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/atmel-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_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 extern int usb_disabled(void);
  72
  73 /*-------------------------------------------------------------------------*/
  74
  75 static void at91_start_clock(struct ohci_at91_priv *ohci_at91)
  76 {
  77         if (ohci_at91->clocked)
  78                 return;
  79
  80         clk_set_rate(ohci_at91->fclk, 48000000);
  81         clk_prepare_enable(ohci_at91->hclk);
  82         clk_prepare_enable(ohci_at91->iclk);
  83         clk_prepare_enable(ohci_at91->fclk);
  84         ohci_at91->clocked = true;
  85 }
  86
  87 static void at91_stop_clock(struct ohci_at91_priv *ohci_at91)
  88 {
  89         if (!ohci_at91->clocked)
  90                 return;
  91
  92         clk_disable_unprepare(ohci_at91->fclk);
  93         clk_disable_unprepare(ohci_at91->iclk);
  94         clk_disable_unprepare(ohci_at91->hclk);
  95         ohci_at91->clocked = false;
  96 }
  97
  98 static void at91_start_hc(struct platform_device *pdev)
  99 {
 100         struct usb_hcd *hcd = platform_get_drvdata(pdev);
 101         struct ohci_regs __iomem *regs = hcd->regs;
 102         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 103
 104         dev_dbg(&pdev->dev, "start\n");
 105
 106         /*
 107          * Start the USB clocks.
 108          */
 109         at91_start_clock(ohci_at91);
 110
 111         /*
 112          * The USB host controller must remain in reset.
 113          */
 114         writel(0, &regs->control);
 115 }
 116
 117 static void at91_stop_hc(struct platform_device *pdev)
 118 {
 119         struct usb_hcd *hcd = platform_get_drvdata(pdev);
 120         struct ohci_regs __iomem *regs = hcd->regs;
 121         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 122
 123         dev_dbg(&pdev->dev, "stop\n");
 124
 125         /*
 126          * Put the USB host controller into reset.
 127          */
 128         writel(0, &regs->control);
 129
 130         /*
 131          * Stop the USB clocks.
 132          */
 133         at91_stop_clock(ohci_at91);
 134 }
 135
 136
 137 /*-------------------------------------------------------------------------*/
 138
 139 static void usb_hcd_at91_remove (struct usb_hcd *, struct platform_device *);
 140
 141 static struct regmap *at91_dt_syscon_sfr(void)
 142 {
 143         struct regmap *regmap;
 144
 145         regmap = syscon_regmap_lookup_by_compatible("atmel,sama5d2-sfr");
 146         if (IS_ERR(regmap))
 147                 regmap = NULL;
 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_warn(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  * @dev: USB Host Controller being removed
 250  * Context: !in_interrupt()
 251  *
 252  * Reverses the effect of usb_hcd_at91_probe(), first invoking
 253  * the HCD's stop() method.  It is always called from a thread
 254  * context, "rmmod" or something similar.
 255  *
 256  */
 257 static void usb_hcd_at91_remove(struct usb_hcd *hcd,
 258                                 struct platform_device *pdev)
 259 {
 260         usb_remove_hcd(hcd);
 261         at91_stop_hc(pdev);
 262         usb_put_hcd(hcd);
 263 }
 264
 265 /*-------------------------------------------------------------------------*/
 266 static void ohci_at91_usb_set_power(struct at91_usbh_data *pdata, int port, int enable)
 267 {
 268         if (!valid_port(port))
 269                 return;
 270
 271         if (!gpio_is_valid(pdata->vbus_pin[port]))
 272                 return;
 273
 274         gpio_set_value(pdata->vbus_pin[port],
 275                        pdata->vbus_pin_active_low[port] ^ enable);
 276 }
 277
 278 static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
 279 {
 280         if (!valid_port(port))
 281                 return -EINVAL;
 282
 283         if (!gpio_is_valid(pdata->vbus_pin[port]))
 284                 return -EINVAL;
 285
 286         return gpio_get_value(pdata->vbus_pin[port]) ^
 287                 pdata->vbus_pin_active_low[port];
 288 }
 289
 290 /*
 291  * Update the status data from the hub with the over-current indicator change.
