drivers/usb/host/ohci-at91.c

   1 // SPDX-License-Identifier: GPL-1.0+
   2 /*
   3  * OHCI HCD (Host Controller Driver) for USB.
   4  *
   5  *  Copyright (C) 2004 SAN People (Pty) Ltd.
   6  *  Copyright (C) 2005 Thibaut VARENE <varenet@parisc-linux.org>
   7  *
   8  * AT91 Bus Glue
   9  *
  10  * Based on fragments of 2.4 driver by Rick Bronson.
  11  * Based on ohci-omap.c
  12  *
  13  * This file is licenced under the GPL.
  14  */
  15
  16 #include <linux/clk.h>
  17 #include <linux/dma-mapping.h>
  18 #include <linux/gpio/consumer.h>
  19 #include <linux/of_platform.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/platform_data/atmel.h>
  22 #include <linux/io.h>
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/mfd/syscon.h>
  26 #include <linux/regmap.h>
  27 #include <linux/usb.h>
  28 #include <linux/usb/hcd.h>
  29 #include <soc/at91/atmel-sfr.h>
  30
  31 #include "ohci.h"
  32
  33 #define valid_port(index)       ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS)
  34 #define at91_for_each_port(index)       \
  35                 for ((index) = 0; (index) < AT91_MAX_USBH_PORTS; (index)++)
  36
  37 /* interface, function and usb clocks; sometimes also an AHB clock */
  38 #define hcd_to_ohci_at91_priv(h) \
  39         ((struct ohci_at91_priv *)hcd_to_ohci(h)->priv)
  40
  41 #define AT91_MAX_USBH_PORTS     3
  42 struct at91_usbh_data {
  43         struct gpio_desc *vbus_pin[AT91_MAX_USBH_PORTS];
  44         struct gpio_desc *overcurrent_pin[AT91_MAX_USBH_PORTS];
  45         u8 ports;                               /* number of ports on root hub */
  46         u8 overcurrent_supported;
  47         u8 overcurrent_status[AT91_MAX_USBH_PORTS];
  48         u8 overcurrent_changed[AT91_MAX_USBH_PORTS];
  49 };
  50
  51 struct ohci_at91_priv {
  52         struct clk *iclk;
  53         struct clk *fclk;
  54         struct clk *hclk;
  55         bool clocked;
  56         bool wakeup;            /* Saved wake-up state for resume */
  57         struct regmap *sfr_regmap;
  58 };
  59 /* interface and function clocks; sometimes also an AHB clock */
  60
  61 #define DRIVER_DESC "OHCI Atmel driver"
  62
  63 static const char hcd_name[] = "ohci-atmel";
  64
  65 static struct hc_driver __read_mostly ohci_at91_hc_driver;
  66
  67 static const struct ohci_driver_overrides ohci_at91_drv_overrides __initconst = {
  68         .extra_priv_size = sizeof(struct ohci_at91_priv),
  69 };
  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_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 119
 120         dev_dbg(&pdev->dev, "stop\n");
 121
 122         /*
 123          * Put the USB host controller into reset.
 124          */
 125         usb_hcd_platform_shutdown(pdev);
 126
 127         /*
 128          * Stop the USB clocks.
 129          */
 130         at91_stop_clock(ohci_at91);
 131 }
 132
 133
 134 /*-------------------------------------------------------------------------*/
 135
 136 static void usb_hcd_at91_remove (struct usb_hcd *, struct platform_device *);
 137
 138 static struct regmap *at91_dt_syscon_sfr(void)
 139 {
 140         struct regmap *regmap;
 141
 142         regmap = syscon_regmap_lookup_by_compatible("atmel,sama5d2-sfr");
 143         if (IS_ERR(regmap)) {
 144                 regmap = syscon_regmap_lookup_by_compatible("microchip,sam9x60-sfr");
 145                 if (IS_ERR(regmap))
 146                         regmap = NULL;
 147         }
 148
 149         return regmap;
 150 }
 151
 152 /* configure so an HC device and id are always provided */
 153 /* always called with process context; sleeping is OK */
 154
 155
 156 /*
 157  * usb_hcd_at91_probe - initialize AT91-based HCDs
 158  * Context: !in_interrupt()
 159  *
 160  * Allocates basic resources for this USB host controller, and
 161  * then invokes the start() method for the HCD associated with it
 162  * through the hotplug entry's driver_data.
