aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/usb/host/ohci-hub.c
blob: db09dae7b557a18063d424a3ffc58c1edb8ccca8 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
/*
 * OHCI HCD (Host Controller Driver) for USB.
 *
 * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
 * (C) Copyright 2000-2004 David Brownell <dbrownell@users.sourceforge.net>
 *
 * This file is licenced under GPL
 */

/*-------------------------------------------------------------------------*/

/*
 * OHCI Root Hub ... the nonsharable stuff
 */

#define dbg_port(hc,label,num,value) \
	ohci_dbg (hc, \
		"%s roothub.portstatus [%d] " \
		"= 0x%08x%s%s%s%s%s%s%s%s%s%s%s%s\n", \
		label, num, temp, \
		(temp & RH_PS_PRSC) ? " PRSC" : "", \
		(temp & RH_PS_OCIC) ? " OCIC" : "", \
		(temp & RH_PS_PSSC) ? " PSSC" : "", \
		(temp & RH_PS_PESC) ? " PESC" : "", \
		(temp & RH_PS_CSC) ? " CSC" : "", \
		\
		(temp & RH_PS_LSDA) ? " LSDA" : "", \
		(temp & RH_PS_PPS) ? " PPS" : "", \
		(temp & RH_PS_PRS) ? " PRS" : "", \
		(temp & RH_PS_POCI) ? " POCI" : "", \
		(temp & RH_PS_PSS) ? " PSS" : "", \
		\
		(temp & RH_PS_PES) ? " PES" : "", \
		(temp & RH_PS_CCS) ? " CCS" : "" \
		);

/*-------------------------------------------------------------------------*/

#define OHCI_SCHED_ENABLES \
	(OHCI_CTRL_CLE|OHCI_CTRL_BLE|OHCI_CTRL_PLE|OHCI_CTRL_IE)

static void dl_done_list (struct ohci_hcd *);
static void finish_unlinks (struct ohci_hcd *, u16);

#ifdef	CONFIG_PM
static int ohci_rh_suspend (struct ohci_hcd *ohci, int autostop)
__releases(ohci->lock)
__acquires(ohci->lock)
{
	int			status = 0;

	ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
	switch (ohci->hc_control & OHCI_CTRL_HCFS) {
	case OHCI_USB_RESUME:
		ohci_dbg (ohci, "resume/suspend?\n");
		ohci->hc_control &= ~OHCI_CTRL_HCFS;
		ohci->hc_control |= OHCI_USB_RESET;
		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
		(void) ohci_readl (ohci, &ohci->regs->control);
		/* FALL THROUGH */
	case OHCI_USB_RESET:
		status = -EBUSY;
		ohci_dbg (ohci, "needs reinit!\n");
		goto done;
	case OHCI_USB_SUSPEND:
		if (!ohci->autostop) {
			ohci_dbg (ohci, "already suspended\n");
			goto done;
		}
	}
	ohci_dbg (ohci, "%s root hub\n",
			autostop ? "auto-stop" : "suspend");

	/* First stop any processing */
	if (!autostop && (ohci->hc_control & OHCI_SCHED_ENABLES)) {
		ohci->hc_control &= ~OHCI_SCHED_ENABLES;
		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
		ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
		ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrstatus);

		/* sched disables take effect on the next frame,
		 * then the last WDH could take 6+ msec
		 */
		ohci_dbg (ohci, "stopping schedules ...\n");
		ohci->autostop = 0;
		spin_unlock_irq (&ohci->lock);
		msleep (8);
		spin_lock_irq (&ohci->lock);
	}
	dl_done_list (ohci);
	finish_unlinks (ohci, ohci_frame_no(ohci));

	/* maybe resume can wake root hub */
	if (ohci_to_hcd(ohci)->self.root_hub->do_remote_wakeup || autostop) {
		ohci->hc_control |= OHCI_CTRL_RWE;
	} else {
		ohci_writel(ohci, OHCI_INTR_RHSC | OHCI_INTR_RD,
				&ohci->regs->intrdisable);
		ohci->hc_control &= ~OHCI_CTRL_RWE;
	}

	/* Suspend hub ... this is the "global (to this bus) suspend" mode,
	 * which doesn't imply ports will first be individually suspended.
	 */
	ohci->hc_control &= ~OHCI_CTRL_HCFS;
	ohci->hc_control |= OHCI_USB_SUSPEND;
	ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
	(void) ohci_readl (ohci, &ohci->regs->control);

