xref: /openbmc/linux/drivers/usb/host/ohci-hub.c (revision 64c70b1c)
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 /* hcd->hub_irq_enable() */
40 static void ohci_rhsc_enable (struct usb_hcd *hcd)
41 {
42 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
43 
44 	spin_lock_irq(&ohci->lock);
45 	if (!ohci->autostop)
46 		del_timer(&hcd->rh_timer);	/* Prevent next poll */
47 	ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrenable);
48 	spin_unlock_irq(&ohci->lock);
49 }
50 
51 #define OHCI_SCHED_ENABLES \
52 	(OHCI_CTRL_CLE|OHCI_CTRL_BLE|OHCI_CTRL_PLE|OHCI_CTRL_IE)
53 
54 static void dl_done_list (struct ohci_hcd *);
55 static void finish_unlinks (struct ohci_hcd *, u16);
56 
57 #ifdef	CONFIG_PM
58 static int ohci_restart(struct ohci_hcd *ohci);
59 
60 static int ohci_rh_suspend (struct ohci_hcd *ohci, int autostop)
61 __releases(ohci->lock)
62 __acquires(ohci->lock)
63 {
64 	int			status = 0;
65 
66 	ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
67 	switch (ohci->hc_control & OHCI_CTRL_HCFS) {
68 	case OHCI_USB_RESUME:
69 		ohci_dbg (ohci, "resume/suspend?\n");
70 		ohci->hc_control &= ~OHCI_CTRL_HCFS;
71 		ohci->hc_control |= OHCI_USB_RESET;
72 		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
73 		(void) ohci_readl (ohci, &ohci->regs->control);
74 		/* FALL THROUGH */
75 	case OHCI_USB_RESET:
76 		status = -EBUSY;
77 		ohci_dbg (ohci, "needs reinit!\n");
78 		goto done;
79 	case OHCI_USB_SUSPEND:
80 		if (!ohci->autostop) {
81 			ohci_dbg (ohci, "already suspended\n");
82 			goto done;
83 		}
84 	}
85 	ohci_dbg (ohci, "%s root hub\n",
86 			autostop ? "auto-stop" : "suspend");
87 
88 	/* First stop any processing */
89 	if (!autostop && (ohci->hc_control & OHCI_SCHED_ENABLES)) {
90 		ohci->hc_control &= ~OHCI_SCHED_ENABLES;
91 		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
92 		ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
93 		ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrstatus);
94 
95 		/* sched disables take effect on the next frame,
96 		 * then the last WDH could take 6+ msec
97 		 */
98 		ohci_dbg (ohci, "stopping schedules ...\n");
99 		ohci->autostop = 0;
100 		spin_unlock_irq (&ohci->lock);
101 		msleep (8);
102 		spin_lock_irq (&ohci->lock);
103 	}
104 	dl_done_list (ohci);
105 	finish_unlinks (ohci, ohci_frame_no(ohci));
106 
107 	/* maybe resume can wake root hub */
108 	if (device_may_wakeup(&ohci_to_hcd(ohci)->self.root_hub->dev) ||
109 			autostop)
110 		ohci->hc_control |= OHCI_CTRL_RWE;
111 	else {
112 		ohci_writel (ohci, OHCI_INTR_RHSC, &ohci->regs->intrdisable);
113 		ohci->hc_control &= ~OHCI_CTRL_RWE;
114 	}
115 
116 	/* Suspend hub ... this is the "global (to this bus) suspend" mode,
117 	 * which doesn't imply ports will first be individually suspended.
