drivers/usb/host/ohci-hub.c

   1 /*
   2  * OHCI HCD (Host Controller Driver) for USB.
   3  *
   4  * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
   5  * (C) Copyright 2000-2004 David Brownell <dbrownell@users.sourceforge.net>
   6  *
   7  * This file is licenced under GPL
   8  */
   9
  10 /*-------------------------------------------------------------------------*/
  11
  12 /*
  13  * OHCI Root Hub ... the nonsharable stuff
  14  */
  15
  16 #define dbg_port(hc,label,num,value) \
  17         ohci_dbg (hc, \
  18                 "%s roothub.portstatus [%d] " \
  19                 "= 0x%08x%s%s%s%s%s%s%s%s%s%s%s%s\n", \
  20                 label, num, temp, \
  21                 (temp & RH_PS_PRSC) ? " PRSC" : "", \
  22                 (temp & RH_PS_OCIC) ? " OCIC" : "", \
  23                 (temp & RH_PS_PSSC) ? " PSSC" : "", \
  24                 (temp & RH_PS_PESC) ? " PESC" : "", \
  25                 (temp & RH_PS_CSC) ? " CSC" : "", \
  26                 \
  27                 (temp & RH_PS_LSDA) ? " LSDA" : "", \
  28                 (temp & RH_PS_PPS) ? " PPS" : "", \
  29                 (temp & RH_PS_PRS) ? " PRS" : "", \
  30                 (temp & RH_PS_POCI) ? " POCI" : "", \
  31                 (temp & RH_PS_PSS) ? " PSS" : "", \
  32                 \
  33                 (temp & RH_PS_PES) ? " PES" : "", \
  34                 (temp & RH_PS_CCS) ? " CCS" : "" \
  35                 );
  36
  37 /*-------------------------------------------------------------------------*/
  38
  39 #define OHCI_SCHED_ENABLES \
  40         (OHCI_CTRL_CLE|OHCI_CTRL_BLE|OHCI_CTRL_PLE|OHCI_CTRL_IE)
  41
  42 static void update_done_list(struct ohci_hcd *);
  43 static void process_done_list(struct ohci_hcd *);
  44 static void finish_unlinks (struct ohci_hcd *, u16);
  45
  46 #ifdef  CONFIG_PM
  47 static int ohci_rh_suspend (struct ohci_hcd *ohci, int autostop)
  48 __releases(ohci->lock)
  49 __acquires(ohci->lock)
  50 {
  51         int                     status = 0;
  52
  53         ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
  54         switch (ohci->hc_control & OHCI_CTRL_HCFS) {
  55         case OHCI_USB_RESUME:
  56                 ohci_dbg (ohci, "resume/suspend?\n");
  57                 ohci->hc_control &= ~OHCI_CTRL_HCFS;
  58                 ohci->hc_control |= OHCI_USB_RESET;
  59                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
  60                 (void) ohci_readl (ohci, &ohci->regs->control);
  61                 /* FALL THROUGH */
  62         case OHCI_USB_RESET:
  63                 status = -EBUSY;
  64                 ohci_dbg (ohci, "needs reinit!\n");
  65                 goto done;
  66         case OHCI_USB_SUSPEND:
  67                 if (!ohci->autostop) {
  68                         ohci_dbg (ohci, "already suspended\n");
  69                         goto done;
  70                 }
  71         }
  72         ohci_dbg (ohci, "%s root hub\n",
  73                         autostop ? "auto-stop" : "suspend");
  74
  75         /* First stop any processing */
  76         if (!autostop && (ohci->hc_control & OHCI_SCHED_ENABLES)) {
  77                 ohci->hc_control &= ~OHCI_SCHED_ENABLES;
  78                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
  79                 ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
  80                 ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrstatus);
  81
  82                 /* sched disables take effect on the next frame,
  83                  * then the last WDH could take 6+ msec
  84                  */
  85                 ohci_dbg (ohci, "stopping schedules ...\n");
  86                 ohci->autostop = 0;
  87                 spin_unlock_irq (&ohci->lock);
  88                 msleep (8);
  89                 spin_lock_irq (&ohci->lock);
  90         }
  91         update_done_list(ohci);
  92         process_done_list(ohci);
  93         finish_unlinks (ohci, ohci_frame_no(ohci));
  94
  95         /*
  96          * Some controllers don't handle "global" suspend properly if
  97          * there are unsuspended ports.  For these controllers, put all
  98          * the enabled ports into suspend before suspending the root hub.
