usb: host: ohci-exynos: Convert to devm_of_phy_optional_get()

Use the new devm_of_phy_optional_get() helper instead of open-coding the
same operation.

As devm_of_phy_optional_get() returns NULL if either the PHY cannot be
found, or if support for the PHY framework is not enabled, it is no
longer needed to check for -ENODEV or -ENOSYS.

This lets us drop several checks for IS_ERR(), as phy_power_{on,off}()
handle NULL parameters fine.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/3adc5dd1149a17ea7daf4463549feab886c6b145.1674584626.git.geert+renesas@glider.beSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/usb/host/ohci-exynos.c

@@ -69,19 +69,11 @@ static int exynos_ohci_get_phy(struct device *dev,
 			return -EINVAL;
 		}
 
-		phy = devm_of_phy_get(dev, child, NULL);
+		phy = devm_of_phy_optional_get(dev, child, NULL);
 		exynos_ohci->phy[phy_number] = phy;
 		if (IS_ERR(phy)) {
-			ret = PTR_ERR(phy);
-			if (ret == -EPROBE_DEFER) {
-				of_node_put(child);
-				return ret;
-			} else if (ret != -ENOSYS && ret != -ENODEV) {
-				dev_err(dev,
-					"Error retrieving usb2 phy: %d\n", ret);
-				of_node_put(child);
-				return ret;
-			}
+			of_node_put(child);
+			return PTR_ERR(phy);
 		}
 	}
 
@@ -97,12 +89,10 @@ static int exynos_ohci_phy_enable(struct device *dev)
 	int ret = 0;
 
 	for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
-		if (!IS_ERR(exynos_ohci->phy[i]))
-			ret = phy_power_on(exynos_ohci->phy[i]);
+		ret = phy_power_on(exynos_ohci->phy[i]);
 	if (ret)
 		for (i--; i >= 0; i--)
-			if (!IS_ERR(exynos_ohci->phy[i]))
-				phy_power_off(exynos_ohci->phy[i]);
+			phy_power_off(exynos_ohci->phy[i]);
 
 	return ret;
 }
@@ -114,8 +104,7 @@ static void exynos_ohci_phy_disable(struct device *dev)
 	int i;
 
 	for (i = 0; i < PHY_NUMBER; i++)
-		if (!IS_ERR(exynos_ohci->phy[i]))
-			phy_power_off(exynos_ohci->phy[i]);
+		phy_power_off(exynos_ohci->phy[i]);
 }
 
 static int exynos_ohci_probe(struct platform_device *pdev)