UHCI: fix bandwidth allocation
[pandora-kernel.git] / 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_alloc(uhci_up_cachep, GFP_ATOMIC);
628         if (!urbp)
629                 return NULL;
630
631         memset((void *)urbp, 0, sizeof(*urbp));
632
633         urbp->urb = urb;
634         urb->hcpriv = urbp;
635         
636         INIT_LIST_HEAD(&urbp->node);
637         INIT_LIST_HEAD(&urbp->td_list);
638
639         return urbp;
640 }
641
642 static void uhci_free_urb_priv(struct uhci_hcd *uhci,
643                 struct urb_priv *urbp)
644 {
645         struct uhci_td *td, *tmp;
646
647         if (!list_empty(&urbp->node))
648                 dev_warn(uhci_dev(uhci), "urb %p still on QH's list!\n",
649                                 urbp->urb);
650
651         list_for_each_entry_safe(td, tmp, &urbp->td_list, list) {
652                 uhci_remove_td_from_urbp(td);
653                 uhci_free_td(uhci, td);
654         }
655
656         urbp->urb->hcpriv = NULL;
657         kmem_cache_free(uhci_up_cachep, urbp);
658 }
659
660 /*
661  * Map status to standard result codes
662  *
663  * <status> is (td_status(td) & 0xF60000), a.k.a.
664  * uhci_status_bits(td_status(td)).
665  * Note: <status> does not include the TD_CTRL_NAK bit.
666  * <dir_out> is True for output TDs and False for input TDs.
667  */
668 static int uhci_map_status(int status, int dir_out)
669 {
670         if (!status)
671                 return 0;
672         if (status & TD_CTRL_BITSTUFF)                  /* Bitstuff error */
673                 return -EPROTO;
674         if (status & TD_CTRL_CRCTIMEO) {                /* CRC/Timeout */
675                 if (dir_out)
676                         return -EPROTO;
677                 else
678                         return -EILSEQ;
679         }
680         if (status & TD_CTRL_BABBLE)                    /* Babble */
681                 return -EOVERFLOW;
682         if (status & TD_CTRL_DBUFERR)                   /* Buffer error */
683                 return -ENOSR;
684         if (status & TD_CTRL_STALLED)                   /* Stalled */
685                 return -EPIPE;
686         return 0;
687 }
688
689 /*
690  * Control transfers
691  */
692 static int uhci_submit_control(struct uhci_hcd *uhci, struct urb *urb,
693                 struct uhci_qh *qh)
694 {
695         struct uhci_td *td;
696         unsigned long destination, status;
697         int maxsze = le16_to_cpu(qh->hep->desc.wMaxPacketSize);
698         int len = urb->transfer_buffer_length;
699         dma_addr_t data = urb->transfer_dma;
700         __le32 *plink;
701         struct urb_priv *urbp = urb->hcpriv;
702
703         /* The "pipe" thing contains the destination in bits 8--18 */
704         destination = (urb->pipe & PIPE_DEVEP_MASK) | USB_PID_SETUP;
705
706         /* 3 errors, dummy TD remains inactive */
707         status = uhci_maxerr(3);
708         if (urb->dev->speed == USB_SPEED_LOW)
709                 status |= TD_CTRL_LS;
710
711         /*
712          * Build the TD for the control request setup packet
713          */
714         td = qh->dummy_td;
715         uhci_add_td_to_urbp(td, urbp);
716         uhci_fill_td(td, status, destination | uhci_explen(8),
717                         urb->setup_dma);
718         plink = &td->link;
719         status |= TD_CTRL_ACTIVE;
720
721         /*
722          * If direction is "send", change the packet ID from SETUP (0x2D)
723          * to OUT (0xE1).  Else change it from SETUP to IN (0x69) and
724          * set Short Packet Detect (SPD) for all data packets.
725          */
726         if (usb_pipeout(urb->pipe))
727                 destination ^= (USB_PID_SETUP ^ USB_PID_OUT);
728         else {
729                 destination ^= (USB_PID_SETUP ^ USB_PID_IN);
730                 status |= TD_CTRL_SPD;
731         }
732
733         /*
734          * Build the DATA TDs
735          */
736         while (len > 0) {
737                 int pktsze = min(len, maxsze);
738
739                 td = uhci_alloc_td(uhci);
740                 if (!td)
741                         goto nomem;
742                 *plink = cpu_to_le32(td->dma_handle);
743
744                 /* Alternate Data0/1 (start with Data1) */
745                 destination ^= TD_TOKEN_TOGGLE;
746         
747                 uhci_add_td_to_urbp(td, urbp);
748                 uhci_fill_td(td, status, destination | uhci_explen(pktsze),
749                                 data);
750                 plink = &td->link;
751
752                 data += pktsze;
753                 len -= pktsze;
754         }
755
756         /*
757          * Build the final TD for control status 
758          */
759         td = uhci_alloc_td(uhci);
760         if (!td)
761                 goto nomem;
762         *plink = cpu_to_le32(td->dma_handle);
763
764         /*
765          * It's IN if the pipe is an output pipe or we're not expecting
766          * data back.
