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 <mach/hardware.h>
  28 #include <asm/gpio.h>
  29
  30 #include <mach/cpu.h>
  31
  32
  33 #include "ohci.h"
  34
  35 #define valid_port(index)       ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS)
  36 #define at91_for_each_port(index)       \
  37                 for ((index) = 0; (index) < AT91_MAX_USBH_PORTS; (index)++)
  38
  39 /* interface, function and usb clocks; sometimes also an AHB clock */
  40 static struct clk *iclk, *fclk, *uclk, *hclk;
  41 /* interface and function clocks; sometimes also an AHB clock */
  42
  43 #define DRIVER_DESC "OHCI Atmel driver"
  44
  45 static const char hcd_name[] = "ohci-atmel";
  46
  47 static struct hc_driver __read_mostly ohci_at91_hc_driver;
  48 static int clocked;
  49 static int (*orig_ohci_hub_control)(struct usb_hcd  *hcd, u16 typeReq,
  50                         u16 wValue, u16 wIndex, char *buf, u16 wLength);
  51 static int (*orig_ohci_hub_status_data)(struct usb_hcd *hcd, char *buf);
  52
  53 extern int usb_disabled(void);
  54
  55 /*-------------------------------------------------------------------------*/
  56
  57 static void at91_start_clock(void)
  58 {
  59         if (IS_ENABLED(CONFIG_COMMON_CLK)) {
  60                 clk_set_rate(uclk, 48000000);
  61                 clk_prepare_enable(uclk);
  62         }
  63         clk_prepare_enable(hclk);
  64         clk_prepare_enable(iclk);
  65         clk_prepare_enable(fclk);
  66         clocked = 1;
  67 }
  68
  69 static void at91_stop_clock(void)
  70 {
  71         clk_disable_unprepare(fclk);
  72         clk_disable_unprepare(iclk);
  73         clk_disable_unprepare(hclk);
  74         if (IS_ENABLED(CONFIG_COMMON_CLK))
  75                 clk_disable_unprepare(uclk);
  76         clocked = 0;
  77 }
  78
  79 static void at91_start_hc(struct platform_device *pdev)
  80 {
  81         struct usb_hcd *hcd = platform_get_drvdata(pdev);
  82         struct ohci_regs __iomem *regs = hcd->regs;
  83
  84         dev_dbg(&pdev->dev, "start\n");
  85
  86         /*
  87          * Start the USB clocks.
  88          */
  89         at91_start_clock();
  90
  91         /*
  92          * The USB host controller must remain in reset.
  93          */
  94         writel(0, &regs->control);
  95 }
  96
  97 static void at91_stop_hc(struct platform_device *pdev)
  98 {
  99         struct usb_hcd *hcd = platform_get_drvdata(pdev);
 100         struct ohci_regs __iomem *regs = hcd->regs;
 101
 102         dev_dbg(&pdev->dev, "stop\n");
 103
 104         /*
 105          * Put the USB host controller into reset.
 106          */
 107         writel(0, &regs->control);
 108
 109         /*
 110          * Stop the USB clocks.
 111          */
 112         at91_stop_clock();
 113 }
 114
 115
 116 /*-------------------------------------------------------------------------*/
 117
 118 static void usb_hcd_at91_remove (struct usb_hcd *, struct platform_device *);
 119
 120 /* configure so an HC device and id are always provided */
 121 /* always called with process context; sleeping is OK */
 122
 123
 124 /**
 125  * usb_hcd_at91_probe - initialize AT91-based HCDs
 126  * Context: !in_interrupt()
 127  *
 128  * Allocates basic resources for this USB host controller, and
 129  * then invokes the start() method for the HCD associated with it
 130  * through the hotplug entry's driver_data.
