audio: paaudio: ability to specify stream name

This can be used to identify stream in tools like pavucontrol when one
creates multiple -audiodevs or runs multiple qemu instances.

Signed-off-by: Kővágó, Zoltán <DirtY.iCE.hu@gmail.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-id: 2d6e337c474ac84172d0809e6959c26b21d48120.1568157545.git.DirtY.iCE.hu@gmail.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

audio/paaudio.c

@@ -339,7 +339,7 @@ static int qpa_init_out(HWVoiceOut *hw, struct audsettings *as,
 
     pa->stream = qpa_simple_new (
         c,
-        g->dev->id,
+        ppdo->has_stream_name ? ppdo->stream_name : g->dev->id,
         PA_STREAM_PLAYBACK,
         ppdo->has_name ? ppdo->name : NULL,
         &ss,
@@ -388,7 +388,7 @@ static int qpa_init_in(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque)
 
     pa->stream = qpa_simple_new (
         c,
-        g->dev->id,
+        ppdo->has_stream_name ? ppdo->stream_name : g->dev->id,
         PA_STREAM_RECORD,
         ppdo->has_name ? ppdo->name : NULL,
         &ss,

qapi/audio.json

@@ -206,6 +206,11 @@
 #
 # @name: name of the sink/source to use
 #
+# @stream-name: name of the PulseAudio stream created by qemu.  Can be
+#               used to identify the stream in PulseAudio when you
+#               create multiple PulseAudio devices or run multiple qemu
+#               instances (default: audiodev's id, since 4.2)
+#
 # @latency: latency you want PulseAudio to achieve in microseconds
 #           (default 15000)
 #
@@ -215,6 +220,7 @@
   'base': 'AudiodevPerDirectionOptions',
   'data': {
     '*name': 'str',
+    '*stream-name': 'str',
     '*latency': 'uint32' } }
 
 ##