767          */
768         destination &= ~TD_TOKEN_PID_MASK;
769         if (usb_pipeout(urb->pipe) || !urb->transfer_buffer_length)
770                 destination |= USB_PID_IN;
771         else
772                 destination |= USB_PID_OUT;
773
774         destination |= TD_TOKEN_TOGGLE;         /* End in Data1 */
775
776         status &= ~TD_CTRL_SPD;
777
778         uhci_add_td_to_urbp(td, urbp);
779         uhci_fill_td(td, status | TD_CTRL_IOC,
780                         destination | uhci_explen(0), 0);
781         plink = &td->link;
782
783         /*
784          * Build the new dummy TD and activate the old one
785          */
786         td = uhci_alloc_td(uhci);
787         if (!td)
788                 goto nomem;
789         *plink = cpu_to_le32(td->dma_handle);
790
791         uhci_fill_td(td, 0, USB_PID_OUT | uhci_explen(0), 0);
792         wmb();
793         qh->dummy_td->status |= __constant_cpu_to_le32(TD_CTRL_ACTIVE);
794         qh->dummy_td = td;
795
796         /* Low-speed transfers get a different queue, and won't hog the bus.
797          * Also, some devices enumerate better without FSBR; the easiest way
798          * to do that is to put URBs on the low-speed queue while the device
799          * isn't in the CONFIGURED state. */
800         if (urb->dev->speed == USB_SPEED_LOW ||
801                         urb->dev->state != USB_STATE_CONFIGURED)
802                 qh->skel = uhci->skel_ls_control_qh;
803         else {
804                 qh->skel = uhci->skel_fs_control_qh;
805                 uhci_add_fsbr(uhci, urb);
806         }
807
808         urb->actual_length = -8;        /* Account for the SETUP packet */
809         return 0;
810
811 nomem:
812         /* Remove the dummy TD from the td_list so it doesn't get freed */
813         uhci_remove_td_from_urbp(qh->dummy_td);
814         return -ENOMEM;
815 }
816
817 /*
818  * Common submit for bulk and interrupt
819  */
820 static int uhci_submit_common(struct uhci_hcd *uhci, struct urb *urb,
821                 struct uhci_qh *qh)
822 {
823         struct uhci_td *td;
824         unsigned long destination, status;
825         int maxsze = le16_to_cpu(qh->hep->desc.wMaxPacketSize);
826         int len = urb->transfer_buffer_length;
827         dma_addr_t data = urb->transfer_dma;
828         __le32 *plink;
829         struct urb_priv *urbp = urb->hcpriv;
830         unsigned int toggle;
831
832         if (len < 0)
833                 return -EINVAL;
834
835         /* The "pipe" thing contains the destination in bits 8--18 */
836         destination = (urb->pipe & PIPE_DEVEP_MASK) | usb_packetid(urb->pipe);
837         toggle = usb_gettoggle(urb->dev, usb_pipeendpoint(urb->pipe),
838                          usb_pipeout(urb->pipe));
839
840         /* 3 errors, dummy TD remains inactive */
841         status = uhci_maxerr(3);
842         if (urb->dev->speed == USB_SPEED_LOW)
843                 status |= TD_CTRL_LS;
844         if (usb_pipein(urb->pipe))
845                 status |= TD_CTRL_SPD;
846
847         /*
848          * Build the DATA TDs
849          */
850         plink = NULL;
851         td = qh->dummy_td;
852         do {    /* Allow zero length packets */
853                 int pktsze = maxsze;
854
855                 if (len <= pktsze) {            /* The last packet */
856                         pktsze = len;
857                         if (!(urb->transfer_flags & URB_SHORT_NOT_OK))
858                                 status &= ~TD_CTRL_SPD;
859                 }
860
861                 if (plink) {
862                         td = uhci_alloc_td(uhci);
863                         if (!td)
864                                 goto nomem;
865                         *plink = cpu_to_le32(td->dma_handle);
866                 }
867                 uhci_add_td_to_urbp(td, urbp);
868                 uhci_fill_td(td, status,
869                                 destination | uhci_explen(pktsze) |
870                                         (toggle << TD_TOKEN_TOGGLE_SHIFT),
871                                 data);
872                 plink = &td->link;
873                 status |= TD_CTRL_ACTIVE;
874
875                 data += pktsze;
876                 len -= maxsze;
877                 toggle ^= 1;
878         } while (len > 0);
879
880         /*
881          * URB_ZERO_PACKET means adding a 0-length packet, if direction
882          * is OUT and the transfer_length was an exact multiple of maxsze,
883          * hence (len = transfer_length - N * maxsze) == 0
884          * however, if transfer_length == 0, the zero packet was already
885          * prepared above.
