monitor-config-manager: Allow backends to assign extra data

When we're configuring monitors, allow backends to add backend specific
assignments during resource assignment (mapping connectors and CRTCs
etc).

This will later allow the native backend's KMS monitor resources to
assign a primary plane and optionally a cursor plane during
configuration. This will then dictate what plane will be used for
primary plane updates, as well as cursor updates, until reconfigured
again.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3428>

src/backends/meta-crtc.c

@@ -112,11 +112,17 @@ meta_crtc_get_all_transforms (MetaCrtc *crtc)
 
 void
 meta_crtc_set_config (MetaCrtc       *crtc,
-                      MetaCrtcConfig *config)
+                      MetaCrtcConfig *config,
+                      gpointer        backend_private)
 {
   MetaCrtcPrivate *priv = meta_crtc_get_instance_private (crtc);
+  MetaCrtcClass *klass = META_CRTC_GET_CLASS (crtc);
 
   meta_crtc_unset_config (crtc);
+
+  if (klass->set_config)
+    klass->set_config (crtc, config, backend_private);
+
   priv->config = config;
 }
 
@@ -136,6 +142,20 @@ meta_crtc_get_config (MetaCrtc *crtc)
   return priv->config;
 }
 
+gboolean
+meta_crtc_assign_extra (MetaCrtc            *crtc,
+                        MetaCrtcAssignment  *crtc_assignment,
+                        GPtrArray           *crtc_assignments,
+                        GError             **error)
+{
+  MetaCrtcClass *klass = META_CRTC_GET_CLASS (crtc);
+
+  if (klass->assign_extra)
+    return klass->assign_extra (crtc, crtc_assignment, crtc_assignments, error);
+  else
+    return TRUE;
+}
+
 size_t
 meta_crtc_get_gamma_lut_size (MetaCrtc *crtc)
 {

src/backends/meta-crtc.h

@@ -46,6 +46,15 @@ struct _MetaCrtcClass
 
   void (* set_gamma_lut) (MetaCrtc           *crtc,
                           const MetaGammaLut *lut);
+
+  gboolean (* assign_extra) (MetaCrtc            *crtc,
+                             MetaCrtcAssignment  *crtc_assignment,
+                             GPtrArray           *crtc_assignments,
+                             GError             **error);
+
+  void (* set_config) (MetaCrtc             *crtc,
+                       const MetaCrtcConfig *config,
+                       gpointer              backend_private);
 };
 
 META_EXPORT_TEST
@@ -71,7 +80,8 @@ MetaMonitorTransform meta_crtc_get_all_transforms (MetaCrtc *crtc);
 
 META_EXPORT_TEST
 void meta_crtc_set_config (MetaCrtc       *crtc,
-                           MetaCrtcConfig *config);
+                           MetaCrtcConfig *config,
+                           gpointer        backend_private);
 
 META_EXPORT_TEST
 void meta_crtc_unset_config (MetaCrtc *crtc);
@@ -79,6 +89,11 @@ void meta_crtc_unset_config (MetaCrtc *crtc);
 META_EXPORT_TEST
 const MetaCrtcConfig * meta_crtc_get_config (MetaCrtc *crtc);
 
+gboolean meta_crtc_assign_extra (MetaCrtc            *crtc,
+                                 MetaCrtcAssignment  *crtc_assignment,
+                                 GPtrArray           *crtc_assignments,
+                                 GError             **error);
+
 size_t meta_crtc_get_gamma_lut_size (MetaCrtc *crtc);
 
 MetaGammaLut * meta_crtc_get_gamma_lut (MetaCrtc *crtc);

src/backends/meta-monitor-config-manager.c

@@ -261,6 +261,12 @@ assign_monitor_crtc (MetaMonitor         *monitor,
   };
   g_ptr_array_add (crtc_assignment->outputs, output);
 
+  if (!meta_crtc_assign_extra (crtc,
+                               crtc_assignment,
+                               data->crtc_assignments,
+                               error))
+    return FALSE;
+
   /*
    * Only one output can be marked as primary (due to Xrandr limitation),
    * so only mark the main output of the first monitor in the logical monitor
@@ -1748,6 +1754,8 @@ meta_monitors_config_class_init (MetaMonitorsConfigClass *klass)
 static void
 meta_crtc_assignment_free (MetaCrtcAssignment *assignment)
 {
+  g_clear_pointer (&assignment->backend_private,
+                   assignment->backend_private_destroy);
   g_ptr_array_free (assignment->outputs, TRUE);
   g_free (assignment);
 }

src/backends/meta-monitor-manager-dummy.c

@@ -522,7 +522,8 @@ apply_crtc_assignments (MetaMonitorManager    *manager,
           crtc_config = meta_crtc_config_new (&crtc_assignment->layout,
                                               crtc_assignment->mode,
                                               crtc_assignment->transform);
-          meta_crtc_set_config (crtc, crtc_config);
+          meta_crtc_set_config (crtc, crtc_config,
+                                crtc_assignment->backend_private);
 
           for (j = 0; j < crtc_assignment->outputs->len; j++)
             {

src/backends/meta-monitor-manager-private.h

@@ -87,6 +87,9 @@ struct _MetaCrtcAssignment
   graphene_rect_t layout;
   MetaMonitorTransform transform;
   GPtrArray *outputs;
+
+  gpointer backend_private;
+  GDestroyNotify backend_private_destroy;
 };
 
 /*

src/backends/native/meta-monitor-manager-native.c

@@ -220,7 +220,8 @@ apply_crtc_assignments (MetaMonitorManager    *manager,
           crtc_config = meta_crtc_config_new (&crtc_assignment->layout,
                                               crtc_assignment->mode,
                                               crtc_assignment->transform);
-          meta_crtc_set_config (crtc, crtc_config);
+          meta_crtc_set_config (crtc, crtc_config,
+                                crtc_assignment->backend_private);
 
           for (j = 0; j < crtc_assignment->outputs->len; j++)
             {

src/backends/x11/meta-crtc-xrandr.c

@@ -293,7 +293,7 @@ meta_crtc_xrandr_new (MetaGpuXrandr      *gpu_xrandr,
                                                    crtc_xrandr->rect.height),
                               crtc_xrandr->current_mode,
                               crtc_xrandr->transform);
-      meta_crtc_set_config (META_CRTC (crtc_xrandr), crtc_config);
+      meta_crtc_set_config (META_CRTC (crtc_xrandr), crtc_config, NULL);
     }
 
   return crtc_xrandr;

src/backends/x11/meta-monitor-manager-xrandr.c

@@ -560,7 +560,8 @@ apply_crtc_assignments (MetaMonitorManager    *manager,
           crtc_config = meta_crtc_config_new (&crtc_assignment->layout,
                                               crtc_mode,
                                               crtc_assignment->transform);
-          meta_crtc_set_config (crtc, crtc_config);
+          meta_crtc_set_config (crtc, crtc_config,
+                                crtc_assignment->backend_private);
         }
     }
 

src/tests/meta-monitor-manager-test.c

@@ -184,7 +184,8 @@ apply_crtc_assignments (MetaMonitorManager    *manager,
           crtc_config = meta_crtc_config_new (&crtc_assignment->layout,
                                               crtc_assignment->mode,
                                               crtc_assignment->transform);
-          meta_crtc_set_config (crtc, crtc_config);
+          meta_crtc_set_config (crtc, crtc_config,
+                                crtc_assignment->backend_private);
 
           for (j = 0; j < crtc_assignment->outputs->len; j++)
             {