xref: /linux/drivers/usb/host/ohci-hub.c (revision 858259cf7d1c443c836a2022b78cb281f0a9b95e)
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 	ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
57 	switch (ohci->hc_control & OHCI_CTRL_HCFS) {
58 	case OHCI_USB_RESUME:
59 		ohci_dbg (ohci, "resume/suspend?\n");
60 		ohci->hc_control &= ~OHCI_CTRL_HCFS;
61 		ohci->hc_control |= OHCI_USB_RESET;
62 		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
63 		(void) ohci_readl (ohci, &ohci->regs->control);
64 		/* FALL THROUGH */
65 	case OHCI_USB_RESET:
66 		status = -EBUSY;
67 		ohci_dbg (ohci, "needs reinit!\n");
68 		goto done;
69 	case OHCI_USB_SUSPEND:
70 		ohci_dbg (ohci, "already suspended\n");
71 		goto done;
72 	}
73 	ohci_dbg (ohci, "suspend root hub\n");
74 
75 	/* First stop any processing */
76 	if (ohci->hc_control & OHCI_SCHED_ENABLES) {
77 		int		limit;
78 
79 		ohci->hc_control &= ~OHCI_SCHED_ENABLES;
80 		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
81 		ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
82 		ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrstatus);
83 
84 		/* sched disables take effect on the next frame,
85 		 * then the last WDH could take 6+ msec
86 		 */
87 		ohci_dbg (ohci, "stopping schedules ...\n");
88 		limit = 2000;
89 		while (limit > 0) {
90 			udelay (250);
91 			limit =- 250;
92 			if (ohci_readl (ohci, &ohci->regs->intrstatus)
93 					& OHCI_INTR_SF)
94 				break;
95 		}
96 		dl_done_list (ohci, NULL);
97 		mdelay (7);
98 	}
99 	dl_done_list (ohci, NULL);
100 	finish_unlinks (ohci, ohci_frame_no(ohci), NULL);
101 	ohci_writel (ohci, ohci_readl (ohci, &ohci->regs->intrstatus),
102 			&ohci->regs->intrstatus);
103 
104 	/* maybe resume can wake root hub */
105 	if (hcd->remote_wakeup)
106 		ohci->hc_control |= OHCI_CTRL_RWE;
107 	else
108 		ohci->hc_control &= ~OHCI_CTRL_RWE;
109 
110 	/* Suspend hub ... this is the "global (to this bus) suspend" mode,
111 	 * which doesn't imply ports will first be individually suspended.
112 	 */
113 	ohci->hc_control &= ~OHCI_CTRL_HCFS;
114 	ohci->hc_control |= OHCI_USB_SUSPEND;
115 	ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
116 	(void) ohci_readl (ohci, &ohci->regs->control);
117 
118 	/* no resumes until devices finish suspending */
119 	ohci->next_statechange = jiffies + msecs_to_jiffies (5);
120 
121 done:
122 	/* external suspend vs self autosuspend ... same effect */
123 	if (status == 0)
124 		usb_hcd_suspend_root_hub(hcd);
125 	spin_unlock_irqrestore (&ohci->lock, flags);
126 	return status;
127 }
128 
129 static inline struct ed *find_head (struct ed *ed)
130 {
131 	/* for bulk and control lists */
132 	while (ed->ed_prev)
133 		ed = ed->ed_prev;
134 	return ed;
135 }
136 
137 /* caller has locked the root hub */
138 static int ohci_bus_resume (struct usb_hcd *hcd)
139 {
140 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
141 	u32			temp, enables;
142 	int			status = -EINPROGRESS;
143 
144 	if (time_before (jiffies, ohci->next_statechange))
145 		msleep(5);
146 
147 	spin_lock_irq (&ohci->lock);
148 	ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
149 
