xref: /openbmc/linux/drivers/usb/host/ohci-hub.c (revision 95e9fd10)
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 	/* maybe resume can wake root hub */
94 	if (ohci_to_hcd(ohci)->self.root_hub->do_remote_wakeup || autostop) {
95 		ohci->hc_control |= OHCI_CTRL_RWE;
96 	} else {
97 		ohci_writel(ohci, OHCI_INTR_RHSC | OHCI_INTR_RD,
98 				&ohci->regs->intrdisable);
99 		ohci->hc_control &= ~OHCI_CTRL_RWE;
100 	}
101 
102 	/* Suspend hub ... this is the "global (to this bus) suspend" mode,
103 	 * which doesn't imply ports will first be individually suspended.
104 	 */
105 	ohci->hc_control &= ~OHCI_CTRL_HCFS;
106 	ohci->hc_control |= OHCI_USB_SUSPEND;
107 	ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
108 	(void) ohci_readl (ohci, &ohci->regs->control);
109 
110 	/* no resumes until devices finish suspending */
111 	if (!autostop) {
112 		ohci->next_statechange = jiffies + msecs_to_jiffies (5);
113 		ohci->autostop = 0;
114 		ohci->rh_state = OHCI_RH_SUSPENDED;
115 	}
116 
117 done:
118 	return status;
119 }
120 
121 static inline struct ed *find_head (struct ed *ed)
122 {
123 	/* for bulk and control lists */
124 	while (ed->ed_prev)
125 		ed = ed->ed_prev;
126 	return ed;
127 }
128 
129 /* caller has locked the root hub */
130 static int ohci_rh_resume (struct ohci_hcd *ohci)
131 __releases(ohci->lock)
132 __acquires(ohci->lock)
133 {
134 	struct usb_hcd		*hcd = ohci_to_hcd (ohci);
135 	u32			temp, enables;
136 	int			status = -EINPROGRESS;
137 	int			autostopped = ohci->autostop;
138 
139 	ohci->autostop = 0;
140 	ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
141 
142 	if (ohci->hc_control & (OHCI_CTRL_IR | OHCI_SCHED_ENABLES)) {
143 		/* this can happen after resuming a swsusp snapshot */
144 		if (ohci->rh_state != OHCI_RH_RUNNING) {
145 			ohci_dbg (ohci, "BIOS/SMM active, control %03x\n",
146 					ohci->hc_control);
147 			status = -EBUSY;
148 		/* this happens when pmcore resumes HC then root */
149 		} else {
150 			ohci_dbg (ohci, "duplicate resume\n");
151 			status = 0;
152 		}
153 	} else switch (ohci->hc_control & OHCI_CTRL_HCFS) {
154 	case OHCI_USB_SUSPEND:
155 		ohci->hc_control &= ~(OHCI_CTRL_HCFS|OHCI_SCHED_ENABLES);
156 		ohci->hc_control |= OHCI_USB_RESUME;
157 		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
158 		(void) ohci_readl (ohci, &ohci->regs->control);
159 		ohci_dbg (ohci, "%s root hub\n",
160 				autostopped ? "auto-start" : "resume");
161 		break;
162 	case OHCI_USB_RESUME:
163 		/* HCFS changes sometime after INTR_RD */
164 		ohci_dbg(ohci, "%swakeup root hub\n",
165 				autostopped ? "auto-" : "");
166 		break;
167 	case OHCI_USB_OPER:
168 		/* this can happen after resuming a swsusp snapshot */
169 		ohci_dbg (ohci, "snapshot resume? reinit\n");
170 		status = -EBUSY;
171 		break;
172 	default:		/* RESET, we lost power */
173 		ohci_dbg (ohci, "lost power\n");
174 		status = -EBUSY;
