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 <asm/gpio.h>
  28
  29 #include "ohci.h"
  30
  31 #define valid_port(index)       ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS)
  32 #define at91_for_each_port(index)       \
  33                 for ((index) = 0; (index) < AT91_MAX_USBH_PORTS; (index)++)
  34
  35 /* interface, function and usb clocks; sometimes also an AHB clock */
  36 static struct clk *iclk, *fclk, *uclk, *hclk;
  37 /* interface and function clocks; sometimes also an AHB clock */
  38
  39 #define DRIVER_DESC "OHCI Atmel driver"
  40
  41 static const char hcd_name[] = "ohci-atmel";
  42
  43 static struct hc_driver __read_mostly ohci_at91_hc_driver;
  44 static int clocked;
  45
  46 extern int usb_disabled(void);
  47
  48 /*-------------------------------------------------------------------------*/
  49
  50 static void at91_start_clock(void)
  51 {
  52         if (IS_ENABLED(CONFIG_COMMON_CLK)) {
  53                 clk_set_rate(uclk, 48000000);
  54                 clk_prepare_enable(uclk);
  55         }
  56         clk_prepare_enable(hclk);
  57         clk_prepare_enable(iclk);
  58         clk_prepare_enable(fclk);
  59         clocked = 1;
  60 }
  61
  62 static void at91_stop_clock(void)
  63 {
  64         clk_disable_unprepare(fclk);
  65         clk_disable_unprepare(iclk);
  66         clk_disable_unprepare(hclk);
  67         if (IS_ENABLED(CONFIG_COMMON_CLK))
  68                 clk_disable_unprepare(uclk);
  69         clocked = 0;
  70 }
  71
  72 static void at91_start_hc(struct platform_device *pdev)
  73 {
  74         struct usb_hcd *hcd = platform_get_drvdata(pdev);
  75         struct ohci_regs __iomem *regs = hcd->regs;
  76
  77         dev_dbg(&pdev->dev, "start\n");
  78
  79         /*
  80          * Start the USB clocks.
  81          */
  82         at91_start_clock();
  83
  84         /*
  85          * The USB host controller must remain in reset.
  86          */
  87         writel(0, &regs->control);
  88 }
  89
  90 static void at91_stop_hc(struct platform_device *pdev)
  91 {
  92         struct usb_hcd *hcd = platform_get_drvdata(pdev);
  93         struct ohci_regs __iomem *regs = hcd->regs;
  94
  95         dev_dbg(&pdev->dev, "stop\n");
  96
  97         /*
  98          * Put the USB host controller into reset.
  99          */
 100         writel(0, &regs->control);
 101
 102         /*
 103          * Stop the USB clocks.
 104          */
 105         at91_stop_clock();
 106 }
 107
 108
 109 /*-------------------------------------------------------------------------*/
 110
 111 static void usb_hcd_at91_remove (struct usb_hcd *, struct platform_device *);
 112
 113 /* configure so an HC device and id are always provided */
 114 /* always called with process context; sleeping is OK */
 115
 116
 117 /**
 118  * usb_hcd_at91_probe - initialize AT91-based HCDs
 119  * Context: !in_interrupt()
 120  *
 121  * Allocates basic resources for this USB host controller, and
 122  * then invokes the start() method for the HCD associated with it
 123  * through the hotplug entry's driver_data.