150 	if (ohci->hc_control & (OHCI_CTRL_IR | OHCI_SCHED_ENABLES)) {
151 		/* this can happen after resuming a swsusp snapshot */
152 		if (hcd->state == HC_STATE_RESUMING) {
153 			ohci_dbg (ohci, "BIOS/SMM active, control %03x\n",
154 					ohci->hc_control);
155 			status = -EBUSY;
156 		/* this happens when pmcore resumes HC then root */
157 		} else {
158 			ohci_dbg (ohci, "duplicate resume\n");
159 			status = 0;
160 		}
161 	} else switch (ohci->hc_control & OHCI_CTRL_HCFS) {
162 	case OHCI_USB_SUSPEND:
163 		ohci->hc_control &= ~(OHCI_CTRL_HCFS|OHCI_SCHED_ENABLES);
164 		ohci->hc_control |= OHCI_USB_RESUME;
165 		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
166 		(void) ohci_readl (ohci, &ohci->regs->control);
167 		ohci_dbg (ohci, "resume root hub\n");
168 		break;
169 	case OHCI_USB_RESUME:
170 		/* HCFS changes sometime after INTR_RD */
171 		ohci_info (ohci, "wakeup\n");
172 		break;
173 	case OHCI_USB_OPER:
174 		/* this can happen after resuming a swsusp snapshot */
175 		ohci_dbg (ohci, "snapshot resume? reinit\n");
176 		status = -EBUSY;
177 		break;
178 	default:		/* RESET, we lost power */
179 		ohci_dbg (ohci, "lost power\n");
180 		status = -EBUSY;
181 	}
182 	spin_unlock_irq (&ohci->lock);
183 	if (status == -EBUSY) {
184 		(void) ohci_init (ohci);
185 		return ohci_restart (ohci);
186 	}
187 	if (status != -EINPROGRESS)
188 		return status;
189 
190 	temp = ohci->num_ports;
191 	enables = 0;
192 	while (temp--) {
193 		u32 stat = ohci_readl (ohci,
194 				       &ohci->regs->roothub.portstatus [temp]);
195 
196 		/* force global, not selective, resume */
197 		if (!(stat & RH_PS_PSS))
198 			continue;
199 		ohci_writel (ohci, RH_PS_POCI,
200 				&ohci->regs->roothub.portstatus [temp]);
201 	}
202 
203 	/* Some controllers (lucent erratum) need extra-long delays */
204 	msleep (20 /* usb 11.5.1.10 */ + 12 /* 32 msec counter */ + 1);
205 
206 	temp = ohci_readl (ohci, &ohci->regs->control);
207 	temp &= OHCI_CTRL_HCFS;
208 	if (temp != OHCI_USB_RESUME) {
209 		ohci_err (ohci, "controller won't resume\n");
210 		return -EBUSY;
211 	}
212 
213 	/* disable old schedule state, reinit from scratch */
214 	ohci_writel (ohci, 0, &ohci->regs->ed_controlhead);
215 	ohci_writel (ohci, 0, &ohci->regs->ed_controlcurrent);
216 	ohci_writel (ohci, 0, &ohci->regs->ed_bulkhead);
217 	ohci_writel (ohci, 0, &ohci->regs->ed_bulkcurrent);
218 	ohci_writel (ohci, 0, &ohci->regs->ed_periodcurrent);
219 	ohci_writel (ohci, (u32) ohci->hcca_dma, &ohci->regs->hcca);
220 
221 	/* Sometimes PCI D3 suspend trashes frame timings ... */
222 	periodic_reinit (ohci);
223 
224 	/* interrupts might have been disabled */
225 	ohci_writel (ohci, OHCI_INTR_INIT, &ohci->regs->intrenable);
226 	if (ohci->ed_rm_list)
227 		ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrenable);
228 	ohci_writel (ohci, ohci_readl (ohci, &ohci->regs->intrstatus),
229 			&ohci->regs->intrstatus);
230 
231 	/* Then re-enable operations */
232 	ohci_writel (ohci, OHCI_USB_OPER, &ohci->regs->control);
233 	(void) ohci_readl (ohci, &ohci->regs->control);
234 	msleep (3);
235 
236 	temp = OHCI_CONTROL_INIT | OHCI_USB_OPER;
237 	if (hcd->can_wakeup)
