linux/drivers/usb/host/ohci-exynos.c
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   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * SAMSUNG EXYNOS USB HOST OHCI Controller
   4 *
   5 * Copyright (C) 2011 Samsung Electronics Co.Ltd
   6 * Author: Jingoo Han <jg1.han@samsung.com>
   7 */
   8
   9#include <linux/clk.h>
  10#include <linux/dma-mapping.h>
  11#include <linux/io.h>
  12#include <linux/kernel.h>
  13#include <linux/module.h>
  14#include <linux/of.h>
  15#include <linux/platform_device.h>
  16#include <linux/phy/phy.h>
  17#include <linux/usb.h>
  18#include <linux/usb/hcd.h>
  19
  20#include "ohci.h"
  21
  22#define DRIVER_DESC "OHCI Exynos driver"
  23
  24static const char hcd_name[] = "ohci-exynos";
  25static struct hc_driver __read_mostly exynos_ohci_hc_driver;
  26
  27#define to_exynos_ohci(hcd) (struct exynos_ohci_hcd *)(hcd_to_ohci(hcd)->priv)
  28
  29#define PHY_NUMBER 3
  30
  31struct exynos_ohci_hcd {
  32        struct clk *clk;
  33        struct device_node *of_node;
  34        struct phy *phy[PHY_NUMBER];
  35        bool legacy_phy;
  36};
  37
  38static int exynos_ohci_get_phy(struct device *dev,
  39                                struct exynos_ohci_hcd *exynos_ohci)
  40{
  41        struct device_node *child;
  42        struct phy *phy;
  43        int phy_number, num_phys;
  44        int ret;
  45
  46        /* Get PHYs for the controller */
  47        num_phys = of_count_phandle_with_args(dev->of_node, "phys",
  48                                              "#phy-cells");
  49        for (phy_number = 0; phy_number < num_phys; phy_number++) {
  50                phy = devm_of_phy_get_by_index(dev, dev->of_node, phy_number);
  51                if (IS_ERR(phy))
  52                        return PTR_ERR(phy);
  53                exynos_ohci->phy[phy_number] = phy;
  54        }
  55        if (num_phys > 0)
  56                return 0;
  57
  58        /* Get PHYs using legacy bindings */
  59        for_each_available_child_of_node(dev->of_node, child) {
  60                ret = of_property_read_u32(child, "reg", &phy_number);
  61                if (ret) {
  62                        dev_err(dev, "Failed to parse device tree\n");
  63                        of_node_put(child);
  64                        return ret;
  65                }
  66
  67                if (phy_number >= PHY_NUMBER) {
  68                        dev_err(dev, "Invalid number of PHYs\n");
  69                        of_node_put(child);
  70                        return -EINVAL;
  71                }
  72
  73                phy = devm_of_phy_get(dev, child, NULL);
  74                exynos_ohci->phy[phy_number] = phy;
  75                if (IS_ERR(phy)) {
  76                        ret = PTR_ERR(phy);
  77                        if (ret == -EPROBE_DEFER) {
  78                                of_node_put(child);
  79                                return ret;
  80                        } else if (ret != -ENOSYS && ret != -ENODEV) {
  81                                dev_err(dev,
  82                                        "Error retrieving usb2 phy: %d\n", ret);
  83                                of_node_put(child);
  84                                return ret;
  85                        }
  86                }
  87        }
  88
  89        exynos_ohci->legacy_phy = true;
  90        return 0;
  91}
  92
  93static int exynos_ohci_phy_enable(struct device *dev)
  94{
  95        struct usb_hcd *hcd = dev_get_drvdata(dev);
  96        struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
  97        int i;
  98        int ret = 0;
  99
 100        for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
 101                if (!IS_ERR(exynos_ohci->phy[i]))
 102                        ret = phy_power_on(exynos_ohci->phy[i]);
 103        if (ret)
 104                for (i--; i >= 0; i--)
 105                        if (!IS_ERR(exynos_ohci->phy[i]))
 106                                phy_power_off(exynos_ohci->phy[i]);
 107
 108        return ret;
 109}
 110
 111static void exynos_ohci_phy_disable(struct device *dev)
 112{
 113        struct usb_hcd *hcd = dev_get_drvdata(dev);
 114        struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
 115        int i;
 116
 117        for (i = 0; i < PHY_NUMBER; i++)
 118                if (!IS_ERR(exynos_ohci->phy[i]))
 119                        phy_power_off(exynos_ohci->phy[i]);
 120}
 121
 122static int exynos_ohci_probe(struct platform_device *pdev)
 123{
 124        struct exynos_ohci_hcd *exynos_ohci;
 125        struct usb_hcd *hcd;
 126        struct resource *res;
 127        int irq;
 128        int err;
 129
 130        /*
 131         * Right now device-tree probed devices don't get dma_mask set.
