[mutter] renderer-native: Unset mode on disabled CRTCs

[Jonas Ådahl <jadahl src gnome org>]

commit 20749e5dbd15f6125519b241e989d985a0d5ccdf
Author: Jonas Ådahl <jadahl gmail com>
Date:   Thu Sep 28 11:59:27 2017 -0400

    renderer-native: Unset mode on disabled CRTCs
    
    Make sure we properly unset the CRTC mode when a monitor is disabled.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=787629

 src/backends/native/meta-renderer-native.c |   26 ++++++++++++++++++++++++++
 src/backends/native/meta-stage-native.c    |    1 +
 2 files changed, 27 insertions(+), 0 deletions(-)
---
diff --git a/src/backends/native/meta-renderer-native.c b/src/backends/native/meta-renderer-native.c
index 7559708..4d1d890 100644
--- a/src/backends/native/meta-renderer-native.c
+++ b/src/backends/native/meta-renderer-native.c
@@ -132,6 +132,7 @@ struct _MetaRendererNative
   CoglClosure *swap_notify_idle;
 
   int64_t frame_counter;
+  gboolean pending_unset_disabled_crtcs;
 
   gboolean no_add_fb2;
 };
@@ -1396,6 +1397,8 @@ meta_renderer_native_queue_modes_reset (MetaRendererNative *renderer_native)
 
       onscreen_native->pending_set_crtc = TRUE;
     }
+
+  renderer_native->pending_unset_disabled_crtcs = TRUE;
 }
 
 static CoglOnscreen *
@@ -1778,6 +1781,29 @@ void
 meta_renderer_native_finish_frame (MetaRendererNative *renderer_native)
 {
   renderer_native->frame_counter++;
+
+  if (renderer_native->pending_unset_disabled_crtcs)
+    {
+      MetaBackend *backend = meta_get_backend ();
+      MetaMonitorManager *monitor_manager =
+        meta_backend_get_monitor_manager (backend);
+      MetaMonitorManagerKms *monitor_manager_kms =
+        META_MONITOR_MANAGER_KMS (monitor_manager);
+      unsigned int i;
+
+      for (i = 0; i < monitor_manager->n_crtcs; i++)
+        {
+          MetaCrtc *crtc = &monitor_manager->crtcs[i];
+
+          if (crtc->current_mode)
+            continue;
+
+          meta_monitor_manager_kms_apply_crtc_mode (monitor_manager_kms,
+                                                    crtc, 0, 0, 0);
+        }
+
+      renderer_native->pending_unset_disabled_crtcs = FALSE;
+    }
 }
 
 int64_t
diff --git a/src/backends/native/meta-stage-native.c b/src/backends/native/meta-stage-native.c
index 82ede47..3a39f93 100644
--- a/src/backends/native/meta-stage-native.c
+++ b/src/backends/native/meta-stage-native.c
@@ -160,6 +160,7 @@ meta_stage_native_rebuild_views (MetaStageNative *stage_native)
   MetaRenderer *renderer = meta_backend_get_renderer (backend);
 
   meta_renderer_rebuild_views (renderer);
+  meta_renderer_native_queue_modes_reset (META_RENDERER_NATIVE (renderer));
   ensure_frame_callbacks (stage_native);
 }