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