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/arm-smccc.h>
  17 #include <linux/clk.h>
  18 #include <linux/dma-mapping.h>
  19 #include <linux/gpio/consumer.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/of.h>
  27 #include <linux/regmap.h>
  28 #include <linux/usb.h>
  29 #include <linux/usb/hcd.h>
  30 #include <soc/at91/atmel-sfr.h>
  31
  32 #include "ohci.h"
  33
  34 #define valid_port(index)       ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS)
  35 #define at91_for_each_port(index)       \
  36                 for ((index) = 0; (index) < AT91_MAX_USBH_PORTS; (index)++)
  37
  38 /* interface, function and usb clocks; sometimes also an AHB clock */
  39 #define hcd_to_ohci_at91_priv(h) \
  40         ((struct ohci_at91_priv *)hcd_to_ohci(h)->priv)
  41
  42 #define AT91_MAX_USBH_PORTS     3
  43 struct at91_usbh_data {
  44         struct gpio_desc *vbus_pin[AT91_MAX_USBH_PORTS];
  45         struct gpio_desc *overcurrent_pin[AT91_MAX_USBH_PORTS];
  46         u8 ports;                               /* number of ports on root hub */
  47         u8 overcurrent_supported;
  48         u8 overcurrent_status[AT91_MAX_USBH_PORTS];
  49         u8 overcurrent_changed[AT91_MAX_USBH_PORTS];
  50 };
  51
  52 struct ohci_at91_priv {
  53         struct clk *iclk;
  54         struct clk *fclk;
  55         struct clk *hclk;
  56         bool clocked;
  57         bool wakeup;            /* Saved wake-up state for resume */
  58         struct regmap *sfr_regmap;
  59         u32 suspend_smc_id;
  60 };
  61 /* interface and function clocks; sometimes also an AHB clock */
  62
  63 #define DRIVER_DESC "OHCI Atmel driver"
  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 u32 at91_dt_suspend_smc(struct device *dev)
 139 {
 140         u32 suspend_smc_id;
 141
 142         if (!dev->of_node)
 143                 return 0;
 144
 145         if (of_property_read_u32(dev->of_node, "microchip,suspend-smc-id", &suspend_smc_id))
 146                 return 0;
 147
 148         return suspend_smc_id;
 149 }
 150
 151 static struct regmap *at91_dt_syscon_sfr(void)
 152 {
 153         struct regmap *regmap;
 154
 155         regmap = syscon_regmap_lookup_by_compatible("atmel,sama5d2-sfr");
 156         if (IS_ERR(regmap)) {
 157                 regmap = syscon_regmap_lookup_by_compatible("microchip,sam9x60-sfr");
 158                 if (IS_ERR(regmap))
 159                         regmap = NULL;
 160         }
 161
 162         return regmap;
 163 }
 164
 165 /* configure so an HC device and id are always provided */
 166 /* always called with process context; sleeping is OK */
 167
 168
 169 /*
 170  * usb_hcd_at91_probe - initialize AT91-based HCDs
 171  * @driver:     Pointer to hc driver instance
 172  * @pdev:       USB controller to probe
 173  *
 174  * Context: task context, might sleep
 175  *
 176  * Allocates basic resources for this USB host controller, and
 177  * then invokes the start() method for the HCD associated with it
 178  * through the hotplug entry's driver_data.
