[pulseaudio-discuss] Bluetooth + HSP + Raspberry?

[Bram de Jong]

Hi Tanu,

> The text that you quoted refers to the functionality provided by
> module-bluetooth-policy. That module loads module-loopback automatically
> when a bluetooth source (a2dp or hfgw) appears. I think PA2 supports the
> hfgw profile, it just doesn't load module-loopback automatically. You
> didn't say what you want to do with the audio from the phone, so I don't
> know if you even need module-loopback, but if you do, you can load it
> manually just fine.

What I want to do is use the Raspberry as a speaker only using the
low-latency HSP (which you cann HFGW) bluetooth profile. This should
mainly be for making calls from another computer.

[Computer with e.g. skype]----> [raspberry]---->amp/speaker

Where the sound input (i.e. microphone) will be the computer's microphone.

> If you have already successfully streamed audio from your phone to the
> pi using a2dp, then you have already used the pi as a fake headset. The
> only difference with HSP is that instead of the a2dp_source profile, you
> need to set the bluetooth card in pulseaudio to use the hfgw profile.

Would that be:

pacmd set-card-profile <cardid> hfgw

This seems to fail:

$ pactl set-card-profile 3 hfgw
Failure: Input/Output error

The same with pacmd reports: Failed to set card profile to 'hfgw'.
(I'm still confused as when to use which)

Syslog:
[pulseaudio] module-bluetooth-device.c: HandsfreeGateway is not
connected, refused to switch profile


Even though the card seems to have the right specification:

Card #4
    Name: bluez_card.38_0A_94_A3_EE_59
    Driver: module-bluetooth-device.c
    Owner Module: 30
    Properties:
        device.description = "Galaxy Nexus 2"
        device.string = "38:0A:94:A3:EE:59"
        device.api = "bluez"
        device.class = "sound"
        device.bus = "bluetooth"
        bluez.path = "/org/bluez/2118/hci0/dev_38_0A_94_A3_EE_59"
        bluez.class = "0x5a020c"
        bluez.name = "Galaxy Nexus 2"
        device.icon_name = "audio-card-bluetooth"
    Profiles:
        a2dp_source: High Fidelity Capture (A2DP) (sinks: 0, sources:
1, priority. 10)
        hfgw: Handsfree Gateway (sinks: 1, sources: 1, priority. 20)
        off: Off (sinks: 0, sources: 0, priority. 0)
    Active Profile: a2dp_source

I tried it while on the phone and just playing music.
I tried the same with my laptop and it failed with the same reasons.

-> Is there some kind of way to always load bluetooth as HSP/HFGW?

> That shouldn't be necessary. And if you do upgrade, you definitely
> shouldn't upgrade bluez to any of the 5.x versions, because pulseaudio
> doesn't yet work with them.

Ah, thanks for that warning!


 - bram

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