phy: bcm-ns-usb3: use pointer for PHY writing function

Our current writing function accesses PHY directly bypassing MDIO layer.

The aim is to extend this module to also behave as MDIO driver. This
will require using different writing function which can be handled
cleanly by having an extra pointer like this.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

drivers/phy/broadcom/phy-bcm-ns-usb3.c

@@ -53,6 +53,8 @@ struct bcm_ns_usb3 {
 	void __iomem *dmp;
 	void __iomem *ccb_mii;
 	struct phy *phy;
+
+	int (*phy_write)(struct bcm_ns_usb3 *usb3, u16 reg, u16 value);
 };
 
 static const struct of_device_id bcm_ns_usb3_id_table[] = {
@@ -68,51 +70,10 @@ static const struct of_device_id bcm_ns_usb3_id_table[] = {
 };
 MODULE_DEVICE_TABLE(of, bcm_ns_usb3_id_table);
 
-static int bcm_ns_usb3_wait_reg(struct bcm_ns_usb3 *usb3, void __iomem *addr,
-				u32 mask, u32 value, unsigned long timeout)
-{
-	unsigned long deadline = jiffies + timeout;
-	u32 val;
-
-	do {
-		val = readl(addr);
-		if ((val & mask) == value)
-			return 0;
-		cpu_relax();
-		udelay(10);
-	} while (!time_after_eq(jiffies, deadline));
-
-	dev_err(usb3->dev, "Timeout waiting for register %p\n", addr);
-
-	return -EBUSY;
-}
-
-static inline int bcm_ns_usb3_mii_mng_wait_idle(struct bcm_ns_usb3 *usb3)
-{
-	return bcm_ns_usb3_wait_reg(usb3, usb3->ccb_mii + BCMA_CCB_MII_MNG_CTL,
-				    0x0100, 0x0000,
-				    usecs_to_jiffies(BCM_NS_USB3_MII_MNG_TIMEOUT_US));
-}
-
 static int bcm_ns_usb3_mdio_phy_write(struct bcm_ns_usb3 *usb3, u16 reg,
 				      u16 value)
 {
-	u32 tmp = 0;
-	int err;
-
-	err = bcm_ns_usb3_mii_mng_wait_idle(usb3);
-	if (err < 0) {
-		dev_err(usb3->dev, "Couldn't write 0x%08x value\n", value);
-		return err;
-	}
-
-	/* TODO: Use a proper MDIO bus layer */
-	tmp |= 0x58020000; /* Magic value for MDIO PHY write */
-	tmp |= reg << 18;
-	tmp |= value;
-	writel(tmp, usb3->ccb_mii + BCMA_CCB_MII_MNG_CMD_DATA);
-
-	return bcm_ns_usb3_mii_mng_wait_idle(usb3);
+	return usb3->phy_write(usb3, reg, value);
 }
 
 static int bcm_ns_usb3_phy_init_ns_bx(struct bcm_ns_usb3 *usb3)
@@ -233,6 +194,57 @@ static const struct phy_ops ops = {
 	.owner		= THIS_MODULE,
 };
 
+/**************************************************
+ * Platform driver code
+ **************************************************/
+
+static int bcm_ns_usb3_wait_reg(struct bcm_ns_usb3 *usb3, void __iomem *addr,
+				u32 mask, u32 value, unsigned long timeout)
+{
+	unsigned long deadline = jiffies + timeout;
+	u32 val;
+
+	do {
+		val = readl(addr);
+		if ((val & mask) == value)
+			return 0;
+		cpu_relax();
+		udelay(10);
+	} while (!time_after_eq(jiffies, deadline));
+
+	dev_err(usb3->dev, "Timeout waiting for register %p\n", addr);
+
+	return -EBUSY;
+}
+
+static inline int bcm_ns_usb3_mii_mng_wait_idle(struct bcm_ns_usb3 *usb3)
+{
+	return bcm_ns_usb3_wait_reg(usb3, usb3->ccb_mii + BCMA_CCB_MII_MNG_CTL,
+				    0x0100, 0x0000,
+				    usecs_to_jiffies(BCM_NS_USB3_MII_MNG_TIMEOUT_US));
+}
+
+static int bcm_ns_usb3_platform_phy_write(struct bcm_ns_usb3 *usb3, u16 reg,
+					  u16 value)
+{
+	u32 tmp = 0;
+	int err;
+
+	err = bcm_ns_usb3_mii_mng_wait_idle(usb3);
+	if (err < 0) {
+		dev_err(usb3->dev, "Couldn't write 0x%08x value\n", value);
+		return err;
+	}
+
+	/* TODO: Use a proper MDIO bus layer */
+	tmp |= 0x58020000; /* Magic value for MDIO PHY write */
+	tmp |= reg << 18;
+	tmp |= value;
+	writel(tmp, usb3->ccb_mii + BCMA_CCB_MII_MNG_CMD_DATA);
+
+	return bcm_ns_usb3_mii_mng_wait_idle(usb3);
+}
+
 static int bcm_ns_usb3_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -266,6 +278,8 @@ static int bcm_ns_usb3_probe(struct platform_device *pdev)
 		return PTR_ERR(usb3->ccb_mii);
 	}
 
+	usb3->phy_write = bcm_ns_usb3_platform_phy_write;
+
 	usb3->phy = devm_phy_create(dev, NULL, &ops);
 	if (IS_ERR(usb3->phy)) {
 		dev_err(dev, "Failed to create PHY\n");