>
>>> This is what I have done.
>>>
>>> I rebooted the pi
>>>
>>> ifconfig  wwan0  down
>>> echo Y > /sys/class/net/wwan0/qmi/raw_ip
>>> ifconfig  wwan0  up
>>>
>>> The strange thing that I noticed here is that my wwan0 interface no
>>> longer
>>> has a hw address ?
>>>
>>> wwan0     Link encap:UNSPEC  HWaddr
>>> 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
>>>            UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500 Metric:1
>>>            RX packets:0 errors:0 dropped:0 overruns:0 frame:0
>>>            TX packets:54 errors:0 dropped:0 overruns:0 carrier:0
>>>            collisions:0 txqueuelen:1000
>>>            RX bytes:0 (0.0 B)  TX bytes:11670 (11.3 KiB)
>>>
>>> wwan1     Link encap:Ethernet  HWaddr 86:10:a5:53:2a:0a
>>>            inet addr:169.254.80.97  Bcast:169.254.255.255
>>> Mask:255.255.0.0
>>>            inet6 addr: fe80::5d36:cbca:3f4f:c40f/64 Scope:Link
>>>            UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
>>>            RX packets:0 errors:0 dropped:0 overruns:0 frame:0
>>>            TX packets:56 errors:0 dropped:0 overruns:0 carrier:0
>>>            collisions:0 txqueuelen:1000
>>>            RX bytes:0 (0.0 B)  TX bytes:12074 (11.7 KiB)
>>>
>>> I set modem in standby, this causes the modem to dettach (as it
>>> automatically attaches when it comes up)
>>>
>>> qmicli -d /dev/cdc-wdm0 --dms-set-operating-mode=low-power
>>>
>>> Then I bring it online again
>>>
>>> qmicli -d /dev/cdc-wdm0 --dms-set-operating-mode=online
>>>
>>> This command causes the modem to attach again. So then I stop the network
>>>
>>> qmicli -d /dev/cdc-wdm0  --wds-stop-network=disable-autoconnect
>>>
>>> Network cancelled... releasing resources
>>> [/dev/cdc-wdm0] Network stopped
>>>
>>> When I than try to setup the network mannually (not usin gqmi-network) I
>>> get
>>> the following message
>>>
>>> qmicli -d /dev/cdc-wdm0 --wds-start-network=apn='internet',ip-type=4
>>> --client-no-release-cid
>>>
>>> error: couldn't start network: QMI protocol error (26): 'NoEffect'
>>> [/dev/cdc-wdm0] Client ID not released:
>>>      Service: 'wds'
>>>          CID: '42'
>>>
>>> Which makes the following call fail.
>>>
>>> qmicli -d /dev/cdc-wdm0  --wds-get-current-settings
>>> error: couldn't get current settings: QMI protocol error (15):
>>> 'OutOfCall'
>>
>> You need to wait for the device to register to a network.
>> Using --nas-get-serving-system to check that it says "registered" at
>> Registration state:
>> I suspect that is why you get NoEffect when you connect via
>> wds-start-network, and OutOfCall when you check settings.
>>
>> I've noticed that MC7430 takes quite some time [ compared to MC73xx ]
>> to connect to a tower.
>> Not sure why though.
>>
>> Alex
>>
>>>
>>> Using the same set of commands I managed to get it working once. So I'm
>>> still not clear how I can reproduce the successfull case
>>>
>>> Thanks for any help
>>>
>>> Erik
>>>
>>>
>>>
>>>
>>>
>>>
>>> On 10/02/2017 10:45 PM, Bjørn Mork wrote:
>>>>
>>>> Aleksander Morgado <aleksander at aleksander.es> writes:
>>>>
>>>>> Ah, true... then no idea why it didn't allow updating that... first
>>>>> time I've seen this.
>>>>>
>>>>> Erik, can you manually run this?
>>>>> $ sudo -s
>>>>> # echo Y > /sys/class/net/wwan0/qmi/raw_ip
>>>>
>>>> The driver will refuse to change mode if the netdev is running.  I.e. if
>>>> the interface is up.  It should log an error and the write should return
>>>> -EBUSY in this case.
>>>>
>>>> The driver will also notify other drivers of the upcoming type change,
>>>> allowing them to block it.  This will prevent mode change if you have
>>>> added the wwanX device to a bridge for example (which isn't a good idea
>>>> for a raw ip device).  The sysfs write should still return an
>>>> appropriate error code.
>>>>
>>>>
>>>>
>>>>
>>>> Bjørn
>>>
>>>
>