Linux kernel & device driver programming

Cross-Referenced Linux and Device Driver Code

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Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  1 /*
  2  * OHCI HCD (Host Controller Driver) for USB.
  3  *
  4  * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
  5  * (C) Copyright 2000-2004 David Brownell <dbrownell@users.sourceforge.net>
  6  *
  7  * This file is licenced under GPL
  8  */
  9 
 10 /*-------------------------------------------------------------------------*/
 11 
 12 /*
 13  * OHCI Root Hub ... the nonsharable stuff
 14  */
 15 
 16 #define dbg_port(hc,label,num,value) \
 17         ohci_dbg (hc, \
 18                 "%s roothub.portstatus [%d] " \
 19                 "= 0x%08x%s%s%s%s%s%s%s%s%s%s%s%s\n", \
 20                 label, num, temp, \
 21                 (temp & RH_PS_PRSC) ? " PRSC" : "", \
 22                 (temp & RH_PS_OCIC) ? " OCIC" : "", \
 23                 (temp & RH_PS_PSSC) ? " PSSC" : "", \
 24                 (temp & RH_PS_PESC) ? " PESC" : "", \
 25                 (temp & RH_PS_CSC) ? " CSC" : "", \
 26                 \
 27                 (temp & RH_PS_LSDA) ? " LSDA" : "", \
 28                 (temp & RH_PS_PPS) ? " PPS" : "", \
 29                 (temp & RH_PS_PRS) ? " PRS" : "", \
 30                 (temp & RH_PS_POCI) ? " POCI" : "", \
 31                 (temp & RH_PS_PSS) ? " PSS" : "", \
 32                 \
 33                 (temp & RH_PS_PES) ? " PES" : "", \
 34                 (temp & RH_PS_CCS) ? " CCS" : "" \
 35                 );
 36 
 37 /*-------------------------------------------------------------------------*/
 38 
 39 /* hcd->hub_irq_enable() */
 40 static void ohci_rhsc_enable (struct usb_hcd *hcd)
 41 {
 42         struct ohci_hcd         *ohci = hcd_to_ohci (hcd);
 43 
 44         spin_lock_irq(&ohci->lock);
 45         if (!ohci->autostop)
 46                 del_timer(&hcd->rh_timer);      /* Prevent next poll */
 47         ohci_writel(ohci, OHCI_INTR_RHSC, &ohci->regs->intrenable);
 48         spin_unlock_irq(&ohci->lock);
 49 }
 50 
 51 #define OHCI_SCHED_ENABLES \
 52         (OHCI_CTRL_CLE|OHCI_CTRL_BLE|OHCI_CTRL_PLE|OHCI_CTRL_IE)
 53 
 54 static void dl_done_list (struct ohci_hcd *);
 55 static void finish_unlinks (struct ohci_hcd *, u16);
 56 
 57 #ifdef  CONFIG_PM
 58 static int ohci_rh_suspend (struct ohci_hcd *ohci, int autostop)
 59 __releases(ohci->lock)
 60 __acquires(ohci->lock)
 61 {
 62         int                     status = 0;
 63 
 64         ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
 65         switch (ohci->hc_control & OHCI_CTRL_HCFS) {
 66         case OHCI_USB_RESUME:
 67                 ohci_dbg (ohci, "resume/suspend?\n");
 68                 ohci->hc_control &= ~OHCI_CTRL_HCFS;
 69                 ohci->hc_control |= OHCI_USB_RESET;
 70                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
 71                 (void) ohci_readl (ohci, &ohci->regs->control);
 72                 /* FALL THROUGH */
 73         case OHCI_USB_RESET:
 74                 status = -EBUSY;
 75                 ohci_dbg (ohci, "needs reinit!\n");
 76                 goto done;
 77         case OHCI_USB_SUSPEND:
 78                 if (!ohci->autostop) {
 79                         ohci_dbg (ohci, "already suspended\n");
 80                         goto done;
 81                 }
 82         }
 83         ohci_dbg (ohci, "%s root hub\n",
 84                         autostop ? "auto-stop" : "suspend");
 85 
 86         /* First stop any processing */
 87         if (!autostop && (ohci->hc_control & OHCI_SCHED_ENABLES)) {
 88                 ohci->hc_control &= ~OHCI_SCHED_ENABLES;
 89                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
 90                 ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
 91                 ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrstatus);
 92 
 93                 /* sched disables take effect on the next frame,
 94                  * then the last WDH could take 6+ msec
 95                  */
 96                 ohci_dbg (ohci, "stopping schedules ...\n");
 97                 ohci->autostop = 0;
 98                 spin_unlock_irq (&ohci->lock);
 99                 msleep (8);
100                 spin_lock_irq (&ohci->lock);
101         }
102         dl_done_list (ohci);
103         finish_unlinks (ohci, ohci_frame_no(ohci));
104 
105         /* maybe resume can wake root hub */
106         if (device_may_wakeup(&ohci_to_hcd(ohci)->self.root_hub->dev) ||
107                         autostop)
108                 ohci->hc_control |= OHCI_CTRL_RWE;
109         else {
110                 ohci_writel (ohci, OHCI_INTR_RHSC, &ohci->regs->intrdisable);
111                 ohci->hc_control &= ~OHCI_CTRL_RWE;
112         }
113 
114         /* Suspend hub ... this is the "global (to this bus) suspend" mode,
115          * which doesn't imply ports will first be individually suspended.
