Merge ARM fixes
[linux-2.6] / drivers / usb / host / uhci-q.c
1 /*
2  * Universal Host Controller Interface driver for USB.
3  *
4  * Maintainer: Alan Stern <stern@rowland.harvard.edu>
5  *
6  * (C) Copyright 1999 Linus Torvalds
7  * (C) Copyright 1999-2002 Johannes Erdfelt, johannes@erdfelt.com
8  * (C) Copyright 1999 Randy Dunlap
9  * (C) Copyright 1999 Georg Acher, acher@in.tum.de
10  * (C) Copyright 1999 Deti Fliegl, deti@fliegl.de
11  * (C) Copyright 1999 Thomas Sailer, sailer@ife.ee.ethz.ch
12  * (C) Copyright 1999 Roman Weissgaerber, weissg@vienna.at
13  * (C) Copyright 2000 Yggdrasil Computing, Inc. (port of new PCI interface
14  *               support from usb-ohci.c by Adam Richter, adam@yggdrasil.com).
15  * (C) Copyright 1999 Gregory P. Smith (from usb-ohci.c)
16  * (C) Copyright 2004-2006 Alan Stern, stern@rowland.harvard.edu
17  */
18
19
20 /*
21  * Technically, updating td->status here is a race, but it's not really a
22  * problem. The worst that can happen is that we set the IOC bit again
23  * generating a spurious interrupt. We could fix this by creating another
24  * QH and leaving the IOC bit always set, but then we would have to play
25  * games with the FSBR code to make sure we get the correct order in all
26  * the cases. I don't think it's worth the effort
27  */
28 static void uhci_set_next_interrupt(struct uhci_hcd *uhci)
29 {
30         if (uhci->is_stopped)
31                 mod_timer(&uhci_to_hcd(uhci)->rh_timer, jiffies);
32         uhci->term_td->status |= cpu_to_le32(TD_CTRL_IOC); 
33 }
34
35 static inline void uhci_clear_next_interrupt(struct uhci_hcd *uhci)
36 {
37         uhci->term_td->status &= ~cpu_to_le32(TD_CTRL_IOC);
38 }
39
40
41 /*
42  * Full-Speed Bandwidth Reclamation (FSBR).
43  * We turn on FSBR whenever a queue that wants it is advancing,
44  * and leave it on for a short time thereafter.
45  */
46 static void uhci_fsbr_on(struct uhci_hcd *uhci)
47 {
48         uhci->fsbr_is_on = 1;
49         uhci->skel_term_qh->link = cpu_to_le32(
50                         uhci->skel_fs_control_qh->dma_handle) | UHCI_PTR_QH;
51 }
52
53 static void uhci_fsbr_off(struct uhci_hcd *uhci)
54 {
55         uhci->fsbr_is_on = 0;
56         uhci->skel_term_qh->link = UHCI_PTR_TERM;
57 }
58
59 static void uhci_add_fsbr(struct uhci_hcd *uhci, struct urb *urb)
60 {
61         struct urb_priv *urbp = urb->hcpriv;
62
63         if (!(urb->transfer_flags & URB_NO_FSBR))
64                 urbp->fsbr = 1;
65 }
66
67 static void uhci_urbp_wants_fsbr(struct uhci_hcd *uhci, struct urb_priv *urbp)
68 {
69         if (urbp->fsbr) {
70                 uhci->fsbr_is_wanted = 1;
71                 if (!uhci->fsbr_is_on)
72                         uhci_fsbr_on(uhci);
73                 else if (uhci->fsbr_expiring) {
74                         uhci->fsbr_expiring = 0;
75                         del_timer(&uhci->fsbr_timer);
76                 }
77         }
78 }
79
80 static void uhci_fsbr_timeout(unsigned long _uhci)
81 {
82         struct uhci_hcd *uhci = (struct uhci_hcd *) _uhci;
83         unsigned long flags;
84
85         spin_lock_irqsave(&uhci->lock, flags);
86         if (uhci->fsbr_expiring) {
87                 uhci->fsbr_expiring = 0;
88                 uhci_fsbr_off(uhci);
89         }
90         spin_unlock_irqrestore(&uhci->lock, flags);
91 }
92
93
94 static struct uhci_td *uhci_alloc_td(struct uhci_hcd *uhci)
95 {
96         dma_addr_t dma_handle;
97         struct uhci_td *td;
98
99         td = dma_pool_alloc(uhci->td_pool, GFP_ATOMIC, &dma_handle);
100         if (!td)
101                 return NULL;
102
103         td->dma_handle = dma_handle;
104         td->frame = -1;
105
106         INIT_LIST_HEAD(&td->list);
107         INIT_LIST_HEAD(&td->fl_list);
108
109         return td;
110 }
111
112 static void uhci_free_td(struct uhci_hcd *uhci, struct uhci_td *td)
113 {
114         if (!list_empty(&td->list))
115                 dev_warn(uhci_dev(uhci), "td %p still in list!\n", td);
116         if (!list_empty(&td->fl_list))
117                 dev_warn(uhci_dev(uhci), "td %p still in fl_list!\n", td);
118
119         dma_pool_free(uhci->td_pool, td, td->dma_handle);
120 }
121
122 static inline void uhci_fill_td(struct uhci_td *td, u32 status,
123                 u32 token, u32 buffer)
124 {
125         td->status = cpu_to_le32(status);
126         td->token = cpu_to_le32(token);
127         td->buffer = cpu_to_le32(buffer);
128 }
129
130 static void uhci_add_td_to_urbp(struct uhci_td *td, struct urb_priv *urbp)
131 {
132         list_add_tail(&td->list, &urbp->td_list);
133 }
134
135 static void uhci_remove_td_from_urbp(struct uhci_td *td)
136 {
137         list_del_init(&td->list);
138 }
139
140 /*
141  * We insert Isochronous URBs directly into the frame list at the beginning
142  */
143 static inline void uhci_insert_td_in_frame_list(struct uhci_hcd *uhci,
144                 struct uhci_td *td, unsigned framenum)
145 {
146         framenum &= (UHCI_NUMFRAMES - 1);
147
148         td->frame = framenum;
149
150         /* Is there a TD already mapped there? */
151         if (uhci->frame_cpu[framenum]) {
152                 struct uhci_td *ftd, *ltd;
153
154                 ftd = uhci->frame_cpu[framenum];
155                 ltd = list_entry(ftd->fl_list.prev, struct uhci_td, fl_list);
156
157                 list_add_tail(&td->fl_list, &ftd->fl_list);
158
159                 td->link = ltd->link;
160                 wmb();
161                 ltd->link = cpu_to_le32(td->dma_handle);
162         } else {
163                 td->link = uhci->frame[framenum];
164                 wmb();
165                 uhci->frame[framenum] = cpu_to_le32(td->dma_handle);
166                 uhci->frame_cpu[framenum] = td;
167         }
168 }
169
170 static inline void uhci_remove_td_from_frame_list(struct uhci_hcd *uhci,
171                 struct uhci_td *td)
172 {
173         /* If it's not inserted, don't remove it */
174         if (td->frame == -1) {
175                 WARN_ON(!list_empty(&td->fl_list));
176                 return;
177         }
178
179         if (uhci->frame_cpu[td->frame] == td) {
180                 if (list_empty(&td->fl_list)) {
181                         uhci->frame[td->frame] = td->link;
182                         uhci->frame_cpu[td->frame] = NULL;
183                 } else {
184                         struct uhci_td *ntd;
185
186                         ntd = list_entry(td->fl_list.next, struct uhci_td, fl_list);
187                         uhci->frame[td->frame] = cpu_to_le32(ntd->dma_handle);
188                         uhci->frame_cpu[td->frame] = ntd;
189                 }
190         } else {
191                 struct uhci_td *ptd;
192
193                 ptd = list_entry(td->fl_list.prev, struct uhci_td, fl_list);
194                 ptd->link = td->link;
195         }
196
197         list_del_init(&td->fl_list);
198         td->frame = -1;
199 }
200
201 static inline void uhci_remove_tds_from_frame(struct uhci_hcd *uhci,
202                 unsigned int framenum)
203 {
204         struct uhci_td *ftd, *ltd;
205
206         framenum &= (UHCI_NUMFRAMES - 1);
207
208         ftd = uhci->frame_cpu[framenum];
209         if (ftd) {
210                 ltd = list_entry(ftd->fl_list.prev, struct uhci_td, fl_list);
211                 uhci->frame[framenum] = ltd->link;
212                 uhci->frame_cpu[framenum] = NULL;
213
214                 while (!list_empty(&ftd->fl_list))
215                         list_del_init(ftd->fl_list.prev);
216         }
217 }
218
219 /*
220  * Remove all the TDs for an Isochronous URB from the frame list
221  */
222 static void uhci_unlink_isochronous_tds(struct uhci_hcd *uhci, struct urb *urb)
223 {
224         struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;
225         struct uhci_td *td;
226
227         list_for_each_entry(td, &urbp->td_list, list)
