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 dl_done_list (struct ohci_hcd *);
  43 static void finish_unlinks (struct ohci_hcd *, u16);
  44
  45 #ifdef  CONFIG_PM
  46 static int ohci_rh_suspend (struct ohci_hcd *ohci, int autostop)
  47 __releases(ohci->lock)
  48 __acquires(ohci->lock)
  49 {
  50         int                     status = 0;
  51
  52         ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
  53         switch (ohci->hc_control & OHCI_CTRL_HCFS) {
  54         case OHCI_USB_RESUME:
  55                 ohci_dbg (ohci, "resume/suspend?\n");
  56                 ohci->hc_control &= ~OHCI_CTRL_HCFS;
  57                 ohci->hc_control |= OHCI_USB_RESET;
  58                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
  59                 (void) ohci_readl (ohci, &ohci->regs->control);
  60                 /* FALL THROUGH */
  61         case OHCI_USB_RESET:
  62                 status = -EBUSY;
  63                 ohci_dbg (ohci, "needs reinit!\n");
  64                 goto done;
  65         case OHCI_USB_SUSPEND:
  66                 if (!ohci->autostop) {
  67                         ohci_dbg (ohci, "already suspended\n");
  68                         goto done;
  69                 }
  70         }
  71         ohci_dbg (ohci, "%s root hub\n",
  72                         autostop ? "auto-stop" : "suspend");
  73
  74         /* First stop any processing */
  75         if (!autostop && (ohci->hc_control & OHCI_SCHED_ENABLES)) {
  76                 ohci->hc_control &= ~OHCI_SCHED_ENABLES;
  77                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
  78                 ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
  79                 ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrstatus);
  80
  81                 /* sched disables take effect on the next frame,
  82                  * then the last WDH could take 6+ msec
  83                  */
  84                 ohci_dbg (ohci, "stopping schedules ...\n");
  85                 ohci->autostop = 0;
  86                 spin_unlock_irq (&ohci->lock);
  87                 msleep (8);
  88                 spin_lock_irq (&ohci->lock);
  89         }
  90         dl_done_list (ohci);
  91         finish_unlinks (ohci, ohci_frame_no(ohci));
  92
  93         /*
  94          * Some controllers don't handle "global" suspend properly if
  95          * there are unsuspended ports.  For these controllers, put all
  96          * the enabled ports into suspend before suspending the root hub.
  97          */
  98         if (ohci->flags & OHCI_QUIRK_GLOBAL_SUSPEND) {
  99                 __hc32 __iomem  *portstat = ohci->regs->roothub.portstatus;
 100                 int             i;
 101                 unsigned        temp;
 102
 103                 for (i = 0; i < ohci->num_ports; (++i, ++portstat)) {
 104                         temp = ohci_readl(ohci, portstat);
 105                         if ((temp & (RH_PS_PES | RH_PS_PSS)) ==
 106                                         RH_PS_PES)
 107                                 ohci_writel(ohci, RH_PS_PSS, portstat);
 108                 }
 109         }
 110
 111         /* maybe resume can wake root hub */
 112         if (ohci_to_hcd(ohci)->self.root_hub->do_remote_wakeup || autostop) {
 113                 ohci->hc_control |= OHCI_CTRL_RWE;
 114         } else {
 115                 ohci_writel(ohci, OHCI_INTR_RHSC | OHCI_INTR_RD,
 116                                 &ohci->regs->intrdisable);
 117                 ohci->hc_control &= ~OHCI_CTRL_RWE;
 118         }
 119
 120         /* Suspend hub ... this is the "global (to this bus) suspend" mode,
 121          * which doesn't imply ports will first be individually suspended.
