linux/drivers/usb/host/ohci-exynos.c
<<
>>
Prefs
   1/*
   2 * SAMSUNG EXYNOS USB HOST OHCI Controller
   3 *
   4 * Copyright (C) 2011 Samsung Electronics Co.Ltd
   5 * Author: Jingoo Han <jg1.han@samsung.com>
   6 *
   7 * This program is free software; you can redistribute  it and/or modify it
   8 * under  the terms of  the GNU General  Public License as published by the
   9 * Free Software Foundation;  either version 2 of the  License, or (at your
  10 * option) any later version.
  11 *
  12 */
  13
  14#include <linux/clk.h>
  15#include <linux/dma-mapping.h>
  16#include <linux/io.h>
  17#include <linux/kernel.h>
  18#include <linux/module.h>
  19#include <linux/of.h>
  20#include <linux/platform_device.h>
  21#include <linux/phy/phy.h>
  22#include <linux/usb.h>
  23#include <linux/usb/hcd.h>
  24
  25#include "ohci.h"
  26
  27#define DRIVER_DESC "OHCI EXYNOS driver"
  28
  29static const char hcd_name[] = "ohci-exynos";
  30static struct hc_driver __read_mostly exynos_ohci_hc_driver;
  31
  32#define to_exynos_ohci(hcd) (struct exynos_ohci_hcd *)(hcd_to_ohci(hcd)->priv)
  33
  34#define PHY_NUMBER 3
  35
  36struct exynos_ohci_hcd {
  37        struct clk *clk;
  38        struct phy *phy[PHY_NUMBER];
  39};
  40
  41static int exynos_ohci_get_phy(struct device *dev,
  42                                struct exynos_ohci_hcd *exynos_ohci)
  43{
  44        struct device_node *child;
  45        struct phy *phy;
  46        int phy_number;
  47        int ret;
  48
  49        /* Get PHYs for the controller */
  50        for_each_available_child_of_node(dev->of_node, child) {
  51                ret = of_property_read_u32(child, "reg", &phy_number);
  52                if (ret) {
  53                        dev_err(dev, "Failed to parse device tree\n");
  54                        of_node_put(child);
  55                        return ret;
  56                }
  57
  58                if (phy_number >= PHY_NUMBER) {
  59                        dev_err(dev, "Invalid number of PHYs\n");
  60                        of_node_put(child);
  61                        return -EINVAL;
  62                }
  63
  64                phy = devm_of_phy_get(dev, child, NULL);
  65                exynos_ohci->phy[phy_number] = phy;
  66                if (IS_ERR(phy)) {
  67                        ret = PTR_ERR(phy);
  68                        if (ret == -EPROBE_DEFER) {
  69                                return ret;
  70                        } else if (ret != -ENOSYS && ret != -ENODEV) {
  71                                dev_err(dev,
  72                                        "Error retrieving usb2 phy: %d\n", ret);
  73                                return ret;
  74                        }
  75                }
  76        }
  77
  78        return 0;
  79}
  80
  81static int exynos_ohci_phy_enable(struct device *dev)
  82{
  83        struct usb_hcd *hcd = dev_get_drvdata(dev);
  84        struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
  85        int i;
  86        int ret = 0;
  87
  88        for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
  89                if (!IS_ERR(exynos_ohci->phy[i]))
  90                        ret = phy_power_on(exynos_ohci->phy[i]);
  91        if (ret)
  92                for (i--; i >= 0; i--)
  93                        if (!IS_ERR(exynos_ohci->phy[i]))
  94                                phy_power_off(exynos_ohci->phy[i]);
  95
  96        return ret;
  97}
  98
  99static void exynos_ohci_phy_disable(struct device *dev)
 100{
 101        struct usb_hcd *hcd = dev_get_drvdata(dev);
 102        struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
 103        int i;
 104
 105        for (i = 0; i < PHY_NUMBER; i++)
 106                if (!IS_ERR(exynos_ohci->phy[i]))
 107                        phy_power_off(exynos_ohci->phy[i]);
 108}
 109
 110static int exynos_ohci_probe(struct platform_device *pdev)
 111{
 112        struct exynos_ohci_hcd *exynos_ohci;
 113        struct usb_hcd *hcd;
 114        struct resource *res;
 115        int irq;
 116        int err;
 117
 118        /*
 119         * Right now device-tree probed devices don't get dma_mask set.
 120         * Since shared usb code relies on it, set it here for now.
 121         * Once we move to full device tree support this will vanish off.
