kms: Update device state when resuming

Suspending might have changed the CRTC configuration, turning some off,
some on, etc. We need to update our internal representation of this
state, so that we know how to reconfigure upon resuming, e.g. what CRTCs
to turn off again.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1488>

src/backends/native/meta-backend-native.c

@@ -652,6 +652,7 @@ void meta_backend_native_resume (MetaBackendNative *native)
                            "Backend (resume)");
 
   meta_monitor_manager_kms_resume (monitor_manager_kms);
+  meta_kms_resume (native->kms);
 
   connect_udev_device_added_handler (native);
 

src/backends/native/meta-kms.c

@@ -573,6 +573,12 @@ handle_hotplug_event (MetaKms *kms)
   g_signal_emit (kms, signals[RESOURCES_CHANGED], 0);
 }
 
+void
+meta_kms_resume (MetaKms *kms)
+{
+  handle_hotplug_event (kms);
+}
+
 static void
 on_udev_hotplug (MetaUdev *udev,
                  MetaKms  *kms)

src/backends/native/meta-kms.h

@@ -50,6 +50,8 @@ MetaBackend * meta_kms_get_backend (MetaKms *kms);
 
 GList * meta_kms_get_devices (MetaKms *kms);
 
+void meta_kms_resume (MetaKms *kms);
+
 MetaKmsDevice * meta_kms_create_device (MetaKms            *kms,
                                         const char         *path,
                                         MetaKmsDeviceFlag   flags,

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

@@ -516,7 +516,6 @@ void
 meta_monitor_manager_kms_resume (MetaMonitorManagerKms *manager_kms)
 {
   meta_monitor_manager_kms_connect_hotplug_handler (manager_kms);
-  handle_hotplug_event (META_MONITOR_MANAGER (manager_kms));
 }
 
 static gboolean