  99          */
 100         if (ohci->flags & OHCI_QUIRK_GLOBAL_SUSPEND) {
 101                 __hc32 __iomem  *portstat = ohci->regs->roothub.portstatus;
 102                 int             i;
 103                 unsigned        temp;
 104
 105                 for (i = 0; i < ohci->num_ports; (++i, ++portstat)) {
 106                         temp = ohci_readl(ohci, portstat);
 107                         if ((temp & (RH_PS_PES | RH_PS_PSS)) ==
 108                                         RH_PS_PES)
 109                                 ohci_writel(ohci, RH_PS_PSS, portstat);
 110                 }
 111         }
 112
 113         /* maybe resume can wake root hub */
 114         if (ohci_to_hcd(ohci)->self.root_hub->do_remote_wakeup || autostop) {
 115                 ohci->hc_control |= OHCI_CTRL_RWE;
 116         } else {
 117                 ohci_writel(ohci, OHCI_INTR_RHSC | OHCI_INTR_RD,
 118                                 &ohci->regs->intrdisable);
 119                 ohci->hc_control &= ~OHCI_CTRL_RWE;
 120         }
 121
 122         /* Suspend hub ... this is the "global (to this bus) suspend" mode,
 123          * which doesn't imply ports will first be individually suspended.
 124          */
 125         ohci->hc_control &= ~OHCI_CTRL_HCFS;
 126         ohci->hc_control |= OHCI_USB_SUSPEND;
 127         ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
 128         (void) ohci_readl (ohci, &ohci->regs->control);
 129
 130         /* no resumes until devices finish suspending */
 131         if (!autostop) {
 132                 ohci->next_statechange = jiffies + msecs_to_jiffies (5);
 133                 ohci->autostop = 0;
 134                 ohci->rh_state = OHCI_RH_SUSPENDED;
 135         }
 136
 137 done:
 138         return status;
 139 }
 140
 141 static inline struct ed *find_head (struct ed *ed)
 142 {
 143         /* for bulk and control lists */
 144         while (ed->ed_prev)
 145                 ed = ed->ed_prev;
 146         return ed;
 147 }
 148
 149 /* caller has locked the root hub */
 150 static int ohci_rh_resume (struct ohci_hcd *ohci)
 151 __releases(ohci->lock)
 152 __acquires(ohci->lock)
 153 {
 154         struct usb_hcd          *hcd = ohci_to_hcd (ohci);
 155         u32                     temp, enables;
 156         int                     status = -EINPROGRESS;
 157         int                     autostopped = ohci->autostop;
 158
 159         ohci->autostop = 0;
 160         ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
 161
 162         if (ohci->hc_control & (OHCI_CTRL_IR | OHCI_SCHED_ENABLES)) {
 163                 /* this can happen after resuming a swsusp snapshot */
 164                 if (ohci->rh_state != OHCI_RH_RUNNING) {
 165                         ohci_dbg (ohci, "BIOS/SMM active, control %03x\n",
 166                                         ohci->hc_control);
 167                         status = -EBUSY;
 168                 /* this happens when pmcore resumes HC then root */
 169                 } else {
 170                         ohci_dbg (ohci, "duplicate resume\n");
 171                         status = 0;
 172                 }
 173         } else switch (ohci->hc_control & OHCI_CTRL_HCFS) {
 174         case OHCI_USB_SUSPEND:
 175                 ohci->hc_control &= ~(OHCI_CTRL_HCFS|OHCI_SCHED_ENABLES);
 176                 ohci->hc_control |= OHCI_USB_RESUME;
 177                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
 178                 (void) ohci_readl (ohci, &ohci->regs->control);
 179                 ohci_dbg (ohci, "%s root hub\n",
 180                                 autostopped ? "auto-start" : "resume");
 181                 break;
 182         case OHCI_USB_RESUME:
 183                 /* HCFS changes sometime after INTR_RD */