228                 uhci_remove_td_from_frame_list(uhci, td);
229 }
230
231 static struct uhci_qh *uhci_alloc_qh(struct uhci_hcd *uhci,
232                 struct usb_device *udev, struct usb_host_endpoint *hep)
233 {
234         dma_addr_t dma_handle;
235         struct uhci_qh *qh;
236
237         qh = dma_pool_alloc(uhci->qh_pool, GFP_ATOMIC, &dma_handle);
238         if (!qh)
239                 return NULL;
240
241         memset(qh, 0, sizeof(*qh));
242         qh->dma_handle = dma_handle;
243
244         qh->element = UHCI_PTR_TERM;
245         qh->link = UHCI_PTR_TERM;
246
247         INIT_LIST_HEAD(&qh->queue);
248         INIT_LIST_HEAD(&qh->node);
249
250         if (udev) {             /* Normal QH */
251                 qh->type = hep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
252                 if (qh->type != USB_ENDPOINT_XFER_ISOC) {
253                         qh->dummy_td = uhci_alloc_td(uhci);
254                         if (!qh->dummy_td) {
255                                 dma_pool_free(uhci->qh_pool, qh, dma_handle);
256                                 return NULL;
257                         }
258                 }
259                 qh->state = QH_STATE_IDLE;
260                 qh->hep = hep;
261                 qh->udev = udev;
262                 hep->hcpriv = qh;
263
264                 if (qh->type == USB_ENDPOINT_XFER_INT ||
265                                 qh->type == USB_ENDPOINT_XFER_ISOC)
266                         qh->load = usb_calc_bus_time(udev->speed,
267                                         usb_endpoint_dir_in(&hep->desc),
268                                         qh->type == USB_ENDPOINT_XFER_ISOC,
269                                         le16_to_cpu(hep->desc.wMaxPacketSize))
270                                 / 1000 + 1;
271
272         } else {                /* Skeleton QH */
273                 qh->state = QH_STATE_ACTIVE;
274                 qh->type = -1;
275         }
276         return qh;
277 }
278
279 static void uhci_free_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
280 {
281         WARN_ON(qh->state != QH_STATE_IDLE && qh->udev);
282         if (!list_empty(&qh->queue))
283                 dev_warn(uhci_dev(uhci), "qh %p list not empty!\n", qh);
284
285         list_del(&qh->node);
286         if (qh->udev) {
287                 qh->hep->hcpriv = NULL;
288                 if (qh->dummy_td)
289                         uhci_free_td(uhci, qh->dummy_td);
290         }
291         dma_pool_free(uhci->qh_pool, qh, qh->dma_handle);
292 }
293
294 /*
295  * When a queue is stopped and a dequeued URB is given back, adjust
296  * the previous TD link (if the URB isn't first on the queue) or
297  * save its toggle value (if it is first and is currently executing).
298  *
299  * Returns 0 if the URB should not yet be given back, 1 otherwise.
300  */
301 static int uhci_cleanup_queue(struct uhci_hcd *uhci, struct uhci_qh *qh,
302                 struct urb *urb)
303 {
304         struct urb_priv *urbp = urb->hcpriv;
305         struct uhci_td *td;
306         int ret = 1;
307
308         /* Isochronous pipes don't use toggles and their TD link pointers
309          * get adjusted during uhci_urb_dequeue().  But since their queues
310          * cannot truly be stopped, we have to watch out for dequeues
311          * occurring after the nominal unlink frame. */
312         if (qh->type == USB_ENDPOINT_XFER_ISOC) {
313                 ret = (uhci->frame_number + uhci->is_stopped !=
314                                 qh->unlink_frame);
315                 goto done;
316         }
317
318         /* If the URB isn't first on its queue, adjust the link pointer
319          * of the last TD in the previous URB.  The toggle doesn't need
320          * to be saved since this URB can't be executing yet. */
321         if (qh->queue.next != &urbp->node) {
322                 struct urb_priv *purbp;
323                 struct uhci_td *ptd;
324
325                 purbp = list_entry(urbp->node.prev, struct urb_priv, node);
326                 WARN_ON(list_empty(&purbp->td_list));
327                 ptd = list_entry(purbp->td_list.prev, struct uhci_td,
328                                 list);
329                 td = list_entry(urbp->td_list.prev, struct uhci_td,
330                                 list);
331                 ptd->link = td->link;
332                 goto done;
333         }
334
335         /* If the QH element pointer is UHCI_PTR_TERM then then currently
336          * executing URB has already been unlinked, so this one isn't it. */
337         if (qh_element(qh) == UHCI_PTR_TERM)
338                 goto done;
339         qh->element = UHCI_PTR_TERM;
340
341         /* Control pipes don't have to worry about toggles */
342         if (qh->type == USB_ENDPOINT_XFER_CONTROL)
343                 goto done;
344
345         /* Save the next toggle value */
346         WARN_ON(list_empty(&urbp->td_list));
347         td = list_entry(urbp->td_list.next, struct uhci_td, list);
348         qh->needs_fixup = 1;
349         qh->initial_toggle = uhci_toggle(td_token(td));
350
351 done:
352         return ret;
353 }
354
355 /*
356  * Fix up the data toggles for URBs in a queue, when one of them
357  * terminates early (short transfer, error, or dequeued).
358  */
359 static void uhci_fixup_toggles(struct uhci_qh *qh, int skip_first)
360 {
361         struct urb_priv *urbp = NULL;
362         struct uhci_td *td;
363         unsigned int toggle = qh->initial_toggle;
364         unsigned int pipe;
365
366         /* Fixups for a short transfer start with the second URB in the
367          * queue (the short URB is the first). */
368         if (skip_first)
369                 urbp = list_entry(qh->queue.next, struct urb_priv, node);
370
371         /* When starting with the first URB, if the QH element pointer is
372          * still valid then we know the URB's toggles are okay. */
373         else if (qh_element(qh) != UHCI_PTR_TERM)
374                 toggle = 2;
375
376         /* Fix up the toggle for the URBs in the queue.  Normally this
377          * loop won't run more than once: When an error or short transfer
378          * occurs, the queue usually gets emptied. */
379         urbp = list_prepare_entry(urbp, &qh->queue, node);
380         list_for_each_entry_continue(urbp, &qh->queue, node) {
381
382                 /* If the first TD has the right toggle value, we don't
383                  * need to change any toggles in this URB */
384                 td = list_entry(urbp->td_list.next, struct uhci_td, list);
385                 if (toggle > 1 || uhci_toggle(td_token(td)) == toggle) {
386                         td = list_entry(urbp->td_list.prev, struct uhci_td,
387                                         list);
388                         toggle = uhci_toggle(td_token(td)) ^ 1;
389
390                 /* Otherwise all the toggles in the URB have to be switched */
391                 } else {
392                         list_for_each_entry(td, &urbp->td_list, list) {
393                                 td->token ^= __constant_cpu_to_le32(
394                                                         TD_TOKEN_TOGGLE);
395                                 toggle ^= 1;
396                         }
397                 }
398         }
399
400         wmb();
401         pipe = list_entry(qh->queue.next, struct urb_priv, node)->urb->pipe;
402         usb_settoggle(qh->udev, usb_pipeendpoint(pipe),
403                         usb_pipeout(pipe), toggle);
404         qh->needs_fixup = 0;
405 }
406
407 /*
408  * Put a QH on the schedule in both hardware and software
409  */
410 static void uhci_activate_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
411 {
412         struct uhci_qh *pqh;
413
414         WARN_ON(list_empty(&qh->queue));
415
416         /* Set the element pointer if it isn't set already.
