usb: ehci-exynos: Change to use phy provided by the generic phy framework

Add the phy provider, supplied by new Exynos-usb2phy using
Generic phy framework.
Keeping the support for older USB phy intact right now, in order
to prevent any functionality break in absence of relevant
device tree side change for ehci-exynos.
Once we move to new phy in the device nodes for ehci, we can
remove the support for older phys.

Signed-off-by: Kamil Debski <[e-mail]>
[[e-mail]: Addressed review comments from mailing list]
[[e-mail]: Kept the code for old usb-phy, and just
added support for new exynos5-usb2phy in generic phy framework]
[[e-mail]: Edited the commit message]
Signed-off-by: Vivek Gautam <[e-mail]>
Cc: Jingoo Han <[e-mail]>
Acked-by: Alan Stern <[e-mail]>
Acked-by: Kukjin Kim <[e-mail]>
Reviewed-by: Tomasz Figa <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

Documentation/devicetree/bindings/usb/exynos-usb.txt

···
  - interrupts: interrupt number to the cpu.
  - clocks: from common clock binding: handle to usb clock.
  - clock-names: from common clock binding: Shall be "usbhost".
+ - port: if in the SoC there are EHCI phys, they should be listed here.
+   One phy per port. Each port should have following entries:
+	- reg: port number on EHCI controller, e.g
+	       On Exynos5250, port 0 is USB2.0 otg phy
+			      port 1 is HSIC phy0
+			      port 2 is HSIC phy1
+	- phys: from the *Generic PHY* bindings; specifying phy used by port.
 
 Optional properties:
  - samsung,vbus-gpio:  if present, specifies the GPIO that
···
 
 		clocks = <&clock 285>;
 		clock-names = "usbhost";
+
+		#address-cells = <1>;
+		#size-cells = <0>;
+		port@0 {
+		    reg = <0>;
+		    phys = <&usb2phy 1>;
+		    status = "disabled";
+		};
 	};
 
 OHCI

drivers/usb/host/ehci-exynos.c

···
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_gpio.h>
+#include <linux/phy/phy.h>
 #include <linux/platform_device.h>
 #include <linux/usb/phy.h>
 #include <linux/usb/samsung_usb_phy.h>
···
 static const char hcd_name[] = "ehci-exynos";
 static struct hc_driver __read_mostly exynos_ehci_hc_driver;
 
+#define PHY_NUMBER 3
+
 struct exynos_ehci_hcd {
 	struct clk *clk;
 	struct usb_phy *phy;
 	struct usb_otg *otg;
+	struct phy *phy_g[PHY_NUMBER];
 };
 
 #define to_exynos_ehci(hcd) (struct exynos_ehci_hcd *)(hcd_to_ehci(hcd)->priv)
+
+static int exynos_ehci_get_phy(struct device *dev,
+				struct exynos_ehci_hcd *exynos_ehci)
+{
+	struct device_node *child;
+	struct phy *phy;
+	int phy_number;
+	int ret = 0;
+
+	exynos_ehci->phy = devm_usb_get_phy(dev, USB_PHY_TYPE_USB2);
+	if (IS_ERR(exynos_ehci->phy)) {
+		ret = PTR_ERR(exynos_ehci->phy);
+		if (ret != -ENXIO && ret != -ENODEV) {
+			dev_err(dev, "no usb2 phy configured\n");
+			return ret;
+		}
+		dev_dbg(dev, "Failed to get usb2 phy\n");
+	} else {
+		exynos_ehci->otg = exynos_ehci->phy->otg;
+	}
+
+	for_each_available_child_of_node(dev->of_node, child) {
+		ret = of_property_read_u32(child, "reg", &phy_number);
+		if (ret) {
+			dev_err(dev, "Failed to parse device tree\n");
+			of_node_put(child);
+			return ret;
+		}
+
+		if (phy_number >= PHY_NUMBER) {
+			dev_err(dev, "Invalid number of PHYs\n");
+			of_node_put(child);
+			return -EINVAL;
+		}
+
+		phy = devm_of_phy_get(dev, child, 0);
+		of_node_put(child);
+		if (IS_ERR(phy)) {
+			ret = PTR_ERR(phy);
+			if (ret != -ENOSYS && ret != -ENODEV) {
+				dev_err(dev, "no usb2 phy configured\n");
+				return ret;
+			}
+			dev_dbg(dev, "Failed to get usb2 phy\n");
+		}
+		exynos_ehci->phy_g[phy_number] = phy;
+	}
+
+	return ret;
+}
+
+static int exynos_ehci_phy_enable(struct device *dev)
+{
+	struct usb_hcd *hcd = dev_get_drvdata(dev);
+	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
+	int i;
+	int ret = 0;
+
+	if (!IS_ERR(exynos_ehci->phy))
+		return usb_phy_init(exynos_ehci->phy);
+
+	for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
+		if (!IS_ERR(exynos_ehci->phy_g[i]))
+			ret = phy_power_on(exynos_ehci->phy_g[i]);
+	if (ret)
+		for (i--; i >= 0; i--)
+			if (!IS_ERR(exynos_ehci->phy_g[i]))
+				phy_power_off(exynos_ehci->phy_g[i]);
+
+	return ret;
+}
+
+static void exynos_ehci_phy_disable(struct device *dev)
+{
+	struct usb_hcd *hcd = dev_get_drvdata(dev);
+	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
+	int i;
+
+	if (!IS_ERR(exynos_ehci->phy)) {
+		usb_phy_shutdown(exynos_ehci->phy);
+		return;
+	}
+
+	for (i = 0; i < PHY_NUMBER; i++)
+		if (!IS_ERR(exynos_ehci->phy_g[i]))
+			phy_power_off(exynos_ehci->phy_g[i]);
+}
 
