[PATCH] bluez5-device: lower sink/source priority for Audio gateway or a2dp source

[georg@xxxxxxxx (Georg Chini)]

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 sink and source
if PulseAudio is in the headset role. The priority is also lowered if the
device is an a2dp source. In both cases it does not make sense to make the
source or sink default unless there is no other sound device available.
---
 src/modules/bluetooth/module-bluez5-device.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/src/modules/bluetooth/module-bluez5-device.c b/src/modules/bluetooth/module-bluez5-device.c
index 12a49848..c0e681b1 100644
--- a/src/modules/bluetooth/module-bluez5-device.c
+++ b/src/modules/bluetooth/module-bluez5-device.c
@@ -1607,6 +1607,12 @@ static int start_thread(struct userdata *u) {
     if (u->sink) {
         pa_sink_set_asyncmsgq(u->sink, u->thread_mq.inq);
         pa_sink_set_rtpoll(u->sink, u->rtpoll);
+
+        /* If we are in the headset role, the sink should not become default
+         * unless there is no other sound device available. */
+        if (u->profile == PA_BLUETOOTH_PROFILE_HEADSET_AUDIO_GATEWAY)
+            u->sink->priority = 1500;
+
         pa_sink_put(u->sink);
 
         if (u->sink->set_volume)
@@ -1616,6 +1622,13 @@ static int start_thread(struct userdata *u) {
     if (u->source) {
         pa_source_set_asyncmsgq(u->source, u->thread_mq.inq);
         pa_source_set_rtpoll(u->source, u->rtpoll);
+
+        /* If we are in the headset role or the device is an a2dp source,
+         * the source should not become default unless there is no other
+         * sound device available. */
+        if (u->profile == PA_BLUETOOTH_PROFILE_HEADSET_AUDIO_GATEWAY || u->profile == PA_BLUETOOTH_PROFILE_A2DP_SOURCE)
+            u->source->priority = 1500;
+
         pa_source_put(u->source);
 
         if (u->source->set_volume)
-- 
2.11.0