Hey! > Earlier this year, I contributed a feature to detect (e)SIM profile > switches on Quectel modems (commit d98597e43). > > In our use case, we'd like to extend profile switch detection to a > larger selection of modems. In practice, this means detecting when a > REFRESH proactive command is invoked by the SIM card (as specified in > SGP.22). As far as I know, there's no generic way to do this (things > like ICCID polling would probably be too intrusive). But QMI should have > the required functionality, so at least this could be extended to > support QMI based modems that implement the required messages. > > QMI has QMI_UIM_REFRESH_REGISTER/QMI_UIM_REFRESH_REGISTER_ALL messages > that can be used for subscribing events whenever a file on SIM needs > to be refreshed, after which the subscriber receives QMI_UIM_REFRESH_IND > when a file is changed. If this is applied e.g. to the EF containing > ICCID, profile switches should be reliably detectable. > > So, basically, I suppose the following changes in MM/libqmi would be > needed to support this: > - libqmi: Support for the needed QMI_UIM messages. > - MM: On QMI based modems, attempt to register refresh events on init. > - MM: When a refresh event is received, trigger the SIM hot-swap logic > to cause complete refresh of the SIM state in MM. > > I haven't yet tested this in practice (even at PoC level), but before > starting to work on this feature, I'd like to hear comments: does this > sound feasible and if things work well in practice, would the feature be > welcome to be merged to MM? > > The underlying motivation here is that eSIM cards are increasingly being > used in IoT applications and as Linux is an important IoT SW platform, > we'd like them to work as smoothly as possible there. There remains > other work to be done, but getting profile switches to work as fluently > as possible would be a good starting point. >
This all looks good to me, an eSIM profile switch should be to MM's eyes like a SIM hotswap or a SIM slot change. If you're planning to work on this please base your work on top of the following MR, which introduces multi-SIM support for QMI devices (so that you don't get too many conflicts if this MR gets in before you finish): https://gitlab.freedesktop.org/mobile-broadband/ModemManager/-/merge_requests/330 -- Aleksander https://aleksander.es _______________________________________________ ModemManager-devel mailing list ModemManager-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/modemmanager-devel