 131  */
 132 static int usb_hcd_at91_probe(const struct hc_driver *driver,
 133                         struct platform_device *pdev)
 134 {
 135         struct at91_usbh_data *board;
 136         struct ohci_hcd *ohci;
 137         int retval;
 138         struct usb_hcd *hcd = NULL;
 139         struct device *dev = &pdev->dev;
 140         struct resource *res;
 141         int irq;
 142
 143         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 144         if (!res) {
 145                 dev_dbg(dev, "hcd probe: missing memory resource\n");
 146                 return -ENXIO;
 147         }
 148
 149         irq = platform_get_irq(pdev, 0);
 150         if (irq < 0) {
 151                 dev_dbg(dev, "hcd probe: missing irq resource\n");
 152                 return irq;
 153         }
 154
 155         hcd = usb_create_hcd(driver, dev, "at91");
 156         if (!hcd)
 157                 return -ENOMEM;
 158         hcd->rsrc_start = res->start;
 159         hcd->rsrc_len = resource_size(res);
 160
 161         hcd->regs = devm_ioremap_resource(dev, res);
 162         if (IS_ERR(hcd->regs)) {
 163                 retval = PTR_ERR(hcd->regs);
 164                 goto err;
 165         }
 166
 167         iclk = devm_clk_get(dev, "ohci_clk");
 168         if (IS_ERR(iclk)) {
 169                 dev_err(dev, "failed to get ohci_clk\n");
 170                 retval = PTR_ERR(iclk);
 171                 goto err;
 172         }
 173         fclk = devm_clk_get(dev, "uhpck");
 174         if (IS_ERR(fclk)) {
 175                 dev_err(dev, "failed to get uhpck\n");
 176                 retval = PTR_ERR(fclk);
 177                 goto err;
 178         }
 179         hclk = devm_clk_get(dev, "hclk");
 180         if (IS_ERR(hclk)) {
 181                 dev_err(dev, "failed to get hclk\n");
 182                 retval = PTR_ERR(hclk);
 183                 goto err;
 184         }
 185         if (IS_ENABLED(CONFIG_COMMON_CLK)) {
 186                 uclk = devm_clk_get(dev, "usb_clk");
 187                 if (IS_ERR(uclk)) {
 188                         dev_err(dev, "failed to get uclk\n");
 189                         retval = PTR_ERR(uclk);
 190                         goto err;
 191                 }
 192         }
 193
 194         board = hcd->self.controller->platform_data;
 195         ohci = hcd_to_ohci(hcd);
 196         ohci->num_ports = board->ports;
 197         at91_start_hc(pdev);
 198
 199         retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
 200         if (retval == 0) {
 201                 device_wakeup_enable(hcd->self.controller);
 202                 return retval;
 203         }
 204
 205         /* Error handling */
 206         at91_stop_hc(pdev);
 207
 208  err:
 209         usb_put_hcd(hcd);
 210         return retval;
 211 }
 212
 213
 214 /* may be called with controller, bus, and devices active */
 215
 216 /**
 217  * usb_hcd_at91_remove - shutdown processing for AT91-based HCDs
 218  * @dev: USB Host Controller being removed
 219  * Context: !in_interrupt()
 220  *
 221  * Reverses the effect of usb_hcd_at91_probe(), first invoking
 222  * the HCD's stop() method.  It is always called from a thread
 223  * context, "rmmod" or something similar.
 224  *
 225  */
 226 static void usb_hcd_at91_remove(struct usb_hcd *hcd,
 227                                 struct platform_device *pdev)
 228 {
 229         usb_remove_hcd(hcd);
 230         at91_stop_hc(pdev);
 231         usb_put_hcd(hcd);
 232 }
 233
 234 /*-------------------------------------------------------------------------*/
 235 static void ohci_at91_usb_set_power(struct at91_usbh_data *pdata, int port, int enable)
 236 {
 237         if (!valid_port(port))
 238                 return;
 239
 240         if (!gpio_is_valid(pdata->vbus_pin[port]))
 241                 return;
 242
 243         gpio_set_value(pdata->vbus_pin[port],
 244                        pdata->vbus_pin_active_low[port] ^ enable);
 245 }
 246
 247 static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
 248 {
 249         if (!valid_port(port))
 250                 return -EINVAL;
 251
 252         if (!gpio_is_valid(pdata->vbus_pin[port]))
 253                 return -EINVAL;
 254
 255         return gpio_get_value(pdata->vbus_pin[port]) ^
 256                 pdata->vbus_pin_active_low[port];
 257 }
 258
 259 /*
 260  * Update the status data from the hub with the over-current indicator change.