417          * This isn't needed for Isochronous queues, but it doesn't hurt. */
418         if (qh_element(qh) == UHCI_PTR_TERM) {
419                 struct urb_priv *urbp = list_entry(qh->queue.next,
420                                 struct urb_priv, node);
421                 struct uhci_td *td = list_entry(urbp->td_list.next,
422                                 struct uhci_td, list);
423
424                 qh->element = cpu_to_le32(td->dma_handle);
425         }
426
427         /* Treat the queue as if it has just advanced */
428         qh->wait_expired = 0;
429         qh->advance_jiffies = jiffies;
430
431         if (qh->state == QH_STATE_ACTIVE)
432                 return;
433         qh->state = QH_STATE_ACTIVE;
434
435         /* Move the QH from its old list to the end of the appropriate
436          * skeleton's list */
437         if (qh == uhci->next_qh)
438                 uhci->next_qh = list_entry(qh->node.next, struct uhci_qh,
439                                 node);
440         list_move_tail(&qh->node, &qh->skel->node);
441
442         /* Link it into the schedule */
443         pqh = list_entry(qh->node.prev, struct uhci_qh, node);
444         qh->link = pqh->link;
445         wmb();
446         pqh->link = UHCI_PTR_QH | cpu_to_le32(qh->dma_handle);
447 }
448
449 /*
450  * Take a QH off the hardware schedule
451  */
452 static void uhci_unlink_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
453 {
454         struct uhci_qh *pqh;
455
456         if (qh->state == QH_STATE_UNLINKING)
457                 return;
458         WARN_ON(qh->state != QH_STATE_ACTIVE || !qh->udev);
459         qh->state = QH_STATE_UNLINKING;
460
461         /* Unlink the QH from the schedule and record when we did it */
462         pqh = list_entry(qh->node.prev, struct uhci_qh, node);
463         pqh->link = qh->link;
464         mb();
465
466         uhci_get_current_frame_number(uhci);
467         qh->unlink_frame = uhci->frame_number;
468
469         /* Force an interrupt so we know when the QH is fully unlinked */
470         if (list_empty(&uhci->skel_unlink_qh->node))
471                 uhci_set_next_interrupt(uhci);
472
473         /* Move the QH from its old list to the end of the unlinking list */
474         if (qh == uhci->next_qh)
475                 uhci->next_qh = list_entry(qh->node.next, struct uhci_qh,
476                                 node);
477         list_move_tail(&qh->node, &uhci->skel_unlink_qh->node);
478 }
479
480 /*
481  * When we and the controller are through with a QH, it becomes IDLE.
482  * This happens when a QH has been off the schedule (on the unlinking
483  * list) for more than one frame, or when an error occurs while adding
484  * the first URB onto a new QH.
485  */
486 static void uhci_make_qh_idle(struct uhci_hcd *uhci, struct uhci_qh *qh)
487 {
488         WARN_ON(qh->state == QH_STATE_ACTIVE);
489
490         if (qh == uhci->next_qh)
491                 uhci->next_qh = list_entry(qh->node.next, struct uhci_qh,
492                                 node);
493         list_move(&qh->node, &uhci->idle_qh_list);
494         qh->state = QH_STATE_IDLE;
495
496         /* Now that the QH is idle, its post_td isn't being used */
497         if (qh->post_td) {
498                 uhci_free_td(uhci, qh->post_td);
499                 qh->post_td = NULL;
500         }
501
502         /* If anyone is waiting for a QH to become idle, wake them up */
503         if (uhci->num_waiting)
504                 wake_up_all(&uhci->waitqh);
505 }
506
507 /*
508  * Find the highest existing bandwidth load for a given phase and period.
509  */
510 static int uhci_highest_load(struct uhci_hcd *uhci, int phase, int period)
511 {
512         int highest_load = uhci->load[phase];
513
514         for (phase += period; phase < MAX_PHASE; phase += period)
515                 highest_load = max_t(int, highest_load, uhci->load[phase]);
516         return highest_load;
517 }
518
519 /*
520  * Set qh->phase to the optimal phase for a periodic transfer and
521  * check whether the bandwidth requirement is acceptable.
522  */
523 static int uhci_check_bandwidth(struct uhci_hcd *uhci, struct uhci_qh *qh)
524 {
525         int minimax_load;
526
527         /* Find the optimal phase (unless it is already set) and get
528          * its load value. */
529         if (qh->phase >= 0)
530                 minimax_load = uhci_highest_load(uhci, qh->phase, qh->period);
531         else {
532                 int phase, load;
533                 int max_phase = min_t(int, MAX_PHASE, qh->period);
534
535                 qh->phase = 0;
536                 minimax_load = uhci_highest_load(uhci, qh->phase, qh->period);
537                 for (phase = 1; phase < max_phase; ++phase) {
538                         load = uhci_highest_load(uhci, phase, qh->period);
539                         if (load < minimax_load) {
540                                 minimax_load = load;
541                                 qh->phase = phase;
542                         }
543                 }
544         }
545
546         /* Maximum allowable periodic bandwidth is 90%, or 900 us per frame */
547         if (minimax_load + qh->load > 900) {
548                 dev_dbg(uhci_dev(uhci), "bandwidth allocation failed: "
549                                 "period %d, phase %d, %d + %d us\n",
550                                 qh->period, qh->phase, minimax_load, qh->load);
551                 return -ENOSPC;
552         }
553         return 0;
554 }
555
556 /*
557  * Reserve a periodic QH's bandwidth in the schedule
558  */
559 static void uhci_reserve_bandwidth(struct uhci_hcd *uhci, struct uhci_qh *qh)
560 {
561         int i;
562         int load = qh->load;
563         char *p = "??";
564
565         for (i = qh->phase; i < MAX_PHASE; i += qh->period) {
566                 uhci->load[i] += load;
567                 uhci->total_load += load;
568         }
569         uhci_to_hcd(uhci)->self.bandwidth_allocated =
570                         uhci->total_load / MAX_PHASE;
571         switch (qh->type) {
572         case USB_ENDPOINT_XFER_INT:
573                 ++uhci_to_hcd(uhci)->self.bandwidth_int_reqs;
574                 p = "INT";
575                 break;
576         case USB_ENDPOINT_XFER_ISOC:
577                 ++uhci_to_hcd(uhci)->self.bandwidth_isoc_reqs;
578                 p = "ISO";
579                 break;
580         }
581         qh->bandwidth_reserved = 1;
582         dev_dbg(uhci_dev(uhci),
583                         "%s dev %d ep%02x-%s, period %d, phase %d, %d us\n",
584                         "reserve", qh->udev->devnum,
585                         qh->hep->desc.bEndpointAddress, p,
586                         qh->period, qh->phase, load);
587 }
588
589 /*
590  * Release a periodic QH's bandwidth reservation
591  */
592 static void uhci_release_bandwidth(struct uhci_hcd *uhci, struct uhci_qh *qh)
593 {
594         int i;
595         int load = qh->load;
596         char *p = "??";
597
598         for (i = qh->phase; i < MAX_PHASE; i += qh->period) {
599                 uhci->load[i] -= load;
600                 uhci->total_load -= load;
601         }
602         uhci_to_hcd(uhci)->self.bandwidth_allocated =
603                         uhci->total_load / MAX_PHASE;
604         switch (qh->type) {
605         case USB_ENDPOINT_XFER_INT:
606                 --uhci_to_hcd(uhci)->self.bandwidth_int_reqs;
607                 p = "INT";
608                 break;
609         case USB_ENDPOINT_XFER_ISOC:
610                 --uhci_to_hcd(uhci)->self.bandwidth_isoc_reqs;
611                 p = "ISO";
612                 break;
613         }
614         qh->bandwidth_reserved = 0;
615         dev_dbg(uhci_dev(uhci),
616                         "%s dev %d ep%02x-%s, period %d, phase %d, %d us\n",
617                         "release", qh->udev->devnum,
618                         qh->hep->desc.bEndpointAddress, p,
619                         qh->period, qh->phase, load);
620 }
621
622 static inline struct urb_priv *uhci_alloc_urb_priv(struct uhci_hcd *uhci,
623                 struct urb *urb)
624 {
625         struct urb_priv *urbp;
626
627         urbp = kmem_cache_zalloc(uhci_up_cachep, GFP_ATOMIC);
628         if (!urbp)
629                 return NULL;
630
631         urbp->urb = urb;
632         urb->hcpriv = urbp;
633         
634         INIT_LIST_HEAD(&urbp->node);
635         INIT_LIST_HEAD(&urbp->td_list);
636
637         return urbp;
638 }
639
640 static void uhci_free_urb_priv(struct uhci_hcd *uhci,
641                 struct urb_priv *urbp)
642 {
643         struct uhci_td *td, *tmp;
644
645         if (!list_empty(&urbp->node))
646                 dev_warn(uhci_dev(uhci), "urb %p still on QH's list!\n",
647                                 urbp->urb);
648
649         list_for_each_entry_safe(td, tmp, &urbp->td_list, list) {
650                 uhci_remove_td_from_urbp(td);
651                 uhci_free_td(uhci, td);
652         }
653
654         urbp->urb->hcpriv = NULL;
655         kmem_cache_free(uhci_up_cachep, urbp);
656 }
657
658 /*
659  * Map status to standard result codes
660  *
661  * <status> is (td_status(td) & 0xF60000), a.k.a.
