drivers/usb/host/ohci-at91.c

   1 /*
   2  * OHCI HCD (Host Controller Driver) for USB.
   3  *
   4  *  Copyright (C) 2004 SAN People (Pty) Ltd.
   5  *  Copyright (C) 2005 Thibaut VARENE <varenet@parisc-linux.org>
   6  *
   7  * AT91 Bus Glue
   8  *
   9  * Based on fragments of 2.4 driver by Rick Bronson.
  10  * Based on ohci-omap.c
  11  *
  12  * This file is licenced under the GPL.
  13  */
  14
  15 #include <linux/clk.h>
  16 #include <linux/dma-mapping.h>
  17 #include <linux/of_platform.h>
  18 #include <linux/of_gpio.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/platform_data/atmel.h>
  21 #include <linux/io.h>
  22 #include <linux/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/usb.h>
  25 #include <linux/usb/hcd.h>
  26
  27 #include "ohci.h"
  28
  29 #define valid_port(index)       ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS)
  30 #define at91_for_each_port(index)       \
  31                 for ((index) = 0; (index) < AT91_MAX_USBH_PORTS; (index)++)
  32
  33 /* interface, function and usb clocks; sometimes also an AHB clock */
  34 #define hcd_to_ohci_at91_priv(h) \
  35         ((struct ohci_at91_priv *)hcd_to_ohci(h)->priv)
  36
  37 #define AT91_MAX_USBH_PORTS     3
  38 struct at91_usbh_data {
  39         int vbus_pin[AT91_MAX_USBH_PORTS];      /* port power-control pin */
  40         int overcurrent_pin[AT91_MAX_USBH_PORTS];
  41         u8 ports;                               /* number of ports on root hub */
  42         u8 overcurrent_supported;
  43         u8 vbus_pin_active_low[AT91_MAX_USBH_PORTS];
  44         u8 overcurrent_status[AT91_MAX_USBH_PORTS];
  45         u8 overcurrent_changed[AT91_MAX_USBH_PORTS];
  46 };
  47
  48 struct ohci_at91_priv {
  49         struct clk *iclk;
  50         struct clk *fclk;
  51         struct clk *hclk;
  52         bool clocked;
  53         bool wakeup;            /* Saved wake-up state for resume */
  54 };
  55 /* interface and function clocks; sometimes also an AHB clock */
  56
  57 #define DRIVER_DESC "OHCI Atmel driver"
  58
  59 static const char hcd_name[] = "ohci-atmel";
  60
  61 static struct hc_driver __read_mostly ohci_at91_hc_driver;
  62
  63 static const struct ohci_driver_overrides ohci_at91_drv_overrides __initconst = {
  64         .extra_priv_size = sizeof(struct ohci_at91_priv),
  65 };
  66
  67 extern int usb_disabled(void);
  68
  69 /*-------------------------------------------------------------------------*/
  70
  71 static void at91_start_clock(struct ohci_at91_priv *ohci_at91)
  72 {
  73         if (ohci_at91->clocked)
  74                 return;
  75
  76         clk_set_rate(ohci_at91->fclk, 48000000);
  77         clk_prepare_enable(ohci_at91->hclk);
  78         clk_prepare_enable(ohci_at91->iclk);
  79         clk_prepare_enable(ohci_at91->fclk);
  80         ohci_at91->clocked = true;
  81 }
  82
  83 static void at91_stop_clock(struct ohci_at91_priv *ohci_at91)
  84 {
  85         if (!ohci_at91->clocked)
  86                 return;
  87
  88         clk_disable_unprepare(ohci_at91->fclk);
  89         clk_disable_unprepare(ohci_at91->iclk);
  90         clk_disable_unprepare(ohci_at91->hclk);
  91         ohci_at91->clocked = false;
  92 }
  93
  94 static void at91_start_hc(struct platform_device *pdev)
  95 {
  96         struct usb_hcd *hcd = platform_get_drvdata(pdev);
  97         struct ohci_regs __iomem *regs = hcd->regs;
  98         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
  99
 100         dev_dbg(&pdev->dev, "start\n");
 101
 102         /*
 103          * Start the USB clocks.
 104          */
 105         at91_start_clock(ohci_at91);
 106
 107         /*
 108          * The USB host controller must remain in reset.