 122          */
 123         ohci->hc_control &= ~OHCI_CTRL_HCFS;
 124         ohci->hc_control |= OHCI_USB_SUSPEND;
 125         ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
 126         (void) ohci_readl (ohci, &ohci->regs->control);
 127
 128         /* no resumes until devices finish suspending */
 129         if (!autostop) {
 130                 ohci->next_statechange = jiffies + msecs_to_jiffies (5);
 131                 ohci->autostop = 0;
 132                 ohci->rh_state = OHCI_RH_SUSPENDED;
 133         }
 134
 135 done:
 136         return status;
 137 }
 138
 139 static inline struct ed *find_head (struct ed *ed)
 140 {
 141         /* for bulk and control lists */
 142         while (ed->ed_prev)
 143                 ed = ed->ed_prev;
 144         return ed;
 145 }
 146
 147 /* caller has locked the root hub */
 148 static int ohci_rh_resume (struct ohci_hcd *ohci)
 149 __releases(ohci->lock)
 150 __acquires(ohci->lock)
 151 {
 152         struct usb_hcd          *hcd = ohci_to_hcd (ohci);
 153         u32                     temp, enables;
 154         int                     status = -EINPROGRESS;
 155         int                     autostopped = ohci->autostop;
 156
 157         ohci->autostop = 0;
 158         ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
 159
 160         if (ohci->hc_control & (OHCI_CTRL_IR | OHCI_SCHED_ENABLES)) {
 161                 /* this can happen after resuming a swsusp snapshot */
 162                 if (ohci->rh_state != OHCI_RH_RUNNING) {
 163                         ohci_dbg (ohci, "BIOS/SMM active, control %03x\n",
 164                                         ohci->hc_control);
 165                         status = -EBUSY;
 166                 /* this happens when pmcore resumes HC then root */
 167                 } else {
 168                         ohci_dbg (ohci, "duplicate resume\n");
 169                         status = 0;
 170                 }
 171         } else switch (ohci->hc_control & OHCI_CTRL_HCFS) {
 172         case OHCI_USB_SUSPEND:
 173                 ohci->hc_control &= ~(OHCI_CTRL_HCFS|OHCI_SCHED_ENABLES);
 174                 ohci->hc_control |= OHCI_USB_RESUME;
 175                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
 176                 (void) ohci_readl (ohci, &ohci->regs->control);
 177                 ohci_dbg (ohci, "%s root hub\n",
 178                                 autostopped ? "auto-start" : "resume");
 179                 break;
 180         case OHCI_USB_RESUME:
 181                 /* HCFS changes sometime after INTR_RD */
 182                 ohci_dbg(ohci, "%swakeup root hub\n",
 183                                 autostopped ? "auto-" : "");
 184                 break;
 185         case OHCI_USB_OPER:
 186                 /* this can happen after resuming a swsusp snapshot */
 187                 ohci_dbg (ohci, "snapshot resume? reinit\n");
 188                 status = -EBUSY;
 189                 break;
 190         default:                /* RESET, we lost power */
 191                 ohci_dbg (ohci, "lost power\n");
 192                 status = -EBUSY;
 193         }
 194         if (status == -EBUSY) {
 195                 if (!autostopped) {
 196                         spin_unlock_irq (&ohci->lock);
 197                         status = ohci_restart (ohci);
 198
 199                         usb_root_hub_lost_power(hcd->self.root_hub);
 200
 201                         spin_lock_irq (&ohci->lock);
 202                 }
 203                 return status;
 204         }
 205         if (status != -EINPROGRESS)
 206                 return status;
 207         if (autostopped)
 208                 goto skip_resume;
 209         spin_unlock_irq (&ohci->lock);
 210
 211         /* Some controllers (lucent erratum) need extra-long delays */
 212         msleep (20 /* usb 11.5.1.10 */ + 12 /* 32 msec counter */ + 1);
 213
 214         temp = ohci_readl (ohci, &ohci->regs->control);
 215         temp &= OHCI_CTRL_HCFS;
 216         if (temp != OHCI_USB_RESUME) {
 217                 ohci_err (ohci, "controller won't resume\n");
 218                 spin_lock_irq(&ohci->lock);
 219                 return -EBUSY;
 220         }
 221
 222         /* disable old schedule state, reinit from scratch */
 223         ohci_writel (ohci, 0, &ohci->regs->ed_controlhead);
 224         ohci_writel (ohci, 0, &ohci->regs->ed_controlcurrent);
 225         ohci_writel (ohci, 0, &ohci->regs->ed_bulkhead);
 226         ohci_writel (ohci, 0, &ohci->regs->ed_bulkcurrent);
 227         ohci_writel (ohci, 0, &ohci->regs->ed_periodcurrent);
 228         ohci_writel (ohci, (u32) ohci->hcca_dma, &ohci->regs->hcca);