 static void exynos_setup_vbus_gpio(struct device *dev)
 {
···
 	struct usb_hcd *hcd;
 	struct ehci_hcd *ehci;
 	struct resource *res;
-	struct usb_phy *phy;
 	int irq;
 	int err;
 
···
 					"samsung,exynos5440-ehci"))
 		goto skip_phy;
 
-	phy = devm_usb_get_phy(&pdev->dev, USB_PHY_TYPE_USB2);
-	if (IS_ERR(phy)) {
-		usb_put_hcd(hcd);
-		dev_warn(&pdev->dev, "no platform data or transceiver defined\n");
-		return -EPROBE_DEFER;
-	} else {
-		exynos_ehci->phy = phy;
-		exynos_ehci->otg = phy->otg;
-	}
+	err = exynos_ehci_get_phy(&pdev->dev, exynos_ehci);
+	if (err)
+		goto fail_clk;
 
 skip_phy:
 
···
 	if (exynos_ehci->otg)
 		exynos_ehci->otg->set_host(exynos_ehci->otg, &hcd->self);
 
-	if (exynos_ehci->phy)
-		usb_phy_init(exynos_ehci->phy);
+	err = exynos_ehci_phy_enable(&pdev->dev);
+	if (err) {
+		dev_err(&pdev->dev, "Failed to enable USB phy\n");
+		goto fail_io;
+	}
 
 	ehci = hcd_to_ehci(hcd);
 	ehci->caps = hcd->regs;
···
 	return 0;
 
 fail_add_hcd:
-	if (exynos_ehci->phy)
-		usb_phy_shutdown(exynos_ehci->phy);
+	exynos_ehci_phy_disable(&pdev->dev);
 fail_io:
 	clk_disable_unprepare(exynos_ehci->clk);
 fail_clk:
···
 	if (exynos_ehci->otg)
 		exynos_ehci->otg->set_host(exynos_ehci->otg, &hcd->self);
 
-	if (exynos_ehci->phy)
-		usb_phy_shutdown(exynos_ehci->phy);
+	exynos_ehci_phy_disable(&pdev->dev);
 
 	clk_disable_unprepare(exynos_ehci->clk);
 
···
 	if (exynos_ehci->otg)
 		exynos_ehci->otg->set_host(exynos_ehci->otg, &hcd->self);
 
-	if (exynos_ehci->phy)
-		usb_phy_shutdown(exynos_ehci->phy);
+	exynos_ehci_phy_disable(dev);
 
 	clk_disable_unprepare(exynos_ehci->clk);
 
···
 {
 	struct usb_hcd *hcd = dev_get_drvdata(dev);
 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
+	int ret;
 
 	clk_prepare_enable(exynos_ehci->clk);
 
 	if (exynos_ehci->otg)
 		exynos_ehci->otg->set_host(exynos_ehci->otg, &hcd->self);
 
-	if (exynos_ehci->phy)
-		usb_phy_init(exynos_ehci->phy);
+	ret = exynos_ehci_phy_enable(dev);
+	if (ret) {
+		dev_err(dev, "Failed to enable USB phy\n");
+		clk_disable_unprepare(exynos_ehci->clk);
+		return ret;
+	}
 
 	/* DMA burst Enable */
 	writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));