u-blox TOBY-R200 Intermittent Long Registration on Simple Connect

[Aleksander Morgado]

On Mon, Apr 30, 2018 at 10:45 PM, Dan Williams <dcbw at redhat.com> wrote:
> On Mon, 2018-04-30 at 20:09 +0000, Matthew Starr wrote:
>> > -----Original Message-----
>> > From: Aleksander Morgado [mailto:aleksander at aleksander.es]
>> >
>> > >
>> > > I don't understand why there is a 20 second timeout.  Couldn't
>> > > you just test
>> >
>> > the AT interface right away with 'AT' instead of waiting a timeout
>> > and then
>> > trying it.  Also 20 seconds is a long time.  Couldn't a much
>> > shorter timeout be
>> > put in with some message sent to the modem to get it to respond
>> > (like 'AT')
>> > and do that several times to add up to 20 seconds.  This seems like
>> > it would
>> > be much quicker in cases where the modem did not respond
>> > immediately
>> > and might resolve this issue.
>> > >
>> >
>> > That 20s timeout is really an artifact added for the TOBY-L4, to
>> > wait
>> > for the +READY URC it sends if the port is detected via hotplug
>> > events. It's actually just to make it quicker the probing in the
>> > TOBY-L4. This should be therefore something specific for the TOBY-
>> > L4
>> > and not something generic for all u-blox modems... sorry for that
>> > :/
>> >
>> > I'll gladly accept a patch that makes this 20s timeout something
>> > specific for the TOBY-L4 ;)
>>
>> I changed that timeout to 2 seconds and it resolved the 20 second
>> timeout I was seeing.  Now as you said it needs to be something
>> specific for the TOBY-L4.  At this early of a point in registration
>> you haven't read the model number yet since communication hasn't been
>> established.  The only way I can think of detecting the TOBY-L4 is
>> using the USB product ID.
>>
>> Is there a function that allows obtaining the USB product ID that can
>> be used in the context of the wait_for_ready() function in the
>> plugins/ublox/mm-plugin-ublox.c file?  I tried the
>> mm_port_probe_get_product() function called within the
>> wait_for_ready() function, but just got (null) returned.
>>
>> Do you know if the TOBY-L4 has a unique USB product ID?  If so, do
>> you know what it is?
>
> Could do it through udev tags too; eg tag TOBY-L4 in the udev rules as
> needing a larger timeout, but all the rest get a shorter one.
>

Yes, I was thinking in udev tags as well. For the TOBY-L4:
ATTRS{idVendor}=="1546", ATTRS{idProduct}=="1010"

-- 
Aleksander
https://aleksander.es