xref: /openbmc/linux/drivers/usb/host/ohci-hub.c (revision 84d517f3)
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 	/*
234 	 * The following code is executed with ohci->lock held and
235 	 * irqs disabled if and only if autostopped is true.  This
236 	 * will cause sparse to warn about a "context imbalance".
237 	 */
238 skip_resume:
239 	/* interrupts might have been disabled */
240 	ohci_writel (ohci, OHCI_INTR_INIT, &ohci->regs->intrenable);
241 	if (ohci->ed_rm_list)
242 		ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrenable);
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 	if (!autostopped)
248 		msleep (3);
249 
250 	temp = ohci->hc_control;
251 	temp &= OHCI_CTRL_RWC;
252 	temp |= OHCI_CONTROL_INIT | OHCI_USB_OPER;
253 	ohci->hc_control = temp;
254 	ohci_writel (ohci, temp, &ohci->regs->control);
255 	(void) ohci_readl (ohci, &ohci->regs->control);
256 
257 	/* TRSMRCY */
258 	if (!autostopped) {
259 		msleep (10);
260 		spin_lock_irq (&ohci->lock);
261 	}
262 	/* now ohci->lock is always held and irqs are always disabled */
263 
264 	/* keep it alive for more than ~5x suspend + resume costs */
265 	ohci->next_statechange = jiffies + STATECHANGE_DELAY;
266 
267 	/* maybe turn schedules back on */
268 	enables = 0;
269 	temp = 0;
270 	if (!ohci->ed_rm_list) {
271 		if (ohci->ed_controltail) {
272 			ohci_writel (ohci,
273 					find_head (ohci->ed_controltail)->dma,
274 					&ohci->regs->ed_controlhead);
275 			enables |= OHCI_CTRL_CLE;
276 			temp |= OHCI_CLF;
277 		}
278 		if (ohci->ed_bulktail) {
279 			ohci_writel (ohci, find_head (ohci->ed_bulktail)->dma,
280 				&ohci->regs->ed_bulkhead);
281 			enables |= OHCI_CTRL_BLE;
282 			temp |= OHCI_BLF;
283 		}
284 	}
285 	if (hcd->self.bandwidth_isoc_reqs || hcd->self.bandwidth_int_reqs)
286 		enables |= OHCI_CTRL_PLE|OHCI_CTRL_IE;
287 	if (enables) {
288 		ohci_dbg (ohci, "restarting schedules ... %08x\n", enables);
289 		ohci->hc_control |= enables;
290 		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
291 		if (temp)
292 			ohci_writel (ohci, temp, &ohci->regs->cmdstatus);
293 		(void) ohci_readl (ohci, &ohci->regs->control);
294 	}
295 
296 	ohci->rh_state = OHCI_RH_RUNNING;
297 	return 0;
298 }
299 
300 static int ohci_bus_suspend (struct usb_hcd *hcd)
301 {
302 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
303 	int			rc;
304 
305 	spin_lock_irq (&ohci->lock);
306 
307 	if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
308 		rc = -ESHUTDOWN;
309 	else
310 		rc = ohci_rh_suspend (ohci, 0);
311 	spin_unlock_irq (&ohci->lock);
312 	return rc;
313 }
314 
315 static int ohci_bus_resume (struct usb_hcd *hcd)
316 {
317 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
318 	int			rc;
319 
320 	if (time_before (jiffies, ohci->next_statechange))
321 		msleep(5);
322 
323 	spin_lock_irq (&ohci->lock);
324 
325 	if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
326 		rc = -ESHUTDOWN;
327 	else
328 		rc = ohci_rh_resume (ohci);
329 	spin_unlock_irq (&ohci->lock);
330 
331 	/* poll until we know a device is connected or we autostop */
332 	if (rc == 0)
333 		usb_hcd_poll_rh_status(hcd);
334 	return rc;
335 }
336 
337 /* Carry out polling-, autostop-, and autoresume-related state changes */
338 static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
339 		int any_connected, int rhsc_status)
340 {
341 	int	poll_rh = 1;
342 	int	rhsc_enable;
343 
344 	/* Some broken controllers never turn off RHSC in the interrupt
345 	 * status register.  For their sake we won't re-enable RHSC
346 	 * interrupts if the interrupt bit is already active.
347 	 */
348 	rhsc_enable = ohci_readl(ohci, &ohci->regs->intrenable) &
349 			OHCI_INTR_RHSC;
350 
351 	switch (ohci->hc_control & OHCI_CTRL_HCFS) {
352 	case OHCI_USB_OPER:
353 		/* If no status changes are pending, enable RHSC interrupts. */
354 		if (!rhsc_enable && !rhsc_status && !changed) {
355 			rhsc_enable = OHCI_INTR_RHSC;
356 			ohci_writel(ohci, rhsc_enable, &ohci->regs->intrenable);
357 		}
358 
359 		/* Keep on polling until we know a device is connected
360 		 * and RHSC is enabled, or until we autostop.
