When the data connection is started with AT^SWWAN, the modem expects
the DHCP discover packet from the TE while the command is running,
i.e. while the modem has not replied yet. In order to achieve that,
the bearer is marked as connected as soon as the command is
issued. This makes the NetworkManager start the DHCP process.
If the modem replies with an error, the bearer will be marked
disconnected later on.
See https://gitlab.freedesktop.org/mobile-broadband/ModemManager/-/merge_requests/50
for a similar functionality in the ublox driver.
Includes minor coding style fixes from Aleksander Morgado
<aleksandermj@chromium.org>.
Signed-off-by: Christian Taedcke <christian.taedcke@lemonbeat.com>
The previously used COPS command to set to LTE-only mode did not work
for an ELS81 modem.
Now ^SXRAT is used to switch modes instead of COPS, if SXRAT is
supported by the modem.
Christian Taedcke