 179  */
 180 static int usb_hcd_at91_probe(const struct hc_driver *driver,
 181                         struct platform_device *pdev)
 182 {
 183         struct at91_usbh_data *board;
 184         struct ohci_hcd *ohci;
 185         int retval;
 186         struct usb_hcd *hcd;
 187         struct ohci_at91_priv *ohci_at91;
 188         struct device *dev = &pdev->dev;
 189         struct resource *res;
 190         int irq;
 191
 192         irq = platform_get_irq(pdev, 0);
 193         if (irq < 0)
 194                 return irq;
 195
 196         hcd = usb_create_hcd(driver, dev, "at91");
 197         if (!hcd)
 198                 return -ENOMEM;
 199         ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 200
 201         hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 202         if (IS_ERR(hcd->regs)) {
 203                 retval = PTR_ERR(hcd->regs);
 204                 goto err;
 205         }
 206         hcd->rsrc_start = res->start;
 207         hcd->rsrc_len = resource_size(res);
 208
 209         ohci_at91->iclk = devm_clk_get(dev, "ohci_clk");
 210         if (IS_ERR(ohci_at91->iclk)) {
 211                 dev_err(dev, "failed to get ohci_clk\n");
 212                 retval = PTR_ERR(ohci_at91->iclk);
 213                 goto err;
 214         }
 215         ohci_at91->fclk = devm_clk_get(dev, "uhpck");
 216         if (IS_ERR(ohci_at91->fclk)) {
 217                 dev_err(dev, "failed to get uhpck\n");
 218                 retval = PTR_ERR(ohci_at91->fclk);
 219                 goto err;
 220         }
 221         ohci_at91->hclk = devm_clk_get(dev, "hclk");
 222         if (IS_ERR(ohci_at91->hclk)) {
 223                 dev_err(dev, "failed to get hclk\n");
 224                 retval = PTR_ERR(ohci_at91->hclk);
 225                 goto err;
 226         }
 227
 228         ohci_at91->suspend_smc_id = at91_dt_suspend_smc(dev);
 229         if (!ohci_at91->suspend_smc_id)  {
 230                 dev_dbg(dev, "failed to find sfr suspend smc id, using regmap\n");
 231                 ohci_at91->sfr_regmap = at91_dt_syscon_sfr();
 232                 if (!ohci_at91->sfr_regmap)
 233                         dev_dbg(dev, "failed to find sfr node\n");
 234         }
 235
 236         board = hcd->self.controller->platform_data;
 237         ohci = hcd_to_ohci(hcd);
 238         ohci->num_ports = board->ports;
 239         at91_start_hc(pdev);
 240
 241         /*
 242          * The RemoteWakeupConnected bit has to be set explicitly
 243          * before calling ohci_run. The reset value of this bit is 0.
 244          */
 245         ohci->hc_control = OHCI_CTRL_RWC;
 246
 247         retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
 248         if (retval == 0) {
 249                 device_wakeup_enable(hcd->self.controller);
 250                 return retval;
 251         }
 252
 253         /* Error handling */
 254         at91_stop_hc(pdev);
 255
 256  err:
 257         usb_put_hcd(hcd);
 258         return retval;
 259 }
 260
 261
 262 /* may be called with controller, bus, and devices active */
 263
 264 /*
 265  * usb_hcd_at91_remove - shutdown processing for AT91-based HCDs
 266  * @hcd:        USB controller to remove
 267  * @pdev:       Platform device required for cleanup
 268  *
 269  * Context: task context, might sleep
 270  *
 271  * Reverses the effect of usb_hcd_at91_probe(), first invoking
 272  * the HCD's stop() method.  It is always called from a thread
 273  * context, "rmmod" or something similar.
 274  */
 275 static void usb_hcd_at91_remove(struct usb_hcd *hcd,
 276                                 struct platform_device *pdev)
 277 {
 278         usb_remove_hcd(hcd);
 279         at91_stop_hc(pdev);
 280         usb_put_hcd(hcd);
 281 }
 282
 283 /*-------------------------------------------------------------------------*/
 284 static void ohci_at91_usb_set_power(struct at91_usbh_data *pdata, int port, int enable)
 285 {
 286         if (!valid_port(port))
 287                 return;
 288
 289         gpiod_set_value(pdata->vbus_pin[port], enable);
 290 }
 291
 292 static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
 293 {
 294         if (!valid_port(port))
 295                 return -EINVAL;
 296
 297         return gpiod_get_value(pdata->vbus_pin[port]);
 298 }
 299
 300 /*
 301  * Update the status data from the hub with the over-current indicator change.
