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/mfd/syscon.h>
  25 #include <linux/regmap.h>
  26 #include <linux/usb.h>
  27 #include <linux/usb/hcd.h>
  28 #include <soc/at91/at91_sfr.h>
  29
  30 #include "ohci.h"
  31
  32 #define valid_port(index)       ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS)
  33 #define at91_for_each_port(index)       \
  34                 for ((index) = 0; (index) < AT91_MAX_USBH_PORTS; (index)++)
  35
  36 /* interface, function and usb clocks; sometimes also an AHB clock */
  37 #define hcd_to_ohci_at91_priv(h) \
  38         ((struct ohci_at91_priv *)hcd_to_ohci(h)->priv)
  39
  40 #define AT91_MAX_USBH_PORTS     3
  41 struct at91_usbh_data {
  42         int vbus_pin[AT91_MAX_USBH_PORTS];      /* port power-control pin */
  43         int overcurrent_pin[AT91_MAX_USBH_PORTS];
  44         u8 ports;                               /* number of ports on root hub */
  45         u8 overcurrent_supported;
  46         u8 vbus_pin_active_low[AT91_MAX_USBH_PORTS];
  47         u8 overcurrent_status[AT91_MAX_USBH_PORTS];
  48         u8 overcurrent_changed[AT91_MAX_USBH_PORTS];
  49 };
  50
  51 struct ohci_at91_caps {
  52         bool suspend_ctrl;
  53 };
  54
  55 struct ohci_at91_priv {
  56         struct clk *iclk;
  57         struct clk *fclk;
  58         struct clk *hclk;
  59         bool clocked;
  60         bool wakeup;            /* Saved wake-up state for resume */
  61         const struct ohci_at91_caps *caps;
  62         struct regmap *sfr_regmap;
  63 };
  64 /* interface and function clocks; sometimes also an AHB clock */
  65
  66 #define DRIVER_DESC "OHCI Atmel driver"
  67
  68 static const char hcd_name[] = "ohci-atmel";
  69
  70 static struct hc_driver __read_mostly ohci_at91_hc_driver;
  71
  72 static const struct ohci_driver_overrides ohci_at91_drv_overrides __initconst = {
  73         .extra_priv_size = sizeof(struct ohci_at91_priv),
  74 };
  75
  76 extern int usb_disabled(void);
  77
  78 /*-------------------------------------------------------------------------*/
  79
  80 static void at91_start_clock(struct ohci_at91_priv *ohci_at91)
  81 {
  82         if (ohci_at91->clocked)
  83                 return;
  84
  85         clk_set_rate(ohci_at91->fclk, 48000000);
  86         clk_prepare_enable(ohci_at91->hclk);
  87         clk_prepare_enable(ohci_at91->iclk);
  88         clk_prepare_enable(ohci_at91->fclk);
  89         ohci_at91->clocked = true;
  90 }
  91
  92 static void at91_stop_clock(struct ohci_at91_priv *ohci_at91)
  93 {
  94         if (!ohci_at91->clocked)
  95                 return;
  96
  97         clk_disable_unprepare(ohci_at91->fclk);
  98         clk_disable_unprepare(ohci_at91->iclk);
  99         clk_disable_unprepare(ohci_at91->hclk);
 100         ohci_at91->clocked = false;
 101 }
 102
 103 static void at91_start_hc(struct platform_device *pdev)
 104 {
 105         struct usb_hcd *hcd = platform_get_drvdata(pdev);
 106         struct ohci_regs __iomem *regs = hcd->regs;
 107         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 108
 109         dev_dbg(&pdev->dev, "start\n");
 110
 111         /*
 112          * Start the USB clocks.
 113          */
 114         at91_start_clock(ohci_at91);
 115
 116         /*
 117          * The USB host controller must remain in reset.