 292  */
 293 static int ohci_at91_hub_status_data(struct usb_hcd *hcd, char *buf)
 294 {
 295         struct at91_usbh_data *pdata = hcd->self.controller->platform_data;
 296         int length = ohci_hub_status_data(hcd, buf);
 297         int port;
 298
 299         at91_for_each_port(port) {
 300                 if (pdata->overcurrent_changed[port]) {
 301                         if (!length)
 302                                 length = 1;
 303                         buf[0] |= 1 << (port + 1);
 304                 }
 305         }
 306
 307         return length;
 308 }
 309
 310 static int ohci_at91_port_suspend(struct regmap *regmap, u8 set)
 311 {
 312         u32 regval;
 313         int ret;
 314
 315         if (!regmap)
 316                 return 0;
 317
 318         ret = regmap_read(regmap, AT91_SFR_OHCIICR, &regval);
 319         if (ret)
 320                 return ret;
 321
 322         if (set)
 323                 regval |= AT91_OHCIICR_USB_SUSPEND;
 324         else
 325                 regval &= ~AT91_OHCIICR_USB_SUSPEND;
 326
 327         regmap_write(regmap, AT91_SFR_OHCIICR, regval);
 328
 329         return 0;
 330 }
 331
 332 /*
 333  * Look at the control requests to the root hub and see if we need to override.
 334  */
 335 static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 336                                  u16 wIndex, char *buf, u16 wLength)
 337 {
 338         struct at91_usbh_data *pdata = dev_get_platdata(hcd->self.controller);
 339         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 340         struct usb_hub_descriptor *desc;
 341         int ret = -EINVAL;
 342         u32 *data = (u32 *)buf;
 343
 344         dev_dbg(hcd->self.controller,
 345                 "ohci_at91_hub_control(%p,0x%04x,0x%04x,0x%04x,%p,%04x)\n",
 346                 hcd, typeReq, wValue, wIndex, buf, wLength);
 347
 348         wIndex--;
 349
 350         switch (typeReq) {
 351         case SetPortFeature:
 352                 switch (wValue) {
 353                 case USB_PORT_FEAT_POWER:
 354                         dev_dbg(hcd->self.controller, "SetPortFeat: POWER\n");
 355                         if (valid_port(wIndex)) {
 356                                 ohci_at91_usb_set_power(pdata, wIndex, 1);
 357                                 ret = 0;
 358                         }
 359
 360                         goto out;
 361
 362                 case USB_PORT_FEAT_SUSPEND:
 363                         dev_dbg(hcd->self.controller, "SetPortFeat: SUSPEND\n");
 364                         if (valid_port(wIndex) && ohci_at91->sfr_regmap) {
 365                                 ohci_at91_port_suspend(ohci_at91->sfr_regmap,
 366                                                        1);
 367                                 return 0;
 368                         }
 369                         break;
 370                 }
 371                 break;
 372
 373         case ClearPortFeature:
 374                 switch (wValue) {
 375                 case USB_PORT_FEAT_C_OVER_CURRENT:
 376                         dev_dbg(hcd->self.controller,
 377                                 "ClearPortFeature: C_OVER_CURRENT\n");
 378
 379                         if (valid_port(wIndex)) {
 380                                 pdata->overcurrent_changed[wIndex] = 0;
 381                                 pdata->overcurrent_status[wIndex] = 0;
 382                         }
 383
 384                         goto out;
 385
 386                 case USB_PORT_FEAT_OVER_CURRENT:
 387                         dev_dbg(hcd->self.controller,
 388                                 "ClearPortFeature: OVER_CURRENT\n");
 389
 390                         if (valid_port(wIndex))
 391                                 pdata->overcurrent_status[wIndex] = 0;
 392
 393                         goto out;
 394
 395                 case USB_PORT_FEAT_POWER:
 396                         dev_dbg(hcd->self.controller,
 397                                 "ClearPortFeature: POWER\n");
 398
 399                         if (valid_port(wIndex)) {
 400                                 ohci_at91_usb_set_power(pdata, wIndex, 0);
 401                                 return 0;
 402                         }
 403                         break;
 404
 405                 case USB_PORT_FEAT_SUSPEND:
 406                         dev_dbg(hcd->self.controller, "ClearPortFeature: SUSPEND\n");
 407                         if (valid_port(wIndex) && ohci_at91->sfr_regmap) {
 408                                 ohci_at91_port_suspend(ohci_at91->sfr_regmap,
 409                                                        0);
 410                                 return 0;
 411                         }
