[PATCH v9 12/21] drm/mediatek: Support DRM plane alpha in OVL

[CK Hu (胡俊光)]

Hi, Shawn:

On Fri, 2024-06-14 at 10:46 +0800, Shawn Sung wrote:
> From: Hsiao Chien Sung <shawn.sung at mediatek.com>
> 
> Set the plane alpha according to DRM plane property.

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_disp_ovl.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> index 1923bbd96014..2316d4a6dca7 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> @@ -450,8 +450,10 @@ void mtk_ovl_layer_config(struct device *dev, unsigned int idx,
>  	}
>  
>  	con = ovl_fmt_convert(ovl, fmt);
> -	if (state->base.fb && state->base.fb->format->has_alpha)
> -		con |= OVL_CON_AEN | OVL_CON_ALPHA;
> +	if (state->base.fb) {
> +		con |= OVL_CON_AEN;
> +		con |= state->base.alpha & OVL_CON_ALPHA;
> +	}
>  
>  	/* CONST_BLD must be enabled for XRGB formats although the alpha channel
>  	 * can be ignored, or OVL will still read the value from memory.