 229
 230         /* Sometimes PCI D3 suspend trashes frame timings ... */
 231         periodic_reinit (ohci);
 232
 233         /* the following code is executed with ohci->lock held and
 234          * irqs disabled if and only if autostopped is true
 235          */
 236
 237 skip_resume:
 238         /* interrupts might have been disabled */
 239         ohci_writel (ohci, OHCI_INTR_INIT, &ohci->regs->intrenable);
 240         if (ohci->ed_rm_list)
 241                 ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrenable);
 242
 243         /* Then re-enable operations */
 244         ohci_writel (ohci, OHCI_USB_OPER, &ohci->regs->control);
 245         (void) ohci_readl (ohci, &ohci->regs->control);
 246         if (!autostopped)
 247                 msleep (3);
 248
 249         temp = ohci->hc_control;
 250         temp &= OHCI_CTRL_RWC;
 251         temp |= OHCI_CONTROL_INIT | OHCI_USB_OPER;
 252         ohci->hc_control = temp;
 253         ohci_writel (ohci, temp, &ohci->regs->control);
 254         (void) ohci_readl (ohci, &ohci->regs->control);
 255
 256         /* TRSMRCY */
 257         if (!autostopped) {
 258                 msleep (10);
 259                 spin_lock_irq (&ohci->lock);
 260         }
 261         /* now ohci->lock is always held and irqs are always disabled */
 262
 263         /* keep it alive for more than ~5x suspend + resume costs */
 264         ohci->next_statechange = jiffies + STATECHANGE_DELAY;
 265
 266         /* maybe turn schedules back on */
 267         enables = 0;
 268         temp = 0;
 269         if (!ohci->ed_rm_list) {
 270                 if (ohci->ed_controltail) {
 271                         ohci_writel (ohci,
 272                                         find_head (ohci->ed_controltail)->dma,
 273                                         &ohci->regs->ed_controlhead);
 274                         enables |= OHCI_CTRL_CLE;
 275                         temp |= OHCI_CLF;
 276                 }
 277                 if (ohci->ed_bulktail) {
 278                         ohci_writel (ohci, find_head (ohci->ed_bulktail)->dma,
 279                                 &ohci->regs->ed_bulkhead);
 280                         enables |= OHCI_CTRL_BLE;
 281                         temp |= OHCI_BLF;
 282                 }
 283         }
 284         if (hcd->self.bandwidth_isoc_reqs || hcd->self.bandwidth_int_reqs)
 285                 enables |= OHCI_CTRL_PLE|OHCI_CTRL_IE;
 286         if (enables) {
 287                 ohci_dbg (ohci, "restarting schedules ... %08x\n", enables);
 288                 ohci->hc_control |= enables;
 289                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
 290                 if (temp)
 291                         ohci_writel (ohci, temp, &ohci->regs->cmdstatus);
 292                 (void) ohci_readl (ohci, &ohci->regs->control);
 293         }
 294
 295         ohci->rh_state = OHCI_RH_RUNNING;
 296         return 0;
 297 }
 298
 299 static int ohci_bus_suspend (struct usb_hcd *hcd)
 300 {
 301         struct ohci_hcd         *ohci = hcd_to_ohci (hcd);
 302         int                     rc;
 303
 304         spin_lock_irq (&ohci->lock);
 305
 306         if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
 307                 rc = -ESHUTDOWN;
 308         else
 309                 rc = ohci_rh_suspend (ohci, 0);
 310         spin_unlock_irq (&ohci->lock);
 311         return rc;
 312 }
 313
 314 static int ohci_bus_resume (struct usb_hcd *hcd)
 315 {
 316         struct ohci_hcd         *ohci = hcd_to_ohci (hcd);
 317         int                     rc;
 318
 319         if (time_before (jiffies, ohci->next_statechange))
 320                 msleep(5);
 321
 322         spin_lock_irq (&ohci->lock);
 323
 324         if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
 325                 rc = -ESHUTDOWN;
 326         else
 327                 rc = ohci_rh_resume (ohci);
 328         spin_unlock_irq (&ohci->lock);
 329
 330         /* poll until we know a device is connected or we autostop */
 331         if (rc == 0)
 332                 usb_hcd_poll_rh_status(hcd);
 333         return rc;
 334 }
 335
 336 /* Carry out polling-, autostop-, and autoresume-related state changes */
 337 static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
 338                 int any_connected, int rhsc_status)
 339 {
 340         int     poll_rh = 1;
 341         int     rhsc_enable;
 342
 343         /* Some broken controllers never turn off RHSC in the interrupt
 344          * status register.  For their sake we won't re-enable RHSC
 345          * interrupts if the interrupt bit is already active.