175 	}
176 	if (status == -EBUSY) {
177 		if (!autostopped) {
178 			spin_unlock_irq (&ohci->lock);
179 			(void) ohci_init (ohci);
180 			status = ohci_restart (ohci);
181 
182 			usb_root_hub_lost_power(hcd->self.root_hub);
183 
184 			spin_lock_irq (&ohci->lock);
185 		}
186 		return status;
187 	}
188 	if (status != -EINPROGRESS)
189 		return status;
190 	if (autostopped)
191 		goto skip_resume;
192 	spin_unlock_irq (&ohci->lock);
193 
194 	/* Some controllers (lucent erratum) need extra-long delays */
195 	msleep (20 /* usb 11.5.1.10 */ + 12 /* 32 msec counter */ + 1);
196 
197 	temp = ohci_readl (ohci, &ohci->regs->control);
198 	temp &= OHCI_CTRL_HCFS;
199 	if (temp != OHCI_USB_RESUME) {
200 		ohci_err (ohci, "controller won't resume\n");
201 		spin_lock_irq(&ohci->lock);
202 		return -EBUSY;
203 	}
204 
205 	/* disable old schedule state, reinit from scratch */
206 	ohci_writel (ohci, 0, &ohci->regs->ed_controlhead);
207 	ohci_writel (ohci, 0, &ohci->regs->ed_controlcurrent);
208 	ohci_writel (ohci, 0, &ohci->regs->ed_bulkhead);
209 	ohci_writel (ohci, 0, &ohci->regs->ed_bulkcurrent);
210 	ohci_writel (ohci, 0, &ohci->regs->ed_periodcurrent);
211 	ohci_writel (ohci, (u32) ohci->hcca_dma, &ohci->regs->hcca);
212 
213 	/* Sometimes PCI D3 suspend trashes frame timings ... */
214 	periodic_reinit (ohci);
215 
216 	/* the following code is executed with ohci->lock held and
217 	 * irqs disabled if and only if autostopped is true
218 	 */
219 
220 skip_resume:
221 	/* interrupts might have been disabled */
222 	ohci_writel (ohci, OHCI_INTR_INIT, &ohci->regs->intrenable);
223 	if (ohci->ed_rm_list)
224 		ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrenable);
225 
226 	/* Then re-enable operations */
227 	ohci_writel (ohci, OHCI_USB_OPER, &ohci->regs->control);
228 	(void) ohci_readl (ohci, &ohci->regs->control);
229 	if (!autostopped)
230 		msleep (3);
231 
232 	temp = ohci->hc_control;
233 	temp &= OHCI_CTRL_RWC;
234 	temp |= OHCI_CONTROL_INIT | OHCI_USB_OPER;
235 	ohci->hc_control = temp;
236 	ohci_writel (ohci, temp, &ohci->regs->control);
237 	(void) ohci_readl (ohci, &ohci->regs->control);
238 
239 	/* TRSMRCY */
240 	if (!autostopped) {
241 		msleep (10);
242 		spin_lock_irq (&ohci->lock);
243 	}
244 	/* now ohci->lock is always held and irqs are always disabled */
245 
246 	/* keep it alive for more than ~5x suspend + resume costs */
247 	ohci->next_statechange = jiffies + STATECHANGE_DELAY;
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 	ohci->rh_state = OHCI_RH_RUNNING;
279 	return 0;
280 }
281 
282 static int ohci_bus_suspend (struct usb_hcd *hcd)
283 {
284 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
285 	int			rc;
286 
287 	spin_lock_irq (&ohci->lock);
288 
289 	if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
290 		rc = -ESHUTDOWN;
291 	else
292 		rc = ohci_rh_suspend (ohci, 0);
293 	spin_unlock_irq (&ohci->lock);