	/* no resumes until devices finish suspending */
	if (!autostop) {
		ohci->next_statechange = jiffies + msecs_to_jiffies (5);
		ohci->autostop = 0;
		ohci->rh_state = OHCI_RH_SUSPENDED;
	}

done:
	return status;
}

static inline struct ed *find_head (struct ed *ed)
{
	/* for bulk and control lists */
	while (ed->ed_prev)
		ed = ed->ed_prev;
	return ed;
}

/* caller has locked the root hub */
static int ohci_rh_resume (struct ohci_hcd *ohci)
__releases(ohci->lock)
__acquires(ohci->lock)
{
	struct usb_hcd		*hcd = ohci_to_hcd (ohci);
	u32			temp, enables;
	int			status = -EINPROGRESS;
	int			autostopped = ohci->autostop;

	ohci->autostop = 0;
	ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);

	if (ohci->hc_control & (OHCI_CTRL_IR | OHCI_SCHED_ENABLES)) {
		/* this can happen after resuming a swsusp snapshot */
		if (ohci->rh_state != OHCI_RH_RUNNING) {
			ohci_dbg (ohci, "BIOS/SMM active, control %03x\n",
					ohci->hc_control);
			status = -EBUSY;
		/* this happens when pmcore resumes HC then root */
		} else {
			ohci_dbg (ohci, "duplicate resume\n");
			status = 0;
		}
	} else switch (ohci->hc_control & OHCI_CTRL_HCFS) {
	case OHCI_USB_SUSPEND:
		ohci->hc_control &= ~(OHCI_CTRL_HCFS|OHCI_SCHED_ENABLES);
		ohci->hc_control |= OHCI_USB_RESUME;
		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
		(void) ohci_readl (ohci, &ohci->regs->control);
		ohci_dbg (ohci, "%s root hub\n",
				autostopped ? "auto-start" : "resume");
		break;
	case OHCI_USB_RESUME:
		/* HCFS changes sometime after INTR_RD */
		ohci_dbg(ohci, "%swakeup root hub\n",
				autostopped ? "auto-" : "");
		break;
	case OHCI_USB_OPER:
		/* this can happen after resuming a swsusp snapshot */
		ohci_dbg (ohci, "snapshot resume? reinit\n");
		status = -EBUSY;
		break;
	default:		/* RESET, we lost power */
		ohci_dbg (ohci, "lost power\n");
		status = -EBUSY;
	}
	if (status == -EBUSY) {
		if (!autostopped) {
			spin_unlock_irq (&ohci->lock);
			(void) ohci_init (ohci);
			status = ohci_restart (ohci);

			usb_root_hub_lost_power(hcd->self.root_hub);

			spin_lock_irq (&ohci->lock);
		}
		return status;
	}
	if (status != -EINPROGRESS)
		return status;
	if (autostopped)
		goto skip_resume;
	spin_unlock_irq (&ohci->lock);

	/* Some controllers (lucent erratum) need extra-long delays */
	msleep (20 /* usb 11.5.1.10 */ + 12 /* 32 msec counter */ + 1);

	temp = ohci_readl (ohci, &ohci->regs->control);
	temp &= OHCI_CTRL_HCFS;
	if (temp != OHCI_USB_RESUME) {
		ohci_err (ohci, "controller won't resume\n");
		spin_lock_irq(&ohci->lock);
		return -EBUSY;
	}

	/* disable old schedule state, reinit from scratch */
	ohci_writel (ohci, 0, &ohci->regs->ed_controlhead);
	ohci_writel (ohci, 0, &ohci->regs->ed_controlcurrent);
	ohci_writel (ohci, 0, &ohci->regs->ed_bulkhead);
	ohci_writel (ohci, 0, &ohci->regs->ed_bulkcurrent);
	ohci_writel (ohci, 0, &ohci->regs->ed_periodcurrent);
	ohci_writel (ohci, (u32) ohci->hcca_dma, &ohci->regs->hcca);

	/* Sometimes PCI D3 suspend trashes frame timings ... */
	periodic_reinit (ohci);

	/* the following code is executed with ohci->lock held and
	 * irqs disabled if and only if autostopped is true
	 */

skip_resume:
	/* interrupts might have been disabled */
	ohci_writel (ohci, OHCI_INTR_INIT, &ohci->regs->intrenable);
	if (ohci->ed_rm_list)
		ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrenable);