 346          */
 347         rhsc_enable = ohci_readl(ohci, &ohci->regs->intrenable) &
 348                         OHCI_INTR_RHSC;
 349
 350         switch (ohci->hc_control & OHCI_CTRL_HCFS) {
 351         case OHCI_USB_OPER:
 352                 /* If no status changes are pending, enable RHSC interrupts. */
 353                 if (!rhsc_enable && !rhsc_status && !changed) {
 354                         rhsc_enable = OHCI_INTR_RHSC;
 355                         ohci_writel(ohci, rhsc_enable, &ohci->regs->intrenable);
 356                 }
 357
 358                 /* Keep on polling until we know a device is connected
 359                  * and RHSC is enabled, or until we autostop.
 360                  */
 361                 if (!ohci->autostop) {
 362                         if (any_connected ||
 363                                         !device_may_wakeup(&ohci_to_hcd(ohci)
 364                                                 ->self.root_hub->dev)) {
 365                                 if (rhsc_enable)
 366                                         poll_rh = 0;
 367                         } else {
 368                                 ohci->autostop = 1;
 369                                 ohci->next_statechange = jiffies + HZ;
 370                         }
 371
 372                 /* if no devices have been attached for one second, autostop */
 373                 } else {
 374                         if (changed || any_connected) {
 375                                 ohci->autostop = 0;
 376                                 ohci->next_statechange = jiffies +
 377                                                 STATECHANGE_DELAY;
 378                         } else if (time_after_eq(jiffies,
 379                                                 ohci->next_statechange)
 380                                         && !ohci->ed_rm_list
 381                                         && !(ohci->hc_control &
 382                                                 OHCI_SCHED_ENABLES)) {
 383                                 ohci_rh_suspend(ohci, 1);
 384                                 if (rhsc_enable)
 385                                         poll_rh = 0;
 386                         }
 387                 }
 388                 break;
 389
 390         case OHCI_USB_SUSPEND:
 391         case OHCI_USB_RESUME:
 392                 /* if there is a port change, autostart or ask to be resumed */
 393                 if (changed) {
 394                         if (ohci->autostop)
 395                                 ohci_rh_resume(ohci);
 396                         else
 397                                 usb_hcd_resume_root_hub(ohci_to_hcd(ohci));
 398
 399                 /* If remote wakeup is disabled, stop polling */
 400                 } else if (!ohci->autostop &&
 401                                 !ohci_to_hcd(ohci)->self.root_hub->
 402                                         do_remote_wakeup) {
 403                         poll_rh = 0;
 404
 405                 } else {
 406                         /* If no status changes are pending,
 407                          * enable RHSC interrupts
 408                          */
 409                         if (!rhsc_enable && !rhsc_status) {
 410                                 rhsc_enable = OHCI_INTR_RHSC;
 411                                 ohci_writel(ohci, rhsc_enable,
 412                                                 &ohci->regs->intrenable);
 413                         }
 414                         /* Keep polling until RHSC is enabled */
 415                         if (rhsc_enable)
 416                                 poll_rh = 0;
 417                 }
 418                 break;
 419         }
 420         return poll_rh;
 421 }
 422
 423 #else   /* CONFIG_PM */
 424
 425 static inline int ohci_rh_resume(struct ohci_hcd *ohci)
 426 {
 427         return 0;
 428 }
 429
 430 /* Carry out polling-related state changes.
 431  * autostop isn't used when CONFIG_PM is turned off.
 432  */
 433 static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
 434                 int any_connected, int rhsc_status)
 435 {
 436         /* If RHSC is enabled, don't poll */
 437         if (ohci_readl(ohci, &ohci->regs->intrenable) & OHCI_INTR_RHSC)
 438                 return 0;
 439
 440         /* If status changes are pending, continue polling.
 441          * Conversely, if no status changes are pending but the RHSC
 442          * status bit was set, then RHSC may be broken so continue polling.
