[PATCH v7 01/18] soc: mediatek: Disable 9-bit alpha in ETHDR

[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>
> 
> ETHDR 9-bit alpha should be disabled by default,
> otherwise alpha blending will not work.

Please explain what is 9-bit alpha. Is ARGB8888 8-bit alpha? I don't
know there are 9-bit alpha. I would like to know which function would
be disabled when you disable 9-bit alpha.

Regards,
CK

> 
> Reviewed-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno at collabora.com>
> Signed-off-by: Hsiao Chien Sung <shawn.sung at mediatek.com>
> ---
>  drivers/soc/mediatek/mtk-mmsys.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/soc/mediatek/mtk-mmsys.c
> b/drivers/soc/mediatek/mtk-mmsys.c
> index f370f4ec4b888..938240714e54c 100644
> --- a/drivers/soc/mediatek/mtk-mmsys.c
> +++ b/drivers/soc/mediatek/mtk-mmsys.c
> @@ -236,6 +236,7 @@ void mtk_mmsys_mixer_in_config(struct device
> *dev, int idx, bool alpha_sel, u16
>  
>  	mtk_mmsys_update_bits(mmsys, MT8195_VDO1_MIXER_IN1_ALPHA + (idx
> - 1) * 4, ~0,
>  			      alpha << 16 | alpha, cmdq_pkt);
> +	mtk_mmsys_update_bits(mmsys, MT8195_VDO1_HDR_TOP_CFG, BIT(15 +
> idx), 0, cmdq_pkt);
>  	mtk_mmsys_update_bits(mmsys, MT8195_VDO1_HDR_TOP_CFG, BIT(19 +
> idx),
>  			      alpha_sel << (19 + idx), cmdq_pkt);
>  	mtk_mmsys_update_bits(mmsys, MT8195_VDO1_MIXER_IN1_PAD + (idx -
> 1) * 4,