drm/mediatek: ovl: Refine ignore_pixel_alpha comment and placement

Refine the comment for ignore_pixel_alpha flag and move it to
if(state->fb) statement to make it less conditional.

Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20241009034646.13143-3-jason-jh.lin@mediatek.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
index 047cd17..0d3a9c5 100644 (file)
--- a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
@@ -481,16 +481,16 @@ void mtk_ovl_layer_config(struct device *dev, unsigned int idx,
                 */
                if (blend_mode || state->base.fb->format->has_alpha)
                        con |= OVL_CON_AEN;
-       }
 
-       /* CONST_BLD must be enabled for XRGB formats although the alpha channel
-        * can be ignored, or OVL will still read the value from memory.
-        * For RGB888 related formats, whether CONST_BLD is enabled or not won't
-        * affect the result. Therefore we use !has_alpha as the condition.
-        */
-       if ((state->base.fb && !state->base.fb->format->has_alpha) ||
-           blend_mode == DRM_MODE_BLEND_PIXEL_NONE)
-               ignore_pixel_alpha = OVL_CONST_BLEND;
+               /*
+                * Although the alpha channel can be ignored, CONST_BLD must be enabled
+                * for XRGB format, otherwise OVL will still read the value from memory.
+                * For RGB888 related formats, whether CONST_BLD is enabled or not won't
+                * affect the result. Therefore we use !has_alpha as the condition.
+                */
+               if (blend_mode == DRM_MODE_BLEND_PIXEL_NONE || !state->base.fb->format->has_alpha)
+                       ignore_pixel_alpha = OVL_CONST_BLEND;
+       }
 
        if (pending->rotation & DRM_MODE_REFLECT_Y) {
                con |= OVL_CON_VIRT_FLIP;