[PATCH] USB: Fix USB suspend/resume crasher (#2)
[linux-2.6.git] / 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 #ifdef  CONFIG_PM
40
41 #define OHCI_SCHED_ENABLES \
42         (OHCI_CTRL_CLE|OHCI_CTRL_BLE|OHCI_CTRL_PLE|OHCI_CTRL_IE)
43
44 static void dl_done_list (struct ohci_hcd *, struct pt_regs *);
45 static void finish_unlinks (struct ohci_hcd *, u16 , struct pt_regs *);
46 static int ohci_restart (struct ohci_hcd *ohci);
47
48 static int ohci_bus_suspend (struct usb_hcd *hcd)
49 {
50         struct ohci_hcd         *ohci = hcd_to_ohci (hcd);
51         int                     status = 0;
52         unsigned long           flags;
53
54         spin_lock_irqsave (&ohci->lock, flags);
55
56         if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags))) {
57                 spin_unlock_irqrestore (&ohci->lock, flags);
58                 return -ESHUTDOWN;
59         }
60
61         ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
62         switch (ohci->hc_control & OHCI_CTRL_HCFS) {
63         case OHCI_USB_RESUME:
64                 ohci_dbg (ohci, "resume/suspend?\n");
65                 ohci->hc_control &= ~OHCI_CTRL_HCFS;
66                 ohci->hc_control |= OHCI_USB_RESET;
67                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
68                 (void) ohci_readl (ohci, &ohci->regs->control);
69                 /* FALL THROUGH */
70         case OHCI_USB_RESET:
71                 status = -EBUSY;
72                 ohci_dbg (ohci, "needs reinit!\n");
73                 goto done;
74         case OHCI_USB_SUSPEND:
75                 ohci_dbg (ohci, "already suspended\n");
76                 goto done;
77         }
78         ohci_dbg (ohci, "suspend root hub\n");
79
80         /* First stop any processing */
81         if (ohci->hc_control & OHCI_SCHED_ENABLES) {
82                 int             limit;
83
84                 ohci->hc_control &= ~OHCI_SCHED_ENABLES;
85                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
86                 ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
87                 ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrstatus);
88
89                 /* sched disables take effect on the next frame,
90                  * then the last WDH could take 6+ msec
91                  */
92                 ohci_dbg (ohci, "stopping schedules ...\n");
93                 limit = 2000;
94                 while (limit > 0) {
95                         udelay (250);
96                         limit =- 250;
97                         if (ohci_readl (ohci, &ohci->regs->intrstatus)
98                                         & OHCI_INTR_SF)
99                                 break;
100                 }
101                 dl_done_list (ohci, NULL);
102                 mdelay (7);
103         }
104         dl_done_list (ohci, NULL);
105         finish_unlinks (ohci, ohci_frame_no(ohci), NULL);
106         ohci_writel (ohci, ohci_readl (ohci, &ohci->regs->intrstatus),
107                         &ohci->regs->intrstatus);
108
109         /* maybe resume can wake root hub */
110         if (hcd->remote_wakeup)
111                 ohci->hc_control |= OHCI_CTRL_RWE;
112         else
113                 ohci->hc_control &= ~OHCI_CTRL_RWE;
114
115         /* Suspend hub ... this is the "global (to this bus) suspend" mode,
116          * which doesn't imply ports will first be individually suspended.