 261  */
 262 static int ohci_at91_hub_status_data(struct usb_hcd *hcd, char *buf)
 263 {
 264         struct at91_usbh_data *pdata = hcd->self.controller->platform_data;
 265         int length = orig_ohci_hub_status_data(hcd, buf);
 266         int port;
 267
 268         at91_for_each_port(port) {
 269                 if (pdata->overcurrent_changed[port]) {
 270                         if (!length)
 271                                 length = 1;
 272                         buf[0] |= 1 << (port + 1);
 273                 }
 274         }
 275
 276         return length;
 277 }
 278
 279 /*
 280  * Look at the control requests to the root hub and see if we need to override.
 281  */
 282 static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 283                                  u16 wIndex, char *buf, u16 wLength)
 284 {
 285         struct at91_usbh_data *pdata = dev_get_platdata(hcd->self.controller);
 286         struct usb_hub_descriptor *desc;
 287         int ret = -EINVAL;
 288         u32 *data = (u32 *)buf;
 289
 290         dev_dbg(hcd->self.controller,
 291                 "ohci_at91_hub_control(%p,0x%04x,0x%04x,0x%04x,%p,%04x)\n",
 292                 hcd, typeReq, wValue, wIndex, buf, wLength);
 293
 294         wIndex--;
 295
 296         switch (typeReq) {
 297         case SetPortFeature:
 298                 if (wValue == USB_PORT_FEAT_POWER) {
 299                         dev_dbg(hcd->self.controller, "SetPortFeat: POWER\n");
 300                         if (valid_port(wIndex)) {
 301                                 ohci_at91_usb_set_power(pdata, wIndex, 1);
 302                                 ret = 0;
 303                         }
 304
 305                         goto out;
 306                 }
 307                 break;
 308
 309         case ClearPortFeature:
 310                 switch (wValue) {
 311                 case USB_PORT_FEAT_C_OVER_CURRENT:
 312                         dev_dbg(hcd->self.controller,
 313                                 "ClearPortFeature: C_OVER_CURRENT\n");
 314
 315                         if (valid_port(wIndex)) {
 316                                 pdata->overcurrent_changed[wIndex] = 0;
 317                                 pdata->overcurrent_status[wIndex] = 0;
 318                         }
 319
 320                         goto out;
 321
 322                 case USB_PORT_FEAT_OVER_CURRENT:
 323                         dev_dbg(hcd->self.controller,
 324                                 "ClearPortFeature: OVER_CURRENT\n");
 325
 326                         if (valid_port(wIndex))
 327                                 pdata->overcurrent_status[wIndex] = 0;
 328
 329                         goto out;
 330
 331                 case USB_PORT_FEAT_POWER:
 332                         dev_dbg(hcd->self.controller,
 333                                 "ClearPortFeature: POWER\n");
 334
 335                         if (valid_port(wIndex)) {
 336                                 ohci_at91_usb_set_power(pdata, wIndex, 0);
 337                                 return 0;
 338                         }
 339                 }
 340                 break;
 341         }
 342
 343         ret = orig_ohci_hub_control(hcd, typeReq, wValue, wIndex + 1,
 344                                 buf, wLength);
 345         if (ret)
 346                 goto out;
 347
 348         switch (typeReq) {
 349         case GetHubDescriptor:
 350
 351                 /* update the hub's descriptor */
 352
 353                 desc = (struct usb_hub_descriptor *)buf;
 354
 355                 dev_dbg(hcd->self.controller, "wHubCharacteristics 0x%04x\n",
 356                         desc->wHubCharacteristics);
 357
 358                 /* remove the old configurations for power-switching, and