116          */
117         ohci->hc_control &= ~OHCI_CTRL_HCFS;
118         ohci->hc_control |= OHCI_USB_SUSPEND;
119         ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
120         (void) ohci_readl (ohci, &ohci->regs->control);
121 
122         /* no resumes until devices finish suspending */
123         if (!autostop) {
124                 ohci->next_statechange = jiffies + msecs_to_jiffies (5);
125                 ohci->autostop = 0;
126         }
127 
128 done:
129         return status;
130 }
131 
132 static inline struct ed *find_head (struct ed *ed)
133 {
134         /* for bulk and control lists */
135         while (ed->ed_prev)
136                 ed = ed->ed_prev;
137         return ed;
138 }
139 
140 /* caller has locked the root hub */
141 static int ohci_rh_resume (struct ohci_hcd *ohci)
142 __releases(ohci->lock)
143 __acquires(ohci->lock)
144 {
145         struct usb_hcd          *hcd = ohci_to_hcd (ohci);
146         u32                     temp, enables;
147         int                     status = -EINPROGRESS;
148         int                     autostopped = ohci->autostop;
149 
150         ohci->autostop = 0;
151         ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
152 
153         if (ohci->hc_control & (OHCI_CTRL_IR | OHCI_SCHED_ENABLES)) {
154                 /* this can happen after resuming a swsusp snapshot */
155                 if (hcd->state == HC_STATE_RESUMING) {
156                         ohci_dbg (ohci, "BIOS/SMM active, control %03x\n",
157                                         ohci->hc_control);
158                         status = -EBUSY;
159                 /* this happens when pmcore resumes HC then root */
160                 } else {
161                         ohci_dbg (ohci, "duplicate resume\n");
162                         status = 0;
163                 }
164         } else switch (ohci->hc_control & OHCI_CTRL_HCFS) {
165         case OHCI_USB_SUSPEND:
166                 ohci->hc_control &= ~(OHCI_CTRL_HCFS|OHCI_SCHED_ENABLES);
167                 ohci->hc_control |= OHCI_USB_RESUME;
168                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
169                 (void) ohci_readl (ohci, &ohci->regs->control);
170                 ohci_dbg (ohci, "%s root hub\n",
171                                 autostopped ? "auto-start" : "resume");
172                 break;
173         case OHCI_USB_RESUME:
174                 /* HCFS changes sometime after INTR_RD */
175                 ohci_dbg(ohci, "%swakeup root hub\n",
176                                 autostopped ? "auto-" : "");
177                 break;
178         case OHCI_USB_OPER:
179                 /* this can happen after resuming a swsusp snapshot */
180                 ohci_dbg (ohci, "snapshot resume? reinit\n");
181                 status = -EBUSY;
182                 break;
183         default:                /* RESET, we lost power */
184                 ohci_dbg (ohci, "lost power\n");
185                 status = -EBUSY;
186         }
187         if (status == -EBUSY) {
188                 if (!autostopped) {
189                         spin_unlock_irq (&ohci->lock);
190                         (void) ohci_init (ohci);
191                         status = ohci_restart (ohci);
192 
193                         usb_root_hub_lost_power(hcd->self.root_hub);
194 
195                         spin_lock_irq (&ohci->lock);
196                 }
197                 return status;
198         }
199         if (status != -EINPROGRESS)
200                 return status;
201         if (autostopped)
202                 goto skip_resume;
203         spin_unlock_irq (&ohci->lock);
204 
205         /* Some controllers (lucent erratum) need extra-long delays */
206         msleep (20 /* usb 11.5.1.10 */ + 12 /* 32 msec counter */ + 1);
207 
208         temp = ohci_readl (ohci, &ohci->regs->control);
209         temp &= OHCI_CTRL_HCFS;
210         if (temp != OHCI_USB_RESUME) {
211                 ohci_err (ohci, "controller won't resume\n");
212                 spin_lock_irq(&ohci->lock);
213                 return -EBUSY;
214         }
215 
216         /* disable old schedule state, reinit from scratch */
217         ohci_writel (ohci, 0, &ohci->regs->ed_controlhead);
218         ohci_writel (ohci, 0, &ohci->regs->ed_controlcurrent);
219         ohci_writel (ohci, 0, &ohci->regs->ed_bulkhead);