 109          */
 110         writel(0, &regs->control);
 111 }
 112
 113 static void at91_stop_hc(struct platform_device *pdev)
 114 {
 115         struct usb_hcd *hcd = platform_get_drvdata(pdev);
 116         struct ohci_regs __iomem *regs = hcd->regs;
 117         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 118
 119         dev_dbg(&pdev->dev, "stop\n");
 120
 121         /*
 122          * Put the USB host controller into reset.
 123          */
 124         writel(0, &regs->control);
 125
 126         /*
 127          * Stop the USB clocks.
 128          */
 129         at91_stop_clock(ohci_at91);
 130 }
 131
 132
 133 /*-------------------------------------------------------------------------*/
 134
 135 static void usb_hcd_at91_remove (struct usb_hcd *, struct platform_device *);
 136
 137 /* configure so an HC device and id are always provided */
 138 /* always called with process context; sleeping is OK */
 139
 140
 141 /**
 142  * usb_hcd_at91_probe - initialize AT91-based HCDs
 143  * Context: !in_interrupt()
 144  *
 145  * Allocates basic resources for this USB host controller, and
 146  * then invokes the start() method for the HCD associated with it
 147  * through the hotplug entry's driver_data.
 148  */
 149 static int usb_hcd_at91_probe(const struct hc_driver *driver,
 150                         struct platform_device *pdev)
 151 {
 152         struct at91_usbh_data *board;
 153         struct ohci_hcd *ohci;
 154         int retval;
 155         struct usb_hcd *hcd;
 156         struct ohci_at91_priv *ohci_at91;
 157         struct device *dev = &pdev->dev;
 158         struct resource *res;
 159         int irq;
 160
 161         irq = platform_get_irq(pdev, 0);
 162         if (irq < 0) {
 163                 dev_dbg(dev, "hcd probe: missing irq resource\n");
 164                 return irq;
 165         }
 166
 167         hcd = usb_create_hcd(driver, dev, "at91");
 168         if (!hcd)
 169                 return -ENOMEM;
 170         ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 171
 172         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 173         hcd->regs = devm_ioremap_resource(dev, res);
 174         if (IS_ERR(hcd->regs)) {
 175                 retval = PTR_ERR(hcd->regs);
 176                 goto err;
 177         }
 178         hcd->rsrc_start = res->start;
 179         hcd->rsrc_len = resource_size(res);
 180
 181         ohci_at91->iclk = devm_clk_get(dev, "ohci_clk");
 182         if (IS_ERR(ohci_at91->iclk)) {
 183                 dev_err(dev, "failed to get ohci_clk\n");
 184                 retval = PTR_ERR(ohci_at91->iclk);
 185                 goto err;
 186         }
 187         ohci_at91->fclk = devm_clk_get(dev, "uhpck");
 188         if (IS_ERR(ohci_at91->fclk)) {
 189                 dev_err(dev, "failed to get uhpck\n");
 190                 retval = PTR_ERR(ohci_at91->fclk);
 191                 goto err;
 192         }
 193         ohci_at91->hclk = devm_clk_get(dev, "hclk");
 194         if (IS_ERR(ohci_at91->hclk)) {
 195                 dev_err(dev, "failed to get hclk\n");
 196                 retval = PTR_ERR(ohci_at91->hclk);
 197                 goto err;
 198         }
 199
 200         board = hcd->self.controller->platform_data;
 201         ohci = hcd_to_ohci(hcd);
 202         ohci->num_ports = board->ports;
 203         at91_start_hc(pdev);
 204
 205         retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
 206         if (retval == 0) {
 207                 device_wakeup_enable(hcd->self.controller);
 208                 return retval;
 209         }
 210
 211         /* Error handling */
 212         at91_stop_hc(pdev);
 213
 214  err:
 215         usb_put_hcd(hcd);
 216         return retval;
 217 }
 218
 219
 220 /* may be called with controller, bus, and devices active */
 221
 222 /**
 223  * usb_hcd_at91_remove - shutdown processing for AT91-based HCDs
 224  * @dev: USB Host Controller being removed
 225  * Context: !in_interrupt()
 226  *
 227  * Reverses the effect of usb_hcd_at91_probe(), first invoking
 228  * the HCD's stop() method.  It is always called from a thread
 229  * context, "rmmod" or something similar.
