Leveraging GPS in MC7700

[Aleksander Morgado]

On Mon, Feb 6, 2017 at 1:00 PM, Adam Sherman <adam at sherman.ca> wrote:
> On 2017-02-06 04:21 AM, Aleksander Morgado wrote:
>>> The primary port was cdc-wdm0 in my previous message. What is changing?
>>> And I never seem to get the nice data I put in my previous messages.
>>>
>> Looks like QMI probing failed and MM didn't grab the cdc-wdm port?
>>
>
>>>
>>> So, as an attempt and kicking the card and driver, I suspended the
>>> system, then woke it up.
>>>
>
>>> The modem is now index 1, and mmcli says its primary port is back to
>>> cdc-wdm0. In addition, I got the fully loaded location capabilities back:
>
> So after a suspend/wake, it did grab the right port?
>

Yes, the cdc-wdm port was reprobed correctly after that.

>> The GPS receiver didn't get a position fix yet, so even if you enable
>> GPS raw source, it won't show anything until the fix is reported via
>> NMEA traces ($GPGGA IIRC).
>
> I left it overnight and it seems to have a fix, now.
>
> So, am I understanding correctly that there is no way to get GPS data
> via a serial device, with this card?
>

No, there is a way to do that, enabling the GPS receiver with AT
commands and processing the NMEA traces received from another TTY; it
just isn't implemented in ModemManager. We could implement the
"unmanaged gps" location support in the Sierra plugin to handle that
usecase.

-- 
Aleksander
https://aleksander.es