Re: [PATCH v17 08/10] drm/mediatek: dp: Add MT8195 External DisplayPort support

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

Hi, Bo-Chen:

On Thu, 2022-09-01 at 12:41 +0800, Bo-Chen Chen wrote:
> From: Guillaume Ranquet <granquet@baylibre.com>
> 
> Add External DisplayPort support to the MT8195 eDP driver.
> 
> Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>
> Signed-off-by: Bo-Chen Chen <rex-bc.chen@mediatek.com>
> ---
>  drivers/gpu/drm/mediatek/mtk_dp.c | 139
> ++++++++++++++++++++++++++++++
>  1 file changed, 139 insertions(+)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c
> b/drivers/gpu/drm/mediatek/mtk_dp.c
> index e37c9185e4ec..11a94927c0d0 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dp.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dp.c
> @@ -35,6 +35,7 @@
>  
>  #define MTK_DP_SIP_CONTROL_AARCH32	MTK_SIP_SMC_CMD(0x523)
>  #define MTK_DP_SIP_ATF_EDP_VIDEO_UNMUTE	(BIT(0) | BIT(5))
> +#define MTK_DP_SIP_ATF_VIDEO_UNMUTE	BIT(5)
>  
>  #define MTK_DP_THREAD_CABLE_STATE_CHG	BIT(0)
>  #define MTK_DP_THREAD_HPD_EVENT		BIT(1)
> @@ -199,6 +200,89 @@ static const struct mtk_dp_efuse_fmt
> mt8195_edp_efuse_fmt[MTK_DP_CAL_MAX] = {
>  	},
>  };
>  
> +static const struct mtk_dp_efuse_fmt
> mt8195_dp_efuse_fmt[MTK_DP_CAL_MAX] = {
> +	[MTK_DP_CAL_GLB_BIAS_TRIM] = {
> +		.idx = 0,
> +		.shift = 27,
> +		.mask = 0x1f,
> +		.min_val = 1,
> +		.max_val = 0x1e,
> +		.default_val = 0xf,
> +	},
> +	[MTK_DP_CAL_CLKTX_IMPSE] = {
> +		.idx = 0,
> +		.shift = 13,
> +		.mask = 0xf,
> +		.min_val = 1,
> +		.max_val = 0xe,
> +		.default_val = 0x8,
> +	},
> +	[MTK_DP_CAL_LN_TX_IMPSEL_PMOS_0] = {
> +		.idx = 1,
> +		.shift = 28,
> +		.mask = 0xf,
> +		.min_val = 1,
> +		.max_val = 0xe,
> +		.default_val = 0x8,
> +	},
> +	[MTK_DP_CAL_LN_TX_IMPSEL_PMOS_1] = {
> +		.idx = 1,
> +		.shift = 20,
> +		.mask = 0xf,
> +		.min_val = 1,
> +		.max_val = 0xe,
> +		.default_val = 0x8,
> +	},
> +	[MTK_DP_CAL_LN_TX_IMPSEL_PMOS_2] = {
> +		.idx = 1,
> +		.shift = 12,
> +		.mask = 0xf,
> +		.min_val = 1,
> +		.max_val = 0xe,
> +		.default_val = 0x8,
> +	},
> +	[MTK_DP_CAL_LN_TX_IMPSEL_PMOS_3] = {
> +		.idx = 1,
> +		.shift = 4,
> +		.mask = 0xf,
> +		.min_val = 1,
> +		.max_val = 0xe,
> +		.default_val = 0x8,
> +	},
> +	[MTK_DP_CAL_LN_TX_IMPSEL_NMOS_0] = {
> +		.idx = 1,
> +		.shift = 24,
> +		.mask = 0xf,
> +		.min_val = 1,
> +		.max_val = 0xe,
> +		.default_val = 0x8,
> +	},
> +	[MTK_DP_CAL_LN_TX_IMPSEL_NMOS_1] = {
> +		.idx = 1,
> +		.shift = 16,
> +		.mask = 0xf,
> +		.min_val = 1,
> +		.max_val = 0xe,
> +		.default_val = 0x8,
> +	},
> +	[MTK_DP_CAL_LN_TX_IMPSEL_NMOS_2] = {
> +		.idx = 1,
> +		.shift = 8,
> +		.mask = 0xf,
> +		.min_val = 1,
> +		.max_val = 0xe,
> +		.default_val = 0x8,
> +	},
> +	[MTK_DP_CAL_LN_TX_IMPSEL_NMOS_3] = {
> +		.idx = 1,
> +		.shift = 0,
> +		.mask = 0xf,
> +		.min_val = 1,
> +		.max_val = 0xe,
> +		.default_val = 0x8,
> +	},
> +};
> +
>  static struct regmap_config mtk_dp_regmap_config = {
>  	.reg_bits = 32,
>  	.val_bits = 32,
> @@ -1479,6 +1563,50 @@ static int mtk_dp_dt_parse(struct mtk_dp
> *mtk_dp,
>  	return 0;
>  }
>  
> +static enum drm_connector_status mtk_dp_bdg_detect(struct drm_bridge
> *bridge)
> +{
> +	struct mtk_dp *mtk_dp = mtk_dp_from_bridge(bridge);
> +	enum drm_connector_status ret = connector_status_disconnected;
> +	bool enabled = mtk_dp->enabled;
> +	u8 sink_count = 0;
> +
> +	if (mtk_dp->train_info.cable_plugged_in) {