117          */
118         ohci->hc_control &= ~OHCI_CTRL_HCFS;
119         ohci->hc_control |= OHCI_USB_SUSPEND;
120         ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
121         (void) ohci_readl (ohci, &ohci->regs->control);
122
123         /* no resumes until devices finish suspending */
124         ohci->next_statechange = jiffies + msecs_to_jiffies (5);
125
126 done:
127         /* external suspend vs self autosuspend ... same effect */
128         if (status == 0)
129                 usb_hcd_suspend_root_hub(hcd);
130         spin_unlock_irqrestore (&ohci->lock, flags);
131         return status;
132 }
133
134 static inline struct ed *find_head (struct ed *ed)
135 {
136         /* for bulk and control lists */
137         while (ed->ed_prev)
138                 ed = ed->ed_prev;
139         return ed;
140 }
141
142 /* caller has locked the root hub */
143 static int ohci_bus_resume (struct usb_hcd *hcd)
144 {
145         struct ohci_hcd         *ohci = hcd_to_ohci (hcd);
146         u32                     temp, enables;
147         int                     status = -EINPROGRESS;
148         unsigned long           flags;
149
150         if (time_before (jiffies, ohci->next_statechange))
151                 msleep(5);
152
153         spin_lock_irqsave (&ohci->lock, flags);
154
155         if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags))) {
156                 spin_unlock_irqrestore (&ohci->lock, flags);
157                 return -ESHUTDOWN;
158         }
159
160
161         ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
162
163         if (ohci->hc_control & (OHCI_CTRL_IR | OHCI_SCHED_ENABLES)) {
164                 /* this can happen after resuming a swsusp snapshot */
165                 if (hcd->state == HC_STATE_RESUMING) {
166                         ohci_dbg (ohci, "BIOS/SMM active, control %03x\n",
167                                         ohci->hc_control);
168                         status = -EBUSY;
169                 /* this happens when pmcore resumes HC then root */
170                 } else {
171                         ohci_dbg (ohci, "duplicate resume\n");
172                         status = 0;
173                 }
174         } else switch (ohci->hc_control & OHCI_CTRL_HCFS) {
175         case OHCI_USB_SUSPEND:
176                 ohci->hc_control &= ~(OHCI_CTRL_HCFS|OHCI_SCHED_ENABLES);
177                 ohci->hc_control |= OHCI_USB_RESUME;
178                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
179                 (void) ohci_readl (ohci, &ohci->regs->control);
180                 ohci_dbg (ohci, "resume root hub\n");
181                 break;
182         case OHCI_USB_RESUME:
183                 /* HCFS changes sometime after INTR_RD */
184                 ohci_info (ohci, "wakeup\n");
185                 break;
186         case OHCI_USB_OPER:
187                 /* this can happen after resuming a swsusp snapshot */
188                 ohci_dbg (ohci, "snapshot resume? reinit\n");
189                 status = -EBUSY;
190                 break;
191         default:                /* RESET, we lost power */
192                 ohci_dbg (ohci, "lost power\n");
193                 status = -EBUSY;
194         }
195         spin_unlock_irqrestore (&ohci->lock, flags);
196         if (status == -EBUSY) {
197                 (void) ohci_init (ohci);
198                 return ohci_restart (ohci);
199         }
200         if (status != -EINPROGRESS)
201                 return status;
202
203         temp = ohci->num_ports;
204         enables = 0;
205         while (temp--) {
206                 u32 stat = ohci_readl (ohci,
207                                        &ohci->regs->roothub.portstatus [temp]);
208
209                 /* force global, not selective, resume */
210                 if (!(stat & RH_PS_PSS))
211                         continue;
212                 ohci_writel (ohci, RH_PS_POCI,
213                                 &ohci->regs->roothub.portstatus [temp]);