118 	 */
119 	ohci->hc_control &= ~OHCI_CTRL_HCFS;
120 	ohci->hc_control |= OHCI_USB_SUSPEND;
121 	ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
122 	(void) ohci_readl (ohci, &ohci->regs->control);
123 
124 	/* no resumes until devices finish suspending */
125 	if (!autostop) {
126 		ohci->next_statechange = jiffies + msecs_to_jiffies (5);
127 		ohci->autostop = 0;
128 	}
129 
130 done:
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_rh_resume (struct ohci_hcd *ohci)
144 __releases(ohci->lock)
145 __acquires(ohci->lock)
146 {
147 	struct usb_hcd		*hcd = ohci_to_hcd (ohci);
148 	u32			temp, enables;
149 	int			status = -EINPROGRESS;
150 	int			autostopped = ohci->autostop;
151 
152 	ohci->autostop = 0;
153 	ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
154 
155 	if (ohci->hc_control & (OHCI_CTRL_IR | OHCI_SCHED_ENABLES)) {
156 		/* this can happen after resuming a swsusp snapshot */
157 		if (hcd->state == HC_STATE_RESUMING) {
158 			ohci_dbg (ohci, "BIOS/SMM active, control %03x\n",
159 					ohci->hc_control);
160 			status = -EBUSY;
161 		/* this happens when pmcore resumes HC then root */
162 		} else {
163 			ohci_dbg (ohci, "duplicate resume\n");
164 			status = 0;
165 		}
166 	} else switch (ohci->hc_control & OHCI_CTRL_HCFS) {
167 	case OHCI_USB_SUSPEND:
168 		ohci->hc_control &= ~(OHCI_CTRL_HCFS|OHCI_SCHED_ENABLES);
169 		ohci->hc_control |= OHCI_USB_RESUME;
170 		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
171 		(void) ohci_readl (ohci, &ohci->regs->control);
172 		ohci_dbg (ohci, "%s root hub\n",
173 				autostopped ? "auto-start" : "resume");
174 		break;
175 	case OHCI_USB_RESUME:
176 		/* HCFS changes sometime after INTR_RD */
177 		ohci_dbg(ohci, "%swakeup root hub\n",
178 				autostopped ? "auto-" : "");
179 		break;
180 	case OHCI_USB_OPER:
181 		/* this can happen after resuming a swsusp snapshot */
182 		ohci_dbg (ohci, "snapshot resume? reinit\n");
183 		status = -EBUSY;
184 		break;
185 	default:		/* RESET, we lost power */
186 		ohci_dbg (ohci, "lost power\n");
187 		status = -EBUSY;
188 	}
189 	if (status == -EBUSY) {
190 		if (!autostopped) {
191 			spin_unlock_irq (&ohci->lock);
192 			(void) ohci_init (ohci);
193 			status = ohci_restart (ohci);
194 			spin_lock_irq (&ohci->lock);
195 		}
196 		return status;
197 	}
198 	if (status != -EINPROGRESS)
199 		return status;
200 	if (autostopped)
201 		goto skip_resume;
202 	spin_unlock_irq (&ohci->lock);
203 
204 	/* Some controllers (lucent erratum) need extra-long delays */
205 	msleep (20 /* usb 11.5.1.10 */ + 12 /* 32 msec counter */ + 1);
206 
207 	temp = ohci_readl (ohci, &ohci->regs->control);
208 	temp &= OHCI_CTRL_HCFS;
209 	if (temp != OHCI_USB_RESUME) {
210 		ohci_err (ohci, "controller won't resume\n");
211 		spin_lock_irq(&ohci->lock);
212 		return -EBUSY;
213 	}
214 
215 	/* disable old schedule state, reinit from scratch */
216 	ohci_writel (ohci, 0, &ohci->regs->ed_controlhead);
217 	ohci_writel (ohci, 0, &ohci->regs->ed_controlcurrent);
218 	ohci_writel (ohci, 0, &ohci->regs->ed_bulkhead);
219 	ohci_writel (ohci, 0, &ohci->regs->ed_bulkcurrent);
220 	ohci_writel (ohci, 0, &ohci->regs->ed_periodcurrent);
221 	ohci_writel (ohci, (u32) ohci->hcca_dma, &ohci->regs->hcca);
222 
223 	/* Sometimes PCI D3 suspend trashes frame timings ... */
224 	periodic_reinit (ohci);
225 
226 	/* the following code is executed with ohci->lock held and
227 	 * irqs disabled if and only if autostopped is true
228 	 */
229 
230 skip_resume:
231 	/* interrupts might have been disabled */
232 	ohci_writel (ohci, OHCI_INTR_INIT, &ohci->regs->intrenable);
233 	if (ohci->ed_rm_list)
234 		ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrenable);
235 
236 	/* Then re-enable operations */
237 	ohci_writel (ohci, OHCI_USB_OPER, &ohci->regs->control);
238 	(void) ohci_readl (ohci, &ohci->regs->control);
239 	if (!autostopped)
240 		msleep (3);
241 
242 	temp = ohci->hc_control;
243 	temp &= OHCI_CTRL_RWC;
244 	temp |= OHCI_CONTROL_INIT | OHCI_USB_OPER;
245 	ohci->hc_control = temp;
246 	ohci_writel (ohci, temp, &ohci->regs->control);
