Notify requests are requests sent by ISA servers towards clients. They
are identical to indications in that no response is necessary, but
different in that subscription is done not using the mechanism used
for indications, but out-of-band. Typically routing for notify
requests is enabled using a request-response pair.
Implementing all the voicecall methods. Tested with Nokia 2008 modems.
- problems in call creation are probably not reported properly
- deflect not implemented in modem, not properly tested
TODO: Clean up style issues and align with other drivers.
This patch adds an API for querying the ISI version of the resource
with which the client is associated. This information is only
available after g_isi_verify() has been called on the client. This is
because we use the version query message as a vehicle for reachability
checking.