238 		temp |= OHCI_CTRL_RWC;
239 	ohci->hc_control = temp;
240 	ohci_writel (ohci, temp, &ohci->regs->control);
241 	(void) ohci_readl (ohci, &ohci->regs->control);
242 
243 	/* TRSMRCY */
244 	msleep (10);
245 
246 	/* keep it alive for ~5x suspend + resume costs */
247 	ohci->next_statechange = jiffies + msecs_to_jiffies (250);
248 
249 	/* maybe turn schedules back on */
250 	enables = 0;
251 	temp = 0;
252 	if (!ohci->ed_rm_list) {
253 		if (ohci->ed_controltail) {
254 			ohci_writel (ohci,
255 					find_head (ohci->ed_controltail)->dma,
256 					&ohci->regs->ed_controlhead);
257 			enables |= OHCI_CTRL_CLE;
258 			temp |= OHCI_CLF;
259 		}
260 		if (ohci->ed_bulktail) {
261 			ohci_writel (ohci, find_head (ohci->ed_bulktail)->dma,
262 				&ohci->regs->ed_bulkhead);
263 			enables |= OHCI_CTRL_BLE;
264 			temp |= OHCI_BLF;
265 		}
266 	}
267 	if (hcd->self.bandwidth_isoc_reqs || hcd->self.bandwidth_int_reqs)
268 		enables |= OHCI_CTRL_PLE|OHCI_CTRL_IE;
269 	if (enables) {
270 		ohci_dbg (ohci, "restarting schedules ... %08x\n", enables);
271 		ohci->hc_control |= enables;
272 		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
273 		if (temp)
274 			ohci_writel (ohci, temp, &ohci->regs->cmdstatus);
275 		(void) ohci_readl (ohci, &ohci->regs->control);
276 	}
277 
278 	return 0;
279 }
280 
281 #endif	/* CONFIG_PM */
282 
283 /*-------------------------------------------------------------------------*/
284 
285 /* build "status change" packet (one or two bytes) from HC registers */
286 
287 static int
288 ohci_hub_status_data (struct usb_hcd *hcd, char *buf)
289 {
290 	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
291 	int		i, changed = 0, length = 1;
292 	int		can_suspend = hcd->can_wakeup;
293 	unsigned long	flags;
294 
295 	spin_lock_irqsave (&ohci->lock, flags);
296 
297 	/* handle autosuspended root:  finish resuming before
298 	 * letting khubd or root hub timer see state changes.
299 	 */
300 	if ((ohci->hc_control & OHCI_CTRL_HCFS) != OHCI_USB_OPER
301 			|| !HC_IS_RUNNING(hcd->state)) {
302 		can_suspend = 0;
303 		goto done;
304 	}
305 
306 	/* undocumented erratum seen on at least rev D */
307 	if ((ohci->flags & OHCI_QUIRK_AMD756)
308 			&& (roothub_a (ohci) & RH_A_NDP) > MAX_ROOT_PORTS) {
309 		ohci_warn (ohci, "bogus NDP, rereads as NDP=%d\n",
310 			  ohci_readl (ohci, &ohci->regs->roothub.a) & RH_A_NDP);
311 		/* retry later; "should not happen" */
312 		goto done;
313 	}
314 
315 	/* init status */
316 	if (roothub_status (ohci) & (RH_HS_LPSC | RH_HS_OCIC))
317 		buf [0] = changed = 1;
318 	else
319 		buf [0] = 0;
320 	if (ohci->num_ports > 7) {
321 		buf [1] = 0;
322 		length++;
323 	}
324 
325 	/* look at each port */
326 	for (i = 0; i < ohci->num_ports; i++) {
327 		u32	status = roothub_portstatus (ohci, i);
328 
329 		if (status & (RH_PS_CSC | RH_PS_PESC | RH_PS_PSSC
330 				| RH_PS_OCIC | RH_PS_PRSC)) {
331 			changed = 1;
332 			if (i < 7)
333 			    buf [0] |= 1 << (i + 1);
334 			else
335 			    buf [1] |= 1 << (i - 7);
336 			continue;
337 		}
338 
339 		/* can suspend if no ports are enabled; or if all all
340 		 * enabled ports are suspended AND remote wakeup is on.