214         }
215
216         /* Some controllers (lucent erratum) need extra-long delays */
217         msleep (20 /* usb 11.5.1.10 */ + 12 /* 32 msec counter */ + 1);
218
219         temp = ohci_readl (ohci, &ohci->regs->control);
220         temp &= OHCI_CTRL_HCFS;
221         if (temp != OHCI_USB_RESUME) {
222                 ohci_err (ohci, "controller won't resume\n");
223                 return -EBUSY;
224         }
225
226         /* disable old schedule state, reinit from scratch */
227         ohci_writel (ohci, 0, &ohci->regs->ed_controlhead);
228         ohci_writel (ohci, 0, &ohci->regs->ed_controlcurrent);
229         ohci_writel (ohci, 0, &ohci->regs->ed_bulkhead);
230         ohci_writel (ohci, 0, &ohci->regs->ed_bulkcurrent);
231         ohci_writel (ohci, 0, &ohci->regs->ed_periodcurrent);
232         ohci_writel (ohci, (u32) ohci->hcca_dma, &ohci->regs->hcca);
233
234         /* Sometimes PCI D3 suspend trashes frame timings ... */
235         periodic_reinit (ohci);
236
237         /* interrupts might have been disabled */
238         ohci_writel (ohci, OHCI_INTR_INIT, &ohci->regs->intrenable);
239         if (ohci->ed_rm_list)
240                 ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrenable);
241         ohci_writel (ohci, ohci_readl (ohci, &ohci->regs->intrstatus),
242                         &ohci->regs->intrstatus);
243
244         /* Then re-enable operations */
245         ohci_writel (ohci, OHCI_USB_OPER, &ohci->regs->control);
246         (void) ohci_readl (ohci, &ohci->regs->control);
247         msleep (3);
248
249         temp = OHCI_CONTROL_INIT | OHCI_USB_OPER;
250         if (hcd->can_wakeup)
251                 temp |= OHCI_CTRL_RWC;
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         msleep (10);
258
259         /* keep it alive for ~5x suspend + resume costs */
260         ohci->next_statechange = jiffies + msecs_to_jiffies (250);
261
262         /* maybe turn schedules back on */
263         enables = 0;
264         temp = 0;
265         if (!ohci->ed_rm_list) {
266                 if (ohci->ed_controltail) {
267                         ohci_writel (ohci,
268                                         find_head (ohci->ed_controltail)->dma,
269                                         &ohci->regs->ed_controlhead);
270                         enables |= OHCI_CTRL_CLE;
271                         temp |= OHCI_CLF;
272                 }
273                 if (ohci->ed_bulktail) {
274                         ohci_writel (ohci, find_head (ohci->ed_bulktail)->dma,
275                                 &ohci->regs->ed_bulkhead);
276                         enables |= OHCI_CTRL_BLE;
277                         temp |= OHCI_BLF;
278                 }
279         }
280         if (hcd->self.bandwidth_isoc_reqs || hcd->self.bandwidth_int_reqs)
281                 enables |= OHCI_CTRL_PLE|OHCI_CTRL_IE;
282         if (enables) {
283                 ohci_dbg (ohci, "restarting schedules ... %08x\n", enables);
284                 ohci->hc_control |= enables;
285                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
286                 if (temp)
287                         ohci_writel (ohci, temp, &ohci->regs->cmdstatus);
288                 (void) ohci_readl (ohci, &ohci->regs->control);
289         }
290
291         return 0;
292 }
293
294 #endif  /* CONFIG_PM */
295
296 /*-------------------------------------------------------------------------*/
297
298 /* build "status change" packet (one or two bytes) from HC registers */
299
300 static int
301 ohci_hub_status_data (struct usb_hcd *hcd, char *buf)
302 {
303         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
304         int             i, changed = 0, length = 1;
305         int             can_suspend = hcd->can_wakeup;
306         unsigned long   flags;
307
308         spin_lock_irqsave (&ohci->lock, flags);
309
310         /* handle autosuspended root:  finish resuming before
311          * letting khubd or root hub timer see state changes.