220         ohci_writel (ohci, 0, &ohci->regs->ed_bulkcurrent);
221         ohci_writel (ohci, 0, &ohci->regs->ed_periodcurrent);
222         ohci_writel (ohci, (u32) ohci->hcca_dma, &ohci->regs->hcca);
223 
224         /* Sometimes PCI D3 suspend trashes frame timings ... */
225         periodic_reinit (ohci);
226 
227         /* the following code is executed with ohci->lock held and
228          * irqs disabled if and only if autostopped is true
229          */
230 
231 skip_resume:
232         /* interrupts might have been disabled */
233         ohci_writel (ohci, OHCI_INTR_INIT, &ohci->regs->intrenable);
234         if (ohci->ed_rm_list)
235                 ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrenable);
236 
237         /* Then re-enable operations */
238         ohci_writel (ohci, OHCI_USB_OPER, &ohci->regs->control);
239         (void) ohci_readl (ohci, &ohci->regs->control);
240         if (!autostopped)
241                 msleep (3);
242 
243         temp = ohci->hc_control;
244         temp &= OHCI_CTRL_RWC;
245         temp |= OHCI_CONTROL_INIT | OHCI_USB_OPER;
246         ohci->hc_control = temp;
247         ohci_writel (ohci, temp, &ohci->regs->control);
248         (void) ohci_readl (ohci, &ohci->regs->control);
249 
250         /* TRSMRCY */
251         if (!autostopped) {
252                 msleep (10);
253                 spin_lock_irq (&ohci->lock);
254         }
255         /* now ohci->lock is always held and irqs are always disabled */
256 
257         /* keep it alive for more than ~5x suspend + resume costs */
258         ohci->next_statechange = jiffies + STATECHANGE_DELAY;
259 
260         /* maybe turn schedules back on */
261         enables = 0;
262         temp = 0;
263         if (!ohci->ed_rm_list) {
264                 if (ohci->ed_controltail) {
265                         ohci_writel (ohci,
266                                         find_head (ohci->ed_controltail)->dma,
267                                         &ohci->regs->ed_controlhead);
268                         enables |= OHCI_CTRL_CLE;
269                         temp |= OHCI_CLF;
270                 }
271                 if (ohci->ed_bulktail) {
272                         ohci_writel (ohci, find_head (ohci->ed_bulktail)->dma,
273                                 &ohci->regs->ed_bulkhead);
274                         enables |= OHCI_CTRL_BLE;
275                         temp |= OHCI_BLF;
276                 }
277         }
278         if (hcd->self.bandwidth_isoc_reqs || hcd->self.bandwidth_int_reqs)
279                 enables |= OHCI_CTRL_PLE|OHCI_CTRL_IE;
280         if (enables) {
281                 ohci_dbg (ohci, "restarting schedules ... %08x\n", enables);
282                 ohci->hc_control |= enables;
283                 ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
284                 if (temp)
285                         ohci_writel (ohci, temp, &ohci->regs->cmdstatus);
286                 (void) ohci_readl (ohci, &ohci->regs->control);
287         }
288 
289         return 0;
290 }
291 
292 static int ohci_bus_suspend (struct usb_hcd *hcd)
293 {
294         struct ohci_hcd         *ohci = hcd_to_ohci (hcd);
295         int                     rc;
296 
297         spin_lock_irq (&ohci->lock);
298 
299         if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
300                 rc = -ESHUTDOWN;
301         else
302                 rc = ohci_rh_suspend (ohci, 0);
303         spin_unlock_irq (&ohci->lock);
304         return rc;
305 }
306 
307 static int ohci_bus_resume (struct usb_hcd *hcd)
308 {
309         struct ohci_hcd         *ohci = hcd_to_ohci (hcd);
310         int                     rc;
311 
312         if (time_before (jiffies, ohci->next_statechange))
313                 msleep(5);
314 
315         spin_lock_irq (&ohci->lock);
316 
317         if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
318                 rc = -ESHUTDOWN;
319         else
320                 rc = ohci_rh_resume (ohci);
321         spin_unlock_irq (&ohci->lock);
322 
323         /* poll until we know a device is connected or we autostop */
324         if (rc == 0)
325                 usb_hcd_poll_rh_status(hcd);
326         return rc;
327 }
328 
329 /* Carry out the final steps of resuming the controller device */
330 static void ohci_finish_controller_resume(struct usb_hcd *hcd)
331 {
332         struct ohci_hcd         *ohci = hcd_to_ohci(hcd);
