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 2004-2005 Alan Stern, stern@rowland.harvard.edu
  17  */
  18
  19 static void uhci_free_pending_tds(struct uhci_hcd *uhci);
  20
  21 /*
  22  * Technically, updating td->status here is a race, but it's not really a
  23  * problem. The worst that can happen is that we set the IOC bit again
  24  * generating a spurious interrupt. We could fix this by creating another
  25  * QH and leaving the IOC bit always set, but then we would have to play
  26  * games with the FSBR code to make sure we get the correct order in all
  27  * the cases. I don't think it's worth the effort
  28  */
  29 static void uhci_set_next_interrupt(struct uhci_hcd *uhci)
  30 {
  31         if (uhci->is_stopped)
  32                 mod_timer(&uhci_to_hcd(uhci)->rh_timer, jiffies);
  33         uhci->term_td->status |= cpu_to_le32(TD_CTRL_IOC);
  34 }
  35
  36 static inline void uhci_clear_next_interrupt(struct uhci_hcd *uhci)
  37 {
  38         uhci->term_td->status &= ~cpu_to_le32(TD_CTRL_IOC);
  39 }
  40
  41 static struct uhci_td *uhci_alloc_td(struct uhci_hcd *uhci)
  42 {
  43         dma_addr_t dma_handle;
  44         struct uhci_td *td;
  45
  46         td = dma_pool_alloc(uhci->td_pool, GFP_ATOMIC, &dma_handle);
  47         if (!td)
  48                 return NULL;
  49
  50         td->dma_handle = dma_handle;
  51         td->frame = -1;
  52
  53         INIT_LIST_HEAD(&td->list);
  54         INIT_LIST_HEAD(&td->remove_list);
  55         INIT_LIST_HEAD(&td->fl_list);
  56
  57         return td;
  58 }
  59
  60 static void uhci_free_td(struct uhci_hcd *uhci, struct uhci_td *td)
  61 {
  62         if (!list_empty(&td->list))
  63                 dev_warn(uhci_dev(uhci), "td %p still in list!\n", td);
  64         if (!list_empty(&td->remove_list))
  65                 dev_warn(uhci_dev(uhci), "td %p still in remove_list!\n", td);
  66         if (!list_empty(&td->fl_list))
  67                 dev_warn(uhci_dev(uhci), "td %p still in fl_list!\n", td);
  68
  69         dma_pool_free(uhci->td_pool, td, td->dma_handle);
  70 }
  71
  72 static inline void uhci_fill_td(struct uhci_td *td, u32 status,
  73                 u32 token, u32 buffer)
  74 {
  75         td->status = cpu_to_le32(status);
  76         td->token = cpu_to_le32(token);
  77         td->buffer = cpu_to_le32(buffer);
  78 }
  79
  80 /*
  81  * We insert Isochronous URBs directly into the frame list at the beginning
  82  */
  83 static inline void uhci_insert_td_in_frame_list(struct uhci_hcd *uhci,
  84                 struct uhci_td *td, unsigned framenum)
  85 {
  86         framenum &= (UHCI_NUMFRAMES - 1);
  87
  88         td->frame = framenum;
  89
  90         /* Is there a TD already mapped there? */
  91         if (uhci->frame_cpu[framenum]) {
  92                 struct uhci_td *ftd, *ltd;
  93
  94                 ftd = uhci->frame_cpu[framenum];
  95                 ltd = list_entry(ftd->fl_list.prev, struct uhci_td, fl_list);
  96
  97                 list_add_tail(&td->fl_list, &ftd->fl_list);
  98
  99                 td->link = ltd->link;
 100                 wmb();
 101                 ltd->link = cpu_to_le32(td->dma_handle);
 102         } else {
 103                 td->link = uhci->frame[framenum];
 104                 wmb();
 105                 uhci->frame[framenum] = cpu_to_le32(td->dma_handle);
 106                 uhci->frame_cpu[framenum] = td;
 107         }
 108 }
 109
 110 static inline void uhci_remove_td_from_frame_list(struct uhci_hcd *uhci,
 111                 struct uhci_td *td)
 112 {
 113         /* If it's not inserted, don't remove it */
 114         if (td->frame == -1) {
 115                 WARN_ON(!list_empty(&td->fl_list));
 116                 return;
 117         }
 118
 119         if (uhci->frame_cpu[td->frame] == td) {
 120                 if (list_empty(&td->fl_list)) {
 121                         uhci->frame[td->frame] = td->link;
 122                         uhci->frame_cpu[td->frame] = NULL;
 123                 } else {
 124                         struct uhci_td *ntd;
 125
 126                         ntd = list_entry(td->fl_list.next, struct uhci_td, fl_list);
 127                         uhci->frame[td->frame] = cpu_to_le32(ntd->dma_handle);
 128                         uhci->frame_cpu[td->frame] = ntd;
 129                 }
 130         } else {
 131                 struct uhci_td *ptd;
 132
 133                 ptd = list_entry(td->fl_list.prev, struct uhci_td, fl_list);
 134                 ptd->link = td->link;
 135         }
 136
 137         list_del_init(&td->fl_list);
 138         td->frame = -1;
 139 }
 140
 141 /*
 142  * Remove all the TDs for an Isochronous URB from the frame list
 143  */
 144 static void uhci_unlink_isochronous_tds(struct uhci_hcd *uhci, struct urb *urb)
 145 {
 146         struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;
 147         struct uhci_td *td;
 148
 149         list_for_each_entry(td, &urbp->td_list, list)
 150                 uhci_remove_td_from_frame_list(uhci, td);
 151         wmb();
 152 }
 153
 154 static struct uhci_qh *uhci_alloc_qh(struct uhci_hcd *uhci,
 155                 struct usb_device *udev, struct usb_host_endpoint *hep)
 156 {
 157         dma_addr_t dma_handle;
 158         struct uhci_qh *qh;
 159
 160         qh = dma_pool_alloc(uhci->qh_pool, GFP_ATOMIC, &dma_handle);
 161         if (!qh)
 162                 return NULL;
 163
 164         qh->dma_handle = dma_handle;
 165
 166         qh->element = UHCI_PTR_TERM;
 167         qh->link = UHCI_PTR_TERM;
 168
 169         INIT_LIST_HEAD(&qh->queue);
 170         INIT_LIST_HEAD(&qh->node);
 171
 172         if (udev) {             /* Normal QH */
 173                 qh->dummy_td = uhci_alloc_td(uhci);
 174                 if (!qh->dummy_td) {
 175                         dma_pool_free(uhci->qh_pool, qh, dma_handle);
 176                         return NULL;
 177                 }
 178                 qh->state = QH_STATE_IDLE;
 179                 qh->hep = hep;
 180                 qh->udev = udev;
 181                 hep->hcpriv = qh;
 182                 qh->type = hep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
 183
 184         } else {                /* Skeleton QH */
 185                 qh->state = QH_STATE_ACTIVE;
 186                 qh->udev = NULL;
 187                 qh->type = -1;
 188         }
 189         return qh;
 190 }
 191
 192 static void uhci_free_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
 193 {
 194         WARN_ON(qh->state != QH_STATE_IDLE && qh->udev);
 195         if (!list_empty(&qh->queue))
 196                 dev_warn(uhci_dev(uhci), "qh %p list not empty!\n", qh);
 197
 198         list_del(&qh->node);
 199         if (qh->udev) {