 184                 ohci_dbg(ohci, "%swakeup root hub\n",
 185                                 autostopped ? "auto-" : "");
 186                 break;
 187         case OHCI_USB_OPER:
 188                 /* this can happen after resuming a swsusp snapshot */
 189                 ohci_dbg (ohci, "snapshot resume? reinit\n");
 190                 status = -EBUSY;
 191                 break;
 192         default:                /* RESET, we lost power */
 193                 ohci_dbg (ohci, "lost power\n");
 194                 status = -EBUSY;
 195         }
 196         if (status == -EBUSY) {
 197                 if (!autostopped) {
 198                         spin_unlock_irq (&ohci->lock);
 199                         status = ohci_restart (ohci);
 200
 201                         usb_root_hub_lost_power(hcd->self.root_hub);
 202
 203                         spin_lock_irq (&ohci->lock);
 204                 }
 205                 return status;
 206         }
 207         if (status != -EINPROGRESS)
 208                 return status;
 209         if (autostopped)
 210                 goto skip_resume;
 211         spin_unlock_irq (&ohci->lock);
 212
 213         /* Some controllers (lucent erratum) need extra-long delays */
 214         msleep (20 /* usb 11.5.1.10 */ + 12 /* 32 msec counter */ + 1);
 215
 216         temp = ohci_readl (ohci, &ohci->regs->control);
 217         temp &= OHCI_CTRL_HCFS;
 218         if (temp != OHCI_USB_RESUME) {
 219                 ohci_err (ohci, "controller won't resume\n");
 220                 spin_lock_irq(&ohci->lock);
 221                 return -EBUSY;
 222         }
 223
 224         /* disable old schedule state, reinit from scratch */
 225         ohci_writel (ohci, 0, &ohci->regs->ed_controlhead);
 226         ohci_writel (ohci, 0, &ohci->regs->ed_controlcurrent);
 227         ohci_writel (ohci, 0, &ohci->regs->ed_bulkhead);
 228         ohci_writel (ohci, 0, &ohci->regs->ed_bulkcurrent);
 229         ohci_writel (ohci, 0, &ohci->regs->ed_periodcurrent);
 230         ohci_writel (ohci, (u32) ohci->hcca_dma, &ohci->regs->hcca);
 231
 232         /* Sometimes PCI D3 suspend trashes frame timings ... */
 233         periodic_reinit (ohci);
 234
 235         /*
 236          * The following code is executed with ohci->lock held and
 237          * irqs disabled if and only if autostopped is true.  This
 238          * will cause sparse to warn about a "context imbalance".
 239          */
 240 skip_resume:
 241         /* interrupts might have been disabled */
 242         ohci_writel (ohci, OHCI_INTR_INIT, &ohci->regs->intrenable);
 243         if (ohci->ed_rm_list)
 244                 ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrenable);
 245
 246         /* Then re-enable operations */
 247         ohci_writel (ohci, OHCI_USB_OPER, &ohci->regs->control);
 248         (void) ohci_readl (ohci, &ohci->regs->control);
 249         if (!autostopped)
 250                 msleep (3);
 251
 252         temp = ohci->hc_control;
 253         temp &= OHCI_CTRL_RWC;
 254         temp |= OHCI_CONTROL_INIT | OHCI_USB_OPER;
 255         ohci->hc_control = temp;
 256         ohci_writel (ohci, temp, &ohci->regs->control);
 257         (void) ohci_readl (ohci, &ohci->regs->control);
 258
 259         /* TRSMRCY */
 260         if (!autostopped) {
 261                 msleep (10);
 262                 spin_lock_irq (&ohci->lock);
 263         }
 264         /* now ohci->lock is always held and irqs are always disabled */
 265
 266         /* keep it alive for more than ~5x suspend + resume costs */
 267         ohci->next_statechange = jiffies + STATECHANGE_DELAY;
 268
 269         /* maybe turn schedules back on */
 270         enables = 0;
 271         temp = 0;
