GNU Linux-libre 4.9.333-gnu1
[releases.git] / drivers / usb / host / ohci-hub.c
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 update_done_list(struct ohci_hcd *);
43 static void ohci_work(struct ohci_hcd *);
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         update_done_list(ohci);
91         ohci_work(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
313         if (rc == 0) {
314                 del_timer_sync(&ohci->io_watchdog);
315                 ohci->prev_frame_no = IO_WATCHDOG_OFF;
316         }
317         return rc;
318 }
319
320 static int ohci_bus_resume (struct usb_hcd *hcd)
321 {
322         struct ohci_hcd         *ohci = hcd_to_ohci (hcd);
323         int                     rc;
324
325         if (time_before (jiffies, ohci->next_statechange))
326                 msleep(5);
327
328         spin_lock_irq (&ohci->lock);
329
330         if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
331                 rc = -ESHUTDOWN;
332         else
333                 rc = ohci_rh_resume (ohci);
334         spin_unlock_irq (&ohci->lock);
335
336         /* poll until we know a device is connected or we autostop */
337         if (rc == 0)
338                 usb_hcd_poll_rh_status(hcd);
339         return rc;
340 }
341
342 /* Carry out polling-, autostop-, and autoresume-related state changes */
343 static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
344                 int any_connected, int rhsc_status)
345 {
346         int     poll_rh = 1;
347         int     rhsc_enable;
348
349         /* Some broken controllers never turn off RHSC in the interrupt
350          * status register.  For their sake we won't re-enable RHSC
351          * interrupts if the interrupt bit is already active.
352          */
353         rhsc_enable = ohci_readl(ohci, &ohci->regs->intrenable) &
354                         OHCI_INTR_RHSC;
355
356         switch (ohci->hc_control & OHCI_CTRL_HCFS) {
357         case OHCI_USB_OPER:
358                 /* If no status changes are pending, enable RHSC interrupts. */
359                 if (!rhsc_enable && !rhsc_status && !changed) {
360                         rhsc_enable = OHCI_INTR_RHSC;
361                         ohci_writel(ohci, rhsc_enable, &ohci->regs->intrenable);
362                 }
363
364                 /* Keep on polling until we know a device is connected
365                  * and RHSC is enabled, or until we autostop.
366                  */
367                 if (!ohci->autostop) {
368                         if (any_connected ||
369                                         !device_may_wakeup(&ohci_to_hcd(ohci)
370                                                 ->self.root_hub->dev)) {
371                                 if (rhsc_enable)
372                                         poll_rh = 0;
373                         } else {
374                                 ohci->autostop = 1;
375                                 ohci->next_statechange = jiffies + HZ;
376                         }
377
378                 /* if no devices have been attached for one second, autostop */
379                 } else {
380                         if (changed || any_connected) {
381                                 ohci->autostop = 0;
382                                 ohci->next_statechange = jiffies +
383                                                 STATECHANGE_DELAY;
384                         } else if (time_after_eq(jiffies,
385                                                 ohci->next_statechange)
386                                         && !ohci->ed_rm_list
387                                         && !(ohci->hc_control &
388                                                 OHCI_SCHED_ENABLES)) {
389                                 ohci_rh_suspend(ohci, 1);
390                                 if (rhsc_enable)
391                                         poll_rh = 0;
392                         }
393                 }
394                 break;
395
396         case OHCI_USB_SUSPEND:
397         case OHCI_USB_RESUME:
398                 /* if there is a port change, autostart or ask to be resumed */
399                 if (changed) {
400                         if (ohci->autostop)
401                                 ohci_rh_resume(ohci);
402                         else
403                                 usb_hcd_resume_root_hub(ohci_to_hcd(ohci));
404
405                 /* If remote wakeup is disabled, stop polling */
406                 } else if (!ohci->autostop &&
407                                 !ohci_to_hcd(ohci)->self.root_hub->
408                                         do_remote_wakeup) {
409                         poll_rh = 0;
410
411                 } else {
412                         /* If no status changes are pending,
413                          * enable RHSC interrupts
414                          */
415                         if (!rhsc_enable && !rhsc_status) {
416                                 rhsc_enable = OHCI_INTR_RHSC;
417                                 ohci_writel(ohci, rhsc_enable,
418                                                 &ohci->regs->intrenable);
419                         }
420                         /* Keep polling until RHSC is enabled */
421                         if (rhsc_enable)
422                                 poll_rh = 0;
423                 }
424                 break;
425         }
426         return poll_rh;
427 }
428
429 #else   /* CONFIG_PM */
430
431 static inline int ohci_rh_resume(struct ohci_hcd *ohci)
432 {
433         return 0;
434 }
435
436 /* Carry out polling-related state changes.
