From: Hsiao Chien Sung <shawn.sung@xxxxxxxxxxxx> When 9-bit alpha is enabled, its value will be converted from 0-255 to 0-256 (255 = not defined). This is designed for special HDR related calculation, which should be disabled by default, otherwise, alpha blending will not work correctly. Fixes: 119f5173628a ("drm/mediatek: Add DRM Driver for Mediatek SoC MT8173.") Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx> Reviewed-by: CK Hu <ck.hu@xxxxxxxxxxxx> Signed-off-by: Hsiao Chien Sung <shawn.sung@xxxxxxxxxxxx> --- drivers/gpu/drm/mediatek/mtk_ethdr.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_ethdr.c b/drivers/gpu/drm/mediatek/mtk_ethdr.c index 156c6ff547e8..d7d16482c947 100644 --- a/drivers/gpu/drm/mediatek/mtk_ethdr.c +++ b/drivers/gpu/drm/mediatek/mtk_ethdr.c @@ -50,7 +50,6 @@ #define MIXER_INX_MODE_BYPASS 0 #define MIXER_INX_MODE_EVEN_EXTEND 1 -#define DEFAULT_9BIT_ALPHA 0x100 #define MIXER_ALPHA_AEN BIT(8) #define MIXER_ALPHA 0xff #define ETHDR_CLK_NUM 13 @@ -169,7 +168,7 @@ void mtk_ethdr_layer_config(struct device *dev, unsigned int idx, alpha_con = MIXER_ALPHA_AEN | MIXER_ALPHA; mtk_mmsys_mixer_in_config(priv->mmsys_dev, idx + 1, alpha_con ? false : true, - DEFAULT_9BIT_ALPHA, + MIXER_ALPHA, pending->x & 1 ? MIXER_INX_MODE_EVEN_EXTEND : MIXER_INX_MODE_BYPASS, align_width / 2 - 1, cmdq_pkt); -- Git-146)