361 		 */
362 		if (!ohci->autostop) {
363 			if (any_connected ||
364 					!device_may_wakeup(&ohci_to_hcd(ohci)
365 						->self.root_hub->dev)) {
366 				if (rhsc_enable)
367 					poll_rh = 0;
368 			} else {
369 				ohci->autostop = 1;
370 				ohci->next_statechange = jiffies + HZ;
371 			}
372 
373 		/* if no devices have been attached for one second, autostop */
374 		} else {
375 			if (changed || any_connected) {
376 				ohci->autostop = 0;
377 				ohci->next_statechange = jiffies +
378 						STATECHANGE_DELAY;
379 			} else if (time_after_eq(jiffies,
380 						ohci->next_statechange)
381 					&& !ohci->ed_rm_list
382 					&& !(ohci->hc_control &
383 						OHCI_SCHED_ENABLES)) {
384 				ohci_rh_suspend(ohci, 1);
385 				if (rhsc_enable)
386 					poll_rh = 0;
387 			}
388 		}
389 		break;
390 
391 	case OHCI_USB_SUSPEND:
392 	case OHCI_USB_RESUME:
393 		/* if there is a port change, autostart or ask to be resumed */
394 		if (changed) {
395 			if (ohci->autostop)
396 				ohci_rh_resume(ohci);
397 			else
398 				usb_hcd_resume_root_hub(ohci_to_hcd(ohci));
399 
400 		/* If remote wakeup is disabled, stop polling */
401 		} else if (!ohci->autostop &&
402 				!ohci_to_hcd(ohci)->self.root_hub->
403 					do_remote_wakeup) {
404 			poll_rh = 0;
405 
406 		} else {
407 			/* If no status changes are pending,
408 			 * enable RHSC interrupts
409 			 */
410 			if (!rhsc_enable && !rhsc_status) {
411 				rhsc_enable = OHCI_INTR_RHSC;
412 				ohci_writel(ohci, rhsc_enable,
413 						&ohci->regs->intrenable);
414 			}
415 			/* Keep polling until RHSC is enabled */
416 			if (rhsc_enable)
417 				poll_rh = 0;
418 		}
419 		break;
420 	}
421 	return poll_rh;
422 }
423 
424 #else	/* CONFIG_PM */
425 
426 static inline int ohci_rh_resume(struct ohci_hcd *ohci)
427 {
428 	return 0;
429 }
430 
431 /* Carry out polling-related state changes.
432  * autostop isn't used when CONFIG_PM is turned off.
433  */
434 static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
435 		int any_connected, int rhsc_status)
436 {
437 	/* If RHSC is enabled, don't poll */
438 	if (ohci_readl(ohci, &ohci->regs->intrenable) & OHCI_INTR_RHSC)
439 		return 0;
440 
441 	/* If status changes are pending, continue polling.
442 	 * Conversely, if no status changes are pending but the RHSC
443 	 * status bit was set, then RHSC may be broken so continue polling.
444 	 */
445 	if (changed || rhsc_status)
446 		return 1;
447 
448 	/* It's safe to re-enable RHSC interrupts */
449 	ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrenable);
450 	return 0;
451 }
452 
453 #endif	/* CONFIG_PM */
454 
455 /*-------------------------------------------------------------------------*/
456 
457 /* build "status change" packet (one or two bytes) from HC registers */
458 
459 int 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 EXPORT_SYMBOL_GPL(ohci_hub_status_data);
525 
526 /*-------------------------------------------------------------------------*/
527 
528 static void
529 ohci_hub_descriptor (
530 	struct ohci_hcd			*ohci,
531 	struct usb_hub_descriptor	*desc
532 ) {
533 	u32		rh = roothub_a (ohci);
534 	u16		temp;
535 
536 	desc->bDescriptorType = 0x29;
537 	desc->bPwrOn2PwrGood = (rh & RH_A_POTPGT) >> 24;
538 	desc->bHubContrCurrent = 0;
539 
540 	desc->bNbrPorts = ohci->num_ports;
541 	temp = 1 + (ohci->num_ports / 8);
542 	desc->bDescLength = 7 + 2 * temp;
543 
544 	temp = 0;
545 	if (rh & RH_A_NPS)		/* no power switching? */
546 	    temp |= 0x0002;
547 	if (rh & RH_A_PSM)		/* per-port power switching? */
548 	    temp |= 0x0001;
549 	if (rh & RH_A_NOCP)		/* no overcurrent reporting? */
550 	    temp |= 0x0010;