 302  */
 303 static int ohci_at91_hub_status_data(struct usb_hcd *hcd, char *buf)
 304 {
 305         struct at91_usbh_data *pdata = hcd->self.controller->platform_data;
 306         int length = ohci_hub_status_data(hcd, buf);
 307         int port;
 308
 309         at91_for_each_port(port) {
 310                 if (pdata->overcurrent_changed[port]) {
 311                         if (!length)
 312                                 length = 1;
 313                         buf[0] |= 1 << (port + 1);
 314                 }
 315         }
 316
 317         return length;
 318 }
 319
 320 static int ohci_at91_port_suspend(struct ohci_at91_priv *ohci_at91, u8 set)
 321 {
 322         struct regmap *regmap = ohci_at91->sfr_regmap;
 323         u32 regval;
 324         int ret;
 325
 326         if (ohci_at91->suspend_smc_id) {
 327                 struct arm_smccc_res res;
 328
 329                 arm_smccc_smc(ohci_at91->suspend_smc_id, set, 0, 0, 0, 0, 0, 0, &res);
 330                 if (res.a0)
 331                         return -EINVAL;
 332         } else if (regmap) {
 333                 ret = regmap_read(regmap, AT91_SFR_OHCIICR, &regval);
 334                 if (ret)
 335                         return ret;
 336
 337                 if (set)
 338                         regval |= AT91_OHCIICR_USB_SUSPEND;
 339                 else
 340                         regval &= ~AT91_OHCIICR_USB_SUSPEND;
 341
 342                 regmap_write(regmap, AT91_SFR_OHCIICR, regval);
 343         }
 344
 345         return 0;
 346 }
 347
 348 /*
 349  * Look at the control requests to the root hub and see if we need to override.
 350  */
 351 static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 352                                  u16 wIndex, char *buf, u16 wLength)
 353 {
 354         struct at91_usbh_data *pdata = dev_get_platdata(hcd->self.controller);
 355         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 356         struct usb_hub_descriptor *desc;
 357         int ret = -EINVAL;
 358         u32 *data = (u32 *)buf;
 359
 360         dev_dbg(hcd->self.controller,
 361                 "ohci_at91_hub_control(%p,0x%04x,0x%04x,0x%04x,%p,%04x)\n",
 362                 hcd, typeReq, wValue, wIndex, buf, wLength);
 363
 364         wIndex--;
 365
 366         switch (typeReq) {
 367         case SetPortFeature:
 368                 switch (wValue) {
 369                 case USB_PORT_FEAT_POWER:
 370                         dev_dbg(hcd->self.controller, "SetPortFeat: POWER\n");
 371                         if (valid_port(wIndex)) {
 372                                 ohci_at91_usb_set_power(pdata, wIndex, 1);
 373                                 ret = 0;
 374                         }
 375
 376                         goto out;
 377
 378                 case USB_PORT_FEAT_SUSPEND:
 379                         dev_dbg(hcd->self.controller, "SetPortFeat: SUSPEND\n");
 380                         if (valid_port(wIndex)) {
 381                                 ohci_at91_port_suspend(ohci_at91, 1);
 382                                 return 0;
 383                         }
 384                         break;
 385                 }
 386                 break;
 387
 388         case ClearPortFeature:
 389                 switch (wValue) {
 390                 case USB_PORT_FEAT_C_OVER_CURRENT:
 391                         dev_dbg(hcd->self.controller,
 392                                 "ClearPortFeature: C_OVER_CURRENT\n");
 393
 394                         if (valid_port(wIndex)) {
 395                                 pdata->overcurrent_changed[wIndex] = 0;
 396                                 pdata->overcurrent_status[wIndex] = 0;
 397                         }
 398
 399                         goto out;
 400
 401                 case USB_PORT_FEAT_OVER_CURRENT:
 402                         dev_dbg(hcd->self.controller,
 403                                 "ClearPortFeature: OVER_CURRENT\n");
 404
 405                         if (valid_port(wIndex))
 406                                 pdata->overcurrent_status[wIndex] = 0;
 407
 408                         goto out;
 409
 410                 case USB_PORT_FEAT_POWER:
 411                         dev_dbg(hcd->self.controller,
 412                                 "ClearPortFeature: POWER\n");
 413
 414                         if (valid_port(wIndex)) {
 415                                 ohci_at91_usb_set_power(pdata, wIndex, 0);
 416                                 return 0;
 417                         }
 418                         break;
 419
 420                 case USB_PORT_FEAT_SUSPEND:
