Aleksander Morgado
16e3bb892d
If the modem is connected and we receive indications of a quick
unregistration cycle (i.e. unregistered, then registered again) we
should not end up flagging the modem as disconnected.
We already had some logic to avoid this with the "deferred 3GPP
unregistration" logic in the base bearer object, but this logic only
took into account the status of the bearer, not the status of the
modem.
Wed Jul 29 15:35:44 2020 daemon.info [1567]: <info> Modem /org/freedesktop/ModemManager1/Modem/0: 3GPP Registration state changed (home -> idle)
Wed Jul 29 15:35:44 2020 daemon.debug [1567]: <debug> Modem /org/freedesktop/ModemManager1/Modem/0: 3GPP location updated (MCC: '0', MNC: '0', Location area code: '0', Tracking area code: '1CE8', Cell ID: '68F832')
Wed Jul 29 15:35:44 2020 daemon.debug [1567]: <debug> Connected bearer not registered in 3GPP network
Wed Jul 29 15:35:44 2020 daemon.info [1567]: <info> Modem /org/freedesktop/ModemManager1/Modem/0: state changed (connected -> enabled)
Wed Jul 29 15:35:44 2020 daemon.debug [1567]: <debug> Modem /org/freedesktop/ModemManager1/Modem/0: signal quality updated (0)
Wed Jul 29 15:35:44 2020 daemon.debug [1567]: <debug> Modem /org/freedesktop/ModemManager1/Modem/0: access technology changed (lte -> unknown)
Wed Jul 29 15:35:44 2020 daemon.debug [1567]: <debug> Periodic signal checks disabled
Wed Jul 29 15:35:44 2020 daemon.info [1567]: <info> Modem /org/freedesktop/ModemManager1/Modem/0: 3GPP Registration state changed (idle -> registering)
Wed Jul 29 15:35:44 2020 daemon.debug [1567]: <debug> Modem /org/freedesktop/ModemManager1/Modem/0: 3GPP location updated (MCC: '0', MNC: '0', Location area code: '0', Tracking area code: '1C84', Cell ID: 'A3E050')
Wed Jul 29 15:35:44 2020 daemon.debug [1567]: <debug> Modem /org/freedesktop/ModemManager1/Modem/0: 3GPP location updated (MCC: '238', MNC: '1', Location area code: '0', Tracking area code: '1C84', Cell ID: 'A3E050')
Wed Jul 29 15:35:44 2020 daemon.info [1567]: <info> Modem /org/freedesktop/ModemManager1/Modem/0: 3GPP Registration state changed (registering -> home)
Wed Jul 29 15:35:44 2020 daemon.info [1567]: <info> Modem /org/freedesktop/ModemManager1/Modem/0: state changed (enabled -> registered)
We now try to improve this situation by also considering the case
where modem is supposed to get into "enabled" state (i.e. not
registered, not searching), but we still consider the amount of
connected bearers to decide the final state reported by the modem. In
other words, a modem with the 3GPP registration reported as 'idle'
will still be reported as 'connected' if there is at least one bearer
in connected state. This situation will end as soon as the 'deferred
3GPP unregistration' timeout expires, as that will force the bearer to
be disconnected.
ModemManager. ModemManager provides a unified high level API for communicating with mobile broadband modems, regardless of the protocol used to communicate with the actual device (Generic AT, vendor-specific AT, QCDM, QMI, MBIM...). Using. ModemManager is a system daemon and is not meant to be used directly from the command line. However, since it provides a DBus API, it is possible to use 'dbus-send' commands or the new 'mmcli' command line interface to control it from the terminal. The devices are queried from udev and automatically updated based on hardware events, although a manual re-scan can also be requested to look for RS232 modems. Implementation. ModemManager is a DBus system bus activated service (meaning it's started automatically when a request arrives). It is written in C, using glib and gio. Several GInterfaces specify different features that the modems support, including the generic MMIfaceModem3gpp and MMIfaceModemCdma which provide basic operations for 3GPP (GSM, UMTS, LTE) or CDMA (CDMA1x, EV-DO) modems. If a given feature is not available in the modem, the specific interface will not be exported in DBus. Plugins. Plugins are loaded on startup, and must implement the MMPlugin interface. It consists of a couple of methods which tell the daemon whether the plugin supports a port and to create custom MMBroadbandModem implementations. It most likely makes sense to derive custom modem implementations from one of the generic classes and just add (or override) operations which are not standard. There are multiple fully working plugins in the plugins/ directory that can be used as an example for writing new plugins. Writing new plugins is highly encouraged! The plugin API is open for changes, so if you're writing a plugin and need to add or change some public method, feel free to suggest it! License. The ModemManager and mmcli binaries are both GPLv2+. The libmm-glib library is LGPLv2+.