Hi Slava,

On 09/10/2018 02:56 PM, Slava Monich wrote:
> Hi Denis,
>> Hi Slava,
>>
>> On 09/10/2018 01:26 PM, Slava Monich wrote:
>>> Hi Anirudh, Denis at al.
>>>
>>>> @@ -669,6 +669,10 @@ const char *registration_status_to_string(int 
>>>> status)
>>>>>           return "unknown";
>>>>>       case NETWORK_REGISTRATION_STATUS_ROAMING:
>>>>>           return "roaming";
>>>>> +    case NETWORK_REGISTRATION_STATUS_REGISTERED_EUTRAN:
>>>>> +        return "registered lte";
>>>>> +    case NETWORK_REGISTRATION_STATUS_ROAMING_EUTRAN:
>>>>> +        return "roaming lte";
>>>
>>> What would be the difference between "roaming lte" and "roaming" (or 
>>> "registered lte" vs "registered") from the viewpoint of D-Bus API 
>>> clients? In other words, what would e.g. dialer do differently 
>>> depending on whether registration status is "registered lte" or just 
>>> "registered"? Is it worth the API break? The existing clients won't 
>>> know how to handle the new values until they (clients) get updated.
>>>
>>
>> I agree.  That is why I suggested a separate Property for this (and 
>> the CSFB case from 27.007) instead of modifying the Status property 
>> directly.
>>
>> E.g. REGISTERED_SMS_EUTRAN would map to Status="registered" and 
>> SmsOnly=False.  ROAMING_SMS_EUTRAN would map to Status="roaming" and 
>> SmsOnly=True.
>>
>> I assume that the Dialer can ignore this as the modem will fall back 
>> to 3G in case of a call?  Someone feel free to educate me.
> 
> The modems I dealt with do drop to 3G for voice calls. Once voice call 
> terminates, they switch back to LTE (well, most of the time). Dialler 
> (at least our dialler) doesn't care about access technology.

That is what I've seen as well.  But these are pre-VoLTE devices most 
likely.  VoLTE might act differently.

> 
> Just a thought - could the presence of org.ofono.VoiceCallManager and 
> org.ofono.MessageManager interfaces be used to indicate whether voice 
> calls and/or messaging is available? That wouldn't require any D-Bus API 
> changes at all.
> 

VoiceCallManager should always be available since you still need to make 
Emergency Calls.  There might be some really weird legacy devices which 
were Data-Only, but those aren't really the focus of oFono anyway.

What I assume is happening in 27.007 is that registration states 6/9 & 
7/10 allows one to discern whether Circuit Switched Fallback would be 
triggered.  I assume if the device (& network) is VoLTE capable, then 
you'd see state 9/10, 6/7 otherwise.  Perhaps all 4 states should be 
combined into a single CircuitSwitchedFallback property instead...

Regards,
-Denis