ohci-platform: Add support for devicetree instantiation

Add support for ohci-platform instantiation from devicetree, including
optionally getting clks and a phy from devicetree, and enabling / disabling
those on power_on / off.

This should allow using ohci-platform from devicetree in various cases.
Specifically after this commit it can be used for the ohci controller found
on Allwinner sunxi SoCs.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/devicetree/bindings/usb/usb-ohci.txt b/Documentation/devicetree/bindings/usb/usb-ohci.txt
new file mode 100644 (file)
index 0000000..6ba38d9
--- /dev/null
+++ b/Documentation/devicetree/bindings/usb/usb-ohci.txt
@@ -0,0 +1,22 @@
+USB OHCI controllers
+
+Required properties:
+- compatible : "usb-ohci"
+- reg : ohci controller register range (address and length)
+- interrupts : ohci controller interrupt
+
+Optional properties:
+- clocks : a list of phandle + clock specifier pairs
+- phys : phandle + phy specifier pair
+- phy-names : "usb"
+
+Example:
+
+       ohci0: usb@01c14400 {
+               compatible = "allwinner,sun4i-a10-ohci", "usb-ohci";
+               reg = <0x01c14400 0x100>;
+               interrupts = <64>;
+               clocks = <&usb_clk 6>, <&ahb_gates 2>;
+               phys = <&usbphy 1>;
+               phy-names = "usb";
+       };

diff --git a/drivers/usb/host/ohci-platform.c b/drivers/usb/host/ohci-platform.c
index 68f674c..49304dd 100644 (file)
--- a/drivers/usb/host/ohci-platform.c
+++ b/drivers/usb/host/ohci-platform.c
@@ -3,6 +3,7 @@
  *
  * Copyright 2007 Michael Buesch <m@bues.ch>
  * Copyright 2011-2012 Hauke Mehrtens <hauke@hauke-m.de>
+ * Copyright 2014 Hans de Goede <hdegoede@redhat.com>
  *
  * Derived from the OCHI-SSB driver
  * Derived from the OHCI-PCI driver
@@ -14,11 +15,14 @@
  * Licensed under the GNU/GPL. See COPYING for details.
  */
 
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
 #include <linux/hrtimer.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/err.h>
+#include <linux/phy/phy.h>
 #include <linux/platform_device.h>
 #include <linux/usb/ohci_pdriver.h>
 #include <linux/usb.h>
@@ -27,6 +31,13 @@
 #include "ohci.h"
 
 #define DRIVER_DESC "OHCI generic platform driver"
+#define OHCI_MAX_CLKS 3
+#define hcd_to_ohci_priv(h) ((struct ohci_platform_priv *)hcd_to_ohci(h)->priv)
+
+struct ohci_platform_priv {
+       struct clk *clks[OHCI_MAX_CLKS];
+       struct phy *phy;
+};
 
 static const char hcd_name[] = "ohci-platform";
 
@@ -48,11 +59,67 @@ static int ohci_platform_reset(struct usb_hcd *hcd)
        return ohci_setup(hcd);
 }
 
+static int ohci_platform_power_on(struct platform_device *dev)
+{
+       struct usb_hcd *hcd = platform_get_drvdata(dev);
+       struct ohci_platform_priv *priv = hcd_to_ohci_priv(hcd);
+       int clk, ret;
+
+       for (clk = 0; clk < OHCI_MAX_CLKS && priv->clks[clk]; clk++) {
+               ret = clk_prepare_enable(priv->clks[clk]);
+               if (ret)
+                       goto err_disable_clks;
+       }
+
+       if (priv->phy) {
+               ret = phy_init(priv->phy);
+               if (ret)
+                       goto err_disable_clks;
+
+               ret = phy_power_on(priv->phy);
+               if (ret)
+                       goto err_exit_phy;
+       }
+
+       return 0;
+
+err_exit_phy:
+       phy_exit(priv->phy);
+err_disable_clks:
+       while (--clk >= 0)
+               clk_disable_unprepare(priv->clks[clk]);
+
+       return ret;
+}
+
+static void ohci_platform_power_off(struct platform_device *dev)
+{
+       struct usb_hcd *hcd = platform_get_drvdata(dev);
+       struct ohci_platform_priv *priv = hcd_to_ohci_priv(hcd);
+       int clk;
+
+       if (priv->phy) {
+               phy_power_off(priv->phy);
+               phy_exit(priv->phy);
+       }
+
+       for (clk = OHCI_MAX_CLKS - 1; clk >= 0; clk--)
+               if (priv->clks[clk])
+                       clk_disable_unprepare(priv->clks[clk]);
+}
+
 static struct hc_driver __read_mostly ohci_platform_hc_driver;
 
 static const struct ohci_driver_overrides platform_overrides __initconst = {
-       .product_desc = "Generic Platform OHCI controller",
-       .reset =        ohci_platform_reset,
+       .product_desc =         "Generic Platform OHCI controller",
+       .reset =                ohci_platform_reset,
+       .extra_priv_size =      sizeof(struct ohci_platform_priv),
+};
+
+static struct usb_ohci_pdata ohci_platform_defaults = {
+       .power_on =             ohci_platform_power_on,
+       .power_suspend =        ohci_platform_power_off,
+       .power_off =            ohci_platform_power_off,
 };
 
 static int ohci_platform_probe(struct platform_device *dev)
@@ -60,17 +127,23 @@ static int ohci_platform_probe(struct platform_device *dev)
        struct usb_hcd *hcd;
        struct resource *res_mem;
        struct usb_ohci_pdata *pdata = dev_get_platdata(&dev->dev);
-       int irq;
-       int err = -ENOMEM;
-
-       if (!pdata) {
-               WARN_ON(1);
-               return -ENODEV;
-       }
+       struct ohci_platform_priv *priv;
+       int err, irq, clk = 0;
 
        if (usb_disabled())
                return -ENODEV;
 