 118          */
 119         writel(0, &regs->control);
 120 }
 121
 122 static void at91_stop_hc(struct platform_device *pdev)
 123 {
 124         struct usb_hcd *hcd = platform_get_drvdata(pdev);
 125         struct ohci_regs __iomem *regs = hcd->regs;
 126         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 127
 128         dev_dbg(&pdev->dev, "stop\n");
 129
 130         /*
 131          * Put the USB host controller into reset.
 132          */
 133         writel(0, &regs->control);
 134
 135         /*
 136          * Stop the USB clocks.
 137          */
 138         at91_stop_clock(ohci_at91);
 139 }
 140
 141
 142 /*-------------------------------------------------------------------------*/
 143
 144 struct regmap *at91_dt_syscon_sfr(void)
 145 {
 146         struct regmap *regmap;
 147
 148         regmap = syscon_regmap_lookup_by_compatible("atmel,sama5d2-sfr");
 149         if (IS_ERR(regmap))
 150                 regmap = NULL;
 151
 152         return regmap;
 153 }
 154
 155 static void usb_hcd_at91_remove (struct usb_hcd *, struct platform_device *);
 156
 157 /* configure so an HC device and id are always provided */
 158 /* always called with process context; sleeping is OK */
 159
 160
 161 /**
 162  * usb_hcd_at91_probe - initialize AT91-based HCDs
 163  * Context: !in_interrupt()
 164  *
 165  * Allocates basic resources for this USB host controller, and
 166  * then invokes the start() method for the HCD associated with it
 167  * through the hotplug entry's driver_data.
 168  */
 169 static int usb_hcd_at91_probe(const struct hc_driver *driver,
 170                         struct platform_device *pdev)
 171 {
 172         struct at91_usbh_data *board;
 173         struct ohci_hcd *ohci;
 174         int retval;
 175         struct usb_hcd *hcd;
 176         struct ohci_at91_priv *ohci_at91;
 177         struct device *dev = &pdev->dev;
 178         struct resource *res;
 179         int irq;
 180
 181         irq = platform_get_irq(pdev, 0);
 182         if (irq < 0) {
 183                 dev_dbg(dev, "hcd probe: missing irq resource\n");
 184                 return irq;
 185         }
 186
 187         hcd = usb_create_hcd(driver, dev, "at91");
 188         if (!hcd)
 189                 return -ENOMEM;
 190         ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 191
 192         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 193         hcd->regs = devm_ioremap_resource(dev, res);
 194         if (IS_ERR(hcd->regs)) {
 195                 retval = PTR_ERR(hcd->regs);
 196                 goto err;
 197         }
 198         hcd->rsrc_start = res->start;
 199         hcd->rsrc_len = resource_size(res);
 200
 201         ohci_at91->iclk = devm_clk_get(dev, "ohci_clk");
 202         if (IS_ERR(ohci_at91->iclk)) {
 203                 dev_err(dev, "failed to get ohci_clk\n");
 204                 retval = PTR_ERR(ohci_at91->iclk);
 205                 goto err;
 206         }
 207         ohci_at91->fclk = devm_clk_get(dev, "uhpck");
 208         if (IS_ERR(ohci_at91->fclk)) {
 209                 dev_err(dev, "failed to get uhpck\n");
 210                 retval = PTR_ERR(ohci_at91->fclk);
 211                 goto err;
 212         }
 213         ohci_at91->hclk = devm_clk_get(dev, "hclk");
 214         if (IS_ERR(ohci_at91->hclk)) {
 215                 dev_err(dev, "failed to get hclk\n");
 216                 retval = PTR_ERR(ohci_at91->hclk);
 217                 goto err;
 218         }
 219
 220         ohci_at91->caps = (const struct ohci_at91_caps *)
 221                           of_device_get_match_data(&pdev->dev);
 222         if (!ohci_at91->caps)
 223                 return -ENODEV;
 224
 225         if (ohci_at91->caps->suspend_ctrl) {
 226                 ohci_at91->sfr_regmap = at91_dt_syscon_sfr();
 227                 if (!ohci_at91->sfr_regmap)
 228                         dev_warn(dev, "failed to find sfr node\n");
 229         }
 230
 231         board = hcd->self.controller->platform_data;
 232         ohci = hcd_to_ohci(hcd);
 233         ohci->num_ports = board->ports;
 234         at91_start_hc(pdev);
 235
 236         retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
 237         if (retval == 0) {
 238                 device_wakeup_enable(hcd->self.controller);
 239                 return retval;
 240         }
 241
 242         /* Error handling */
 243         at91_stop_hc(pdev);
 244
 245  err:
 246         usb_put_hcd(hcd);
 247         return retval;
 248 }
 249
 250
 251 /* may be called with controller, bus, and devices active */
 252
 253 /**
 254  * usb_hcd_at91_remove - shutdown processing for AT91-based HCDs
 255  * @dev: USB Host Controller being removed
 256  * Context: !in_interrupt()
 257  *
 258  * Reverses the effect of usb_hcd_at91_probe(), first invoking
 259  * the HCD's stop() method.  It is always called from a thread
 260  * context, "rmmod" or something similar.
