[PATCH v2] Add custom flow control settings for Telit HE910, UE910, UL865

[Aleksander Morgado]

On Fri, Mar 13, 2015 at 5:12 PM, Daniele Palmas <dnlplm at gmail.com> wrote:
>>> >> Not sure about UE910 / UL865, we probably want to ignore a few
>>> >> interfaces on HE910 as these ports aren't responding to AT probe and
>>> >> don't want to waste extra time probing them. I can rebase my patch
>>> >> earlier to all the following rules. What do you think?
>>> >>
>>> >>
>>> >> ATTRS{idVendor}=="1bc7", ATTRS{idProduct}=="0021",
>>> >> ENV{.MM_USBIFNUM}=="02", ENV{ID_MM_PORT_IGNORE}="1"
>>> >> ATTRS{idVendor}=="1bc7", ATTRS{idProduct}=="0021",
>>> >> ENV{.MM_USBIFNUM}=="04", ENV{ID_MM_PORT_IGNORE}="1"
>>> >> ATTRS{idVendor}=="1bc7", ATTRS{idProduct}=="0021",
>>> >> ENV{.MM_USBIFNUM}=="08", ENV{ID_MM_PORT_IGNORE}="1"
>>> >> ATTRS{idVendor}=="1bc7", ATTRS{idProduct}=="0021",
>>> >> ENV{.MM_USBIFNUM}=="0a", ENV{ID_MM_PORT_IGNORE}="1"
>>> >> ATTRS{idVendor}=="1bc7", ATTRS{idProduct}=="0021",
>>> >> ENV{.MM_USBIFNUM}=="0c", ENV{ID_MM_PORT_IGNORE}="1"
>>> >
>>> > Daniele, what do you think about this? I don't have any of those
>>> > modems to check that myself.
>>> >
>>> > If the ports don't reply to AT or anything, then what are those ports
>>> > for? (just wondering) I guess one may be a GPS data port, but what
>>> > about the others? Also, what's the kernel driver managing those ports?
>>> >
>>>
>>> HE910/UE910/UL865 use the standard cdc-acm driver.
>>>
>>> Some useful information can be found in "HE910/UE910/UL865 Families Ports
>>> Arrangements User Guide" (it can be found in Telit website).
>>>
>>> The AT command AT#PORTCFG sets the ports behaviour.
>>>
>>> For the factory setting (#PORTCFG=1) only the two interfaces I put in
>>> the udev rules are linked to AT parsers, so I think it is safe to
>>> ignore the other
>>> ones.
>>>
>>> The other ports are used with different #PORTCFG settings (for modem traces,
>>> gps, additional AT parser, appzone...)
>>
>> Yeah, this is what I was afraid of, and one reason why we have the MM
>> probing behavior.  The port configuration can often be changed in
>> firmware (or by a firmware update) so the same static udev rules cannot
>> always be used.
>>
>> *however*, we can ship a set of default udev rules and describe the port
>> configuration it should be used for, and then individual users or
>> packagers can override those rules for their specific use-cases if they
>> wish.  eg, we could have a 77-telit-910-portcfg-1.rules and
>> 77-telit-910-portcfg-5.rules which correspond to each #PORTCFG layout
>> for each modem?
>>
>
> This could be a possible solution: the default could be the factory
> setting, then we can identify the most important #PORTCFG layouts
> among the 12 provided by the command.

What I wonder is how often vendors change the default factory setting
when shipping these modems. If this is something rare, maybe we
shouldn't care at all. If this is something common, then we shouldn't
have the udev tags and instead query PORTCFG and go on from there.

-- 
Aleksander
https://aleksander.es