886          */
887         if ((urb->transfer_flags & URB_ZERO_PACKET) &&
888                         usb_pipeout(urb->pipe) && len == 0 &&
889                         urb->transfer_buffer_length > 0) {
890                 td = uhci_alloc_td(uhci);
891                 if (!td)
892                         goto nomem;
893                 *plink = cpu_to_le32(td->dma_handle);
894
895                 uhci_add_td_to_urbp(td, urbp);
896                 uhci_fill_td(td, status,
897                                 destination | uhci_explen(0) |
898                                         (toggle << TD_TOKEN_TOGGLE_SHIFT),
899                                 data);
900                 plink = &td->link;
901
902                 toggle ^= 1;
903         }
904
905         /* Set the interrupt-on-completion flag on the last packet.
906          * A more-or-less typical 4 KB URB (= size of one memory page)
907          * will require about 3 ms to transfer; that's a little on the
908          * fast side but not enough to justify delaying an interrupt
909          * more than 2 or 3 URBs, so we will ignore the URB_NO_INTERRUPT
910          * flag setting. */
911         td->status |= __constant_cpu_to_le32(TD_CTRL_IOC);
912
913         /*
914          * Build the new dummy TD and activate the old one
915          */
916         td = uhci_alloc_td(uhci);
917         if (!td)
918                 goto nomem;
919         *plink = cpu_to_le32(td->dma_handle);
920
921         uhci_fill_td(td, 0, USB_PID_OUT | uhci_explen(0), 0);
922         wmb();
923         qh->dummy_td->status |= __constant_cpu_to_le32(TD_CTRL_ACTIVE);
924         qh->dummy_td = td;
925
926         usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
927                         usb_pipeout(urb->pipe), toggle);
928         return 0;
929
930 nomem:
931         /* Remove the dummy TD from the td_list so it doesn't get freed */
932         uhci_remove_td_from_urbp(qh->dummy_td);
933         return -ENOMEM;
934 }
935
936 static inline int uhci_submit_bulk(struct uhci_hcd *uhci, struct urb *urb,
937                 struct uhci_qh *qh)
938 {
939         int ret;
940
941         /* Can't have low-speed bulk transfers */
942         if (urb->dev->speed == USB_SPEED_LOW)
943                 return -EINVAL;
944
945         qh->skel = uhci->skel_bulk_qh;
946         ret = uhci_submit_common(uhci, urb, qh);
947         if (ret == 0)
948                 uhci_add_fsbr(uhci, urb);
949         return ret;
950 }
951
952 static int uhci_submit_interrupt(struct uhci_hcd *uhci, struct urb *urb,
953                 struct uhci_qh *qh)
954 {
955         int ret;
956
957         /* USB 1.1 interrupt transfers only involve one packet per interval.
958          * Drivers can submit URBs of any length, but longer ones will need
959          * multiple intervals to complete.
960          */
961
962         if (!qh->bandwidth_reserved) {
963                 int exponent;
964
965                 /* Figure out which power-of-two queue to use */
966                 for (exponent = 7; exponent >= 0; --exponent) {
967                         if ((1 << exponent) <= urb->interval)
968                                 break;
969                 }
970                 if (exponent < 0)
971                         return -EINVAL;
972                 qh->period = 1 << exponent;
973                 qh->skel = uhci->skelqh[UHCI_SKEL_INDEX(exponent)];
974
975                 /* For now, interrupt phase is fixed by the layout
976                  * of the QH lists. */
977                 qh->phase = (qh->period / 2) & (MAX_PHASE - 1);
978                 ret = uhci_check_bandwidth(uhci, qh);
979                 if (ret)
980                         return ret;
981         } else if (qh->period > urb->interval)
982                 return -EINVAL;         /* Can't decrease the period */
983
984         ret = uhci_submit_common(uhci, urb, qh);
985         if (ret == 0) {
986                 urb->interval = qh->period;
987                 if (!qh->bandwidth_reserved)
988                         uhci_reserve_bandwidth(uhci, qh);
989         }
990         return ret;
991 }
992
993 /*
994  * Fix up the data structures following a short transfer
995  */
996 static int uhci_fixup_short_transfer(struct uhci_hcd *uhci,
997                 struct uhci_qh *qh, struct urb_priv *urbp)
998 {
999         struct uhci_td *td;
1000         struct list_head *tmp;
1001         int ret;
1002
1003         td = list_entry(urbp->td_list.prev, struct uhci_td, list);
1004         if (qh->type == USB_ENDPOINT_XFER_CONTROL) {
1005
1006                 /* When a control transfer is short, we have to restart
1007                  * the queue at the status stage transaction, which is
1008                  * the last TD. */
1009                 WARN_ON(list_empty(&urbp->td_list));
1010                 qh->element = cpu_to_le32(td->dma_handle);
1011                 tmp = td->list.prev;
1012                 ret = -EINPROGRESS;
1013
1014         } else {
1015
1016                 /* When a bulk/interrupt transfer is short, we have to
1017                  * fix up the toggles of the following URBs on the queue
1018                  * before restarting the queue at the next URB. */