294 	return rc;
295 }
296 
297 static int ohci_bus_resume (struct usb_hcd *hcd)
298 {
299 	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
300 	int			rc;
301 
302 	if (time_before (jiffies, ohci->next_statechange))
303 		msleep(5);
304 
305 	spin_lock_irq (&ohci->lock);
306 
307 	if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
308 		rc = -ESHUTDOWN;
309 	else
310 		rc = ohci_rh_resume (ohci);
311 	spin_unlock_irq (&ohci->lock);
312 
313 	/* poll until we know a device is connected or we autostop */
314 	if (rc == 0)
315 		usb_hcd_poll_rh_status(hcd);
316 	return rc;
317 }
318 
319 /* Carry out the final steps of resuming the controller device */
320 static void __maybe_unused ohci_finish_controller_resume(struct usb_hcd *hcd)
321 {
322 	struct ohci_hcd		*ohci = hcd_to_ohci(hcd);
323 	int			port;
324 	bool			need_reinit = false;
325 
326 	/* See if the controller is already running or has been reset */
327 	ohci->hc_control = ohci_readl(ohci, &ohci->regs->control);
328 	if (ohci->hc_control & (OHCI_CTRL_IR | OHCI_SCHED_ENABLES)) {
329 		need_reinit = true;
330 	} else {
331 		switch (ohci->hc_control & OHCI_CTRL_HCFS) {
332 		case OHCI_USB_OPER:
333 		case OHCI_USB_RESET:
334 			need_reinit = true;
335 		}
336 	}
337 
338 	/* If needed, reinitialize and suspend the root hub */
339 	if (need_reinit) {
340 		spin_lock_irq(&ohci->lock);
341 		ohci_rh_resume(ohci);
342 		ohci_rh_suspend(ohci, 0);
343 		spin_unlock_irq(&ohci->lock);
344 	}
345 
346 	/* Normally just turn on port power and enable interrupts */
347 	else {
348 		ohci_dbg(ohci, "powerup ports\n");
349 		for (port = 0; port < ohci->num_ports; port++)
350 			ohci_writel(ohci, RH_PS_PPS,
351 					&ohci->regs->roothub.portstatus[port]);
352 
353 		ohci_writel(ohci, OHCI_INTR_MIE, &ohci->regs->intrenable);
354 		ohci_readl(ohci, &ohci->regs->intrenable);
355 		msleep(20);
356 	}
357 
358 	usb_hcd_resume_root_hub(hcd);
359 }
360 
361 /* Carry out polling-, autostop-, and autoresume-related state changes */
362 static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
363 		int any_connected, int rhsc_status)
364 {
365 	int	poll_rh = 1;
366 	int	rhsc_enable;
367 
368 	/* Some broken controllers never turn off RHSC in the interrupt
369 	 * status register.  For their sake we won't re-enable RHSC
370 	 * interrupts if the interrupt bit is already active.
371 	 */
372 	rhsc_enable = ohci_readl(ohci, &ohci->regs->intrenable) &
373 			OHCI_INTR_RHSC;
374 
375 	switch (ohci->hc_control & OHCI_CTRL_HCFS) {
376 	case OHCI_USB_OPER:
377 		/* If no status changes are pending, enable RHSC interrupts. */
378 		if (!rhsc_enable && !rhsc_status && !changed) {
379 			rhsc_enable = OHCI_INTR_RHSC;
380 			ohci_writel(ohci, rhsc_enable, &ohci->regs->intrenable);
381 		}
382 
383 		/* Keep on polling until we know a device is connected
384 		 * and RHSC is enabled, or until we autostop.
