No audio feedback when call is put on hold

[Alfonso Sanchez-Beato]

When a call is put on hold, some operators do not generate tones as expected by the user. We should find out if there is a way to detect this and generate tones in that case.

CLARIFICATION: The issue appears when the other party puts the call on hold. The party affected by the bug is an Ubuntu phone with RemoteHeld property set to 1 when executing list-calls script.

[Jonathan Cave (jocave)]

Found that giffgaff in the UK does not produce a tone.

[Tony Espy (awe)]

Confirmed this behavior on mako running image #u138 with both AT&T (mcc/mnc: 310/410) and T-Mobile ( mcc/mnc: 310/260 ). Neither operator triggers a sound when a call is put on hold/resumed.

Note, the UI toggles it's control correctly ( pause->play->pause... ), and there's haptic feedback from the button press.

[Tony Espy (awe)]

@jocave

I didn't see giffgaff in apns-conf.xml. Does your phone have a working mobile network connection?

[Martti Piirainen (piiramar)]

Two cases:
1. I put a call on hold myself. As Tony writes in comment #2, the dialer UI toggles the button icon and gives haptic feedback. I don't think any additional sounds are necessary here.

2. The far end puts my call on hold. The operator may play a "you are on hold" audio message, or it may send a "supplementary service related network initiated notification" (see 3GPP TS 27.007 "AT command set for User Equipment", section 7.17 "Supplementary service notification"), or neither.

The lower layers of our telephony stack already listen to those notifications (signal RIL_UNSOL_SUPP_SVC_NOTIFICATION in the RIL API, property org.ofono.VoiceCall.RemoteHeld in the oFono API), but we should indicate this also to the user (visually/haptically/audibly). There is also a very similar case "your call has been added to a conference call".

At least in my initial tests in Sonera/Finland network, these notifications are not received. I'll have a closer look.

[Tony Espy (awe)]

@Alfonso

Can you clarify the original bug description? Is the call hold happening locally as in (1) or remotely as in (2), or both?

I re-tested scenario (2) with my AT&T SIM and there's no tone generated, nor does the UI reflect the fact that the call has been put on hold. That said, a quick test on Android shows that it doesn't support any kind of UI notification when a call has been placed on hold, the call timer continues to run and there's no other visual indication. I do hear a tiny change in the audio on the Android phone, but it's not really a tone, it's more the fact that the audio has been cut off, so it goes from white noise to silence.

If the RIL notifications aren't received, there's not much we can do. If they are received, we should confirm whether or not this results in any kind of notification via DBus that could be listened to by the dialer-app. If such mechanism exists, we should add a task for the dialer-app.

[Martti Piirainen (piiramar)]

I re-tested this case
 - dial voice call
 - the far end puts you on hold
and I can now see the RIL notifications in the log
  Jul 23 12:28:52 ubuntu-phablet ofonod[1206]: [UNSOL]< UNSOL_SUPP_SVC_NOTIFICATION {1,2,0,0,(null)}
  Jul 23 12:29:17 ubuntu-phablet ofonod[1206]: [UNSOL]< UNSOL_SUPP_SVC_NOTIFICATION {1,3,0,0,(null)}
and the oFono D-Bus signals being sent
  {VoiceCall} [/ril_0/voicecall01] RemoteHeld = True
  {VoiceCall} [/ril_0/voicecall01] RemoteHeld = False

This is supported up to the oFono API, but not above that. Adding telepathy-ofono, telephony-service, dialer-app as affected. Closing for oFono.