437  * autostop isn't used when CONFIG_PM is turned off.
438  */
439 static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
440                 int any_connected, int rhsc_status)
441 {
442         /* If RHSC is enabled, don't poll */
443         if (ohci_readl(ohci, &ohci->regs->intrenable) & OHCI_INTR_RHSC)
444                 return 0;
445
446         /* If status changes are pending, continue polling.
447          * Conversely, if no status changes are pending but the RHSC
448          * status bit was set, then RHSC may be broken so continue polling.
449          */
450         if (changed || rhsc_status)
451                 return 1;
452
453         /* It's safe to re-enable RHSC interrupts */
454         ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrenable);
455         return 0;
456 }
457
458 #endif  /* CONFIG_PM */
459
460 /*-------------------------------------------------------------------------*/
461
462 /* build "status change" packet (one or two bytes) from HC registers */
463
464 int ohci_hub_status_data(struct usb_hcd *hcd, char *buf)
465 {
466         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
467         int             i, changed = 0, length = 1;
468         int             any_connected = 0;
469         int             rhsc_status;
470         unsigned long   flags;
471
472         spin_lock_irqsave (&ohci->lock, flags);
473         if (!HCD_HW_ACCESSIBLE(hcd))
474                 goto done;
475
476         /* undocumented erratum seen on at least rev D */
477         if ((ohci->flags & OHCI_QUIRK_AMD756)
478                         && (roothub_a (ohci) & RH_A_NDP) > MAX_ROOT_PORTS) {
479                 ohci_warn (ohci, "bogus NDP, rereads as NDP=%d\n",
480                           ohci_readl (ohci, &ohci->regs->roothub.a) & RH_A_NDP);
481                 /* retry later; "should not happen" */
482                 goto done;
483         }
484
485         /* init status */
486         if (roothub_status (ohci) & (RH_HS_LPSC | RH_HS_OCIC))
487                 buf [0] = changed = 1;
488         else
489                 buf [0] = 0;
490         if (ohci->num_ports > 7) {
491                 buf [1] = 0;
492                 length++;
493         }
494
495         /* Clear the RHSC status flag before reading the port statuses */
496         ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrstatus);
497         rhsc_status = ohci_readl(ohci, &ohci->regs->intrstatus) &
498                         OHCI_INTR_RHSC;
499
500         /* look at each port */
501         for (i = 0; i < ohci->num_ports; i++) {
502                 u32     status = roothub_portstatus (ohci, i);
503
504                 /* can't autostop if ports are connected */
505                 any_connected |= (status & RH_PS_CCS);
506
507                 if (status & (RH_PS_CSC | RH_PS_PESC | RH_PS_PSSC
508                                 | RH_PS_OCIC | RH_PS_PRSC)) {
509                         changed = 1;
510                         if (i < 7)
511                             buf [0] |= 1 << (i + 1);
512                         else
513                             buf [1] |= 1 << (i - 7);
514                 }
515         }
516
517         if (ohci_root_hub_state_changes(ohci, changed,
518                         any_connected, rhsc_status))
519                 set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
520         else
521                 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
522
523
524 done:
525         spin_unlock_irqrestore (&ohci->lock, flags);
526
527         return changed ? length : 0;
528 }
529 EXPORT_SYMBOL_GPL(ohci_hub_status_data);
530
531 /*-------------------------------------------------------------------------*/
532
533 static void
534 ohci_hub_descriptor (
535         struct ohci_hcd                 *ohci,
536         struct usb_hub_descriptor       *desc
537 ) {
538         u32             rh = roothub_a (ohci);
539         u16             temp;
540
541         desc->bDescriptorType = USB_DT_HUB;
542         desc->bPwrOn2PwrGood = (rh & RH_A_POTPGT) >> 24;
543         desc->bHubContrCurrent = 0;
544
545         desc->bNbrPorts = ohci->num_ports;
546         temp = 1 + (ohci->num_ports / 8);
547         desc->bDescLength = 7 + 2 * temp;
548
549         temp = HUB_CHAR_COMMON_LPSM | HUB_CHAR_COMMON_OCPM;
550         if (rh & RH_A_NPS)              /* no power switching? */
551                 temp |= HUB_CHAR_NO_LPSM;
552         if (rh & RH_A_PSM)              /* per-port power switching? */
553                 temp |= HUB_CHAR_INDV_PORT_LPSM;
554         if (rh & RH_A_NOCP)             /* no overcurrent reporting? */