662  * uhci_status_bits(td_status(td)).
663  * Note: <status> does not include the TD_CTRL_NAK bit.
664  * <dir_out> is True for output TDs and False for input TDs.
665  */
666 static int uhci_map_status(int status, int dir_out)
667 {
668         if (!status)
669                 return 0;
670         if (status & TD_CTRL_BITSTUFF)                  /* Bitstuff error */
671                 return -EPROTO;
672         if (status & TD_CTRL_CRCTIMEO) {                /* CRC/Timeout */
673                 if (dir_out)
674                         return -EPROTO;
675                 else
676                         return -EILSEQ;
677         }
678         if (status & TD_CTRL_BABBLE)                    /* Babble */
679                 return -EOVERFLOW;
680         if (status & TD_CTRL_DBUFERR)                   /* Buffer error */
681                 return -ENOSR;
682         if (status & TD_CTRL_STALLED)                   /* Stalled */
683                 return -EPIPE;
684         return 0;
685 }
686
687 /*
688  * Control transfers
689  */
690 static int uhci_submit_control(struct uhci_hcd *uhci, struct urb *urb,
691                 struct uhci_qh *qh)
692 {
693         struct uhci_td *td;
694         unsigned long destination, status;
695         int maxsze = le16_to_cpu(qh->hep->desc.wMaxPacketSize);
696         int len = urb->transfer_buffer_length;
697         dma_addr_t data = urb->transfer_dma;
698         __le32 *plink;
699         struct urb_priv *urbp = urb->hcpriv;
700
701         /* The "pipe" thing contains the destination in bits 8--18 */
702         destination = (urb->pipe & PIPE_DEVEP_MASK) | USB_PID_SETUP;
703
704         /* 3 errors, dummy TD remains inactive */
705         status = uhci_maxerr(3);
706         if (urb->dev->speed == USB_SPEED_LOW)
707                 status |= TD_CTRL_LS;
708
709         /*
710          * Build the TD for the control request setup packet
711          */
712         td = qh->dummy_td;
713         uhci_add_td_to_urbp(td, urbp);
714         uhci_fill_td(td, status, destination | uhci_explen(8),
715                         urb->setup_dma);
716         plink = &td->link;
717         status |= TD_CTRL_ACTIVE;
718
719         /*
720          * If direction is "send", change the packet ID from SETUP (0x2D)
721          * to OUT (0xE1).  Else change it from SETUP to IN (0x69) and
722          * set Short Packet Detect (SPD) for all data packets.
723          */
724         if (usb_pipeout(urb->pipe))
725                 destination ^= (USB_PID_SETUP ^ USB_PID_OUT);
726         else {
727                 destination ^= (USB_PID_SETUP ^ USB_PID_IN);
728                 status |= TD_CTRL_SPD;
729         }
730
731         /*
732          * Build the DATA TDs
733          */
734         while (len > 0) {
735                 int pktsze = min(len, maxsze);
736
737                 td = uhci_alloc_td(uhci);
738                 if (!td)
739                         goto nomem;
740                 *plink = cpu_to_le32(td->dma_handle);
741
742                 /* Alternate Data0/1 (start with Data1) */
743                 destination ^= TD_TOKEN_TOGGLE;
744         
745                 uhci_add_td_to_urbp(td, urbp);
746                 uhci_fill_td(td, status, destination | uhci_explen(pktsze),
747                                 data);
748                 plink = &td->link;
749
750                 data += pktsze;
751                 len -= pktsze;
752         }
753
754         /*
755          * Build the final TD for control status 
756          */
757         td = uhci_alloc_td(uhci);
758         if (!td)
759                 goto nomem;
760         *plink = cpu_to_le32(td->dma_handle);
761
762         /*
763          * It's IN if the pipe is an output pipe or we're not expecting
764          * data back.
765          */
766         destination &= ~TD_TOKEN_PID_MASK;
767         if (usb_pipeout(urb->pipe) || !urb->transfer_buffer_length)
768                 destination |= USB_PID_IN;
769         else
770                 destination |= USB_PID_OUT;
771
772         destination |= TD_TOKEN_TOGGLE;         /* End in Data1 */
773
774         status &= ~TD_CTRL_SPD;
775
776         uhci_add_td_to_urbp(td, urbp);
777         uhci_fill_td(td, status | TD_CTRL_IOC,
778                         destination | uhci_explen(0), 0);
779         plink = &td->link;
780
781         /*
782          * Build the new dummy TD and activate the old one
783          */
784         td = uhci_alloc_td(uhci);
785         if (!td)
786                 goto nomem;
787         *plink = cpu_to_le32(td->dma_handle);
788
789         uhci_fill_td(td, 0, USB_PID_OUT | uhci_explen(0), 0);
790         wmb();
791         qh->dummy_td->status |= __constant_cpu_to_le32(TD_CTRL_ACTIVE);
792         qh->dummy_td = td;
793
794         /* Low-speed transfers get a different queue, and won't hog the bus.
