Re: [PATCH v11 05/10] drm/mediatek: Add MT8195 Embedded DisplayPort driver

[CK Hu]

Hi, Bo-Chen:

On Fri, 2022-06-10 at 18:55 +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]

> +
> +/* multiple of 0.27Gbps */
> +enum mtk_dp_linkrate {
> +	MTK_DP_LINKRATE_RBR = 0x6,
> +	MTK_DP_LINKRATE_HBR = 0xA,
> +	MTK_DP_LINKRATE_HBR2 = 0x14,
> +	MTK_DP_LINKRATE_HBR25 = 0x19,
> +	MTK_DP_LINKRATE_HBR3 = 0x1E,
> +};

Use the definition in drm_dp.h:

/* Link Configuration */
#define	DP_LINK_BW_SET		            0x100
# define DP_LINK_RATE_TABLE		    0x00    /* eDP 1.4 */
# define DP_LINK_BW_1_62		    0x06
# define DP_LINK_BW_2_7			    0x0a
# define DP_LINK_BW_5_4			    0x14    /* 1.2 */
# define DP_LINK_BW_8_1			    0x1e    /* 1.4 */
# define DP_LINK_BW_10                      0x01    /* 2.0 128b/132b
Link Layer */
# define DP_LINK_BW_13_5                    0x04    /* 2.0 128b/132b
Link Layer */
# define DP_LINK_BW_20                      0x02    /* 2.0 128b/132b
Link Layer */

Regards,
CK

> 
>