1019                 qh->initial_toggle = uhci_toggle(td_token(qh->post_td)) ^ 1;
1020                 uhci_fixup_toggles(qh, 1);
1021
1022                 if (list_empty(&urbp->td_list))
1023                         td = qh->post_td;
1024                 qh->element = td->link;
1025                 tmp = urbp->td_list.prev;
1026                 ret = 0;
1027         }
1028
1029         /* Remove all the TDs we skipped over, from tmp back to the start */
1030         while (tmp != &urbp->td_list) {
1031                 td = list_entry(tmp, struct uhci_td, list);
1032                 tmp = tmp->prev;
1033
1034                 uhci_remove_td_from_urbp(td);
1035                 uhci_free_td(uhci, td);
1036         }
1037         return ret;
1038 }
1039
1040 /*
1041  * Common result for control, bulk, and interrupt
1042  */
1043 static int uhci_result_common(struct uhci_hcd *uhci, struct urb *urb)
1044 {
1045         struct urb_priv *urbp = urb->hcpriv;
1046         struct uhci_qh *qh = urbp->qh;
1047         struct uhci_td *td, *tmp;
1048         unsigned status;
1049         int ret = 0;
1050
1051         list_for_each_entry_safe(td, tmp, &urbp->td_list, list) {
1052                 unsigned int ctrlstat;
1053                 int len;
1054
1055                 ctrlstat = td_status(td);
1056                 status = uhci_status_bits(ctrlstat);
1057                 if (status & TD_CTRL_ACTIVE)
1058                         return -EINPROGRESS;
1059
1060                 len = uhci_actual_length(ctrlstat);
1061                 urb->actual_length += len;
1062
1063                 if (status) {
1064                         ret = uhci_map_status(status,
1065                                         uhci_packetout(td_token(td)));
1066                         if ((debug == 1 && ret != -EPIPE) || debug > 1) {
1067                                 /* Some debugging code */
1068                                 dev_dbg(&urb->dev->dev,
1069                                                 "%s: failed with status %x\n",
1070                                                 __FUNCTION__, status);
1071
1072                                 if (debug > 1 && errbuf) {
1073                                         /* Print the chain for debugging */
1074                                         uhci_show_qh(urbp->qh, errbuf,
1075                                                         ERRBUF_LEN, 0);
1076                                         lprintk(errbuf);
1077                                 }
1078                         }
1079
1080                 } else if (len < uhci_expected_length(td_token(td))) {
1081
1082                         /* We received a short packet */
1083                         if (urb->transfer_flags & URB_SHORT_NOT_OK)
1084                                 ret = -EREMOTEIO;
1085
1086                         /* Fixup needed only if this isn't the URB's last TD */
1087                         else if (&td->list != urbp->td_list.prev)
1088                                 ret = 1;
1089                 }
1090
1091                 uhci_remove_td_from_urbp(td);
1092                 if (qh->post_td)
1093                         uhci_free_td(uhci, qh->post_td);
1094                 qh->post_td = td;
1095
1096                 if (ret != 0)
1097                         goto err;
1098         }
1099         return ret;
1100
1101 err:
1102         if (ret < 0) {
1103                 /* In case a control transfer gets an error
1104                  * during the setup stage */
1105                 urb->actual_length = max(urb->actual_length, 0);
1106
1107                 /* Note that the queue has stopped and save
1108                  * the next toggle value */
1109                 qh->element = UHCI_PTR_TERM;
1110                 qh->is_stopped = 1;
1111                 qh->needs_fixup = (qh->type != USB_ENDPOINT_XFER_CONTROL);
1112                 qh->initial_toggle = uhci_toggle(td_token(td)) ^
1113                                 (ret == -EREMOTEIO);
1114
1115         } else          /* Short packet received */
1116                 ret = uhci_fixup_short_transfer(uhci, qh, urbp);
1117         return ret;
1118 }
1119
1120 /*
1121  * Isochronous transfers
1122  */
1123 static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb,
1124                 struct uhci_qh *qh)
1125 {
1126         struct uhci_td *td = NULL;      /* Since urb->number_of_packets > 0 */
1127         int i, frame;
1128         unsigned long destination, status;
1129         struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;
1130
1131         /* Values must not be too big (could overflow below) */
1132         if (urb->interval >= UHCI_NUMFRAMES ||
1133                         urb->number_of_packets >= UHCI_NUMFRAMES)
1134                 return -EFBIG;
1135
1136         /* Check the period and figure out the starting frame number */
1137         if (!qh->bandwidth_reserved) {
1138                 qh->period = urb->interval;
1139                 if (urb->transfer_flags & URB_ISO_ASAP) {
1140                         qh->phase = -1;         /* Find the best phase */
1141                         i = uhci_check_bandwidth(uhci, qh);
1142                         if (i)
1143                                 return i;
1144
1145                         /* Allow a little time to allocate the TDs */