 272         if (!ohci->ed_rm_list) {
 273                 if (ohci->ed_controltail) {
 274                         ohci_writel (ohci,
 275                                         find_head (ohci->ed_controltail)->dma,
 276                                         &ohci->regs->ed_controlhead);
 277                         enables |= OHCI_CTRL_CLE;
 278                         temp |= OHCI_CLF;
 279                 }
 280                 if (ohci->ed_bulktail) {
 281                         ohci_writel (ohci, find_head (ohci->ed_bulktail)->dma,
 282                                 &ohci->regs->ed_bulkhead);
 283                         enables |= OHCI_CTRL_BLE;
 284                         temp |= OHCI_BLF;
 285                 }
 286         }
 287         if (hcd->self.bandwidth_isoc_reqs || hcd->self.bandwidth_int_reqs)
 288                 enables |= OHCI_CTRL_PLE|OHCI_CTRL_IE;
 289         if (enables) {
 290                 ohci_dbg (ohci, "restarting schedules ... %08x\n", enables);
 291                 ohci->hc_control |= enables;
 292                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
 293                 if (temp)
 294                         ohci_writel (ohci, temp, &ohci->regs->cmdstatus);
 295                 (void) ohci_readl (ohci, &ohci->regs->control);
 296         }
 297
 298         ohci->rh_state = OHCI_RH_RUNNING;
 299         return 0;
 300 }
 301
 302 static int ohci_bus_suspend (struct usb_hcd *hcd)
 303 {
 304         struct ohci_hcd         *ohci = hcd_to_ohci (hcd);
 305         int                     rc;
 306
 307         spin_lock_irq (&ohci->lock);
 308
 309         if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
 310                 rc = -ESHUTDOWN;
 311         else
 312                 rc = ohci_rh_suspend (ohci, 0);
 313         spin_unlock_irq (&ohci->lock);
 314         return rc;
 315 }
 316
 317 static int ohci_bus_resume (struct usb_hcd *hcd)
 318 {
 319         struct ohci_hcd         *ohci = hcd_to_ohci (hcd);
 320         int                     rc;
 321
 322         if (time_before (jiffies, ohci->next_statechange))
 323                 msleep(5);
 324
 325         spin_lock_irq (&ohci->lock);
 326
 327         if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
 328                 rc = -ESHUTDOWN;
 329         else
 330                 rc = ohci_rh_resume (ohci);
 331         spin_unlock_irq (&ohci->lock);
 332
 333         /* poll until we know a device is connected or we autostop */
 334         if (rc == 0)
 335                 usb_hcd_poll_rh_status(hcd);
 336         return rc;
 337 }
 338
 339 /* Carry out polling-, autostop-, and autoresume-related state changes */
 340 static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
 341                 int any_connected, int rhsc_status)
 342 {
 343         int     poll_rh = 1;
 344         int     rhsc_enable;
 345
 346         /* Some broken controllers never turn off RHSC in the interrupt
 347          * status register.  For their sake we won't re-enable RHSC
 348          * interrupts if the interrupt bit is already active.
 349          */
 350         rhsc_enable = ohci_readl(ohci, &ohci->regs->intrenable) &
 351                         OHCI_INTR_RHSC;
 352
 353         switch (ohci->hc_control & OHCI_CTRL_HCFS) {
 354         case OHCI_USB_OPER:
 355                 /* If no status changes are pending, enable RHSC interrupts. */
 356                 if (!rhsc_enable && !rhsc_status && !changed) {
 357                         rhsc_enable = OHCI_INTR_RHSC;
 358                         ohci_writel(ohci, rhsc_enable, &ohci->regs->intrenable);
 359                 }
 360
 361                 /* Keep on polling until we know a device is connected
 362                  * and RHSC is enabled, or until we autostop.
