drm/fb-helper: Push down modeset lock into FB helpers

Move the modeset locking from drivers into FB helpers.

v2: Also handle intel_connector_add_to_fbdev.

v3: Prevent race in intel_dp_mst with ->detect (Maarten)

Cc: Maarten Lankhorst <[email protected]>
Cc: Alex Deucher <[email protected]>
Cc: Christian König <[email protected]>
Tested-by: John Stultz <[email protected]>
Signed-off-by: Thierry Reding <[email protected]> (v1)
Reviewed-by: Maarten Lankhorst <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]

1 files changed, 3 insertions, 6 deletions

diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c
index 2cf046beae0f..9aa959284497 100644
--- a/drivers/gpu/drm/i915/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/intel_dp_mst.c
@@ -501,11 +501,8 @@ static struct drm_connector *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
 static void intel_dp_register_mst_connector(struct drm_connector *connector)
 {
 	struct intel_connector *intel_connector = to_intel_connector(connector);
-	struct drm_device *dev = connector->dev;
 
-	drm_modeset_lock_all(dev);
 	intel_connector_add_to_fbdev(intel_connector);
-	drm_modeset_unlock_all(dev);
 
 	drm_connector_register(&intel_connector->base);
 }
@@ -514,15 +511,15 @@ static void intel_dp_destroy_mst_connector(struct drm_dp_mst_topology_mgr *mgr,
 					   struct drm_connector *connector)
 {
 	struct intel_connector *intel_connector = to_intel_connector(connector);
-	struct drm_device *dev = connector->dev;
 
 	drm_connector_unregister(connector);
 
 	/* need to nuke the connector */
-	drm_modeset_lock_all(dev);
 	intel_connector_remove_from_fbdev(intel_connector);
+	/* prevent race with the check in ->detect */
+	drm_modeset_lock(&connector->dev->mode_config.connection_mutex, NULL);
 	intel_connector->mst_port = NULL;
-	drm_modeset_unlock_all(dev);
+	drm_modeset_unlock(&connector->dev->mode_config.connection_mutex);
 
 	drm_connector_unreference(&intel_connector->base);
 	DRM_DEBUG_KMS("\n");