[Matter] Bluetooth: settings_load is only called if CONFIG_BT_BONDABLE is set

[rlmediola]

I'm not sure if this is the right place for this question.

I'm using the Settings subsystem for the BLE name.

When BLE is initialized inside matter, settings_load is only called if CONFIG_BT_BONDABLE is set (modules/lib/matter/src/platform/Zephyr/BLEManagerImpl.cpp). This leads to the error "Can't register service after init and before settings are loaded." when matter tries to register the GATT service.

I can fix this by calling settings_load before initializing matter, but this results in the BLE name being an empty string. The problem here is that BLE settings are only loaded when calling settings_load after bt_enable.

Therefore I have to post a task to matter that calls settings_load_subtree("bt")) and restarts the advertising. Then everything works as expected.

Is this a bug or am I missing something here?

[Vidar Berg]

Hi,

It looks like we have made the assumption that BT_SETTINGS will only be used together with CONFIG_BT_BONDABLE. So I understand this correctly, if you enable CONFIG_BT_BONDABLE it works as well? I have forwarded this question internally. 

Best regards,

Vidar

[rlmediola]

Yes, I don't know why CONFIG_BT_BONDABLE is required.

I enabled CONFIG_BT_SMP and CONFIG_BT_BONDABLE but it failed at bt_id_create (github).

I had to add CONFIG_BT_ID_MAX=2 as well in our project to trigger the bt_id_reset call afterwards and then it was working.

[Vidar Berg]

Sorry for the delay. I've been waiting to discuss the issue with the author of the commit, but he's been out of the office all week. I don't foresee any problems with the workaround you described in your first post. I also think you can patch init function in BLEManagerImpl.cpp like below. 

...

#else

err = InitRandomStaticAddress(false, id);

VerifyOrReturnError(err == 0 && id == kMatterBleIdentity, MapErrorZephyr(err));

err = bt_enable(nullptr);

if (IS_ENABLED(CONFIG_BT_SETTINGS)) {

settings_load();

}

VerifyOrReturnError(err == 0, MapErrorZephyr(err));

#endif // CONFIG_BT_BONDABLE

...