385 		 */
386 		if (!ohci->autostop) {
387 			if (any_connected ||
388 					!device_may_wakeup(&ohci_to_hcd(ohci)
389 						->self.root_hub->dev)) {
390 				if (rhsc_enable)
391 					poll_rh = 0;
392 			} else {
393 				ohci->autostop = 1;
394 				ohci->next_statechange = jiffies + HZ;
395 			}
396 
397 		/* if no devices have been attached for one second, autostop */
398 		} else {
399 			if (changed || any_connected) {
400 				ohci->autostop = 0;
401 				ohci->next_statechange = jiffies +
402 						STATECHANGE_DELAY;
403 			} else if (time_after_eq(jiffies,
404 						ohci->next_statechange)
405 					&& !ohci->ed_rm_list
406 					&& !(ohci->hc_control &
407 						OHCI_SCHED_ENABLES)) {
408 				ohci_rh_suspend(ohci, 1);
409 				if (rhsc_enable)
410 					poll_rh = 0;
411 			}
412 		}
413 		break;
414 
415 	case OHCI_USB_SUSPEND:
416 	case OHCI_USB_RESUME:
417 		/* if there is a port change, autostart or ask to be resumed */
418 		if (changed) {
419 			if (ohci->autostop)
420 				ohci_rh_resume(ohci);
421 			else
422 				usb_hcd_resume_root_hub(ohci_to_hcd(ohci));
423 
424 		/* If remote wakeup is disabled, stop polling */
425 		} else if (!ohci->autostop &&
426 				!ohci_to_hcd(ohci)->self.root_hub->
427 					do_remote_wakeup) {
428 			poll_rh = 0;
429 
430 		} else {
431 			/* If no status changes are pending,
432 			 * enable RHSC interrupts
433 			 */
434 			if (!rhsc_enable && !rhsc_status) {
435 				rhsc_enable = OHCI_INTR_RHSC;
436 				ohci_writel(ohci, rhsc_enable,
437 						&ohci->regs->intrenable);
438 			}
439 			/* Keep polling until RHSC is enabled */
440 			if (rhsc_enable)
441 				poll_rh = 0;
442 		}
443 		break;
444 	}
445 	return poll_rh;
446 }
447 
448 #else	/* CONFIG_PM */
449 
450 static inline int ohci_rh_resume(struct ohci_hcd *ohci)
451 {
452 	return 0;
453 }
454 
455 /* Carry out polling-related state changes.
456  * autostop isn't used when CONFIG_PM is turned off.
457  */
458 static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
459 		int any_connected, int rhsc_status)
460 {
461 	/* If RHSC is enabled, don't poll */
462 	if (ohci_readl(ohci, &ohci->regs->intrenable) & OHCI_INTR_RHSC)
463 		return 0;
464 
465 	/* If status changes are pending, continue polling.
466 	 * Conversely, if no status changes are pending but the RHSC
467 	 * status bit was set, then RHSC may be broken so continue polling.
468 	 */
469 	if (changed || rhsc_status)
470 		return 1;
471 
472 	/* It's safe to re-enable RHSC interrupts */
473 	ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrenable);
474 	return 0;
475 }
476 
477 #endif	/* CONFIG_PM */
478 
479 /*-------------------------------------------------------------------------*/
480 
481 /* build "status change" packet (one or two bytes) from HC registers */
482 
483 static int
484 ohci_hub_status_data (struct usb_hcd *hcd, char *buf)
485 {
486 	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
487 	int		i, changed = 0, length = 1;
488 	int		any_connected = 0;
489 	int		rhsc_status;
490 	unsigned long	flags;
491 
492 	spin_lock_irqsave (&ohci->lock, flags);
493 	if (!HCD_HW_ACCESSIBLE(hcd))
494 		goto done;
495 
496 	/* undocumented erratum seen on at least rev D */
497 	if ((ohci->flags & OHCI_QUIRK_AMD756)
498 			&& (roothub_a (ohci) & RH_A_NDP) > MAX_ROOT_PORTS) {
499 		ohci_warn (ohci, "bogus NDP, rereads as NDP=%d\n",
500 			  ohci_readl (ohci, &ohci->regs->roothub.a) & RH_A_NDP);
501 		/* retry later; "should not happen" */
502 		goto done;
503 	}
504 
505 	/* init status */
506 	if (roothub_status (ohci) & (RH_HS_LPSC | RH_HS_OCIC))