 122         */
 123        err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 124        if (err)
 125                return err;
 126
 127        hcd = usb_create_hcd(&exynos_ohci_hc_driver,
 128                                &pdev->dev, dev_name(&pdev->dev));
 129        if (!hcd) {
 130                dev_err(&pdev->dev, "Unable to create HCD\n");
 131                return -ENOMEM;
 132        }
 133
 134        exynos_ohci = to_exynos_ohci(hcd);
 135
 136        if (of_device_is_compatible(pdev->dev.of_node,
 137                                        "samsung,exynos5440-ohci"))
 138                goto skip_phy;
 139
 140        err = exynos_ohci_get_phy(&pdev->dev, exynos_ohci);
 141        if (err)
 142                goto fail_clk;
 143
 144skip_phy:
 145        exynos_ohci->clk = devm_clk_get(&pdev->dev, "usbhost");
 146
 147        if (IS_ERR(exynos_ohci->clk)) {
 148                dev_err(&pdev->dev, "Failed to get usbhost clock\n");
 149                err = PTR_ERR(exynos_ohci->clk);
 150                goto fail_clk;
 151        }
 152
 153        err = clk_prepare_enable(exynos_ohci->clk);
 154        if (err)
 155                goto fail_clk;
 156
 157        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 158        hcd->regs = devm_ioremap_resource(&pdev->dev, res);
 159        if (IS_ERR(hcd->regs)) {
 160                err = PTR_ERR(hcd->regs);
 161                goto fail_io;
 162        }
 163        hcd->rsrc_start = res->start;
 164        hcd->rsrc_len = resource_size(res);
 165
 166        irq = platform_get_irq(pdev, 0);
 167        if (!irq) {
 168                dev_err(&pdev->dev, "Failed to get IRQ\n");
 169                err = -ENODEV;
 170                goto fail_io;
 171        }
 172
 173        platform_set_drvdata(pdev, hcd);
 174
 175        err = exynos_ohci_phy_enable(&pdev->dev);
 176        if (err) {
 177                dev_err(&pdev->dev, "Failed to enable USB phy\n");
 178                goto fail_io;
 179        }
 180
 181        err = usb_add_hcd(hcd, irq, IRQF_SHARED);
 182        if (err) {
 183                dev_err(&pdev->dev, "Failed to add USB HCD\n");
 184                goto fail_add_hcd;
 185        }
 186        device_wakeup_enable(hcd->self.controller);
 187        return 0;
 188
 189fail_add_hcd:
 190        exynos_ohci_phy_disable(&pdev->dev);
 191fail_io:
 192        clk_disable_unprepare(exynos_ohci->clk);
 193fail_clk:
 194        usb_put_hcd(hcd);
 195        return err;
 196}
 197
 198static int exynos_ohci_remove(struct platform_device *pdev)
 199{
 200        struct usb_hcd *hcd = platform_get_drvdata(pdev);
 201        struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
 202
 203        usb_remove_hcd(hcd);
 204
 205        exynos_ohci_phy_disable(&pdev->dev);
 206
 207        clk_disable_unprepare(exynos_ohci->clk);
 208
 209        usb_put_hcd(hcd);
 210
 211        return 0;
 212}
 213
 214static void exynos_ohci_shutdown(struct platform_device *pdev)
 215{
 216        struct usb_hcd *hcd = platform_get_drvdata(pdev);
 217
 218        if (hcd->driver->shutdown)
 219                hcd->driver->shutdown(hcd);
 220}
 221
 222#ifdef CONFIG_PM
 223static int exynos_ohci_suspend(struct device *dev)
 224{
 225        struct usb_hcd *hcd = dev_get_drvdata(dev);
 226        struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
 227        bool do_wakeup = device_may_wakeup(dev);
 228        int rc = ohci_suspend(hcd, do_wakeup);
 229
 230        if (rc)
 231                return rc;
 232
 233        exynos_ohci_phy_disable(dev);
 234
 235        clk_disable_unprepare(exynos_ohci->clk);
 236
 237        return 0;
 238}
 239
 240static int exynos_ohci_resume(struct device *dev)
 241{
 242        struct usb_hcd *hcd                     = dev_get_drvdata(dev);
 243        struct exynos_ohci_hcd *exynos_ohci     = to_exynos_ohci(hcd);
 244        int ret;
 245
 246        clk_prepare_enable(exynos_ohci->clk);
 247
 248        ret = exynos_ohci_phy_enable(dev);
 249        if (ret) {
 250                dev_err(dev, "Failed to enable USB phy\n");
 251                clk_disable_unprepare(exynos_ohci->clk);
 252                return ret;
 253        }
 254
 255        ohci_resume(hcd, false);
 256
 257        return 0;
 258}
 259#else
 260#define exynos_ohci_suspend     NULL
 261#define exynos_ohci_resume      NULL
 262#endif
 263
 264static const struct ohci_driver_overrides exynos_overrides __initconst = {
 265        .extra_priv_size =      sizeof(struct exynos_ohci_hcd),
 266};
 267
 268static const struct dev_pm_ops exynos_ohci_pm_ops = {
 269        .suspend        = exynos_ohci_suspend,
 270        .resume         = exynos_ohci_resume,
 271};
 272
 273#ifdef CONFIG_OF
 274static const struct of_device_id exynos_ohci_match[] = {
 275        { .compatible = "samsung,exynos4210-ohci" },
 276        { .compatible = "samsung,exynos5440-ohci" },
 277        {},
 278};
 279MODULE_DEVICE_TABLE(of, exynos_ohci_match);
 280#endif
 281
 282static struct platform_driver exynos_ohci_driver = {
 283        .probe          = exynos_ohci_probe,
 284        .remove         = exynos_ohci_remove,
 285        .shutdown       = exynos_ohci_shutdown,
 286        .driver = {
 287                .name   = "exynos-ohci",
 288                .pm     = &exynos_ohci_pm_ops,
 289                .of_match_table = of_match_ptr(exynos_ohci_match),
 290        }
 291};
 292static int __init ohci_exynos_init(void)
 293{
 294        if (usb_disabled())
 295                return -ENODEV;
 296
 297        pr_info("%s: " DRIVER_DESC "\n", hcd_name);
 298        ohci_init_driver(&exynos_ohci_hc_driver, &exynos_overrides);
 299        return platform_driver_register(&exynos_ohci_driver);
 300}
 301module_init(ohci_exynos_init);
 302
 303static void __exit ohci_exynos_cleanup(void)
 304{
 305        platform_driver_unregister(&exynos_ohci_driver);
 306}
 307module_exit(ohci_exynos_cleanup);
 308
 309MODULE_ALIAS("platform:exynos-ohci");
 310MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
 311MODULE_LICENSE("GPL v2");
 312