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 #define hcd_to_ohci_at91_priv(h) \
  37         ((struct ohci_at91_priv *)hcd_to_ohci(h)->priv)
  38
  39 #define AT91_MAX_USBH_PORTS     3
  40 struct at91_usbh_data {
  41         int vbus_pin[AT91_MAX_USBH_PORTS];      /* port power-control pin */
  42         int overcurrent_pin[AT91_MAX_USBH_PORTS];
  43         u8 ports;                               /* number of ports on root hub */
  44         u8 overcurrent_supported;
  45         u8 vbus_pin_active_low[AT91_MAX_USBH_PORTS];
  46         u8 overcurrent_status[AT91_MAX_USBH_PORTS];
  47         u8 overcurrent_changed[AT91_MAX_USBH_PORTS];
  48 };
  49
  50 struct ohci_at91_priv {
  51         struct clk *iclk;
  52         struct clk *fclk;
  53         struct clk *hclk;
  54         bool clocked;
  55         bool wakeup;            /* Saved wake-up state for resume */
  56 };
  57 /* interface and function clocks; sometimes also an AHB clock */
  58
  59 #define DRIVER_DESC "OHCI Atmel driver"
  60
  61 static const char hcd_name[] = "ohci-atmel";
  62
  63 static struct hc_driver __read_mostly ohci_at91_hc_driver;
  64
  65 static const struct ohci_driver_overrides ohci_at91_drv_overrides __initconst = {
  66         .extra_priv_size = sizeof(struct ohci_at91_priv),
  67 };
  68
  69 extern int usb_disabled(void);
  70
  71 /*-------------------------------------------------------------------------*/
  72
  73 static void at91_start_clock(struct ohci_at91_priv *ohci_at91)
  74 {
  75         if (ohci_at91->clocked)
  76                 return;
  77
  78         clk_set_rate(ohci_at91->fclk, 48000000);
  79         clk_prepare_enable(ohci_at91->hclk);
  80         clk_prepare_enable(ohci_at91->iclk);
  81         clk_prepare_enable(ohci_at91->fclk);
  82         ohci_at91->clocked = true;
  83 }
  84
  85 static void at91_stop_clock(struct ohci_at91_priv *ohci_at91)
  86 {
  87         if (!ohci_at91->clocked)
  88                 return;
  89
  90         clk_disable_unprepare(ohci_at91->fclk);
  91         clk_disable_unprepare(ohci_at91->iclk);
  92         clk_disable_unprepare(ohci_at91->hclk);
  93         ohci_at91->clocked = false;
  94 }
  95
  96 static void at91_start_hc(struct platform_device *pdev)
  97 {
  98         struct usb_hcd *hcd = platform_get_drvdata(pdev);
  99         struct ohci_regs __iomem *regs = hcd->regs;
 100         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 101
 102         dev_dbg(&pdev->dev, "start\n");
 103
 104         /*
 105          * Start the USB clocks.
 106          */
 107         at91_start_clock(ohci_at91);
 108
 109         /*
 110          * The USB host controller must remain in reset.
 111          */
 112         writel(0, &regs->control);
 113 }
 114
 115 static void at91_stop_hc(struct platform_device *pdev)
 116 {
 117         struct usb_hcd *hcd = platform_get_drvdata(pdev);
 118         struct ohci_regs __iomem *regs = hcd->regs;
 119         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 120
 121         dev_dbg(&pdev->dev, "stop\n");
 122
 123         /*
 124          * Put the USB host controller into reset.
 125          */
 126         writel(0, &regs->control);
 127
 128         /*
 129          * Stop the USB clocks.
 130          */
 131         at91_stop_clock(ohci_at91);
 132 }
 133
 134
 135 /*-------------------------------------------------------------------------*/
 136
 137 static void usb_hcd_at91_remove (struct usb_hcd *, struct platform_device *);
 138
 139 /* configure so an HC device and id are always provided */
 140 /* always called with process context; sleeping is OK */
 141
 142
 143 /**
 144  * usb_hcd_at91_probe - initialize AT91-based HCDs
 145  * Context: !in_interrupt()
 146  *
 147  * Allocates basic resources for this USB host controller, and
 148  * then invokes the start() method for the HCD associated with it
 149  * through the hotplug entry's driver_data.
