drivers/usb/host/ohci-exynos.c

   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
  24 static struct hc_driver __read_mostly exynos_ohci_hc_driver;
  25
  26 #define to_exynos_ohci(hcd) (struct exynos_ohci_hcd *)(hcd_to_ohci(hcd)->priv)
  27
  28 #define PHY_NUMBER 3
  29
  30 struct exynos_ohci_hcd {
  31         struct clk *clk;
  32         struct device_node *of_node;
  33         struct phy *phy[PHY_NUMBER];
  34         bool legacy_phy;
  35 };
  36
  37 static int exynos_ohci_get_phy(struct device *dev,
  38                                 struct exynos_ohci_hcd *exynos_ohci)
  39 {
  40         struct device_node *child;
  41         struct phy *phy;
  42         int phy_number, num_phys;
  43         int ret;
  44
  45         /* Get PHYs for the controller */
  46         num_phys = of_count_phandle_with_args(dev->of_node, "phys",
  47                                               "#phy-cells");
  48         for (phy_number = 0; phy_number < num_phys; phy_number++) {
  49                 phy = devm_of_phy_get_by_index(dev, dev->of_node, phy_number);
  50                 if (IS_ERR(phy))
  51                         return PTR_ERR(phy);
  52                 exynos_ohci->phy[phy_number] = phy;
  53         }
  54         if (num_phys > 0)
  55                 return 0;
  56
  57         /* Get PHYs using legacy bindings */
  58         for_each_available_child_of_node(dev->of_node, child) {
  59                 ret = of_property_read_u32(child, "reg", &phy_number);
  60                 if (ret) {
  61                         dev_err(dev, "Failed to parse device tree\n");
  62                         of_node_put(child);
  63                         return ret;
  64                 }
  65
  66                 if (phy_number >= PHY_NUMBER) {
  67                         dev_err(dev, "Invalid number of PHYs\n");
  68                         of_node_put(child);
  69                         return -EINVAL;
  70                 }
  71
  72                 phy = devm_of_phy_optional_get(dev, child, NULL);
  73                 exynos_ohci->phy[phy_number] = phy;
  74                 if (IS_ERR(phy)) {
  75                         of_node_put(child);
  76                         return PTR_ERR(phy);
  77                 }
  78         }
  79
  80         exynos_ohci->legacy_phy = true;
  81         return 0;
  82 }
  83
  84 static int exynos_ohci_phy_enable(struct device *dev)
  85 {
  86         struct usb_hcd *hcd = dev_get_drvdata(dev);
  87         struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
  88         int i;
  89         int ret = 0;
  90
  91         for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
  92                 ret = phy_power_on(exynos_ohci->phy[i]);
  93         if (ret)
  94                 for (i--; i >= 0; i--)
  95                         phy_power_off(exynos_ohci->phy[i]);
  96
  97         return ret;
  98 }
  99
 100 static void exynos_ohci_phy_disable(struct device *dev)
 101 {
 102         struct usb_hcd *hcd = dev_get_drvdata(dev);
 103         struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
 104         int i;
 105
 106         for (i = 0; i < PHY_NUMBER; i++)
 107                 phy_power_off(exynos_ohci->phy[i]);
 108 }
 109
 110 static 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         err = exynos_ohci_get_phy(&pdev->dev, exynos_ohci);
 137         if (err)
 138                 goto fail_clk;
 139
 140         exynos_ohci->clk = devm_clk_get(&pdev->dev, "usbhost");
 141
 142         if (IS_ERR(exynos_ohci->clk)) {
 143                 dev_err(&pdev->dev, "Failed to get usbhost clock\n");
 144                 err = PTR_ERR(exynos_ohci->clk);
 145                 goto fail_clk;
 146         }
 147
 148         err = clk_prepare_enable(exynos_ohci->clk);
 149         if (err)
 150                 goto fail_clk;
 151
 152         hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 153         if (IS_ERR(hcd->regs)) {
 154                 err = PTR_ERR(hcd->regs);
 155                 goto fail_io;
 156         }
 157         hcd->rsrc_start = res->start;
 158         hcd->rsrc_len = resource_size(res);
 159
 160         irq = platform_get_irq(pdev, 0);
 161         if (irq < 0) {
 162                 err = irq;
 163                 goto fail_io;
 164         }
 165
 166         platform_set_drvdata(pdev, hcd);
 167
 168         err = exynos_ohci_phy_enable(&pdev->dev);
 169         if (err) {
 170                 dev_err(&pdev->dev, "Failed to enable USB phy\n");
