[PATCH 2/2] dell: removed ID_MM_TELIT_PORTS_TAGGED dependency

[Aleksander Morgado]

On Wed, May 10, 2017 at 4:34 PM, Carlo Lobrano <c.lobrano at gmail.com> wrote:
>> Could you gather debug logs using the Telit/Dell modem in 2 different
>> runs:
>>    * with the custom block setting cgmi_retries=0 and ati_retries=0 in
>> the Dell plugin (as in git master)
>>    * and without it (e.g. just removing that block)
>
>
>
> Ok, this is equivalent to test it once with MM master, and once with MM
> master but without Dell udev rule to tag Telit modems, right?

Yes

> The results are attached to this email

So, without the udev rule it takes 51s to probe all ports doing all
retries for all commands. With the udev rule in place it gets a bit
better, and takes 30s to do all port probing (you removed 6 AT
commands with the udev rule: 3 CGMI, 3ATI).

I'm tempted to say that instead of:
    ctx->gmi_retries = 3;
    ctx->cgmi_retries = 3;
    ctx->ati_retries = 3;

We could do:
    ctx->gmi_retries = 3;
    ctx->cgmi_retries = 1;
    ctx->ati_retries = 1;

The retries logic is in case the port needs some time to reply, so
probably doing the retries only for the first command would make
sense, and this would get us 4 commands removed for all.

But also, is there a modem that doesn't reply to AT+GMI at all? i.e.
just not replying anything? I doubt it, so we could also see if all
AT+GMI retries failed with a timeout error, and if so we just assume
it's not an AT port directly. This would actually have a better effect
than your patch, because we not only skip the CGMI or ATI commands,
but also the extra "AT"-only commands that I also see in the logs.

What do you think? I think the last approach could be very useful here.

-- 
Aleksander
https://aleksander.es