312          */
313         if (unlikely((ohci->hc_control & OHCI_CTRL_HCFS) != OHCI_USB_OPER
314                      || !HC_IS_RUNNING(hcd->state))) {
315                 can_suspend = 0;
316                 goto done;
317         }
318
319         /* undocumented erratum seen on at least rev D */
320         if ((ohci->flags & OHCI_QUIRK_AMD756)
321                         && (roothub_a (ohci) & RH_A_NDP) > MAX_ROOT_PORTS) {
322                 ohci_warn (ohci, "bogus NDP, rereads as NDP=%d\n",
323                           ohci_readl (ohci, &ohci->regs->roothub.a) & RH_A_NDP);
324                 /* retry later; "should not happen" */
325                 goto done;
326         }
327
328         /* init status */
329         if (roothub_status (ohci) & (RH_HS_LPSC | RH_HS_OCIC))
330                 buf [0] = changed = 1;
331         else
332                 buf [0] = 0;
333         if (ohci->num_ports > 7) {
334                 buf [1] = 0;
335                 length++;
336         }
337
338         /* look at each port */
339         for (i = 0; i < ohci->num_ports; i++) {
340                 u32     status = roothub_portstatus (ohci, i);
341
342                 if (status & (RH_PS_CSC | RH_PS_PESC | RH_PS_PSSC
343                                 | RH_PS_OCIC | RH_PS_PRSC)) {
344                         changed = 1;
345                         if (i < 7)
346                             buf [0] |= 1 << (i + 1);
347                         else
348                             buf [1] |= 1 << (i - 7);
349                         continue;
350                 }
351
352                 /* can suspend if no ports are enabled; or if all all
353                  * enabled ports are suspended AND remote wakeup is on.
354                  */
355                 if (!(status & RH_PS_CCS))
356                         continue;
357                 if ((status & RH_PS_PSS) && hcd->remote_wakeup)
358                         continue;
359                 can_suspend = 0;
360         }
361 done:
362         spin_unlock_irqrestore (&ohci->lock, flags);
363
364 #ifdef CONFIG_PM
365         /* save power by suspending idle root hubs;
366          * INTR_RD wakes us when there's work
367          */
368         if (can_suspend
369                         && !changed
370                         && !ohci->ed_rm_list
371                         && ((OHCI_CTRL_HCFS | OHCI_SCHED_ENABLES)
372                                         & ohci->hc_control)
373                                 == OHCI_USB_OPER
374                         && time_after (jiffies, ohci->next_statechange)
375                         && usb_trylock_device (hcd->self.root_hub)
376                         ) {
377                 ohci_vdbg (ohci, "autosuspend\n");
378                 (void) ohci_bus_suspend (hcd);
379                 usb_unlock_device (hcd->self.root_hub);
380         }
381 #endif
382
383         return changed ? length : 0;
384 }
385
386 /*-------------------------------------------------------------------------*/
387
388 static void
389 ohci_hub_descriptor (
390         struct ohci_hcd                 *ohci,
391         struct usb_hub_descriptor       *desc
392 ) {
393         u32             rh = roothub_a (ohci);
394         u16             temp;
395
396         desc->bDescriptorType = 0x29;
397         desc->bPwrOn2PwrGood = (rh & RH_A_POTPGT) >> 24;
398         desc->bHubContrCurrent = 0;
399
400         desc->bNbrPorts = ohci->num_ports;
401         temp = 1 + (ohci->num_ports / 8);
402         desc->bDescLength = 7 + 2 * temp;
403
404         temp = 0;
405         if (rh & RH_A_NPS)              /* no power switching? */
406             temp |= 0x0002;
407         if (rh & RH_A_PSM)              /* per-port power switching? */
408             temp |= 0x0001;
409         if (rh & RH_A_NOCP)             /* no overcurrent reporting? */
410             temp |= 0x0010;
411         else if (rh & RH_A_OCPM)        /* per-port overcurrent reporting? */
412             temp |= 0x0008;
413         desc->wHubCharacteristics = (__force __u16)cpu_to_hc16(ohci, temp);
414
415         /* two bitmaps:  ports removable, and usb 1.0 legacy PortPwrCtrlMask */
416         rh = roothub_b (ohci);
417         memset(desc->bitmap, 0xff, sizeof(desc->bitmap));
418         desc->bitmap [0] = rh & RH_B_DR;
419         if (ohci->num_ports > 7) {
420                 desc->bitmap [1] = (rh & RH_B_DR) >> 8;
421                 desc->bitmap [2] = 0xff;
422         } else
423                 desc->bitmap [1] = 0xff;
424 }
425
426 /*-------------------------------------------------------------------------*/
427
428 #ifdef  CONFIG_USB_OTG
429
430 static int ohci_start_port_reset (struct usb_hcd *hcd, unsigned port)
431 {
432         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
433         u32                     status;
434
435         if (!port)
436                 return -EINVAL;
437         port--;
438
439         /* start port reset before HNP protocol times out */
440         status = ohci_readl(ohci, &ohci->regs->roothub.portstatus [port]);
441         if (!(status & RH_PS_CCS))
442                 return -ENODEV;
443
444         /* khubd will finish the reset later */
445         ohci_writel(ohci, RH_PS_PRS, &ohci->regs->roothub.portstatus [port]);
446         return 0;
447 }
448
449 static void start_hnp(struct ohci_hcd *ohci);
450
451 #else
452
453 #define ohci_start_port_reset           NULL
454
455 #endif
456
457 /*-------------------------------------------------------------------------*/
458
459
460 /* See usb 7.1.7.5:  root hubs must issue at least 50 msec reset signaling,
461  * not necessarily continuous ... to guard against resume signaling.