1146                         uhci_get_current_frame_number(uhci);
1147                         frame = uhci->frame_number + 10;
1148
1149                         /* Move forward to the first frame having the
1150                          * correct phase */
1151                         urb->start_frame = frame + ((qh->phase - frame) &
1152                                         (qh->period - 1));
1153                 } else {
1154                         i = urb->start_frame - uhci->last_iso_frame;
1155                         if (i <= 0 || i >= UHCI_NUMFRAMES)
1156                                 return -EINVAL;
1157                         qh->phase = urb->start_frame & (qh->period - 1);
1158                         i = uhci_check_bandwidth(uhci, qh);
1159                         if (i)
1160                                 return i;
1161                 }
1162
1163         } else if (qh->period != urb->interval) {
1164                 return -EINVAL;         /* Can't change the period */
1165
1166         } else {        /* Pick up where the last URB leaves off */
1167                 if (list_empty(&qh->queue)) {
1168                         frame = qh->iso_frame;
1169                 } else {
1170                         struct urb *lurb;
1171
1172                         lurb = list_entry(qh->queue.prev,
1173                                         struct urb_priv, node)->urb;
1174                         frame = lurb->start_frame +
1175                                         lurb->number_of_packets *
1176                                         lurb->interval;
1177                 }
1178                 if (urb->transfer_flags & URB_ISO_ASAP)
1179                         urb->start_frame = frame;
1180                 else if (urb->start_frame != frame)
1181                         return -EINVAL;
1182         }
1183
1184         /* Make sure we won't have to go too far into the future */
1185         if (uhci_frame_before_eq(uhci->last_iso_frame + UHCI_NUMFRAMES,
1186                         urb->start_frame + urb->number_of_packets *
1187                                 urb->interval))
1188                 return -EFBIG;
1189
1190         status = TD_CTRL_ACTIVE | TD_CTRL_IOS;
1191         destination = (urb->pipe & PIPE_DEVEP_MASK) | usb_packetid(urb->pipe);
1192
1193         for (i = 0; i < urb->number_of_packets; i++) {
1194                 td = uhci_alloc_td(uhci);
1195                 if (!td)
1196                         return -ENOMEM;
1197
1198                 uhci_add_td_to_urbp(td, urbp);
1199                 uhci_fill_td(td, status, destination |
1200                                 uhci_explen(urb->iso_frame_desc[i].length),
1201                                 urb->transfer_dma +
1202                                         urb->iso_frame_desc[i].offset);
1203         }
1204
1205         /* Set the interrupt-on-completion flag on the last packet. */
1206         td->status |= __constant_cpu_to_le32(TD_CTRL_IOC);
1207
1208         /* Add the TDs to the frame list */
1209         frame = urb->start_frame;
1210         list_for_each_entry(td, &urbp->td_list, list) {
1211                 uhci_insert_td_in_frame_list(uhci, td, frame);
1212                 frame += qh->period;
1213         }
1214
1215         if (list_empty(&qh->queue)) {
1216                 qh->iso_packet_desc = &urb->iso_frame_desc[0];
1217                 qh->iso_frame = urb->start_frame;
1218                 qh->iso_status = 0;
1219         }
1220
1221         qh->skel = uhci->skel_iso_qh;
1222         if (!qh->bandwidth_reserved)
1223                 uhci_reserve_bandwidth(uhci, qh);
1224         return 0;
1225 }
1226
1227 static int uhci_result_isochronous(struct uhci_hcd *uhci, struct urb *urb)
1228 {
1229         struct uhci_td *td, *tmp;
1230         struct urb_priv *urbp = urb->hcpriv;
1231         struct uhci_qh *qh = urbp->qh;
1232
1233         list_for_each_entry_safe(td, tmp, &urbp->td_list, list) {
1234                 unsigned int ctrlstat;
1235                 int status;
1236                 int actlength;
1237
1238                 if (uhci_frame_before_eq(uhci->cur_iso_frame, qh->iso_frame))
1239                         return -EINPROGRESS;
1240
1241                 uhci_remove_tds_from_frame(uhci, qh->iso_frame);
1242
1243                 ctrlstat = td_status(td);
1244                 if (ctrlstat & TD_CTRL_ACTIVE) {
1245                         status = -EXDEV;        /* TD was added too late? */
1246                 } else {
1247                         status = uhci_map_status(uhci_status_bits(ctrlstat),
1248                                         usb_pipeout(urb->pipe));
1249                         actlength = uhci_actual_length(ctrlstat);
1250
1251                         urb->actual_length += actlength;
1252                         qh->iso_packet_desc->actual_length = actlength;
1253                         qh->iso_packet_desc->status = status;
1254                 }
1255
1256                 if (status) {
1257                         urb->error_count++;
1258                         qh->iso_status = status;
1259                 }
1260
1261                 uhci_remove_td_from_urbp(td);
1262                 uhci_free_td(uhci, td);
1263                 qh->iso_frame += qh->period;