 150  */
 151 static int usb_hcd_at91_probe(const struct hc_driver *driver,
 152                         struct platform_device *pdev)
 153 {
 154         struct at91_usbh_data *board;
 155         struct ohci_hcd *ohci;
 156         int retval;
 157         struct usb_hcd *hcd;
 158         struct ohci_at91_priv *ohci_at91;
 159         struct device *dev = &pdev->dev;
 160         struct resource *res;
 161         int irq;
 162
 163         irq = platform_get_irq(pdev, 0);
 164         if (irq < 0) {
 165                 dev_dbg(dev, "hcd probe: missing irq resource\n");
 166                 return irq;
 167         }
 168
 169         hcd = usb_create_hcd(driver, dev, "at91");
 170         if (!hcd)
 171                 return -ENOMEM;
 172         ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 173
 174         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 175         hcd->regs = devm_ioremap_resource(dev, res);
 176         if (IS_ERR(hcd->regs)) {
 177                 retval = PTR_ERR(hcd->regs);
 178                 goto err;
 179         }
 180         hcd->rsrc_start = res->start;
 181         hcd->rsrc_len = resource_size(res);
 182
 183         ohci_at91->iclk = devm_clk_get(dev, "ohci_clk");
 184         if (IS_ERR(ohci_at91->iclk)) {
 185                 dev_err(dev, "failed to get ohci_clk\n");
 186                 retval = PTR_ERR(ohci_at91->iclk);
 187                 goto err;
 188         }
 189         ohci_at91->fclk = devm_clk_get(dev, "uhpck");
 190         if (IS_ERR(ohci_at91->fclk)) {
 191                 dev_err(dev, "failed to get uhpck\n");
 192                 retval = PTR_ERR(ohci_at91->fclk);
 193                 goto err;
 194         }
 195         ohci_at91->hclk = devm_clk_get(dev, "hclk");
 196         if (IS_ERR(ohci_at91->hclk)) {
 197                 dev_err(dev, "failed to get hclk\n");
 198                 retval = PTR_ERR(ohci_at91->hclk);
 199                 goto err;
 200         }
 201
 202         board = hcd->self.controller->platform_data;
 203         ohci = hcd_to_ohci(hcd);
 204         ohci->num_ports = board->ports;
 205         at91_start_hc(pdev);
 206
 207         retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
 208         if (retval == 0) {
 209                 device_wakeup_enable(hcd->self.controller);
 210                 return retval;
 211         }
 212
 213         /* Error handling */
 214         at91_stop_hc(pdev);
 215
 216  err:
 217         usb_put_hcd(hcd);
 218         return retval;
 219 }
 220
 221
 222 /* may be called with controller, bus, and devices active */
 223
 224 /**
 225  * usb_hcd_at91_remove - shutdown processing for AT91-based HCDs
 226  * @dev: USB Host Controller being removed
 227  * Context: !in_interrupt()
 228  *
 229  * Reverses the effect of usb_hcd_at91_probe(), first invoking
 230  * the HCD's stop() method.  It is always called from a thread
 231  * context, "rmmod" or something similar.
 232  *
 233  */
 234 static void usb_hcd_at91_remove(struct usb_hcd *hcd,
 235                                 struct platform_device *pdev)
 236 {
 237         usb_remove_hcd(hcd);
 238         at91_stop_hc(pdev);
 239         usb_put_hcd(hcd);
 240 }
 241
 242 /*-------------------------------------------------------------------------*/
 243 static void ohci_at91_usb_set_power(struct at91_usbh_data *pdata, int port, int enable)
 244 {
 245         if (!valid_port(port))
 246                 return;
 247
 248         if (!gpio_is_valid(pdata->vbus_pin[port]))
 249                 return;
 250
 251         gpio_set_value(pdata->vbus_pin[port],
 252                        pdata->vbus_pin_active_low[port] ^ enable);
 253 }
 254
 255 static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
 256 {
 257         if (!valid_port(port))
 258                 return -EINVAL;
 259
 260         if (!gpio_is_valid(pdata->vbus_pin[port]))
 261                 return -EINVAL;
 262
 263         return gpio_get_value(pdata->vbus_pin[port]) ^
 264                 pdata->vbus_pin_active_low[port];
 265 }
 266
 267 /*
 268  * Update the status data from the hub with the over-current indicator change.
