[PATCH v4 5/5] phy: qcom: edp: Add PHY-specific LDO config for eDP low vdiff

Yongxing Mou yongxing.mou at oss.qualcomm.com
Tue Apr 21 23:01:55 PDT 2026


For eDP low vdiff, the LDO setting depends on the PHY version rather
than being a simple 0x0 or 0x1 value. Introduce a PHY callback to program
the correct LDO setting according to the HPG.

Since SC7280/SC8180X uses different LDO settings from SA8775P/SC8280XP,
introduce qcom_edp_phy_ops_v3 to keep the LDO setting correct.

Cc: stable at vger.kernel.org
Fixes: f199223cb490 ("phy: qcom: Introduce new eDP PHY driver")
Signed-off-by: Yongxing Mou <yongxing.mou at oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov at oss.qualcomm.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio at oss.qualcomm.com>
Tested-by: Konrad Dybcio <konrad.dybcio at oss.qualcomm.com> # SC8280XP X13s
---
 drivers/phy/qualcomm/phy-qcom-edp.c | 88 ++++++++++++++++++++++++++++++++-----
 1 file changed, 77 insertions(+), 11 deletions(-)

diff --git a/drivers/phy/qualcomm/phy-qcom-edp.c b/drivers/phy/qualcomm/phy-qcom-edp.c
index bbd45f709a4b..3a5284522bab 100644
--- a/drivers/phy/qualcomm/phy-qcom-edp.c
+++ b/drivers/phy/qualcomm/phy-qcom-edp.c
@@ -81,6 +81,7 @@ struct phy_ver_ops {
 	int (*com_clk_fwd_cfg)(const struct qcom_edp *edp);
 	int (*com_configure_pll)(const struct qcom_edp *edp);
 	int (*com_configure_ssc)(const struct qcom_edp *edp);
+	int (*com_ldo_config)(const struct qcom_edp *edp);
 };
 
 struct qcom_edp_phy_cfg {
@@ -339,7 +340,7 @@ static int qcom_edp_set_voltages(struct qcom_edp *edp, const struct phy_configur
 	const struct qcom_edp_swing_pre_emph_cfg *cfg;
 	unsigned int v_level = 0;
 	unsigned int p_level = 0;
-	u8 ldo_config;
+	int ret;
 	u8 swing;
 	u8 emph;
 	int i;
@@ -365,13 +366,13 @@ static int qcom_edp_set_voltages(struct qcom_edp *edp, const struct phy_configur
 	if (swing == 0xff || emph == 0xff)
 		return -EINVAL;
 
-	ldo_config = edp->is_edp ? 0x0 : 0x1;
+	ret = edp->cfg->ver_ops->com_ldo_config(edp);
+	if (ret)
+		return ret;
 
-	writel(ldo_config, edp->tx0 + TXn_LDO_CONFIG);
 	writel(swing, edp->tx0 + TXn_TX_DRV_LVL);
 	writel(emph, edp->tx0 + TXn_TX_EMP_POST1_LVL);
 
-	writel(ldo_config, edp->tx1 + TXn_LDO_CONFIG);
 	writel(swing, edp->tx1 + TXn_TX_DRV_LVL);
 	writel(emph, edp->tx1 + TXn_TX_EMP_POST1_LVL);
 
@@ -595,6 +596,52 @@ static int qcom_edp_com_configure_pll_v4(const struct qcom_edp *edp)
 	return 0;
 }
 
+static int qcom_edp_ldo_config_v3(const struct qcom_edp *edp)
+{
+	const struct phy_configure_opts_dp *dp_opts = &edp->dp_opts;
+	u32 ldo_config;
+
+	if (!edp->is_edp)
+		ldo_config = 0x0;
+	else if (dp_opts->link_rate <= 2700)
+		ldo_config = 0x81;
+	else
+		ldo_config = 0x41;
+
+	writel(ldo_config, edp->tx0 + TXn_LDO_CONFIG);
+	writel(dp_opts->lanes > 2 ? ldo_config : 0x00, edp->tx1 + TXn_LDO_CONFIG);
+
+	return 0;
+}
+
+static int qcom_edp_ldo_config_v4(const struct qcom_edp *edp)
+{
+	const struct phy_configure_opts_dp *dp_opts = &edp->dp_opts;
+	u32 ldo_config;
+
+	if (!edp->is_edp)
+		ldo_config = 0x0;
+	else if (dp_opts->link_rate <= 2700)
+		ldo_config = 0xc1;
+	else
+		ldo_config = 0x81;
+
+	writel(ldo_config, edp->tx0 + TXn_LDO_CONFIG);
+	writel(dp_opts->lanes > 2 ? ldo_config : 0x00, edp->tx1 + TXn_LDO_CONFIG);
+
+	return 0;
+}
+
+static const struct phy_ver_ops qcom_edp_phy_ops_v3 = {
+	.com_power_on		= qcom_edp_phy_power_on_v4,
+	.com_resetsm_cntrl	= qcom_edp_phy_com_resetsm_cntrl_v4,
+	.com_bias_en_clkbuflr	= qcom_edp_com_bias_en_clkbuflr_v4,
+	.com_clk_fwd_cfg	= qcom_edp_com_clk_fwd_cfg_v4,
+	.com_configure_pll	= qcom_edp_com_configure_pll_v4,
+	.com_configure_ssc	= qcom_edp_com_configure_ssc_v4,
+	.com_ldo_config		= qcom_edp_ldo_config_v3,
+};
+
 static const struct phy_ver_ops qcom_edp_phy_ops_v4 = {
 	.com_power_on		= qcom_edp_phy_power_on_v4,
 	.com_resetsm_cntrl	= qcom_edp_phy_com_resetsm_cntrl_v4,
@@ -602,6 +649,7 @@ static const struct phy_ver_ops qcom_edp_phy_ops_v4 = {
 	.com_clk_fwd_cfg	= qcom_edp_com_clk_fwd_cfg_v4,
 	.com_configure_pll	= qcom_edp_com_configure_pll_v4,
 	.com_configure_ssc	= qcom_edp_com_configure_ssc_v4,
+	.com_ldo_config		= qcom_edp_ldo_config_v4,
 };
 