341 		 */
342 		if (!(status & RH_PS_CCS))
343 			continue;
344 		if ((status & RH_PS_PSS) && hcd->remote_wakeup)
345 			continue;
346 		can_suspend = 0;
347 	}
348 done:
349 	spin_unlock_irqrestore (&ohci->lock, flags);
350 
351 #ifdef CONFIG_PM
352 	/* save power by suspending idle root hubs;
353 	 * INTR_RD wakes us when there's work
354 	 */
355 	if (can_suspend
356 			&& !changed
357 			&& !ohci->ed_rm_list
358 			&& ((OHCI_CTRL_HCFS | OHCI_SCHED_ENABLES)
359 					& ohci->hc_control)
360 				== OHCI_USB_OPER
361 			&& time_after (jiffies, ohci->next_statechange)
362 			&& usb_trylock_device (hcd->self.root_hub)
363 			) {
364 		ohci_vdbg (ohci, "autosuspend\n");
365 		(void) ohci_bus_suspend (hcd);
366 		usb_unlock_device (hcd->self.root_hub);
367 	}
368 #endif
369 
370 	return changed ? length : 0;
371 }
372 
373 /*-------------------------------------------------------------------------*/
374 
375 static void
376 ohci_hub_descriptor (
377 	struct ohci_hcd			*ohci,
378 	struct usb_hub_descriptor	*desc
379 ) {
380 	u32		rh = roothub_a (ohci);
381 	u16		temp;
382 
383 	desc->bDescriptorType = 0x29;
384 	desc->bPwrOn2PwrGood = (rh & RH_A_POTPGT) >> 24;
385 	desc->bHubContrCurrent = 0;
386 
387 	desc->bNbrPorts = ohci->num_ports;
388 	temp = 1 + (ohci->num_ports / 8);
389 	desc->bDescLength = 7 + 2 * temp;
390 
391 	temp = 0;
392 	if (rh & RH_A_NPS)		/* no power switching? */
393 	    temp |= 0x0002;
394 	if (rh & RH_A_PSM) 		/* per-port power switching? */
395 	    temp |= 0x0001;
396 	if (rh & RH_A_NOCP)		/* no overcurrent reporting? */
397 	    temp |= 0x0010;
398 	else if (rh & RH_A_OCPM)	/* per-port overcurrent reporting? */
399 	    temp |= 0x0008;
400 	desc->wHubCharacteristics = (__force __u16)cpu_to_hc16(ohci, temp);
401 
402 	/* two bitmaps:  ports removable, and usb 1.0 legacy PortPwrCtrlMask */
403 	rh = roothub_b (ohci);
404 	memset(desc->bitmap, 0xff, sizeof(desc->bitmap));
405 	desc->bitmap [0] = rh & RH_B_DR;
406 	if (ohci->num_ports > 7) {
407 		desc->bitmap [1] = (rh & RH_B_DR) >> 8;
408 		desc->bitmap [2] = 0xff;
409 	} else
410 		desc->bitmap [1] = 0xff;
411 }
412 
413 /*-------------------------------------------------------------------------*/
414 
415 #ifdef	CONFIG_USB_OTG
416 
417 static int ohci_start_port_reset (struct usb_hcd *hcd, unsigned port)
418 {
419 	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
420 	u32			status;
421 
422 	if (!port)
423 		return -EINVAL;
424 	port--;
425 
426 	/* start port reset before HNP protocol times out */
427 	status = ohci_readl(ohci, &ohci->regs->roothub.portstatus [port]);
428 	if (!(status & RH_PS_CCS))
429 		return -ENODEV;
430 
431 	/* khubd will finish the reset later */
432 	ohci_writel(ohci, RH_PS_PRS, &ohci->regs->roothub.portstatus [port]);
433 	return 0;
434 }
435 
436 static void start_hnp(struct ohci_hcd *ohci);
437 
438 #else
439 
440 #define	ohci_start_port_reset		NULL
441 
442 #endif
443 
444 /*-------------------------------------------------------------------------*/
445 
446 
447 /* See usb 7.1.7.5:  root hubs must issue at least 50 msec reset signaling,
448  * not necessarily continuous ... to guard against resume signaling.
