Mic mute does not work on Nexus4

[Alan Pope 🍺🐧🐱 🦄]

Saucy 8 image on Mako (nexus 4). (had same problem on raring)

make a phone call
press the Speaker or microphone button to enable speakerphone or mute mic
Neither button works.

expect speaker button to enable speakerphone and mic button to mute microphone.

[Omer Akram (om26er)]

The speaker phone does work now. Its the mute button that does not. Also the 'pause/hold' button does not work either, from what I know that getting implemented this cycle so better remove that button from the UI

[Bill Filler (bfiller)]

mic mute works for me on Galaxy Nexus using Sep 16 build. Can someone try it on Galaxy Nexus to confirm?

[Dave Morley (davmor2)]

On image 54 this is working for me on Maguro.

The Mute button knocks the mic off and when re-enabled makes it work again. The Speaker button works as expected too.

[Bill Filler (bfiller)]

This is a Nexus 4 specific bug. Works as expected on Maguro.

[Tony Espy (awe)]

I mentioned last week that there was a fix in the nemomobile call-volume code which fixed the parsing of the GET_MUTE response, and that I was hopeful that this would fix the problem. It doesn't...

I've run RIL traces on both phones, and I see the exact same sequence of requests sent.

On startup, the mute state is probed, and on both, it's enabled. When an outgoing call is made, REQUEST_SET_MUTE (0) is sent to RIL on both phones to disable mute at the start of a call. When the mute button is pressed, I see REQUEST_SET_MUTE (1) sent for both, with a normal response returned.

So for some reason, the Nexus4 RILD is ignoring the mute request.

The next step to debug is to flash vanilla Cyanogenmod and enable RILC tracing.

[Tony Espy (awe)]

I flashed vanilla Cyanogenmod 10.1 on my mako, and the mute function works as expected. Time to poke through some RIL IPC traces next.

[Tony Espy (awe)]

I also flashed CM 10.1 on maguro, and ran the same scenario. It looks to me like mako isn't using REQUEST_SET_MUTE to enable mute when the button is pressed, whereas maguro does send a REQUEST_SET_MUTE with the value "1" to enable the call mute.

I'll spend some time looking at the Android/CM code and see if I can determine whether not mako is using an alternative mechanism...

[Tony Espy (awe)]

Suspicion confirmed, mako routes mic mute requests directly to the AudioManager, whereas maguro relies on RILD to mute the mic.

The code in question is ( see line 2020 ):

http://androidxref.com/source/xref/packages/apps/Phone/src/com/android/phone/PhoneUtils.java

Also, if you do a search for the symbol 'send_mic_mute_to_AudioManager', you'll find an overlay resource file for mako, which sets this value in the phone app:

http://androidxref.com/source/xref/device/lge/mako/overlay/packages/apps/Phone/res/values/config.xml

So... to fix this bug, we'll need assistance from David Henningsson.

[Tony Espy (awe)]

Due to the analysis posted in comment #8, I just marked the ofono ( Ubuntu ) task as Invalid.

[David Henningsson (diwic)]

I wrote the PulseAudio backend for setting mic mute and call volume from telepathy-ofono a while ago. The code is available for review here:

https://code.launchpad.net/~diwic/telepathy-ofono/micmute

However I believe tiago needs to connect this to the ordinary mic mute path too.