 200                 qh->hep->hcpriv = NULL;
 201                 uhci_free_td(uhci, qh->dummy_td);
 202         }
 203         dma_pool_free(uhci->qh_pool, qh, qh->dma_handle);
 204 }
 205
 206 /*
 207  * When the currently executing URB is dequeued, save its current toggle value
 208  */
 209 static void uhci_save_toggle(struct uhci_qh *qh, struct urb *urb)
 210 {
 211         struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;
 212         struct uhci_td *td;
 213
 214         /* If the QH element pointer is UHCI_PTR_TERM then then currently
 215          * executing URB has already been unlinked, so this one isn't it. */
 216         if (qh_element(qh) == UHCI_PTR_TERM ||
 217                                 qh->queue.next != &urbp->node)
 218                 return;
 219         qh->element = UHCI_PTR_TERM;
 220
 221         /* Only bulk and interrupt pipes have to worry about toggles */
 222         if (!(qh->type == USB_ENDPOINT_XFER_BULK ||
 223                         qh->type == USB_ENDPOINT_XFER_INT))
 224                 return;
 225
 226         /* Find the first active TD; that's the device's toggle state */
 227         list_for_each_entry(td, &urbp->td_list, list) {
 228                 if (td_status(td) & TD_CTRL_ACTIVE) {
 229                         qh->needs_fixup = 1;
 230                         qh->initial_toggle = uhci_toggle(td_token(td));
 231                         return;
 232                 }
 233         }
 234
 235         WARN_ON(1);
 236 }
 237
 238 /*
 239  * Fix up the data toggles for URBs in a queue, when one of them
 240  * terminates early (short transfer, error, or dequeued).
 241  */
 242 static void uhci_fixup_toggles(struct uhci_qh *qh, int skip_first)
 243 {
 244         struct urb_priv *urbp = NULL;
 245         struct uhci_td *td;
 246         unsigned int toggle = qh->initial_toggle;
 247         unsigned int pipe;
 248
 249         /* Fixups for a short transfer start with the second URB in the
 250          * queue (the short URB is the first). */
 251         if (skip_first)
 252                 urbp = list_entry(qh->queue.next, struct urb_priv, node);
 253
 254         /* When starting with the first URB, if the QH element pointer is
 255          * still valid then we know the URB's toggles are okay. */
 256         else if (qh_element(qh) != UHCI_PTR_TERM)
 257                 toggle = 2;
 258
 259         /* Fix up the toggle for the URBs in the queue.  Normally this
 260          * loop won't run more than once: When an error or short transfer
 261          * occurs, the queue usually gets emptied. */
 262         urbp = list_prepare_entry(urbp, &qh->queue, node);
 263         list_for_each_entry_continue(urbp, &qh->queue, node) {
 264
 265                 /* If the first TD has the right toggle value, we don't
 266                  * need to change any toggles in this URB */
 267                 td = list_entry(urbp->td_list.next, struct uhci_td, list);
 268                 if (toggle > 1 || uhci_toggle(td_token(td)) == toggle) {
 269                         td = list_entry(urbp->td_list.next, struct uhci_td,
 270                                         list);
 271                         toggle = uhci_toggle(td_token(td)) ^ 1;
 272
 273                 /* Otherwise all the toggles in the URB have to be switched */
 274                 } else {
 275                         list_for_each_entry(td, &urbp->td_list, list) {
 276                                 td->token ^= __constant_cpu_to_le32(
 277                                                         TD_TOKEN_TOGGLE);
 278                                 toggle ^= 1;
 279                         }
 280                 }
 281         }
 282
 283         wmb();
 284         pipe = list_entry(qh->queue.next, struct urb_priv, node)->urb->pipe;
 285         usb_settoggle(qh->udev, usb_pipeendpoint(pipe),
 286                         usb_pipeout(pipe), toggle);
 287         qh->needs_fixup = 0;
 288 }
 289
 290 /*
 291  * Put a QH on the schedule in both hardware and software
 292  */
 293 static void uhci_activate_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
 294 {
 295         struct uhci_qh *pqh;
 296
 297         WARN_ON(list_empty(&qh->queue));
 298
 299         /* Set the element pointer if it isn't set already.
 300          * This isn't needed for Isochronous queues, but it doesn't hurt. */
 301         if (qh_element(qh) == UHCI_PTR_TERM) {
 302                 struct urb_priv *urbp = list_entry(qh->queue.next,
 303                                 struct urb_priv, node);
 304                 struct uhci_td *td = list_entry(urbp->td_list.next,
 305                                 struct uhci_td, list);
 306
 307                 qh->element = cpu_to_le32(td->dma_handle);
 308         }
 309
 310         if (qh->state == QH_STATE_ACTIVE)
 311                 return;
 312         qh->state = QH_STATE_ACTIVE;
 313
 314         /* Move the QH from its old list to the end of the appropriate
 315          * skeleton's list */
 316         if (qh == uhci->next_qh)
 317                 uhci->next_qh = list_entry(qh->node.next, struct uhci_qh,
 318                                 node);
 319         list_move_tail(&qh->node, &qh->skel->node);
 320
 321         /* Link it into the schedule */
 322         pqh = list_entry(qh->node.prev, struct uhci_qh, node);
 323         qh->link = pqh->link;
 324         wmb();
 325         pqh->link = UHCI_PTR_QH | cpu_to_le32(qh->dma_handle);
 326 }
 327
 328 /*
 329  * Take a QH off the hardware schedule
 330  */
 331 static void uhci_unlink_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
 332 {
 333         struct uhci_qh *pqh;
 334
 335         if (qh->state == QH_STATE_UNLINKING)
 336                 return;
 337         WARN_ON(qh->state != QH_STATE_ACTIVE || !qh->udev);
 338         qh->state = QH_STATE_UNLINKING;
 339
 340         /* Unlink the QH from the schedule and record when we did it */
 341         pqh = list_entry(qh->node.prev, struct uhci_qh, node);
 342         pqh->link = qh->link;
 343         mb();
 344
 345         uhci_get_current_frame_number(uhci);
 346         qh->unlink_frame = uhci->frame_number;
 347
 348         /* Force an interrupt so we know when the QH is fully unlinked */
 349         if (list_empty(&uhci->skel_unlink_qh->node))
 350                 uhci_set_next_interrupt(uhci);
 351
 352         /* Move the QH from its old list to the end of the unlinking list */
 353         if (qh == uhci->next_qh)
 354                 uhci->next_qh = list_entry(qh->node.next, struct uhci_qh,
 355                                 node);
 356         list_move_tail(&qh->node, &uhci->skel_unlink_qh->node);
 357 }
 358
 359 /*
 360  * When we and the controller are through with a QH, it becomes IDLE.