 163  */
 164 static int usb_hcd_at91_probe(const struct hc_driver *driver,
 165                         struct platform_device *pdev)
 166 {
 167         struct at91_usbh_data *board;
 168         struct ohci_hcd *ohci;
 169         int retval;
 170         struct usb_hcd *hcd;
 171         struct ohci_at91_priv *ohci_at91;
 172         struct device *dev = &pdev->dev;
 173         struct resource *res;
 174         int irq;
 175
 176         irq = platform_get_irq(pdev, 0);
 177         if (irq < 0) {
 178                 dev_dbg(dev, "hcd probe: missing irq resource\n");
 179                 return irq;
 180         }
 181
 182         hcd = usb_create_hcd(driver, dev, "at91");
 183         if (!hcd)
 184                 return -ENOMEM;
 185         ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 186
 187         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 188         hcd->regs = devm_ioremap_resource(dev, res);
 189         if (IS_ERR(hcd->regs)) {
 190                 retval = PTR_ERR(hcd->regs);
 191                 goto err;
 192         }
 193         hcd->rsrc_start = res->start;
 194         hcd->rsrc_len = resource_size(res);
 195
 196         ohci_at91->iclk = devm_clk_get(dev, "ohci_clk");
 197         if (IS_ERR(ohci_at91->iclk)) {
 198                 dev_err(dev, "failed to get ohci_clk\n");
 199                 retval = PTR_ERR(ohci_at91->iclk);
 200                 goto err;
 201         }
 202         ohci_at91->fclk = devm_clk_get(dev, "uhpck");
 203         if (IS_ERR(ohci_at91->fclk)) {
 204                 dev_err(dev, "failed to get uhpck\n");
 205                 retval = PTR_ERR(ohci_at91->fclk);
 206                 goto err;
 207         }
 208         ohci_at91->hclk = devm_clk_get(dev, "hclk");
 209         if (IS_ERR(ohci_at91->hclk)) {
 210                 dev_err(dev, "failed to get hclk\n");
 211                 retval = PTR_ERR(ohci_at91->hclk);
 212                 goto err;
 213         }
 214
 215         ohci_at91->sfr_regmap = at91_dt_syscon_sfr();
 216         if (!ohci_at91->sfr_regmap)
 217                 dev_dbg(dev, "failed to find sfr node\n");
 218
 219         board = hcd->self.controller->platform_data;
 220         ohci = hcd_to_ohci(hcd);
 221         ohci->num_ports = board->ports;
 222         at91_start_hc(pdev);
 223
 224         /*
 225          * The RemoteWakeupConnected bit has to be set explicitly
 226          * before calling ohci_run. The reset value of this bit is 0.
 227          */
 228         ohci->hc_control = OHCI_CTRL_RWC;
 229
 230         retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
 231         if (retval == 0) {
 232                 device_wakeup_enable(hcd->self.controller);
 233                 return retval;
 234         }
 235
 236         /* Error handling */
 237         at91_stop_hc(pdev);
 238
 239  err:
 240         usb_put_hcd(hcd);
 241         return retval;
 242 }
 243
 244
 245 /* may be called with controller, bus, and devices active */
 246
 247 /*
 248  * usb_hcd_at91_remove - shutdown processing for AT91-based HCDs
 249  * Context: !in_interrupt()
 250  *
 251  * Reverses the effect of usb_hcd_at91_probe(), first invoking
 252  * the HCD's stop() method.  It is always called from a thread
 253  * context, "rmmod" or something similar.
 254  *
 255  */
 256 static void usb_hcd_at91_remove(struct usb_hcd *hcd,
 257                                 struct platform_device *pdev)
 258 {
 259         usb_remove_hcd(hcd);
 260         at91_stop_hc(pdev);
 261         usb_put_hcd(hcd);
 262 }
 263
 264 /*-------------------------------------------------------------------------*/
 265 static void ohci_at91_usb_set_power(struct at91_usbh_data *pdata, int port, int enable)
 266 {
 267         if (!valid_port(port))
 268                 return;
 269
 270         gpiod_set_value(pdata->vbus_pin[port], enable);
 271 }
 272
 273 static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
 274 {
 275         if (!valid_port(port))
 276                 return -EINVAL;
 277
 278         return gpiod_get_value(pdata->vbus_pin[port]);
 279 }
 280
 281 /*
 282  * Update the status data from the hub with the over-current indicator change.
