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  3. [PATCH v3 0/2] phy: qcom: edp: Add DP/eDP switch for phys
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[PATCH v3 2/2] phy: qcom: edp: Add per-version LDO configuration callback

Yongxing Mou posted 2 patches 1 month ago
[PATCH v3 2/2] phy: qcom: edp: Add per-version LDO configuration callback
Posted by Yongxing Mou 1 month ago 
For eDP low Vdiff, the LDO setting depends on the PHY version, instead of
being a simple 0x0 or 0x01. Introduce the com_ldo_config callback to
correct LDO setting accroding to the HPG.

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

Cc: stable@vger.kernel.org
Fixes: f199223cb490 ("phy: qcom: Introduce new eDP PHY driver")
Signed-off-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com>
---
 drivers/phy/qualcomm/phy-qcom-edp.c | 86 ++++++++++++++++++++++++++++++++-----
 1 file changed, 76 insertions(+), 10 deletions(-)

diff --git a/drivers/phy/qualcomm/phy-qcom-edp.c b/drivers/phy/qualcomm/phy-qcom-edp.c
index 36998326bae6..d29e548fce9d 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 {
@@ -304,7 +305,7 @@ 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;
@@ -330,13 +331,13 @@ 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);
 
@@ -560,6 +561,52 @@ 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,
@@ -567,6 +614,7 @@ 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 = {
@@ -583,7 +631,7 @@ 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 sc8280xp_dp_phy_cfg = {
@@ -768,6 +816,24 @@ 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,
@@ -775,6 +841,7 @@ 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 = {
@@ -955,6 +1022,7 @@ 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 = {
@@ -970,7 +1038,6 @@ 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;
@@ -979,11 +1046,10 @@ static int qcom_edp_phy_power_on(struct phy *phy)
 	if (ret)
 		return ret;
 
-	if (edp->cfg->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
Re: [PATCH v3 2/2] phy: qcom: edp: Add per-version LDO configuration callback
Posted by Dmitry Baryshkov 1 week, 5 days ago 
On Mon, Mar 02, 2026 at 04:28:30PM +0800, Yongxing Mou wrote:
> For eDP low Vdiff, the LDO setting depends on the PHY version, instead of
> being a simple 0x0 or 0x01. Introduce the com_ldo_config callback to
> correct LDO setting accroding to the HPG.
> 
> Since SC7280 uses different LDO settings than SA8775P/SC8280XP, introduce
> qcom_edp_phy_ops_v3 to keep the LDO setting correct.

Please mention that this also uses low vdiff for eDP.

With that in place:


Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>


> 
> Cc: stable@vger.kernel.org
> Fixes: f199223cb490 ("phy: qcom: Introduce new eDP PHY driver")
> Signed-off-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com>
> ---
>  drivers/phy/qualcomm/phy-qcom-edp.c | 86 ++++++++++++++++++++++++++++++++-----
>  1 file changed, 76 insertions(+), 10 deletions(-)

-- 
With best wishes
Dmitry
Re: [PATCH v3 2/2] phy: qcom: edp: Add per-version LDO configuration callback
Posted by Konrad Dybcio 3 weeks, 6 days ago 
On 3/2/26 9:28 AM, Yongxing Mou wrote:
> For eDP low Vdiff, the LDO setting depends on the PHY version, instead of
> being a simple 0x0 or 0x01. Introduce the com_ldo_config callback to
> correct LDO setting accroding to the HPG.
> 
> Since SC7280 uses different LDO settings than SA8775P/SC8280XP, introduce
> qcom_edp_phy_ops_v3 to keep the LDO setting correct.
> 
> Cc: stable@vger.kernel.org
> Fixes: f199223cb490 ("phy: qcom: Introduce new eDP PHY driver")
> Signed-off-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com>
> ---

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Tested-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> # SC8280XP X13s

Konrad

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