 361  * This happens when a QH has been off the schedule (on the unlinking
 362  * list) for more than one frame, or when an error occurs while adding
 363  * the first URB onto a new QH.
 364  */
 365 static void uhci_make_qh_idle(struct uhci_hcd *uhci, struct uhci_qh *qh)
 366 {
 367         WARN_ON(qh->state == QH_STATE_ACTIVE);
 368
 369         if (qh == uhci->next_qh)
 370                 uhci->next_qh = list_entry(qh->node.next, struct uhci_qh,
 371                                 node);
 372         list_move(&qh->node, &uhci->idle_qh_list);
 373         qh->state = QH_STATE_IDLE;
 374
 375         /* If anyone is waiting for a QH to become idle, wake them up */
 376         if (uhci->num_waiting)
 377                 wake_up_all(&uhci->waitqh);
 378 }
 379
 380 static inline struct urb_priv *uhci_alloc_urb_priv(struct uhci_hcd *uhci,
 381                 struct urb *urb)
 382 {
 383         struct urb_priv *urbp;
 384
 385         urbp = kmem_cache_alloc(uhci_up_cachep, SLAB_ATOMIC);
 386         if (!urbp)
 387                 return NULL;
 388
 389         memset((void *)urbp, 0, sizeof(*urbp));
 390
 391         urbp->urb = urb;
 392         urb->hcpriv = urbp;
 393
 394         INIT_LIST_HEAD(&urbp->node);
 395         INIT_LIST_HEAD(&urbp->td_list);
 396
 397         return urbp;
 398 }
 399
 400 static void uhci_add_td_to_urb(struct urb *urb, struct uhci_td *td)
 401 {
 402         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 403
 404         list_add_tail(&td->list, &urbp->td_list);
 405 }
 406
 407 static void uhci_remove_td_from_urb(struct uhci_td *td)
 408 {
 409         if (list_empty(&td->list))
 410                 return;
 411
 412         list_del_init(&td->list);
 413 }
 414
 415 static void uhci_free_urb_priv(struct uhci_hcd *uhci,
 416                 struct urb_priv *urbp)
 417 {
 418         struct uhci_td *td, *tmp;
 419
 420         if (!list_empty(&urbp->node))
 421                 dev_warn(uhci_dev(uhci), "urb %p still on QH's list!\n",
 422                                 urbp->urb);
 423
 424         uhci_get_current_frame_number(uhci);
 425         if (uhci->frame_number + uhci->is_stopped != uhci->td_remove_age) {
 426                 uhci_free_pending_tds(uhci);
 427                 uhci->td_remove_age = uhci->frame_number;
 428         }
 429
 430         /* Check to see if the remove list is empty. Set the IOC bit */
 431         /* to force an interrupt so we can remove the TDs. */
 432         if (list_empty(&uhci->td_remove_list))
 433                 uhci_set_next_interrupt(uhci);
 434
 435         list_for_each_entry_safe(td, tmp, &urbp->td_list, list) {
 436                 uhci_remove_td_from_urb(td);
 437                 list_add(&td->remove_list, &uhci->td_remove_list);
 438         }
 439
 440         urbp->urb->hcpriv = NULL;
 441         kmem_cache_free(uhci_up_cachep, urbp);
 442 }
 443
 444 static void uhci_inc_fsbr(struct uhci_hcd *uhci, struct urb *urb)
 445 {
 446         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 447
 448         if ((!(urb->transfer_flags & URB_NO_FSBR)) && !urbp->fsbr) {
 449                 urbp->fsbr = 1;
 450                 if (!uhci->fsbr++ && !uhci->fsbrtimeout)
 451                         uhci->skel_term_qh->link = cpu_to_le32(uhci->skel_fs_control_qh->dma_handle) | UHCI_PTR_QH;
 452         }
 453 }
 454
 455 static void uhci_dec_fsbr(struct uhci_hcd *uhci, struct urb *urb)
 456 {
 457         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 458
 459         if ((!(urb->transfer_flags & URB_NO_FSBR)) && urbp->fsbr) {
 460                 urbp->fsbr = 0;
 461                 if (!--uhci->fsbr)
 462                         uhci->fsbrtimeout = jiffies + FSBR_DELAY;
 463         }
 464 }
 465
 466 /*
 467  * Map status to standard result codes
 468  *
 469  * <status> is (td_status(td) & 0xF60000), a.k.a.
 470  * uhci_status_bits(td_status(td)).
 471  * Note: <status> does not include the TD_CTRL_NAK bit.
 472  * <dir_out> is True for output TDs and False for input TDs.