462  * The short timeout is safe for non-root hubs, and is backward-compatible
463  * with earlier Linux hosts.
464  */
465 #ifdef  CONFIG_USB_SUSPEND
466 #define PORT_RESET_MSEC         50
467 #else
468 #define PORT_RESET_MSEC         10
469 #endif
470
471 /* this timer value might be vendor-specific ... */
472 #define PORT_RESET_HW_MSEC      10
473
474 /* wrap-aware logic morphed from <linux/jiffies.h> */
475 #define tick_before(t1,t2) ((s16)(((s16)(t1))-((s16)(t2))) < 0)
476
477 /* called from some task, normally khubd */
478 static inline void root_port_reset (struct ohci_hcd *ohci, unsigned port)
479 {
480         __hc32 __iomem *portstat = &ohci->regs->roothub.portstatus [port];
481         u32     temp;
482         u16     now = ohci_readl(ohci, &ohci->regs->fmnumber);
483         u16     reset_done = now + PORT_RESET_MSEC;
484
485         /* build a "continuous enough" reset signal, with up to
486          * 3msec gap between pulses.  scheduler HZ==100 must work;
487          * this might need to be deadline-scheduled.
488          */
489         do {
490                 /* spin until any current reset finishes */
491                 for (;;) {
492                         temp = ohci_readl (ohci, portstat);
493                         if (!(temp & RH_PS_PRS))
494                                 break;
495                         udelay (500);
496                 } 
497
498                 if (!(temp & RH_PS_CCS))
499                         break;
500                 if (temp & RH_PS_PRSC)
501                         ohci_writel (ohci, RH_PS_PRSC, portstat);
502
503                 /* start the next reset, sleep till it's probably done */
504                 ohci_writel (ohci, RH_PS_PRS, portstat);
505                 msleep(PORT_RESET_HW_MSEC);
506                 now = ohci_readl(ohci, &ohci->regs->fmnumber);
507         } while (tick_before(now, reset_done));
508         /* caller synchronizes using PRSC */
509 }
510
511 static int ohci_hub_control (
512         struct usb_hcd  *hcd,
513         u16             typeReq,
514         u16             wValue,
515         u16             wIndex,
516         char            *buf,
517         u16             wLength
518 ) {
519         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
520         int             ports = hcd_to_bus (hcd)->root_hub->maxchild;
521         u32             temp;
522         int             retval = 0;
523
524         if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
525                 return -ESHUTDOWN;
526
527         switch (typeReq) {
528         case ClearHubFeature:
529                 switch (wValue) {
530                 case C_HUB_OVER_CURRENT:
531                         ohci_writel (ohci, RH_HS_OCIC,
532                                         &ohci->regs->roothub.status);
533                 case C_HUB_LOCAL_POWER:
534                         break;
535                 default:
536                         goto error;
537                 }
538                 break;
539         case ClearPortFeature:
540                 if (!wIndex || wIndex > ports)
541                         goto error;
542                 wIndex--;
543
544                 switch (wValue) {
545                 case USB_PORT_FEAT_ENABLE:
546                         temp = RH_PS_CCS;
547                         break;
548                 case USB_PORT_FEAT_C_ENABLE:
549                         temp = RH_PS_PESC;
550                         break;
551                 case USB_PORT_FEAT_SUSPEND:
552                         temp = RH_PS_POCI;
553                         if ((ohci->hc_control & OHCI_CTRL_HCFS)
