[Qemu-devel] [PULL 21/26] paaudio: channel-map option

[Gerd Hoffmann <kraxel@redhat.com>]

From: Kővágó, Zoltán <dirty.ice.hu@gmail.com>

Add an option to change the channel map used by pulseaudio.  If not
specified, falls back to an OSS compatible channel map.

Signed-off-by: Kővágó, Zoltán <DirtY.iCE.hu@gmail.com>
Message-id: 66670d43bd932be0919668cec6a8cd172bfb8383.1568574965.git.DirtY.iCE.hu@gmail.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 audio/paaudio.c | 18 ++++++++++++++----
 qapi/audio.json |  7 +++++--
 qemu-options.hx |  9 +++++++++
 3 files changed, 28 insertions(+), 6 deletions(-)

diff --git a/audio/paaudio.c b/audio/paaudio.c
index d195b1caa8d8..20402b071804 100644
--- a/audio/paaudio.c
+++ b/audio/paaudio.c
@@ -338,17 +338,27 @@ static pa_stream *qpa_simple_new (
         pa_stream_direction_t dir,
         const char *dev,
         const pa_sample_spec *ss,
-        const pa_channel_map *map,
+        const char *map,
         const pa_buffer_attr *attr,
         int *rerror)
 {
     int r;
     pa_stream *stream;
     pa_stream_flags_t flags;
+    pa_channel_map pa_map;
 
     pa_threaded_mainloop_lock(c->mainloop);
 
-    stream = pa_stream_new(c->context, name, ss, map);
+    if (map && !pa_channel_map_parse(&pa_map, map)) {
+        dolog("Invalid channel map specified: '%s'\n", map);
+        map = NULL;
+    }
+    if (!map) {
+        pa_channel_map_init_extend(&pa_map, ss->channels,
+                                   PA_CHANNEL_MAP_OSS);
+    }
+
+    stream = pa_stream_new(c->context, name, ss, &pa_map);
     if (!stream) {
         goto fail;
     }
@@ -421,7 +431,7 @@ static int qpa_init_out(HWVoiceOut *hw, struct audsettings *as,
         PA_STREAM_PLAYBACK,
         ppdo->has_name ? ppdo->name : NULL,
         &ss,
-        NULL,                   /* channel map */
+        ppdo->has_channel_map ? ppdo->channel_map : NULL,
         &ba,                    /* buffering attributes */
         &error
         );
@@ -470,7 +480,7 @@ static int qpa_init_in(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque)
         PA_STREAM_RECORD,
         ppdo->has_name ? ppdo->name : NULL,
         &ss,
-        NULL,                   /* channel map */
+        ppdo->has_channel_map ? ppdo->channel_map : NULL,
         &ba,                    /* buffering attributes */
         &error
         );
diff --git a/qapi/audio.json b/qapi/audio.json
index 0535eff7948f..07003808cba7 100644
--- a/qapi/audio.json
+++ b/qapi/audio.json
@@ -214,13 +214,16 @@
 # @latency: latency you want PulseAudio to achieve in microseconds
 #           (default 15000)
 #
+# @channel-map: channel map to use (default: OSS compatible map, since: 4.2)
+#
 # Since: 4.0
 ##
 { 'struct': 'AudiodevPaPerDirectionOptions',
   'base': 'AudiodevPerDirectionOptions',
   'data': {
-    '*name': 'str',
-    '*latency': 'uint32' } }
+    '*name':        'str',
+    '*latency':     'uint32',
+    '*channel-map': 'str' } }
 
 ##
 # @AudiodevPaOptions:
diff --git a/qemu-options.hx b/qemu-options.hx
index 734a3b5d6569..6aee778896b8 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -471,6 +471,7 @@ DEF("audiodev", HAS_ARG, QEMU_OPTION_audiodev,
     "-audiodev pa,id=id[,prop[=value][,...]]\n"
     "                server= PulseAudio server address\n"
     "                in|out.name= source/sink device name\n"
+    "                in|out.channel-map= channel map to use\n"
 #endif
 #ifdef CONFIG_AUDIO_SDL
     "-audiodev sdl,id=id[,prop[=value][,...]]\n"
@@ -636,6 +637,14 @@ Sets the PulseAudio @var{server} to connect to.
 @item in|out.name=@var{sink}
 Use the specified source/sink for recording/playback.
 
+@item in|out.channel-map=@var{map}
+Use the specified channel map.  The default is an OSS compatible
+channel map.  Do not forget to escape commas inside the map:
+
+@example
+-audiodev pa,id=example,sink.channel-map=front-left,,front-right
+@end example
+
 @end table
 
 @item -audiodev sdl,id=@var{id}[,@var{prop}[=@var{value}][,...]]
-- 
2.18.1