 132         * Since shared usb code relies on it, set it here for now.
 133         * Once we move to full device tree support this will vanish off.
 134         */
 135        err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 136        if (err)
 137                return err;
 138
 139        hcd = usb_create_hcd(&exynos_ohci_hc_driver,
 140                                &pdev->dev, dev_name(&pdev->dev));
 141        if (!hcd) {
 142                dev_err(&pdev->dev, "Unable to create HCD\n");
 143                return -ENOMEM;
 144        }
 145
 146        exynos_ohci = to_exynos_ohci(hcd);
 147
 148        err = exynos_ohci_get_phy(&pdev->dev, exynos_ohci);
 149        if (err)
 150                goto fail_clk;
 151
 152        exynos_ohci->clk = devm_clk_get(&pdev->dev, "usbhost");
 153
 154        if (IS_ERR(exynos_ohci->clk)) {
 155                dev_err(&pdev->dev, "Failed to get usbhost clock\n");
 156                err = PTR_ERR(exynos_ohci->clk);
 157                goto fail_clk;
 158        }
 159
 160        err = clk_prepare_enable(exynos_ohci->clk);
 161        if (err)
 162                goto fail_clk;
 163
 164        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 165        hcd->regs = devm_ioremap_resource(&pdev->dev, res);
 166        if (IS_ERR(hcd->regs)) {
 167                err = PTR_ERR(hcd->regs);
 168                goto fail_io;
 169        }
 170        hcd->rsrc_start = res->start;
 171        hcd->rsrc_len = resource_size(res);
 172
 173        irq = platform_get_irq(pdev, 0);
 174        if (irq < 0) {
 175                err = irq;
 176                goto fail_io;
 177        }
 178
 179        platform_set_drvdata(pdev, hcd);
 180
 181        err = exynos_ohci_phy_enable(&pdev->dev);
 182        if (err) {
 183                dev_err(&pdev->dev, "Failed to enable USB phy\n");
 184                goto fail_io;
 185        }
 186
 187        /*
 188         * Workaround: reset of_node pointer to avoid conflict between legacy
 189         * Exynos OHCI port subnodes and generic USB device bindings
 190         */
 191        exynos_ohci->of_node = pdev->dev.of_node;
 192        if (exynos_ohci->legacy_phy)
 193                pdev->dev.of_node = NULL;
 194
 195        err = usb_add_hcd(hcd, irq, IRQF_SHARED);
 196        if (err) {
 197                dev_err(&pdev->dev, "Failed to add USB HCD\n");
 198                goto fail_add_hcd;
 199        }
 200        device_wakeup_enable(hcd->self.controller);
 201        return 0;
 202
 203fail_add_hcd:
 204        exynos_ohci_phy_disable(&pdev->dev);
 205        pdev->dev.of_node = exynos_ohci->of_node;
 206fail_io:
 207        clk_disable_unprepare(exynos_ohci->clk);
 208fail_clk:
 209        usb_put_hcd(hcd);
 210        return err;
 211}
 212
 213static int exynos_ohci_remove(struct platform_device *pdev)
 214{
 215        struct usb_hcd *hcd = platform_get_drvdata(pdev);
 216        struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
 217
 218        pdev->dev.of_node = exynos_ohci->of_node;
 219
 220        usb_remove_hcd(hcd);
 221
 222        exynos_ohci_phy_disable(&pdev->dev);