554                                         != OHCI_USB_OPER)
555                                 usb_hcd_resume_root_hub(hcd);
556                         break;
557                 case USB_PORT_FEAT_C_SUSPEND:
558                         temp = RH_PS_PSSC;
559                         break;
560                 case USB_PORT_FEAT_POWER:
561                         temp = RH_PS_LSDA;
562                         break;
563                 case USB_PORT_FEAT_C_CONNECTION:
564                         temp = RH_PS_CSC;
565                         break;
566                 case USB_PORT_FEAT_C_OVER_CURRENT:
567                         temp = RH_PS_OCIC;
568                         break;
569                 case USB_PORT_FEAT_C_RESET:
570                         temp = RH_PS_PRSC;
571                         break;
572                 default:
573                         goto error;
574                 }
575                 ohci_writel (ohci, temp,
576                                 &ohci->regs->roothub.portstatus [wIndex]);
577                 // ohci_readl (ohci, &ohci->regs->roothub.portstatus [wIndex]);
578                 break;
579         case GetHubDescriptor:
580                 ohci_hub_descriptor (ohci, (struct usb_hub_descriptor *) buf);
581                 break;
582         case GetHubStatus:
583                 temp = roothub_status (ohci) & ~(RH_HS_CRWE | RH_HS_DRWE);
584                 *(__le32 *) buf = cpu_to_le32 (temp);
585                 break;
586         case GetPortStatus:
587                 if (!wIndex || wIndex > ports)
588                         goto error;
589                 wIndex--;
590                 temp = roothub_portstatus (ohci, wIndex);
591                 *(__le32 *) buf = cpu_to_le32 (temp);
592
593 #ifndef OHCI_VERBOSE_DEBUG
594         if (*(u16*)(buf+2))     /* only if wPortChange is interesting */
595 #endif
596                 dbg_port (ohci, "GetStatus", wIndex, temp);
597                 break;
598         case SetHubFeature:
599                 switch (wValue) {
600                 case C_HUB_OVER_CURRENT:
601                         // FIXME:  this can be cleared, yes?
602                 case C_HUB_LOCAL_POWER:
603                         break;
604                 default:
605                         goto error;
606                 }
607                 break;
608         case SetPortFeature:
609                 if (!wIndex || wIndex > ports)
610                         goto error;
611                 wIndex--;
612                 switch (wValue) {
613                 case USB_PORT_FEAT_SUSPEND:
614 #ifdef  CONFIG_USB_OTG
615                         if (hcd->self.otg_port == (wIndex + 1)
616                                         && hcd->self.b_hnp_enable)
617                                 start_hnp(ohci);
618                         else
619 #endif
620                         ohci_writel (ohci, RH_PS_PSS,
621                                 &ohci->regs->roothub.portstatus [wIndex]);
622                         break;
623                 case USB_PORT_FEAT_POWER:
624                         ohci_writel (ohci, RH_PS_PPS,
625                                 &ohci->regs->roothub.portstatus [wIndex]);
626                         break;
627                 case USB_PORT_FEAT_RESET:
628                         root_port_reset (ohci, wIndex);
629                         break;
630                 default:
631                         goto error;
632                 }
633                 break;
634
635         default:
636 error:
637                 /* "protocol stall" on error */
638                 retval = -EPIPE;
639         }
640         return retval;
641 }
642