Re: [PATCH v12 05/10] drm/mediatek: Add MT8195 Embedded DisplayPort driver

From: CK Hu
Date: Wed Jun 29 2022 - 22:43:22 EST


Hi, Bo-Chen:

On Mon, 2022-06-27 at 16:03 +0800, Bo-Chen Chen wrote:
> From: Markus Schneider-Pargmann <msp@xxxxxxxxxxxx>
>
> This patch adds a embedded 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
> Jitao shi <jitao.shi@xxxxxxxxxxxx>
>
> Signed-off-by: Markus Schneider-Pargmann <msp@xxxxxxxxxxxx>
> Signed-off-by: Guillaume Ranquet <granquet@xxxxxxxxxxxx>
> [Bo-Chen: Cleanup the drivers and modify comments from reviewers]
> Signed-off-by: Bo-Chen Chen <rex-bc.chen@xxxxxxxxxxxx>
> ---

[snip]

> +
> +static void mtk_dp_set_color_depth(struct mtk_dp *mtk_dp)
> +{
> + u32 val;
> + /* Only support 8 bits currently */
> + u32 color_depth = DP_MSA_MISC_8_BPC;
> +
> + mtk_dp->info.depth = color_depth;
> +
> + /* Update MISC0 */
> + mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3034,
> + color_depth, DP_TEST_BIT_DEPTH_MASK);
> +
> + switch (color_depth) {
> + case DP_MSA_MISC_6_BPC:
> + val = VIDEO_COLOR_DEPTH_DP_ENC0_P0_6BIT;
> + break;
> + case DP_MSA_MISC_8_BPC:
> + val = VIDEO_COLOR_DEPTH_DP_ENC0_P0_8BIT;

This driver just use DP_MSA_MISC_8_BPC, so keep this and drop others.

Regards,
CK

> + break;
> + case DP_MSA_MISC_10_BPC:
> + val = VIDEO_COLOR_DEPTH_DP_ENC0_P0_10BIT;
> + break;
> + case DP_MSA_MISC_12_BPC:
> + val = VIDEO_COLOR_DEPTH_DP_ENC0_P0_12BIT;
> + break;
> + case DP_MSA_MISC_16_BPC:
> + val = VIDEO_COLOR_DEPTH_DP_ENC0_P0_16BIT;
> + break;
> + default:
> + drm_warn(mtk_dp->drm_dev, "Unsupported color depth
> %d\n",
> + color_depth);
> + return;
> + }
> +
> + mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_303C, val,
> + VIDEO_COLOR_DEPTH_DP_ENC0_P0_MASK);
> +}
> +