drivers/usb/host/ehci-exynos.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * SAMSUNG EXYNOS USB HOST EHCI Controller
   4  *
   5  * Copyright (C) 2011 Samsung Electronics Co.Ltd
   6  * Author: Jingoo Han <jg1.han@samsung.com>
   7  * Author: Joonyoung Shim <jy0922.shim@samsung.com>
   8  */
   9
  10 #include <linux/clk.h>
  11 #include <linux/dma-mapping.h>
  12 #include <linux/io.h>
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/of.h>
  16 #include <linux/of_gpio.h>
  17 #include <linux/phy/phy.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/usb.h>
  20 #include <linux/usb/hcd.h>
  21
  22 #include "ehci.h"
  23
  24 #define DRIVER_DESC "EHCI EXYNOS driver"
  25
  26 #define EHCI_INSNREG00(base)                    (base + 0x90)
  27 #define EHCI_INSNREG00_ENA_INCR16               (0x1 << 25)
  28 #define EHCI_INSNREG00_ENA_INCR8                (0x1 << 24)
  29 #define EHCI_INSNREG00_ENA_INCR4                (0x1 << 23)
  30 #define EHCI_INSNREG00_ENA_INCRX_ALIGN          (0x1 << 22)
  31 #define EHCI_INSNREG00_ENABLE_DMA_BURST \
  32         (EHCI_INSNREG00_ENA_INCR16 | EHCI_INSNREG00_ENA_INCR8 | \
  33          EHCI_INSNREG00_ENA_INCR4 | EHCI_INSNREG00_ENA_INCRX_ALIGN)
  34
  35 static const char hcd_name[] = "ehci-exynos";
  36 static struct hc_driver __read_mostly exynos_ehci_hc_driver;
  37
  38 #define PHY_NUMBER 3
  39
  40 struct exynos_ehci_hcd {
  41         struct clk *clk;
  42         struct device_node *of_node;
  43         struct phy *phy[PHY_NUMBER];
  44         bool legacy_phy;
  45 };
  46
  47 #define to_exynos_ehci(hcd) (struct exynos_ehci_hcd *)(hcd_to_ehci(hcd)->priv)
  48
  49 static int exynos_ehci_get_phy(struct device *dev,
  50                                 struct exynos_ehci_hcd *exynos_ehci)
  51 {
  52         struct device_node *child;
  53         struct phy *phy;
  54         int phy_number, num_phys;
  55         int ret;
  56
  57         /* Get PHYs for the controller */
  58         num_phys = of_count_phandle_with_args(dev->of_node, "phys",
  59                                               "#phy-cells");
  60         for (phy_number = 0; phy_number < num_phys; phy_number++) {
  61                 phy = devm_of_phy_get_by_index(dev, dev->of_node, phy_number);
  62                 if (IS_ERR(phy))
  63                         return PTR_ERR(phy);
  64                 exynos_ehci->phy[phy_number] = phy;
  65         }
  66         if (num_phys > 0)
  67                 return 0;
  68
  69         /* Get PHYs using legacy bindings */
  70         for_each_available_child_of_node(dev->of_node, child) {
  71                 ret = of_property_read_u32(child, "reg", &phy_number);
  72                 if (ret) {
  73                         dev_err(dev, "Failed to parse device tree\n");
  74                         of_node_put(child);
  75                         return ret;
  76                 }
  77
  78                 if (phy_number >= PHY_NUMBER) {
  79                         dev_err(dev, "Invalid number of PHYs\n");
  80                         of_node_put(child);
  81                         return -EINVAL;
  82                 }
  83
  84                 phy = devm_of_phy_get(dev, child, NULL);
  85                 exynos_ehci->phy[phy_number] = phy;
  86                 if (IS_ERR(phy)) {
  87                         ret = PTR_ERR(phy);
  88                         if (ret == -EPROBE_DEFER) {
  89                                 of_node_put(child);
  90                                 return ret;
  91                         } else if (ret != -ENOSYS && ret != -ENODEV) {
  92                                 dev_err(dev,
  93                                         "Error retrieving usb2 phy: %d\n", ret);
  94                                 of_node_put(child);
  95                                 return ret;
  96                         }
  97                 }
  98         }
  99
 100         exynos_ehci->legacy_phy = true;
 101         return 0;
 102 }
 103
 104 static int exynos_ehci_phy_enable(struct device *dev)
 105 {
 106         struct usb_hcd *hcd = dev_get_drvdata(dev);
 107         struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
 108         int i;
 109         int ret = 0;
 110