	/* Then re-enable operations */
	ohci_writel (ohci, OHCI_USB_OPER, &ohci->regs->control);
	(void) ohci_readl (ohci, &ohci->regs->control);
	if (!autostopped)
		msleep (3);

	temp = ohci->hc_control;
	temp &= OHCI_CTRL_RWC;
	temp |= OHCI_CONTROL_INIT | OHCI_USB_OPER;
	ohci->hc_control = temp;
	ohci_writel (ohci, temp, &ohci->regs->control);
	(void) ohci_readl (ohci, &ohci->regs->control);

	/* TRSMRCY */
	if (!autostopped) {
		msleep (10);
		spin_lock_irq (&ohci->lock);
	}
	/* now ohci->lock is always held and irqs are always disabled */

	/* keep it alive for more than ~5x suspend + resume costs */
	ohci->next_statechange = jiffies + STATECHANGE_DELAY;

	/* maybe turn schedules back on */
	enables = 0;
	temp = 0;
	if (!ohci->ed_rm_list) {
		if (ohci->ed_controltail) {
			ohci_writel (ohci,
					find_head (ohci->ed_controltail)->dma,
					&ohci->regs->ed_controlhead);
			enables |= OHCI_CTRL_CLE;
			temp |= OHCI_CLF;
		}
		if (ohci->ed_bulktail) {
			ohci_writel (ohci, find_head (ohci->ed_bulktail)->dma,
				&ohci->regs->ed_bulkhead);
			enables |= OHCI_CTRL_BLE;
			temp |= OHCI_BLF;
		}
	}
	if (hcd->self.bandwidth_isoc_reqs || hcd->self.bandwidth_int_reqs)
		enables |= OHCI_CTRL_PLE|OHCI_CTRL_IE;
	if (enables) {
		ohci_dbg (ohci, "restarting schedules ... %08x\n", enables);
		ohci->hc_control |= enables;
		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
		if (temp)
			ohci_writel (ohci, temp, &ohci->regs->cmdstatus);
		(void) ohci_readl (ohci, &ohci->regs->control);
	}

	ohci->rh_state = OHCI_RH_RUNNING;
	return 0;
}

static int ohci_bus_suspend (struct usb_hcd *hcd)
{
	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
	int			rc;

	spin_lock_irq (&ohci->lock);

	if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
		rc = -ESHUTDOWN;
	else
		rc = ohci_rh_suspend (ohci, 0);
	spin_unlock_irq (&ohci->lock);
	return rc;
}

static int ohci_bus_resume (struct usb_hcd *hcd)
{
	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
	int			rc;

	if (time_before (jiffies, ohci->next_statechange))
		msleep(5);

	spin_lock_irq (&ohci->lock);

	if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
		rc = -ESHUTDOWN;
	else
		rc = ohci_rh_resume (ohci);
	spin_unlock_irq (&ohci->lock);

	/* poll until we know a device is connected or we autostop */
	if (rc == 0)
		usb_hcd_poll_rh_status(hcd);
	return rc;
}

/* Carry out polling-, autostop-, and autoresume-related state changes */
static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
		int any_connected, int rhsc_status)
{
	int	poll_rh = 1;
	int	rhsc_enable;

	/* Some broken controllers never turn off RHSC in the interrupt
	 * status register.  For their sake we won't re-enable RHSC
	 * interrupts if the interrupt bit is already active.
	 */
	rhsc_enable = ohci_readl(ohci, &ohci->regs->intrenable) &
			OHCI_INTR_RHSC;

	switch (ohci->hc_control & OHCI_CTRL_HCFS) {
	case OHCI_USB_OPER:
		/* If no status changes are pending, enable RHSC interrupts. */
		if (!rhsc_enable && !rhsc_status && !changed) {
			rhsc_enable = OHCI_INTR_RHSC;
			ohci_writel(ohci, rhsc_enable, &ohci->regs->intrenable);
		}

		/* Keep on polling until we know a device is connected
		 * and RHSC is enabled, or until we autostop.
		 */
		if (!ohci->autostop) {
			if (any_connected ||
					!device_may_wakeup(&ohci_to_hcd(ohci)
						->self.root_hub->dev)) {
				if (rhsc_enable)
					poll_rh = 0;
			} else {
				ohci->autostop = 1;
				ohci->next_statechange = jiffies + HZ;
			}

