usb: ohci-exynos: Add facility to use phy provided by the generic phy framework

Add support to consume phy provided by 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 ohci-exynos.
Once we move to new phy in the device nodes for ohci, we can
remove the support for older phys.

Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/devicetree/bindings/usb/exynos-usb.txt b/Documentation/devicetree/bindings/usb/exynos-usb.txt
index d967ba1..49a9c6f 100644 (file)
--- a/Documentation/devicetree/bindings/usb/exynos-usb.txt
+++ b/Documentation/devicetree/bindings/usb/exynos-usb.txt
@@ -38,6 +38,13 @@ Required properties:
  - 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 OHCI phys, they should be listed here.
+   One phy per port. Each port should have following entries:
+       - reg: port number on OHCI 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.
 
 Example:
        usb@12120000 {
@@ -47,6 +54,15 @@ Example:
 
                clocks = <&clock 285>;
                clock-names = "usbhost";
+
+               #address-cells = <1>;
+               #size-cells = <0>;
+               port@0 {
+                   reg = <0>;
+                   phys = <&usb2phy 1>;
+                   status = "disabled";
+               };
+
        };
 
 DWC3

diff --git a/drivers/usb/host/ohci-exynos.c b/drivers/usb/host/ohci-exynos.c
index 05f00e3..32f2ff1 100644 (file)
--- a/drivers/usb/host/ohci-exynos.c
+++ b/drivers/usb/host/ohci-exynos.c
@@ -18,6 +18,7 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/phy/phy.h>
 #include <linux/usb/phy.h>
 #include <linux/usb/samsung_usb_phy.h>
 #include <linux/usb.h>
@@ -33,28 +34,110 @@ static struct hc_driver __read_mostly exynos_ohci_hc_driver;
 
 #define to_exynos_ohci(hcd) (struct exynos_ohci_hcd *)(hcd_to_ohci(hcd)->priv)
 
+#define PHY_NUMBER 3
+
 struct exynos_ohci_hcd {
        struct clk *clk;
        struct usb_phy *phy;
        struct usb_otg *otg;
+       struct phy *phy_g[PHY_NUMBER];
 };
 
-static void exynos_ohci_phy_enable(struct device *dev)
+static int exynos_ohci_get_phy(struct device *dev,
+                               struct exynos_ohci_hcd *exynos_ohci)
+{
+       struct device_node *child;
+       struct phy *phy;
+       int phy_number;
+       int ret = 0;
+
+       exynos_ohci->phy = devm_usb_get_phy(dev, USB_PHY_TYPE_USB2);
+       if (IS_ERR(exynos_ohci->phy)) {
+               ret = PTR_ERR(exynos_ohci->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_ohci->otg = exynos_ohci->phy->otg;
+       }
+
+       /*
+        * Getting generic phy:
+        * We are keeping both types of phys as a part of transiting OHCI
+        * to generic phy framework, so as to maintain backward compatibilty
+        * with old DTB.
+        * If there are existing devices using DTB files built from them,
+        * to remove the support for old bindings in this driver,
+        * we need to make sure that such devices have their DTBs
+        * updated to ones built from new DTS.
+        */
+       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_ohci->phy_g[phy_number] = phy;
+       }
+
+       return ret;
+}
+
+static int exynos_ohci_phy_enable(struct device *dev)
 {
        struct usb_hcd *hcd = dev_get_drvdata(dev);
        struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
+       int i;
+       int ret = 0;
+
+       if (!IS_ERR(exynos_ohci->phy))
+               return usb_phy_init(exynos_ohci->phy);
 
-       if (exynos_ohci->phy)
-               usb_phy_init(exynos_ohci->phy);
+       for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
+               if (!IS_ERR(exynos_ohci->phy_g[i]))
+                       ret = phy_power_on(exynos_ohci->phy_g[i]);
+       if (ret)
+               for (i--; i >= 0; i--)
+                       if (!IS_ERR(exynos_ohci->phy_g[i]))
+                               phy_power_off(exynos_ohci->phy_g[i]);
+
+       return ret;
 }
 
 static void exynos_ohci_phy_disable(struct device *dev)
 {
        struct usb_hcd *hcd = dev_get_drvdata(dev);
        struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
+       int i;
 
-       if (exynos_ohci->phy)
+       if (!IS_ERR(exynos_ohci->phy)) {
                usb_phy_shutdown(exynos_ohci->phy);
+               return;
+       }
+
+       for (i = 0; i < PHY_NUMBER; i++)
+               if (!IS_ERR(exynos_ohci->phy_g[i]))
+                       phy_power_off(exynos_ohci->phy_g[i]);
 }
 
 static int exynos_ohci_probe(struct platform_device *pdev)
@@ -62,7 +145,6 @@ static int exynos_ohci_probe(struct platform_device *pdev)
        struct exynos_ohci_hcd *exynos_ohci;
        struct usb_hcd *hcd;
        struct resource *res;
-       struct usb_phy *phy;
        int irq;
        int err;
 
@@ -88,15 +170,9 @@ static int exynos_ohci_probe(struct platform_device *pdev)
                                        "samsung,exynos5440-ohci"))
                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_ohci->phy = phy;
-               exynos_ohci->otg = phy->otg;
-       }
+       err = exynos_ohci_get_phy(&pdev->dev, exynos_ohci);
+       if (err)
+               goto fail_clk;
 
 skip_phy:
        exynos_ohci->clk = devm_clk_get(&pdev->dev, "usbhost");
@@ -139,7 +215,11 @@ skip_phy:
 
        platform_set_drvdata(pdev, hcd);
 
-       exynos_ohci_phy_enable(&pdev->dev);
+       err = exynos_ohci_phy_enable(&pdev->dev);
+       if (err) {
+               dev_err(&pdev->dev, "Failed to enable USB phy\n");
+               goto fail_io;
+       }
 
        err = usb_add_hcd(hcd, irq, IRQF_SHARED);
        if (err) {
@@ -210,13 +290,19 @@ static int exynos_ohci_resume(struct device *dev)
 {
        struct usb_hcd *hcd                     = dev_get_drvdata(dev);
        struct exynos_ohci_hcd *exynos_ohci     = to_exynos_ohci(hcd);
+       int ret;
 
        clk_prepare_enable(exynos_ohci->clk);
 
        if (exynos_ohci->otg)
                exynos_ohci->otg->set_host(exynos_ohci->otg, &hcd->self);
 
-       exynos_ohci_phy_enable(dev);
+       ret = exynos_ohci_phy_enable(dev);
+       if (ret) {
+               dev_err(dev, "Failed to enable USB phy\n");
+               clk_disable_unprepare(exynos_ohci->clk);
+               return ret;
+       }
 
        ohci_resume(hcd, false);