[PATCH v2 06/11] drm/mediatek: Support alpha blending in display driver

[Hsiao Chien Sung]

Support alpha blending by adding correct blend mode and
alpha property in plane initialization.

Reviewed-by: AngeloGioacchino Del Regno 
<angelogioacchino.delre...@collabora.com>
Signed-off-by: Hsiao Chien Sung <shawn.s...@mediatek.com>
---
 drivers/gpu/drm/mediatek/mtk_drm_plane.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c 
b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
index db2f70ae060d..f87cf56fb846 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
@@ -301,6 +301,9 @@ int mtk_plane_init(struct drm_device *dev, struct drm_plane 
*plane,
                   size_t num_formats)
 {
        int err;
+       u32 blend_mode = BIT(DRM_MODE_BLEND_PIXEL_NONE) |
+                        BIT(DRM_MODE_BLEND_PREMULTI)   |
+                        BIT(DRM_MODE_BLEND_COVERAGE);
 
        if (!formats || !num_formats) {
                DRM_ERROR("no formats for plane\n");
@@ -323,6 +326,14 @@ int mtk_plane_init(struct drm_device *dev, struct 
drm_plane *plane,
                        DRM_INFO("Create rotation property failed\n");
        }
 
+       err = drm_plane_create_alpha_property(plane);
+       if (err)
+               DRM_ERROR("failed to create property: alpha\n");
+
+       err = drm_plane_create_blend_mode_property(plane, blend_mode);
+       if (err)
+               DRM_ERROR("failed to create property: blend_mode\n");
+
        drm_plane_helper_add(plane, &mtk_plane_helper_funcs);
 
        return 0;
-- 
2.18.0