 283  */
 284 static int ohci_at91_hub_status_data(struct usb_hcd *hcd, char *buf)
 285 {
 286         struct at91_usbh_data *pdata = hcd->self.controller->platform_data;
 287         int length = ohci_hub_status_data(hcd, buf);
 288         int port;
 289
 290         at91_for_each_port(port) {
 291                 if (pdata->overcurrent_changed[port]) {
 292                         if (!length)
 293                                 length = 1;
 294                         buf[0] |= 1 << (port + 1);
 295                 }
 296         }
 297
 298         return length;
 299 }
 300
 301 static int ohci_at91_port_suspend(struct regmap *regmap, u8 set)
 302 {
 303         u32 regval;
 304         int ret;
 305
 306         if (!regmap)
 307                 return 0;
 308
 309         ret = regmap_read(regmap, AT91_SFR_OHCIICR, &regval);
 310         if (ret)
 311                 return ret;
 312
 313         if (set)
 314                 regval |= AT91_OHCIICR_USB_SUSPEND;
 315         else
 316                 regval &= ~AT91_OHCIICR_USB_SUSPEND;
 317
 318         regmap_write(regmap, AT91_SFR_OHCIICR, regval);
 319
 320         return 0;
 321 }
 322
 323 /*
 324  * Look at the control requests to the root hub and see if we need to override.
 325  */
 326 static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 327                                  u16 wIndex, char *buf, u16 wLength)
 328 {
 329         struct at91_usbh_data *pdata = dev_get_platdata(hcd->self.controller);
 330         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 331         struct usb_hub_descriptor *desc;
 332         int ret = -EINVAL;
 333         u32 *data = (u32 *)buf;
 334
 335         dev_dbg(hcd->self.controller,
 336                 "ohci_at91_hub_control(%p,0x%04x,0x%04x,0x%04x,%p,%04x)\n",
 337                 hcd, typeReq, wValue, wIndex, buf, wLength);
 338
 339         wIndex--;
 340
 341         switch (typeReq) {
 342         case SetPortFeature:
 343                 switch (wValue) {
 344                 case USB_PORT_FEAT_POWER:
 345                         dev_dbg(hcd->self.controller, "SetPortFeat: POWER\n");
 346                         if (valid_port(wIndex)) {
 347                                 ohci_at91_usb_set_power(pdata, wIndex, 1);
 348                                 ret = 0;
 349                         }
 350
 351                         goto out;
 352
 353                 case USB_PORT_FEAT_SUSPEND:
 354                         dev_dbg(hcd->self.controller, "SetPortFeat: SUSPEND\n");
 355                         if (valid_port(wIndex) && ohci_at91->sfr_regmap) {
 356                                 ohci_at91_port_suspend(ohci_at91->sfr_regmap,
 357                                                        1);
 358                                 return 0;
 359                         }
 360                         break;
 361                 }
 362                 break;
 363
 364         case ClearPortFeature:
 365                 switch (wValue) {
 366                 case USB_PORT_FEAT_C_OVER_CURRENT:
 367                         dev_dbg(hcd->self.controller,
 368                                 "ClearPortFeature: C_OVER_CURRENT\n");
 369
 370                         if (valid_port(wIndex)) {
 371                                 pdata->overcurrent_changed[wIndex] = 0;
 372                                 pdata->overcurrent_status[wIndex] = 0;
 373                         }
 374
 375                         goto out;
 376
 377                 case USB_PORT_FEAT_OVER_CURRENT:
 378                         dev_dbg(hcd->self.controller,
 379                                 "ClearPortFeature: OVER_CURRENT\n");
 380
 381                         if (valid_port(wIndex))
 382                                 pdata->overcurrent_status[wIndex] = 0;
 383
 384                         goto out;
 385
 386                 case USB_PORT_FEAT_POWER:
 387                         dev_dbg(hcd->self.controller,
 388                                 "ClearPortFeature: POWER\n");
 389
 390                         if (valid_port(wIndex)) {
 391                                 ohci_at91_usb_set_power(pdata, wIndex, 0);
 392                                 return 0;
 393                         }
 394                         break;
 395
 396                 case USB_PORT_FEAT_SUSPEND:
 397                         dev_dbg(hcd->self.controller, "ClearPortFeature: SUSPEND\n");
 398                         if (valid_port(wIndex) && ohci_at91->sfr_regmap) {
 399                                 ohci_at91_port_suspend(ohci_at91->sfr_regmap,