 230  *
 231  */
 232 static void usb_hcd_at91_remove(struct usb_hcd *hcd,
 233                                 struct platform_device *pdev)
 234 {
 235         usb_remove_hcd(hcd);
 236         at91_stop_hc(pdev);
 237         usb_put_hcd(hcd);
 238 }
 239
 240 /*-------------------------------------------------------------------------*/
 241 static void ohci_at91_usb_set_power(struct at91_usbh_data *pdata, int port, int enable)
 242 {
 243         if (!valid_port(port))
 244                 return;
 245
 246         if (!gpio_is_valid(pdata->vbus_pin[port]))
 247                 return;
 248
 249         gpio_set_value(pdata->vbus_pin[port],
 250                        pdata->vbus_pin_active_low[port] ^ enable);
 251 }
 252
 253 static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
 254 {
 255         if (!valid_port(port))
 256                 return -EINVAL;
 257
 258         if (!gpio_is_valid(pdata->vbus_pin[port]))
 259                 return -EINVAL;
 260
 261         return gpio_get_value(pdata->vbus_pin[port]) ^
 262                 pdata->vbus_pin_active_low[port];
 263 }
 264
 265 /*
 266  * Update the status data from the hub with the over-current indicator change.
 267  */
 268 static int ohci_at91_hub_status_data(struct usb_hcd *hcd, char *buf)
 269 {
 270         struct at91_usbh_data *pdata = hcd->self.controller->platform_data;
 271         int length = ohci_hub_status_data(hcd, buf);
 272         int port;
 273
 274         at91_for_each_port(port) {
 275                 if (pdata->overcurrent_changed[port]) {
 276                         if (!length)
 277                                 length = 1;
 278                         buf[0] |= 1 << (port + 1);
 279                 }
 280         }
 281
 282         return length;
 283 }
 284
 285 /*
 286  * Look at the control requests to the root hub and see if we need to override.
 287  */
 288 static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 289                                  u16 wIndex, char *buf, u16 wLength)
 290 {
 291         struct at91_usbh_data *pdata = dev_get_platdata(hcd->self.controller);
 292         struct usb_hub_descriptor *desc;
 293         int ret = -EINVAL;
 294         u32 *data = (u32 *)buf;
 295
 296         dev_dbg(hcd->self.controller,
 297                 "ohci_at91_hub_control(%p,0x%04x,0x%04x,0x%04x,%p,%04x)\n",
 298                 hcd, typeReq, wValue, wIndex, buf, wLength);
 299
 300         wIndex--;
 301
 302         switch (typeReq) {
 303         case SetPortFeature:
 304                 if (wValue == USB_PORT_FEAT_POWER) {
 305                         dev_dbg(hcd->self.controller, "SetPortFeat: POWER\n");
 306                         if (valid_port(wIndex)) {
 307                                 ohci_at91_usb_set_power(pdata, wIndex, 1);
 308                                 ret = 0;
 309                         }
 310
 311                         goto out;
 312                 }
 313                 break;
 314
 315         case ClearPortFeature:
 316                 switch (wValue) {
 317                 case USB_PORT_FEAT_C_OVER_CURRENT:
 318                         dev_dbg(hcd->self.controller,
 319                                 "ClearPortFeature: C_OVER_CURRENT\n");
 320
 321                         if (valid_port(wIndex)) {
 322                                 pdata->overcurrent_changed[wIndex] = 0;
 323                                 pdata->overcurrent_status[wIndex] = 0;
 324                         }
 325
 326                         goto out;
 327
 328                 case USB_PORT_FEAT_OVER_CURRENT:
 329                         dev_dbg(hcd->self.controller,
 330                                 "ClearPortFeature: OVER_CURRENT\n");
 331
 332                         if (valid_port(wIndex))
 333                                 pdata->overcurrent_status[wIndex] = 0;
 334
 335                         goto out;
 336
 337                 case USB_PORT_FEAT_POWER:
 338                         dev_dbg(hcd->self.controller,
 339                                 "ClearPortFeature: POWER\n");
 340
 341                         if (valid_port(wIndex)) {
 342                                 ohci_at91_usb_set_power(pdata, wIndex, 0);
 343                                 return 0;
 344                         }
 345                 }
 346                 break;
 347         }
 348
 349         ret = ohci_hub_control(hcd, typeReq, wValue, wIndex + 1, buf, wLength);
 350         if (ret)
 351                 goto out;
