Merge tag 'v4.3-rc2' into topic/drm-misc

[karo-tx-linux.git] / drivers / gpu / drm / drm_atomic.c

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index f7d5166f89b24ef740e854175927ad934652fed4..940f80bbf1925a29d332a31f9ac9c0127031a2fd 100644 (file)
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -663,6 +663,25 @@ drm_atomic_plane_get_property(struct drm_plane *plane,
        return 0;
 }
 
+static bool
+plane_switching_crtc(struct drm_atomic_state *state,
+                    struct drm_plane *plane,
+                    struct drm_plane_state *plane_state)
+{
+       if (!plane->state->crtc || !plane_state->crtc)
+               return false;
+
+       if (plane->state->crtc == plane_state->crtc)
+               return false;
+
+       /* This could be refined, but currently there's no helper or driver code
+        * to implement direct switching of active planes nor userspace to take
+        * advantage of more direct plane switching without the intermediate
+        * full OFF state.
+        */
+       return true;
+}
+
 /**
  * drm_atomic_plane_check - check plane state
  * @plane: plane to check
@@ -734,6 +753,12 @@ static int drm_atomic_plane_check(struct drm_plane *plane,
                return -ENOSPC;
        }
 
+       if (plane_switching_crtc(state->state, plane, state)) {
+               DRM_DEBUG_ATOMIC("[PLANE:%d] switching CRTC directly\n",
+                                plane->base.id);
+               return -EINVAL;
+       }
+
        return 0;
 }