 124  */
 125 static int usb_hcd_at91_probe(const struct hc_driver *driver,
 126                         struct platform_device *pdev)
 127 {
 128         struct at91_usbh_data *board;
 129         struct ohci_hcd *ohci;
 130         int retval;
 131         struct usb_hcd *hcd = NULL;
 132         struct device *dev = &pdev->dev;
 133         struct resource *res;
 134         int irq;
 135
 136         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 137         if (!res) {
 138                 dev_dbg(dev, "hcd probe: missing memory resource\n");
 139                 return -ENXIO;
 140         }
 141
 142         irq = platform_get_irq(pdev, 0);
 143         if (irq < 0) {
 144                 dev_dbg(dev, "hcd probe: missing irq resource\n");
 145                 return irq;
 146         }
 147
 148         hcd = usb_create_hcd(driver, dev, "at91");
 149         if (!hcd)
 150                 return -ENOMEM;
 151         hcd->rsrc_start = res->start;
 152         hcd->rsrc_len = resource_size(res);
 153
 154         hcd->regs = devm_ioremap_resource(dev, res);
 155         if (IS_ERR(hcd->regs)) {
 156                 retval = PTR_ERR(hcd->regs);
 157                 goto err;
 158         }
 159
 160         iclk = devm_clk_get(dev, "ohci_clk");
 161         if (IS_ERR(iclk)) {
 162                 dev_err(dev, "failed to get ohci_clk\n");
 163                 retval = PTR_ERR(iclk);
 164                 goto err;
 165         }
 166         fclk = devm_clk_get(dev, "uhpck");
 167         if (IS_ERR(fclk)) {
 168                 dev_err(dev, "failed to get uhpck\n");
 169                 retval = PTR_ERR(fclk);
 170                 goto err;
 171         }
 172         hclk = devm_clk_get(dev, "hclk");
 173         if (IS_ERR(hclk)) {
 174                 dev_err(dev, "failed to get hclk\n");
 175                 retval = PTR_ERR(hclk);
 176                 goto err;
 177         }
 178         if (IS_ENABLED(CONFIG_COMMON_CLK)) {
 179                 uclk = devm_clk_get(dev, "usb_clk");
 180                 if (IS_ERR(uclk)) {
 181                         dev_err(dev, "failed to get uclk\n");
 182                         retval = PTR_ERR(uclk);
 183                         goto err;
 184                 }
 185         }
 186
 187         board = hcd->self.controller->platform_data;
 188         ohci = hcd_to_ohci(hcd);
 189         ohci->num_ports = board->ports;
 190         at91_start_hc(pdev);
 191
 192         retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
 193         if (retval == 0) {
 194                 device_wakeup_enable(hcd->self.controller);
 195                 return retval;
 196         }
 197
 198         /* Error handling */
 199         at91_stop_hc(pdev);
 200
 201  err:
 202         usb_put_hcd(hcd);
 203         return retval;
 204 }
 205
 206
 207 /* may be called with controller, bus, and devices active */
 208
 209 /**
 210  * usb_hcd_at91_remove - shutdown processing for AT91-based HCDs
 211  * @dev: USB Host Controller being removed
 212  * Context: !in_interrupt()
 213  *
 214  * Reverses the effect of usb_hcd_at91_probe(), first invoking
 215  * the HCD's stop() method.  It is always called from a thread
 216  * context, "rmmod" or something similar.
 217  *
 218  */
 219 static void usb_hcd_at91_remove(struct usb_hcd *hcd,
 220                                 struct platform_device *pdev)
 221 {
 222         usb_remove_hcd(hcd);
 223         at91_stop_hc(pdev);
 224         usb_put_hcd(hcd);
 225 }
 226
 227 /*-------------------------------------------------------------------------*/
 228 static void ohci_at91_usb_set_power(struct at91_usbh_data *pdata, int port, int enable)
 229 {
 230         if (!valid_port(port))
 231                 return;
 232
 233         if (!gpio_is_valid(pdata->vbus_pin[port]))
 234                 return;
 235
 236         gpio_set_value(pdata->vbus_pin[port],
 237                        pdata->vbus_pin_active_low[port] ^ enable);
 238 }
 239
 240 static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
 241 {
 242         if (!valid_port(port))
 243                 return -EINVAL;
 244
 245         if (!gpio_is_valid(pdata->vbus_pin[port]))
 246                 return -EINVAL;
 247
 248         return gpio_get_value(pdata->vbus_pin[port]) ^
 249                 pdata->vbus_pin_active_low[port];
 250 }
 251
 252 /*
 253  * Update the status data from the hub with the over-current indicator change.
 254  */
 255 static int ohci_at91_hub_status_data(struct usb_hcd *hcd, char *buf)
 256 {
 257         struct at91_usbh_data *pdata = hcd->self.controller->platform_data;
 258         int length = ohci_hub_status_data(hcd, buf);
 259         int port;
 260
 261         at91_for_each_port(port) {
 262                 if (pdata->overcurrent_changed[port]) {
 263                         if (!length)
 264                                 length = 1;
 265                         buf[0] |= 1 << (port + 1);
 266                 }
 267         }
 268
 269         return length;
 270 }
 271
 272 /*
 273  * Look at the control requests to the root hub and see if we need to override.