 261  *
 262  */
 263 static void usb_hcd_at91_remove(struct usb_hcd *hcd,
 264                                 struct platform_device *pdev)
 265 {
 266         usb_remove_hcd(hcd);
 267         at91_stop_hc(pdev);
 268         usb_put_hcd(hcd);
 269 }
 270
 271 /*-------------------------------------------------------------------------*/
 272 static void ohci_at91_usb_set_power(struct at91_usbh_data *pdata, int port, int enable)
 273 {
 274         if (!valid_port(port))
 275                 return;
 276
 277         if (!gpio_is_valid(pdata->vbus_pin[port]))
 278                 return;
 279
 280         gpio_set_value(pdata->vbus_pin[port],
 281                        pdata->vbus_pin_active_low[port] ^ enable);
 282 }
 283
 284 static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
 285 {
 286         if (!valid_port(port))
 287                 return -EINVAL;
 288
 289         if (!gpio_is_valid(pdata->vbus_pin[port]))
 290                 return -EINVAL;
 291
 292         return gpio_get_value(pdata->vbus_pin[port]) ^
 293                 pdata->vbus_pin_active_low[port];
 294 }
 295
 296 /*
 297  * Update the status data from the hub with the over-current indicator change.
 298  */
 299 static int ohci_at91_hub_status_data(struct usb_hcd *hcd, char *buf)
 300 {
 301         struct at91_usbh_data *pdata = hcd->self.controller->platform_data;
 302         int length = ohci_hub_status_data(hcd, buf);
 303         int port;
 304
 305         at91_for_each_port(port) {
 306                 if (pdata->overcurrent_changed[port]) {
 307                         if (!length)
 308                                 length = 1;
 309                         buf[0] |= 1 << (port + 1);
 310                 }
 311         }
 312
 313         return length;
 314 }
 315
 316 /*
 317  * Look at the control requests to the root hub and see if we need to override.
