Hi Michael,

Re-adding JH and mailing lists to conversation...

On 19/08/2019 10:00, Michael Nazzareno Trimarchi wrote:
> Hi
> 
> On Mon, Aug 19, 2019 at 9:51 AM Jonas Bonn <jonas@norrbonn.se> wrote:
>>
>>
>>
>> On 19/08/2019 09:36, Michael Nazzareno Trimarchi wrote:
>>> Can be chattering and rush current? Even are you sure that you don't have
>>> some reset our of the ofono service that send an at command that
>>> restart the modem?
>>
>> Just to try to prevent us from going down the wrong rabbit hole here:
>> i)  The modem is a QMI device so there are no AT commands being sent
> 
> Ok, so the uart used as ttyUSB0 and ttyUSB1 they don't support any AT command?
> Is qmi part only the network interface?

ttyUSB0 and ttyUSB1 _do_ support AT commands, but are complementary to 
the QMI interface which is a complete communication channel to the modem 
in itself.  The network interface is _only_ for the QMI channel:  the 
network packets are carried on a dedicated endpoint of the USB interface 
supporting QMI.

I think the question of QMI vs AT is moot here.  Internally the modem 
does pretty much the same thing; it's just the interface that looks a 
bit different.

In JH's case, only the 'qmimisc' device and the 'network' interface are 
in play via ofono.  These are separate endpoints on a single USB 
interface, all managed by the qmi-wwan driver in the kernel.

/Jonas