audio/dbus: use a helper function to set the backend dbus server

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

audio/audio.c

@@ -2223,6 +2223,23 @@ AudioBackend *audio_be_by_name(const char *name, Error **errp)
     }
 }
 
+#ifdef CONFIG_GIO
+bool audio_be_set_dbus_server(AudioBackend *be,
+                              GDBusObjectManagerServer *server,
+                              bool p2p,
+                              Error **errp)
+{
+    assert(be != NULL);
+
+    if (!be->drv->set_dbus_server) {
+        error_setg(errp, "Audiodev '%s' is not compatible with DBus", be->dev->id);
+        return false;
+    }
+
+    return be->drv->set_dbus_server(be, server, p2p, errp);
+}
+#endif
+
 const char *audio_be_get_id(AudioBackend *be)
 {
     if (be) {

audio/audio.h

@@ -28,6 +28,9 @@
 #include "qemu/queue.h"
 #include "qapi/qapi-types-audio.h"
 #include "hw/qdev-properties-system.h"
+#ifdef CONFIG_GIO
+#include "gio/gio.h"
+#endif
 
 typedef void (*audio_callback_fn) (void *opaque, int avail);
 
@@ -162,6 +165,12 @@ void audio_help(void);
 AudioBackend *audio_be_by_name(const char *name, Error **errp);
 AudioBackend *audio_get_default_audio_be(Error **errp);
 const char *audio_be_get_id(AudioBackend *be);
+#ifdef CONFIG_GIO
+bool audio_be_set_dbus_server(AudioBackend *be,
+                              GDBusObjectManagerServer *server,
+                              bool p2p,
+                              Error **errp);
+#endif
 
 #define DEFINE_AUDIO_PROPERTIES(_s, _f)         \
     DEFINE_PROP_AUDIODEV("audiodev", _s, _f)

audio/audio_int.h

@@ -148,7 +148,10 @@ struct audio_driver {
     void *(*init) (Audiodev *, Error **);
     void (*fini) (void *);
 #ifdef CONFIG_GIO
-    void (*set_dbus_server)(AudioBackend *s, GDBusObjectManagerServer *manager, bool p2p);
+    bool (*set_dbus_server)(AudioBackend *be,
+                            GDBusObjectManagerServer *manager,
+                            bool p2p,
+                            Error **errp);
 #endif
     struct audio_pcm_ops *pcm_ops;
     int max_voices_out;

audio/dbusaudio.c

@@ -645,8 +645,11 @@ dbus_audio_register_in_listener(AudioBackend *s,
                                         arg_listener, false);
 }
 
-static void
-dbus_audio_set_server(AudioBackend *s, GDBusObjectManagerServer *server, bool p2p)
+static bool
+dbus_audio_set_server(AudioBackend *s,
+                      GDBusObjectManagerServer *server,
+                      bool p2p,
+                      Error **errp)
 {
     DBusAudio *da = s->drv_opaque;
 
@@ -669,6 +672,8 @@ dbus_audio_set_server(AudioBackend *s, GDBusObjectManagerServer *server, bool p2
     g_dbus_object_skeleton_add_interface(G_DBUS_OBJECT_SKELETON(da->audio),
                                          G_DBUS_INTERFACE_SKELETON(da->iface));
     g_dbus_object_manager_server_export(da->server, da->audio);
+
+    return true;
 }
 
 static struct audio_pcm_ops dbus_pcm_ops = {

ui/dbus.c

@@ -221,15 +221,9 @@ dbus_display_complete(UserCreatable *uc, Error **errp)
 
     if (dd->audiodev && *dd->audiodev) {
         AudioBackend *audio_be = audio_be_by_name(dd->audiodev, errp);
-        if (!audio_be) {
+        if (!audio_be || !audio_be_set_dbus_server(audio_be, dd->server, dd->p2p, errp)) {
             return;
         }
-        if (!g_str_equal(audio_be->drv->name, "dbus")) {
-            error_setg(errp, "Audiodev '%s' is not compatible with DBus",
-                       dd->audiodev);
-            return;
-        }
-        audio_be->drv->set_dbus_server(audio_be, dd->server, dd->p2p);
     }
 
     consoles = g_array_new(FALSE, FALSE, sizeof(guint32));