diff --git a/drivers/phy/phy-sun4i-usb.c b/drivers/phy/phy-sun4i-usb.c
index 03f030b491d6..b9342a2af7b3 100644
--- a/drivers/phy/phy-sun4i-usb.c
+++ b/drivers/phy/phy-sun4i-usb.c
@@ -40,6 +40,7 @@
 #include <linux/power_supply.h>
 #include <linux/regulator/consumer.h>
 #include <linux/reset.h>
+#include <linux/spinlock.h>
 #include <linux/usb/of.h>
 #include <linux/workqueue.h>
 
@@ -114,7 +115,7 @@ struct sun4i_usb_phy_data {
 	void __iomem *base;
 	const struct sun4i_usb_phy_cfg *cfg;
 	enum usb_dr_mode dr_mode;
-	struct mutex mutex;
+	spinlock_t reg_lock; /* guard access to phyctl reg */
 	struct sun4i_usb_phy {
 		struct phy *phy;
 		void __iomem *pmu;
@@ -181,9 +182,10 @@ static void sun4i_usb_phy_write(struct sun4i_usb_phy *phy, u32 addr, u32 data,
 	struct sun4i_usb_phy_data *phy_data = to_sun4i_usb_phy_data(phy);
 	u32 temp, usbc_bit = BIT(phy->index * 2);
 	void __iomem *phyctl = phy_data->base + phy_data->cfg->phyctl_offset;
+	unsigned long flags;
 	int i;
 
-	mutex_lock(&phy_data->mutex);
+	spin_lock_irqsave(&phy_data->reg_lock, flags);
 
 	if (phy_data->cfg->type == sun8i_a33_phy ||
 	    phy_data->cfg->type == sun50i_a64_phy) {
@@ -221,7 +223,8 @@ static void sun4i_usb_phy_write(struct sun4i_usb_phy *phy, u32 addr, u32 data,
 
 		data >>= 1;
 	}
-	mutex_unlock(&phy_data->mutex);
+
+	spin_unlock_irqrestore(&phy_data->reg_lock, flags);
 }
 
 static void sun4i_usb_phy_passby(struct sun4i_usb_phy *phy, int enable)
@@ -615,7 +618,7 @@ static int sun4i_usb_phy_probe(struct platform_device *pdev)
 	if (!data)
 		return -ENOMEM;
 
-	mutex_init(&data->mutex);
+	spin_lock_init(&data->reg_lock);
 	INIT_DELAYED_WORK(&data->detect, sun4i_usb_phy0_id_vbus_det_scan);
 	dev_set_drvdata(dev, data);
 	data->cfg = of_device_get_match_data(dev);