 359                  * over-current protection, and insert our new configuration
 360                  */
 361
 362                 desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_LPSM);
 363                 desc->wHubCharacteristics |= cpu_to_le16(0x0001);
 364
 365                 if (pdata->overcurrent_supported) {
 366                         desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_OCPM);
 367                         desc->wHubCharacteristics |=  cpu_to_le16(0x0008|0x0001);
 368                 }
 369
 370                 dev_dbg(hcd->self.controller, "wHubCharacteristics after 0x%04x\n",
 371                         desc->wHubCharacteristics);
 372
 373                 return ret;
 374
 375         case GetPortStatus:
 376                 /* check port status */
 377
 378                 dev_dbg(hcd->self.controller, "GetPortStatus(%d)\n", wIndex);
 379
 380                 if (valid_port(wIndex)) {
 381                         if (!ohci_at91_usb_get_power(pdata, wIndex))
 382                                 *data &= ~cpu_to_le32(RH_PS_PPS);
 383
 384                         if (pdata->overcurrent_changed[wIndex])
 385                                 *data |= cpu_to_le32(RH_PS_OCIC);
 386
 387                         if (pdata->overcurrent_status[wIndex])
 388                                 *data |= cpu_to_le32(RH_PS_POCI);
 389                 }
 390         }
 391
 392  out:
 393         return ret;
 394 }
 395
 396 /*-------------------------------------------------------------------------*/
 397
 398 static irqreturn_t ohci_hcd_at91_overcurrent_irq(int irq, void *data)
 399 {
 400         struct platform_device *pdev = data;
 401         struct at91_usbh_data *pdata = dev_get_platdata(&pdev->dev);
 402         int val, gpio, port;
 403
 404         /* From the GPIO notifying the over-current situation, find
 405          * out the corresponding port */
 406         at91_for_each_port(port) {
 407                 if (gpio_is_valid(pdata->overcurrent_pin[port]) &&
 408                                 gpio_to_irq(pdata->overcurrent_pin[port]) == irq) {
 409                         gpio = pdata->overcurrent_pin[port];
 410                         break;
 411                 }
 412         }
 413
 414         if (port == AT91_MAX_USBH_PORTS) {
 415                 dev_err(& pdev->dev, "overcurrent interrupt from unknown GPIO\n");
 416                 return IRQ_HANDLED;
 417         }
 418
 419         val = gpio_get_value(gpio);
 420
 421         /* When notified of an over-current situation, disable power
 422            on the corresponding port, and mark this port in
 423            over-current. */
 424         if (!val) {
 425                 ohci_at91_usb_set_power(pdata, port, 0);
 426                 pdata->overcurrent_status[port]  = 1;
 427                 pdata->overcurrent_changed[port] = 1;
 428         }
 429
 430         dev_dbg(& pdev->dev, "overcurrent situation %s\n",
 431                 val ? "exited" : "notified");
 432
 433         return IRQ_HANDLED;
 434 }
 435
 436 #ifdef CONFIG_OF
 437 static const struct of_device_id at91_ohci_dt_ids[] = {
 438         { .compatible = "atmel,at91rm9200-ohci" },
 439         { /* sentinel */ }
 440 };
 441
 442 MODULE_DEVICE_TABLE(of, at91_ohci_dt_ids);
 443
 444 static int ohci_at91_of_init(struct platform_device *pdev)
 445 {
 446         struct device_node *np = pdev->dev.of_node;
 447         int i, gpio, ret;
 448         enum of_gpio_flags flags;
 449         struct at91_usbh_data   *pdata;
 450         u32 ports;
 451
 452         if (!np)
 453                 return 0;
 454
 455         /* Right now device-tree probed devices don't get dma_mask set.
 456          * Since shared usb code relies on it, set it here for now.
 457          * Once we have dma capability bindings this can go away.