 443          */
 444         if (changed || rhsc_status)
 445                 return 1;
 446
 447         /* It's safe to re-enable RHSC interrupts */
 448         ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrenable);
 449         return 0;
 450 }
 451
 452 #endif  /* CONFIG_PM */
 453
 454 /*-------------------------------------------------------------------------*/
 455
 456 /* build "status change" packet (one or two bytes) from HC registers */
 457
 458 static int
 459 ohci_hub_status_data (struct usb_hcd *hcd, char *buf)
 460 {
 461         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
 462         int             i, changed = 0, length = 1;
 463         int             any_connected = 0;
 464         int             rhsc_status;
 465         unsigned long   flags;
 466
 467         spin_lock_irqsave (&ohci->lock, flags);
 468         if (!HCD_HW_ACCESSIBLE(hcd))
 469                 goto done;
 470
 471         /* undocumented erratum seen on at least rev D */
 472         if ((ohci->flags & OHCI_QUIRK_AMD756)
 473                         && (roothub_a (ohci) & RH_A_NDP) > MAX_ROOT_PORTS) {
 474                 ohci_warn (ohci, "bogus NDP, rereads as NDP=%d\n",
 475                           ohci_readl (ohci, &ohci->regs->roothub.a) & RH_A_NDP);
 476                 /* retry later; "should not happen" */
 477                 goto done;
 478         }
 479
 480         /* init status */
 481         if (roothub_status (ohci) & (RH_HS_LPSC | RH_HS_OCIC))
 482                 buf [0] = changed = 1;
 483         else
 484                 buf [0] = 0;
 485         if (ohci->num_ports > 7) {
 486                 buf [1] = 0;
 487                 length++;
 488         }
 489
 490         /* Clear the RHSC status flag before reading the port statuses */
 491         ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrstatus);
 492         rhsc_status = ohci_readl(ohci, &ohci->regs->intrstatus) &
 493                         OHCI_INTR_RHSC;
 494
 495         /* look at each port */
 496         for (i = 0; i < ohci->num_ports; i++) {
 497                 u32     status = roothub_portstatus (ohci, i);
 498
 499                 /* can't autostop if ports are connected */
 500                 any_connected |= (status & RH_PS_CCS);
 501
 502                 if (status & (RH_PS_CSC | RH_PS_PESC | RH_PS_PSSC
 503                                 | RH_PS_OCIC | RH_PS_PRSC)) {
 504                         changed = 1;
 505                         if (i < 7)
 506                             buf [0] |= 1 << (i + 1);
 507                         else
 508                             buf [1] |= 1 << (i - 7);
 509                 }
 510         }
 511
 512         if (ohci_root_hub_state_changes(ohci, changed,
 513                         any_connected, rhsc_status))
 514                 set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
 515         else
 516                 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
 517
 518
 519 done:
 520         spin_unlock_irqrestore (&ohci->lock, flags);
 521
 522         return changed ? length : 0;
 523 }
 524
 525 /*-------------------------------------------------------------------------*/
 526
 527 static void
 528 ohci_hub_descriptor (
 529         struct ohci_hcd                 *ohci,
 530         struct usb_hub_descriptor       *desc
 531 ) {
 532         u32             rh = roothub_a (ohci);
 533         u16             temp;
 534
 535         desc->bDescriptorType = 0x29;
 536         desc->bPwrOn2PwrGood = (rh & RH_A_POTPGT) >> 24;
 537         desc->bHubContrCurrent = 0;
 538
 539         desc->bNbrPorts = ohci->num_ports;
 540         temp = 1 + (ohci->num_ports / 8);
 541         desc->bDescLength = 7 + 2 * temp;
 542
 543         temp = 0;
 544         if (rh & RH_A_NPS)              /* no power switching? */
 545             temp |= 0x0002;
 546         if (rh & RH_A_PSM)              /* per-port power switching? */
 547             temp |= 0x0001;
 548         if (rh & RH_A_NOCP)             /* no overcurrent reporting? */
 549             temp |= 0x0010;
 550         else if (rh & RH_A_OCPM)        /* per-port overcurrent reporting? */
 551             temp |= 0x0008;
 552         desc->wHubCharacteristics = (__force __u16)cpu_to_hc16(ohci, temp);
 553
 554         /* ports removable, and usb 1.0 legacy PortPwrCtrlMask */
 555         rh = roothub_b (ohci);
 556         memset(desc->u.hs.DeviceRemovable, 0xff,
 557                         sizeof(desc->u.hs.DeviceRemovable));
 558         desc->u.hs.DeviceRemovable[0] = rh & RH_B_DR;
 559         if (ohci->num_ports > 7) {
 560                 desc->u.hs.DeviceRemovable[1] = (rh & RH_B_DR) >> 8;
 561                 desc->u.hs.DeviceRemovable[2] = 0xff;
 562         } else
 563                 desc->u.hs.DeviceRemovable[1] = 0xff;
 564 }
 565
 566 /*-------------------------------------------------------------------------*/
 567
 568 #ifdef  CONFIG_USB_OTG
 569
 570 static int ohci_start_port_reset (struct usb_hcd *hcd, unsigned port)
 571 {
 572         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
 573         u32                     status;
 574
 575         if (!port)
 576                 return -EINVAL;
 577         port--;
 578
 579         /* start port reset before HNP protocol times out */
 580         status = ohci_readl(ohci, &ohci->regs->roothub.portstatus [port]);
 581         if (!(status & RH_PS_CCS))
 582                 return -ENODEV;
 583
 584         /* khubd will finish the reset later */
 585         ohci_writel(ohci, RH_PS_PRS, &ohci->regs->roothub.portstatus [port]);
 586         return 0;
 587 }
 588
 589 #else
 590
 591 #define ohci_start_port_reset           NULL
 592
 593 #endif
 594
 595 /*-------------------------------------------------------------------------*/
 596
 597
 598 /* See usb 7.1.7.5:  root hubs must issue at least 50 msec reset signaling,
 599  * not necessarily continuous ... to guard against resume signaling.