 111         for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
 112                 if (!IS_ERR(exynos_ehci->phy[i]))
 113                         ret = phy_power_on(exynos_ehci->phy[i]);
 114         if (ret)
 115                 for (i--; i >= 0; i--)
 116                         if (!IS_ERR(exynos_ehci->phy[i]))
 117                                 phy_power_off(exynos_ehci->phy[i]);
 118
 119         return ret;
 120 }
 121
 122 static void exynos_ehci_phy_disable(struct device *dev)
 123 {
 124         struct usb_hcd *hcd = dev_get_drvdata(dev);
 125         struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
 126         int i;
 127
 128         for (i = 0; i < PHY_NUMBER; i++)
 129                 if (!IS_ERR(exynos_ehci->phy[i]))
 130                         phy_power_off(exynos_ehci->phy[i]);
 131 }
 132
 133 static void exynos_setup_vbus_gpio(struct device *dev)
 134 {
 135         int err;
 136         int gpio;
 137
 138         if (!dev->of_node)
 139                 return;
 140
 141         gpio = of_get_named_gpio(dev->of_node, "samsung,vbus-gpio", 0);
 142         if (!gpio_is_valid(gpio))
 143                 return;
 144
 145         err = devm_gpio_request_one(dev, gpio, GPIOF_OUT_INIT_HIGH,
 146                                     "ehci_vbus_gpio");
 147         if (err)
 148                 dev_err(dev, "can't request ehci vbus gpio %d", gpio);
 149 }
 150
 151 static int exynos_ehci_probe(struct platform_device *pdev)
 152 {
 153         struct exynos_ehci_hcd *exynos_ehci;
 154         struct usb_hcd *hcd;
 155         struct ehci_hcd *ehci;
 156         struct resource *res;
 157         int irq;
 158         int err;
 159
 160         /*
 161          * Right now device-tree probed devices don't get dma_mask set.
 162          * Since shared usb code relies on it, set it here for now.
 163          * Once we move to full device tree support this will vanish off.
 164          */
 165         err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 166         if (err)
 167                 return err;
 168
 169         exynos_setup_vbus_gpio(&pdev->dev);
 170
 171         hcd = usb_create_hcd(&exynos_ehci_hc_driver,
 172                              &pdev->dev, dev_name(&pdev->dev));
 173         if (!hcd) {
 174                 dev_err(&pdev->dev, "Unable to create HCD\n");
 175                 return -ENOMEM;
 176         }
 177         exynos_ehci = to_exynos_ehci(hcd);
 178
 179         err = exynos_ehci_get_phy(&pdev->dev, exynos_ehci);
 180         if (err)
 181                 goto fail_clk;
 182
 183         exynos_ehci->clk = devm_clk_get(&pdev->dev, "usbhost");
 184
 185         if (IS_ERR(exynos_ehci->clk)) {
 186                 dev_err(&pdev->dev, "Failed to get usbhost clock\n");
 187                 err = PTR_ERR(exynos_ehci->clk);
 188                 goto fail_clk;
 189         }
 190
 191         err = clk_prepare_enable(exynos_ehci->clk);
 192         if (err)
 193                 goto fail_clk;
 194
 195         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 196         hcd->regs = devm_ioremap_resource(&pdev->dev, res);
 197         if (IS_ERR(hcd->regs)) {
 198                 err = PTR_ERR(hcd->regs);
 199                 goto fail_io;
 200         }
 201
 202         hcd->rsrc_start = res->start;
 203         hcd->rsrc_len = resource_size(res);
 204
 205         irq = platform_get_irq(pdev, 0);
 206         if (irq < 0) {
 207                 err = irq;
 208                 goto fail_io;
 209         }
 210
 211         err = exynos_ehci_phy_enable(&pdev->dev);
 212         if (err) {
 213                 dev_err(&pdev->dev, "Failed to enable USB phy\n");
 214                 goto fail_io;
 215         }
 216
 217         ehci = hcd_to_ehci(hcd);
 218         ehci->caps = hcd->regs;
 219
 220         /*
 221          * Workaround: reset of_node pointer to avoid conflict between legacy
 222          * Exynos EHCI port subnodes and generic USB device bindings
 223          */
 224         exynos_ehci->of_node = pdev->dev.of_node;
 225         if (exynos_ehci->legacy_phy)
 226                 pdev->dev.of_node = NULL;
 227
 228         /* DMA burst Enable */
 229         writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
 230