247 	(void) ohci_readl (ohci, &ohci->regs->control);
248 
249 	/* TRSMRCY */
250 	if (!autostopped) {
251 		msleep (10);
252 		spin_lock_irq (&ohci->lock);
253 	}
254 	/* now ohci->lock is always held and irqs are always disabled */
255 
256 	/* keep it alive for more than ~5x suspend + resume costs */
257 	ohci->next_statechange = jiffies + STATECHANGE_DELAY;
258 
259 	/* maybe turn schedules back on */
260 	enables = 0;
261 	temp = 0;
262 	if (!ohci->ed_rm_list) {
263 		if (ohci->ed_controltail) {
264 			ohci_writel (ohci,
265 					find_head (ohci->ed_controltail)->dma,
266 					&ohci->regs->ed_controlhead);
267 			enables |= OHCI_CTRL_CLE;
268 			temp |= OHCI_CLF;
269 		}
270 		if (ohci->ed_bulktail) {
271 			ohci_writel (ohci, find_head (ohci->ed_bulktail)->dma,
272 				&ohci->regs->ed_bulkhead);
273 			enables |= OHCI_CTRL_BLE;
274 			temp |= OHCI_BLF;
275 		}
276 	}
277 	if (hcd->self.bandwidth_isoc_reqs || hcd->self.bandwidth_int_reqs)
278 		enables |= OHCI_CTRL_PLE|OHCI_CTRL_IE;
279 	if (enables) {
280 		ohci_dbg (ohci, "restarting schedules ... %08x\n", enables);
281 		ohci->hc_control |= enables;
282 		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
283 		if (temp)
284 			ohci_writel (ohci, temp, &ohci->regs->cmdstatus);
285 		(void) ohci_readl (ohci, &ohci->regs->control);
286 	}
287 
288 	return 0;
289 }
290 
291 static int ohci_bus_suspend (struct usb_hcd *hcd)
292 {
293 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
294 	int			rc;
295 
296 	spin_lock_irq (&ohci->lock);
297 
298 	if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
299 		rc = -ESHUTDOWN;
300 	else
301 		rc = ohci_rh_suspend (ohci, 0);
302 	spin_unlock_irq (&ohci->lock);
303 	return rc;
304 }
305 
306 static int ohci_bus_resume (struct usb_hcd *hcd)
307 {
308 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
309 	int			rc;
310 
311 	if (time_before (jiffies, ohci->next_statechange))
312 		msleep(5);
313 
314 	spin_lock_irq (&ohci->lock);
315 
316 	if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
317 		rc = -ESHUTDOWN;
318 	else
319 		rc = ohci_rh_resume (ohci);
320 	spin_unlock_irq (&ohci->lock);
321 
322 	/* poll until we know a device is connected or we autostop */
323 	if (rc == 0)
324 		usb_hcd_poll_rh_status(hcd);
325 	return rc;
326 }
327 
328 /* Carry out polling-, autostop-, and autoresume-related state changes */
329 static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
330 		int any_connected)
331 {
332 	int	poll_rh = 1;
333 
334 	switch (ohci->hc_control & OHCI_CTRL_HCFS) {
335 
336 	case OHCI_USB_OPER:
337 		/* keep on polling until we know a device is connected
338 		 * and RHSC is enabled */
339 		if (!ohci->autostop) {
340 			if (any_connected ||
341 					!device_may_wakeup(&ohci_to_hcd(ohci)
342 						->self.root_hub->dev)) {
343 				if (ohci_readl(ohci, &ohci->regs->intrenable) &
344 						OHCI_INTR_RHSC)
345 					poll_rh = 0;
346 			} else {
347 				ohci->autostop = 1;
348 				ohci->next_statechange = jiffies + HZ;
349 			}
350 
351 		/* if no devices have been attached for one second, autostop */
352 		} else {
353 			if (changed || any_connected) {
354 				ohci->autostop = 0;
355 				ohci->next_statechange = jiffies +
356 						STATECHANGE_DELAY;
357 			} else if (time_after_eq(jiffies,
358 						ohci->next_statechange)
359 					&& !ohci->ed_rm_list
360 					&& !(ohci->hc_control &
361 						OHCI_SCHED_ENABLES)) {
362 				ohci_rh_suspend(ohci, 1);
363 			}
364 		}
365 		break;
366 
367 	/* if there is a port change, autostart or ask to be resumed */
368 	case OHCI_USB_SUSPEND:
369 	case OHCI_USB_RESUME:
370 		if (changed) {
371 			if (ohci->autostop)
372 				ohci_rh_resume(ohci);
373 			else
374 				usb_hcd_resume_root_hub(ohci_to_hcd(ohci));
375 		} else {
376 			/* everything is idle, no need for polling */
377 			poll_rh = 0;
378 		}
379 		break;
380 	}
381 	return poll_rh;
382 }
383 
384 #else	/* CONFIG_PM */
385 
386 static inline int ohci_rh_resume(struct ohci_hcd *ohci)
387 {
388 	return 0;
389 }
390 
391 /* Carry out polling-related state changes.