 412                         break;
 413                 }
 414                 break;
 415         }
 416
 417         ret = ohci_hub_control(hcd, typeReq, wValue, wIndex + 1, buf, wLength);
 418         if (ret)
 419                 goto out;
 420
 421         switch (typeReq) {
 422         case GetHubDescriptor:
 423
 424                 /* update the hub's descriptor */
 425
 426                 desc = (struct usb_hub_descriptor *)buf;
 427
 428                 dev_dbg(hcd->self.controller, "wHubCharacteristics 0x%04x\n",
 429                         desc->wHubCharacteristics);
 430
 431                 /* remove the old configurations for power-switching, and
 432                  * over-current protection, and insert our new configuration
 433                  */
 434
 435                 desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_LPSM);
 436                 desc->wHubCharacteristics |=
 437                         cpu_to_le16(HUB_CHAR_INDV_PORT_LPSM);
 438
 439                 if (pdata->overcurrent_supported) {
 440                         desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_OCPM);
 441                         desc->wHubCharacteristics |=
 442                                 cpu_to_le16(HUB_CHAR_INDV_PORT_OCPM);
 443                 }
 444
 445                 dev_dbg(hcd->self.controller, "wHubCharacteristics after 0x%04x\n",
 446                         desc->wHubCharacteristics);
 447
 448                 return ret;
 449
 450         case GetPortStatus:
 451                 /* check port status */
 452
 453                 dev_dbg(hcd->self.controller, "GetPortStatus(%d)\n", wIndex);
 454
 455                 if (valid_port(wIndex)) {
 456                         if (!ohci_at91_usb_get_power(pdata, wIndex))
 457                                 *data &= ~cpu_to_le32(RH_PS_PPS);
 458
 459                         if (pdata->overcurrent_changed[wIndex])
 460                                 *data |= cpu_to_le32(RH_PS_OCIC);
 461
 462                         if (pdata->overcurrent_status[wIndex])
 463                                 *data |= cpu_to_le32(RH_PS_POCI);
 464                 }
 465         }
 466
 467  out:
 468         return ret;
 469 }
 470
 471 /*-------------------------------------------------------------------------*/
 472
 473 static irqreturn_t ohci_hcd_at91_overcurrent_irq(int irq, void *data)
 474 {
 475         struct platform_device *pdev = data;
 476         struct at91_usbh_data *pdata = dev_get_platdata(&pdev->dev);
 477         int val, gpio, port;
 478
 479         /* From the GPIO notifying the over-current situation, find
 480          * out the corresponding port */
 481         at91_for_each_port(port) {
 482                 if (gpio_is_valid(pdata->overcurrent_pin[port]) &&
 483                                 gpio_to_irq(pdata->overcurrent_pin[port]) == irq) {
 484                         gpio = pdata->overcurrent_pin[port];
 485                         break;
 486                 }
 487         }
 488
 489         if (port == AT91_MAX_USBH_PORTS) {
 490                 dev_err(& pdev->dev, "overcurrent interrupt from unknown GPIO\n");
 491                 return IRQ_HANDLED;
 492         }
 493
 494         val = gpio_get_value(gpio);
 495
 496         /* When notified of an over-current situation, disable power
 497            on the corresponding port, and mark this port in
 498            over-current. */
 499         if (!val) {
 500                 ohci_at91_usb_set_power(pdata, port, 0);
 501                 pdata->overcurrent_status[port]  = 1;
 502                 pdata->overcurrent_changed[port] = 1;
 503         }
 504
 505         dev_dbg(& pdev->dev, "overcurrent situation %s\n",
 506                 val ? "exited" : "notified");
 507
 508         return IRQ_HANDLED;
 509 }
 510
 511 static const struct of_device_id at91_ohci_dt_ids[] = {
 512         { .compatible = "atmel,at91rm9200-ohci" },
 513         { /* sentinel */ }
 514 };
 515
 516 MODULE_DEVICE_TABLE(of, at91_ohci_dt_ids);
 517
 518 /*-------------------------------------------------------------------------*/
 519
 520 static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
 521 {
 522         struct device_node *np = pdev->dev.of_node;
 523         struct at91_usbh_data   *pdata;
 524         int                     i;
 525         int                     gpio;
 526         int                     ret;
 527         enum of_gpio_flags      flags;
 528         u32                     ports;
 529
 530         /* Right now device-tree probed devices don't get dma_mask set.
 531          * Since shared usb code relies on it, set it here for now.
 532          * Once we have dma capability bindings this can go away.