 269  */
 270 static int ohci_at91_hub_status_data(struct usb_hcd *hcd, char *buf)
 271 {
 272         struct at91_usbh_data *pdata = hcd->self.controller->platform_data;
 273         int length = ohci_hub_status_data(hcd, buf);
 274         int port;
 275
 276         at91_for_each_port(port) {
 277                 if (pdata->overcurrent_changed[port]) {
 278                         if (!length)
 279                                 length = 1;
 280                         buf[0] |= 1 << (port + 1);
 281                 }
 282         }
 283
 284         return length;
 285 }
 286
 287 /*
 288  * Look at the control requests to the root hub and see if we need to override.
 289  */
 290 static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 291                                  u16 wIndex, char *buf, u16 wLength)
 292 {
 293         struct at91_usbh_data *pdata = dev_get_platdata(hcd->self.controller);
 294         struct usb_hub_descriptor *desc;
 295         int ret = -EINVAL;
 296         u32 *data = (u32 *)buf;
 297
 298         dev_dbg(hcd->self.controller,
 299                 "ohci_at91_hub_control(%p,0x%04x,0x%04x,0x%04x,%p,%04x)\n",
 300                 hcd, typeReq, wValue, wIndex, buf, wLength);
 301
 302         wIndex--;
 303
 304         switch (typeReq) {
 305         case SetPortFeature:
 306                 if (wValue == USB_PORT_FEAT_POWER) {
 307                         dev_dbg(hcd->self.controller, "SetPortFeat: POWER\n");
 308                         if (valid_port(wIndex)) {
 309                                 ohci_at91_usb_set_power(pdata, wIndex, 1);
 310                                 ret = 0;
 311                         }
 312
 313                         goto out;
 314                 }
 315                 break;
 316
 317         case ClearPortFeature:
 318                 switch (wValue) {
 319                 case USB_PORT_FEAT_C_OVER_CURRENT:
 320                         dev_dbg(hcd->self.controller,
 321                                 "ClearPortFeature: C_OVER_CURRENT\n");
 322
 323                         if (valid_port(wIndex)) {
 324                                 pdata->overcurrent_changed[wIndex] = 0;
 325                                 pdata->overcurrent_status[wIndex] = 0;
 326                         }
 327
 328                         goto out;
 329
 330                 case USB_PORT_FEAT_OVER_CURRENT:
 331                         dev_dbg(hcd->self.controller,
 332                                 "ClearPortFeature: OVER_CURRENT\n");
 333
 334                         if (valid_port(wIndex))
 335                                 pdata->overcurrent_status[wIndex] = 0;
 336
 337                         goto out;
 338
 339                 case USB_PORT_FEAT_POWER:
 340                         dev_dbg(hcd->self.controller,
 341                                 "ClearPortFeature: POWER\n");
 342
 343                         if (valid_port(wIndex)) {
 344                                 ohci_at91_usb_set_power(pdata, wIndex, 0);
 345                                 return 0;
 346                         }
 347                 }
 348                 break;
 349         }
 350
 351         ret = ohci_hub_control(hcd, typeReq, wValue, wIndex + 1, buf, wLength);
 352         if (ret)
 353                 goto out;
 354
 355         switch (typeReq) {
 356         case GetHubDescriptor:
 357
 358                 /* update the hub's descriptor */
 359
 360                 desc = (struct usb_hub_descriptor *)buf;
 361
 362                 dev_dbg(hcd->self.controller, "wHubCharacteristics 0x%04x\n",
 363                         desc->wHubCharacteristics);
 364
 365                 /* remove the old configurations for power-switching, and
 366                  * over-current protection, and insert our new configuration
 367                  */