392  * autostop isn't used when CONFIG_PM is turned off.
393  */
394 static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
395 		int any_connected)
396 {
397 	int	poll_rh = 1;
398 
399 	/* keep on polling until RHSC is enabled */
400 	if (ohci_readl(ohci, &ohci->regs->intrenable) & OHCI_INTR_RHSC)
401 		poll_rh = 0;
402 	return poll_rh;
403 }
404 
405 #endif	/* CONFIG_PM */
406 
407 /*-------------------------------------------------------------------------*/
408 
409 /* build "status change" packet (one or two bytes) from HC registers */
410 
411 static int
412 ohci_hub_status_data (struct usb_hcd *hcd, char *buf)
413 {
414 	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
415 	int		i, changed = 0, length = 1;
416 	int		any_connected = 0;
417 	unsigned long	flags;
418 
419 	spin_lock_irqsave (&ohci->lock, flags);
420 	if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags))
421 		goto done;
422 
423 	/* undocumented erratum seen on at least rev D */
424 	if ((ohci->flags & OHCI_QUIRK_AMD756)
425 			&& (roothub_a (ohci) & RH_A_NDP) > MAX_ROOT_PORTS) {
426 		ohci_warn (ohci, "bogus NDP, rereads as NDP=%d\n",
427 			  ohci_readl (ohci, &ohci->regs->roothub.a) & RH_A_NDP);
428 		/* retry later; "should not happen" */
429 		goto done;
430 	}
431 
432 	/* init status */
433 	if (roothub_status (ohci) & (RH_HS_LPSC | RH_HS_OCIC))
434 		buf [0] = changed = 1;
435 	else
436 		buf [0] = 0;
437 	if (ohci->num_ports > 7) {
438 		buf [1] = 0;
439 		length++;
440 	}
441 
442 	/* look at each port */
443 	for (i = 0; i < ohci->num_ports; i++) {
444 		u32	status = roothub_portstatus (ohci, i);
445 
446 		/* can't autostop if ports are connected */
447 		any_connected |= (status & RH_PS_CCS);
448 
449 		if (status & (RH_PS_CSC | RH_PS_PESC | RH_PS_PSSC
450 				| RH_PS_OCIC | RH_PS_PRSC)) {
451 			changed = 1;
452 			if (i < 7)
453 			    buf [0] |= 1 << (i + 1);
454 			else
455 			    buf [1] |= 1 << (i - 7);
456 		}
457 	}
458 
459 	hcd->poll_rh = ohci_root_hub_state_changes(ohci, changed,
460 			any_connected);
461 
462 done:
463 	spin_unlock_irqrestore (&ohci->lock, flags);
464 
465 	return changed ? length : 0;
466 }
467 
468 /*-------------------------------------------------------------------------*/
469 
470 static void
471 ohci_hub_descriptor (
472 	struct ohci_hcd			*ohci,
473 	struct usb_hub_descriptor	*desc
474 ) {
475 	u32		rh = roothub_a (ohci);
476 	u16		temp;
477 
478 	desc->bDescriptorType = 0x29;
479 	desc->bPwrOn2PwrGood = (rh & RH_A_POTPGT) >> 24;
480 	desc->bHubContrCurrent = 0;
481 
482 	desc->bNbrPorts = ohci->num_ports;
483 	temp = 1 + (ohci->num_ports / 8);
484 	desc->bDescLength = 7 + 2 * temp;
485 
486 	temp = 0;
487 	if (rh & RH_A_NPS)		/* no power switching? */