333         int                     port;
334         bool                    need_reinit = false;
335 
336         /* See if the controller is already running or has been reset */
337         ohci->hc_control = ohci_readl(ohci, &ohci->regs->control);
338         if (ohci->hc_control & (OHCI_CTRL_IR | OHCI_SCHED_ENABLES)) {
339                 need_reinit = true;
340         } else {
341                 switch (ohci->hc_control & OHCI_CTRL_HCFS) {
342                 case OHCI_USB_OPER:
343                 case OHCI_USB_RESET:
344                         need_reinit = true;
345                 }
346         }
347 
348         /* If needed, reinitialize and suspend the root hub */
349         if (need_reinit) {
350                 spin_lock_irq(&ohci->lock);
351                 hcd->state = HC_STATE_RESUMING;
352                 ohci_rh_resume(ohci);
353                 hcd->state = HC_STATE_QUIESCING;
354                 ohci_rh_suspend(ohci, 0);
355                 hcd->state = HC_STATE_SUSPENDED;
356                 spin_unlock_irq(&ohci->lock);
357         }
358 
359         /* Normally just turn on port power and enable interrupts */
360         else {
361                 ohci_dbg(ohci, "powerup ports\n");
362                 for (port = 0; port < ohci->num_ports; port++)
363                         ohci_writel(ohci, RH_PS_PPS,
364                                         &ohci->regs->roothub.portstatus[port]);
365 
366                 ohci_writel(ohci, OHCI_INTR_MIE, &ohci->regs->intrenable);
367                 ohci_readl(ohci, &ohci->regs->intrenable);
368                 msleep(20);
369         }
370 }
371 
372 /* Carry out polling-, autostop-, and autoresume-related state changes */
373 static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
374                 int any_connected)
375 {
376         int     poll_rh = 1;
377 
378         switch (ohci->hc_control & OHCI_CTRL_HCFS) {
379 
380         case OHCI_USB_OPER:
381                 /* keep on polling until we know a device is connected
382                  * and RHSC is enabled */
383                 if (!ohci->autostop) {
384                         if (any_connected ||
385                                         !device_may_wakeup(&ohci_to_hcd(ohci)
386                                                 ->self.root_hub->dev)) {
387                                 if (ohci_readl(ohci, &ohci->regs->intrenable) &
388                                                 OHCI_INTR_RHSC)
389                                         poll_rh = 0;
390                         } else {
391                                 ohci->autostop = 1;
392                                 ohci->next_statechange = jiffies + HZ;
393                         }
394 
395                 /* if no devices have been attached for one second, autostop */
396                 } else {
397                         if (changed || any_connected) {
398                                 ohci->autostop = 0;
399                                 ohci->next_statechange = jiffies +
400                                                 STATECHANGE_DELAY;
401                         } else if (time_after_eq(jiffies,
402                                                 ohci->next_statechange)
403                                         && !ohci->ed_rm_list
404                                         && !(ohci->hc_control &
405                                                 OHCI_SCHED_ENABLES)) {
406                                 ohci_rh_suspend(ohci, 1);
407                         }
408                 }
409                 break;
410 
411         /* if there is a port change, autostart or ask to be resumed */
412         case OHCI_USB_SUSPEND:
413         case OHCI_USB_RESUME:
414                 if (changed) {
415                         if (ohci->autostop)
416                                 ohci_rh_resume(ohci);
417                         else
418                                 usb_hcd_resume_root_hub(ohci_to_hcd(ohci));
419                 } else {
420                         /* everything is idle, no need for polling */
421                         poll_rh = 0;
422                 }
423                 break;
424         }
425         return poll_rh;
426 }
427 
428 #else   /* CONFIG_PM */
429 
430 static inline int ohci_rh_resume(struct ohci_hcd *ohci)
431 {
432         return 0;
433 }
434 
435 /* Carry out polling-related state changes.
