drm: make sure visible is set to false if fb is null

We can't let visible set true while the fb is null, some places of
the code only check for visible to base its decisions.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/drm_plane_helper.c b/drivers/gpu/drm/drm_plane_helper.c
index 827ec1a..fe4d1fb 100644 (file)
--- a/drivers/gpu/drm/drm_plane_helper.c
+++ b/drivers/gpu/drm/drm_plane_helper.c
@@ -127,6 +127,11 @@ int drm_plane_helper_check_update(struct drm_plane *plane,
                return -ERANGE;
        }
 
+       if (!fb) {
+               *visible = false;
+               return 0;
+       }
+
        *visible = drm_rect_clip_scaled(src, dest, clip, hscale, vscale);
        if (!*visible)
                /*