Re: The role of connection manager
by Grant Erickson
On Mar 1, 2019, at 12:00 PM, JH <jupiter.hce(a)gmail.com> wrote:
> Thanks Julien and Robert, I have already determined to use the oFono
> and ConnMan, I have been long advocate to ask my colleagues to
> consider using connection manager, your comments even strengthen my
> arguments for me to convince my colleagues.
>
> It is pity that our device is small with about 125 MB flash and about
> 250 MB ram which cannot fit the Debian 9 armhf, we have to use OpenWrt
> which dose not support oFono and ConnMan I have to build myself.
>
> Running shell script or python script is not big deal, but to set up
> low modem driver to oFono and ConnMan may take time to learn. I am
> taking your kind and warm advice.
Jupiter,
Your resources of 125 MiB of flash and 250 MiB of RAM are quite generous.
The Nest Learning Thermostat has been an adopter of connman since connman was at roughly 0.7 <https://s3.amazonaws.com/opensource.nest.com/NestLearningThermostat/1.0/c... <https://s3.amazonaws.com/opensource.nest.com/NestLearningThermostat/1.0/c...>>.
The thermostat today continues to use connman, now at 1.29 <https://s3.amazonaws.com/opensource.nest.com/NestLearningThermostat/5.7/c... <https://s3.amazonaws.com/opensource.nest.com/NestLearningThermostat/5.7/c...>> and has similar, roughly half, the resources of your device.
Best,
Grant
3 years, 5 months
The role of connection manager
by JH
Hi,
Does ConnMan provide C API to setup WiFi and LTE connection? Or it is
not necessary to use API but use configuration in main.conf?
I am currently debating with my colleague about if it is necessary to
use connection manager in a small embedded Linux device with network
interfaces of LTE, WiFi and BLE. To cut the long story short, I
strongly proposed to use ConnMan and my colleague is against it, his
argument was connection manager should only be used in desktop not for
embedded system, he wanted to set up WiFi directly from
wpa_supplicant, run LTE connection directly from modem gpio. From my
point of view, set up WiFi directly from wpa_supplicant is fine, but
switch on / off LTE directly from gpio could cause serious
consequences, the application should never interact LTE directly
through low level of GPIO, it'll likely to break the integrity of the
kernel and Linux system where other parts of the kernel or system
access the modem via ioctl communication. The manager will make the
final call. As an embedded developer, none of us have experience in
connection manager, appreciate your comments.
Thank you.
JH
3 years, 5 months