Re: [PATCH v14 05/10] drm/mediatek: Add MT8195 Embedded DisplayPort driver

[CK Hu <ck.hu@mediatek.com>]

Hi, Bo-Chen:

On Tue, 2022-07-12 at 19:12 +0800, Bo-Chen Chen wrote:
> From: Markus Schneider-Pargmann <msp@baylibre.com>
> 
> 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@mediatek.com>
> 
> Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
> Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>
> Signed-off-by: Bo-Chen Chen <rex-bc.chen@mediatek.com>
> ---

[snip]

> +
> +static void mtk_dp_set_msa(struct mtk_dp *mtk_dp)
> +{
> +	struct drm_display_mode mode;
> +	struct mtk_dp_timings *timings = &mtk_dp->info.timings;
> +
> +	drm_display_mode_from_videomode(&timings->vm, &mode);
> +
> +	/* horizontal */
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3010,
> +			   mode.htotal, HTOTAL_SW_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3018,
> +			   timings->vm.hsync_len + timings-
> >vm.hback_porch,
> +			   HSTART_SW_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3028,
> +			   timings->vm.hsync_len <<
> HSW_SW_DP_ENC0_P0_SHIFT,

Directly use a number for shift because we know it's a shift, so it's
not necessary to define a symbol for shift.

> +			   HSW_SW_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3028,
> +			   0, HSP_SW_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3020,
> +			   timings->vm.hactive,
> HWIDTH_SW_DP_ENC0_P0_MASK);
> +
> +	/* vertical */
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3014,
> +			   mode.vtotal, VTOTAL_SW_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_301C,
> +			   timings->vm.vsync_len + timings-
> >vm.vback_porch,
> +			   VSTART_SW_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_302C,
> +			   timings->vm.vsync_len <<
> VSW_SW_DP_ENC0_P0_SHIFT,

Ditto.

Regards,
CK

> +			   VSW_SW_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_302C,
> +			   0, VSP_SW_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3024,
> +			   timings->vm.vactive,
> VHEIGHT_SW_DP_ENC0_P0_MASK);
> +
> +	/* horizontal */
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3064,
> +			   timings->vm.hactive,
> HDE_NUM_LAST_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3154,
> +			   mode.htotal, PGEN_HTOTAL_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3158,
> +			   timings->vm.hfront_porch,
> +			   PGEN_HSYNC_RISING_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_315C,
> +			   timings->vm.hsync_len,
> +			   PGEN_HSYNC_PULSE_WIDTH_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3160,
> +			   timings->vm.hback_porch + timings-
> >vm.hsync_len,
> +			   PGEN_HFDE_START_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3164,
> +			   timings->vm.hactive,
> +			   PGEN_HFDE_ACTIVE_WIDTH_DP_ENC0_P0_MASK);
> +
> +	/* vertical */
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3168,
> +			   mode.vtotal,
> +			   PGEN_VTOTAL_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_316C,
> +			   timings->vm.vfront_porch,
> +			   PGEN_VSYNC_RISING_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3170,
> +			   timings->vm.vsync_len,
> +			   PGEN_VSYNC_PULSE_WIDTH_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3174,
> +			   timings->vm.vback_porch + timings-
> >vm.vsync_len,
> +			   PGEN_VFDE_START_DP_ENC0_P0_MASK);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3178,
> +			   timings->vm.vactive,
> +			   PGEN_VFDE_ACTIVE_WIDTH_DP_ENC0_P0_MASK);
> +}
> +