 223
 224        clk_disable_unprepare(exynos_ohci->clk);
 225
 226        usb_put_hcd(hcd);
 227
 228        return 0;
 229}
 230
 231static void exynos_ohci_shutdown(struct platform_device *pdev)
 232{
 233        struct usb_hcd *hcd = platform_get_drvdata(pdev);
 234
 235        if (hcd->driver->shutdown)
 236                hcd->driver->shutdown(hcd);
 237}
 238
 239#ifdef CONFIG_PM
 240static int exynos_ohci_suspend(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        bool do_wakeup = device_may_wakeup(dev);
 245        int rc = ohci_suspend(hcd, do_wakeup);
 246
 247        if (rc)
 248                return rc;
 249
 250        exynos_ohci_phy_disable(dev);
 251
 252        clk_disable_unprepare(exynos_ohci->clk);
 253
 254        return 0;
 255}
 256
 257static int exynos_ohci_resume(struct device *dev)
 258{
 259        struct usb_hcd *hcd                     = dev_get_drvdata(dev);
 260        struct exynos_ohci_hcd *exynos_ohci     = to_exynos_ohci(hcd);
 261        int ret;
 262
 263        clk_prepare_enable(exynos_ohci->clk);
 264
 265        ret = exynos_ohci_phy_enable(dev);
 266        if (ret) {
 267                dev_err(dev, "Failed to enable USB phy\n");
 268                clk_disable_unprepare(exynos_ohci->clk);
 269                return ret;
 270        }
 271
 272        ohci_resume(hcd, false);
 273
 274        return 0;
 275}
 276#else
 277#define exynos_ohci_suspend     NULL
 278#define exynos_ohci_resume      NULL
 279#endif
 280
 281static const struct ohci_driver_overrides exynos_overrides __initconst = {
 282        .extra_priv_size =      sizeof(struct exynos_ohci_hcd),
 283};
 284
 285static const struct dev_pm_ops exynos_ohci_pm_ops = {
 286        .suspend        = exynos_ohci_suspend,
 287        .resume         = exynos_ohci_resume,
 288};
 289
 290#ifdef CONFIG_OF
 291static const struct of_device_id exynos_ohci_match[] = {
 292        { .compatible = "samsung,exynos4210-ohci" },
 293        {},
 294};
 295MODULE_DEVICE_TABLE(of, exynos_ohci_match);
 296#endif
 297
 298static struct platform_driver exynos_ohci_driver = {
 299        .probe          = exynos_ohci_probe,
 300        .remove         = exynos_ohci_remove,
 301        .shutdown       = exynos_ohci_shutdown,
 302        .driver = {
 303                .name   = "exynos-ohci",
 304                .pm     = &exynos_ohci_pm_ops,
 305                .of_match_table = of_match_ptr(exynos_ohci_match),
 306        }
 307};
 308static int __init ohci_exynos_init(void)
 309{
 310        if (usb_disabled())
 311                return -ENODEV;
 312
 313        pr_info("%s: " DRIVER_DESC "\n", hcd_name);
 314        ohci_init_driver(&exynos_ohci_hc_driver, &exynos_overrides);
 315        return platform_driver_register(&exynos_ohci_driver);
 316}
 317module_init(ohci_exynos_init);
 318
 319static void __exit ohci_exynos_cleanup(void)
 320{
 321        platform_driver_unregister(&exynos_ohci_driver);
 322}
 323module_exit(ohci_exynos_cleanup);
 324
 325MODULE_ALIAS("platform:exynos-ohci");
 326MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
 327MODULE_LICENSE("GPL v2");
 328