436  * autostop isn't used when CONFIG_PM is turned off.
437  */
438 static int ohci_root_hub_state_changes(struct ohci_hcd *ohci, int changed,
439                 int any_connected)
440 {
441         int     poll_rh = 1;
442 
443         /* keep on polling until RHSC is enabled */
444         if (ohci_readl(ohci, &ohci->regs->intrenable) & OHCI_INTR_RHSC)
445                 poll_rh = 0;
446         return poll_rh;
447 }
448 
449 #endif  /* CONFIG_PM */
450 
451 /*-------------------------------------------------------------------------*/
452 
453 /* build "status change" packet (one or two bytes) from HC registers */
454 
455 static int
456 ohci_hub_status_data (struct usb_hcd *hcd, char *buf)
457 {
458         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
459         int             i, changed = 0, length = 1;
460         int             any_connected = 0;
461         unsigned long   flags;
462 
463         spin_lock_irqsave (&ohci->lock, flags);
464         if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags))
465                 goto done;
466 
467         /* undocumented erratum seen on at least rev D */
468         if ((ohci->flags & OHCI_QUIRK_AMD756)
469                         && (roothub_a (ohci) & RH_A_NDP) > MAX_ROOT_PORTS) {
470                 ohci_warn (ohci, "bogus NDP, rereads as NDP=%d\n",
471                           ohci_readl (ohci, &ohci->regs->roothub.a) & RH_A_NDP);
472                 /* retry later; "should not happen" */
473                 goto done;
474         }
475 
476         /* init status */
477         if (roothub_status (ohci) & (RH_HS_LPSC | RH_HS_OCIC))
478                 buf [0] = changed = 1;
479         else
480                 buf [0] = 0;
481         if (ohci->num_ports > 7) {
482                 buf [1] = 0;
483                 length++;
484         }
485 
486         /* look at each port */
487         for (i = 0; i < ohci->num_ports; i++) {
488                 u32     status = roothub_portstatus (ohci, i);
489 
490                 /* can't autostop if ports are connected */
491                 any_connected |= (status & RH_PS_CCS);
492 
493                 if (status & (RH_PS_CSC | RH_PS_PESC | RH_PS_PSSC
494                                 | RH_PS_OCIC | RH_PS_PRSC)) {
495                         changed = 1;
496                         if (i < 7)
497                             buf [0] |= 1 << (i + 1);
498                         else
499                             buf [1] |= 1 << (i - 7);
500                 }
501         }
502 
503         hcd->poll_rh = ohci_root_hub_state_changes(ohci, changed,
504                         any_connected);
505 
506 done:
507         spin_unlock_irqrestore (&ohci->lock, flags);
508 
509         return changed ? length : 0;
510 }
511 
512 /*-------------------------------------------------------------------------*/
513 
514 static void
515 ohci_hub_descriptor (
516         struct ohci_hcd                 *ohci,
517         struct usb_hub_descriptor       *desc
518 ) {
519         u32             rh = roothub_a (ohci);
520         u16             temp;
521 
522         desc->bDescriptorType = 0x29;
523         desc->bPwrOn2PwrGood = (rh & RH_A_POTPGT) >> 24;
524         desc->bHubContrCurrent = 0;
525 
526         desc->bNbrPorts = ohci->num_ports;