 static const struct qcom_edp_phy_cfg sa8775p_dp_phy_cfg = {
@@ -618,7 +666,7 @@ static const struct qcom_edp_phy_cfg sc7280_dp_phy_cfg = {
 	.vco_div_cfg = edp_phy_vco_div_cfg_v4,
 	.dp_swing_pre_emph_cfg = &dp_phy_swing_pre_emph_cfg,
 	.edp_swing_pre_emph_cfg = &edp_phy_swing_pre_emph_cfg_v3,
-	.ver_ops = &qcom_edp_phy_ops_v4,
+	.ver_ops = &qcom_edp_phy_ops_v3,
 };
 
 static const struct qcom_edp_phy_cfg sc8180x_dp_phy_cfg = {
@@ -626,7 +674,7 @@ static const struct qcom_edp_phy_cfg sc8180x_dp_phy_cfg = {
 	.vco_div_cfg = edp_phy_vco_div_cfg_v4,
 	.dp_swing_pre_emph_cfg = &dp_phy_swing_pre_emph_cfg_v2,
 	.edp_swing_pre_emph_cfg = &edp_phy_swing_pre_emph_cfg_v2,
-	.ver_ops = &qcom_edp_phy_ops_v4,
+	.ver_ops = &qcom_edp_phy_ops_v3,
 };
 
 static const struct qcom_edp_phy_cfg sc8280xp_dp_phy_cfg = {
@@ -811,6 +859,24 @@ static int qcom_edp_com_configure_pll_v6(const struct qcom_edp *edp)
 	return 0;
 }
 
+static int qcom_edp_ldo_config_v6(const struct qcom_edp *edp)
+{
+	const struct phy_configure_opts_dp *dp_opts = &edp->dp_opts;
+	u32 ldo_config;
+
+	if (!edp->is_edp)
+		ldo_config = 0x0;
+	else if (dp_opts->link_rate <= 2700)
+		ldo_config = 0x51;
+	else
+		ldo_config = 0x91;
+
+	writel(ldo_config, edp->tx0 + TXn_LDO_CONFIG);
+	writel(dp_opts->lanes > 2 ? ldo_config : 0x00, edp->tx1 + TXn_LDO_CONFIG);
+
+	return 0;
+}
+
 static const struct phy_ver_ops qcom_edp_phy_ops_v6 = {
 	.com_power_on		= qcom_edp_phy_power_on_v6,
 	.com_resetsm_cntrl	= qcom_edp_phy_com_resetsm_cntrl_v6,
@@ -818,6 +884,7 @@ static const struct phy_ver_ops qcom_edp_phy_ops_v6 = {
 	.com_clk_fwd_cfg	= qcom_edp_com_clk_fwd_cfg_v4,
 	.com_configure_pll	= qcom_edp_com_configure_pll_v6,
 	.com_configure_ssc	= qcom_edp_com_configure_ssc_v6,
+	.com_ldo_config		= qcom_edp_ldo_config_v6,
 };
 
 static struct qcom_edp_phy_cfg x1e80100_phy_cfg = {
@@ -998,6 +1065,7 @@ static const struct phy_ver_ops qcom_edp_phy_ops_v8 = {
 	.com_clk_fwd_cfg	= qcom_edp_com_clk_fwd_cfg_v8,
 	.com_configure_pll	= qcom_edp_com_configure_pll_v8,
 	.com_configure_ssc	= qcom_edp_com_configure_ssc_v8,
+	.com_ldo_config		= qcom_edp_ldo_config_v6,
 };
 
 static struct qcom_edp_phy_cfg glymur_phy_cfg = {
@@ -1013,7 +1081,6 @@ static int qcom_edp_phy_power_on(struct phy *phy)
 	const struct qcom_edp *edp = phy_get_drvdata(phy);
 	u32 bias0_en, drvr0_en, bias1_en, drvr1_en;
 	unsigned long pixel_freq;
-	u8 ldo_config = 0x0;
 	int ret;
 	u32 val;
 	u8 cfg1;
@@ -1022,11 +1089,10 @@ static int qcom_edp_phy_power_on(struct phy *phy)
 	if (ret)
 		return ret;
 
-	if (edp->cfg->edp_swing_pre_emph_cfg && !edp->is_edp)
-		ldo_config = 0x1;
+	ret = edp->cfg->ver_ops->com_ldo_config(edp);
+	if (ret)
+		return ret;
 
-	writel(ldo_config, edp->tx0 + TXn_LDO_CONFIG);
-	writel(ldo_config, edp->tx1 + TXn_LDO_CONFIG);
 	writel(0x00, edp->tx0 + TXn_LANE_MODE_1);
 	writel(0x00, edp->tx1 + TXn_LANE_MODE_1);
 

-- 
2.43.0




More information about the linux-phy mailing list