drm/blend: Add a generic alpha property
Some drivers duplicate the logic to create a property to store a per-plane
alpha.
This is especially useful if we ever want to support extra protocols for
Wayland like:
https://lists.freedesktop.org/archives/wayland-devel/2017-August/034741.html
Let's create a helper in order to move that to the core.
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/6e1ce0db78fcfc407e94913c64819e65109d034d.1523432341.git-series.maxime.ripard@bootlin.com
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index ee03c1e..0587a0a 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -3500,6 +3500,10 @@ void drm_atomic_helper_plane_reset(struct drm_plane *plane)
if (plane->state) {
plane->state->plane = plane;
plane->state->rotation = DRM_MODE_ROTATE_0;
+
+ /* Reset the alpha value to fully opaque if it matters */
+ if (plane->alpha_property)
+ plane->state->alpha = plane->alpha_property->values[1];
}
}
EXPORT_SYMBOL(drm_atomic_helper_plane_reset);