 318  */
 319 static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 320                                  u16 wIndex, char *buf, u16 wLength)
 321 {
 322         struct at91_usbh_data *pdata = dev_get_platdata(hcd->self.controller);
 323         struct usb_hub_descriptor *desc;
 324         int ret = -EINVAL;
 325         u32 *data = (u32 *)buf;
 326
 327         dev_dbg(hcd->self.controller,
 328                 "ohci_at91_hub_control(%p,0x%04x,0x%04x,0x%04x,%p,%04x)\n",
 329                 hcd, typeReq, wValue, wIndex, buf, wLength);
 330
 331         wIndex--;
 332
 333         switch (typeReq) {
 334         case SetPortFeature:
 335                 if (wValue == USB_PORT_FEAT_POWER) {
 336                         dev_dbg(hcd->self.controller, "SetPortFeat: POWER\n");
 337                         if (valid_port(wIndex)) {
 338                                 ohci_at91_usb_set_power(pdata, wIndex, 1);
 339                                 ret = 0;
 340                         }
 341
 342                         goto out;
 343                 }
 344                 break;
 345
 346         case ClearPortFeature:
 347                 switch (wValue) {
 348                 case USB_PORT_FEAT_C_OVER_CURRENT:
 349                         dev_dbg(hcd->self.controller,
 350                                 "ClearPortFeature: C_OVER_CURRENT\n");
 351
 352                         if (valid_port(wIndex)) {
 353                                 pdata->overcurrent_changed[wIndex] = 0;
 354                                 pdata->overcurrent_status[wIndex] = 0;
 355                         }
 356
 357                         goto out;
 358
 359                 case USB_PORT_FEAT_OVER_CURRENT:
 360                         dev_dbg(hcd->self.controller,
 361                                 "ClearPortFeature: OVER_CURRENT\n");
 362
 363                         if (valid_port(wIndex))
 364                                 pdata->overcurrent_status[wIndex] = 0;
 365
 366                         goto out;
 367
 368                 case USB_PORT_FEAT_POWER:
 369                         dev_dbg(hcd->self.controller,
 370                                 "ClearPortFeature: POWER\n");
 371
 372                         if (valid_port(wIndex)) {
 373                                 ohci_at91_usb_set_power(pdata, wIndex, 0);
 374                                 return 0;
 375                         }
 376                 }
 377                 break;
 378         }
 379
 380         ret = ohci_hub_control(hcd, typeReq, wValue, wIndex + 1, buf, wLength);
 381         if (ret)
 382                 goto out;
 383
 384         switch (typeReq) {
 385         case GetHubDescriptor:
 386
 387                 /* update the hub's descriptor */
 388
 389                 desc = (struct usb_hub_descriptor *)buf;
 390
 391                 dev_dbg(hcd->self.controller, "wHubCharacteristics 0x%04x\n",
 392                         desc->wHubCharacteristics);
 393
 394                 /* remove the old configurations for power-switching, and
 395                  * over-current protection, and insert our new configuration
 396                  */
 397
 398                 desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_LPSM);
 399                 desc->wHubCharacteristics |=
 400                         cpu_to_le16(HUB_CHAR_INDV_PORT_LPSM);
 401
 402                 if (pdata->overcurrent_supported) {
 403                         desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_OCPM);
 404                         desc->wHubCharacteristics |=
 405                                 cpu_to_le16(HUB_CHAR_INDV_PORT_OCPM);
 406                 }
 407
 408                 dev_dbg(hcd->self.controller, "wHubCharacteristics after 0x%04x\n",
 409                         desc->wHubCharacteristics);
 410
 411                 return ret;
 412
 413         case GetPortStatus:
 414                 /* check port status */
 415
 416                 dev_dbg(hcd->self.controller, "GetPortStatus(%d)\n", wIndex);
 417
 418                 if (valid_port(wIndex)) {
 419                         if (!ohci_at91_usb_get_power(pdata, wIndex))
 420                                 *data &= ~cpu_to_le32(RH_PS_PPS);
 421
 422                         if (pdata->overcurrent_changed[wIndex])
 423                                 *data |= cpu_to_le32(RH_PS_OCIC);
 424