 533          */
 534         ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 535         if (ret)
 536                 return ret;
 537
 538         pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 539         if (!pdata)
 540                 return -ENOMEM;
 541
 542         pdev->dev.platform_data = pdata;
 543
 544         if (!of_property_read_u32(np, "num-ports", &ports))
 545                 pdata->ports = ports;
 546
 547         at91_for_each_port(i) {
 548                 /*
 549                  * do not configure PIO if not in relation with
 550                  * real USB port on board
 551                  */
 552                 if (i >= pdata->ports) {
 553                         pdata->vbus_pin[i] = -EINVAL;
 554                         pdata->overcurrent_pin[i] = -EINVAL;
 555                         continue;
 556                 }
 557
 558                 gpio = of_get_named_gpio_flags(np, "atmel,vbus-gpio", i,
 559                                                &flags);
 560                 pdata->vbus_pin[i] = gpio;
 561                 if (!gpio_is_valid(gpio))
 562                         continue;
 563                 pdata->vbus_pin_active_low[i] = flags & OF_GPIO_ACTIVE_LOW;
 564
 565                 ret = gpio_request(gpio, "ohci_vbus");
 566                 if (ret) {
 567                         dev_err(&pdev->dev,
 568                                 "can't request vbus gpio %d\n", gpio);
 569                         continue;
 570                 }
 571                 ret = gpio_direction_output(gpio,
 572                                         !pdata->vbus_pin_active_low[i]);
 573                 if (ret) {
 574                         dev_err(&pdev->dev,
 575                                 "can't put vbus gpio %d as output %d\n",
 576                                 gpio, !pdata->vbus_pin_active_low[i]);
 577                         gpio_free(gpio);
 578                         continue;
 579                 }
 580
 581                 ohci_at91_usb_set_power(pdata, i, 1);
 582         }
 583
 584         at91_for_each_port(i) {
 585                 if (i >= pdata->ports)
 586                         break;
 587
 588                 pdata->overcurrent_pin[i] =
 589                         of_get_named_gpio_flags(np, "atmel,oc-gpio", i, &flags);
 590
 591                 if (!gpio_is_valid(pdata->overcurrent_pin[i]))
 592                         continue;
 593                 gpio = pdata->overcurrent_pin[i];
 594
 595                 ret = gpio_request(gpio, "ohci_overcurrent");
 596                 if (ret) {
 597                         dev_err(&pdev->dev,
 598                                 "can't request overcurrent gpio %d\n",
 599                                 gpio);
 600                         continue;
 601                 }
 602
 603                 ret = gpio_direction_input(gpio);
 604                 if (ret) {
 605                         dev_err(&pdev->dev,
 606                                 "can't configure overcurrent gpio %d as input\n",
 607                                 gpio);
 608                         gpio_free(gpio);
 609                         continue;
 610                 }
 611
 612                 ret = request_irq(gpio_to_irq(gpio),
 613                                   ohci_hcd_at91_overcurrent_irq,
 614                                   IRQF_SHARED, "ohci_overcurrent", pdev);
 615                 if (ret) {
 616                         gpio_free(gpio);
 617                         dev_err(&pdev->dev,
 618                                 "can't get gpio IRQ for overcurrent\n");
 619                 }
 620         }
 621
 622         device_init_wakeup(&pdev->dev, 1);
 623         return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
 624 }
 625
 626 static int ohci_hcd_at91_drv_remove(struct platform_device *pdev)
 627 {
 628         struct at91_usbh_data   *pdata = dev_get_platdata(&pdev->dev);
 629         int                     i;
 630
 631         if (pdata) {
 632                 at91_for_each_port(i) {
 633                         if (!gpio_is_valid(pdata->vbus_pin[i]))
 634                                 continue;
 635                         ohci_at91_usb_set_power(pdata, i, 0);
 636                         gpio_free(pdata->vbus_pin[i]);
 637                 }
 638
 639                 at91_for_each_port(i) {
 640                         if (!gpio_is_valid(pdata->overcurrent_pin[i]))
 641                                 continue;
 642                         free_irq(gpio_to_irq(pdata->overcurrent_pin[i]), pdev);
 643                         gpio_free(pdata->overcurrent_pin[i]);
 644                 }
 645         }
 646
 647         device_init_wakeup(&pdev->dev, 0);
 648         usb_hcd_at91_remove(platform_get_drvdata(pdev), pdev);
 649         return 0;
 650 }
 651
 652 static int __maybe_unused
 653 ohci_hcd_at91_drv_suspend(struct device *dev)
 654 {
 655         struct usb_hcd  *hcd = dev_get_drvdata(dev);
 656         struct ohci_hcd *ohci = hcd_to_ohci(hcd);
 657         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 658         int             ret;
 659
 660         /*
 661          * Disable wakeup if we are going to sleep with slow clock mode
 662          * enabled.