 171                 goto fail_io;
 172         }
 173
 174         /*
 175          * Workaround: reset of_node pointer to avoid conflict between legacy
 176          * Exynos OHCI port subnodes and generic USB device bindings
 177          */
 178         exynos_ohci->of_node = pdev->dev.of_node;
 179         if (exynos_ohci->legacy_phy)
 180                 pdev->dev.of_node = NULL;
 181
 182         err = usb_add_hcd(hcd, irq, IRQF_SHARED);
 183         if (err) {
 184                 dev_err(&pdev->dev, "Failed to add USB HCD\n");
 185                 goto fail_add_hcd;
 186         }
 187         device_wakeup_enable(hcd->self.controller);
 188         return 0;
 189
 190 fail_add_hcd:
 191         exynos_ohci_phy_disable(&pdev->dev);
 192         pdev->dev.of_node = exynos_ohci->of_node;
 193 fail_io:
 194         clk_disable_unprepare(exynos_ohci->clk);
 195 fail_clk:
 196         usb_put_hcd(hcd);
 197         return err;
 198 }
 199
 200 static void exynos_ohci_remove(struct platform_device *pdev)
 201 {
 202         struct usb_hcd *hcd = platform_get_drvdata(pdev);
 203         struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
 204
 205         pdev->dev.of_node = exynos_ohci->of_node;
 206
 207         usb_remove_hcd(hcd);
 208
 209         exynos_ohci_phy_disable(&pdev->dev);
 210
 211         clk_disable_unprepare(exynos_ohci->clk);
 212
 213         usb_put_hcd(hcd);
 214 }
 215
 216 static void exynos_ohci_shutdown(struct platform_device *pdev)
 217 {
 218         struct usb_hcd *hcd = platform_get_drvdata(pdev);
 219
 220         if (hcd->driver->shutdown)
 221                 hcd->driver->shutdown(hcd);
 222 }
 223
 224 #ifdef CONFIG_PM
 225 static int exynos_ohci_suspend(struct device *dev)
 226 {
 227         struct usb_hcd *hcd = dev_get_drvdata(dev);
 228         struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
 229         bool do_wakeup = device_may_wakeup(dev);
 230         int rc = ohci_suspend(hcd, do_wakeup);
 231
 232         if (rc)
 233                 return rc;
 234
 235         exynos_ohci_phy_disable(dev);
 236
 237         clk_disable_unprepare(exynos_ohci->clk);
 238
 239         return 0;
 240 }
 241
 242 static int exynos_ohci_resume(struct device *dev)
 243 {
 244         struct usb_hcd *hcd                     = dev_get_drvdata(dev);
 245         struct exynos_ohci_hcd *exynos_ohci     = to_exynos_ohci(hcd);
 246         int ret;
 247
 248         clk_prepare_enable(exynos_ohci->clk);
 249
 250         ret = exynos_ohci_phy_enable(dev);
 251         if (ret) {
 252                 dev_err(dev, "Failed to enable USB phy\n");
 253                 clk_disable_unprepare(exynos_ohci->clk);
 254                 return ret;
 255         }
 256
 257         ohci_resume(hcd, false);
 258
 259         return 0;
 260 }
 261 #else
 262 #define exynos_ohci_suspend     NULL
 263 #define exynos_ohci_resume      NULL
 264 #endif
 265
 266 static const struct ohci_driver_overrides exynos_overrides __initconst = {
 267         .extra_priv_size =      sizeof(struct exynos_ohci_hcd),
 268 };
 269
 270 static const struct dev_pm_ops exynos_ohci_pm_ops = {
 271         .suspend        = exynos_ohci_suspend,
 272         .resume         = exynos_ohci_resume,
 273 };
 274
 275 #ifdef CONFIG_OF
 276 static const struct of_device_id exynos_ohci_match[] = {
 277         { .compatible = "samsung,exynos4210-ohci" },
 278         {},
 279 };
 280 MODULE_DEVICE_TABLE(of, exynos_ohci_match);
 281 #endif
 282
 283 static struct platform_driver exynos_ohci_driver = {
 284         .probe          = exynos_ohci_probe,
 285         .remove_new     = exynos_ohci_remove,
 286         .shutdown       = exynos_ohci_shutdown,
 287         .driver = {
 288                 .name   = "exynos-ohci",
 289                 .pm     = &exynos_ohci_pm_ops,
 290                 .of_match_table = of_match_ptr(exynos_ohci_match),
 291         }
 292 };
 293 static int __init ohci_exynos_init(void)
 294 {
 295         if (usb_disabled())
 296                 return -ENODEV;
 297
 298         ohci_init_driver(&exynos_ohci_hc_driver, &exynos_overrides);
 299         return platform_driver_register(&exynos_ohci_driver);
 300 }
 301 module_init(ohci_exynos_init);
 302
 303 static void __exit ohci_exynos_cleanup(void)
 304 {
 305         platform_driver_unregister(&exynos_ohci_driver);
 306 }
 307 module_exit(ohci_exynos_cleanup);
 308
 309 MODULE_ALIAS("platform:exynos-ohci");
 310 MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
 311 MODULE_LICENSE("GPL v2");