527         temp = 1 + (ohci->num_ports / 8);
528         desc->bDescLength = 7 + 2 * temp;
529 
530         temp = 0;
531         if (rh & RH_A_NPS)              /* no power switching? */
532             temp |= 0x0002;
533         if (rh & RH_A_PSM)              /* per-port power switching? */
534             temp |= 0x0001;
535         if (rh & RH_A_NOCP)             /* no overcurrent reporting? */
536             temp |= 0x0010;
537         else if (rh & RH_A_OCPM)        /* per-port overcurrent reporting? */
538             temp |= 0x0008;
539         desc->wHubCharacteristics = (__force __u16)cpu_to_hc16(ohci, temp);
540 
541         /* two bitmaps:  ports removable, and usb 1.0 legacy PortPwrCtrlMask */
542         rh = roothub_b (ohci);
543         memset(desc->bitmap, 0xff, sizeof(desc->bitmap));
544         desc->bitmap [0] = rh & RH_B_DR;
545         if (ohci->num_ports > 7) {
546                 desc->bitmap [1] = (rh & RH_B_DR) >> 8;
547                 desc->bitmap [2] = 0xff;
548         } else
549                 desc->bitmap [1] = 0xff;
550 }
551 
552 /*-------------------------------------------------------------------------*/
553 
554 #ifdef  CONFIG_USB_OTG
555 
556 static int ohci_start_port_reset (struct usb_hcd *hcd, unsigned port)
557 {
558         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
559         u32                     status;
560 
561         if (!port)
562                 return -EINVAL;
563         port--;
564 
565         /* start port reset before HNP protocol times out */
566         status = ohci_readl(ohci, &ohci->regs->roothub.portstatus [port]);
567         if (!(status & RH_PS_CCS))
568                 return -ENODEV;
569 
570         /* khubd will finish the reset later */
571         ohci_writel(ohci, RH_PS_PRS, &ohci->regs->roothub.portstatus [port]);
572         return 0;
573 }
574 
575 static void start_hnp(struct ohci_hcd *ohci);
576 
577 #else
578 
579 #define ohci_start_port_reset           NULL
580 
581 #endif
582 
583 /*-------------------------------------------------------------------------*/
584 
585 
586 /* See usb 7.1.7.5:  root hubs must issue at least 50 msec reset signaling,
587  * not necessarily continuous ... to guard against resume signaling.
588  * The short timeout is safe for non-root hubs, and is backward-compatible
589  * with earlier Linux hosts.
590  */
591 #ifdef  CONFIG_USB_SUSPEND
592 #define PORT_RESET_MSEC         50
593 #else
594 #define PORT_RESET_MSEC         10
595 #endif
596 
597 /* this timer value might be vendor-specific ... */
598 #define PORT_RESET_HW_MSEC      10
599 
600 /* wrap-aware logic morphed from <linux/jiffies.h> */
601 #define tick_before(t1,t2) ((s16)(((s16)(t1))-((s16)(t2))) < 0)
602 
603 /* called from some task, normally khubd */
604 static inline int root_port_reset (struct ohci_hcd *ohci, unsigned port)
605 {
606         __hc32 __iomem *portstat = &ohci->regs->roothub.portstatus [port];
607         u32     temp;
608         u16     now = ohci_readl(ohci, &ohci->regs->fmnumber);
609         u16     reset_done = now + PORT_RESET_MSEC;
610 
611         /* build a "continuous enough" reset signal, with up to
612          * 3msec gap between pulses.  scheduler HZ==100 must work;
613          * this might need to be deadline-scheduled.