488 	    temp |= 0x0002;
489 	if (rh & RH_A_PSM)		/* per-port power switching? */
490 	    temp |= 0x0001;
491 	if (rh & RH_A_NOCP)		/* no overcurrent reporting? */
492 	    temp |= 0x0010;
493 	else if (rh & RH_A_OCPM)	/* per-port overcurrent reporting? */
494 	    temp |= 0x0008;
495 	desc->wHubCharacteristics = (__force __u16)cpu_to_hc16(ohci, temp);
496 
497 	/* two bitmaps:  ports removable, and usb 1.0 legacy PortPwrCtrlMask */
498 	rh = roothub_b (ohci);
499 	memset(desc->bitmap, 0xff, sizeof(desc->bitmap));
500 	desc->bitmap [0] = rh & RH_B_DR;
501 	if (ohci->num_ports > 7) {
502 		desc->bitmap [1] = (rh & RH_B_DR) >> 8;
503 		desc->bitmap [2] = 0xff;
504 	} else
505 		desc->bitmap [1] = 0xff;
506 }
507 
508 /*-------------------------------------------------------------------------*/
509 
510 #ifdef	CONFIG_USB_OTG
511 
512 static int ohci_start_port_reset (struct usb_hcd *hcd, unsigned port)
513 {
514 	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
515 	u32			status;
516 
517 	if (!port)
518 		return -EINVAL;
519 	port--;
520 
521 	/* start port reset before HNP protocol times out */
522 	status = ohci_readl(ohci, &ohci->regs->roothub.portstatus [port]);
523 	if (!(status & RH_PS_CCS))
524 		return -ENODEV;
525 
526 	/* khubd will finish the reset later */
527 	ohci_writel(ohci, RH_PS_PRS, &ohci->regs->roothub.portstatus [port]);
528 	return 0;
529 }
530 
531 static void start_hnp(struct ohci_hcd *ohci);
532 
533 #else
534 
535 #define	ohci_start_port_reset		NULL
536 
537 #endif
538 
539 /*-------------------------------------------------------------------------*/
540 
541 
542 /* See usb 7.1.7.5:  root hubs must issue at least 50 msec reset signaling,
543  * not necessarily continuous ... to guard against resume signaling.
544  * The short timeout is safe for non-root hubs, and is backward-compatible
545  * with earlier Linux hosts.
546  */
547 #ifdef	CONFIG_USB_SUSPEND
548 #define	PORT_RESET_MSEC		50
549 #else
550 #define	PORT_RESET_MSEC		10
551 #endif
552 
553 /* this timer value might be vendor-specific ... */
554 #define	PORT_RESET_HW_MSEC	10
555 
556 /* wrap-aware logic morphed from <linux/jiffies.h> */
557 #define tick_before(t1,t2) ((s16)(((s16)(t1))-((s16)(t2))) < 0)
558 
559 /* called from some task, normally khubd */
560 static inline int root_port_reset (struct ohci_hcd *ohci, unsigned port)
561 {
562 	__hc32 __iomem *portstat = &ohci->regs->roothub.portstatus [port];
563 	u32	temp;
564 	u16	now = ohci_readl(ohci, &ohci->regs->fmnumber);
565 	u16	reset_done = now + PORT_RESET_MSEC;
566 
567 	/* build a "continuous enough" reset signal, with up to
568 	 * 3msec gap between pulses.  scheduler HZ==100 must work;
569 	 * this might need to be deadline-scheduled.