555                 temp |= HUB_CHAR_NO_OCPM;
556         else if (rh & RH_A_OCPM)        /* per-port overcurrent reporting? */
557                 temp |= HUB_CHAR_INDV_PORT_OCPM;
558         desc->wHubCharacteristics = cpu_to_le16(temp);
559
560         /* ports removable, and usb 1.0 legacy PortPwrCtrlMask */
561         rh = roothub_b (ohci);
562         memset(desc->u.hs.DeviceRemovable, 0xff,
563                         sizeof(desc->u.hs.DeviceRemovable));
564         desc->u.hs.DeviceRemovable[0] = rh & RH_B_DR;
565         if (ohci->num_ports > 7) {
566                 desc->u.hs.DeviceRemovable[1] = (rh & RH_B_DR) >> 8;
567                 desc->u.hs.DeviceRemovable[2] = 0xff;
568         } else
569                 desc->u.hs.DeviceRemovable[1] = 0xff;
570 }
571
572 /*-------------------------------------------------------------------------*/
573
574 #ifdef  CONFIG_USB_OTG
575
576 static int ohci_start_port_reset (struct usb_hcd *hcd, unsigned port)
577 {
578         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
579         u32                     status;
580
581         if (!port)
582                 return -EINVAL;
583         port--;
584
585         /* start port reset before HNP protocol times out */
586         status = ohci_readl(ohci, &ohci->regs->roothub.portstatus [port]);
587         if (!(status & RH_PS_CCS))
588                 return -ENODEV;
589
590         /* hub_wq will finish the reset later */
591         ohci_writel(ohci, RH_PS_PRS, &ohci->regs->roothub.portstatus [port]);
592         return 0;
593 }
594
595 #else
596
597 #define ohci_start_port_reset           NULL
598
599 #endif
600
601 /*-------------------------------------------------------------------------*/
602
603
604 /* See usb 7.1.7.5:  root hubs must issue at least 50 msec reset signaling,
605  * not necessarily continuous ... to guard against resume signaling.
606  */
607 #define PORT_RESET_MSEC         50
608
609 /* this timer value might be vendor-specific ... */
610 #define PORT_RESET_HW_MSEC      10
611
612 /* wrap-aware logic morphed from <linux/jiffies.h> */
613 #define tick_before(t1,t2) ((s16)(((s16)(t1))-((s16)(t2))) < 0)
614
615 /* called from some task, normally hub_wq */
616 static inline int root_port_reset (struct ohci_hcd *ohci, unsigned port)
617 {
618         __hc32 __iomem *portstat = &ohci->regs->roothub.portstatus [port];
619         u32     temp = 0;
620         u16     now = ohci_readl(ohci, &ohci->regs->fmnumber);
621         u16     reset_done = now + PORT_RESET_MSEC;
622         int     limit_1 = DIV_ROUND_UP(PORT_RESET_MSEC, PORT_RESET_HW_MSEC);
623
624         /* build a "continuous enough" reset signal, with up to
625          * 3msec gap between pulses.  scheduler HZ==100 must work;
626          * this might need to be deadline-scheduled.
627          */
628         do {
629                 int limit_2;
630
631                 /* spin until any current reset finishes */
632                 limit_2 = PORT_RESET_HW_MSEC * 2;
633                 while (--limit_2 >= 0) {
634                         temp = ohci_readl (ohci, portstat);
635                         /* handle e.g. CardBus eject */
636                         if (temp == ~(u32)0)
637                                 return -ESHUTDOWN;
638                         if (!(temp & RH_PS_PRS))
639                                 break;
640                         udelay (500);
641                 }
642
643                 /* timeout (a hardware error) has been observed when
644                  * EHCI sets CF while this driver is resetting a port;
645                  * presumably other disconnect paths might do it too.
646                  */
647                 if (limit_2 < 0) {
648                         ohci_dbg(ohci,
649                                 "port[%d] reset timeout, stat %08x\n",
650                                 port, temp);
651                         break;
652                 }
653
654                 if (!(temp & RH_PS_CCS))
655                         break;
656                 if (temp & RH_PS_PRSC)
657                         ohci_writel (ohci, RH_PS_PRSC, portstat);
658
659                 /* start the next reset, sleep till it's probably done */
660                 ohci_writel (ohci, RH_PS_PRS, portstat);
661                 msleep(PORT_RESET_HW_MSEC);
662                 now = ohci_readl(ohci, &ohci->regs->fmnumber);
663         } while (tick_before(now, reset_done) && --limit_1 >= 0);
664
665         /* caller synchronizes using PRSC ... and handles PRS
666          * still being set when this returns.