+       /*
+        * Use reasonable defaults so platforms don't have to provide these
+        * with DT probing on ARM.
+        */
+       if (!pdata)
+               pdata = &ohci_platform_defaults;
+
+       err = dma_coerce_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32));
+       if (err)
+               return err;
+
        irq = platform_get_irq(dev, 0);
        if (irq < 0) {
                dev_err(&dev->dev, "no irq provided");
@@ -83,17 +156,40 @@ static int ohci_platform_probe(struct platform_device *dev)
                return -ENXIO;
        }
 
+       hcd = usb_create_hcd(&ohci_platform_hc_driver, &dev->dev,
+                       dev_name(&dev->dev));
+       if (!hcd)
+               return -ENOMEM;
+
+       platform_set_drvdata(dev, hcd);
+       dev->dev.platform_data = pdata;
+       priv = hcd_to_ohci_priv(hcd);
+
+       if (pdata == &ohci_platform_defaults && dev->dev.of_node) {
+               priv->phy = devm_phy_get(&dev->dev, "usb");
+               if (IS_ERR(priv->phy)) {
+                       err = PTR_ERR(priv->phy);
+                       if (err == -EPROBE_DEFER)
+                               goto err_put_hcd;
+                       priv->phy = NULL;
+               }
+
+               for (clk = 0; clk < OHCI_MAX_CLKS; clk++) {
+                       priv->clks[clk] = of_clk_get(dev->dev.of_node, clk);
+                       if (IS_ERR(priv->clks[clk])) {
+                               err = PTR_ERR(priv->clks[clk]);
+                               if (err == -EPROBE_DEFER)
+                                       goto err_put_clks;
+                               priv->clks[clk] = NULL;
+                               break;
+                       }
+               }
+       }
+
        if (pdata->power_on) {
                err = pdata->power_on(dev);
                if (err < 0)
-                       return err;
-       }
-
-       hcd = usb_create_hcd(&ohci_platform_hc_driver, &dev->dev,
-                       dev_name(&dev->dev));
-       if (!hcd) {
-               err = -ENOMEM;
-               goto err_power;
+                       goto err_put_clks;
        }
 
        hcd->rsrc_start = res_mem->start;
@@ -102,11 +198,11 @@ static int ohci_platform_probe(struct platform_device *dev)
        hcd->regs = devm_ioremap_resource(&dev->dev, res_mem);
        if (IS_ERR(hcd->regs)) {
                err = PTR_ERR(hcd->regs);
-               goto err_put_hcd;
+               goto err_power;
        }
        err = usb_add_hcd(hcd, irq, IRQF_SHARED);
        if (err)
-               goto err_put_hcd;
+               goto err_power;
 
        device_wakeup_enable(hcd->self.controller);
 
@@ -114,11 +210,17 @@ static int ohci_platform_probe(struct platform_device *dev)
 
        return err;
 
-err_put_hcd:
-       usb_put_hcd(hcd);
 err_power:
        if (pdata->power_off)
                pdata->power_off(dev);
+err_put_clks:
+       while (--clk >= 0)
+               clk_put(priv->clks[clk]);
+err_put_hcd:
+       if (pdata == &ohci_platform_defaults)
+               dev->dev.platform_data = NULL;
+
+       usb_put_hcd(hcd);
 
        return err;
 }
@@ -127,13 +229,22 @@ static int ohci_platform_remove(struct platform_device *dev)
 {
        struct usb_hcd *hcd = platform_get_drvdata(dev);
        struct usb_ohci_pdata *pdata = dev_get_platdata(&dev->dev);
+       struct ohci_platform_priv *priv = hcd_to_ohci_priv(hcd);
+       int clk;
 
        usb_remove_hcd(hcd);
-       usb_put_hcd(hcd);
 
        if (pdata->power_off)
                pdata->power_off(dev);
 
+       for (clk = 0; clk < OHCI_MAX_CLKS && priv->clks[clk]; clk++)
+               clk_put(priv->clks[clk]);
+
+       usb_put_hcd(hcd);
+
+       if (pdata == &ohci_platform_defaults)
+               dev->dev.platform_data = NULL;
+
        return 0;
 }
 
@@ -180,6 +291,12 @@ static int ohci_platform_resume(struct device *dev)
 #define ohci_platform_resume   NULL
 #endif /* CONFIG_PM */
 
+static const struct of_device_id ohci_platform_ids[] = {
+       { .compatible = "usb-ohci", },
+       { }
+};
+MODULE_DEVICE_TABLE(of, ohci_platform_ids);
+
 static const struct platform_device_id ohci_platform_table[] = {
        { "ohci-platform", 0 },
        { }
@@ -200,6 +317,7 @@ static struct platform_driver ohci_platform_driver = {
                .owner  = THIS_MODULE,
                .name   = "ohci-platform",
                .pm     = &ohci_platform_pm_ops,
+               .of_match_table = ohci_platform_ids,
        }
 };