570 	 */
571 	do {
572 		/* spin until any current reset finishes */
573 		for (;;) {
574 			temp = ohci_readl (ohci, portstat);
575 			/* handle e.g. CardBus eject */
576 			if (temp == ~(u32)0)
577 				return -ESHUTDOWN;
578 			if (!(temp & RH_PS_PRS))
579 				break;
580 			udelay (500);
581 		}
582 
583 		if (!(temp & RH_PS_CCS))
584 			break;
585 		if (temp & RH_PS_PRSC)
586 			ohci_writel (ohci, RH_PS_PRSC, portstat);
587 
588 		/* start the next reset, sleep till it's probably done */
589 		ohci_writel (ohci, RH_PS_PRS, portstat);
590 		msleep(PORT_RESET_HW_MSEC);
591 		now = ohci_readl(ohci, &ohci->regs->fmnumber);
592 	} while (tick_before(now, reset_done));
593 	/* caller synchronizes using PRSC */
594 
595 	return 0;
596 }
597 
598 static int ohci_hub_control (
599 	struct usb_hcd	*hcd,
600 	u16		typeReq,
601 	u16		wValue,
602 	u16		wIndex,
603 	char		*buf,
604 	u16		wLength
605 ) {
606 	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
607 	int		ports = hcd_to_bus (hcd)->root_hub->maxchild;
608 	u32		temp;
609 	int		retval = 0;
610 
611 	if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
612 		return -ESHUTDOWN;
613 
614 	switch (typeReq) {
615 	case ClearHubFeature:
616 		switch (wValue) {
617 		case C_HUB_OVER_CURRENT:
618 			ohci_writel (ohci, RH_HS_OCIC,
619 					&ohci->regs->roothub.status);
620 		case C_HUB_LOCAL_POWER:
621 			break;
622 		default:
623 			goto error;
624 		}
625 		break;
626 	case ClearPortFeature:
627 		if (!wIndex || wIndex > ports)
628 			goto error;
629 		wIndex--;
630 
631 		switch (wValue) {
632 		case USB_PORT_FEAT_ENABLE:
633 			temp = RH_PS_CCS;
634 			break;
635 		case USB_PORT_FEAT_C_ENABLE:
636 			temp = RH_PS_PESC;
637 			break;
638 		case USB_PORT_FEAT_SUSPEND:
639 			temp = RH_PS_POCI;
640 			break;
641 		case USB_PORT_FEAT_C_SUSPEND:
642 			temp = RH_PS_PSSC;
643 			break;
644 		case USB_PORT_FEAT_POWER:
645 			temp = RH_PS_LSDA;
646 			break;
647 		case USB_PORT_FEAT_C_CONNECTION:
648 			temp = RH_PS_CSC;
649 			break;
650 		case USB_PORT_FEAT_C_OVER_CURRENT:
651 			temp = RH_PS_OCIC;
652 			break;
653 		case USB_PORT_FEAT_C_RESET:
654 			temp = RH_PS_PRSC;
655 			break;
656 		default:
657 			goto error;
658 		}
659 		ohci_writel (ohci, temp,
660 				&ohci->regs->roothub.portstatus [wIndex]);
661 		// ohci_readl (ohci, &ohci->regs->roothub.portstatus [wIndex]);
662 		break;
663 	case GetHubDescriptor:
664 		ohci_hub_descriptor (ohci, (struct usb_hub_descriptor *) buf);
665 		break;
666 	case GetHubStatus:
667 		temp = roothub_status (ohci) & ~(RH_HS_CRWE | RH_HS_DRWE);
668 		put_unaligned(cpu_to_le32 (temp), (__le32 *) buf);
669 		break;
670 	case GetPortStatus:
671 		if (!wIndex || wIndex > ports)
672 			goto error;
673 		wIndex--;
674 		temp = roothub_portstatus (ohci, wIndex);
675 		put_unaligned(cpu_to_le32 (temp), (__le32 *) buf);
676 
677 #ifndef	OHCI_VERBOSE_DEBUG
678 	if (*(u16*)(buf+2))	/* only if wPortChange is interesting */
679 #endif
680 		dbg_port (ohci, "GetStatus", wIndex, temp);
681 		break;
682 	case SetHubFeature:
683 		switch (wValue) {
684 		case C_HUB_OVER_CURRENT:
685 			// FIXME:  this can be cleared, yes?
686 		case C_HUB_LOCAL_POWER:
687 			break;
688 		default:
689 			goto error;
690 		}
691 		break;
692 	case SetPortFeature:
693 		if (!wIndex || wIndex > ports)
694 			goto error;
695 		wIndex--;
696 		switch (wValue) {
697 		case USB_PORT_FEAT_SUSPEND:
698 #ifdef	CONFIG_USB_OTG
699 			if (hcd->self.otg_port == (wIndex + 1)
700 					&& hcd->self.b_hnp_enable)
701 				start_hnp(ohci);
702 			else
703 #endif
704 			ohci_writel (ohci, RH_PS_PSS,
705 				&ohci->regs->roothub.portstatus [wIndex]);
706 			break;
707 		case USB_PORT_FEAT_POWER:
708 			ohci_writel (ohci, RH_PS_PPS,
709 				&ohci->regs->roothub.portstatus [wIndex]);
710 			break;
711 		case USB_PORT_FEAT_RESET:
712 			retval = root_port_reset (ohci, wIndex);
713 			break;
714 		default:
715 			goto error;
716 		}
717 		break;
718 
719 	default:
720 error:
721 		/* "protocol stall" on error */
722 		retval = -EPIPE;
723 	}
724 	return retval;
725 }
726 
727