 352
 353         switch (typeReq) {
 354         case GetHubDescriptor:
 355
 356                 /* update the hub's descriptor */
 357
 358                 desc = (struct usb_hub_descriptor *)buf;
 359
 360                 dev_dbg(hcd->self.controller, "wHubCharacteristics 0x%04x\n",
 361                         desc->wHubCharacteristics);
 362
 363                 /* remove the old configurations for power-switching, and
 364                  * over-current protection, and insert our new configuration
 365                  */
 366
 367                 desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_LPSM);
 368                 desc->wHubCharacteristics |=
 369                         cpu_to_le16(HUB_CHAR_INDV_PORT_LPSM);
 370
 371                 if (pdata->overcurrent_supported) {
 372                         desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_OCPM);
 373                         desc->wHubCharacteristics |=
 374                                 cpu_to_le16(HUB_CHAR_INDV_PORT_OCPM);
 375                 }
 376
 377                 dev_dbg(hcd->self.controller, "wHubCharacteristics after 0x%04x\n",
 378                         desc->wHubCharacteristics);
 379
 380                 return ret;
 381
 382         case GetPortStatus:
 383                 /* check port status */
 384
 385                 dev_dbg(hcd->self.controller, "GetPortStatus(%d)\n", wIndex);
 386
 387                 if (valid_port(wIndex)) {
 388                         if (!ohci_at91_usb_get_power(pdata, wIndex))
 389                                 *data &= ~cpu_to_le32(RH_PS_PPS);
 390
 391                         if (pdata->overcurrent_changed[wIndex])
 392                                 *data |= cpu_to_le32(RH_PS_OCIC);
 393
 394                         if (pdata->overcurrent_status[wIndex])
 395                                 *data |= cpu_to_le32(RH_PS_POCI);
 396                 }
 397         }
 398
 399  out:
 400         return ret;
 401 }
 402
 403 /*-------------------------------------------------------------------------*/
 404
 405 static irqreturn_t ohci_hcd_at91_overcurrent_irq(int irq, void *data)
 406 {
 407         struct platform_device *pdev = data;
 408         struct at91_usbh_data *pdata = dev_get_platdata(&pdev->dev);
 409         int val, gpio, port;
 410
 411         /* From the GPIO notifying the over-current situation, find
 412          * out the corresponding port */
 413         at91_for_each_port(port) {
 414                 if (gpio_is_valid(pdata->overcurrent_pin[port]) &&
 415                                 gpio_to_irq(pdata->overcurrent_pin[port]) == irq) {
 416                         gpio = pdata->overcurrent_pin[port];
 417                         break;
 418                 }
 419         }
 420
 421         if (port == AT91_MAX_USBH_PORTS) {
 422                 dev_err(& pdev->dev, "overcurrent interrupt from unknown GPIO\n");
 423                 return IRQ_HANDLED;
 424         }
 425
 426         val = gpio_get_value(gpio);
 427
 428         /* When notified of an over-current situation, disable power
 429            on the corresponding port, and mark this port in
 430            over-current. */
 431         if (!val) {
 432                 ohci_at91_usb_set_power(pdata, port, 0);
 433                 pdata->overcurrent_status[port]  = 1;
 434                 pdata->overcurrent_changed[port] = 1;
 435         }
 436
 437         dev_dbg(& pdev->dev, "overcurrent situation %s\n",
 438                 val ? "exited" : "notified");
 439
 440         return IRQ_HANDLED;
 441 }
 442
 443 static const struct of_device_id at91_ohci_dt_ids[] = {
 444         { .compatible = "atmel,at91rm9200-ohci" },
 445         { /* sentinel */ }
 446 };
 447
 448 MODULE_DEVICE_TABLE(of, at91_ohci_dt_ids);
 449
 450 /*-------------------------------------------------------------------------*/
 451
 452 static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
 453 {
 454         struct device_node *np = pdev->dev.of_node;
 455         struct at91_usbh_data   *pdata;
 456         int                     i;
 457         int                     gpio;
 458         int                     ret;
 459         enum of_gpio_flags      flags;
 460         u32                     ports;
 461
 462         /* Right now device-tree probed devices don't get dma_mask set.
 463          * Since shared usb code relies on it, set it here for now.
 464          * Once we have dma capability bindings this can go away.
