[PATCH 4.19 042/110] drm/vc4: Set ->legacy_cursor_update to false when doing non-async updates

[Greg Kroah-Hartman]

4.19-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Boris Brezillon <boris.brezillon@xxxxxxxxxxx>

commit fcc86cb45d38ca2f24bcea9c29c7f4742041caed upstream.

drm_atomic_helper_setup_commit() auto-completes commit->flip_done when
state->legacy_cursor_update is true, but we know for sure that we want
a sync update when we call drm_atomic_helper_setup_commit() from
vc4_atomic_commit().

Explicitly set state->legacy_cursor_update to false to prevent this
auto-completion.

Fixes: 184d3cf4f738 ("drm/vc4: Use wait_for_flip_done() instead of wait_for_vblanks()")
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxx>
Reviewed-by: Eric Anholt <eric@xxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20181115105852.9844-2-boris.brezillon@xxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/gpu/drm/vc4/vc4_kms.c |    6 ++++++
 1 file changed, 6 insertions(+)

--- a/drivers/gpu/drm/vc4/vc4_kms.c
+++ b/drivers/gpu/drm/vc4/vc4_kms.c
@@ -216,6 +216,12 @@ static int vc4_atomic_commit(struct drm_
 		return 0;
 	}
 
+	/* We know for sure we don't want an async update here. Set
+	 * state->legacy_cursor_update to false to prevent
+	 * drm_atomic_helper_setup_commit() from auto-completing
+	 * commit->flip_done.
+	 */
+	state->legacy_cursor_update = false;
 	ret = drm_atomic_helper_setup_commit(state, nonblock);
 	if (ret)
 		return ret;