614          */
615         do {
616                 /* spin until any current reset finishes */
617                 for (;;) {
618                         temp = ohci_readl (ohci, portstat);
619                         /* handle e.g. CardBus eject */
620                         if (temp == ~(u32)0)
621                                 return -ESHUTDOWN;
622                         if (!(temp & RH_PS_PRS))
623                                 break;
624                         udelay (500);
625                 }
626 
627                 if (!(temp & RH_PS_CCS))
628                         break;
629                 if (temp & RH_PS_PRSC)
630                         ohci_writel (ohci, RH_PS_PRSC, portstat);
631 
632                 /* start the next reset, sleep till it's probably done */
633                 ohci_writel (ohci, RH_PS_PRS, portstat);
634                 msleep(PORT_RESET_HW_MSEC);
635                 now = ohci_readl(ohci, &ohci->regs->fmnumber);
636         } while (tick_before(now, reset_done));
637         /* caller synchronizes using PRSC */
638 
639         return 0;
640 }
641 
642 static int ohci_hub_control (
643         struct usb_hcd  *hcd,
644         u16             typeReq,
645         u16             wValue,
646         u16             wIndex,
647         char            *buf,
648         u16             wLength
649 ) {
650         struct ohci_hcd *ohci = hcd_to_ohci (hcd);
651         int             ports = hcd_to_bus (hcd)->root_hub->maxchild;
652         u32             temp;
653         int             retval = 0;
654 
655         if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
656                 return -ESHUTDOWN;
657 
658         switch (typeReq) {
659         case ClearHubFeature:
660                 switch (wValue) {
661                 case C_HUB_OVER_CURRENT:
662                         ohci_writel (ohci, RH_HS_OCIC,
663                                         &ohci->regs->roothub.status);
664                 case C_HUB_LOCAL_POWER:
665                         break;
666                 default:
667                         goto error;
668                 }
669                 break;
670         case ClearPortFeature:
671                 if (!wIndex || wIndex > ports)
672                         goto error;
673                 wIndex--;
674 
675                 switch (wValue) {
676                 case USB_PORT_FEAT_ENABLE:
677                         temp = RH_PS_CCS;
678                         break;
679                 case USB_PORT_FEAT_C_ENABLE:
680                         temp = RH_PS_PESC;
681                         break;
682                 case USB_PORT_FEAT_SUSPEND:
683                         temp = RH_PS_POCI;
684                         break;
685                 case USB_PORT_FEAT_C_SUSPEND:
686                         temp = RH_PS_PSSC;
687                         break;
688                 case USB_PORT_FEAT_POWER:
689                         temp = RH_PS_LSDA;
690                         break;
691                 case USB_PORT_FEAT_C_CONNECTION:
692                         temp = RH_PS_CSC;
693                         break;
694                 case USB_PORT_FEAT_C_OVER_CURRENT:
695                         temp = RH_PS_OCIC;
696                         break;
697                 case USB_PORT_FEAT_C_RESET:
698                         temp = RH_PS_PRSC;
699                         break;
700                 default:
701                         goto error;
702                 }
703                 ohci_writel (ohci, temp,
704                                 &ohci->regs->roothub.portstatus [wIndex]);
705                 // ohci_readl (ohci, &ohci->regs->roothub.portstatus [wIndex]);
706                 break;
707         case GetHubDescriptor:
708                 ohci_hub_descriptor (ohci, (struct usb_hub_descriptor *) buf);
709                 break;
710         case GetHubStatus:
711                 temp = roothub_status (ohci) & ~(RH_HS_CRWE | RH_HS_DRWE);
712                 put_unaligned(cpu_to_le32 (temp), (__le32 *) buf);
713                 break;
714         case GetPortStatus:
715                 if (!wIndex || wIndex > ports)
716                         goto error;
717                 wIndex--;
718                 temp = roothub_portstatus (ohci, wIndex);
719                 put_unaligned(cpu_to_le32 (temp), (__le32 *) buf);
720 
721 #ifndef OHCI_VERBOSE_DEBUG
722         if (*(u16*)(buf+2))     /* only if wPortChange is interesting */
723 #endif
724                 dbg_port (ohci, "GetStatus", wIndex, temp);
725                 break;
726         case SetHubFeature:
727                 switch (wValue) {
728                 case C_HUB_OVER_CURRENT:
729                         // FIXME:  this can be cleared, yes?
730                 case C_HUB_LOCAL_POWER:
731                         break;
732                 default:
733                         goto error;
734                 }
735                 break;
736         case SetPortFeature:
737                 if (!wIndex || wIndex > ports)
738                         goto error;
739                 wIndex--;
740                 switch (wValue) {
741                 case USB_PORT_FEAT_SUSPEND:
742 #ifdef  CONFIG_USB_OTG
743                         if (hcd->self.otg_port == (wIndex + 1)
744                                         && hcd->self.b_hnp_enable)
745                                 start_hnp(ohci);
746                         else
747 #endif
748                         ohci_writel (ohci, RH_PS_PSS,
749                                 &ohci->regs->roothub.portstatus [wIndex]);
750                         break;
751                 case USB_PORT_FEAT_POWER:
752                         ohci_writel (ohci, RH_PS_PPS,
753                                 &ohci->regs->roothub.portstatus [wIndex]);
754                         break;
755                 case USB_PORT_FEAT_RESET:
756                         retval = root_port_reset (ohci, wIndex);
757                         break;
758                 default:
759                         goto error;
760                 }
761                 break;
762 
763         default:
764 error:
765                 /* "protocol stall" on error */
766                 retval = -EPIPE;
767         }
768         return retval;
769 }
770 
771 
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