 465          */
 466         ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 467         if (ret)
 468                 return ret;
 469
 470         pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 471         if (!pdata)
 472                 return -ENOMEM;
 473
 474         pdev->dev.platform_data = pdata;
 475
 476         if (!of_property_read_u32(np, "num-ports", &ports))
 477                 pdata->ports = ports;
 478
 479         at91_for_each_port(i) {
 480                 /*
 481                  * do not configure PIO if not in relation with
 482                  * real USB port on board
 483                  */
 484                 if (i >= pdata->ports) {
 485                         pdata->vbus_pin[i] = -EINVAL;
 486                         pdata->overcurrent_pin[i] = -EINVAL;
 487                         continue;
 488                 }
 489
 490                 gpio = of_get_named_gpio_flags(np, "atmel,vbus-gpio", i,
 491                                                &flags);
 492                 pdata->vbus_pin[i] = gpio;
 493                 if (!gpio_is_valid(gpio))
 494                         continue;
 495                 pdata->vbus_pin_active_low[i] = flags & OF_GPIO_ACTIVE_LOW;
 496
 497                 ret = gpio_request(gpio, "ohci_vbus");
 498                 if (ret) {
 499                         dev_err(&pdev->dev,
 500                                 "can't request vbus gpio %d\n", gpio);
 501                         continue;
 502                 }
 503                 ret = gpio_direction_output(gpio,
 504                                         !pdata->vbus_pin_active_low[i]);
 505                 if (ret) {
 506                         dev_err(&pdev->dev,
 507                                 "can't put vbus gpio %d as output %d\n",
 508                                 gpio, !pdata->vbus_pin_active_low[i]);
 509                         gpio_free(gpio);
 510                         continue;
 511                 }
 512
 513                 ohci_at91_usb_set_power(pdata, i, 1);
 514         }
 515
 516         at91_for_each_port(i) {
 517                 if (i >= pdata->ports)
 518                         break;
 519
 520                 pdata->overcurrent_pin[i] =
 521                         of_get_named_gpio_flags(np, "atmel,oc-gpio", i, &flags);
 522
 523                 if (!gpio_is_valid(pdata->overcurrent_pin[i]))
 524                         continue;
 525                 gpio = pdata->overcurrent_pin[i];
 526
 527                 ret = gpio_request(gpio, "ohci_overcurrent");
 528                 if (ret) {
 529                         dev_err(&pdev->dev,
 530                                 "can't request overcurrent gpio %d\n",
 531                                 gpio);
 532                         continue;
 533                 }
 534
 535                 ret = gpio_direction_input(gpio);
 536                 if (ret) {
 537                         dev_err(&pdev->dev,
 538                                 "can't configure overcurrent gpio %d as input\n",
 539                                 gpio);
 540                         gpio_free(gpio);
 541                         continue;
 542                 }
 543
 544                 ret = request_irq(gpio_to_irq(gpio),
 545                                   ohci_hcd_at91_overcurrent_irq,
 546                                   IRQF_SHARED, "ohci_overcurrent", pdev);
 547                 if (ret) {
 548                         gpio_free(gpio);
 549                         dev_err(&pdev->dev,
 550                                 "can't get gpio IRQ for overcurrent\n");
 551                 }
 552         }
 553
 554         device_init_wakeup(&pdev->dev, 1);
 555         return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
 556 }
 557
 558 static int ohci_hcd_at91_drv_remove(struct platform_device *pdev)
 559 {
 560         struct at91_usbh_data   *pdata = dev_get_platdata(&pdev->dev);
 561         int                     i;
 562
 563         if (pdata) {
 564                 at91_for_each_port(i) {
 565                         if (!gpio_is_valid(pdata->vbus_pin[i]))
 566                                 continue;
 567                         ohci_at91_usb_set_power(pdata, i, 0);
 568                         gpio_free(pdata->vbus_pin[i]);
 569                 }
 570
 571                 at91_for_each_port(i) {
 572                         if (!gpio_is_valid(pdata->overcurrent_pin[i]))
 573                                 continue;
 574                         free_irq(gpio_to_irq(pdata->overcurrent_pin[i]), pdev);
 575                         gpio_free(pdata->overcurrent_pin[i]);
 576                 }
 577         }
 578
 579         device_init_wakeup(&pdev->dev, 0);
 580         usb_hcd_at91_remove(platform_get_drvdata(pdev), pdev);
 581         return 0;
 582 }
 583
 584 static int __maybe_unused
 585 ohci_hcd_at91_drv_suspend(struct device *dev)
 586 {
 587         struct usb_hcd  *hcd = dev_get_drvdata(dev);
 588         struct ohci_hcd *ohci = hcd_to_ohci(hcd);
 589         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 590         int             ret;
 591
 592         /*
 593          * Disable wakeup if we are going to sleep with slow clock mode
 594          * enabled.