795          * Also, some devices enumerate better without FSBR; the easiest way
796          * to do that is to put URBs on the low-speed queue while the device
797          * isn't in the CONFIGURED state. */
798         if (urb->dev->speed == USB_SPEED_LOW ||
799                         urb->dev->state != USB_STATE_CONFIGURED)
800                 qh->skel = uhci->skel_ls_control_qh;
801         else {
802                 qh->skel = uhci->skel_fs_control_qh;
803                 uhci_add_fsbr(uhci, urb);
804         }
805
806         urb->actual_length = -8;        /* Account for the SETUP packet */
807         return 0;
808
809 nomem:
810         /* Remove the dummy TD from the td_list so it doesn't get freed */
811         uhci_remove_td_from_urbp(qh->dummy_td);
812         return -ENOMEM;
813 }
814
815 /*
816  * Common submit for bulk and interrupt
817  */
818 static int uhci_submit_common(struct uhci_hcd *uhci, struct urb *urb,
819                 struct uhci_qh *qh)
820 {
821         struct uhci_td *td;
822         unsigned long destination, status;
823         int maxsze = le16_to_cpu(qh->hep->desc.wMaxPacketSize);
824         int len = urb->transfer_buffer_length;
825         dma_addr_t data = urb->transfer_dma;
826         __le32 *plink;
827         struct urb_priv *urbp = urb->hcpriv;
828         unsigned int toggle;
829
830         if (len < 0)
831                 return -EINVAL;
832
833         /* The "pipe" thing contains the destination in bits 8--18 */
834         destination = (urb->pipe & PIPE_DEVEP_MASK) | usb_packetid(urb->pipe);
835         toggle = usb_gettoggle(urb->dev, usb_pipeendpoint(urb->pipe),
836                          usb_pipeout(urb->pipe));
837
838         /* 3 errors, dummy TD remains inactive */
839         status = uhci_maxerr(3);
840         if (urb->dev->speed == USB_SPEED_LOW)
841                 status |= TD_CTRL_LS;
842         if (usb_pipein(urb->pipe))
843                 status |= TD_CTRL_SPD;
844
845         /*
846          * Build the DATA TDs
847          */
848         plink = NULL;
849         td = qh->dummy_td;
850         do {    /* Allow zero length packets */
851                 int pktsze = maxsze;
852
853                 if (len <= pktsze) {            /* The last packet */
854                         pktsze = len;
855                         if (!(urb->transfer_flags & URB_SHORT_NOT_OK))
856                                 status &= ~TD_CTRL_SPD;
857                 }
858
859                 if (plink) {
860                         td = uhci_alloc_td(uhci);
861                         if (!td)
862                                 goto nomem;
863                         *plink = cpu_to_le32(td->dma_handle);
864                 }
865                 uhci_add_td_to_urbp(td, urbp);
866                 uhci_fill_td(td, status,
867                                 destination | uhci_explen(pktsze) |
868                                         (toggle << TD_TOKEN_TOGGLE_SHIFT),
869                                 data);
870                 plink = &td->link;
871                 status |= TD_CTRL_ACTIVE;
872
873                 data += pktsze;
874                 len -= maxsze;
875                 toggle ^= 1;
876         } while (len > 0);
877
878         /*
879          * URB_ZERO_PACKET means adding a 0-length packet, if direction
880          * is OUT and the transfer_length was an exact multiple of maxsze,
881          * hence (len = transfer_length - N * maxsze) == 0
882          * however, if transfer_length == 0, the zero packet was already
883          * prepared above.
884          */
885         if ((urb->transfer_flags & URB_ZERO_PACKET) &&
886                         usb_pipeout(urb->pipe) && len == 0 &&
887                         urb->transfer_buffer_length > 0) {
888                 td = uhci_alloc_td(uhci);
889                 if (!td)
890                         goto nomem;
891                 *plink = cpu_to_le32(td->dma_handle);
892
893                 uhci_add_td_to_urbp(td, urbp);
894                 uhci_fill_td(td, status,
895                                 destination | uhci_explen(0) |
896                                         (toggle << TD_TOKEN_TOGGLE_SHIFT),
897                                 data);
898                 plink = &td->link;
899
900                 toggle ^= 1;
901         }
902
903         /* Set the interrupt-on-completion flag on the last packet.
904          * A more-or-less typical 4 KB URB (= size of one memory page)
905          * will require about 3 ms to transfer; that's a little on the
906          * fast side but not enough to justify delaying an interrupt
907          * more than 2 or 3 URBs, so we will ignore the URB_NO_INTERRUPT
908          * flag setting. */
909         td->status |= __constant_cpu_to_le32(TD_CTRL_IOC);
910
911         /*
912          * Build the new dummy TD and activate the old one
913          */
914         td = uhci_alloc_td(uhci);
915         if (!td)
916                 goto nomem;
917         *plink = cpu_to_le32(td->dma_handle);
918
919         uhci_fill_td(td, 0, USB_PID_OUT | uhci_explen(0), 0);
920         wmb();
921         qh->dummy_td->status |= __constant_cpu_to_le32(TD_CTRL_ACTIVE);
922         qh->dummy_td = td;
923
924         usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
925                         usb_pipeout(urb->pipe), toggle);
926         return 0;
927
928 nomem:
929         /* Remove the dummy TD from the td_list so it doesn't get freed */
930         uhci_remove_td_from_urbp(qh->dummy_td);
931         return -ENOMEM;
932 }
933
934 static inline int uhci_submit_bulk(struct uhci_hcd *uhci, struct urb *urb,
935                 struct uhci_qh *qh)
936 {
937         int ret;
938
939         /* Can't have low-speed bulk transfers */
940         if (urb->dev->speed == USB_SPEED_LOW)
941                 return -EINVAL;
942
943         qh->skel = uhci->skel_bulk_qh;
944         ret = uhci_submit_common(uhci, urb, qh);
945         if (ret == 0)
946                 uhci_add_fsbr(uhci, urb);
947         return ret;
948 }
949
950 static int uhci_submit_interrupt(struct uhci_hcd *uhci, struct urb *urb,
951                 struct uhci_qh *qh)
952 {
953         int ret;
954
955         /* USB 1.1 interrupt transfers only involve one packet per interval.
956          * Drivers can submit URBs of any length, but longer ones will need
957          * multiple intervals to complete.
958          */
959
960         if (!qh->bandwidth_reserved) {
961                 int exponent;
962
963                 /* Figure out which power-of-two queue to use */
964                 for (exponent = 7; exponent >= 0; --exponent) {
965                         if ((1 << exponent) <= urb->interval)
966                                 break;
967                 }
968                 if (exponent < 0)
969                         return -EINVAL;
970                 qh->period = 1 << exponent;
971                 qh->skel = uhci->skelqh[UHCI_SKEL_INDEX(exponent)];
972
973                 /* For now, interrupt phase is fixed by the layout
974                  * of the QH lists. */
975                 qh->phase = (qh->period / 2) & (MAX_PHASE - 1);
976                 ret = uhci_check_bandwidth(uhci, qh);
977                 if (ret)
978                         return ret;
979         } else if (qh->period > urb->interval)
980                 return -EINVAL;         /* Can't decrease the period */
981
982         ret = uhci_submit_common(uhci, urb, qh);
983         if (ret == 0) {
984                 urb->interval = qh->period;
985                 if (!qh->bandwidth_reserved)
986                         uhci_reserve_bandwidth(uhci, qh);
987         }
988         return ret;
989 }
990
991 /*
992  * Fix up the data structures following a short transfer
993  */
994 static int uhci_fixup_short_transfer(struct uhci_hcd *uhci,
995                 struct uhci_qh *qh, struct urb_priv *urbp)
996 {
997         struct uhci_td *td;
998         struct list_head *tmp;
999         int ret;
1000
1001         td = list_entry(urbp->td_list.prev, struct uhci_td, list);
1002         if (qh->type == USB_ENDPOINT_XFER_CONTROL) {
1003
1004                 /* When a control transfer is short, we have to restart
1005                  * the queue at the status stage transaction, which is
1006                  * the last TD. */
1007                 WARN_ON(list_empty(&urbp->td_list));
1008                 qh->element = cpu_to_le32(td->dma_handle);
1009                 tmp = td->list.prev;
1010                 ret = -EINPROGRESS;
1011
1012         } else {
1013
1014                 /* When a bulk/interrupt transfer is short, we have to
1015                  * fix up the toggles of the following URBs on the queue
1016                  * before restarting the queue at the next URB. */
