Merge drm/drm-next into drm-intel-next-queued

[sfrench/cifs-2.6.git] / drivers / gpu / drm / drm_atomic.c

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 0da8c5e134b2fb5502c0e92282c5fdfa0d68aecf..3c181d217f8b1ae7361ba035faf58fa50d0975b6 100644 (file)
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -783,6 +783,8 @@ static int drm_atomic_plane_set_property(struct drm_plane *plane,
                state->src_w = val;
        } else if (property == config->prop_src_h) {
                state->src_h = val;
+       } else if (property == plane->alpha_property) {
+               state->alpha = val;
        } else if (property == plane->rotation_property) {
                if (!is_power_of_2(val & DRM_MODE_ROTATE_MASK))
                        return -EINVAL;
@@ -848,6 +850,8 @@ drm_atomic_plane_get_property(struct drm_plane *plane,
                *val = state->src_w;
        } else if (property == config->prop_src_h) {
                *val = state->src_h;
+       } else if (property == plane->alpha_property) {
+               *val = state->alpha;
        } else if (property == plane->rotation_property) {
                *val = state->rotation;
        } else if (property == plane->zpos_property) {
@@ -1492,6 +1496,14 @@ EXPORT_SYMBOL(drm_atomic_set_fb_for_plane);
  * Otherwise, if &drm_plane_state.fence is not set this function we just set it
  * with the received implicit fence. In both cases this function consumes a
  * reference for @fence.
+ *
+ * This way explicit fencing can be used to overrule implicit fencing, which is
+ * important to make explicit fencing use-cases work: One example is using one
+ * buffer for 2 screens with different refresh rates. Implicit fencing will
+ * clamp rendering to the refresh rate of the slower screen, whereas explicit
+ * fence allows 2 independent render and display loops on a single buffer. If a
+ * driver allows obeys both implicit and explicit fences for plane updates, then
+ * it will break all the benefits of explicit fencing.
  */
 void
 drm_atomic_set_fence_for_plane(struct drm_plane_state *plane_state,