 663          */
 664         ohci_at91->wakeup = device_may_wakeup(dev)
 665                         && !at91_suspend_entering_slow_clock();
 666
 667         if (ohci_at91->wakeup)
 668                 enable_irq_wake(hcd->irq);
 669
 670         ohci_at91_port_suspend(ohci_at91->sfr_regmap, 1);
 671
 672         ret = ohci_suspend(hcd, ohci_at91->wakeup);
 673         if (ret) {
 674                 if (ohci_at91->wakeup)
 675                         disable_irq_wake(hcd->irq);
 676                 return ret;
 677         }
 678         /*
 679          * The integrated transceivers seem unable to notice disconnect,
 680          * reconnect, or wakeup without the 48 MHz clock active.  so for
 681          * correctness, always discard connection state (using reset).
 682          *
 683          * REVISIT: some boards will be able to turn VBUS off...
 684          */
 685         if (!ohci_at91->wakeup) {
 686                 ohci->rh_state = OHCI_RH_HALTED;
 687
 688                 /* flush the writes */
 689                 (void) ohci_readl (ohci, &ohci->regs->control);
 690                 at91_stop_clock(ohci_at91);
 691         }
 692
 693         return ret;
 694 }
 695
 696 static int __maybe_unused
 697 ohci_hcd_at91_drv_resume(struct device *dev)
 698 {
 699         struct usb_hcd  *hcd = dev_get_drvdata(dev);
 700         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 701
 702         if (ohci_at91->wakeup)
 703                 disable_irq_wake(hcd->irq);
 704
 705         at91_start_clock(ohci_at91);
 706
 707         ohci_resume(hcd, false);
 708
 709         ohci_at91_port_suspend(ohci_at91->sfr_regmap, 0);
 710
 711         return 0;
 712 }
 713
 714 static SIMPLE_DEV_PM_OPS(ohci_hcd_at91_pm_ops, ohci_hcd_at91_drv_suspend,
 715                                         ohci_hcd_at91_drv_resume);
 716
 717 static struct platform_driver ohci_hcd_at91_driver = {
 718         .probe          = ohci_hcd_at91_drv_probe,
 719         .remove         = ohci_hcd_at91_drv_remove,
 720         .shutdown       = usb_hcd_platform_shutdown,
 721         .driver         = {
 722                 .name   = "at91_ohci",
 723                 .pm     = &ohci_hcd_at91_pm_ops,
 724                 .of_match_table = at91_ohci_dt_ids,
 725         },
 726 };
 727
 728 static int __init ohci_at91_init(void)
 729 {
 730         if (usb_disabled())
 731                 return -ENODEV;
 732
 733         pr_info("%s: " DRIVER_DESC "\n", hcd_name);
 734         ohci_init_driver(&ohci_at91_hc_driver, &ohci_at91_drv_overrides);
 735
 736         /*
 737          * The Atmel HW has some unusual quirks, which require Atmel-specific
 738          * workarounds. We override certain hc_driver functions here to
 739          * achieve that. We explicitly do not enhance ohci_driver_overrides to
 740          * allow this more easily, since this is an unusual case, and we don't
 741          * want to encourage others to override these functions by making it
 742          * too easy.
 743          */
 744
 745         ohci_at91_hc_driver.hub_status_data     = ohci_at91_hub_status_data;
 746         ohci_at91_hc_driver.hub_control         = ohci_at91_hub_control;
 747
 748         return platform_driver_register(&ohci_hcd_at91_driver);
 749 }
 750 module_init(ohci_at91_init);
 751
 752 static void __exit ohci_at91_cleanup(void)
 753 {
 754         platform_driver_unregister(&ohci_hcd_at91_driver);
 755 }
 756 module_exit(ohci_at91_cleanup);
 757
 758 MODULE_DESCRIPTION(DRIVER_DESC);
 759 MODULE_LICENSE("GPL");
 760 MODULE_ALIAS("platform:at91_ohci");