 368
 369                 desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_LPSM);
 370                 desc->wHubCharacteristics |=
 371                         cpu_to_le16(HUB_CHAR_INDV_PORT_LPSM);
 372
 373                 if (pdata->overcurrent_supported) {
 374                         desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_OCPM);
 375                         desc->wHubCharacteristics |=
 376                                 cpu_to_le16(HUB_CHAR_INDV_PORT_OCPM);
 377                 }
 378
 379                 dev_dbg(hcd->self.controller, "wHubCharacteristics after 0x%04x\n",
 380                         desc->wHubCharacteristics);
 381
 382                 return ret;
 383
 384         case GetPortStatus:
 385                 /* check port status */
 386
 387                 dev_dbg(hcd->self.controller, "GetPortStatus(%d)\n", wIndex);
 388
 389                 if (valid_port(wIndex)) {
 390                         if (!ohci_at91_usb_get_power(pdata, wIndex))
 391                                 *data &= ~cpu_to_le32(RH_PS_PPS);
 392
 393                         if (pdata->overcurrent_changed[wIndex])
 394                                 *data |= cpu_to_le32(RH_PS_OCIC);
 395
 396                         if (pdata->overcurrent_status[wIndex])
 397                                 *data |= cpu_to_le32(RH_PS_POCI);
 398                 }
 399         }
 400
 401  out:
 402         return ret;
 403 }
 404
 405 /*-------------------------------------------------------------------------*/
 406
 407 static irqreturn_t ohci_hcd_at91_overcurrent_irq(int irq, void *data)
 408 {
 409         struct platform_device *pdev = data;
 410         struct at91_usbh_data *pdata = dev_get_platdata(&pdev->dev);
 411         int val, gpio, port;
 412
 413         /* From the GPIO notifying the over-current situation, find
 414          * out the corresponding port */
 415         at91_for_each_port(port) {
 416                 if (gpio_is_valid(pdata->overcurrent_pin[port]) &&
 417                                 gpio_to_irq(pdata->overcurrent_pin[port]) == irq) {
 418                         gpio = pdata->overcurrent_pin[port];
 419                         break;
 420                 }
 421         }
 422
 423         if (port == AT91_MAX_USBH_PORTS) {
 424                 dev_err(& pdev->dev, "overcurrent interrupt from unknown GPIO\n");
 425                 return IRQ_HANDLED;
 426         }
 427
 428         val = gpio_get_value(gpio);
 429
 430         /* When notified of an over-current situation, disable power
 431            on the corresponding port, and mark this port in
 432            over-current. */
 433         if (!val) {
 434                 ohci_at91_usb_set_power(pdata, port, 0);
 435                 pdata->overcurrent_status[port]  = 1;
 436                 pdata->overcurrent_changed[port] = 1;
 437         }
 438
 439         dev_dbg(& pdev->dev, "overcurrent situation %s\n",
 440                 val ? "exited" : "notified");
 441
 442         return IRQ_HANDLED;
 443 }
 444
 445 #ifdef CONFIG_OF
 446 static const struct of_device_id at91_ohci_dt_ids[] = {
 447         { .compatible = "atmel,at91rm9200-ohci" },
 448         { /* sentinel */ }
 449 };
 450
 451 MODULE_DEVICE_TABLE(of, at91_ohci_dt_ids);
 452
 453 static int ohci_at91_of_init(struct platform_device *pdev)
 454 {
 455         struct device_node *np = pdev->dev.of_node;
 456         int i, gpio, ret;
 457         enum of_gpio_flags flags;
 458         struct at91_usbh_data   *pdata;
 459         u32 ports;
 460
 461         if (!np)
 462                 return 0;
 463
 464         /* Right now device-tree probed devices don't get dma_mask set.
 465          * Since shared usb code relies on it, set it here for now.
 466          * Once we have dma capability bindings this can go away.