1264                 ++qh->iso_packet_desc;
1265         }
1266         return qh->iso_status;
1267 }
1268
1269 static int uhci_urb_enqueue(struct usb_hcd *hcd,
1270                 struct usb_host_endpoint *hep,
1271                 struct urb *urb, gfp_t mem_flags)
1272 {
1273         int ret;
1274         struct uhci_hcd *uhci = hcd_to_uhci(hcd);
1275         unsigned long flags;
1276         struct urb_priv *urbp;
1277         struct uhci_qh *qh;
1278
1279         spin_lock_irqsave(&uhci->lock, flags);
1280
1281         ret = urb->status;
1282         if (ret != -EINPROGRESS)                /* URB already unlinked! */
1283                 goto done;
1284
1285         ret = -ENOMEM;
1286         urbp = uhci_alloc_urb_priv(uhci, urb);
1287         if (!urbp)
1288                 goto done;
1289
1290         if (hep->hcpriv)
1291                 qh = (struct uhci_qh *) hep->hcpriv;
1292         else {
1293                 qh = uhci_alloc_qh(uhci, urb->dev, hep);
1294                 if (!qh)
1295                         goto err_no_qh;
1296         }
1297         urbp->qh = qh;
1298
1299         switch (qh->type) {
1300         case USB_ENDPOINT_XFER_CONTROL:
1301                 ret = uhci_submit_control(uhci, urb, qh);
1302                 break;
1303         case USB_ENDPOINT_XFER_BULK:
1304                 ret = uhci_submit_bulk(uhci, urb, qh);
1305                 break;
1306         case USB_ENDPOINT_XFER_INT:
1307                 ret = uhci_submit_interrupt(uhci, urb, qh);
1308                 break;
1309         case USB_ENDPOINT_XFER_ISOC:
1310                 urb->error_count = 0;
1311                 ret = uhci_submit_isochronous(uhci, urb, qh);
1312                 break;
1313         }
1314         if (ret != 0)
1315                 goto err_submit_failed;
1316
1317         /* Add this URB to the QH */
1318         urbp->qh = qh;
1319         list_add_tail(&urbp->node, &qh->queue);
1320
1321         /* If the new URB is the first and only one on this QH then either
1322          * the QH is new and idle or else it's unlinked and waiting to
1323          * become idle, so we can activate it right away.  But only if the
1324          * queue isn't stopped. */
1325         if (qh->queue.next == &urbp->node && !qh->is_stopped) {
1326                 uhci_activate_qh(uhci, qh);
1327                 uhci_urbp_wants_fsbr(uhci, urbp);
1328         }
1329         goto done;
1330
1331 err_submit_failed:
1332         if (qh->state == QH_STATE_IDLE)
1333                 uhci_make_qh_idle(uhci, qh);    /* Reclaim unused QH */
1334
1335 err_no_qh:
1336         uhci_free_urb_priv(uhci, urbp);
1337
1338 done:
1339         spin_unlock_irqrestore(&uhci->lock, flags);
1340         return ret;
1341 }
1342
1343 static int uhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb)
1344 {
1345         struct uhci_hcd *uhci = hcd_to_uhci(hcd);
1346         unsigned long flags;
1347         struct urb_priv *urbp;
1348         struct uhci_qh *qh;
1349
1350         spin_lock_irqsave(&uhci->lock, flags);
1351         urbp = urb->hcpriv;
1352         if (!urbp)                      /* URB was never linked! */
1353                 goto done;
1354         qh = urbp->qh;
1355
1356         /* Remove Isochronous TDs from the frame list ASAP */
1357         if (qh->type == USB_ENDPOINT_XFER_ISOC) {
1358                 uhci_unlink_isochronous_tds(uhci, urb);
1359                 mb();
1360
1361                 /* If the URB has already started, update the QH unlink time */
1362                 uhci_get_current_frame_number(uhci);
1363                 if (uhci_frame_before_eq(urb->start_frame, uhci->frame_number))
1364                         qh->unlink_frame = uhci->frame_number;
1365         }
1366
1367         uhci_unlink_qh(uhci, qh);
1368
1369 done:
1370         spin_unlock_irqrestore(&uhci->lock, flags);
1371         return 0;
1372 }
1373
1374 /*
1375  * Finish unlinking an URB and give it back
1376  */
1377 static void uhci_giveback_urb(struct uhci_hcd *uhci, struct uhci_qh *qh,
1378                 struct urb *urb)
1379 __releases(uhci->lock)
1380 __acquires(uhci->lock)
1381 {
1382         struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;
1383
1384         /* When giving back the first URB in an Isochronous queue,
1385          * reinitialize the QH's iso-related members for the next URB. */
1386         if (qh->type == USB_ENDPOINT_XFER_ISOC &&
1387                         urbp->node.prev == &qh->queue &&
1388                         urbp->node.next != &qh->queue) {
1389                 struct urb *nurb = list_entry(urbp->node.next,
1390                                 struct urb_priv, node)->urb;
1391
1392                 qh->iso_packet_desc = &nurb->iso_frame_desc[0];
1393                 qh->iso_frame = nurb->start_frame;
1394                 qh->iso_status = 0;
1395         }
1396
1397         /* Take the URB off the QH's queue.  If the queue is now empty,
1398          * this is a perfect time for a toggle fixup. */
1399         list_del_init(&urbp->node);
1400         if (list_empty(&qh->queue) && qh->needs_fixup) {
1401                 usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
1402                                 usb_pipeout(urb->pipe), qh->initial_toggle);