		/* if no devices have been attached for one second, autostop */
		} else {
			if (changed || any_connected) {
				ohci->autostop = 0;
				ohci->next_statechange = jiffies +
						STATECHANGE_DELAY;
			} else if (time_after_eq(jiffies,
						ohci->next_statechange)
					&& !ohci->ed_rm_list
					&& !(ohci->hc_control &
						OHCI_SCHED_ENABLES)) {
				ohci_rh_suspend(ohci, 1);
				if (rhsc_enable)
					poll_rh = 0;
			}
		}
		break;

	case OHCI_USB_SUSPEND:
	case OHCI_USB_RESUME:
		/* if there is a port change, autostart or ask to be resumed */
		if (changed) {
			if (ohci->autostop)
				ohci_rh_resume(ohci);
			else
				usb_hcd_resume_root_hub(ohci_to_hcd(ohci));

		/* If remote wakeup is disabled, stop polling */
		} else if (!ohci->autostop &&
				!ohci_to_hcd(ohci)->self.root_hub->
					do_remote_wakeup) {
			poll_rh = 0;

		} else {
			/* If no status changes are pending,
			 * enable RHSC interrupts
			 */
			if (!rhsc_enable && !rhsc_status) {
				rhsc_enable = OHCI_INTR_RHSC;
				ohci_writel(ohci, rhsc_enable,
						&ohci->regs->intrenable);
			}
			/* Keep polling until RHSC is enabled */
			if (rhsc_enable)
				poll_rh = 0;
		}
		break;
	}
	return poll_rh;
}

#else	/* CONFIG_PM */

static inline int ohci_rh_resume(struct ohci_hcd *ohci)
{
	return 0;
}

/* Carry out polling-related state changes.
 * autostop isn't used when CONFIG_PM is turned off.
 */
static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
		int any_connected, int rhsc_status)
{
	/* If RHSC is enabled, don't poll */
	if (ohci_readl(ohci, &ohci->regs->intrenable) & OHCI_INTR_RHSC)
		return 0;

	/* If status changes are pending, continue polling.
	 * Conversely, if no status changes are pending but the RHSC
	 * status bit was set, then RHSC may be broken so continue polling.
	 */
	if (changed || rhsc_status)
		return 1;

	/* It's safe to re-enable RHSC interrupts */
	ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrenable);
	return 0;
}

#endif	/* CONFIG_PM */

/*-------------------------------------------------------------------------*/

/* build "status change" packet (one or two bytes) from HC registers */

static int
ohci_hub_status_data (struct usb_hcd *hcd, char *buf)
{
	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
	int		i, changed = 0, length = 1;
	int		any_connected = 0;
	int		rhsc_status;
	unsigned long	flags;

	spin_lock_irqsave (&ohci->lock, flags);
	if (!HCD_HW_ACCESSIBLE(hcd))
		goto done;

	/* undocumented erratum seen on at least rev D */
	if ((ohci->flags & OHCI_QUIRK_AMD756)
			&& (roothub_a (ohci) & RH_A_NDP) > MAX_ROOT_PORTS) {
		ohci_warn (ohci, "bogus NDP, rereads as NDP=%d\n",
			  ohci_readl (ohci, &ohci->regs->roothub.a) & RH_A_NDP);
		/* retry later; "should not happen" */
		goto done;
	}

	/* init status */
	if (roothub_status (ohci) & (RH_HS_LPSC | RH_HS_OCIC))
		buf [0] = changed = 1;
	else
		buf [0] = 0;
	if (ohci->num_ports > 7) {
		buf [1] = 0;
		length++;
	}

	/* Clear the RHSC status flag before reading the port statuses */
	ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrstatus);
	rhsc_status = ohci_readl(ohci, &ohci->regs->intrstatus) &
			OHCI_INTR_RHSC;

	/* look at each port */
	for (i = 0; i < ohci->num_ports; i++) {
		u32	status = roothub_portstatus (ohci, i);

		/* can't autostop if ports are connected */
		any_connected |= (status & RH_PS_CCS);

		if (status & (RH_PS_CSC | RH_PS_PESC | RH_PS_PSSC
				| RH_PS_OCIC | RH_PS_PRSC)) {
			changed = 1;
			if (i < 7)
			    buf [0] |= 1 << (i + 1);
			else
			    buf [1] |= 1 << (i - 7);
		}
	}

	if (ohci_root_hub_state_changes(ohci, changed,
			any_connected, rhsc_status))
		set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
	else
		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);


done:
	spin_unlock_irqrestore (&ohci->lock, flags);

	return changed ? length : 0;
}

/*-------------------------------------------------------------------------*/

static void
ohci_hub_descriptor (
	struct ohci_hcd			*ohci,
	struct usb_hub_descriptor	*desc
) {
	u32		rh = roothub_a (ohci);
	u16		temp;