 363                  */
 364                 if (!ohci->autostop) {
 365                         if (any_connected ||
 366                                         !device_may_wakeup(&ohci_to_hcd(ohci)
 367                                                 ->self.root_hub->dev)) {
 368                                 if (rhsc_enable)
 369                                         poll_rh = 0;
 370                         } else {
 371                                 ohci->autostop = 1;
 372                                 ohci->next_statechange = jiffies + HZ;
 373                         }
 374
 375                 /* if no devices have been attached for one second, autostop */
 376                 } else {
 377                         if (changed || any_connected) {
 378                                 ohci->autostop = 0;
 379                                 ohci->next_statechange = jiffies +
 380                                                 STATECHANGE_DELAY;
 381                         } else if (time_after_eq(jiffies,
 382                                                 ohci->next_statechange)
 383                                         && !ohci->ed_rm_list
 384                                         && !(ohci->hc_control &
 385                                                 OHCI_SCHED_ENABLES)) {
 386                                 ohci_rh_suspend(ohci, 1);
 387                                 if (rhsc_enable)
 388                                         poll_rh = 0;
 389                         }
 390                 }
 391                 break;
 392
 393         case OHCI_USB_SUSPEND:
 394         case OHCI_USB_RESUME:
 395                 /* if there is a port change, autostart or ask to be resumed */
 396                 if (changed) {
 397                         if (ohci->autostop)
 398                                 ohci_rh_resume(ohci);
 399                         else
 400                                 usb_hcd_resume_root_hub(ohci_to_hcd(ohci));
 401
 402                 /* If remote wakeup is disabled, stop polling */
 403                 } else if (!ohci->autostop &&
 404                                 !ohci_to_hcd(ohci)->self.root_hub->
 405                                         do_remote_wakeup) {
 406                         poll_rh = 0;
 407
 408                 } else {
 409                         /* If no status changes are pending,
 410                          * enable RHSC interrupts
 411                          */
 412                         if (!rhsc_enable && !rhsc_status) {
 413                                 rhsc_enable = OHCI_INTR_RHSC;
 414                                 ohci_writel(ohci, rhsc_enable,
 415                                                 &ohci->regs->intrenable);
 416                         }
 417                         /* Keep polling until RHSC is enabled */
 418                         if (rhsc_enable)
 419                                 poll_rh = 0;
 420                 }
 421                 break;
 422         }
 423         return poll_rh;
 424 }
 425
 426 #else   /* CONFIG_PM */
 427
 428 static inline int ohci_rh_resume(struct ohci_hcd *ohci)
 429 {
 430         return 0;
 431 }
 432
 433 /* Carry out polling-related state changes.
 434  * autostop isn't used when CONFIG_PM is turned off.
 435  */
 436 static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
 437                 int any_connected, int rhsc_status)
 438 {
 439         /* If RHSC is enabled, don't poll */
 440         if (ohci_readl(ohci, &ohci->regs->intrenable) & OHCI_INTR_RHSC)
 441                 return 0;
 442
 443         /* If status changes are pending, continue polling.
 444          * Conversely, if no status changes are pending but the RHSC
 445          * status bit was set, then RHSC may be broken so continue polling.
 446          */
 447         if (changed || rhsc_status)
 448                 return 1;
 449
 450         /* It's safe to re-enable RHSC interrupts */
 451         ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrenable);
 452         return 0;
 453 }
 454
 455 #endif  /* CONFIG_PM */
 456
 457 /*-------------------------------------------------------------------------*/
 458
 459 /* build "status change" packet (one or two bytes) from HC registers */
 460
 461 int ohci_hub_status_data(struct usb_hcd *hcd, char *buf)
 462 {
 463         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
 464         int             i, changed = 0, length = 1;
 465         int             any_connected = 0;
 466         int             rhsc_status;
 467         unsigned long   flags;
 468
 469         spin_lock_irqsave (&ohci->lock, flags);
 470         if (!HCD_HW_ACCESSIBLE(hcd))
 471                 goto done;
 472
 473         /* undocumented erratum seen on at least rev D */
 474         if ((ohci->flags & OHCI_QUIRK_AMD756)
 475                         && (roothub_a (ohci) & RH_A_NDP) > MAX_ROOT_PORTS) {