 473  */
 474 static int uhci_map_status(int status, int dir_out)
 475 {
 476         if (!status)
 477                 return 0;
 478         if (status & TD_CTRL_BITSTUFF)                  /* Bitstuff error */
 479                 return -EPROTO;
 480         if (status & TD_CTRL_CRCTIMEO) {                /* CRC/Timeout */
 481                 if (dir_out)
 482                         return -EPROTO;
 483                 else
 484                         return -EILSEQ;
 485         }
 486         if (status & TD_CTRL_BABBLE)                    /* Babble */
 487                 return -EOVERFLOW;
 488         if (status & TD_CTRL_DBUFERR)                   /* Buffer error */
 489                 return -ENOSR;
 490         if (status & TD_CTRL_STALLED)                   /* Stalled */
 491                 return -EPIPE;
 492         WARN_ON(status & TD_CTRL_ACTIVE);               /* Active */
 493         return 0;
 494 }
 495
 496 /*
 497  * Control transfers
 498  */
 499 static int uhci_submit_control(struct uhci_hcd *uhci, struct urb *urb,
 500                 struct uhci_qh *qh)
 501 {
 502         struct uhci_td *td;
 503         unsigned long destination, status;
 504         int maxsze = le16_to_cpu(qh->hep->desc.wMaxPacketSize);
 505         int len = urb->transfer_buffer_length;
 506         dma_addr_t data = urb->transfer_dma;
 507         __le32 *plink;
 508
 509         /* The "pipe" thing contains the destination in bits 8--18 */
 510         destination = (urb->pipe & PIPE_DEVEP_MASK) | USB_PID_SETUP;
 511
 512         /* 3 errors, dummy TD remains inactive */
 513         status = uhci_maxerr(3);
 514         if (urb->dev->speed == USB_SPEED_LOW)
 515                 status |= TD_CTRL_LS;
 516
 517         /*
 518          * Build the TD for the control request setup packet
 519          */
 520         td = qh->dummy_td;
 521         uhci_add_td_to_urb(urb, td);
 522         uhci_fill_td(td, status, destination | uhci_explen(8),
 523                         urb->setup_dma);
 524         plink = &td->link;
 525         status |= TD_CTRL_ACTIVE;
 526
 527         /*
 528          * If direction is "send", change the packet ID from SETUP (0x2D)
 529          * to OUT (0xE1).  Else change it from SETUP to IN (0x69) and
 530          * set Short Packet Detect (SPD) for all data packets.
 531          */
 532         if (usb_pipeout(urb->pipe))
 533                 destination ^= (USB_PID_SETUP ^ USB_PID_OUT);
 534         else {
 535                 destination ^= (USB_PID_SETUP ^ USB_PID_IN);
 536                 status |= TD_CTRL_SPD;
 537         }
 538
 539         /*
 540          * Build the DATA TDs
 541          */
 542         while (len > 0) {
 543                 int pktsze = min(len, maxsze);
 544
 545                 td = uhci_alloc_td(uhci);
 546                 if (!td)
 547                         goto nomem;
 548                 *plink = cpu_to_le32(td->dma_handle);
 549
 550                 /* Alternate Data0/1 (start with Data1) */
 551                 destination ^= TD_TOKEN_TOGGLE;
 552
 553                 uhci_add_td_to_urb(urb, td);
 554                 uhci_fill_td(td, status, destination | uhci_explen(pktsze),
 555                                 data);
 556                 plink = &td->link;
 557
 558                 data += pktsze;
 559                 len -= pktsze;
 560         }
 561
 562         /*
 563          * Build the final TD for control status
 564          */
 565         td = uhci_alloc_td(uhci);
 566         if (!td)
 567                 goto nomem;
 568         *plink = cpu_to_le32(td->dma_handle);
 569
 570         /*
 571          * It's IN if the pipe is an output pipe or we're not expecting
 572          * data back.
 573          */
 574         destination &= ~TD_TOKEN_PID_MASK;
 575         if (usb_pipeout(urb->pipe) || !urb->transfer_buffer_length)
 576                 destination |= USB_PID_IN;
 577         else
 578                 destination |= USB_PID_OUT;
 579
 580         destination |= TD_TOKEN_TOGGLE;         /* End in Data1 */
 581
 582         status &= ~TD_CTRL_SPD;
 583
 584         uhci_add_td_to_urb(urb, td);
 585         uhci_fill_td(td, status | TD_CTRL_IOC,
 586                         destination | uhci_explen(0), 0);
 587         plink = &td->link;
 588
 589         /*
 590          * Build the new dummy TD and activate the old one
 591          */
 592         td = uhci_alloc_td(uhci);
 593         if (!td)
 594                 goto nomem;
 595         *plink = cpu_to_le32(td->dma_handle);
 596
 597         uhci_fill_td(td, 0, USB_PID_OUT | uhci_explen(0), 0);
 598         wmb();
 599         qh->dummy_td->status |= __constant_cpu_to_le32(TD_CTRL_ACTIVE);
 600         qh->dummy_td = td;
 601
 602         /* Low-speed transfers get a different queue, and won't hog the bus.
 603          * Also, some devices enumerate better without FSBR; the easiest way
 604          * to do that is to put URBs on the low-speed queue while the device
 605          * isn't in the CONFIGURED state. */
 606         if (urb->dev->speed == USB_SPEED_LOW ||
 607                         urb->dev->state != USB_STATE_CONFIGURED)
 608                 qh->skel = uhci->skel_ls_control_qh;
 609         else {
 610                 qh->skel = uhci->skel_fs_control_qh;
 611                 uhci_inc_fsbr(uhci, urb);
 612         }
 613         return 0;
 614
 615 nomem:
 616         /* Remove the dummy TD from the td_list so it doesn't get freed */
 617         uhci_remove_td_from_urb(qh->dummy_td);
 618         return -ENOMEM;
 619 }
 620
 621 /*
 622  * Common submit for bulk and interrupt
 623  */
 624 static int uhci_submit_common(struct uhci_hcd *uhci, struct urb *urb,
 625                 struct uhci_qh *qh)
 626 {
 627         struct uhci_td *td;
 628         unsigned long destination, status;
 629         int maxsze = le16_to_cpu(qh->hep->desc.wMaxPacketSize);
 630         int len = urb->transfer_buffer_length;
 631         dma_addr_t data = urb->transfer_dma;
 632         __le32 *plink;
 633         unsigned int toggle;
 634
 635         if (len < 0)
 636                 return -EINVAL;
 637
 638         /* The "pipe" thing contains the destination in bits 8--18 */
 639         destination = (urb->pipe & PIPE_DEVEP_MASK) | usb_packetid(urb->pipe);
 640         toggle = usb_gettoggle(urb->dev, usb_pipeendpoint(urb->pipe),
 641                          usb_pipeout(urb->pipe));
 642
 643         /* 3 errors, dummy TD remains inactive */
 644         status = uhci_maxerr(3);
 645         if (urb->dev->speed == USB_SPEED_LOW)
 646                 status |= TD_CTRL_LS;
 647         if (usb_pipein(urb->pipe))
 648                 status |= TD_CTRL_SPD;
 649
 650         /*
 651          * Build the DATA TDs
 652          */
 653         plink = NULL;
 654         td = qh->dummy_td;
 655         do {    /* Allow zero length packets */
 656                 int pktsze = maxsze;
 657
 658                 if (len <= pktsze) {            /* The last packet */
 659                         pktsze = len;
 660                         if (!(urb->transfer_flags & URB_SHORT_NOT_OK))
 661                                 status &= ~TD_CTRL_SPD;
 662                 }
 663
 664                 if (plink) {
 665                         td = uhci_alloc_td(uhci);
 666                         if (!td)
 667                                 goto nomem;
 668                         *plink = cpu_to_le32(td->dma_handle);
 669                 }
 670                 uhci_add_td_to_urb(urb, td);
 671                 uhci_fill_td(td, status,
 672                                 destination | uhci_explen(pktsze) |
 673                                         (toggle << TD_TOKEN_TOGGLE_SHIFT),
 674                                 data);
 675                 plink = &td->link;
 676                 status |= TD_CTRL_ACTIVE;
 677
 678                 data += pktsze;
 679                 len -= maxsze;
 680                 toggle ^= 1;
 681         } while (len > 0);
 682
 683         /*
 684          * URB_ZERO_PACKET means adding a 0-length packet, if direction
 685          * is OUT and the transfer_length was an exact multiple of maxsze,
 686          * hence (len = transfer_length - N * maxsze) == 0
 687          * however, if transfer_length == 0, the zero packet was already
 688          * prepared above.