	desc->bDescriptorType = 0x29;
	desc->bPwrOn2PwrGood = (rh & RH_A_POTPGT) >> 24;
	desc->bHubContrCurrent = 0;

	desc->bNbrPorts = ohci->num_ports;
	temp = 1 + (ohci->num_ports / 8);
	desc->bDescLength = 7 + 2 * temp;

	temp = 0;
	if (rh & RH_A_NPS)		/* no power switching? */
	    temp |= 0x0002;
	if (rh & RH_A_PSM)		/* per-port power switching? */
	    temp |= 0x0001;
	if (rh & RH_A_NOCP)		/* no overcurrent reporting? */
	    temp |= 0x0010;
	else if (rh & RH_A_OCPM)	/* per-port overcurrent reporting? */
	    temp |= 0x0008;
	desc->wHubCharacteristics = (__force __u16)cpu_to_hc16(ohci, temp);

	/* ports removable, and usb 1.0 legacy PortPwrCtrlMask */
	rh = roothub_b (ohci);
	memset(desc->u.hs.DeviceRemovable, 0xff,
			sizeof(desc->u.hs.DeviceRemovable));
	desc->u.hs.DeviceRemovable[0] = rh & RH_B_DR;
	if (ohci->num_ports > 7) {
		desc->u.hs.DeviceRemovable[1] = (rh & RH_B_DR) >> 8;
		desc->u.hs.DeviceRemovable[2] = 0xff;
	} else
		desc->u.hs.DeviceRemovable[1] = 0xff;
}

/*-------------------------------------------------------------------------*/

#ifdef	CONFIG_USB_OTG

static int ohci_start_port_reset (struct usb_hcd *hcd, unsigned port)
{
	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
	u32			status;

	if (!port)
		return -EINVAL;
	port--;

	/* start port reset before HNP protocol times out */
	status = ohci_readl(ohci, &ohci->regs->roothub.portstatus [port]);
	if (!(status & RH_PS_CCS))
		return -ENODEV;

	/* khubd will finish the reset later */
	ohci_writel(ohci, RH_PS_PRS, &ohci->regs->roothub.portstatus [port]);
	return 0;
}

#else

#define	ohci_start_port_reset		NULL

#endif

/*-------------------------------------------------------------------------*/


/* See usb 7.1.7.5:  root hubs must issue at least 50 msec reset signaling,
 * not necessarily continuous ... to guard against resume signaling.
 * The short timeout is safe for non-root hubs, and is backward-compatible
 * with earlier Linux hosts.
 */
#ifdef	CONFIG_USB_SUSPEND
#define	PORT_RESET_MSEC		50
#else
#define	PORT_RESET_MSEC		10
#endif

/* this timer value might be vendor-specific ... */
#define	PORT_RESET_HW_MSEC	10

/* wrap-aware logic morphed from <linux/jiffies.h> */
#define tick_before(t1,t2) ((s16)(((s16)(t1))-((s16)(t2))) < 0)

/* called from some task, normally khubd */
static inline int root_port_reset (struct ohci_hcd *ohci, unsigned port)
{
	__hc32 __iomem *portstat = &ohci->regs->roothub.portstatus [port];
	u32	temp = 0;
	u16	now = ohci_readl(ohci, &ohci->regs->fmnumber);
	u16	reset_done = now + PORT_RESET_MSEC;
	int	limit_1 = DIV_ROUND_UP(PORT_RESET_MSEC, PORT_RESET_HW_MSEC);

	/* build a "continuous enough" reset signal, with up to
	 * 3msec gap between pulses.  scheduler HZ==100 must work;
	 * this might need to be deadline-scheduled.
	 */
	do {
		int limit_2;

		/* spin until any current reset finishes */
		limit_2 = PORT_RESET_HW_MSEC * 2;
		while (--limit_2 >= 0) {
			temp = ohci_readl (ohci, portstat);
			/* handle e.g. CardBus eject */
			if (temp == ~(u32)0)
				return -ESHUTDOWN;
			if (!(temp & RH_PS_PRS))
				break;
			udelay (500);
		}

		/* timeout (a hardware error) has been observed when
		 * EHCI sets CF while this driver is resetting a port;
		 * presumably other disconnect paths might do it too.
		 */
		if (limit_2 < 0) {
			ohci_dbg(ohci,
				"port[%d] reset timeout, stat %08x\n",
				port, temp);
			break;
		}

		if (!(temp & RH_PS_CCS))
			break;
		if (temp & RH_PS_PRSC)
			ohci_writel (ohci, RH_PS_PRSC, portstat);