667          */
668
669         return 0;
670 }
671
672 int ohci_hub_control(
673         struct usb_hcd  *hcd,
674         u16             typeReq,
675         u16             wValue,
676         u16             wIndex,
677         char            *buf,
678         u16             wLength
679 ) {
680         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
681         int             ports = ohci->num_ports;
682         u32             temp;
683         int             retval = 0;
684
685         if (unlikely(!HCD_HW_ACCESSIBLE(hcd)))
686                 return -ESHUTDOWN;
687
688         switch (typeReq) {
689         case ClearHubFeature:
690                 switch (wValue) {
691                 case C_HUB_OVER_CURRENT:
692                         ohci_writel (ohci, RH_HS_OCIC,
693                                         &ohci->regs->roothub.status);
694                 case C_HUB_LOCAL_POWER:
695                         break;
696                 default:
697                         goto error;
698                 }
699                 break;
700         case ClearPortFeature:
701                 if (!wIndex || wIndex > ports)
702                         goto error;
703                 wIndex--;
704
705                 switch (wValue) {
706                 case USB_PORT_FEAT_ENABLE:
707                         temp = RH_PS_CCS;
708                         break;
709                 case USB_PORT_FEAT_C_ENABLE:
710                         temp = RH_PS_PESC;
711                         break;
712                 case USB_PORT_FEAT_SUSPEND:
713                         temp = RH_PS_POCI;
714                         break;
715                 case USB_PORT_FEAT_C_SUSPEND:
716                         temp = RH_PS_PSSC;
717                         break;
718                 case USB_PORT_FEAT_POWER:
719                         temp = RH_PS_LSDA;
720                         break;
721                 case USB_PORT_FEAT_C_CONNECTION:
722                         temp = RH_PS_CSC;
723                         break;
724                 case USB_PORT_FEAT_C_OVER_CURRENT:
725                         temp = RH_PS_OCIC;
726                         break;
727                 case USB_PORT_FEAT_C_RESET:
728                         temp = RH_PS_PRSC;
729                         break;
730                 default:
731                         goto error;
732                 }
733                 ohci_writel (ohci, temp,
734                                 &ohci->regs->roothub.portstatus [wIndex]);
735                 // ohci_readl (ohci, &ohci->regs->roothub.portstatus [wIndex]);
736                 break;
737         case GetHubDescriptor:
738                 ohci_hub_descriptor (ohci, (struct usb_hub_descriptor *) buf);
739                 break;
740         case GetHubStatus:
741                 temp = roothub_status (ohci) & ~(RH_HS_CRWE | RH_HS_DRWE);
742                 put_unaligned_le32(temp, buf);
743                 break;
744         case GetPortStatus:
745                 if (!wIndex || wIndex > ports)
746                         goto error;
747                 wIndex--;
748                 temp = roothub_portstatus (ohci, wIndex);
749                 put_unaligned_le32(temp, buf);
750
751                 if (*(u16*)(buf+2))     /* only if wPortChange is interesting */
752                         dbg_port(ohci, "GetStatus", wIndex, temp);
753                 break;
754         case SetHubFeature:
755                 switch (wValue) {
756                 case C_HUB_OVER_CURRENT:
757                         // FIXME:  this can be cleared, yes?
758                 case C_HUB_LOCAL_POWER:
759                         break;
760                 default:
761                         goto error;
762                 }
763                 break;
764         case SetPortFeature:
765                 if (!wIndex || wIndex > ports)
766                         goto error;
767                 wIndex--;
768                 switch (wValue) {
769                 case USB_PORT_FEAT_SUSPEND:
770 #ifdef  CONFIG_USB_OTG
771                         if (hcd->self.otg_port == (wIndex + 1)
772                                         && hcd->self.b_hnp_enable)
773                                 ohci->start_hnp(ohci);
774                         else
775 #endif
776                         ohci_writel (ohci, RH_PS_PSS,
777                                 &ohci->regs->roothub.portstatus [wIndex]);
778                         break;
779                 case USB_PORT_FEAT_POWER:
780                         ohci_writel (ohci, RH_PS_PPS,
781                                 &ohci->regs->roothub.portstatus [wIndex]);
782                         break;
783                 case USB_PORT_FEAT_RESET:
784                         retval = root_port_reset (ohci, wIndex);
785                         break;
786                 default:
787                         goto error;
788                 }
789                 break;
790
791         default:
792 error:
793                 /* "protocol stall" on error */
794                 retval = -EPIPE;
795         }
796         return retval;
797 }
798 EXPORT_SYMBOL_GPL(ohci_hub_control);