 458          */
 459         ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 460         if (ret)
 461                 return ret;
 462
 463         pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 464         if (!pdata)
 465                 return -ENOMEM;
 466
 467         if (!of_property_read_u32(np, "num-ports", &ports))
 468                 pdata->ports = ports;
 469
 470         at91_for_each_port(i) {
 471                 gpio = of_get_named_gpio_flags(np, "atmel,vbus-gpio", i, &flags);
 472                 pdata->vbus_pin[i] = gpio;
 473                 if (!gpio_is_valid(gpio))
 474                         continue;
 475                 pdata->vbus_pin_active_low[i] = flags & OF_GPIO_ACTIVE_LOW;
 476         }
 477
 478         at91_for_each_port(i)
 479                 pdata->overcurrent_pin[i] =
 480                         of_get_named_gpio_flags(np, "atmel,oc-gpio", i, &flags);
 481
 482         pdev->dev.platform_data = pdata;
 483
 484         return 0;
 485 }
 486 #else
 487 static int ohci_at91_of_init(struct platform_device *pdev)
 488 {
 489         return 0;
 490 }
 491 #endif
 492
 493 /*-------------------------------------------------------------------------*/
 494
 495 static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
 496 {
 497         struct at91_usbh_data   *pdata;
 498         int                     i;
 499         int                     gpio;
 500         int                     ret;
 501
 502         ret = ohci_at91_of_init(pdev);
 503         if (ret)
 504                 return ret;
 505
 506         pdata = dev_get_platdata(&pdev->dev);
 507
 508         if (pdata) {
 509                 at91_for_each_port(i) {
 510                         /*
 511                          * do not configure PIO if not in relation with
 512                          * real USB port on board
 513                          */
 514                         if (i >= pdata->ports) {
 515                                 pdata->vbus_pin[i] = -EINVAL;
 516                                 pdata->overcurrent_pin[i] = -EINVAL;
 517                                 break;
 518                         }
 519
 520                         if (!gpio_is_valid(pdata->vbus_pin[i]))
 521                                 continue;
 522                         gpio = pdata->vbus_pin[i];
 523
 524                         ret = gpio_request(gpio, "ohci_vbus");
 525                         if (ret) {
 526                                 dev_err(&pdev->dev,
 527                                         "can't request vbus gpio %d\n", gpio);
 528                                 continue;
 529                         }
 530                         ret = gpio_direction_output(gpio,
 531                                                 !pdata->vbus_pin_active_low[i]);
 532                         if (ret) {
 533                                 dev_err(&pdev->dev,
 534                                         "can't put vbus gpio %d as output %d\n",
 535                                         gpio, !pdata->vbus_pin_active_low[i]);
 536                                 gpio_free(gpio);
 537                                 continue;
 538                         }
 539
 540                         ohci_at91_usb_set_power(pdata, i, 1);
 541                 }
 542
 543                 at91_for_each_port(i) {
 544                         if (!gpio_is_valid(pdata->overcurrent_pin[i]))
 545                                 continue;
 546                         gpio = pdata->overcurrent_pin[i];
 547
 548                         ret = gpio_request(gpio, "ohci_overcurrent");
 549                         if (ret) {
 550                                 dev_err(&pdev->dev,
 551                                         "can't request overcurrent gpio %d\n",
 552                                         gpio);
 553                                 continue;
 554                         }
 555
 556                         ret = gpio_direction_input(gpio);
 557                         if (ret) {
 558                                 dev_err(&pdev->dev,
 559                                         "can't configure overcurrent gpio %d as input\n",
 560                                         gpio);
 561                                 gpio_free(gpio);
 562                                 continue;
 563                         }
 564
 565                         ret = request_irq(gpio_to_irq(gpio),
 566                                           ohci_hcd_at91_overcurrent_irq,
 567                                           IRQF_SHARED, "ohci_overcurrent", pdev);
 568                         if (ret) {
 569                                 gpio_free(gpio);
 570                                 dev_err(&pdev->dev,
 571                                         "can't get gpio IRQ for overcurrent\n");
 572                         }
 573                 }
 574         }
 575
 576         device_init_wakeup(&pdev->dev, 1);
 577         return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
 578 }
 579
 580 static int ohci_hcd_at91_drv_remove(struct platform_device *pdev)
 581 {
 582         struct at91_usbh_data   *pdata = dev_get_platdata(&pdev->dev);
 583         int                     i;
 584
 585         if (pdata) {
 586                 at91_for_each_port(i) {
 587                         if (!gpio_is_valid(pdata->vbus_pin[i]))
 588                                 continue;
 589                         ohci_at91_usb_set_power(pdata, i, 0);
 590                         gpio_free(pdata->vbus_pin[i]);
 591                 }
 592
 593                 at91_for_each_port(i) {
 594                         if (!gpio_is_valid(pdata->overcurrent_pin[i]))
 595                                 continue;
 596                         free_irq(gpio_to_irq(pdata->overcurrent_pin[i]), pdev);
 597                         gpio_free(pdata->overcurrent_pin[i]);
 598                 }
 599         }
 600
 601         device_init_wakeup(&pdev->dev, 0);
 602         usb_hcd_at91_remove(platform_get_drvdata(pdev), pdev);
 603         return 0;
 604 }
 605
 606 #ifdef CONFIG_PM
 607
 608 static int
 609 ohci_hcd_at91_drv_suspend(struct platform_device *pdev, pm_message_t mesg)
 610 {
 611         struct usb_hcd  *hcd = platform_get_drvdata(pdev);
 612         struct ohci_hcd *ohci = hcd_to_ohci(hcd);
 613         bool            do_wakeup = device_may_wakeup(&pdev->dev);
 614         int             ret;
 615
 616         if (do_wakeup)
 617                 enable_irq_wake(hcd->irq);
 618
 619         ret = ohci_suspend(hcd, do_wakeup);
 620         if (ret) {
 621                 disable_irq_wake(hcd->irq);
 622                 return ret;
 623         }
 624         /*
 625          * The integrated transceivers seem unable to notice disconnect,
 626          * reconnect, or wakeup without the 48 MHz clock active.  so for
 627          * correctness, always discard connection state (using reset).
