Merge tag 'imx-drm-fixes-2017-11-30' of git://git.pengutronix.de/git/pza/linux into drm-fixes

drm/imx: fix commit_tail for new drm_atomic_helper_setup_commit

Since commit 080de2e5 ("drm/atomic: Check for busy planes/connectors before
setting the commit"), drm_atomic_helper_setup_commit expects that blocking
commits have completed flipping before the commit_tail returns. Add the missing
wait_for_flip_done to commit_tail to ensure this.

* tag 'imx-drm-fixes-2017-11-30' of git://git.pengutronix.de/git/pza/linux:
  drm/imx: always call wait_for_flip_done in commit_tail

drivers/gpu/drm/imx/imx-drm-core.c

@@ -133,9 +133,16 @@ static void imx_drm_atomic_commit_tail(struct drm_atomic_state *state)
 			plane_disabling = true;
 	}
 
-	if (plane_disabling) {
-		drm_atomic_helper_wait_for_vblanks(dev, state);
+	/*
+	 * The flip done wait is only strictly required by imx-drm if a deferred
+	 * plane disable is in-flight. As the core requires blocking commits
+	 * to wait for the flip it is done here unconditionally. This keeps the
+	 * workitem around a bit longer than required for the majority of
+	 * non-blocking commits, but we accept that for the sake of simplicity.
+	 */
+	drm_atomic_helper_wait_for_flip_done(dev, state);
 
+	if (plane_disabling) {
 		for_each_old_plane_in_state(state, plane, old_plane_state, i)
 			ipu_plane_disable_deferred(plane);