Re: [PATCH v10 18/21] drm/mediatek: Add mt8195 Embedded DisplayPort driver

[CK Hu]

Hi, Rex:

On Mon, 2022-05-23 at 12:47 +0200, Guillaume Ranquet wrote:
> From: Markus Schneider-Pargmann <msp@xxxxxxxxxxxx>
> 
> This patch adds a DisplayPort driver for the Mediatek mt8195 SoC.
> 
> It supports the mt8195, the embedded DisplayPort units. It offers
> DisplayPort 1.4 with up to 4 lanes.
> 
> The driver creates a child device for the phy. The child device will
> never exist without the parent being active. As they are sharing a
> register range, the parent passes a regmap pointer to the child so
> that
> both can work with the same register range. The phy driver sets
> device
> data that is read by the parent to get the phy device that can be
> used
> to control the phy properties.
> 
> This driver is based on an initial version by
> Jason-JH.Lin <jason-jh.lin@xxxxxxxxxxxx>.
> 
> Signed-off-by: Markus Schneider-Pargmann <msp@xxxxxxxxxxxx>
> Signed-off-by: Guillaume Ranquet <granquet@xxxxxxxxxxxx>
> ---

[snip]

> +
> +static void mtk_dp_state_handler(struct mtk_dp *mtk_dp)
> +{
> +	switch (mtk_dp->state) {

Does mtk_dp->state has any relation with mtk_dp->train_state. If yes,
mix mtk_dp->state and mtk_dp->train_state into one state. If no, move
calling mtk_dp_state_handler() out of mtk_dp_train_handler().

Regards,
CK

> +	case MTK_DP_STATE_INITIAL:
> +		mtk_dp_video_mute(mtk_dp, true);
> +		mtk_dp->state = MTK_DP_STATE_IDLE;
> +		break;
> +
> +	case MTK_DP_STATE_IDLE:
> +		if (mtk_dp->train_state == MTK_DP_TRAIN_STATE_NORMAL)
> +			mtk_dp->state = MTK_DP_STATE_PREPARE;
> +		break;
> +
> +	case MTK_DP_STATE_PREPARE:
> +		mtk_dp_video_config(mtk_dp);
> +		mtk_dp_video_enable(mtk_dp, true);
> +
> +		mtk_dp->state = MTK_DP_STATE_NORMAL;
> +		break;
> +
> +	case MTK_DP_STATE_NORMAL:
> +		if (mtk_dp->train_state != MTK_DP_TRAIN_STATE_NORMAL) {
> +			mtk_dp_video_mute(mtk_dp, true);
> +			mtk_dp->state = MTK_DP_STATE_IDLE;
> +		}
> +		break;
> +
> +	default:
> +		break;
> +	}
> +}