		/* start the next reset, sleep till it's probably done */
		ohci_writel (ohci, RH_PS_PRS, portstat);
		msleep(PORT_RESET_HW_MSEC);
		now = ohci_readl(ohci, &ohci->regs->fmnumber);
	} while (tick_before(now, reset_done) && --limit_1 >= 0);

	/* caller synchronizes using PRSC ... and handles PRS
	 * still being set when this returns.
	 */

	return 0;
}

static int ohci_hub_control (
	struct usb_hcd	*hcd,
	u16		typeReq,
	u16		wValue,
	u16		wIndex,
	char		*buf,
	u16		wLength
) {
	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
	int		ports = ohci->num_ports;
	u32		temp;
	int		retval = 0;

	if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
		return -ESHUTDOWN;

	switch (typeReq) {
	case ClearHubFeature:
		switch (wValue) {
		case C_HUB_OVER_CURRENT:
			ohci_writel (ohci, RH_HS_OCIC,
					&ohci->regs->roothub.status);
		case C_HUB_LOCAL_POWER:
			break;
		default:
			goto error;
		}
		break;
	case ClearPortFeature:
		if (!wIndex || wIndex > ports)
			goto error;
		wIndex--;

		switch (wValue) {
		case USB_PORT_FEAT_ENABLE:
			temp = RH_PS_CCS;
			break;
		case USB_PORT_FEAT_C_ENABLE:
			temp = RH_PS_PESC;
			break;
		case USB_PORT_FEAT_SUSPEND:
			temp = RH_PS_POCI;
			break;
		case USB_PORT_FEAT_C_SUSPEND:
			temp = RH_PS_PSSC;
			break;
		case USB_PORT_FEAT_POWER:
			temp = RH_PS_LSDA;
			break;
		case USB_PORT_FEAT_C_CONNECTION:
			temp = RH_PS_CSC;
			break;
		case USB_PORT_FEAT_C_OVER_CURRENT:
			temp = RH_PS_OCIC;
			break;
		case USB_PORT_FEAT_C_RESET:
			temp = RH_PS_PRSC;
			break;
		default:
			goto error;
		}
		ohci_writel (ohci, temp,
				&ohci->regs->roothub.portstatus [wIndex]);
		// ohci_readl (ohci, &ohci->regs->roothub.portstatus [wIndex]);
		break;
	case GetHubDescriptor:
		ohci_hub_descriptor (ohci, (struct usb_hub_descriptor *) buf);
		break;
	case GetHubStatus:
		temp = roothub_status (ohci) & ~(RH_HS_CRWE | RH_HS_DRWE);
		put_unaligned_le32(temp, buf);
		break;
	case GetPortStatus:
		if (!wIndex || wIndex > ports)
			goto error;
		wIndex--;
		temp = roothub_portstatus (ohci, wIndex);
		put_unaligned_le32(temp, buf);

#ifndef	OHCI_VERBOSE_DEBUG
	if (*(u16*)(buf+2))	/* only if wPortChange is interesting */
#endif
		dbg_port (ohci, "GetStatus", wIndex, temp);
		break;
	case SetHubFeature:
		switch (wValue) {
		case C_HUB_OVER_CURRENT:
			// FIXME:  this can be cleared, yes?
		case C_HUB_LOCAL_POWER:
			break;
		default:
			goto error;
		}
		break;
	case SetPortFeature:
		if (!wIndex || wIndex > ports)
			goto error;
		wIndex--;
		switch (wValue) {
		case USB_PORT_FEAT_SUSPEND:
#ifdef	CONFIG_USB_OTG
			if (hcd->self.otg_port == (wIndex + 1)
					&& hcd->self.b_hnp_enable)
				ohci->start_hnp(ohci);
			else
#endif
			ohci_writel (ohci, RH_PS_PSS,
				&ohci->regs->roothub.portstatus [wIndex]);
			break;
		case USB_PORT_FEAT_POWER:
			ohci_writel (ohci, RH_PS_PPS,
				&ohci->regs->roothub.portstatus [wIndex]);
			break;
		case USB_PORT_FEAT_RESET:
			retval = root_port_reset (ohci, wIndex);
			break;
		default:
			goto error;
		}
		break;

	default:
error:
		/* "protocol stall" on error */
		retval = -EPIPE;
	}
	return retval;
}