 425                         if (pdata->overcurrent_status[wIndex])
 426                                 *data |= cpu_to_le32(RH_PS_POCI);
 427                 }
 428         }
 429
 430  out:
 431         return ret;
 432 }
 433
 434 /*-------------------------------------------------------------------------*/
 435
 436 static irqreturn_t ohci_hcd_at91_overcurrent_irq(int irq, void *data)
 437 {
 438         struct platform_device *pdev = data;
 439         struct at91_usbh_data *pdata = dev_get_platdata(&pdev->dev);
 440         int val, gpio, port;
 441
 442         /* From the GPIO notifying the over-current situation, find
 443          * out the corresponding port */
 444         at91_for_each_port(port) {
 445                 if (gpio_is_valid(pdata->overcurrent_pin[port]) &&
 446                                 gpio_to_irq(pdata->overcurrent_pin[port]) == irq) {
 447                         gpio = pdata->overcurrent_pin[port];
 448                         break;
 449                 }
 450         }
 451
 452         if (port == AT91_MAX_USBH_PORTS) {
 453                 dev_err(& pdev->dev, "overcurrent interrupt from unknown GPIO\n");
 454                 return IRQ_HANDLED;
 455         }
 456
 457         val = gpio_get_value(gpio);
 458
 459         /* When notified of an over-current situation, disable power
 460            on the corresponding port, and mark this port in
 461            over-current. */
 462         if (!val) {
 463                 ohci_at91_usb_set_power(pdata, port, 0);
 464                 pdata->overcurrent_status[port]  = 1;
 465                 pdata->overcurrent_changed[port] = 1;
 466         }
 467
 468         dev_dbg(& pdev->dev, "overcurrent situation %s\n",
 469                 val ? "exited" : "notified");
 470
 471         return IRQ_HANDLED;
 472 }
 473
 474 static const struct ohci_at91_caps at91rm9200_caps = {
 475         .suspend_ctrl = false,
 476 };
 477
 478 static const struct ohci_at91_caps sama5d2_caps = {
 479         .suspend_ctrl = true,
 480 };
 481
 482 static const struct of_device_id at91_ohci_dt_ids[] = {
 483         { .compatible = "atmel,at91rm9200-ohci", .data = &at91rm9200_caps },
 484         { .compatible = "atmel,sama5d2-ohci", .data = &sama5d2_caps },
 485         { /* sentinel */ }
 486 };
 487
 488 MODULE_DEVICE_TABLE(of, at91_ohci_dt_ids);
 489
 490 /*-------------------------------------------------------------------------*/
 491
 492 static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
 493 {
 494         struct device_node *np = pdev->dev.of_node;
 495         struct at91_usbh_data   *pdata;
 496         int                     i;
 497         int                     gpio;
 498         int                     ret;
 499         enum of_gpio_flags      flags;
 500         u32                     ports;
 501
 502         /* Right now device-tree probed devices don't get dma_mask set.
 503          * Since shared usb code relies on it, set it here for now.
 504          * Once we have dma capability bindings this can go away.
 505          */
 506         ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 507         if (ret)
 508                 return ret;
 509
 510         pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 511         if (!pdata)
 512                 return -ENOMEM;
 513
 514         pdev->dev.platform_data = pdata;
 515
 516         if (!of_property_read_u32(np, "num-ports", &ports))
 517                 pdata->ports = ports;
 518
 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                         continue;
 528                 }
 529
 530                 gpio = of_get_named_gpio_flags(np, "atmel,vbus-gpio", i,
 531                                                &flags);
 532                 pdata->vbus_pin[i] = gpio;
 533                 if (!gpio_is_valid(gpio))
 534                         continue;
 535                 pdata->vbus_pin_active_low[i] = flags & OF_GPIO_ACTIVE_LOW;
 536
 537                 ret = gpio_request(gpio, "ohci_vbus");
 538                 if (ret) {
 539                         dev_err(&pdev->dev,
 540                                 "can't request vbus gpio %d\n", gpio);
 541                         continue;
 542                 }
 543                 ret = gpio_direction_output(gpio,
 544                                         !pdata->vbus_pin_active_low[i]);
 545                 if (ret) {
 546                         dev_err(&pdev->dev,