 476                 ohci_warn (ohci, "bogus NDP, rereads as NDP=%d\n",
 477                           ohci_readl (ohci, &ohci->regs->roothub.a) & RH_A_NDP);
 478                 /* retry later; "should not happen" */
 479                 goto done;
 480         }
 481
 482         /* init status */
 483         if (roothub_status (ohci) & (RH_HS_LPSC | RH_HS_OCIC))
 484                 buf [0] = changed = 1;
 485         else
 486                 buf [0] = 0;
 487         if (ohci->num_ports > 7) {
 488                 buf [1] = 0;
 489                 length++;
 490         }
 491
 492         /* Clear the RHSC status flag before reading the port statuses */
 493         ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrstatus);
 494         rhsc_status = ohci_readl(ohci, &ohci->regs->intrstatus) &
 495                         OHCI_INTR_RHSC;
 496
 497         /* look at each port */
 498         for (i = 0; i < ohci->num_ports; i++) {
 499                 u32     status = roothub_portstatus (ohci, i);
 500
 501                 /* can't autostop if ports are connected */
 502                 any_connected |= (status & RH_PS_CCS);
 503
 504                 if (status & (RH_PS_CSC | RH_PS_PESC | RH_PS_PSSC
 505                                 | RH_PS_OCIC | RH_PS_PRSC)) {
 506                         changed = 1;
 507                         if (i < 7)
 508                             buf [0] |= 1 << (i + 1);
 509                         else
 510                             buf [1] |= 1 << (i - 7);
 511                 }
 512         }
 513
 514         if (ohci_root_hub_state_changes(ohci, changed,
 515                         any_connected, rhsc_status))
 516                 set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
 517         else
 518                 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
 519
 520
 521 done:
 522         spin_unlock_irqrestore (&ohci->lock, flags);
 523
 524         return changed ? length : 0;
 525 }
 526 EXPORT_SYMBOL_GPL(ohci_hub_status_data);
 527
 528 /*-------------------------------------------------------------------------*/
 529
 530 static void
 531 ohci_hub_descriptor (
 532         struct ohci_hcd                 *ohci,
 533         struct usb_hub_descriptor       *desc
 534 ) {
 535         u32             rh = roothub_a (ohci);
 536         u16             temp;
 537
 538         desc->bDescriptorType = 0x29;
 539         desc->bPwrOn2PwrGood = (rh & RH_A_POTPGT) >> 24;
 540         desc->bHubContrCurrent = 0;
 541
 542         desc->bNbrPorts = ohci->num_ports;
 543         temp = 1 + (ohci->num_ports / 8);
 544         desc->bDescLength = 7 + 2 * temp;
 545
 546         temp = 0;
 547         if (rh & RH_A_NPS)              /* no power switching? */
 548             temp |= 0x0002;
 549         if (rh & RH_A_PSM)              /* per-port power switching? */
 550             temp |= 0x0001;
 551         if (rh & RH_A_NOCP)             /* no overcurrent reporting? */
 552             temp |= 0x0010;
 553         else if (rh & RH_A_OCPM)        /* per-port overcurrent reporting? */
 554             temp |= 0x0008;
 555         desc->wHubCharacteristics = cpu_to_le16(temp);
 556
 557         /* ports removable, and usb 1.0 legacy PortPwrCtrlMask */
 558         rh = roothub_b (ohci);
 559         memset(desc->u.hs.DeviceRemovable, 0xff,
 560                         sizeof(desc->u.hs.DeviceRemovable));
 561         desc->u.hs.DeviceRemovable[0] = rh & RH_B_DR;
 562         if (ohci->num_ports > 7) {
 563                 desc->u.hs.DeviceRemovable[1] = (rh & RH_B_DR) >> 8;
 564                 desc->u.hs.DeviceRemovable[2] = 0xff;
 565         } else
 566                 desc->u.hs.DeviceRemovable[1] = 0xff;
 567 }
 568
 569 /*-------------------------------------------------------------------------*/
 570
 571 #ifdef  CONFIG_USB_OTG
 572
 573 static int ohci_start_port_reset (struct usb_hcd *hcd, unsigned port)
 574 {
 575         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
 576         u32                     status;
 577
 578         if (!port)
 579                 return -EINVAL;
 580         port--;
 581
 582         /* start port reset before HNP protocol times out */
 583         status = ohci_readl(ohci, &ohci->regs->roothub.portstatus [port]);
 584         if (!(status & RH_PS_CCS))
 585                 return -ENODEV;
 586
 587         /* khubd will finish the reset later */
 588         ohci_writel(ohci, RH_PS_PRS, &ohci->regs->roothub.portstatus [port]);
 589         return 0;
 590 }
 591
 592 #else
 593
 594 #define ohci_start_port_reset           NULL
 595
 596 #endif
 597
 598 /*-------------------------------------------------------------------------*/
 599
 600
 601 /* See usb 7.1.7.5:  root hubs must issue at least 50 msec reset signaling,
 602  * not necessarily continuous ... to guard against resume signaling.