 400                                                        0);
 401                                 return 0;
 402                         }
 403                         break;
 404                 }
 405                 break;
 406         }
 407
 408         ret = ohci_hub_control(hcd, typeReq, wValue, wIndex + 1, buf, wLength);
 409         if (ret)
 410                 goto out;
 411
 412         switch (typeReq) {
 413         case GetHubDescriptor:
 414
 415                 /* update the hub's descriptor */
 416
 417                 desc = (struct usb_hub_descriptor *)buf;
 418
 419                 dev_dbg(hcd->self.controller, "wHubCharacteristics 0x%04x\n",
 420                         desc->wHubCharacteristics);
 421
 422                 /* remove the old configurations for power-switching, and
 423                  * over-current protection, and insert our new configuration
 424                  */
 425
 426                 desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_LPSM);
 427                 desc->wHubCharacteristics |=
 428                         cpu_to_le16(HUB_CHAR_INDV_PORT_LPSM);
 429
 430                 if (pdata->overcurrent_supported) {
 431                         desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_OCPM);
 432                         desc->wHubCharacteristics |=
 433                                 cpu_to_le16(HUB_CHAR_INDV_PORT_OCPM);
 434                 }
 435
 436                 dev_dbg(hcd->self.controller, "wHubCharacteristics after 0x%04x\n",
 437                         desc->wHubCharacteristics);
 438
 439                 return ret;
 440
 441         case GetPortStatus:
 442                 /* check port status */
 443
 444                 dev_dbg(hcd->self.controller, "GetPortStatus(%d)\n", wIndex);
 445
 446                 if (valid_port(wIndex)) {
 447                         if (!ohci_at91_usb_get_power(pdata, wIndex))
 448                                 *data &= ~cpu_to_le32(RH_PS_PPS);
 449
 450                         if (pdata->overcurrent_changed[wIndex])
 451                                 *data |= cpu_to_le32(RH_PS_OCIC);
 452
 453                         if (pdata->overcurrent_status[wIndex])
 454                                 *data |= cpu_to_le32(RH_PS_POCI);
 455                 }
 456         }
 457
 458  out:
 459         return ret;
 460 }
 461
 462 /*-------------------------------------------------------------------------*/
 463
 464 static irqreturn_t ohci_hcd_at91_overcurrent_irq(int irq, void *data)
 465 {
 466         struct platform_device *pdev = data;
 467         struct at91_usbh_data *pdata = dev_get_platdata(&pdev->dev);
 468         int val, port;
 469
 470         /* From the GPIO notifying the over-current situation, find
 471          * out the corresponding port */
 472         at91_for_each_port(port) {
 473                 if (gpiod_to_irq(pdata->overcurrent_pin[port]) == irq)
 474                         break;
 475         }
 476
 477         if (port == AT91_MAX_USBH_PORTS) {
 478                 dev_err(& pdev->dev, "overcurrent interrupt from unknown GPIO\n");
 479                 return IRQ_HANDLED;
 480         }
 481
 482         val = gpiod_get_value(pdata->overcurrent_pin[port]);
 483
 484         /* When notified of an over-current situation, disable power
 485            on the corresponding port, and mark this port in
 486            over-current. */
 487         if (!val) {
 488                 ohci_at91_usb_set_power(pdata, port, 0);
 489                 pdata->overcurrent_status[port]  = 1;
 490                 pdata->overcurrent_changed[port] = 1;
 491         }
 492
 493         dev_dbg(& pdev->dev, "overcurrent situation %s\n",
 494                 val ? "exited" : "notified");
 495
 496         return IRQ_HANDLED;
 497 }
 498
 499 static const struct of_device_id at91_ohci_dt_ids[] = {
 500         { .compatible = "atmel,at91rm9200-ohci" },
 501         { /* sentinel */ }
 502 };
 503
 504 MODULE_DEVICE_TABLE(of, at91_ohci_dt_ids);
 505
 506 /*-------------------------------------------------------------------------*/
 507
 508 static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
 509 {
 510         struct device_node *np = pdev->dev.of_node;
 511         struct at91_usbh_data   *pdata;
 512         int                     i;
 513         int                     ret;
 514         int                     err;
 515         u32                     ports;
 516
 517         /* Right now device-tree probed devices don't get dma_mask set.