 274  */
 275 static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 276                                  u16 wIndex, char *buf, u16 wLength)
 277 {
 278         struct at91_usbh_data *pdata = dev_get_platdata(hcd->self.controller);
 279         struct usb_hub_descriptor *desc;
 280         int ret = -EINVAL;
 281         u32 *data = (u32 *)buf;
 282
 283         dev_dbg(hcd->self.controller,
 284                 "ohci_at91_hub_control(%p,0x%04x,0x%04x,0x%04x,%p,%04x)\n",
 285                 hcd, typeReq, wValue, wIndex, buf, wLength);
 286
 287         wIndex--;
 288
 289         switch (typeReq) {
 290         case SetPortFeature:
 291                 if (wValue == USB_PORT_FEAT_POWER) {
 292                         dev_dbg(hcd->self.controller, "SetPortFeat: POWER\n");
 293                         if (valid_port(wIndex)) {
 294                                 ohci_at91_usb_set_power(pdata, wIndex, 1);
 295                                 ret = 0;
 296                         }
 297
 298                         goto out;
 299                 }
 300                 break;
 301
 302         case ClearPortFeature:
 303                 switch (wValue) {
 304                 case USB_PORT_FEAT_C_OVER_CURRENT:
 305                         dev_dbg(hcd->self.controller,
 306                                 "ClearPortFeature: C_OVER_CURRENT\n");
 307
 308                         if (valid_port(wIndex)) {
 309                                 pdata->overcurrent_changed[wIndex] = 0;
 310                                 pdata->overcurrent_status[wIndex] = 0;
 311                         }
 312
 313                         goto out;
 314
 315                 case USB_PORT_FEAT_OVER_CURRENT:
 316                         dev_dbg(hcd->self.controller,
 317                                 "ClearPortFeature: OVER_CURRENT\n");
 318
 319                         if (valid_port(wIndex))
 320                                 pdata->overcurrent_status[wIndex] = 0;
 321
 322                         goto out;
 323
 324                 case USB_PORT_FEAT_POWER:
 325                         dev_dbg(hcd->self.controller,
 326                                 "ClearPortFeature: POWER\n");
 327
 328                         if (valid_port(wIndex)) {
 329                                 ohci_at91_usb_set_power(pdata, wIndex, 0);
 330                                 return 0;
 331                         }
 332                 }
 333                 break;
 334         }
 335
 336         ret = ohci_hub_control(hcd, typeReq, wValue, wIndex + 1, buf, wLength);
 337         if (ret)
 338                 goto out;
 339
 340         switch (typeReq) {
 341         case GetHubDescriptor:
 342
 343                 /* update the hub's descriptor */
 344
 345                 desc = (struct usb_hub_descriptor *)buf;
 346
 347                 dev_dbg(hcd->self.controller, "wHubCharacteristics 0x%04x\n",
 348                         desc->wHubCharacteristics);
 349
 350                 /* remove the old configurations for power-switching, and
 351                  * over-current protection, and insert our new configuration
 352                  */
 353
 354                 desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_LPSM);
 355                 desc->wHubCharacteristics |= cpu_to_le16(0x0001);
 356
 357                 if (pdata->overcurrent_supported) {
 358                         desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_OCPM);
 359                         desc->wHubCharacteristics |=  cpu_to_le16(0x0008|0x0001);
 360                 }
 361
 362                 dev_dbg(hcd->self.controller, "wHubCharacteristics after 0x%04x\n",
 363                         desc->wHubCharacteristics);
 364
 365                 return ret;
 366
 367         case GetPortStatus:
 368                 /* check port status */
 369
 370                 dev_dbg(hcd->self.controller, "GetPortStatus(%d)\n", wIndex);
 371
 372                 if (valid_port(wIndex)) {
 373                         if (!ohci_at91_usb_get_power(pdata, wIndex))
 374                                 *data &= ~cpu_to_le32(RH_PS_PPS);
 375
 376                         if (pdata->overcurrent_changed[wIndex])
 377                                 *data |= cpu_to_le32(RH_PS_OCIC);
 378
 379                         if (pdata->overcurrent_status[wIndex])
 380                                 *data |= cpu_to_le32(RH_PS_POCI);
 381                 }
 382         }
 383
 384  out:
 385         return ret;
 386 }
 387
 388 /*-------------------------------------------------------------------------*/
 389