507 		buf [0] = changed = 1;
508 	else
509 		buf [0] = 0;
510 	if (ohci->num_ports > 7) {
511 		buf [1] = 0;
512 		length++;
513 	}
514 
515 	/* Clear the RHSC status flag before reading the port statuses */
516 	ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrstatus);
517 	rhsc_status = ohci_readl(ohci, &ohci->regs->intrstatus) &
518 			OHCI_INTR_RHSC;
519 
520 	/* look at each port */
521 	for (i = 0; i < ohci->num_ports; i++) {
522 		u32	status = roothub_portstatus (ohci, i);
523 
524 		/* can't autostop if ports are connected */
525 		any_connected |= (status & RH_PS_CCS);
526 
527 		if (status & (RH_PS_CSC | RH_PS_PESC | RH_PS_PSSC
528 				| RH_PS_OCIC | RH_PS_PRSC)) {
529 			changed = 1;
530 			if (i < 7)
531 			    buf [0] |= 1 << (i + 1);
532 			else
533 			    buf [1] |= 1 << (i - 7);
534 		}
535 	}
536 
537 	if (ohci_root_hub_state_changes(ohci, changed,
538 			any_connected, rhsc_status))
539 		set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
540 	else
541 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
542 
543 
544 done:
545 	spin_unlock_irqrestore (&ohci->lock, flags);
546 
547 	return changed ? length : 0;
548 }
549 
550 /*-------------------------------------------------------------------------*/
551 
552 static void
553 ohci_hub_descriptor (
554 	struct ohci_hcd			*ohci,
555 	struct usb_hub_descriptor	*desc
556 ) {
557 	u32		rh = roothub_a (ohci);
558 	u16		temp;
559 
560 	desc->bDescriptorType = 0x29;
561 	desc->bPwrOn2PwrGood = (rh & RH_A_POTPGT) >> 24;
562 	desc->bHubContrCurrent = 0;
563 
564 	desc->bNbrPorts = ohci->num_ports;
565 	temp = 1 + (ohci->num_ports / 8);
566 	desc->bDescLength = 7 + 2 * temp;
567 
568 	temp = 0;
569 	if (rh & RH_A_NPS)		/* no power switching? */
570 	    temp |= 0x0002;
571 	if (rh & RH_A_PSM)		/* per-port power switching? */
572 	    temp |= 0x0001;
573 	if (rh & RH_A_NOCP)		/* no overcurrent reporting? */
574 	    temp |= 0x0010;
575 	else if (rh & RH_A_OCPM)	/* per-port overcurrent reporting? */
576 	    temp |= 0x0008;
577 	desc->wHubCharacteristics = (__force __u16)cpu_to_hc16(ohci, temp);
578 
579 	/* ports removable, and usb 1.0 legacy PortPwrCtrlMask */
580 	rh = roothub_b (ohci);
581 	memset(desc->u.hs.DeviceRemovable, 0xff,
582 			sizeof(desc->u.hs.DeviceRemovable));
583 	desc->u.hs.DeviceRemovable[0] = rh & RH_B_DR;
584 	if (ohci->num_ports > 7) {
585 		desc->u.hs.DeviceRemovable[1] = (rh & RH_B_DR) >> 8;
586 		desc->u.hs.DeviceRemovable[2] = 0xff;
587 	} else
588 		desc->u.hs.DeviceRemovable[1] = 0xff;
589 }
590 
591 /*-------------------------------------------------------------------------*/
592 
593 #ifdef	CONFIG_USB_OTG
594 
595 static int ohci_start_port_reset (struct usb_hcd *hcd, unsigned port)
596 {
597 	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
598 	u32			status;
599 
600 	if (!port)
601 		return -EINVAL;
602 	port--;
603 
604 	/* start port reset before HNP protocol times out */
605 	status = ohci_readl(ohci, &ohci->regs->roothub.portstatus [port]);
606 	if (!(status & RH_PS_CCS))
607 		return -ENODEV;
608 
609 	/* khubd will finish the reset later */
610 	ohci_writel(ohci, RH_PS_PRS, &ohci->regs->roothub.portstatus [port]);
611 	return 0;
612 }
613 
614 #else
615 
616 #define	ohci_start_port_reset		NULL
617 
618 #endif
619 
620 /*-------------------------------------------------------------------------*/
621 
622 
623 /* See usb 7.1.7.5:  root hubs must issue at least 50 msec reset signaling,
624  * not necessarily continuous ... to guard against resume signaling.