1017                 qh->initial_toggle = uhci_toggle(td_token(qh->post_td)) ^ 1;
1018                 uhci_fixup_toggles(qh, 1);
1019
1020                 if (list_empty(&urbp->td_list))
1021                         td = qh->post_td;
1022                 qh->element = td->link;
1023                 tmp = urbp->td_list.prev;
1024                 ret = 0;
1025         }
1026
1027         /* Remove all the TDs we skipped over, from tmp back to the start */
1028         while (tmp != &urbp->td_list) {
1029                 td = list_entry(tmp, struct uhci_td, list);
1030                 tmp = tmp->prev;
1031
1032                 uhci_remove_td_from_urbp(td);
1033                 uhci_free_td(uhci, td);
1034         }
1035         return ret;
1036 }
1037
1038 /*
1039  * Common result for control, bulk, and interrupt
1040  */
1041 static int uhci_result_common(struct uhci_hcd *uhci, struct urb *urb)
1042 {
1043         struct urb_priv *urbp = urb->hcpriv;
1044         struct uhci_qh *qh = urbp->qh;
1045         struct uhci_td *td, *tmp;
1046         unsigned status;
1047         int ret = 0;
1048
1049         list_for_each_entry_safe(td, tmp, &urbp->td_list, list) {
1050                 unsigned int ctrlstat;
1051                 int len;
1052
1053                 ctrlstat = td_status(td);
1054                 status = uhci_status_bits(ctrlstat);
1055                 if (status & TD_CTRL_ACTIVE)
1056                         return -EINPROGRESS;
1057
1058                 len = uhci_actual_length(ctrlstat);
1059                 urb->actual_length += len;
1060
1061                 if (status) {
1062                         ret = uhci_map_status(status,
1063                                         uhci_packetout(td_token(td)));
1064                         if ((debug == 1 && ret != -EPIPE) || debug > 1) {
1065                                 /* Some debugging code */
1066                                 dev_dbg(&urb->dev->dev,
1067                                                 "%s: failed with status %x\n",
1068                                                 __FUNCTION__, status);
1069
1070                                 if (debug > 1 && errbuf) {
1071                                         /* Print the chain for debugging */
1072                                         uhci_show_qh(urbp->qh, errbuf,
1073                                                         ERRBUF_LEN, 0);
1074                                         lprintk(errbuf);
1075                                 }
1076                         }
1077
1078                 } else if (len < uhci_expected_length(td_token(td))) {
1079
1080                         /* We received a short packet */
1081                         if (urb->transfer_flags & URB_SHORT_NOT_OK)
1082                                 ret = -EREMOTEIO;
1083
1084                         /* Fixup needed only if this isn't the URB's last TD */
1085                         else if (&td->list != urbp->td_list.prev)
1086                                 ret = 1;
1087                 }
1088
1089                 uhci_remove_td_from_urbp(td);
1090                 if (qh->post_td)
1091                         uhci_free_td(uhci, qh->post_td);
1092                 qh->post_td = td;
1093
1094                 if (ret != 0)
1095                         goto err;
1096         }
1097         return ret;
1098
1099 err:
1100         if (ret < 0) {
1101                 /* In case a control transfer gets an error
1102                  * during the setup stage */
1103                 urb->actual_length = max(urb->actual_length, 0);
1104
1105                 /* Note that the queue has stopped and save
1106                  * the next toggle value */
1107                 qh->element = UHCI_PTR_TERM;
1108                 qh->is_stopped = 1;
1109                 qh->needs_fixup = (qh->type != USB_ENDPOINT_XFER_CONTROL);
1110                 qh->initial_toggle = uhci_toggle(td_token(td)) ^
1111                                 (ret == -EREMOTEIO);
1112
1113         } else          /* Short packet received */
1114                 ret = uhci_fixup_short_transfer(uhci, qh, urbp);
1115         return ret;
1116 }
1117
1118 /*
1119  * Isochronous transfers
1120  */
1121 static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb,
1122                 struct uhci_qh *qh)
1123 {
1124         struct uhci_td *td = NULL;      /* Since urb->number_of_packets > 0 */
1125         int i, frame;
1126         unsigned long destination, status;
1127         struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;
1128
1129         /* Values must not be too big (could overflow below) */
1130         if (urb->interval >= UHCI_NUMFRAMES ||
1131                         urb->number_of_packets >= UHCI_NUMFRAMES)
1132                 return -EFBIG;
1133
1134         /* Check the period and figure out the starting frame number */
1135         if (!qh->bandwidth_reserved) {
1136                 qh->period = urb->interval;
1137                 if (urb->transfer_flags & URB_ISO_ASAP) {
1138                         qh->phase = -1;         /* Find the best phase */
1139                         i = uhci_check_bandwidth(uhci, qh);
1140                         if (i)
1141                                 return i;
1142
1143                         /* Allow a little time to allocate the TDs */
1144                         uhci_get_current_frame_number(uhci);
1145                         frame = uhci->frame_number + 10;
1146
1147                         /* Move forward to the first frame having the
1148                          * correct phase */
1149                         urb->start_frame = frame + ((qh->phase - frame) &
1150                                         (qh->period - 1));
1151                 } else {
1152                         i = urb->start_frame - uhci->last_iso_frame;
1153                         if (i <= 0 || i >= UHCI_NUMFRAMES)
1154                                 return -EINVAL;
1155                         qh->phase = urb->start_frame & (qh->period - 1);
1156                         i = uhci_check_bandwidth(uhci, qh);
1157                         if (i)
1158                                 return i;
1159                 }
1160
1161         } else if (qh->period != urb->interval) {
1162                 return -EINVAL;         /* Can't change the period */
1163
1164         } else {        /* Pick up where the last URB leaves off */
1165                 if (list_empty(&qh->queue)) {
1166                         frame = qh->iso_frame;
1167                 } else {
1168                         struct urb *lurb;
1169
1170                         lurb = list_entry(qh->queue.prev,
1171                                         struct urb_priv, node)->urb;
1172                         frame = lurb->start_frame +
1173                                         lurb->number_of_packets *
1174                                         lurb->interval;
1175                 }
1176                 if (urb->transfer_flags & URB_ISO_ASAP)
1177                         urb->start_frame = frame;
1178                 else if (urb->start_frame != frame)
1179                         return -EINVAL;
1180         }
1181
1182         /* Make sure we won't have to go too far into the future */
1183         if (uhci_frame_before_eq(uhci->last_iso_frame + UHCI_NUMFRAMES,
1184                         urb->start_frame + urb->number_of_packets *
1185                                 urb->interval))
1186                 return -EFBIG;
1187
1188         status = TD_CTRL_ACTIVE | TD_CTRL_IOS;
1189         destination = (urb->pipe & PIPE_DEVEP_MASK) | usb_packetid(urb->pipe);
1190
1191         for (i = 0; i < urb->number_of_packets; i++) {
1192                 td = uhci_alloc_td(uhci);
1193                 if (!td)
1194                         return -ENOMEM;
1195
1196                 uhci_add_td_to_urbp(td, urbp);
1197                 uhci_fill_td(td, status, destination |
1198                                 uhci_explen(urb->iso_frame_desc[i].length),
1199                                 urb->transfer_dma +
1200                                         urb->iso_frame_desc[i].offset);
1201         }
1202
1203         /* Set the interrupt-on-completion flag on the last packet. */
1204         td->status |= __constant_cpu_to_le32(TD_CTRL_IOC);
1205
1206         /* Add the TDs to the frame list */
1207         frame = urb->start_frame;
1208         list_for_each_entry(td, &urbp->td_list, list) {
1209                 uhci_insert_td_in_frame_list(uhci, td, frame);
1210                 frame += qh->period;
1211         }
1212
1213         if (list_empty(&qh->queue)) {
1214                 qh->iso_packet_desc = &urb->iso_frame_desc[0];
1215                 qh->iso_frame = urb->start_frame;