1403                 qh->needs_fixup = 0;
1404         }
1405
1406         uhci_free_urb_priv(uhci, urbp);
1407
1408         spin_unlock(&uhci->lock);
1409         usb_hcd_giveback_urb(uhci_to_hcd(uhci), urb);
1410         spin_lock(&uhci->lock);
1411
1412         /* If the queue is now empty, we can unlink the QH and give up its
1413          * reserved bandwidth. */
1414         if (list_empty(&qh->queue)) {
1415                 uhci_unlink_qh(uhci, qh);
1416                 if (qh->bandwidth_reserved)
1417                         uhci_release_bandwidth(uhci, qh);
1418         }
1419 }
1420
1421 /*
1422  * Scan the URBs in a QH's queue
1423  */
1424 #define QH_FINISHED_UNLINKING(qh)                       \
1425                 (qh->state == QH_STATE_UNLINKING &&     \
1426                 uhci->frame_number + uhci->is_stopped != qh->unlink_frame)
1427
1428 static void uhci_scan_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
1429 {
1430         struct urb_priv *urbp;
1431         struct urb *urb;
1432         int status;
1433
1434         while (!list_empty(&qh->queue)) {
1435                 urbp = list_entry(qh->queue.next, struct urb_priv, node);
1436                 urb = urbp->urb;
1437
1438                 if (qh->type == USB_ENDPOINT_XFER_ISOC)
1439                         status = uhci_result_isochronous(uhci, urb);
1440                 else
1441                         status = uhci_result_common(uhci, urb);
1442                 if (status == -EINPROGRESS)
1443                         break;
1444
1445                 spin_lock(&urb->lock);
1446                 if (urb->status == -EINPROGRESS)        /* Not dequeued */
1447                         urb->status = status;
1448                 else
1449                         status = ECONNRESET;            /* Not -ECONNRESET */
1450                 spin_unlock(&urb->lock);
1451
1452                 /* Dequeued but completed URBs can't be given back unless
1453                  * the QH is stopped or has finished unlinking. */
1454                 if (status == ECONNRESET) {
1455                         if (QH_FINISHED_UNLINKING(qh))
1456                                 qh->is_stopped = 1;
1457                         else if (!qh->is_stopped)
1458                                 return;
1459                 }
1460
1461                 uhci_giveback_urb(uhci, qh, urb);
1462                 if (status < 0 && qh->type != USB_ENDPOINT_XFER_ISOC)
1463                         break;
1464         }
1465
1466         /* If the QH is neither stopped nor finished unlinking (normal case),
1467          * our work here is done. */
1468         if (QH_FINISHED_UNLINKING(qh))
1469                 qh->is_stopped = 1;
1470         else if (!qh->is_stopped)
1471                 return;
1472
1473         /* Otherwise give back each of the dequeued URBs */
1474 restart:
1475         list_for_each_entry(urbp, &qh->queue, node) {
1476                 urb = urbp->urb;
1477                 if (urb->status != -EINPROGRESS) {
1478
1479                         /* Fix up the TD links and save the toggles for
1480                          * non-Isochronous queues.  For Isochronous queues,
1481                          * test for too-recent dequeues. */
1482                         if (!uhci_cleanup_queue(uhci, qh, urb)) {
1483                                 qh->is_stopped = 0;
1484                                 return;
1485                         }
1486                         uhci_giveback_urb(uhci, qh, urb);
1487                         goto restart;
1488                 }
1489         }
1490         qh->is_stopped = 0;
1491
1492         /* There are no more dequeued URBs.  If there are still URBs on the
1493          * queue, the QH can now be re-activated. */
1494         if (!list_empty(&qh->queue)) {
1495                 if (qh->needs_fixup)
1496                         uhci_fixup_toggles(qh, 0);
1497
1498                 /* If the first URB on the queue wants FSBR but its time
1499                  * limit has expired, set the next TD to interrupt on
1500                  * completion before reactivating the QH. */
1501                 urbp = list_entry(qh->queue.next, struct urb_priv, node);
1502                 if (urbp->fsbr && qh->wait_expired) {
1503                         struct uhci_td *td = list_entry(urbp->td_list.next,
1504                                         struct uhci_td, list);
1505
1506                         td->status |= __cpu_to_le32(TD_CTRL_IOC);
1507                 }
1508
1509                 uhci_activate_qh(uhci, qh);
1510         }
1511
1512         /* The queue is empty.  The QH can become idle if it is fully
1513          * unlinked. */
1514         else if (QH_FINISHED_UNLINKING(qh))
1515                 uhci_make_qh_idle(uhci, qh);
1516 }
1517
1518 /*
1519  * Check for queues that have made some forward progress.
1520  * Returns 0 if the queue is not Isochronous, is ACTIVE, and
1521  * has not advanced since last examined; 1 otherwise.
1522  *
1523  * Early Intel controllers have a bug which causes qh->element sometimes
1524  * not to advance when a TD completes successfully.  The queue remains
1525  * stuck on the inactive completed TD.  We detect such cases and advance
1526  * the element pointer by hand.
