Hey! > > > > > I need to collect informations about modems (for IMEI) and SIM cards > > > > > (for IMSI) available to system over D-Bus. > > > > > > > > > > While listening to signal InterfacesAdded on interface > > > > > org.freedesktop.DBus.ObjectManager does work as mentioned in > > > > > documentation, ie. returning properties on newly discovered modem, > > > > > I cannot get this work for SIm cards. Here listening to > > > > > PropertiesChanged for both Modem or SIM interface does not > > > > > return anything. Current "solution" is to look at SIM object > > > > > path after while, which gets SIM a chance to be discovered, > > > > > but I would prefer to know how to implement it "the right > > > > > way" (tm). > > > > > > > > > > > > > The "manager" object in ModemManager implements > > > > org.freedesktop.DBus.ObjectManager but ONLY for modem objects. This > > > > means that the ObjectManager interface only notifies about > > > > added/removed interfaces in modem objects. > > > > > > > > Once you have the path for an existing modem object with a > > > > "org.freedesktop.ModemManager1.Modem" interface, you should then > > > > monitor the "Sim" property in that interface, which will give you the > > > > DBus path to the SIM object available in the modem. > > > > > > Well, perhaps I didn't make above clear. I'm waiting for Modem object > > > to appear on the bus, which works reliably. Once it appears I'm hooking > > > "PropertiesChanged" on it which also works as you indicated above. > > > Here "Sim" property is also available and object it points to does not > > > emit changes [*]. So once new modem appears on the bus, its Sim > > > property contains valid path to Sim object, but Imsi property of that > > > object is empty at that time. However, asking again after some time gives > > > expected result. > > > > I'm not sure why you're seeing this. The SIM object creation involves > > loading IMSI/ICCID as part of the creation, and only once all have > > been loaded (or failed to load) then we export the SIM object in DBus, > > with the properties already set. There is no "reloading" after the SIM > > object has already been exposed in DBus. I have never seen this issue > > when using libmm-glib, truth be told, I think you'll have to debug it > > further I'm afraid, or otherwise share a simple tester program that > > reproduces the issue. > > I do not follow. You need to create SIM object to have something to issue > SendPin method on right? So after Sim is unlocked (I guess NetworkManager > sends it as it lives in NetworkManager's config file), IMSI is read and > property updated. Or does it work any other way around? >
Ohhh I know what the issue is :D your question helped. The correct sequence is the following: * The SIM object is created in MM's logic only after all IMSI/ICCID/MCC/MNC are loaded (attempted to be loaded) from the modem. * Once the SIM object is fully created, the object is exported in DBus. * And once it has been exported in DBus, the "sim" property of the "Modem" interface in the modem object is populated with the path of the SIM object in DBus. * And then, applications (e.g. NetworkManager) can call SendPin() or any other method on the SIM object. * After SIM-PIN unlocked, we launch a "reinitialization" of the SIM object properties, so that any property that failed to load due to the SIM-PIN lock can now be reloaded. I believe that last point is what you're seeing. For reference:https://cgit.freedesktop.org/ModemManager/ModemManager/tree/src/mm-iface-modem.c#n4958 You definitely need to monitor PropertiesChanged in the SIM object, as they may be updated during runtime, e.g. when loaded only after SIM-PIN unlocked. > > > > It is "guaranteed" by the implementation that the SIM path does NOT > > > > change in the same modem object, though. If for any reason the SIM is > > > > ejected and changed, the actual modem object will be completely > > > > re-created and the modem object path will also change. > > > > > > A side question: Once ModemManager is restarted all the hooks to > > > "PropertiesChanged" has to be destroyed using "NameOwnerChanged" > > > onInterface "org.freedesktop.DBus" and then created again using > > > "InterfacesAdded" of "org.freedesktop.DBus.ObjectManager" to get > > > internal application state into sync with ModemManger. Is that > > > correct or does some more elegant shortcut exist? > > > > > > > Once ModemManager is restarted, all the objects exposed by the old and > > the new MM processes are completely different, and MM itself has a > > different bus address. So, whenever MM goes away, you need to cleanup > > all the stuff that you were monitoring. The main issue you're having > > here is that you're doing all this low-level stuff yourself, I assume > > because you cannot use libmm-glib or ModemManagerQt, right? > > I'm using sdbus-c++ the best D-Bus library I've ever seen :) > If you're using a low-level library you definitely need to handle all those things yourself I'm afraid, yes. Or write a new client-side MM library using sdbus-c++ :D > > > [*] debug on "PropertiesChanged" of "Modem" gives: > > > Property UnlockRequired at org.freedesktop.ModemManager1.Modem changed > > > Property State at org.freedesktop.ModemManager1.Modem changed > > > Property State at org.freedesktop.ModemManager1.Modem changed > > > Property State at org.freedesktop.ModemManager1.Modem.Modem3gpp.Ussd > > > changed > > > Property Enabled at org.freedesktop.ModemManager1.Modem.Location changed > > > Property State at org.freedesktop.ModemManager1.Modem changed > > > Property State at org.freedesktop.ModemManager1.Modem changed > > > Property RegistrationState at > > > org.freedesktop.ModemManager1.Modem.Modem3gpp changed > > > Property OperatorCode at org.freedesktop.ModemManager1.Modem.Modem3gpp > > > changed > > > Property OperatorName at org.freedesktop.ModemManager1.Modem.Modem3gpp > > > changed > > > Property State at org.freedesktop.ModemManager1.Modem changed > > > Property RegistrationState at > > > org.freedesktop.ModemManager1.Modem.Modem3gpp changed > > > Property Bearers at org.freedesktop.ModemManager1.Modem changed > > > Property State at org.freedesktop.ModemManager1.Modem changed > > > Property SignalQuality at org.freedesktop.ModemManager1.Modem changed > > > Property State at org.freedesktop.ModemManager1.Modem changed > > > > > > As you can see there is no change on org.freedesktop.ModemManager1.Sim > > > which is probably okay, per what you wrote before, but that leaves me > > > with no nice solution. Suggestions? > > > > > > > Wait, you won't see a property update on the > > "org.freedesktop.ModemManager1.Sim" interface by monitoring the > > PropertiesUpdated of the modem object. How about you monitor > > PropertiesUpdated on the SIM object instead? > > Sorry, that handler is hooked to both "org.freedesktop.ModemManager1.Sim" > and "org.freedesktop.ModemManager1.Modem", but only changes from "Modem" > object are seen. Please try hooking it to the SIM object. All objects exposed by MM implement "org.freedesktop.DBus.Properties" (with "PropertiesChanged" signal). -- Aleksander https://aleksander.es _______________________________________________ ModemManager-devel mailing list ModemManager-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/modemmanager-devel
