Merge tag 's390-6.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

[linux-block.git] / include / drm / drm_modeset_helper_vtables.h

diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h
index 206f495bbf06af49c598427f0720b2cdd5437cbd..965faf082a6d1acbe894ad6f1849fc00e3979b90 100644 (file)
--- a/include/drm/drm_modeset_helper_vtables.h
+++ b/include/drm/drm_modeset_helper_vtables.h
@@ -1331,6 +1331,32 @@ struct drm_plane_helper_funcs {
         */
        void (*atomic_update)(struct drm_plane *plane,
                              struct drm_atomic_state *state);
+
+       /**
+        * @atomic_enable:
+        *
+        * Drivers should use this function to unconditionally enable a plane.
+        * This hook is called in-between the &drm_crtc_helper_funcs.atomic_begin
+        * and drm_crtc_helper_funcs.atomic_flush callbacks. It is called after
+        * @atomic_update, which will be called for all enabled planes. Drivers
+        * that use @atomic_enable should set up a plane in @atomic_update and
+        * afterwards enable the plane in @atomic_enable. If a plane needs to be
+        * enabled before installing the scanout buffer, drivers can still do
+        * so in @atomic_update.
+        *
+        * Note that the power state of the display pipe when this function is
+        * called depends upon the exact helpers and calling sequence the driver
+        * has picked. See drm_atomic_helper_commit_planes() for a discussion of
+        * the tradeoffs and variants of plane commit helpers.
+        *
+        * This callback is used by the atomic modeset helpers, but it is
+        * optional. If implemented, @atomic_enable should be the inverse of
+        * @atomic_disable. Drivers that don't want to use either can still
+        * implement the complete plane update in @atomic_update.
+        */
+       void (*atomic_enable)(struct drm_plane *plane,
+                             struct drm_atomic_state *state);
+
        /**
         * @atomic_disable:
         *
@@ -1351,7 +1377,8 @@ struct drm_plane_helper_funcs {
         * the tradeoffs and variants of plane commit helpers.
         *
         * This callback is used by the atomic modeset helpers and by the
-        * transitional plane helpers, but it is optional.
+        * transitional plane helpers, but it is optional. It's intended to
+        * reverse the effects of @atomic_enable.
         */
        void (*atomic_disable)(struct drm_plane *plane,
                               struct drm_atomic_state *state);