625  * The short timeout is safe for non-root hubs, and is backward-compatible
626  * with earlier Linux hosts.
627  */
628 #ifdef	CONFIG_USB_SUSPEND
629 #define	PORT_RESET_MSEC		50
630 #else
631 #define	PORT_RESET_MSEC		10
632 #endif
633 
634 /* this timer value might be vendor-specific ... */
635 #define	PORT_RESET_HW_MSEC	10
636 
637 /* wrap-aware logic morphed from <linux/jiffies.h> */
638 #define tick_before(t1,t2) ((s16)(((s16)(t1))-((s16)(t2))) < 0)
639 
640 /* called from some task, normally khubd */
641 static inline int root_port_reset (struct ohci_hcd *ohci, unsigned port)
642 {
643 	__hc32 __iomem *portstat = &ohci->regs->roothub.portstatus [port];
644 	u32	temp = 0;
645 	u16	now = ohci_readl(ohci, &ohci->regs->fmnumber);
646 	u16	reset_done = now + PORT_RESET_MSEC;
647 	int	limit_1 = DIV_ROUND_UP(PORT_RESET_MSEC, PORT_RESET_HW_MSEC);
648 
649 	/* build a "continuous enough" reset signal, with up to
650 	 * 3msec gap between pulses.  scheduler HZ==100 must work;
651 	 * this might need to be deadline-scheduled.
652 	 */
653 	do {
654 		int limit_2;
655 
656 		/* spin until any current reset finishes */
657 		limit_2 = PORT_RESET_HW_MSEC * 2;
658 		while (--limit_2 >= 0) {
659 			temp = ohci_readl (ohci, portstat);
660 			/* handle e.g. CardBus eject */
661 			if (temp == ~(u32)0)
662 				return -ESHUTDOWN;
663 			if (!(temp & RH_PS_PRS))
664 				break;
665 			udelay (500);
666 		}
667 
668 		/* timeout (a hardware error) has been observed when
669 		 * EHCI sets CF while this driver is resetting a port;
670 		 * presumably other disconnect paths might do it too.
671 		 */
672 		if (limit_2 < 0) {
673 			ohci_dbg(ohci,
674 				"port[%d] reset timeout, stat %08x\n",
675 				port, temp);
676 			break;
677 		}
678 
679 		if (!(temp & RH_PS_CCS))
680 			break;
681 		if (temp & RH_PS_PRSC)
682 			ohci_writel (ohci, RH_PS_PRSC, portstat);
683 
684 		/* start the next reset, sleep till it's probably done */
685 		ohci_writel (ohci, RH_PS_PRS, portstat);
686 		msleep(PORT_RESET_HW_MSEC);
687 		now = ohci_readl(ohci, &ohci->regs->fmnumber);
688 	} while (tick_before(now, reset_done) && --limit_1 >= 0);
689 
690 	/* caller synchronizes using PRSC ... and handles PRS
691 	 * still being set when this returns.