 390 static irqreturn_t ohci_hcd_at91_overcurrent_irq(int irq, void *data)
 391 {
 392         struct platform_device *pdev = data;
 393         struct at91_usbh_data *pdata = dev_get_platdata(&pdev->dev);
 394         int val, gpio, port;
 395
 396         /* From the GPIO notifying the over-current situation, find
 397          * out the corresponding port */
 398         at91_for_each_port(port) {
 399                 if (gpio_is_valid(pdata->overcurrent_pin[port]) &&
 400                                 gpio_to_irq(pdata->overcurrent_pin[port]) == irq) {
 401                         gpio = pdata->overcurrent_pin[port];
 402                         break;
 403                 }
 404         }
 405
 406         if (port == AT91_MAX_USBH_PORTS) {
 407                 dev_err(& pdev->dev, "overcurrent interrupt from unknown GPIO\n");
 408                 return IRQ_HANDLED;
 409         }
 410
 411         val = gpio_get_value(gpio);
 412
 413         /* When notified of an over-current situation, disable power
 414            on the corresponding port, and mark this port in
 415            over-current. */
 416         if (!val) {
 417                 ohci_at91_usb_set_power(pdata, port, 0);
 418                 pdata->overcurrent_status[port]  = 1;
 419                 pdata->overcurrent_changed[port] = 1;
 420         }
 421
 422         dev_dbg(& pdev->dev, "overcurrent situation %s\n",
 423                 val ? "exited" : "notified");
 424
 425         return IRQ_HANDLED;
 426 }
 427
 428 #ifdef CONFIG_OF
 429 static const struct of_device_id at91_ohci_dt_ids[] = {
 430         { .compatible = "atmel,at91rm9200-ohci" },
 431         { /* sentinel */ }
 432 };
 433
 434 MODULE_DEVICE_TABLE(of, at91_ohci_dt_ids);
 435
 436 static int ohci_at91_of_init(struct platform_device *pdev)
 437 {
 438         struct device_node *np = pdev->dev.of_node;
 439         int i, gpio, ret;
 440         enum of_gpio_flags flags;
 441         struct at91_usbh_data   *pdata;
 442         u32 ports;
 443
 444         if (!np)
 445                 return 0;
 446
 447         /* Right now device-tree probed devices don't get dma_mask set.
 448          * Since shared usb code relies on it, set it here for now.
 449          * Once we have dma capability bindings this can go away.
 450          */
 451         ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 452         if (ret)
 453                 return ret;
 454
 455         pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 456         if (!pdata)
 457                 return -ENOMEM;
 458
 459         if (!of_property_read_u32(np, "num-ports", &ports))
 460                 pdata->ports = ports;
 461
 462         at91_for_each_port(i) {
 463                 gpio = of_get_named_gpio_flags(np, "atmel,vbus-gpio", i, &flags);
 464                 pdata->vbus_pin[i] = gpio;
 465                 if (!gpio_is_valid(gpio))
 466                         continue;
 467                 pdata->vbus_pin_active_low[i] = flags & OF_GPIO_ACTIVE_LOW;
 468         }
 469
 470         at91_for_each_port(i)
 471                 pdata->overcurrent_pin[i] =
 472                         of_get_named_gpio_flags(np, "atmel,oc-gpio", i, &flags);
 473
 474         pdev->dev.platform_data = pdata;
 475
 476         return 0;
 477 }
 478 #else
 479 static int ohci_at91_of_init(struct platform_device *pdev)
 480 {
 481         return 0;
 482 }
 483 #endif
 484
 485 /*-------------------------------------------------------------------------*/
 486
 487 static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
 488 {
 489         struct at91_usbh_data   *pdata;
 490         int                     i;
 491         int                     gpio;
 492         int                     ret;
 493
 494         ret = ohci_at91_of_init(pdev);
 495         if (ret)
 496                 return ret;
 497
 498         pdata = dev_get_platdata(&pdev->dev);
 499
 500         if (pdata) {
 501                 at91_for_each_port(i) {
 502                         /*
 503                          * do not configure PIO if not in relation with
 504                          * real USB port on board
 505                          */
 506                         if (i >= pdata->ports) {
 507                                 pdata->vbus_pin[i] = -EINVAL;
 508                                 pdata->overcurrent_pin[i] = -EINVAL;
 509                                 break;
 510                         }
 511
 512                         if (!gpio_is_valid(pdata->vbus_pin[i]))
 513                                 continue;
 514                         gpio = pdata->vbus_pin[i];
 515