 689          */
 690         if ((urb->transfer_flags & URB_ZERO_PACKET) &&
 691                         usb_pipeout(urb->pipe) && len == 0 &&
 692                         urb->transfer_buffer_length > 0) {
 693                 td = uhci_alloc_td(uhci);
 694                 if (!td)
 695                         goto nomem;
 696                 *plink = cpu_to_le32(td->dma_handle);
 697
 698                 uhci_add_td_to_urb(urb, td);
 699                 uhci_fill_td(td, status,
 700                                 destination | uhci_explen(0) |
 701                                         (toggle << TD_TOKEN_TOGGLE_SHIFT),
 702                                 data);
 703                 plink = &td->link;
 704
 705                 toggle ^= 1;
 706         }
 707
 708         /* Set the interrupt-on-completion flag on the last packet.
 709          * A more-or-less typical 4 KB URB (= size of one memory page)
 710          * will require about 3 ms to transfer; that's a little on the
 711          * fast side but not enough to justify delaying an interrupt
 712          * more than 2 or 3 URBs, so we will ignore the URB_NO_INTERRUPT
 713          * flag setting. */
 714         td->status |= __constant_cpu_to_le32(TD_CTRL_IOC);
 715
 716         /*
 717          * Build the new dummy TD and activate the old one
 718          */
 719         td = uhci_alloc_td(uhci);
 720         if (!td)
 721                 goto nomem;
 722         *plink = cpu_to_le32(td->dma_handle);
 723
 724         uhci_fill_td(td, 0, USB_PID_OUT | uhci_explen(0), 0);
 725         wmb();
 726         qh->dummy_td->status |= __constant_cpu_to_le32(TD_CTRL_ACTIVE);
 727         qh->dummy_td = td;
 728
 729         usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
 730                         usb_pipeout(urb->pipe), toggle);
 731         return 0;
 732
 733 nomem:
 734         /* Remove the dummy TD from the td_list so it doesn't get freed */
 735         uhci_remove_td_from_urb(qh->dummy_td);
 736         return -ENOMEM;
 737 }
 738
 739 static inline int uhci_submit_bulk(struct uhci_hcd *uhci, struct urb *urb,
 740                 struct uhci_qh *qh)
 741 {
 742         int ret;
 743
 744         /* Can't have low-speed bulk transfers */
 745         if (urb->dev->speed == USB_SPEED_LOW)
 746                 return -EINVAL;
 747
 748         qh->skel = uhci->skel_bulk_qh;
 749         ret = uhci_submit_common(uhci, urb, qh);
 750         if (ret == 0)
 751                 uhci_inc_fsbr(uhci, urb);
 752         return ret;
 753 }
 754
 755 static inline int uhci_submit_interrupt(struct uhci_hcd *uhci, struct urb *urb,
 756                 struct uhci_qh *qh)
 757 {
 758         /* USB 1.1 interrupt transfers only involve one packet per interval.
 759          * Drivers can submit URBs of any length, but longer ones will need
 760          * multiple intervals to complete.
 761          */
 762         qh->skel = uhci->skelqh[__interval_to_skel(urb->interval)];
 763         return uhci_submit_common(uhci, urb, qh);
 764 }
 765
 766 /*
 767  * Fix up the data structures following a short transfer
 768  */
 769 static int uhci_fixup_short_transfer(struct uhci_hcd *uhci,
 770                 struct uhci_qh *qh, struct urb_priv *urbp,
 771                 struct uhci_td *short_td)
 772 {
 773         struct uhci_td *td;
 774         int ret = 0;
 775
 776         td = list_entry(urbp->td_list.prev, struct uhci_td, list);
 777         if (qh->type == USB_ENDPOINT_XFER_CONTROL) {
 778                 urbp->short_transfer = 1;
 779
 780                 /* When a control transfer is short, we have to restart
 781                  * the queue at the status stage transaction, which is
 782                  * the last TD. */
 783                 qh->element = cpu_to_le32(td->dma_handle);
 784                 ret = -EINPROGRESS;
 785
 786         } else if (!urbp->short_transfer) {
 787                 urbp->short_transfer = 1;
 788
 789                 /* When a bulk/interrupt transfer is short, we have to
 790                  * fix up the toggles of the following URBs on the queue
 791                  * before restarting the queue at the next URB. */
 792                 qh->initial_toggle = uhci_toggle(td_token(short_td)) ^ 1;
 793                 uhci_fixup_toggles(qh, 1);
 794
 795                 qh->element = td->link;
 796         }
 797
 798         return ret;
 799 }
 800
 801 /*
 802  * Common result for control, bulk, and interrupt
 803  */
 804 static int uhci_result_common(struct uhci_hcd *uhci, struct urb *urb)
 805 {
 806         struct urb_priv *urbp = urb->hcpriv;
 807         struct uhci_qh *qh = urbp->qh;
 808         struct uhci_td *td;
 809         struct list_head *tmp;
 810         unsigned status;
 811         int ret = 0;
 812
 813         tmp = urbp->td_list.next;
 814
 815         if (qh->type == USB_ENDPOINT_XFER_CONTROL) {
 816                 if (urbp->short_transfer)
 817                         tmp = urbp->td_list.prev;
 818                 else
 819                         urb->actual_length = -8;        /* SETUP packet */
 820         } else
 821                 urb->actual_length = 0;
 822
 823
 824         while (tmp != &urbp->td_list) {
 825                 unsigned int ctrlstat;
 826                 int len;
 827
 828                 td = list_entry(tmp, struct uhci_td, list);
 829                 tmp = tmp->next;
 830
 831                 ctrlstat = td_status(td);
 832                 status = uhci_status_bits(ctrlstat);
 833                 if (status & TD_CTRL_ACTIVE)
 834                         return -EINPROGRESS;
 835
 836                 len = uhci_actual_length(ctrlstat);
 837                 urb->actual_length += len;
 838
 839                 if (status) {
 840                         ret = uhci_map_status(status,
 841                                         uhci_packetout(td_token(td)));
 842                         if ((debug == 1 && ret != -EPIPE) || debug > 1) {
 843                                 /* Some debugging code */
 844                                 dev_dbg(uhci_dev(uhci),
 845                                                 "%s: failed with status %x\n",
 846                                                 __FUNCTION__, status);
 847
 848                                 if (debug > 1 && errbuf) {