 600  */
 601 #define PORT_RESET_MSEC         50
 602
 603 /* this timer value might be vendor-specific ... */
 604 #define PORT_RESET_HW_MSEC      10
 605
 606 /* wrap-aware logic morphed from <linux/jiffies.h> */
 607 #define tick_before(t1,t2) ((s16)(((s16)(t1))-((s16)(t2))) < 0)
 608
 609 /* called from some task, normally khubd */
 610 static inline int root_port_reset (struct ohci_hcd *ohci, unsigned port)
 611 {
 612         __hc32 __iomem *portstat = &ohci->regs->roothub.portstatus [port];
 613         u32     temp = 0;
 614         u16     now = ohci_readl(ohci, &ohci->regs->fmnumber);
 615         u16     reset_done = now + PORT_RESET_MSEC;
 616         int     limit_1 = DIV_ROUND_UP(PORT_RESET_MSEC, PORT_RESET_HW_MSEC);
 617
 618         /* build a "continuous enough" reset signal, with up to
 619          * 3msec gap between pulses.  scheduler HZ==100 must work;
 620          * this might need to be deadline-scheduled.
 621          */
 622         do {
 623                 int limit_2;
 624
 625                 /* spin until any current reset finishes */
 626                 limit_2 = PORT_RESET_HW_MSEC * 2;
 627                 while (--limit_2 >= 0) {
 628                         temp = ohci_readl (ohci, portstat);
 629                         /* handle e.g. CardBus eject */
 630                         if (temp == ~(u32)0)
 631                                 return -ESHUTDOWN;
 632                         if (!(temp & RH_PS_PRS))
 633                                 break;
 634                         udelay (500);
 635                 }
 636
 637                 /* timeout (a hardware error) has been observed when
 638                  * EHCI sets CF while this driver is resetting a port;
 639                  * presumably other disconnect paths might do it too.
 640                  */
 641                 if (limit_2 < 0) {
 642                         ohci_dbg(ohci,
 643                                 "port[%d] reset timeout, stat %08x\n",
 644                                 port, temp);
 645                         break;
 646                 }
 647
 648                 if (!(temp & RH_PS_CCS))
 649                         break;
 650                 if (temp & RH_PS_PRSC)
 651                         ohci_writel (ohci, RH_PS_PRSC, portstat);
 652
 653                 /* start the next reset, sleep till it's probably done */
 654                 ohci_writel (ohci, RH_PS_PRS, portstat);
 655                 msleep(PORT_RESET_HW_MSEC);
 656                 now = ohci_readl(ohci, &ohci->regs->fmnumber);
 657         } while (tick_before(now, reset_done) && --limit_1 >= 0);
 658
 659         /* caller synchronizes using PRSC ... and handles PRS
 660          * still being set when this returns.