 516                         ret = gpio_request(gpio, "ohci_vbus");
 517                         if (ret) {
 518                                 dev_err(&pdev->dev,
 519                                         "can't request vbus gpio %d\n", gpio);
 520                                 continue;
 521                         }
 522                         ret = gpio_direction_output(gpio,
 523                                                 !pdata->vbus_pin_active_low[i]);
 524                         if (ret) {
 525                                 dev_err(&pdev->dev,
 526                                         "can't put vbus gpio %d as output %d\n",
 527                                         gpio, !pdata->vbus_pin_active_low[i]);
 528                                 gpio_free(gpio);
 529                                 continue;
 530                         }
 531
 532                         ohci_at91_usb_set_power(pdata, i, 1);
 533                 }
 534
 535                 at91_for_each_port(i) {
 536                         if (!gpio_is_valid(pdata->overcurrent_pin[i]))
 537                                 continue;
 538                         gpio = pdata->overcurrent_pin[i];
 539
 540                         ret = gpio_request(gpio, "ohci_overcurrent");
 541                         if (ret) {
 542                                 dev_err(&pdev->dev,
 543                                         "can't request overcurrent gpio %d\n",
 544                                         gpio);
 545                                 continue;
 546                         }
 547
 548                         ret = gpio_direction_input(gpio);
 549                         if (ret) {
 550                                 dev_err(&pdev->dev,
 551                                         "can't configure overcurrent gpio %d as input\n",
 552                                         gpio);
 553                                 gpio_free(gpio);
 554                                 continue;
 555                         }
 556
 557                         ret = request_irq(gpio_to_irq(gpio),
 558                                           ohci_hcd_at91_overcurrent_irq,
 559                                           IRQF_SHARED, "ohci_overcurrent", pdev);
 560                         if (ret) {
 561                                 gpio_free(gpio);
 562                                 dev_err(&pdev->dev,
 563                                         "can't get gpio IRQ for overcurrent\n");
 564                         }
 565                 }
 566         }
 567
 568         device_init_wakeup(&pdev->dev, 1);
 569         return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
 570 }
 571
 572 static int ohci_hcd_at91_drv_remove(struct platform_device *pdev)
 573 {
 574         struct at91_usbh_data   *pdata = dev_get_platdata(&pdev->dev);
 575         int                     i;
 576
 577         if (pdata) {
 578                 at91_for_each_port(i) {
 579                         if (!gpio_is_valid(pdata->vbus_pin[i]))
 580                                 continue;
 581                         ohci_at91_usb_set_power(pdata, i, 0);
 582                         gpio_free(pdata->vbus_pin[i]);
 583                 }
 584
 585                 at91_for_each_port(i) {
 586                         if (!gpio_is_valid(pdata->overcurrent_pin[i]))
 587                                 continue;
 588                         free_irq(gpio_to_irq(pdata->overcurrent_pin[i]), pdev);
 589                         gpio_free(pdata->overcurrent_pin[i]);
 590                 }
 591         }
 592
 593         device_init_wakeup(&pdev->dev, 0);
 594         usb_hcd_at91_remove(platform_get_drvdata(pdev), pdev);
 595         return 0;
 596 }
 597
 598 #ifdef CONFIG_PM
 599
 600 static int
 601 ohci_hcd_at91_drv_suspend(struct platform_device *pdev, pm_message_t mesg)
 602 {
 603         struct usb_hcd  *hcd = platform_get_drvdata(pdev);
 604         struct ohci_hcd *ohci = hcd_to_ohci(hcd);
 605         bool            do_wakeup = device_may_wakeup(&pdev->dev);
 606         int             ret;
 607
 608         if (do_wakeup)
 609                 enable_irq_wake(hcd->irq);
 610
 611         ret = ohci_suspend(hcd, do_wakeup);
 612         if (ret) {
 613                 disable_irq_wake(hcd->irq);
 614                 return ret;
 615         }
 616         /*
 617          * The integrated transceivers seem unable to notice disconnect,
 618          * reconnect, or wakeup without the 48 MHz clock active.  so for
 619          * correctness, always discard connection state (using reset).