 628          *
 629          * REVISIT: some boards will be able to turn VBUS off...
 630          */
 631         if (at91_suspend_entering_slow_clock()) {
 632                 ohci->hc_control = ohci_readl(ohci, &ohci->regs->control);
 633                 ohci->hc_control &= OHCI_CTRL_RWC;
 634                 ohci_writel(ohci, ohci->hc_control, &ohci->regs->control);
 635                 ohci->rh_state = OHCI_RH_HALTED;
 636
 637                 /* flush the writes */
 638                 (void) ohci_readl (ohci, &ohci->regs->control);
 639                 at91_stop_clock();
 640         }
 641
 642         return ret;
 643 }
 644
 645 static int ohci_hcd_at91_drv_resume(struct platform_device *pdev)
 646 {
 647         struct usb_hcd  *hcd = platform_get_drvdata(pdev);
 648
 649         if (device_may_wakeup(&pdev->dev))
 650                 disable_irq_wake(hcd->irq);
 651
 652         if (!clocked)
 653                 at91_start_clock();
 654
 655         ohci_resume(hcd, false);
 656         return 0;
 657 }
 658 #else
 659 #define ohci_hcd_at91_drv_suspend NULL
 660 #define ohci_hcd_at91_drv_resume  NULL
 661 #endif
 662
 663 static struct platform_driver ohci_hcd_at91_driver = {
 664         .probe          = ohci_hcd_at91_drv_probe,
 665         .remove         = ohci_hcd_at91_drv_remove,
 666         .shutdown       = usb_hcd_platform_shutdown,
 667         .suspend        = ohci_hcd_at91_drv_suspend,
 668         .resume         = ohci_hcd_at91_drv_resume,
 669         .driver         = {
 670                 .name   = "at91_ohci",
 671                 .owner  = THIS_MODULE,
 672                 .of_match_table = of_match_ptr(at91_ohci_dt_ids),
 673         },
 674 };
 675
 676 static int __init ohci_at91_init(void)
 677 {
 678         if (usb_disabled())
 679                 return -ENODEV;
 680
 681         pr_info("%s: " DRIVER_DESC "\n", hcd_name);
 682         ohci_init_driver(&ohci_at91_hc_driver, NULL);
 683
 684         /*
 685          * The Atmel HW has some unusual quirks, which require Atmel-specific
 686          * workarounds. We override certain hc_driver functions here to
 687          * achieve that. We explicitly do not enhance ohci_driver_overrides to
 688          * allow this more easily, since this is an unusual case, and we don't
 689          * want to encourage others to override these functions by making it
 690          * too easy.
 691          */
 692
 693         orig_ohci_hub_control = ohci_at91_hc_driver.hub_control;
 694         orig_ohci_hub_status_data = ohci_at91_hc_driver.hub_status_data;
 695
 696         ohci_at91_hc_driver.hub_status_data     = ohci_at91_hub_status_data;
 697         ohci_at91_hc_driver.hub_control         = ohci_at91_hub_control;
 698
 699         return platform_driver_register(&ohci_hcd_at91_driver);
 700 }
 701 module_init(ohci_at91_init);
 702
 703 static void __exit ohci_at91_cleanup(void)
 704 {
 705         platform_driver_unregister(&ohci_hcd_at91_driver);
 706 }
 707 module_exit(ohci_at91_cleanup);
 708
 709 MODULE_DESCRIPTION(DRIVER_DESC);
 710 MODULE_LICENSE("GPL");
 711 MODULE_ALIAS("platform:at91_ohci");