 849                                         /* Print the chain for debugging */
 850                                         uhci_show_qh(urbp->qh, errbuf,
 851                                                         ERRBUF_LEN, 0);
 852                                         lprintk(errbuf);
 853                                 }
 854                         }
 855
 856                 } else if (len < uhci_expected_length(td_token(td))) {
 857
 858                         /* We received a short packet */
 859                         if (urb->transfer_flags & URB_SHORT_NOT_OK)
 860                                 ret = -EREMOTEIO;
 861                         else if (ctrlstat & TD_CTRL_SPD)
 862                                 ret = 1;
 863                 }
 864
 865                 if (ret != 0)
 866                         goto err;
 867         }
 868         return ret;
 869
 870 err:
 871         if (ret < 0) {
 872                 /* In case a control transfer gets an error
 873                  * during the setup stage */
 874                 urb->actual_length = max(urb->actual_length, 0);
 875
 876                 /* Note that the queue has stopped and save
 877                  * the next toggle value */
 878                 qh->element = UHCI_PTR_TERM;
 879                 qh->is_stopped = 1;
 880                 qh->needs_fixup = (qh->type != USB_ENDPOINT_XFER_CONTROL);
 881                 qh->initial_toggle = uhci_toggle(td_token(td)) ^
 882                                 (ret == -EREMOTEIO);
 883
 884         } else          /* Short packet received */
 885                 ret = uhci_fixup_short_transfer(uhci, qh, urbp, td);
 886         return ret;
 887 }
 888
 889 /*
 890  * Isochronous transfers
 891  */
 892 static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb,
 893                 struct uhci_qh *qh)
 894 {
 895         struct uhci_td *td = NULL;      /* Since urb->number_of_packets > 0 */
 896         int i, frame;
 897         unsigned long destination, status;
 898         struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;
 899
 900         if (urb->number_of_packets > 900)       /* 900? Why? */
 901                 return -EFBIG;
 902
 903         status = TD_CTRL_ACTIVE | TD_CTRL_IOS;
 904         destination = (urb->pipe & PIPE_DEVEP_MASK) | usb_packetid(urb->pipe);
 905
 906         /* Figure out the starting frame number */
 907         if (urb->transfer_flags & URB_ISO_ASAP) {
 908                 if (list_empty(&qh->queue)) {
 909                         uhci_get_current_frame_number(uhci);
 910                         urb->start_frame = (uhci->frame_number + 10);
 911
 912                 } else {                /* Go right after the last one */
 913                         struct urb *last_urb;
 914
 915                         last_urb = list_entry(qh->queue.prev,
 916                                         struct urb_priv, node)->urb;
 917                         urb->start_frame = (last_urb->start_frame +
 918                                         last_urb->number_of_packets *
 919                                         last_urb->interval);
 920                 }
 921         } else {
 922                 /* FIXME: Sanity check */
 923         }
 924         urb->start_frame &= (UHCI_NUMFRAMES - 1);
 925
 926         for (i = 0; i < urb->number_of_packets; i++) {
 927                 td = uhci_alloc_td(uhci);
 928                 if (!td)
 929                         return -ENOMEM;
 930
 931                 uhci_add_td_to_urb(urb, td);
 932                 uhci_fill_td(td, status, destination |
 933                                 uhci_explen(urb->iso_frame_desc[i].length),
 934                                 urb->transfer_dma +
 935                                         urb->iso_frame_desc[i].offset);
 936         }
 937
 938         /* Set the interrupt-on-completion flag on the last packet. */
 939         td->status |= __constant_cpu_to_le32(TD_CTRL_IOC);
 940
 941         qh->skel = uhci->skel_iso_qh;
 942
 943         /* Add the TDs to the frame list */
 944         frame = urb->start_frame;
 945         list_for_each_entry(td, &urbp->td_list, list) {
 946                 uhci_insert_td_in_frame_list(uhci, td, frame);
 947                 frame += urb->interval;
 948         }
 949
 950         return 0;
 951 }
 952
 953 static int uhci_result_isochronous(struct uhci_hcd *uhci, struct urb *urb)
 954 {
 955         struct uhci_td *td;
 956         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 957         int status;
 958         int i, ret = 0;
 959
 960         urb->actual_length = urb->error_count = 0;
 961
 962         i = 0;
 963         list_for_each_entry(td, &urbp->td_list, list) {
 964                 int actlength;
 965                 unsigned int ctrlstat = td_status(td);
 966
 967                 if (ctrlstat & TD_CTRL_ACTIVE)
 968                         return -EINPROGRESS;
 969
 970                 actlength = uhci_actual_length(ctrlstat);
 971                 urb->iso_frame_desc[i].actual_length = actlength;
 972                 urb->actual_length += actlength;
 973
 974                 status = uhci_map_status(uhci_status_bits(ctrlstat),
 975                                 usb_pipeout(urb->pipe));
 976                 urb->iso_frame_desc[i].status = status;
 977                 if (status) {
 978                         urb->error_count++;
 979                         ret = status;
 980                 }
 981
 982                 i++;
 983         }
 984
 985         return ret;
 986 }
 987
 988 static int uhci_urb_enqueue(struct usb_hcd *hcd,
 989                 struct usb_host_endpoint *hep,
 990                 struct urb *urb, gfp_t mem_flags)
 991 {
 992         int ret;
 993         struct uhci_hcd *uhci = hcd_to_uhci(hcd);
 994         unsigned long flags;
 995         struct urb_priv *urbp;
 996         struct uhci_qh *qh;
 997         int bustime;
 998
 999         spin_lock_irqsave(&uhci->lock, flags);
1000
1001         ret = urb->status;
1002         if (ret != -EINPROGRESS)                /* URB already unlinked! */
1003                 goto done;
1004
1005         ret = -ENOMEM;
1006         urbp = uhci_alloc_urb_priv(uhci, urb);
1007         if (!urbp)
1008                 goto done;
1009
1010         if (hep->hcpriv)