 603  */
 604 #define PORT_RESET_MSEC         50
 605
 606 /* this timer value might be vendor-specific ... */
 607 #define PORT_RESET_HW_MSEC      10
 608
 609 /* wrap-aware logic morphed from <linux/jiffies.h> */
 610 #define tick_before(t1,t2) ((s16)(((s16)(t1))-((s16)(t2))) < 0)
 611
 612 /* called from some task, normally khubd */
 613 static inline int root_port_reset (struct ohci_hcd *ohci, unsigned port)
 614 {
 615         __hc32 __iomem *portstat = &ohci->regs->roothub.portstatus [port];
 616         u32     temp = 0;
 617         u16     now = ohci_readl(ohci, &ohci->regs->fmnumber);
 618         u16     reset_done = now + PORT_RESET_MSEC;
 619         int     limit_1 = DIV_ROUND_UP(PORT_RESET_MSEC, PORT_RESET_HW_MSEC);
 620
 621         /* build a "continuous enough" reset signal, with up to
 622          * 3msec gap between pulses.  scheduler HZ==100 must work;
 623          * this might need to be deadline-scheduled.
 624          */
 625         do {
 626                 int limit_2;
 627
 628                 /* spin until any current reset finishes */
 629                 limit_2 = PORT_RESET_HW_MSEC * 2;
 630                 while (--limit_2 >= 0) {
 631                         temp = ohci_readl (ohci, portstat);
 632                         /* handle e.g. CardBus eject */
 633                         if (temp == ~(u32)0)
 634                                 return -ESHUTDOWN;
 635                         if (!(temp & RH_PS_PRS))
 636                                 break;
 637                         udelay (500);
 638                 }
 639
 640                 /* timeout (a hardware error) has been observed when
 641                  * EHCI sets CF while this driver is resetting a port;
 642                  * presumably other disconnect paths might do it too.
 643                  */
 644                 if (limit_2 < 0) {
 645                         ohci_dbg(ohci,
 646                                 "port[%d] reset timeout, stat %08x\n",
 647                                 port, temp);
 648                         break;
 649                 }
 650
 651                 if (!(temp & RH_PS_CCS))
 652                         break;
 653                 if (temp & RH_PS_PRSC)
 654                         ohci_writel (ohci, RH_PS_PRSC, portstat);
 655
 656                 /* start the next reset, sleep till it's probably done */
 657                 ohci_writel (ohci, RH_PS_PRS, portstat);
 658                 msleep(PORT_RESET_HW_MSEC);
 659                 now = ohci_readl(ohci, &ohci->regs->fmnumber);
 660         } while (tick_before(now, reset_done) && --limit_1 >= 0);
 661
 662         /* caller synchronizes using PRSC ... and handles PRS
 663          * still being set when this returns.