551 	else if (rh & RH_A_OCPM)	/* per-port overcurrent reporting? */
552 	    temp |= 0x0008;
553 	desc->wHubCharacteristics = cpu_to_le16(temp);
554 
555 	/* ports removable, and usb 1.0 legacy PortPwrCtrlMask */
556 	rh = roothub_b (ohci);
557 	memset(desc->u.hs.DeviceRemovable, 0xff,
558 			sizeof(desc->u.hs.DeviceRemovable));
559 	desc->u.hs.DeviceRemovable[0] = rh & RH_B_DR;
560 	if (ohci->num_ports > 7) {
561 		desc->u.hs.DeviceRemovable[1] = (rh & RH_B_DR) >> 8;
562 		desc->u.hs.DeviceRemovable[2] = 0xff;
563 	} else
564 		desc->u.hs.DeviceRemovable[1] = 0xff;
565 }
566 
567 /*-------------------------------------------------------------------------*/
568 
569 #ifdef	CONFIG_USB_OTG
570 
571 static int ohci_start_port_reset (struct usb_hcd *hcd, unsigned port)
572 {
573 	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
574 	u32			status;
575 
576 	if (!port)
577 		return -EINVAL;
578 	port--;
579 
580 	/* start port reset before HNP protocol times out */
581 	status = ohci_readl(ohci, &ohci->regs->roothub.portstatus [port]);
582 	if (!(status & RH_PS_CCS))
583 		return -ENODEV;
584 
585 	/* khubd will finish the reset later */
586 	ohci_writel(ohci, RH_PS_PRS, &ohci->regs->roothub.portstatus [port]);
587 	return 0;
588 }
589 
590 #else
591 
592 #define	ohci_start_port_reset		NULL
593 
594 #endif
595 
596 /*-------------------------------------------------------------------------*/
597 
598 
599 /* See usb 7.1.7.5:  root hubs must issue at least 50 msec reset signaling,
600  * not necessarily continuous ... to guard against resume signaling.
601  */
602 #define	PORT_RESET_MSEC		50
603 
604 /* this timer value might be vendor-specific ... */
605 #define	PORT_RESET_HW_MSEC	10
606 
607 /* wrap-aware logic morphed from <linux/jiffies.h> */
608 #define tick_before(t1,t2) ((s16)(((s16)(t1))-((s16)(t2))) < 0)
609 
610 /* called from some task, normally khubd */
611 static inline int root_port_reset (struct ohci_hcd *ohci, unsigned port)
612 {
613 	__hc32 __iomem *portstat = &ohci->regs->roothub.portstatus [port];
614 	u32	temp = 0;
615 	u16	now = ohci_readl(ohci, &ohci->regs->fmnumber);
616 	u16	reset_done = now + PORT_RESET_MSEC;
617 	int	limit_1 = DIV_ROUND_UP(PORT_RESET_MSEC, PORT_RESET_HW_MSEC);
618 
619 	/* build a "continuous enough" reset signal, with up to
620 	 * 3msec gap between pulses.  scheduler HZ==100 must work;
621 	 * this might need to be deadline-scheduled.
622 	 */
623 	do {
624 		int limit_2;
625 
626 		/* spin until any current reset finishes */
627 		limit_2 = PORT_RESET_HW_MSEC * 2;
628 		while (--limit_2 >= 0) {
629 			temp = ohci_readl (ohci, portstat);
630 			/* handle e.g. CardBus eject */
631 			if (temp == ~(u32)0)
632 				return -ESHUTDOWN;
633 			if (!(temp & RH_PS_PRS))
634 				break;
635 			udelay (500);
636 		}
637 
638 		/* timeout (a hardware error) has been observed when
639 		 * EHCI sets CF while this driver is resetting a port;
640 		 * presumably other disconnect paths might do it too.
641 		 */
642 		if (limit_2 < 0) {
643 			ohci_dbg(ohci,
644 				"port[%d] reset timeout, stat %08x\n",
645 				port, temp);
646 			break;
647 		}
648 
649 		if (!(temp & RH_PS_CCS))
650 			break;
651 		if (temp & RH_PS_PRSC)
652 			ohci_writel (ohci, RH_PS_PRSC, portstat);
653 
654 		/* start the next reset, sleep till it's probably done */
655 		ohci_writel (ohci, RH_PS_PRS, portstat);
656 		msleep(PORT_RESET_HW_MSEC);
657 		now = ohci_readl(ohci, &ohci->regs->fmnumber);
658 	} while (tick_before(now, reset_done) && --limit_1 >= 0);
659 
660 	/* caller synchronizes using PRSC ... and handles PRS
661 	 * still being set when this returns.
