[pulseaudio-discuss] [PATCH] sink/source: lower priority of phone sinks/sources

[Georg Chini]

On 02.09.2017 13:12, Tanu Kaskinen wrote:
> On Fri, 2017-09-01 at 16:21 +0200, Georg Chini wrote:
>> When a phone is connected via bluetooth and switches to HFP, the sinks
>> and sources will have higher priority than the built-in devices.
>> Therefore they are chosen as default and module-bluetooth-policy will
>> incorrectly insert loopback modules that loop the phone back to itself.
>>
>> This patch fixes the problem by lowering the priority of devices with
>> the form factor "phone" so that they are never chosen as default sink
>> or source unless no other sound device is available.
>> ---
>>   src/pulsecore/sink.c | 2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/src/pulsecore/sink.c b/src/pulsecore/sink.c
>> index a8b4cd3d..e1bd5a08 100644
>> --- a/src/pulsecore/sink.c
>> +++ b/src/pulsecore/sink.c
>> @@ -3529,6 +3529,8 @@ unsigned pa_device_init_priority(pa_proplist *p) {
>>               priority += 450;
>>           else if (pa_streq(s, "internal"))
>>               priority += 400;
>> +        else if (pa_streq(s, "phone"))
>> +            priority -= 1000;
>>       }
>>   
>>       if ((s = pa_proplist_gets(p, PA_PROP_DEVICE_BUS))) {
> priority is unsigned, and its value is not guaranteed to be high enough
> for substracting 1000 from it.
>
> Maybe it would make sense to just immediately return 0 if we spot a
> phone form factor?
>
I think the priority should still be higher than a null-sink, so it
would be OK to return something like 1500.

There is also another way to achieve the same thing. We could
set the priorities in the bluetooth code when the sink/source are
put and pulseaudio is in the headset role or the device is an a2dp
source. That would be more general than only checking the form
factor.

What do you think?