usb: dwc3: exynos: Make provision for vdd regulators

Facilitate getting required 3.3V and 1.0V VDD supply for
DWC3 controller on Exynos.

With patches for regulators' nodes merged in 3.15:
c8c253f ARM: dts: Add regulator entries to smdk5420
275dcd2 ARM: dts: add max77686 pmic node for smdk5250,

certain perripherals will now need to ensure that,
they request VDD regulators in their drivers, and enable
them so as to make them working.

Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
Cc: Anton Tikhomirov <av.tikhomirov@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/dwc3/dwc3-exynos.c

@@ -27,6 +27,7 @@
 #include <linux/usb/usb_phy_generic.h>
 #include <linux/of.h>
 #include <linux/of_platform.h>
+#include <linux/regulator/consumer.h>
 
 struct dwc3_exynos {
 	struct platform_device	*usb2_phy;
@@ -34,6 +35,8 @@ struct dwc3_exynos {
 	struct device		*dev;
 
 	struct clk		*clk;
+	struct regulator	*vdd33;
+	struct regulator	*vdd10;
 };
 
 static int dwc3_exynos_register_phys(struct dwc3_exynos *exynos)
@@ -144,20 +147,46 @@ static int dwc3_exynos_probe(struct platform_device *pdev)
 
 	clk_prepare_enable(exynos->clk);
 
+	exynos->vdd33 = devm_regulator_get(dev, "vdd33");
+	if (IS_ERR(exynos->vdd33)) {
+		ret = PTR_ERR(exynos->vdd33);
+		goto err2;
+	}
+	ret = regulator_enable(exynos->vdd33);
+	if (ret) {
+		dev_err(dev, "Failed to enable VDD33 supply\n");
+		goto err2;
+	}
+
+	exynos->vdd10 = devm_regulator_get(dev, "vdd10");
+	if (IS_ERR(exynos->vdd10)) {
+		ret = PTR_ERR(exynos->vdd10);
+		goto err3;
+	}
+	ret = regulator_enable(exynos->vdd10);
+	if (ret) {
+		dev_err(dev, "Failed to enable VDD10 supply\n");
+		goto err3;
+	}
+
 	if (node) {
 		ret = of_platform_populate(node, NULL, NULL, dev);
 		if (ret) {
 			dev_err(dev, "failed to add dwc3 core\n");
-			goto err2;
+			goto err4;
 		}
 	} else {
 		dev_err(dev, "no device node, failed to add dwc3 core\n");
 		ret = -ENODEV;
-		goto err2;
+		goto err4;
 	}
 
 	return 0;
 
+err4:
+	regulator_disable(exynos->vdd10);
+err3:
+	regulator_disable(exynos->vdd33);
 err2:
 	clk_disable_unprepare(clk);
 err1:
@@ -174,6 +203,9 @@ static int dwc3_exynos_remove(struct platform_device *pdev)
 
 	clk_disable_unprepare(exynos->clk);
 
+	regulator_disable(exynos->vdd33);
+	regulator_disable(exynos->vdd10);
+
 	return 0;
 }
 
@@ -192,12 +224,27 @@ static int dwc3_exynos_suspend(struct device *dev)
 
 	clk_disable(exynos->clk);
 
+	regulator_disable(exynos->vdd33);
+	regulator_disable(exynos->vdd10);
+
 	return 0;
 }
 
 static int dwc3_exynos_resume(struct device *dev)
 {
 	struct dwc3_exynos *exynos = dev_get_drvdata(dev);
+	int ret;
+
+	ret = regulator_enable(exynos->vdd33);
+	if (ret) {
+		dev_err(dev, "Failed to enable VDD33 supply\n");
+		return ret;
+	}
+	ret = regulator_enable(exynos->vdd10);
+	if (ret) {
+		dev_err(dev, "Failed to enable VDD10 supply\n");
+		return ret;
+	}
 
 	clk_enable(exynos->clk);