 518          * Since shared usb code relies on it, set it here for now.
 519          * Once we have dma capability bindings this can go away.
 520          */
 521         ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 522         if (ret)
 523                 return ret;
 524
 525         pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 526         if (!pdata)
 527                 return -ENOMEM;
 528
 529         pdev->dev.platform_data = pdata;
 530
 531         if (!of_property_read_u32(np, "num-ports", &ports))
 532                 pdata->ports = ports;
 533
 534         at91_for_each_port(i) {
 535                 if (i >= pdata->ports)
 536                         break;
 537
 538                 pdata->vbus_pin[i] =
 539                         devm_gpiod_get_index_optional(&pdev->dev, "atmel,vbus",
 540                                                       i, GPIOD_OUT_HIGH);
 541                 if (IS_ERR(pdata->vbus_pin[i])) {
 542                         err = PTR_ERR(pdata->vbus_pin[i]);
 543                         dev_err(&pdev->dev, "unable to claim gpio \"vbus\": %d\n", err);
 544                         continue;
 545                 }
 546         }
 547
 548         at91_for_each_port(i) {
 549                 if (i >= pdata->ports)
 550                         break;
 551
 552                 pdata->overcurrent_pin[i] =
 553                         devm_gpiod_get_index_optional(&pdev->dev, "atmel,oc",
 554                                                       i, GPIOD_IN);
 555                 if (!pdata->overcurrent_pin[i])
 556                         continue;
 557                 if (IS_ERR(pdata->overcurrent_pin[i])) {
 558                         err = PTR_ERR(pdata->overcurrent_pin[i]);
 559                         dev_err(&pdev->dev, "unable to claim gpio \"overcurrent\": %d\n", err);
 560                         continue;
 561                 }
 562
 563                 ret = devm_request_irq(&pdev->dev,
 564                                        gpiod_to_irq(pdata->overcurrent_pin[i]),
 565                                        ohci_hcd_at91_overcurrent_irq,
 566                                        IRQF_SHARED,
 567                                        "ohci_overcurrent", pdev);
 568                 if (ret)
 569                         dev_info(&pdev->dev, "failed to request gpio \"overcurrent\" IRQ\n");
 570         }
 571
 572         device_init_wakeup(&pdev->dev, 1);
 573         return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
 574 }
 575
 576 static int ohci_hcd_at91_drv_remove(struct platform_device *pdev)
 577 {
 578         struct at91_usbh_data   *pdata = dev_get_platdata(&pdev->dev);
 579         int                     i;
 580
 581         if (pdata) {
 582                 at91_for_each_port(i)
 583                         ohci_at91_usb_set_power(pdata, i, 0);
 584         }
 585
 586         device_init_wakeup(&pdev->dev, 0);
 587         usb_hcd_at91_remove(platform_get_drvdata(pdev), pdev);
 588         return 0;
 589 }
 590
 591 static int __maybe_unused
 592 ohci_hcd_at91_drv_suspend(struct device *dev)
 593 {
 594         struct usb_hcd  *hcd = dev_get_drvdata(dev);
 595         struct ohci_hcd *ohci = hcd_to_ohci(hcd);
 596         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 597         int             ret;
 598
 599         /*
 600          * Disable wakeup if we are going to sleep with slow clock mode
 601          * enabled.