449  * The short timeout is safe for non-root hubs, and is backward-compatible
450  * with earlier Linux hosts.
451  */
452 #ifdef	CONFIG_USB_SUSPEND
453 #define	PORT_RESET_MSEC		50
454 #else
455 #define	PORT_RESET_MSEC		10
456 #endif
457 
458 /* this timer value might be vendor-specific ... */
459 #define	PORT_RESET_HW_MSEC	10
460 
461 /* wrap-aware logic morphed from <linux/jiffies.h> */
462 #define tick_before(t1,t2) ((s16)(((s16)(t1))-((s16)(t2))) < 0)
463 
464 /* called from some task, normally khubd */
465 static inline void root_port_reset (struct ohci_hcd *ohci, unsigned port)
466 {
467 	__hc32 __iomem *portstat = &ohci->regs->roothub.portstatus [port];
468 	u32	temp;
469 	u16	now = ohci_readl(ohci, &ohci->regs->fmnumber);
470 	u16	reset_done = now + PORT_RESET_MSEC;
471 
472 	/* build a "continuous enough" reset signal, with up to
473 	 * 3msec gap between pulses.  scheduler HZ==100 must work;
474 	 * this might need to be deadline-scheduled.
475 	 */
476 	do {
477 		/* spin until any current reset finishes */
478 		for (;;) {
479 			temp = ohci_readl (ohci, portstat);
480 			if (!(temp & RH_PS_PRS))
481 				break;
482 			udelay (500);
483 		}
484 
485 		if (!(temp & RH_PS_CCS))
486 			break;
487 		if (temp & RH_PS_PRSC)
488 			ohci_writel (ohci, RH_PS_PRSC, portstat);
489 
490 		/* start the next reset, sleep till it's probably done */
491 		ohci_writel (ohci, RH_PS_PRS, portstat);
492 		msleep(PORT_RESET_HW_MSEC);
493 		now = ohci_readl(ohci, &ohci->regs->fmnumber);
494 	} while (tick_before(now, reset_done));
495 	/* caller synchronizes using PRSC */
496 }
497 
498 static int ohci_hub_control (
499 	struct usb_hcd	*hcd,
500 	u16		typeReq,
501 	u16		wValue,
502 	u16		wIndex,
503 	char		*buf,
504 	u16		wLength
505 ) {
506 	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
507 	int		ports = hcd_to_bus (hcd)->root_hub->maxchild;
508 	u32		temp;
509 	int		retval = 0;
510 
511 	switch (typeReq) {
512 	case ClearHubFeature:
513 		switch (wValue) {
514 		case C_HUB_OVER_CURRENT:
515 			ohci_writel (ohci, RH_HS_OCIC,
516 					&ohci->regs->roothub.status);
517 		case C_HUB_LOCAL_POWER:
518 			break;
519 		default:
520 			goto error;
521 		}
522 		break;
523 	case ClearPortFeature:
524 		if (!wIndex || wIndex > ports)
525 			goto error;
526 		wIndex--;
527 
528 		switch (wValue) {
529 		case USB_PORT_FEAT_ENABLE:
530 			temp = RH_PS_CCS;
531 			break;
532 		case USB_PORT_FEAT_C_ENABLE:
533 			temp = RH_PS_PESC;
