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]
> +
> +static int mtk_dp_train_set_pattern(struct mtk_dp *mtk_dp, int
> pattern)
> +{
> + if (pattern < 0 || pattern > 4) {
The caller would pass pattern from 0 to 4, so this checking is
redundant. Remove it and this function would always return true, so let
this function be void.
Regards,
CK
> + drm_err(mtk_dp->drm_dev,
> + "Implementation error, no such pattern %d\n",
> pattern);
> + return -EINVAL;
> + }
> +
> + /* TPS1 */
> + if (pattern == 1)
> + mtk_dp_set_idle_pattern(mtk_dp, false);
> +
> + mtk_dp_update_bits(mtk_dp,
> + MTK_DP_TRANS_P0_3400,
> + pattern ?
> + BIT(pattern - 1) <<
> PATTERN1_EN_DP_TRANS_P0_SHIFT :
> + 0,
> + PATTERN1_EN_DP_TRANS_P0_MASK |
> + PATTERN2_EN_DP_TRANS_P0_MASK |
> + PATTERN3_EN_DP_TRANS_P0_MASK |
> + PATTERN4_EN_DP_TRANS_P0_MASK);
> + return 0;
> +}