 467          */
 468         ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 469         if (ret)
 470                 return ret;
 471
 472         pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 473         if (!pdata)
 474                 return -ENOMEM;
 475
 476         if (!of_property_read_u32(np, "num-ports", &ports))
 477                 pdata->ports = ports;
 478
 479         at91_for_each_port(i) {
 480                 gpio = of_get_named_gpio_flags(np, "atmel,vbus-gpio", i, &flags);
 481                 pdata->vbus_pin[i] = gpio;
 482                 if (!gpio_is_valid(gpio))
 483                         continue;
 484                 pdata->vbus_pin_active_low[i] = flags & OF_GPIO_ACTIVE_LOW;
 485         }
 486
 487         at91_for_each_port(i)
 488                 pdata->overcurrent_pin[i] =
 489                         of_get_named_gpio_flags(np, "atmel,oc-gpio", i, &flags);
 490
 491         pdev->dev.platform_data = pdata;
 492
 493         return 0;
 494 }
 495 #else
 496 static int ohci_at91_of_init(struct platform_device *pdev)
 497 {
 498         return 0;
 499 }
 500 #endif
 501
 502 /*-------------------------------------------------------------------------*/
 503
 504 static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
 505 {
 506         struct at91_usbh_data   *pdata;
 507         int                     i;
 508         int                     gpio;
 509         int                     ret;
 510
 511         ret = ohci_at91_of_init(pdev);
 512         if (ret)
 513                 return ret;
 514
 515         pdata = dev_get_platdata(&pdev->dev);
 516
 517         if (pdata) {
 518                 at91_for_each_port(i) {
 519                         /*
 520                          * do not configure PIO if not in relation with
 521                          * real USB port on board
 522                          */
 523                         if (i >= pdata->ports) {
 524                                 pdata->vbus_pin[i] = -EINVAL;
 525                                 pdata->overcurrent_pin[i] = -EINVAL;
 526                                 break;
 527                         }
 528
 529                         if (!gpio_is_valid(pdata->vbus_pin[i]))
 530                                 continue;
 531                         gpio = pdata->vbus_pin[i];
 532
 533                         ret = gpio_request(gpio, "ohci_vbus");
 534                         if (ret) {
 535                                 dev_err(&pdev->dev,
 536                                         "can't request vbus gpio %d\n", gpio);
 537                                 continue;
 538                         }
 539                         ret = gpio_direction_output(gpio,
 540                                                 !pdata->vbus_pin_active_low[i]);
 541                         if (ret) {
 542                                 dev_err(&pdev->dev,
 543                                         "can't put vbus gpio %d as output %d\n",
 544                                         gpio, !pdata->vbus_pin_active_low[i]);
 545                                 gpio_free(gpio);
 546                                 continue;
 547                         }
 548
 549                         ohci_at91_usb_set_power(pdata, i, 1);
 550                 }
 551
 552                 at91_for_each_port(i) {
 553                         if (!gpio_is_valid(pdata->overcurrent_pin[i]))
 554                                 continue;
 555                         gpio = pdata->overcurrent_pin[i];
 556
 557                         ret = gpio_request(gpio, "ohci_overcurrent");
 558                         if (ret) {
 559                                 dev_err(&pdev->dev,
 560                                         "can't request overcurrent gpio %d\n",
 561                                         gpio);
 562                                 continue;
 563                         }
 564
 565                         ret = gpio_direction_input(gpio);
 566                         if (ret) {
 567                                 dev_err(&pdev->dev,
 568                                         "can't configure overcurrent gpio %d as input\n",
 569                                         gpio);
 570                                 gpio_free(gpio);
 571                                 continue;
 572                         }
 573
 574                         ret = request_irq(gpio_to_irq(gpio),
 575                                           ohci_hcd_at91_overcurrent_irq,
 576                                           IRQF_SHARED, "ohci_overcurrent", pdev);
 577                         if (ret) {
 578                                 gpio_free(gpio);
 579                                 dev_err(&pdev->dev,
 580                                         "can't get gpio IRQ for overcurrent\n");
 581                         }
 582                 }
 583         }
 584
 585         device_init_wakeup(&pdev->dev, 1);
 586         return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
 587 }
 588
 589 static int ohci_hcd_at91_drv_remove(struct platform_device *pdev)
 590 {
 591         struct at91_usbh_data   *pdata = dev_get_platdata(&pdev->dev);
 592         int                     i;
 593
 594         if (pdata) {
 595                 at91_for_each_port(i) {
 596                         if (!gpio_is_valid(pdata->vbus_pin[i]))
 597                                 continue;
 598                         ohci_at91_usb_set_power(pdata, i, 0);
 599                         gpio_free(pdata->vbus_pin[i]);
 600                 }
 601
 602                 at91_for_each_port(i) {
 603                         if (!gpio_is_valid(pdata->overcurrent_pin[i]))
 604                                 continue;
 605                         free_irq(gpio_to_irq(pdata->overcurrent_pin[i]), pdev);
 606                         gpio_free(pdata->overcurrent_pin[i]);
 607                 }
 608         }
 609
 610         device_init_wakeup(&pdev->dev, 0);
 611         usb_hcd_at91_remove(platform_get_drvdata(pdev), pdev);
 612         return 0;
 613 }
 614
 615 #ifdef CONFIG_PM
 616
 617 static int
 618 ohci_hcd_at91_drv_suspend(struct device *dev)
 619 {
 620         struct usb_hcd  *hcd = dev_get_drvdata(dev);
 621         struct ohci_hcd *ohci = hcd_to_ohci(hcd);
 622         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 623         int             ret;
 624
 625         /*
 626          * Disable wakeup if we are going to sleep with slow clock mode
 627          * enabled.
