drm/imx: ipuv3-plane: disable local alpha for planes without alpha channel

Without this patch, after enabling the overlay plane with an RGBA
framebuffer, switching to a framebuffer without alpha channel would
cause the plane to vanish, since the pixel local alpha is constant
zero in that case. Disable local alpha again when setting an opaque
framebuffer.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

diff --git a/drivers/gpu/drm/imx/ipuv3-plane.c b/drivers/gpu/drm/imx/ipuv3-plane.c
index e1ad844abafb5f9250c4597399d26eddf977af77..d5864ed4d772fdd2f4d5dfd0be9a13e372e27569 100644 (file)
--- a/drivers/gpu/drm/imx/ipuv3-plane.c
+++ b/drivers/gpu/drm/imx/ipuv3-plane.c
@@ -437,6 +437,7 @@ static void ipu_plane_atomic_update(struct drm_plane *plane,
                        ipu_dp_set_global_alpha(ipu_plane->dp, false, 0, false);
                        break;
                default:
+                       ipu_dp_set_global_alpha(ipu_plane->dp, true, 0, true);
                        break;
                }
        }