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 const char hcd_name[] = "ohci-exynos";
  25 static 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
  31 struct 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
  38 static 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
  93 static 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
 111 static 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
 122 static 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
 203 fail_add_hcd:
 204         exynos_ohci_phy_disable(&pdev->dev);
 205         pdev->dev.of_node = exynos_ohci->of_node;
 206 fail_io:
 207         clk_disable_unprepare(exynos_ohci->clk);
 208 fail_clk:
 209         usb_put_hcd(hcd);
 210         return err;
 211 }
 212
 213 static 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
 231 static 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
 240 static 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
 257 static 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
 281 static const struct ohci_driver_overrides exynos_overrides __initconst = {
 282         .extra_priv_size =      sizeof(struct exynos_ohci_hcd),
 283 };
 284
 285 static 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
 291 static const struct of_device_id exynos_ohci_match[] = {
 292         { .compatible = "samsung,exynos4210-ohci" },
 293         {},
 294 };
 295 MODULE_DEVICE_TABLE(of, exynos_ohci_match);
 296 #endif
 297
 298 static 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 };
 308 static 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 }
 317 module_init(ohci_exynos_init);
 318
 319 static void __exit ohci_exynos_cleanup(void)
 320 {
 321         platform_driver_unregister(&exynos_ohci_driver);
 322 }
 323 module_exit(ohci_exynos_cleanup);
 324
 325 MODULE_ALIAS("platform:exynos-ohci");
 326 MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
 327 MODULE_LICENSE("GPL v2");