 661          */
 662
 663         return 0;
 664 }
 665
 666 static int ohci_hub_control (
 667         struct usb_hcd  *hcd,
 668         u16             typeReq,
 669         u16             wValue,
 670         u16             wIndex,
 671         char            *buf,
 672         u16             wLength
 673 ) {
 674         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
 675         int             ports = ohci->num_ports;
 676         u32             temp;
 677         int             retval = 0;
 678
 679         if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
 680                 return -ESHUTDOWN;
 681
 682         switch (typeReq) {
 683         case ClearHubFeature:
 684                 switch (wValue) {
 685                 case C_HUB_OVER_CURRENT:
 686                         ohci_writel (ohci, RH_HS_OCIC,
 687                                         &ohci->regs->roothub.status);
 688                 case C_HUB_LOCAL_POWER:
 689                         break;
 690                 default:
 691                         goto error;
 692                 }
 693                 break;
 694         case ClearPortFeature:
 695                 if (!wIndex || wIndex > ports)
 696                         goto error;
 697                 wIndex--;
 698
 699                 switch (wValue) {
 700                 case USB_PORT_FEAT_ENABLE:
 701                         temp = RH_PS_CCS;
 702                         break;
 703                 case USB_PORT_FEAT_C_ENABLE:
 704                         temp = RH_PS_PESC;
 705                         break;
 706                 case USB_PORT_FEAT_SUSPEND:
 707                         temp = RH_PS_POCI;
 708                         break;
 709                 case USB_PORT_FEAT_C_SUSPEND:
 710                         temp = RH_PS_PSSC;
 711                         break;
 712                 case USB_PORT_FEAT_POWER:
 713                         temp = RH_PS_LSDA;
 714                         break;
 715                 case USB_PORT_FEAT_C_CONNECTION:
 716                         temp = RH_PS_CSC;
 717                         break;
 718                 case USB_PORT_FEAT_C_OVER_CURRENT:
 719                         temp = RH_PS_OCIC;
 720                         break;
 721                 case USB_PORT_FEAT_C_RESET:
 722                         temp = RH_PS_PRSC;
 723                         break;
 724                 default:
 725                         goto error;
 726                 }
 727                 ohci_writel (ohci, temp,
 728                                 &ohci->regs->roothub.portstatus [wIndex]);
 729                 // ohci_readl (ohci, &ohci->regs->roothub.portstatus [wIndex]);
 730                 break;
 731         case GetHubDescriptor:
 732                 ohci_hub_descriptor (ohci, (struct usb_hub_descriptor *) buf);
 733                 break;
 734         case GetHubStatus:
 735                 temp = roothub_status (ohci) & ~(RH_HS_CRWE | RH_HS_DRWE);
 736                 put_unaligned_le32(temp, buf);
 737                 break;
 738         case GetPortStatus:
 739                 if (!wIndex || wIndex > ports)
 740                         goto error;
 741                 wIndex--;
 742                 temp = roothub_portstatus (ohci, wIndex);
 743                 put_unaligned_le32(temp, buf);
 744
 745 #ifndef OHCI_VERBOSE_DEBUG
 746         if (*(u16*)(buf+2))     /* only if wPortChange is interesting */
 747 #endif
 748                 dbg_port (ohci, "GetStatus", wIndex, temp);
 749                 break;
 750         case SetHubFeature:
 751                 switch (wValue) {
 752                 case C_HUB_OVER_CURRENT:
 753                         // FIXME:  this can be cleared, yes?
 754                 case C_HUB_LOCAL_POWER:
 755                         break;
 756                 default:
 757                         goto error;
 758                 }
 759                 break;
 760         case SetPortFeature:
 761                 if (!wIndex || wIndex > ports)
 762                         goto error;
 763                 wIndex--;
 764                 switch (wValue) {
 765                 case USB_PORT_FEAT_SUSPEND:
 766 #ifdef  CONFIG_USB_OTG
 767                         if (hcd->self.otg_port == (wIndex + 1)
 768                                         && hcd->self.b_hnp_enable)
 769                                 ohci->start_hnp(ohci);
 770                         else
 771 #endif
 772                         ohci_writel (ohci, RH_PS_PSS,
 773                                 &ohci->regs->roothub.portstatus [wIndex]);
 774                         break;
 775                 case USB_PORT_FEAT_POWER:
 776                         ohci_writel (ohci, RH_PS_PPS,
 777                                 &ohci->regs->roothub.portstatus [wIndex]);
 778                         break;
 779                 case USB_PORT_FEAT_RESET:
 780                         retval = root_port_reset (ohci, wIndex);
 781                         break;
 782                 default:
 783                         goto error;
 784                 }
 785                 break;
 786
 787         default:
 788 error:
 789                 /* "protocol stall" on error */
 790                 retval = -EPIPE;
 791         }
 792         return retval;
 793 }
 794