1527  */
1528 static int uhci_advance_check(struct uhci_hcd *uhci, struct uhci_qh *qh)
1529 {
1530         struct urb_priv *urbp = NULL;
1531         struct uhci_td *td;
1532         int ret = 1;
1533         unsigned status;
1534
1535         if (qh->type == USB_ENDPOINT_XFER_ISOC)
1536                 goto done;
1537
1538         /* Treat an UNLINKING queue as though it hasn't advanced.
1539          * This is okay because reactivation will treat it as though
1540          * it has advanced, and if it is going to become IDLE then
1541          * this doesn't matter anyway.  Furthermore it's possible
1542          * for an UNLINKING queue not to have any URBs at all, or
1543          * for its first URB not to have any TDs (if it was dequeued
1544          * just as it completed).  So it's not easy in any case to
1545          * test whether such queues have advanced. */
1546         if (qh->state != QH_STATE_ACTIVE) {
1547                 urbp = NULL;
1548                 status = 0;
1549
1550         } else {
1551                 urbp = list_entry(qh->queue.next, struct urb_priv, node);
1552                 td = list_entry(urbp->td_list.next, struct uhci_td, list);
1553                 status = td_status(td);
1554                 if (!(status & TD_CTRL_ACTIVE)) {
1555
1556                         /* We're okay, the queue has advanced */
1557                         qh->wait_expired = 0;
1558                         qh->advance_jiffies = jiffies;
1559                         goto done;
1560                 }
1561                 ret = 0;
1562         }
1563
1564         /* The queue hasn't advanced; check for timeout */
1565         if (qh->wait_expired)
1566                 goto done;
1567
1568         if (time_after(jiffies, qh->advance_jiffies + QH_WAIT_TIMEOUT)) {
1569
1570                 /* Detect the Intel bug and work around it */
1571                 if (qh->post_td && qh_element(qh) ==
1572                                 cpu_to_le32(qh->post_td->dma_handle)) {
1573                         qh->element = qh->post_td->link;
1574                         qh->advance_jiffies = jiffies;
1575                         ret = 1;
1576                         goto done;
1577                 }
1578
1579                 qh->wait_expired = 1;
1580
1581                 /* If the current URB wants FSBR, unlink it temporarily
1582                  * so that we can safely set the next TD to interrupt on
1583                  * completion.  That way we'll know as soon as the queue
1584                  * starts moving again. */
1585                 if (urbp && urbp->fsbr && !(status & TD_CTRL_IOC))
1586                         uhci_unlink_qh(uhci, qh);
1587
1588         } else {
1589                 /* Unmoving but not-yet-expired queues keep FSBR alive */
1590                 if (urbp)
1591                         uhci_urbp_wants_fsbr(uhci, urbp);
1592         }
1593
1594 done:
1595         return ret;
1596 }
1597
1598 /*
1599  * Process events in the schedule, but only in one thread at a time
1600  */
1601 static void uhci_scan_schedule(struct uhci_hcd *uhci)
1602 {
1603         int i;
1604         struct uhci_qh *qh;
1605
1606         /* Don't allow re-entrant calls */
1607         if (uhci->scan_in_progress) {
1608                 uhci->need_rescan = 1;
1609                 return;
1610         }
1611         uhci->scan_in_progress = 1;
1612 rescan:
1613         uhci->need_rescan = 0;
1614         uhci->fsbr_is_wanted = 0;
1615
1616         uhci_clear_next_interrupt(uhci);
1617         uhci_get_current_frame_number(uhci);
1618         uhci->cur_iso_frame = uhci->frame_number;
1619
1620         /* Go through all the QH queues and process the URBs in each one */
1621         for (i = 0; i < UHCI_NUM_SKELQH - 1; ++i) {
1622                 uhci->next_qh = list_entry(uhci->skelqh[i]->node.next,
1623                                 struct uhci_qh, node);
1624                 while ((qh = uhci->next_qh) != uhci->skelqh[i]) {
1625                         uhci->next_qh = list_entry(qh->node.next,
1626                                         struct uhci_qh, node);
1627
1628                         if (uhci_advance_check(uhci, qh)) {
1629                                 uhci_scan_qh(uhci, qh);
1630                                 if (qh->state == QH_STATE_ACTIVE) {
1631                                         uhci_urbp_wants_fsbr(uhci,
1632         list_entry(qh->queue.next, struct urb_priv, node));
1633                                 }
1634                         }
1635                 }
1636         }
1637
1638         uhci->last_iso_frame = uhci->cur_iso_frame;
1639         if (uhci->need_rescan)
1640                 goto rescan;
1641         uhci->scan_in_progress = 0;
1642
1643         if (uhci->fsbr_is_on && !uhci->fsbr_is_wanted &&
1644                         !uhci->fsbr_expiring) {
1645                 uhci->fsbr_expiring = 1;
1646                 mod_timer(&uhci->fsbr_timer, jiffies + FSBR_OFF_DELAY);
1647         }
1648
1649         if (list_empty(&uhci->skel_unlink_qh->node))
1650                 uhci_clear_next_interrupt(uhci);
1651         else
1652                 uhci_set_next_interrupt(uhci);
1653 }