534 			break;
535 		case USB_PORT_FEAT_SUSPEND:
536 			temp = RH_PS_POCI;
537 			if ((ohci->hc_control & OHCI_CTRL_HCFS)
538 					!= OHCI_USB_OPER)
539 				usb_hcd_resume_root_hub(hcd);
540 			break;
541 		case USB_PORT_FEAT_C_SUSPEND:
542 			temp = RH_PS_PSSC;
543 			break;
544 		case USB_PORT_FEAT_POWER:
545 			temp = RH_PS_LSDA;
546 			break;
547 		case USB_PORT_FEAT_C_CONNECTION:
548 			temp = RH_PS_CSC;
549 			break;
550 		case USB_PORT_FEAT_C_OVER_CURRENT:
551 			temp = RH_PS_OCIC;
552 			break;
553 		case USB_PORT_FEAT_C_RESET:
554 			temp = RH_PS_PRSC;
555 			break;
556 		default:
557 			goto error;
558 		}
559 		ohci_writel (ohci, temp,
560 				&ohci->regs->roothub.portstatus [wIndex]);
561 		// ohci_readl (ohci, &ohci->regs->roothub.portstatus [wIndex]);
562 		break;
563 	case GetHubDescriptor:
564 		ohci_hub_descriptor (ohci, (struct usb_hub_descriptor *) buf);
565 		break;
566 	case GetHubStatus:
567 		temp = roothub_status (ohci) & ~(RH_HS_CRWE | RH_HS_DRWE);
568 		*(__le32 *) buf = cpu_to_le32 (temp);
569 		break;
570 	case GetPortStatus:
571 		if (!wIndex || wIndex > ports)
572 			goto error;
573 		wIndex--;
574 		temp = roothub_portstatus (ohci, wIndex);
575 		*(__le32 *) buf = cpu_to_le32 (temp);
576 
577 #ifndef	OHCI_VERBOSE_DEBUG
578 	if (*(u16*)(buf+2))	/* only if wPortChange is interesting */
579 #endif
580 		dbg_port (ohci, "GetStatus", wIndex, temp);
581 		break;
582 	case SetHubFeature:
583 		switch (wValue) {
584 		case C_HUB_OVER_CURRENT:
585 			// FIXME:  this can be cleared, yes?
586 		case C_HUB_LOCAL_POWER:
587 			break;
588 		default:
589 			goto error;
590 		}
591 		break;
592 	case SetPortFeature:
593 		if (!wIndex || wIndex > ports)
594 			goto error;
595 		wIndex--;
596 		switch (wValue) {
597 		case USB_PORT_FEAT_SUSPEND:
598 #ifdef	CONFIG_USB_OTG
599 			if (hcd->self.otg_port == (wIndex + 1)
600 					&& hcd->self.b_hnp_enable)
601 				start_hnp(ohci);
602 			else
603 #endif
604 			ohci_writel (ohci, RH_PS_PSS,
605 				&ohci->regs->roothub.portstatus [wIndex]);
606 			break;
607 		case USB_PORT_FEAT_POWER:
608 			ohci_writel (ohci, RH_PS_PPS,
609 				&ohci->regs->roothub.portstatus [wIndex]);
610 			break;
611 		case USB_PORT_FEAT_RESET:
612 			root_port_reset (ohci, wIndex);
613 			break;
614 		default:
615 			goto error;
616 		}
617 		break;
618 
619 	default:
620 error:
621 		/* "protocol stall" on error */
622 		retval = -EPIPE;
623 	}
624 	return retval;
625 }
626 
627