 547                                 "can't put vbus gpio %d as output %d\n",
 548                                 gpio, !pdata->vbus_pin_active_low[i]);
 549                         gpio_free(gpio);
 550                         continue;
 551                 }
 552
 553                 ohci_at91_usb_set_power(pdata, i, 1);
 554         }
 555
 556         at91_for_each_port(i) {
 557                 if (i >= pdata->ports)
 558                         break;
 559
 560                 pdata->overcurrent_pin[i] =
 561                         of_get_named_gpio_flags(np, "atmel,oc-gpio", i, &flags);
 562
 563                 if (!gpio_is_valid(pdata->overcurrent_pin[i]))
 564                         continue;
 565                 gpio = pdata->overcurrent_pin[i];
 566
 567                 ret = gpio_request(gpio, "ohci_overcurrent");
 568                 if (ret) {
 569                         dev_err(&pdev->dev,
 570                                 "can't request overcurrent gpio %d\n",
 571                                 gpio);
 572                         continue;
 573                 }
 574
 575                 ret = gpio_direction_input(gpio);
 576                 if (ret) {
 577                         dev_err(&pdev->dev,
 578                                 "can't configure overcurrent gpio %d as input\n",
 579                                 gpio);
 580                         gpio_free(gpio);
 581                         continue;
 582                 }
 583
 584                 ret = request_irq(gpio_to_irq(gpio),
 585                                   ohci_hcd_at91_overcurrent_irq,
 586                                   IRQF_SHARED, "ohci_overcurrent", pdev);
 587                 if (ret) {
 588                         gpio_free(gpio);
 589                         dev_err(&pdev->dev,
 590                                 "can't get gpio IRQ for overcurrent\n");
 591                 }
 592         }
 593
 594         device_init_wakeup(&pdev->dev, 1);
 595         return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
 596 }
 597
 598 static int ohci_hcd_at91_drv_remove(struct platform_device *pdev)
 599 {
 600         struct at91_usbh_data   *pdata = dev_get_platdata(&pdev->dev);
 601         int                     i;
 602
 603         if (pdata) {
 604                 at91_for_each_port(i) {
 605                         if (!gpio_is_valid(pdata->vbus_pin[i]))
 606                                 continue;
 607                         ohci_at91_usb_set_power(pdata, i, 0);
 608                         gpio_free(pdata->vbus_pin[i]);
 609                 }
 610
 611                 at91_for_each_port(i) {
 612                         if (!gpio_is_valid(pdata->overcurrent_pin[i]))
 613                                 continue;
 614                         free_irq(gpio_to_irq(pdata->overcurrent_pin[i]), pdev);
 615                         gpio_free(pdata->overcurrent_pin[i]);
 616                 }
 617         }
 618
 619         device_init_wakeup(&pdev->dev, 0);
 620         usb_hcd_at91_remove(platform_get_drvdata(pdev), pdev);
 621         return 0;
 622 }
 623
 624 static int ohci_at91_port_ctrl(struct regmap *regmap, bool enable)
 625 {
 626         u32 regval;
 627         int ret;
 628
 629         if (!regmap)
 630                 return -EINVAL;
 631
 632         ret = regmap_read(regmap, SFR_OHCIICR, &regval);
 633         if (ret)
 634                 return ret;
 635
 636         if (enable)
 637                 regval &= ~SFR_OHCIICR_USB_SUSPEND;
 638         else
 639                 regval |= SFR_OHCIICR_USB_SUSPEND;
 640
 641         regmap_write(regmap, SFR_OHCIICR, regval);
 642
 643         return 0;
 644 }
 645
 646 static int ohci_at91_port_suspend(struct regmap *regmap)
 647 {
 648         return ohci_at91_port_ctrl(regmap, false);
 649 }
 650
 651 static int ohci_at91_port_resume(struct regmap *regmap)
 652 {
 653         return ohci_at91_port_ctrl(regmap, true);
 654 }
 655
 656 static int __maybe_unused
 657 ohci_hcd_at91_drv_suspend(struct device *dev)
 658 {
 659         struct usb_hcd  *hcd = dev_get_drvdata(dev);
 660         struct ohci_hcd *ohci = hcd_to_ohci(hcd);
 661         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 662         int             ret;
 663
 664         /*
 665          * Disable wakeup if we are going to sleep with slow clock mode
 666          * enabled.
