[PATCH v7 14/18] drm/mediatek: Support "None" blending in Mixer

[CK Hu (胡俊光)]

Hi, Shawn:

On Thu, 2024-05-02 at 18:38 +0800, Shawn Sung wrote:
> From: Hsiao Chien Sung <shawn.sung at mediatek.com>
> 
> Support "None" alpha blending mode on MediaTek's chips.

Reviewed-by: CK Hu <ck.hu at mediatek.com>

> 
> Signed-off-by: Hsiao Chien Sung <shawn.sung at mediatek.com>
> ---
>  drivers/gpu/drm/mediatek/mtk_ethdr.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_ethdr.c
> b/drivers/gpu/drm/mediatek/mtk_ethdr.c
> index 4f043be21ee36..91ebeee6c8b1d 100644
> --- a/drivers/gpu/drm/mediatek/mtk_ethdr.c
> +++ b/drivers/gpu/drm/mediatek/mtk_ethdr.c
> @@ -180,7 +180,8 @@ void mtk_ethdr_layer_config(struct device *dev,
> unsigned int idx,
>  	else
>  		mix_con |= NON_PREMULTI_SOURCE;
>  
> -	if (state->base.fb && !state->base.fb->format->has_alpha) {
> +	if (state->base.pixel_blend_mode == DRM_MODE_BLEND_PIXEL_NONE
> ||
> +	    (state->base.fb && !state->base.fb->format->has_alpha)) {
>  		/*
>  		 * Mixer doesn't support CONST_BLD mode,
>  		 * use a trick to make the output equivalent