 664          */
 665
 666         return 0;
 667 }
 668
 669 int ohci_hub_control(
 670         struct usb_hcd  *hcd,
 671         u16             typeReq,
 672         u16             wValue,
 673         u16             wIndex,
 674         char            *buf,
 675         u16             wLength
 676 ) {
 677         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
 678         int             ports = ohci->num_ports;
 679         u32             temp;
 680         int             retval = 0;
 681
 682         if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
 683                 return -ESHUTDOWN;
 684
 685         switch (typeReq) {
 686         case ClearHubFeature:
 687                 switch (wValue) {
 688                 case C_HUB_OVER_CURRENT:
 689                         ohci_writel (ohci, RH_HS_OCIC,
 690                                         &ohci->regs->roothub.status);
 691                 case C_HUB_LOCAL_POWER:
 692                         break;
 693                 default:
 694                         goto error;
 695                 }
 696                 break;
 697         case ClearPortFeature:
 698                 if (!wIndex || wIndex > ports)
 699                         goto error;
 700                 wIndex--;
 701
 702                 switch (wValue) {
 703                 case USB_PORT_FEAT_ENABLE:
 704                         temp = RH_PS_CCS;
 705                         break;
 706                 case USB_PORT_FEAT_C_ENABLE:
 707                         temp = RH_PS_PESC;
 708                         break;
 709                 case USB_PORT_FEAT_SUSPEND:
 710                         temp = RH_PS_POCI;
 711                         break;
 712                 case USB_PORT_FEAT_C_SUSPEND:
 713                         temp = RH_PS_PSSC;
 714                         break;
 715                 case USB_PORT_FEAT_POWER:
 716                         temp = RH_PS_LSDA;
 717                         break;
 718                 case USB_PORT_FEAT_C_CONNECTION:
 719                         temp = RH_PS_CSC;
 720                         break;
 721                 case USB_PORT_FEAT_C_OVER_CURRENT:
 722                         temp = RH_PS_OCIC;
 723                         break;
 724                 case USB_PORT_FEAT_C_RESET:
 725                         temp = RH_PS_PRSC;
 726                         break;
 727                 default:
 728                         goto error;
 729                 }
 730                 ohci_writel (ohci, temp,
 731                                 &ohci->regs->roothub.portstatus [wIndex]);
 732                 // ohci_readl (ohci, &ohci->regs->roothub.portstatus [wIndex]);
 733                 break;
 734         case GetHubDescriptor:
 735                 ohci_hub_descriptor (ohci, (struct usb_hub_descriptor *) buf);
 736                 break;
 737         case GetHubStatus:
 738                 temp = roothub_status (ohci) & ~(RH_HS_CRWE | RH_HS_DRWE);
 739                 put_unaligned_le32(temp, buf);
 740                 break;
 741         case GetPortStatus:
 742                 if (!wIndex || wIndex > ports)
 743                         goto error;
 744                 wIndex--;
 745                 temp = roothub_portstatus (ohci, wIndex);
 746                 put_unaligned_le32(temp, buf);
 747
 748                 if (*(u16*)(buf+2))     /* only if wPortChange is interesting */
 749                         dbg_port(ohci, "GetStatus", wIndex, temp);
 750                 break;
 751         case SetHubFeature:
 752                 switch (wValue) {
 753                 case C_HUB_OVER_CURRENT:
 754                         // FIXME:  this can be cleared, yes?
 755                 case C_HUB_LOCAL_POWER:
 756                         break;
 757                 default:
 758                         goto error;
 759                 }
 760                 break;
 761         case SetPortFeature:
 762                 if (!wIndex || wIndex > ports)
 763                         goto error;
 764                 wIndex--;
 765                 switch (wValue) {
 766                 case USB_PORT_FEAT_SUSPEND:
 767 #ifdef  CONFIG_USB_OTG
 768                         if (hcd->self.otg_port == (wIndex + 1)
 769                                         && hcd->self.b_hnp_enable)
 770                                 ohci->start_hnp(ohci);
 771                         else
 772 #endif
 773                         ohci_writel (ohci, RH_PS_PSS,
 774                                 &ohci->regs->roothub.portstatus [wIndex]);
 775                         break;
 776                 case USB_PORT_FEAT_POWER:
 777                         ohci_writel (ohci, RH_PS_PPS,
 778                                 &ohci->regs->roothub.portstatus [wIndex]);
 779                         break;
 780                 case USB_PORT_FEAT_RESET:
 781                         retval = root_port_reset (ohci, wIndex);
 782                         break;
 783                 default:
 784                         goto error;
 785                 }
 786                 break;
 787
 788         default:
 789 error:
 790                 /* "protocol stall" on error */
 791                 retval = -EPIPE;
 792         }
 793         return retval;
 794 }
 795 EXPORT_SYMBOL_GPL(ohci_hub_control);