 667          */
 668         ohci_at91->wakeup = device_may_wakeup(dev)
 669                         && !at91_suspend_entering_slow_clock();
 670
 671         if (ohci_at91->wakeup)
 672                 enable_irq_wake(hcd->irq);
 673
 674         ret = ohci_suspend(hcd, ohci_at91->wakeup);
 675         if (ret) {
 676                 if (ohci_at91->wakeup)
 677                         disable_irq_wake(hcd->irq);
 678                 return ret;
 679         }
 680         /*
 681          * The integrated transceivers seem unable to notice disconnect,
 682          * reconnect, or wakeup without the 48 MHz clock active.  so for
 683          * correctness, always discard connection state (using reset).
 684          *
 685          * REVISIT: some boards will be able to turn VBUS off...
 686          */
 687         if (!ohci_at91->wakeup) {
 688                 ohci->hc_control = ohci_readl(ohci, &ohci->regs->control);
 689                 ohci->hc_control &= OHCI_CTRL_RWC;
 690                 ohci_writel(ohci, ohci->hc_control, &ohci->regs->control);
 691                 ohci->rh_state = OHCI_RH_HALTED;
 692
 693                 if (ohci_at91->caps->suspend_ctrl)
 694                         ohci_at91_port_suspend(ohci_at91->sfr_regmap);
 695
 696                 /* flush the writes */
 697                 (void) ohci_readl (ohci, &ohci->regs->control);
 698                 at91_stop_clock(ohci_at91);
 699         }
 700
 701         return ret;
 702 }
 703
 704 static int __maybe_unused
 705 ohci_hcd_at91_drv_resume(struct device *dev)
 706 {
 707         struct usb_hcd  *hcd = dev_get_drvdata(dev);
 708         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 709
 710         if (ohci_at91->wakeup)
 711                 disable_irq_wake(hcd->irq);
 712
 713         at91_start_clock(ohci_at91);
 714
 715         if (ohci_at91->caps->suspend_ctrl)
 716                 ohci_at91_port_resume(ohci_at91->sfr_regmap);
 717
 718         ohci_resume(hcd, false);
 719         return 0;
 720 }
 721
 722 static SIMPLE_DEV_PM_OPS(ohci_hcd_at91_pm_ops, ohci_hcd_at91_drv_suspend,
 723                                         ohci_hcd_at91_drv_resume);
 724
 725 static struct platform_driver ohci_hcd_at91_driver = {
 726         .probe          = ohci_hcd_at91_drv_probe,
 727         .remove         = ohci_hcd_at91_drv_remove,
 728         .shutdown       = usb_hcd_platform_shutdown,
 729         .driver         = {
 730                 .name   = "at91_ohci",
 731                 .pm     = &ohci_hcd_at91_pm_ops,
 732                 .of_match_table = at91_ohci_dt_ids,
 733         },
 734 };
 735
 736 static int __init ohci_at91_init(void)
 737 {
 738         if (usb_disabled())
 739                 return -ENODEV;
 740
 741         pr_info("%s: " DRIVER_DESC "\n", hcd_name);
 742         ohci_init_driver(&ohci_at91_hc_driver, &ohci_at91_drv_overrides);
 743
 744         /*
 745          * The Atmel HW has some unusual quirks, which require Atmel-specific
 746          * workarounds. We override certain hc_driver functions here to
 747          * achieve that. We explicitly do not enhance ohci_driver_overrides to
 748          * allow this more easily, since this is an unusual case, and we don't
 749          * want to encourage others to override these functions by making it
 750          * too easy.
 751          */
 752
 753         ohci_at91_hc_driver.hub_status_data     = ohci_at91_hub_status_data;
 754         ohci_at91_hc_driver.hub_control         = ohci_at91_hub_control;
 755
 756         return platform_driver_register(&ohci_hcd_at91_driver);
 757 }
 758 module_init(ohci_at91_init);
 759
 760 static void __exit ohci_at91_cleanup(void)
 761 {
 762         platform_driver_unregister(&ohci_hcd_at91_driver);
 763 }
 764 module_exit(ohci_at91_cleanup);
 765
 766 MODULE_DESCRIPTION(DRIVER_DESC);
 767 MODULE_LICENSE("GPL");
 768 MODULE_ALIAS("platform:at91_ohci");