1216                 qh->iso_status = 0;
1217         }
1218
1219         qh->skel = uhci->skel_iso_qh;
1220         if (!qh->bandwidth_reserved)
1221                 uhci_reserve_bandwidth(uhci, qh);
1222         return 0;
1223 }
1224
1225 static int uhci_result_isochronous(struct uhci_hcd *uhci, struct urb *urb)
1226 {
1227         struct uhci_td *td, *tmp;
1228         struct urb_priv *urbp = urb->hcpriv;
1229         struct uhci_qh *qh = urbp->qh;
1230
1231         list_for_each_entry_safe(td, tmp, &urbp->td_list, list) {
1232                 unsigned int ctrlstat;
1233                 int status;
1234                 int actlength;
1235
1236                 if (uhci_frame_before_eq(uhci->cur_iso_frame, qh->iso_frame))
1237                         return -EINPROGRESS;
1238
1239                 uhci_remove_tds_from_frame(uhci, qh->iso_frame);
1240
1241                 ctrlstat = td_status(td);
1242                 if (ctrlstat & TD_CTRL_ACTIVE) {
1243                         status = -EXDEV;        /* TD was added too late? */
1244                 } else {
1245                         status = uhci_map_status(uhci_status_bits(ctrlstat),
1246                                         usb_pipeout(urb->pipe));
1247                         actlength = uhci_actual_length(ctrlstat);
1248
1249                         urb->actual_length += actlength;
1250                         qh->iso_packet_desc->actual_length = actlength;
1251                         qh->iso_packet_desc->status = status;
1252                 }
1253
1254                 if (status) {
1255                         urb->error_count++;
1256                         qh->iso_status = status;
1257                 }
1258
1259                 uhci_remove_td_from_urbp(td);
1260                 uhci_free_td(uhci, td);
1261                 qh->iso_frame += qh->period;
1262                 ++qh->iso_packet_desc;
1263         }
1264         return qh->iso_status;
1265 }
1266
1267 static int uhci_urb_enqueue(struct usb_hcd *hcd,
1268                 struct usb_host_endpoint *hep,
1269                 struct urb *urb, gfp_t mem_flags)
1270 {
1271         int ret;
1272         struct uhci_hcd *uhci = hcd_to_uhci(hcd);
1273         unsigned long flags;
1274         struct urb_priv *urbp;
1275         struct uhci_qh *qh;
1276
1277         spin_lock_irqsave(&uhci->lock, flags);
1278
1279         ret = urb->status;
1280         if (ret != -EINPROGRESS)                /* URB already unlinked! */
1281                 goto done;
1282
1283         ret = -ENOMEM;
1284         urbp = uhci_alloc_urb_priv(uhci, urb);
1285         if (!urbp)
1286                 goto done;
1287
1288         if (hep->hcpriv)
1289                 qh = (struct uhci_qh *) hep->hcpriv;
1290         else {
1291                 qh = uhci_alloc_qh(uhci, urb->dev, hep);
1292                 if (!qh)
1293                         goto err_no_qh;
1294         }
1295         urbp->qh = qh;
1296
1297         switch (qh->type) {
1298         case USB_ENDPOINT_XFER_CONTROL:
1299                 ret = uhci_submit_control(uhci, urb, qh);
1300                 break;
1301         case USB_ENDPOINT_XFER_BULK:
1302                 ret = uhci_submit_bulk(uhci, urb, qh);
1303                 break;
1304         case USB_ENDPOINT_XFER_INT:
1305                 ret = uhci_submit_interrupt(uhci, urb, qh);
1306                 break;
1307         case USB_ENDPOINT_XFER_ISOC:
1308                 urb->error_count = 0;
1309                 ret = uhci_submit_isochronous(uhci, urb, qh);
1310                 break;
1311         }
1312         if (ret != 0)
1313                 goto err_submit_failed;
1314
1315         /* Add this URB to the QH */
1316         urbp->qh = qh;
1317         list_add_tail(&urbp->node, &qh->queue);
1318
1319         /* If the new URB is the first and only one on this QH then either
1320          * the QH is new and idle or else it's unlinked and waiting to
1321          * become idle, so we can activate it right away.  But only if the
1322          * queue isn't stopped. */
1323         if (qh->queue.next == &urbp->node && !qh->is_stopped) {
1324                 uhci_activate_qh(uhci, qh);
1325                 uhci_urbp_wants_fsbr(uhci, urbp);
1326         }
1327         goto done;
1328
1329 err_submit_failed:
1330         if (qh->state == QH_STATE_IDLE)
1331                 uhci_make_qh_idle(uhci, qh);    /* Reclaim unused QH */
1332
1333 err_no_qh:
1334         uhci_free_urb_priv(uhci, urbp);
1335
1336 done:
1337         spin_unlock_irqrestore(&uhci->lock, flags);
1338         return ret;
1339 }
1340
1341 static int uhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb)
1342 {
1343         struct uhci_hcd *uhci = hcd_to_uhci(hcd);
1344         unsigned long flags;
1345         struct urb_priv *urbp;
1346         struct uhci_qh *qh;
1347
1348         spin_lock_irqsave(&uhci->lock, flags);
1349         urbp = urb->hcpriv;
1350         if (!urbp)                      /* URB was never linked! */
1351                 goto done;
1352         qh = urbp->qh;
1353
1354         /* Remove Isochronous TDs from the frame list ASAP */
1355         if (qh->type == USB_ENDPOINT_XFER_ISOC) {
1356                 uhci_unlink_isochronous_tds(uhci, urb);
1357                 mb();
1358
1359                 /* If the URB has already started, update the QH unlink time */
1360                 uhci_get_current_frame_number(uhci);
1361                 if (uhci_frame_before_eq(urb->start_frame, uhci->frame_number))
1362                         qh->unlink_frame = uhci->frame_number;
1363         }
1364
1365         uhci_unlink_qh(uhci, qh);
1366
1367 done:
1368         spin_unlock_irqrestore(&uhci->lock, flags);
1369         return 0;
1370 }
1371
1372 /*
1373  * Finish unlinking an URB and give it back
1374  */
1375 static void uhci_giveback_urb(struct uhci_hcd *uhci, struct uhci_qh *qh,
1376                 struct urb *urb)
1377 __releases(uhci->lock)
1378 __acquires(uhci->lock)
1379 {
1380         struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;
1381
1382         /* When giving back the first URB in an Isochronous queue,
1383          * reinitialize the QH's iso-related members for the next URB. */
1384         if (qh->type == USB_ENDPOINT_XFER_ISOC &&
1385                         urbp->node.prev == &qh->queue &&
1386                         urbp->node.next != &qh->queue) {
1387                 struct urb *nurb = list_entry(urbp->node.next,
1388                                 struct urb_priv, node)->urb;
1389
1390                 qh->iso_packet_desc = &nurb->iso_frame_desc[0];
1391                 qh->iso_frame = nurb->start_frame;
1392                 qh->iso_status = 0;
1393         }
1394
1395         /* Take the URB off the QH's queue.  If the queue is now empty,
1396          * this is a perfect time for a toggle fixup. */
1397         list_del_init(&urbp->node);
1398         if (list_empty(&qh->queue) && qh->needs_fixup) {
1399                 usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
1400                                 usb_pipeout(urb->pipe), qh->initial_toggle);
1401                 qh->needs_fixup = 0;
1402         }
1403
1404         uhci_free_urb_priv(uhci, urbp);
1405
1406         spin_unlock(&uhci->lock);
1407         usb_hcd_giveback_urb(uhci_to_hcd(uhci), urb);
1408         spin_lock(&uhci->lock);
1409
1410         /* If the queue is now empty, we can unlink the QH and give up its
1411          * reserved bandwidth. */
1412         if (list_empty(&qh->queue)) {
1413                 uhci_unlink_qh(uhci, qh);
1414                 if (qh->bandwidth_reserved)
1415                         uhci_release_bandwidth(uhci, qh);
1416         }
1417 }
1418
1419 /*
1420  * Scan the URBs in a QH's queue
1421  */
1422 #define QH_FINISHED_UNLINKING(qh)                       \
1423                 (qh->state == QH_STATE_UNLINKING &&     \
1424                 uhci->frame_number + uhci->is_stopped != qh->unlink_frame)
1425
1426 static void uhci_scan_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
1427 {
1428         struct urb_priv *urbp;
1429         struct urb *urb;
1430         int status;
1431
1432         while (!list_empty(&qh->queue)) {
1433                 urbp = list_entry(qh->queue.next, struct urb_priv, node);
1434                 urb = urbp->urb;
1435
1436                 if (qh->type == USB_ENDPOINT_XFER_ISOC)
1437                         status = uhci_result_isochronous(uhci, urb);
1438                 else
1439                         status = uhci_result_common(uhci, urb);
1440                 if (status == -EINPROGRESS)
1441                         break;
1442
1443                 spin_lock(&urb->lock);
1444                 if (urb->status == -EINPROGRESS)        /* Not dequeued */