 421                         dev_dbg(hcd->self.controller, "ClearPortFeature: SUSPEND\n");
 422                         if (valid_port(wIndex)) {
 423                                 ohci_at91_port_suspend(ohci_at91, 0);
 424                                 return 0;
 425                         }
 426                         break;
 427                 }
 428                 break;
 429         }
 430
 431         ret = ohci_hub_control(hcd, typeReq, wValue, wIndex + 1, buf, wLength);
 432         if (ret)
 433                 goto out;
 434
 435         switch (typeReq) {
 436         case GetHubDescriptor:
 437
 438                 /* update the hub's descriptor */
 439
 440                 desc = (struct usb_hub_descriptor *)buf;
 441
 442                 dev_dbg(hcd->self.controller, "wHubCharacteristics 0x%04x\n",
 443                         desc->wHubCharacteristics);
 444
 445                 /* remove the old configurations for power-switching, and
 446                  * over-current protection, and insert our new configuration
 447                  */
 448
 449                 desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_LPSM);
 450                 desc->wHubCharacteristics |=
 451                         cpu_to_le16(HUB_CHAR_INDV_PORT_LPSM);
 452
 453                 if (pdata->overcurrent_supported) {
 454                         desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_OCPM);
 455                         desc->wHubCharacteristics |=
 456                                 cpu_to_le16(HUB_CHAR_INDV_PORT_OCPM);
 457                 }
 458
 459                 dev_dbg(hcd->self.controller, "wHubCharacteristics after 0x%04x\n",
 460                         desc->wHubCharacteristics);
 461
 462                 return ret;
 463
 464         case GetPortStatus:
 465                 /* check port status */
 466
 467                 dev_dbg(hcd->self.controller, "GetPortStatus(%d)\n", wIndex);
 468
 469                 if (valid_port(wIndex)) {
 470                         if (!ohci_at91_usb_get_power(pdata, wIndex))
 471                                 *data &= ~cpu_to_le32(RH_PS_PPS);
 472
 473                         if (pdata->overcurrent_changed[wIndex])
 474                                 *data |= cpu_to_le32(RH_PS_OCIC);
 475
 476                         if (pdata->overcurrent_status[wIndex])
 477                                 *data |= cpu_to_le32(RH_PS_POCI);
 478                 }
 479         }
 480
 481  out:
 482         return ret;
 483 }
 484
 485 /*-------------------------------------------------------------------------*/
 486
 487 static irqreturn_t ohci_hcd_at91_overcurrent_irq(int irq, void *data)
 488 {
 489         struct platform_device *pdev = data;
 490         struct at91_usbh_data *pdata = dev_get_platdata(&pdev->dev);
 491         int val, port;
 492
 493         /* From the GPIO notifying the over-current situation, find
 494          * out the corresponding port */
 495         at91_for_each_port(port) {
 496                 if (gpiod_to_irq(pdata->overcurrent_pin[port]) == irq)
 497                         break;
 498         }
 499
 500         if (port == AT91_MAX_USBH_PORTS) {
 501                 dev_err(& pdev->dev, "overcurrent interrupt from unknown GPIO\n");
 502                 return IRQ_HANDLED;
 503         }
 504
 505         val = gpiod_get_value(pdata->overcurrent_pin[port]);
 506
 507         /* When notified of an over-current situation, disable power
 508            on the corresponding port, and mark this port in
 509            over-current. */
 510         if (!val) {
 511                 ohci_at91_usb_set_power(pdata, port, 0);
 512                 pdata->overcurrent_status[port]  = 1;
 513                 pdata->overcurrent_changed[port] = 1;
 514         }
 515
 516         dev_dbg(& pdev->dev, "overcurrent situation %s\n",
 517                 val ? "exited" : "notified");
 518
 519         return IRQ_HANDLED;
 520 }
 521
 522 static const struct of_device_id at91_ohci_dt_ids[] = {
 523         { .compatible = "atmel,at91rm9200-ohci" },
 524         { /* sentinel */ }
 525 };
 526
 527 MODULE_DEVICE_TABLE(of, at91_ohci_dt_ids);
 528
 529 /*-------------------------------------------------------------------------*/
 530
 531 static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
 532 {
 533         struct device_node *np = pdev->dev.of_node;
 534         struct at91_usbh_data   *pdata;
 535         int                     i;
 536         int                     ret;
 537         int                     err;
 538         u32                     ports;
 539
 540         /* Right now device-tree probed devices don't get dma_mask set.
