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 }