 595          */
 596         ohci_at91->wakeup = device_may_wakeup(dev)
 597                         && !at91_suspend_entering_slow_clock();
 598
 599         if (ohci_at91->wakeup)
 600                 enable_irq_wake(hcd->irq);
 601
 602         ret = ohci_suspend(hcd, ohci_at91->wakeup);
 603         if (ret) {
 604                 if (ohci_at91->wakeup)
 605                         disable_irq_wake(hcd->irq);
 606                 return ret;
 607         }
 608         /*
 609          * The integrated transceivers seem unable to notice disconnect,
 610          * reconnect, or wakeup without the 48 MHz clock active.  so for
 611          * correctness, always discard connection state (using reset).
 612          *
 613          * REVISIT: some boards will be able to turn VBUS off...
 614          */
 615         if (!ohci_at91->wakeup) {
 616                 ohci->hc_control = ohci_readl(ohci, &ohci->regs->control);
 617                 ohci->hc_control &= OHCI_CTRL_RWC;
 618                 ohci_writel(ohci, ohci->hc_control, &ohci->regs->control);
 619                 ohci->rh_state = OHCI_RH_HALTED;
 620
 621                 /* flush the writes */
 622                 (void) ohci_readl (ohci, &ohci->regs->control);
 623                 at91_stop_clock(ohci_at91);
 624         }
 625
 626         return ret;
 627 }
 628
 629 static int __maybe_unused
 630 ohci_hcd_at91_drv_resume(struct device *dev)
 631 {
 632         struct usb_hcd  *hcd = dev_get_drvdata(dev);
 633         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 634
 635         if (ohci_at91->wakeup)
 636                 disable_irq_wake(hcd->irq);
 637
 638         at91_start_clock(ohci_at91);
 639
 640         ohci_resume(hcd, false);
 641         return 0;
 642 }
 643
 644 static SIMPLE_DEV_PM_OPS(ohci_hcd_at91_pm_ops, ohci_hcd_at91_drv_suspend,
 645                                         ohci_hcd_at91_drv_resume);
 646
 647 static struct platform_driver ohci_hcd_at91_driver = {
 648         .probe          = ohci_hcd_at91_drv_probe,
 649         .remove         = ohci_hcd_at91_drv_remove,
 650         .shutdown       = usb_hcd_platform_shutdown,
 651         .driver         = {
 652                 .name   = "at91_ohci",
 653                 .pm     = &ohci_hcd_at91_pm_ops,
 654                 .of_match_table = at91_ohci_dt_ids,
 655         },
 656 };
 657
 658 static int __init ohci_at91_init(void)
 659 {
 660         if (usb_disabled())
 661                 return -ENODEV;
 662
 663         pr_info("%s: " DRIVER_DESC "\n", hcd_name);
 664         ohci_init_driver(&ohci_at91_hc_driver, &ohci_at91_drv_overrides);
 665
 666         /*
 667          * The Atmel HW has some unusual quirks, which require Atmel-specific
 668          * workarounds. We override certain hc_driver functions here to
 669          * achieve that. We explicitly do not enhance ohci_driver_overrides to
 670          * allow this more easily, since this is an unusual case, and we don't
 671          * want to encourage others to override these functions by making it
 672          * too easy.
 673          */
 674
 675         ohci_at91_hc_driver.hub_status_data     = ohci_at91_hub_status_data;
 676         ohci_at91_hc_driver.hub_control         = ohci_at91_hub_control;
 677
 678         return platform_driver_register(&ohci_hcd_at91_driver);
 679 }
 680 module_init(ohci_at91_init);
 681
 682 static void __exit ohci_at91_cleanup(void)
 683 {
 684         platform_driver_unregister(&ohci_hcd_at91_driver);
 685 }
 686 module_exit(ohci_at91_cleanup);
 687
 688 MODULE_DESCRIPTION(DRIVER_DESC);
 689 MODULE_LICENSE("GPL");
 690 MODULE_ALIAS("platform:at91_ohci");