1011                 qh = (struct uhci_qh *) hep->hcpriv;
1012         else {
1013                 qh = uhci_alloc_qh(uhci, urb->dev, hep);
1014                 if (!qh)
1015                         goto err_no_qh;
1016         }
1017         urbp->qh = qh;
1018
1019         switch (qh->type) {
1020         case USB_ENDPOINT_XFER_CONTROL:
1021                 ret = uhci_submit_control(uhci, urb, qh);
1022                 break;
1023         case USB_ENDPOINT_XFER_BULK:
1024                 ret = uhci_submit_bulk(uhci, urb, qh);
1025                 break;
1026         case USB_ENDPOINT_XFER_INT:
1027                 if (list_empty(&qh->queue)) {
1028                         bustime = usb_check_bandwidth(urb->dev, urb);
1029                         if (bustime < 0)
1030                                 ret = bustime;
1031                         else {
1032                                 ret = uhci_submit_interrupt(uhci, urb, qh);
1033                                 if (ret == 0)
1034                                         usb_claim_bandwidth(urb->dev, urb, bustime, 0);
1035                         }
1036                 } else {        /* inherit from parent */
1037                         struct urb_priv *eurbp;
1038
1039                         eurbp = list_entry(qh->queue.prev, struct urb_priv,
1040                                         node);
1041                         urb->bandwidth = eurbp->urb->bandwidth;
1042                         ret = uhci_submit_interrupt(uhci, urb, qh);
1043                 }
1044                 break;
1045         case USB_ENDPOINT_XFER_ISOC:
1046                 bustime = usb_check_bandwidth(urb->dev, urb);
1047                 if (bustime < 0) {
1048                         ret = bustime;
1049                         break;
1050                 }
1051
1052                 ret = uhci_submit_isochronous(uhci, urb, qh);
1053                 if (ret == 0)
1054                         usb_claim_bandwidth(urb->dev, urb, bustime, 1);
1055                 break;
1056         }
1057         if (ret != 0)
1058                 goto err_submit_failed;
1059
1060         /* Add this URB to the QH */
1061         urbp->qh = qh;
1062         list_add_tail(&urbp->node, &qh->queue);
1063
1064         /* If the new URB is the first and only one on this QH then either
1065          * the QH is new and idle or else it's unlinked and waiting to
1066          * become idle, so we can activate it right away.  But only if the
1067          * queue isn't stopped. */
1068         if (qh->queue.next == &urbp->node && !qh->is_stopped)
1069                 uhci_activate_qh(uhci, qh);
1070         goto done;
1071
1072 err_submit_failed:
1073         if (qh->state == QH_STATE_IDLE)
1074                 uhci_make_qh_idle(uhci, qh);    /* Reclaim unused QH */
1075
1076 err_no_qh:
1077         uhci_free_urb_priv(uhci, urbp);
1078
1079 done:
1080         spin_unlock_irqrestore(&uhci->lock, flags);
1081         return ret;
1082 }
1083
1084 static int uhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb)
1085 {
1086         struct uhci_hcd *uhci = hcd_to_uhci(hcd);
1087         unsigned long flags;
1088         struct urb_priv *urbp;
1089
1090         spin_lock_irqsave(&uhci->lock, flags);
1091         urbp = urb->hcpriv;
1092         if (!urbp)                      /* URB was never linked! */
1093                 goto done;
1094
1095         /* Remove Isochronous TDs from the frame list ASAP */
1096         if (urbp->qh->type == USB_ENDPOINT_XFER_ISOC)
1097                 uhci_unlink_isochronous_tds(uhci, urb);
1098         uhci_unlink_qh(uhci, urbp->qh);
1099
1100 done:
1101         spin_unlock_irqrestore(&uhci->lock, flags);
1102         return 0;
1103 }
1104
1105 /*
1106  * Finish unlinking an URB and give it back
1107  */
1108 static void uhci_giveback_urb(struct uhci_hcd *uhci, struct uhci_qh *qh,
1109                 struct urb *urb, struct pt_regs *regs)
1110 __releases(uhci->lock)
1111 __acquires(uhci->lock)
1112 {
1113         struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;
1114
1115         /* Isochronous TDs get unlinked directly from the frame list */
1116         if (qh->type == USB_ENDPOINT_XFER_ISOC)
1117                 uhci_unlink_isochronous_tds(uhci, urb);
1118
1119         /* If the URB isn't first on its queue, adjust the link pointer
1120          * of the last TD in the previous URB. */
1121         else if (qh->queue.next != &urbp->node) {
1122                 struct urb_priv *purbp;
1123                 struct uhci_td *ptd, *ltd;
1124
1125                 purbp = list_entry(urbp->node.prev, struct urb_priv, node);
1126                 ptd = list_entry(purbp->td_list.prev, struct uhci_td,
1127                                 list);
1128                 ltd = list_entry(urbp->td_list.prev, struct uhci_td,
1129                                 list);
1130                 ptd->link = ltd->link;
1131         }
1132
1133         /* Take the URB off the QH's queue.  If the queue is now empty,
1134          * this is a perfect time for a toggle fixup. */
1135         list_del_init(&urbp->node);
1136         if (list_empty(&qh->queue) && qh->needs_fixup) {
1137                 usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
1138                                 usb_pipeout(urb->pipe), qh->initial_toggle);
1139                 qh->needs_fixup = 0;
1140         }
1141
1142         uhci_dec_fsbr(uhci, urb);       /* Safe since it checks */
1143         uhci_free_urb_priv(uhci, urbp);
1144
1145         switch (qh->type) {
1146         case USB_ENDPOINT_XFER_ISOC:
1147                 /* Release bandwidth for Interrupt or Isoc. transfers */
1148                 if (urb->bandwidth)
1149                         usb_release_bandwidth(urb->dev, urb, 1);
1150                 break;
1151         case USB_ENDPOINT_XFER_INT:
1152                 /* Release bandwidth for Interrupt or Isoc. transfers */
1153                 /* Make sure we don't release if we have a queued URB */
1154                 if (list_empty(&qh->queue) && urb->bandwidth)
1155                         usb_release_bandwidth(urb->dev, urb, 0);
1156                 else
1157                         /* bandwidth was passed on to queued URB, */
1158                         /* so don't let usb_unlink_urb() release it */
1159                         urb->bandwidth = 0;
