Re: [RFC PATCH 0/2] gemalto: netmon driver

[Denis Kenzior <denkenz@gmail.com>]

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Hi Sergey,

On 1/10/21 1:44 PM, Sergey Matyukevich wrote:
> Hello Denis and all,
> 
> This patch series implements netmon driver for gemalto modems that are
> able to provide basic measurements using AT+CQS and AT^SMONI commands.
> 
> This patch series is intendedly marked as RFC. In addition to general

I guess you mean intentionally here...

> feedback for this v1 I would like to clarify the right way to handle
> negative values that can be returned by modem. For instance, this

So the short answer is: You're not supposed to even have negative numbers in AT 
commands.  And since oFono follows 27.007, which is itself based on AT commands, 
negative numbers do not really exist at the API level.

Refer to ITU v.250 Section 5.4.2.1 "Numeric constants".  Strings are also 
supposed to be formatted in a certain way, which the firmware isn't doing 
properly either...  The fact that you have to resort to using 
next_unquoted_string is kind of telling.

> is the case for the values measured in dBm including EC/n0 and RSCP.
> Currently such values are discarded by CELL_INFO_DICT_APPEND macro.

I would guess your best bet would be to re-scale from what Gemalto firmware 
reports into something that 27.007 recommends.  You may have to refer to 27.007, 
Section 8.69 to see what the scale is according to 3GPP.

Regards,
-Denis