 628          */
 629         ohci_at91->wakeup = device_may_wakeup(dev)
 630                         && !at91_suspend_entering_slow_clock();
 631
 632         if (ohci_at91->wakeup)
 633                 enable_irq_wake(hcd->irq);
 634
 635         ret = ohci_suspend(hcd, ohci_at91->wakeup);
 636         if (ret) {
 637                 if (ohci_at91->wakeup)
 638                         disable_irq_wake(hcd->irq);
 639                 return ret;
 640         }
 641         /*
 642          * The integrated transceivers seem unable to notice disconnect,
 643          * reconnect, or wakeup without the 48 MHz clock active.  so for
 644          * correctness, always discard connection state (using reset).
 645          *
 646          * REVISIT: some boards will be able to turn VBUS off...
 647          */
 648         if (!ohci_at91->wakeup) {
 649                 ohci->hc_control = ohci_readl(ohci, &ohci->regs->control);
 650                 ohci->hc_control &= OHCI_CTRL_RWC;
 651                 ohci_writel(ohci, ohci->hc_control, &ohci->regs->control);
 652                 ohci->rh_state = OHCI_RH_HALTED;
 653
 654                 /* flush the writes */
 655                 (void) ohci_readl (ohci, &ohci->regs->control);
 656                 at91_stop_clock(ohci_at91);
 657         }
 658
 659         return ret;
 660 }
 661
 662 static int ohci_hcd_at91_drv_resume(struct device *dev)
 663 {
 664         struct usb_hcd  *hcd = dev_get_drvdata(dev);
 665         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 666
 667         if (ohci_at91->wakeup)
 668                 disable_irq_wake(hcd->irq);
 669
 670         at91_start_clock(ohci_at91);
 671
 672         ohci_resume(hcd, false);
 673         return 0;
 674 }
 675 #endif
 676
 677 static SIMPLE_DEV_PM_OPS(ohci_hcd_at91_pm_ops, ohci_hcd_at91_drv_suspend,
 678                                         ohci_hcd_at91_drv_resume);
 679
 680 static struct platform_driver ohci_hcd_at91_driver = {
 681         .probe          = ohci_hcd_at91_drv_probe,
 682         .remove         = ohci_hcd_at91_drv_remove,
 683         .shutdown       = usb_hcd_platform_shutdown,
 684         .driver         = {
 685                 .name   = "at91_ohci",
 686                 .pm     = &ohci_hcd_at91_pm_ops,
 687                 .of_match_table = of_match_ptr(at91_ohci_dt_ids),
 688         },
 689 };
 690
 691 static int __init ohci_at91_init(void)
 692 {
 693         if (usb_disabled())
 694                 return -ENODEV;
 695
 696         pr_info("%s: " DRIVER_DESC "\n", hcd_name);
 697         ohci_init_driver(&ohci_at91_hc_driver, &ohci_at91_drv_overrides);
 698
 699         /*
 700          * The Atmel HW has some unusual quirks, which require Atmel-specific
 701          * workarounds. We override certain hc_driver functions here to
 702          * achieve that. We explicitly do not enhance ohci_driver_overrides to
 703          * allow this more easily, since this is an unusual case, and we don't
 704          * want to encourage others to override these functions by making it
 705          * too easy.
 706          */
 707
 708         ohci_at91_hc_driver.hub_status_data     = ohci_at91_hub_status_data;
 709         ohci_at91_hc_driver.hub_control         = ohci_at91_hub_control;
 710
 711         return platform_driver_register(&ohci_hcd_at91_driver);
 712 }
 713 module_init(ohci_at91_init);
 714
 715 static void __exit ohci_at91_cleanup(void)
 716 {
 717         platform_driver_unregister(&ohci_hcd_at91_driver);
 718 }
 719 module_exit(ohci_at91_cleanup);
 720
 721 MODULE_DESCRIPTION(DRIVER_DESC);
 722 MODULE_LICENSE("GPL");
 723 MODULE_ALIAS("platform:at91_ohci");