1160                 break;
1161         }
1162
1163         spin_unlock(&uhci->lock);
1164         usb_hcd_giveback_urb(uhci_to_hcd(uhci), urb, regs);
1165         spin_lock(&uhci->lock);
1166
1167         /* If the queue is now empty, we can unlink the QH and give up its
1168          * reserved bandwidth. */
1169         if (list_empty(&qh->queue)) {
1170                 uhci_unlink_qh(uhci, qh);
1171
1172                 /* Bandwidth stuff not yet implemented */
1173         }
1174 }
1175
1176 /*
1177  * Scan the URBs in a QH's queue
1178  */
1179 #define QH_FINISHED_UNLINKING(qh)                       \
1180                 (qh->state == QH_STATE_UNLINKING &&     \
1181                 uhci->frame_number + uhci->is_stopped != qh->unlink_frame)
1182
1183 static void uhci_scan_qh(struct uhci_hcd *uhci, struct uhci_qh *qh,
1184                 struct pt_regs *regs)
1185 {
1186         struct urb_priv *urbp;
1187         struct urb *urb;
1188         int status;
1189
1190         while (!list_empty(&qh->queue)) {
1191                 urbp = list_entry(qh->queue.next, struct urb_priv, node);
1192                 urb = urbp->urb;
1193
1194                 if (qh->type == USB_ENDPOINT_XFER_ISOC)
1195                         status = uhci_result_isochronous(uhci, urb);
1196                 else
1197                         status = uhci_result_common(uhci, urb);
1198                 if (status == -EINPROGRESS)
1199                         break;
1200
1201                 spin_lock(&urb->lock);
1202                 if (urb->status == -EINPROGRESS)        /* Not dequeued */
1203                         urb->status = status;
1204                 else
1205                         status = ECONNRESET;            /* Not -ECONNRESET */
1206                 spin_unlock(&urb->lock);
1207
1208                 /* Dequeued but completed URBs can't be given back unless
1209                  * the QH is stopped or has finished unlinking. */
1210                 if (status == ECONNRESET) {
1211                         if (QH_FINISHED_UNLINKING(qh))
1212                                 qh->is_stopped = 1;
1213                         else if (!qh->is_stopped)
1214                                 return;
1215                 }
1216
1217                 uhci_giveback_urb(uhci, qh, urb, regs);
1218                 if (status < 0)
1219                         break;
1220         }
1221
1222         /* If the QH is neither stopped nor finished unlinking (normal case),
1223          * our work here is done. */
1224         if (QH_FINISHED_UNLINKING(qh))
1225                 qh->is_stopped = 1;
1226         else if (!qh->is_stopped)
1227                 return;
1228
1229         /* Otherwise give back each of the dequeued URBs */
1230 restart:
1231         list_for_each_entry(urbp, &qh->queue, node) {
1232                 urb = urbp->urb;
1233                 if (urb->status != -EINPROGRESS) {
1234                         uhci_save_toggle(qh, urb);
1235                         uhci_giveback_urb(uhci, qh, urb, regs);
1236                         goto restart;
1237                 }
1238         }
1239         qh->is_stopped = 0;
1240
1241         /* There are no more dequeued URBs.  If there are still URBs on the
1242          * queue, the QH can now be re-activated. */
1243         if (!list_empty(&qh->queue)) {
1244                 if (qh->needs_fixup)
1245                         uhci_fixup_toggles(qh, 0);
1246                 uhci_activate_qh(uhci, qh);
1247         }
1248
1249         /* The queue is empty.  The QH can become idle if it is fully
1250          * unlinked. */
1251         else if (QH_FINISHED_UNLINKING(qh))
1252                 uhci_make_qh_idle(uhci, qh);
1253 }
1254
1255 static void uhci_free_pending_tds(struct uhci_hcd *uhci)
1256 {
1257         struct uhci_td *td, *tmp;
1258
1259         list_for_each_entry_safe(td, tmp, &uhci->td_remove_list, remove_list) {
1260                 list_del_init(&td->remove_list);
1261
1262                 uhci_free_td(uhci, td);
1263         }
1264 }
1265
1266 /*
1267  * Process events in the schedule, but only in one thread at a time
1268  */
1269 static void uhci_scan_schedule(struct uhci_hcd *uhci, struct pt_regs *regs)
1270 {
1271         int i;
1272         struct uhci_qh *qh;
1273
1274         /* Don't allow re-entrant calls */
1275         if (uhci->scan_in_progress) {
1276                 uhci->need_rescan = 1;
1277                 return;
1278         }
1279         uhci->scan_in_progress = 1;
1280  rescan:
1281         uhci->need_rescan = 0;
1282
1283         uhci_clear_next_interrupt(uhci);
1284         uhci_get_current_frame_number(uhci);
1285
1286         if (uhci->frame_number + uhci->is_stopped != uhci->td_remove_age)
1287                 uhci_free_pending_tds(uhci);
1288
1289         /* Go through all the QH queues and process the URBs in each one */
1290         for (i = 0; i < UHCI_NUM_SKELQH - 1; ++i) {
1291                 uhci->next_qh = list_entry(uhci->skelqh[i]->node.next,
1292                                 struct uhci_qh, node);
1293                 while ((qh = uhci->next_qh) != uhci->skelqh[i]) {
1294                         uhci->next_qh = list_entry(qh->node.next,
1295                                         struct uhci_qh, node);
1296                         uhci_scan_qh(uhci, qh, regs);
1297                 }
1298         }
1299
1300         if (uhci->need_rescan)
1301                 goto rescan;
1302         uhci->scan_in_progress = 0;
1303
1304         /* If the controller is stopped, we can finish these off right now */
1305         if (uhci->is_stopped)
1306                 uhci_free_pending_tds(uhci);
1307
1308         if (list_empty(&uhci->td_remove_list) &&
1309                         list_empty(&uhci->skel_unlink_qh->node))
1310                 uhci_clear_next_interrupt(uhci);
1311         else
1312                 uhci_set_next_interrupt(uhci);
1313 }
1314
1315 static void check_fsbr(struct uhci_hcd *uhci)
1316 {
1317         /* For now, don't scan URBs for FSBR timeouts.
1318          * Add it back in later... */
1319
1320         /* Really disable FSBR */
1321         if (!uhci->fsbr && uhci->fsbrtimeout && time_after_eq(jiffies, uhci->fsbrtimeout)) {
1322                 uhci->fsbrtimeout = 0;
1323                 uhci->skel_term_qh->link = UHCI_PTR_TERM;
1324         }
1325 }