 541          * Since shared usb code relies on it, set it here for now.
 542          * Once we have dma capability bindings this can go away.
 543          */
 544         ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 545         if (ret)
 546                 return ret;
 547
 548         pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 549         if (!pdata)
 550                 return -ENOMEM;
 551
 552         pdev->dev.platform_data = pdata;
 553
 554         if (!of_property_read_u32(np, "num-ports", &ports))
 555                 pdata->ports = ports;
 556
 557         at91_for_each_port(i) {
 558                 if (i >= pdata->ports)
 559                         break;
 560
 561                 pdata->vbus_pin[i] =
 562                         devm_gpiod_get_index_optional(&pdev->dev, "atmel,vbus",
 563                                                       i, GPIOD_OUT_HIGH);
 564                 if (IS_ERR(pdata->vbus_pin[i])) {
 565                         err = PTR_ERR(pdata->vbus_pin[i]);
 566                         dev_err(&pdev->dev, "unable to claim gpio \"vbus\": %d\n", err);
 567                         continue;
 568                 }
 569         }
 570
 571         at91_for_each_port(i) {
 572                 if (i >= pdata->ports)
 573                         break;
 574
 575                 pdata->overcurrent_pin[i] =
 576                         devm_gpiod_get_index_optional(&pdev->dev, "atmel,oc",
 577                                                       i, GPIOD_IN);
 578                 if (!pdata->overcurrent_pin[i])
 579                         continue;
 580                 if (IS_ERR(pdata->overcurrent_pin[i])) {
 581                         err = PTR_ERR(pdata->overcurrent_pin[i]);
 582                         dev_err(&pdev->dev, "unable to claim gpio \"overcurrent\": %d\n", err);
 583                         continue;
 584                 }
 585
 586                 ret = devm_request_irq(&pdev->dev,
 587                                        gpiod_to_irq(pdata->overcurrent_pin[i]),
 588                                        ohci_hcd_at91_overcurrent_irq,
 589                                        IRQF_SHARED,
 590                                        "ohci_overcurrent", pdev);
 591                 if (ret)
 592                         dev_info(&pdev->dev, "failed to request gpio \"overcurrent\" IRQ\n");
 593         }
 594
 595         device_init_wakeup(&pdev->dev, 1);
 596         return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
 597 }
 598
 599 static void ohci_hcd_at91_drv_remove(struct platform_device *pdev)
 600 {
 601         struct at91_usbh_data   *pdata = dev_get_platdata(&pdev->dev);
 602         int                     i;
 603
 604         if (pdata) {
 605                 at91_for_each_port(i)
 606                         ohci_at91_usb_set_power(pdata, i, 0);
 607         }
 608
 609         device_init_wakeup(&pdev->dev, 0);
 610         usb_hcd_at91_remove(platform_get_drvdata(pdev), pdev);
 611 }
 612
 613 static int __maybe_unused
 614 ohci_hcd_at91_drv_suspend(struct device *dev)
 615 {
 616         struct usb_hcd  *hcd = dev_get_drvdata(dev);
 617         struct ohci_hcd *ohci = hcd_to_ohci(hcd);
 618         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 619         int             ret;
 620
 621         /*
 622          * Disable wakeup if we are going to sleep with slow clock mode
 623          * enabled.