I would modify this as below when I apply this patch into my tree:

if (!mtk_dp->train_info.cable_plugged_in)
	return ret;

Reviewed-by: CK Hu <ck.hu@mediatek.com>


> +		if (!enabled) {
> +			/* power on aux */
> +			mtk_dp_update_bits(mtk_dp,
> MTK_DP_TOP_PWR_STATE,
> +					   DP_PWR_STATE_BANDGAP_TPLL_LA
> NE,
> +					   DP_PWR_STATE_MASK);
> +
> +			/* power on panel */
> +			drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER,
> DP_SET_POWER_D0);
> +			usleep_range(2000, 5000);
> +		}
> +		/*
> +		 * Some dongles still source HPD when they do not
> connect to any
> +		 * sink device. To avoid this, we need to read the sink
> count
> +		 * to make sure we do connect to sink devices. After
> this detect
> +		 * function, we just need to check the HPD connection
> to check
> +		 * whether we connect to a sink device.
> +		 */
> +		drm_dp_dpcd_readb(&mtk_dp->aux, DP_SINK_COUNT,
> &sink_count);
> +		if (DP_GET_SINK_COUNT(sink_count))
> +			ret = connector_status_connected;
> +
> +		if (!enabled) {
> +			/* power off panel */
> +			drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER,
> DP_SET_POWER_D3);
> +			usleep_range(2000, 3000);
> +
> +			/* power off aux */
> +			mtk_dp_update_bits(mtk_dp,
> MTK_DP_TOP_PWR_STATE,
> +					   DP_PWR_STATE_BANDGAP_TPLL,
> +					   DP_PWR_STATE_MASK);
> +		}
> +	}
> +
> +	return ret;
> +}
> +
>  static struct edid *mtk_dp_get_edid(struct drm_bridge *bridge,
>  				    struct drm_connector *connector)
>  {
> @@ -1865,6 +1993,7 @@ static const struct drm_bridge_funcs
> mtk_dp_bridge_funcs = {
>  	.atomic_disable = mtk_dp_bridge_atomic_disable,
>  	.mode_valid = mtk_dp_bridge_mode_valid,
>  	.get_edid = mtk_dp_get_edid,
> +	.detect = mtk_dp_bdg_detect,
>  };
>  
>  static int mtk_dp_probe(struct platform_device *pdev)
> @@ -1991,11 +2120,21 @@ static const struct mtk_dp_data
> mt8195_edp_data = {
>  	.efuse_fmt = mt8195_edp_efuse_fmt,
>  };
>  
> +static const struct mtk_dp_data mt8195_dp_data = {
> +	.bridge_type = DRM_MODE_CONNECTOR_DisplayPort,
> +	.smc_cmd = MTK_DP_SIP_ATF_VIDEO_UNMUTE,
> +	.efuse_fmt = mt8195_dp_efuse_fmt,
> +};
> +
>  static const struct of_device_id mtk_dp_of_match[] = {
>  	{
>  		.compatible = "mediatek,mt8195-edp-tx",
>  		.data = &mt8195_edp_data,
>  	},
> +	{
> +		.compatible = "mediatek,mt8195-dp-tx",
> +		.data = &mt8195_dp_data,
> +	},
>  	{},
>  };
>  MODULE_DEVICE_TABLE(of, mtk_dp_of_match);