1445                         urb->status = status;
1446                 else
1447                         status = ECONNRESET;            /* Not -ECONNRESET */
1448                 spin_unlock(&urb->lock);
1449
1450                 /* Dequeued but completed URBs can't be given back unless
1451                  * the QH is stopped or has finished unlinking. */
1452                 if (status == ECONNRESET) {
1453                         if (QH_FINISHED_UNLINKING(qh))
1454                                 qh->is_stopped = 1;
1455                         else if (!qh->is_stopped)
1456                                 return;
1457                 }
1458
1459                 uhci_giveback_urb(uhci, qh, urb);
1460                 if (status < 0 && qh->type != USB_ENDPOINT_XFER_ISOC)
1461                         break;
1462         }
1463
1464         /* If the QH is neither stopped nor finished unlinking (normal case),
1465          * our work here is done. */
1466         if (QH_FINISHED_UNLINKING(qh))
1467                 qh->is_stopped = 1;
1468         else if (!qh->is_stopped)
1469                 return;
1470
1471         /* Otherwise give back each of the dequeued URBs */
1472 restart:
1473         list_for_each_entry(urbp, &qh->queue, node) {
1474                 urb = urbp->urb;
1475                 if (urb->status != -EINPROGRESS) {
1476
1477                         /* Fix up the TD links and save the toggles for
1478                          * non-Isochronous queues.  For Isochronous queues,
1479                          * test for too-recent dequeues. */
1480                         if (!uhci_cleanup_queue(uhci, qh, urb)) {
1481                                 qh->is_stopped = 0;
1482                                 return;
1483                         }
1484                         uhci_giveback_urb(uhci, qh, urb);
1485                         goto restart;
1486                 }
1487         }
1488         qh->is_stopped = 0;
1489
1490         /* There are no more dequeued URBs.  If there are still URBs on the
1491          * queue, the QH can now be re-activated. */
1492         if (!list_empty(&qh->queue)) {
1493                 if (qh->needs_fixup)
1494                         uhci_fixup_toggles(qh, 0);
1495
1496                 /* If the first URB on the queue wants FSBR but its time
1497                  * limit has expired, set the next TD to interrupt on
1498                  * completion before reactivating the QH. */
1499                 urbp = list_entry(qh->queue.next, struct urb_priv, node);
1500                 if (urbp->fsbr && qh->wait_expired) {
1501                         struct uhci_td *td = list_entry(urbp->td_list.next,
1502                                         struct uhci_td, list);
1503
1504                         td->status |= __cpu_to_le32(TD_CTRL_IOC);
1505                 }
1506
1507                 uhci_activate_qh(uhci, qh);
1508         }
1509
1510         /* The queue is empty.  The QH can become idle if it is fully
1511          * unlinked. */
1512         else if (QH_FINISHED_UNLINKING(qh))
1513                 uhci_make_qh_idle(uhci, qh);
1514 }
1515
1516 /*
1517  * Check for queues that have made some forward progress.
1518  * Returns 0 if the queue is not Isochronous, is ACTIVE, and
1519  * has not advanced since last examined; 1 otherwise.
1520  *
1521  * Early Intel controllers have a bug which causes qh->element sometimes
1522  * not to advance when a TD completes successfully.  The queue remains
1523  * stuck on the inactive completed TD.  We detect such cases and advance
1524  * the element pointer by hand.
1525  */
1526 static int uhci_advance_check(struct uhci_hcd *uhci, struct uhci_qh *qh)
1527 {
1528         struct urb_priv *urbp = NULL;
1529         struct uhci_td *td;
1530         int ret = 1;
1531         unsigned status;
1532
1533         if (qh->type == USB_ENDPOINT_XFER_ISOC)
1534                 goto done;
1535
1536         /* Treat an UNLINKING queue as though it hasn't advanced.
1537          * This is okay because reactivation will treat it as though
1538          * it has advanced, and if it is going to become IDLE then
1539          * this doesn't matter anyway.  Furthermore it's possible
1540          * for an UNLINKING queue not to have any URBs at all, or
1541          * for its first URB not to have any TDs (if it was dequeued
1542          * just as it completed).  So it's not easy in any case to
1543          * test whether such queues have advanced. */
1544         if (qh->state != QH_STATE_ACTIVE) {
1545                 urbp = NULL;
1546                 status = 0;
1547
1548         } else {
1549                 urbp = list_entry(qh->queue.next, struct urb_priv, node);
1550                 td = list_entry(urbp->td_list.next, struct uhci_td, list);
1551                 status = td_status(td);
1552                 if (!(status & TD_CTRL_ACTIVE)) {
1553
1554                         /* We're okay, the queue has advanced */
1555                         qh->wait_expired = 0;
1556                         qh->advance_jiffies = jiffies;
1557                         goto done;
1558                 }
1559                 ret = 0;
1560         }
1561
1562         /* The queue hasn't advanced; check for timeout */
1563         if (qh->wait_expired)
1564                 goto done;
1565
1566         if (time_after(jiffies, qh->advance_jiffies + QH_WAIT_TIMEOUT)) {
1567
1568                 /* Detect the Intel bug and work around it */
1569                 if (qh->post_td && qh_element(qh) ==
1570                                 cpu_to_le32(qh->post_td->dma_handle)) {
1571                         qh->element = qh->post_td->link;
1572                         qh->advance_jiffies = jiffies;
1573                         ret = 1;
1574                         goto done;
1575                 }
1576
1577                 qh->wait_expired = 1;
1578
1579                 /* If the current URB wants FSBR, unlink it temporarily
1580                  * so that we can safely set the next TD to interrupt on
1581                  * completion.  That way we'll know as soon as the queue
1582                  * starts moving again. */
1583                 if (urbp && urbp->fsbr && !(status & TD_CTRL_IOC))
1584                         uhci_unlink_qh(uhci, qh);
1585
1586         } else {
1587                 /* Unmoving but not-yet-expired queues keep FSBR alive */
1588                 if (urbp)
1589                         uhci_urbp_wants_fsbr(uhci, urbp);
1590         }
1591
1592 done:
1593         return ret;
1594 }
1595
1596 /*
1597  * Process events in the schedule, but only in one thread at a time
1598  */
1599 static void uhci_scan_schedule(struct uhci_hcd *uhci)
1600 {
1601         int i;
1602         struct uhci_qh *qh;
1603
1604         /* Don't allow re-entrant calls */
1605         if (uhci->scan_in_progress) {
1606                 uhci->need_rescan = 1;
1607                 return;
1608         }
1609         uhci->scan_in_progress = 1;
1610 rescan:
1611         uhci->need_rescan = 0;
1612         uhci->fsbr_is_wanted = 0;
1613
1614         uhci_clear_next_interrupt(uhci);
1615         uhci_get_current_frame_number(uhci);
1616         uhci->cur_iso_frame = uhci->frame_number;
1617
1618         /* Go through all the QH queues and process the URBs in each one */
1619         for (i = 0; i < UHCI_NUM_SKELQH - 1; ++i) {
1620                 uhci->next_qh = list_entry(uhci->skelqh[i]->node.next,
1621                                 struct uhci_qh, node);
1622                 while ((qh = uhci->next_qh) != uhci->skelqh[i]) {
1623                         uhci->next_qh = list_entry(qh->node.next,
1624                                         struct uhci_qh, node);
1625
1626                         if (uhci_advance_check(uhci, qh)) {
1627                                 uhci_scan_qh(uhci, qh);
1628                                 if (qh->state == QH_STATE_ACTIVE) {
1629                                         uhci_urbp_wants_fsbr(uhci,
1630         list_entry(qh->queue.next, struct urb_priv, node));
1631                                 }
1632                         }
1633                 }
1634         }
1635
1636         uhci->last_iso_frame = uhci->cur_iso_frame;
1637         if (uhci->need_rescan)
1638                 goto rescan;
1639         uhci->scan_in_progress = 0;
1640
1641         if (uhci->fsbr_is_on && !uhci->fsbr_is_wanted &&
1642                         !uhci->fsbr_expiring) {
1643                 uhci->fsbr_expiring = 1;
1644                 mod_timer(&uhci->fsbr_timer, jiffies + FSBR_OFF_DELAY);
1645         }
1646
1647         if (list_empty(&uhci->skel_unlink_qh->node))
1648                 uhci_clear_next_interrupt(uhci);
1649         else
1650                 uhci_set_next_interrupt(uhci);
1651 }