[pulseaudio-discuss] issue with audio over headset_head_unit

[James Bottomley]

On Thu, 2016-08-25 at 16:35 +0530, Arun Raghavan wrote:
> On Thu, 25 Aug 2016, at 03:10 PM, Anand Nekkunti wrote:
> > Hi
> >     I am working audio over Bluetooth . I am able to pair and
> > connect
> >     with
> > all speakers(a2dp and HSD ).
> > but audio coming only  speakers which supports a2dp protocol . I am
> > not
> > able to understand why speakers which has HSD protocol not
> > working(no
> > error
> > in pulseaudio log) . Do I need configure anything for this or is
> > there
> > any
> > way forcefully set protocol as a2dp
> > 
> > Board :ARM imx6
> > pulseaudio : 6.0
> > Bluez :5
> > 
> > Working Speaker :
> > 
> >  index: 2
> > name: <bluez_sink.00_9E_C8_11_69_42>
> > driver: <module-bluez5-device.c>
> > flags: HARDWARE DECIBEL_VOLUME LATENCY
> > state: IDLE
> > suspend cause:
> > priority: 9030
> > volume: front-left: 65536 / 100% / 0.00 dB,   front-right: 65536 /
> > 100% /
> > 0.00 dB
> >        balance 0.00
> > base volume: 65536 / 100% / 0.00 dB
> > volume steps: 65537
> > muted: no
> > current latency: 28.67 ms
> > max request: 3 KiB
> > max rewind: 0 KiB
> > monitor source: 4
> > sample spec: s16le 2ch 44100Hz
> > channel map: front-left,front-right
> >             Stereo
> > used by: 0
> > linked by: 0
> > fixed latency: 42.41 ms
> > card: 2 <bluez_card.00_9E_C8_11_69_42>
> > module: 21
> > properties:
> > bluetooth.protocol = "a2dp_sink"
> > device.description = "Mi Bluetooth Speaker"
> > device.string = "00:9E:C8:11:69:42"
> > device.api = "bluez"
> > device.class = "sound"
> > device.bus = "bluetooth"
> > device.form_factor = "portable"
> > bluez.path = "/org/bluez/hci0/dev_00_9E_C8_11_69_42"
> > bluez.class = "0x24041c"
> > bluez.alias = "Mi Bluetooth Speaker "
> > device.icon_name = "multimedia-player-bluetooth"
> > ports:
> > portable-output: Portable (priority 0, latency offset 0 usec,
> > available:
> > yes)
> > properties:
> > active port: <portable-output>
> > 
> > 
> > 
> > Not Working Speaker:
> >    index: 2
> > name: <bluez_sink.00_0C_8A_67_14_4E>
> > driver: <module-bluez5-device.c>
> > flags: HARDWARE HW_VOLUME_CTRL LATENCY
> > state: RUNNING
> > suspend cause:
> > priority: 9030
> > volume: mono: 43691 /  67%
> >        balance 0.00
> > base volume: 65536 / 100%
> > volume steps: 16
> > muted: no
> > current latency: 31.00 ms
> > max request: 0 KiB
> > max rewind: 0 KiB
> > monitor source: 4
> > sample spec: s16le 1ch 8000Hz
> > channel map: mono
> >             Mono
> > used by: 1
> > linked by: 1
> > fixed latency: 128.00 ms
> > card: 2 <bluez_card.00_0C_8A_67_14_4E>
> > module: 21
> > properties:
> > bluetooth.protocol = "headset_head_unit"
> > device.intended_roles = "phone"
> > device.description = "Bose AE2w 01.01.00"
> > device.string = "00:0C:8A:67:14:4E"
> > device.api = "bluez"
> > device.class = "sound"
> > device.bus = "bluetooth"
> > device.form_factor = "headset"
> > bluez.path = "/org/bluez/hci0/dev_00_0C_8A_67_14_4E"
> > bluez.class = "0x240404"
> > bluez.alias = "Bose AE2w 01.01.00"
> > device.icon_name = "audio-headset-bluetooth"
> > ports:
> > headset-output: Headset (priority 0, latency offset 0 usec,
> > available:
> > unknown)
> > properties:
> > active port: <headset-output>
> 
> Are you using the native backend (HSP) or oFono (HFP) here? Might 
> help to look at system logs, or get verbose output from PulseAudio 
> and BlueZ.

There seems to be a misunderstanding here (I just went around the block
with Marcel on it).  The fact is that the backend-ofono can only talk
to a phone, where it emulates HFP, it can't talk to an actual headset. 
 Meaning that if you have a headset trying to talk to your computer,
you are ipso facto using the native backend.

The confusion seems to be because at one time there were patches to
backend-ofono to talk to headsets, but they depended on non-upstream
bluez parts and they were never merged.

James