 602          */
 603         ohci_at91->wakeup = device_may_wakeup(dev)
 604                         && !at91_suspend_entering_slow_clock();
 605
 606         if (ohci_at91->wakeup)
 607                 enable_irq_wake(hcd->irq);
 608
 609         ret = ohci_suspend(hcd, ohci_at91->wakeup);
 610         if (ret) {
 611                 if (ohci_at91->wakeup)
 612                         disable_irq_wake(hcd->irq);
 613                 return ret;
 614         }
 615         /*
 616          * The integrated transceivers seem unable to notice disconnect,
 617          * reconnect, or wakeup without the 48 MHz clock active.  so for
 618          * correctness, always discard connection state (using reset).
 619          *
 620          * REVISIT: some boards will be able to turn VBUS off...
 621          */
 622         if (!ohci_at91->wakeup) {
 623                 ohci->rh_state = OHCI_RH_HALTED;
 624
 625                 /* flush the writes */
 626                 (void) ohci_readl (ohci, &ohci->regs->control);
 627                 msleep(1);
 628                 ohci_at91_port_suspend(ohci_at91->sfr_regmap, 1);
 629                 at91_stop_clock(ohci_at91);
 630         } else {
 631                 ohci_at91_port_suspend(ohci_at91->sfr_regmap, 1);
 632         }
 633
 634         return ret;
 635 }
 636
 637 static int __maybe_unused
 638 ohci_hcd_at91_drv_resume(struct device *dev)
 639 {
 640         struct usb_hcd  *hcd = dev_get_drvdata(dev);
 641         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 642
 643         ohci_at91_port_suspend(ohci_at91->sfr_regmap, 0);
 644
 645         if (ohci_at91->wakeup)
 646                 disable_irq_wake(hcd->irq);
 647         else
 648                 at91_start_clock(ohci_at91);
 649
 650         /*
 651          * According to the comment in ohci_hcd_at91_drv_suspend()
 652          * we need to do a reset if the 48Mhz clock was stopped,
 653          * that is, if ohci_at91->wakeup is clear. Tell ohci_resume()
 654          * to reset in this case by setting its "hibernated" flag.
 655          */
 656         ohci_resume(hcd, !ohci_at91->wakeup);
 657
 658         return 0;
 659 }
 660
 661 static SIMPLE_DEV_PM_OPS(ohci_hcd_at91_pm_ops, ohci_hcd_at91_drv_suspend,
 662                                         ohci_hcd_at91_drv_resume);
 663
 664 static struct platform_driver ohci_hcd_at91_driver = {
 665         .probe          = ohci_hcd_at91_drv_probe,
 666         .remove         = ohci_hcd_at91_drv_remove,
 667         .shutdown       = usb_hcd_platform_shutdown,
 668         .driver         = {
 669                 .name   = "at91_ohci",
 670                 .pm     = &ohci_hcd_at91_pm_ops,
 671                 .of_match_table = at91_ohci_dt_ids,
 672         },
 673 };
 674
 675 static int __init ohci_at91_init(void)
 676 {
 677         if (usb_disabled())
 678                 return -ENODEV;
 679
 680         pr_info("%s: " DRIVER_DESC "\n", hcd_name);
 681         ohci_init_driver(&ohci_at91_hc_driver, &ohci_at91_drv_overrides);
 682
 683         /*
 684          * The Atmel HW has some unusual quirks, which require Atmel-specific
 685          * workarounds. We override certain hc_driver functions here to
 686          * achieve that. We explicitly do not enhance ohci_driver_overrides to
 687          * allow this more easily, since this is an unusual case, and we don't
 688          * want to encourage others to override these functions by making it
 689          * too easy.
 690          */
 691
 692         ohci_at91_hc_driver.hub_status_data     = ohci_at91_hub_status_data;
 693         ohci_at91_hc_driver.hub_control         = ohci_at91_hub_control;
 694
 695         return platform_driver_register(&ohci_hcd_at91_driver);
 696 }
 697 module_init(ohci_at91_init);
 698
 699 static void __exit ohci_at91_cleanup(void)
 700 {
 701         platform_driver_unregister(&ohci_hcd_at91_driver);
 702 }
 703 module_exit(ohci_at91_cleanup);
 704
 705 MODULE_DESCRIPTION(DRIVER_DESC);
 706 MODULE_LICENSE("GPL");
 707 MODULE_ALIAS("platform:at91_ohci");