 624          */
 625         ohci_at91->wakeup = device_may_wakeup(dev)
 626                         && !at91_suspend_entering_slow_clock();
 627
 628         if (ohci_at91->wakeup)
 629                 enable_irq_wake(hcd->irq);
 630
 631         ret = ohci_suspend(hcd, ohci_at91->wakeup);
 632         if (ret) {
 633                 if (ohci_at91->wakeup)
 634                         disable_irq_wake(hcd->irq);
 635                 return ret;
 636         }
 637         /*
 638          * The integrated transceivers seem unable to notice disconnect,
 639          * reconnect, or wakeup without the 48 MHz clock active.  so for
 640          * correctness, always discard connection state (using reset).
 641          *
 642          * REVISIT: some boards will be able to turn VBUS off...
 643          */
 644         if (!ohci_at91->wakeup) {
 645                 ohci->rh_state = OHCI_RH_HALTED;
 646
 647                 /* flush the writes */
 648                 (void) ohci_readl (ohci, &ohci->regs->control);
 649                 msleep(1);
 650                 ohci_at91_port_suspend(ohci_at91, 1);
 651                 at91_stop_clock(ohci_at91);
 652         } else {
 653                 ohci_at91_port_suspend(ohci_at91, 1);
 654         }
 655
 656         return ret;
 657 }
 658
 659 static int __maybe_unused
 660 ohci_hcd_at91_drv_resume(struct device *dev)
 661 {
 662         struct usb_hcd  *hcd = dev_get_drvdata(dev);
 663         struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
 664
 665         ohci_at91_port_suspend(ohci_at91, 0);
 666
 667         if (ohci_at91->wakeup)
 668                 disable_irq_wake(hcd->irq);
 669         else
 670                 at91_start_clock(ohci_at91);
 671
 672         /*
 673          * According to the comment in ohci_hcd_at91_drv_suspend()
 674          * we need to do a reset if the 48Mhz clock was stopped,
 675          * that is, if ohci_at91->wakeup is clear. Tell ohci_resume()
 676          * to reset in this case by setting its "hibernated" flag.
 677          */
 678         ohci_resume(hcd, !ohci_at91->wakeup);
 679
 680         return 0;
 681 }
 682
 683 static SIMPLE_DEV_PM_OPS(ohci_hcd_at91_pm_ops, ohci_hcd_at91_drv_suspend,
 684                                         ohci_hcd_at91_drv_resume);
 685
 686 static struct platform_driver ohci_hcd_at91_driver = {
 687         .probe          = ohci_hcd_at91_drv_probe,
 688         .remove_new     = ohci_hcd_at91_drv_remove,
 689         .shutdown       = usb_hcd_platform_shutdown,
 690         .driver         = {
 691                 .name   = "at91_ohci",
 692                 .pm     = &ohci_hcd_at91_pm_ops,
 693                 .of_match_table = at91_ohci_dt_ids,
 694         },
 695 };
 696
 697 static int __init ohci_at91_init(void)
 698 {
 699         if (usb_disabled())
 700                 return -ENODEV;
 701
 702         ohci_init_driver(&ohci_at91_hc_driver, &ohci_at91_drv_overrides);
 703
 704         /*
 705          * The Atmel HW has some unusual quirks, which require Atmel-specific
 706          * workarounds. We override certain hc_driver functions here to
 707          * achieve that. We explicitly do not enhance ohci_driver_overrides to
 708          * allow this more easily, since this is an unusual case, and we don't
 709          * want to encourage others to override these functions by making it
 710          * too easy.
 711          */
 712
 713         ohci_at91_hc_driver.hub_status_data     = ohci_at91_hub_status_data;
 714         ohci_at91_hc_driver.hub_control         = ohci_at91_hub_control;
 715
 716         return platform_driver_register(&ohci_hcd_at91_driver);
 717 }
 718 module_init(ohci_at91_init);
 719
 720 static void __exit ohci_at91_cleanup(void)
 721 {
 722         platform_driver_unregister(&ohci_hcd_at91_driver);
 723 }
 724 module_exit(ohci_at91_cleanup);
 725
 726 MODULE_DESCRIPTION(DRIVER_DESC);
 727 MODULE_LICENSE("GPL");
 728 MODULE_ALIAS("platform:at91_ohci");