 620          *
 621          * REVISIT: some boards will be able to turn VBUS off...
 622          */
 623         if (at91_suspend_entering_slow_clock()) {
 624                 ohci->hc_control = ohci_readl(ohci, &ohci->regs->control);
 625                 ohci->hc_control &= OHCI_CTRL_RWC;
 626                 ohci_writel(ohci, ohci->hc_control, &ohci->regs->control);
 627                 ohci->rh_state = OHCI_RH_HALTED;
 628
 629                 /* flush the writes */
 630                 (void) ohci_readl (ohci, &ohci->regs->control);
 631                 at91_stop_clock();
 632         }
 633
 634         return ret;
 635 }
 636
 637 static int ohci_hcd_at91_drv_resume(struct platform_device *pdev)
 638 {
 639         struct usb_hcd  *hcd = platform_get_drvdata(pdev);
 640
 641         if (device_may_wakeup(&pdev->dev))
 642                 disable_irq_wake(hcd->irq);
 643
 644         if (!clocked)
 645                 at91_start_clock();
 646
 647         ohci_resume(hcd, false);
 648         return 0;
 649 }
 650 #else
 651 #define ohci_hcd_at91_drv_suspend NULL
 652 #define ohci_hcd_at91_drv_resume  NULL
 653 #endif
 654
 655 static struct platform_driver ohci_hcd_at91_driver = {
 656         .probe          = ohci_hcd_at91_drv_probe,
 657         .remove         = ohci_hcd_at91_drv_remove,
 658         .shutdown       = usb_hcd_platform_shutdown,
 659         .suspend        = ohci_hcd_at91_drv_suspend,
 660         .resume         = ohci_hcd_at91_drv_resume,
 661         .driver         = {
 662                 .name   = "at91_ohci",
 663                 .owner  = THIS_MODULE,
 664                 .of_match_table = of_match_ptr(at91_ohci_dt_ids),
 665         },
 666 };
 667
 668 static int __init ohci_at91_init(void)
 669 {
 670         if (usb_disabled())
 671                 return -ENODEV;
 672
 673         pr_info("%s: " DRIVER_DESC "\n", hcd_name);
 674         ohci_init_driver(&ohci_at91_hc_driver, NULL);
 675
 676         /*
 677          * The Atmel HW has some unusual quirks, which require Atmel-specific
 678          * workarounds. We override certain hc_driver functions here to
 679          * achieve that. We explicitly do not enhance ohci_driver_overrides to
 680          * allow this more easily, since this is an unusual case, and we don't
 681          * want to encourage others to override these functions by making it
 682          * too easy.
 683          */
 684
 685         ohci_at91_hc_driver.hub_status_data     = ohci_at91_hub_status_data;
 686         ohci_at91_hc_driver.hub_control         = ohci_at91_hub_control;
 687
 688         return platform_driver_register(&ohci_hcd_at91_driver);
 689 }
 690 module_init(ohci_at91_init);
 691
 692 static void __exit ohci_at91_cleanup(void)
 693 {
 694         platform_driver_unregister(&ohci_hcd_at91_driver);
 695 }
 696 module_exit(ohci_at91_cleanup);
 697
 698 MODULE_DESCRIPTION(DRIVER_DESC);
 699 MODULE_LICENSE("GPL");
 700 MODULE_ALIAS("platform:at91_ohci");