usb: phy: mxs: enable regulator phy-3p0 to improve signal qualilty

Enable regulator 'phy-3p0' to pass eye diagram test since it improve signal
qualilty.

Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Reviewed-by: Peter Chen <peter.chen@kernel.org>
Link: https://lore.kernel.org/r/20240726113207.3393247-1-xu.yang_2@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/phy/phy-mxs-usb.c b/drivers/usb/phy/phy-mxs-usb.c
index 920a32cd094d6f48faf145a6a5e74bb817dfdf89..d9d29f0b37de93aa90fa03d8c03033dc4109d361 100644 (file)
--- a/drivers/usb/phy/phy-mxs-usb.c
+++ b/drivers/usb/phy/phy-mxs-usb.c
@@ -18,6 +18,7 @@
 #include <linux/regmap.h>
 #include <linux/mfd/syscon.h>
 #include <linux/iopoll.h>
+#include <linux/regulator/consumer.h>
 
 #define DRIVER_NAME "mxs_phy"
 
@@ -204,6 +205,7 @@ struct mxs_phy {
        int port_id;
        u32 tx_reg_set;
        u32 tx_reg_mask;
+       struct regulator *phy_3p0;
 };
 
 static inline bool is_imx6q_phy(struct mxs_phy *mxs_phy)
@@ -288,6 +290,16 @@ static int mxs_phy_hw_init(struct mxs_phy *mxs_phy)
        if (ret)
                goto disable_pll;
 
+       if (mxs_phy->phy_3p0) {
+               ret = regulator_enable(mxs_phy->phy_3p0);
+               if (ret) {
+                       dev_err(mxs_phy->phy.dev,
+                               "Failed to enable 3p0 regulator, ret=%d\n",
+                               ret);
+                       return ret;
+               }
+       }
+
        /* Power up the PHY */
        writel(0, base + HW_USBPHY_PWD);
 
@@ -448,6 +460,9 @@ static void mxs_phy_shutdown(struct usb_phy *phy)
        if (is_imx7ulp_phy(mxs_phy))
                mxs_phy_pll_enable(phy->io_priv, false);
 
+       if (mxs_phy->phy_3p0)
+               regulator_disable(mxs_phy->phy_3p0);
+
        clk_disable_unprepare(mxs_phy->clk);
 }
 
@@ -789,6 +804,17 @@ static int mxs_phy_probe(struct platform_device *pdev)
        mxs_phy->clk = clk;
        mxs_phy->data = of_device_get_match_data(&pdev->dev);
 
+       mxs_phy->phy_3p0 = devm_regulator_get(&pdev->dev, "phy-3p0");
+       if (PTR_ERR(mxs_phy->phy_3p0) == -ENODEV)
+               /* not exist */
+               mxs_phy->phy_3p0 = NULL;
+       else if (IS_ERR(mxs_phy->phy_3p0))
+               return dev_err_probe(&pdev->dev, PTR_ERR(mxs_phy->phy_3p0),
+                               "Getting regulator error\n");
+
+       if (mxs_phy->phy_3p0)
+               regulator_set_voltage(mxs_phy->phy_3p0, 3200000, 3200000);
+
        platform_set_drvdata(pdev, mxs_phy);
 
        device_set_wakeup_capable(&pdev->dev, true);