692 	 */
693 
694 	return 0;
695 }
696 
697 static int ohci_hub_control (
698 	struct usb_hcd	*hcd,
699 	u16		typeReq,
700 	u16		wValue,
701 	u16		wIndex,
702 	char		*buf,
703 	u16		wLength
704 ) {
705 	struct ohci_hcd	*ohci = hcd_to_ohci (hcd);
706 	int		ports = ohci->num_ports;
707 	u32		temp;
708 	int		retval = 0;
709 
710 	if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
711 		return -ESHUTDOWN;
712 
713 	switch (typeReq) {
714 	case ClearHubFeature:
715 		switch (wValue) {
716 		case C_HUB_OVER_CURRENT:
717 			ohci_writel (ohci, RH_HS_OCIC,
718 					&ohci->regs->roothub.status);
719 		case C_HUB_LOCAL_POWER:
720 			break;
721 		default:
722 			goto error;
723 		}
724 		break;
725 	case ClearPortFeature:
726 		if (!wIndex || wIndex > ports)
727 			goto error;
728 		wIndex--;
729 
730 		switch (wValue) {
731 		case USB_PORT_FEAT_ENABLE:
732 			temp = RH_PS_CCS;
733 			break;
734 		case USB_PORT_FEAT_C_ENABLE:
735 			temp = RH_PS_PESC;
736 			break;
737 		case USB_PORT_FEAT_SUSPEND:
738 			temp = RH_PS_POCI;
739 			break;
740 		case USB_PORT_FEAT_C_SUSPEND:
741 			temp = RH_PS_PSSC;
742 			break;
743 		case USB_PORT_FEAT_POWER:
744 			temp = RH_PS_LSDA;
745 			break;
746 		case USB_PORT_FEAT_C_CONNECTION:
747 			temp = RH_PS_CSC;
748 			break;
749 		case USB_PORT_FEAT_C_OVER_CURRENT:
750 			temp = RH_PS_OCIC;
751 			break;
752 		case USB_PORT_FEAT_C_RESET:
753 			temp = RH_PS_PRSC;
754 			break;
755 		default:
756 			goto error;
757 		}
758 		ohci_writel (ohci, temp,
759 				&ohci->regs->roothub.portstatus [wIndex]);
760 		// ohci_readl (ohci, &ohci->regs->roothub.portstatus [wIndex]);
761 		break;
762 	case GetHubDescriptor:
763 		ohci_hub_descriptor (ohci, (struct usb_hub_descriptor *) buf);
764 		break;
765 	case GetHubStatus:
766 		temp = roothub_status (ohci) & ~(RH_HS_CRWE | RH_HS_DRWE);
767 		put_unaligned_le32(temp, buf);
768 		break;
769 	case GetPortStatus:
770 		if (!wIndex || wIndex > ports)
771 			goto error;
772 		wIndex--;
773 		temp = roothub_portstatus (ohci, wIndex);
774 		put_unaligned_le32(temp, buf);
775 
776 #ifndef	OHCI_VERBOSE_DEBUG
777 	if (*(u16*)(buf+2))	/* only if wPortChange is interesting */
778 #endif
779 		dbg_port (ohci, "GetStatus", wIndex, temp);
780 		break;
781 	case SetHubFeature:
782 		switch (wValue) {
783 		case C_HUB_OVER_CURRENT:
784 			// FIXME:  this can be cleared, yes?
785 		case C_HUB_LOCAL_POWER:
786 			break;
787 		default:
788 			goto error;
789 		}
790 		break;
791 	case SetPortFeature:
792 		if (!wIndex || wIndex > ports)
793 			goto error;
794 		wIndex--;
795 		switch (wValue) {
796 		case USB_PORT_FEAT_SUSPEND:
797 #ifdef	CONFIG_USB_OTG
798 			if (hcd->self.otg_port == (wIndex + 1)
799 					&& hcd->self.b_hnp_enable)
800 				ohci->start_hnp(ohci);
801 			else
802 #endif
803 			ohci_writel (ohci, RH_PS_PSS,
804 				&ohci->regs->roothub.portstatus [wIndex]);
805 			break;
806 		case USB_PORT_FEAT_POWER:
807 			ohci_writel (ohci, RH_PS_PPS,
808 				&ohci->regs->roothub.portstatus [wIndex]);
809 			break;
810 		case USB_PORT_FEAT_RESET:
811 			retval = root_port_reset (ohci, wIndex);
812 			break;
813 		default:
814 			goto error;
815 		}
816 		break;
817 
818 	default:
819 error:
820 		/* "protocol stall" on error */
821 		retval = -EPIPE;
822 	}
823 	return retval;
824 }
825 
826