662 	 */
663 
664 	return 0;
665 }
666 
667 int ohci_hub_control(
668 	struct usb_hcd	*hcd,
669 	u16		typeReq,
670 	u16		wValue,
671 	u16		wIndex,
672 	char		*buf,
673 	u16		wLength
674 ) {
675 	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
676 	int		ports = ohci->num_ports;
677 	u32		temp;
678 	int		retval = 0;
679 
680 	if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
681 		return -ESHUTDOWN;
682 
683 	switch (typeReq) {
684 	case ClearHubFeature:
685 		switch (wValue) {
686 		case C_HUB_OVER_CURRENT:
687 			ohci_writel (ohci, RH_HS_OCIC,
688 					&ohci->regs->roothub.status);
689 		case C_HUB_LOCAL_POWER:
690 			break;
691 		default:
692 			goto error;
693 		}
694 		break;
695 	case ClearPortFeature:
696 		if (!wIndex || wIndex > ports)
697 			goto error;
698 		wIndex--;
699 
700 		switch (wValue) {
701 		case USB_PORT_FEAT_ENABLE:
702 			temp = RH_PS_CCS;
703 			break;
704 		case USB_PORT_FEAT_C_ENABLE:
705 			temp = RH_PS_PESC;
706 			break;
707 		case USB_PORT_FEAT_SUSPEND:
708 			temp = RH_PS_POCI;
709 			break;
710 		case USB_PORT_FEAT_C_SUSPEND:
711 			temp = RH_PS_PSSC;
712 			break;
713 		case USB_PORT_FEAT_POWER:
714 			temp = RH_PS_LSDA;
715 			break;
716 		case USB_PORT_FEAT_C_CONNECTION:
717 			temp = RH_PS_CSC;
718 			break;
719 		case USB_PORT_FEAT_C_OVER_CURRENT:
720 			temp = RH_PS_OCIC;
721 			break;
722 		case USB_PORT_FEAT_C_RESET:
723 			temp = RH_PS_PRSC;
724 			break;
725 		default:
726 			goto error;
727 		}
728 		ohci_writel (ohci, temp,
729 				&ohci->regs->roothub.portstatus [wIndex]);
730 		// ohci_readl (ohci, &ohci->regs->roothub.portstatus [wIndex]);
731 		break;
732 	case GetHubDescriptor:
733 		ohci_hub_descriptor (ohci, (struct usb_hub_descriptor *) buf);
734 		break;
735 	case GetHubStatus:
736 		temp = roothub_status (ohci) & ~(RH_HS_CRWE | RH_HS_DRWE);
737 		put_unaligned_le32(temp, buf);
738 		break;
739 	case GetPortStatus:
740 		if (!wIndex || wIndex > ports)
741 			goto error;
742 		wIndex--;
743 		temp = roothub_portstatus (ohci, wIndex);
744 		put_unaligned_le32(temp, buf);
745 
746 		if (*(u16*)(buf+2))	/* only if wPortChange is interesting */
747 			dbg_port(ohci, "GetStatus", wIndex, temp);
748 		break;
749 	case SetHubFeature:
750 		switch (wValue) {
751 		case C_HUB_OVER_CURRENT:
752 			// FIXME:  this can be cleared, yes?
753 		case C_HUB_LOCAL_POWER:
754 			break;
755 		default:
756 			goto error;
757 		}
758 		break;
759 	case SetPortFeature:
760 		if (!wIndex || wIndex > ports)
761 			goto error;
762 		wIndex--;
763 		switch (wValue) {
764 		case USB_PORT_FEAT_SUSPEND:
765 #ifdef	CONFIG_USB_OTG
766 			if (hcd->self.otg_port == (wIndex + 1)
767 					&& hcd->self.b_hnp_enable)
768 				ohci->start_hnp(ohci);
769 			else
770 #endif
771 			ohci_writel (ohci, RH_PS_PSS,
772 				&ohci->regs->roothub.portstatus [wIndex]);
773 			break;
774 		case USB_PORT_FEAT_POWER:
775 			ohci_writel (ohci, RH_PS_PPS,
776 				&ohci->regs->roothub.portstatus [wIndex]);
777 			break;
778 		case USB_PORT_FEAT_RESET:
779 			retval = root_port_reset (ohci, wIndex);
780 			break;
781 		default:
782 			goto error;
783 		}
784 		break;
785 
786 	default:
787 error:
788 		/* "protocol stall" on error */
789 		retval = -EPIPE;
790 	}
791 	return retval;
792 }
793 EXPORT_SYMBOL_GPL(ohci_hub_control);
794