 231         err = usb_add_hcd(hcd, irq, IRQF_SHARED);
 232         if (err) {
 233                 dev_err(&pdev->dev, "Failed to add USB HCD\n");
 234                 goto fail_add_hcd;
 235         }
 236         device_wakeup_enable(hcd->self.controller);
 237
 238         platform_set_drvdata(pdev, hcd);
 239
 240         return 0;
 241
 242 fail_add_hcd:
 243         exynos_ehci_phy_disable(&pdev->dev);
 244         pdev->dev.of_node = exynos_ehci->of_node;
 245 fail_io:
 246         clk_disable_unprepare(exynos_ehci->clk);
 247 fail_clk:
 248         usb_put_hcd(hcd);
 249         return err;
 250 }
 251
 252 static int exynos_ehci_remove(struct platform_device *pdev)
 253 {
 254         struct usb_hcd *hcd = platform_get_drvdata(pdev);
 255         struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
 256
 257         pdev->dev.of_node = exynos_ehci->of_node;
 258
 259         usb_remove_hcd(hcd);
 260
 261         exynos_ehci_phy_disable(&pdev->dev);
 262
 263         clk_disable_unprepare(exynos_ehci->clk);
 264
 265         usb_put_hcd(hcd);
 266
 267         return 0;
 268 }
 269
 270 #ifdef CONFIG_PM
 271 static int exynos_ehci_suspend(struct device *dev)
 272 {
 273         struct usb_hcd *hcd = dev_get_drvdata(dev);
 274         struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
 275
 276         bool do_wakeup = device_may_wakeup(dev);
 277         int rc;
 278
 279         rc = ehci_suspend(hcd, do_wakeup);
 280         if (rc)
 281                 return rc;
 282
 283         exynos_ehci_phy_disable(dev);
 284
 285         clk_disable_unprepare(exynos_ehci->clk);
 286
 287         return rc;
 288 }
 289
 290 static int exynos_ehci_resume(struct device *dev)
 291 {
 292         struct usb_hcd *hcd = dev_get_drvdata(dev);
 293         struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
 294         int ret;
 295
 296         ret = clk_prepare_enable(exynos_ehci->clk);
 297         if (ret)
 298                 return ret;
 299
 300         ret = exynos_ehci_phy_enable(dev);
 301         if (ret) {
 302                 dev_err(dev, "Failed to enable USB phy\n");
 303                 clk_disable_unprepare(exynos_ehci->clk);
 304                 return ret;
 305         }
 306
 307         /* DMA burst Enable */
 308         writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
 309
 310         ehci_resume(hcd, false);
 311         return 0;
 312 }
 313 #else
 314 #define exynos_ehci_suspend     NULL
 315 #define exynos_ehci_resume      NULL
 316 #endif
 317
 318 static const struct dev_pm_ops exynos_ehci_pm_ops = {
 319         .suspend        = exynos_ehci_suspend,
 320         .resume         = exynos_ehci_resume,
 321 };
 322
 323 #ifdef CONFIG_OF
 324 static const struct of_device_id exynos_ehci_match[] = {
 325         { .compatible = "samsung,exynos4210-ehci" },
 326         {},
 327 };
 328 MODULE_DEVICE_TABLE(of, exynos_ehci_match);
 329 #endif
 330
 331 static struct platform_driver exynos_ehci_driver = {
 332         .probe          = exynos_ehci_probe,
 333         .remove         = exynos_ehci_remove,
 334         .shutdown       = usb_hcd_platform_shutdown,
 335         .driver = {
 336                 .name   = "exynos-ehci",
 337                 .pm     = &exynos_ehci_pm_ops,
 338                 .of_match_table = of_match_ptr(exynos_ehci_match),
 339         }
 340 };
 341 static const struct ehci_driver_overrides exynos_overrides __initconst = {
 342         .extra_priv_size = sizeof(struct exynos_ehci_hcd),
 343 };
 344
 345 static int __init ehci_exynos_init(void)
 346 {
 347         if (usb_disabled())
 348                 return -ENODEV;
 349
 350         pr_info("%s: " DRIVER_DESC "\n", hcd_name);
 351         ehci_init_driver(&exynos_ehci_hc_driver, &exynos_overrides);
 352         return platform_driver_register(&exynos_ehci_driver);
 353 }
 354 module_init(ehci_exynos_init);
 355
 356 static void __exit ehci_exynos_cleanup(void)
 357 {
 358         platform_driver_unregister(&exynos_ehci_driver);
 359 }
 360 module_exit(ehci_exynos_cleanup);
 361
 362 MODULE_DESCRIPTION(DRIVER_DESC);
 363 MODULE_ALIAS("platform:exynos-ehci");
 364 MODULE_AUTHOR("Jingoo Han");
 365 MODULE_AUTHOR("Joonyoung Shim");
 366 MODULE_LICENSE("GPL v2");