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
 183         } else {                /* Skeleton QH */
 184                 qh->state = QH_STATE_ACTIVE;
 185                 qh->udev = NULL;
 186         }
 187         return qh;
 188 }
 189
 190 static void uhci_free_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
 191 {
 192         WARN_ON(qh->state != QH_STATE_IDLE && qh->udev);
 193         if (!list_empty(&qh->queue))
 194                 dev_warn(uhci_dev(uhci), "qh %p list not empty!\n", qh);
 195
 196         list_del(&qh->node);
 197         if (qh->udev) {
 198                 qh->hep->hcpriv = NULL;
 199                 uhci_free_td(uhci, qh->dummy_td);
 200         }
 201         dma_pool_free(uhci->qh_pool, qh, qh->dma_handle);
 202 }
 203
 204 /*
 205  * When the currently executing URB is dequeued, save its current toggle value
 206  */
 207 static void uhci_save_toggle(struct uhci_qh *qh, struct urb *urb)
 208 {
 209         struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;
 210         struct uhci_td *td;
 211
 212         /* If the QH element pointer is UHCI_PTR_TERM then then currently
 213          * executing URB has already been unlinked, so this one isn't it. */
 214         if (qh_element(qh) == UHCI_PTR_TERM ||
 215                                 qh->queue.next != &urbp->node)
 216                 return;
 217         qh->element = UHCI_PTR_TERM;
 218
 219         /* Only bulk and interrupt pipes have to worry about toggles */
 220         if (!(usb_pipetype(urb->pipe) == PIPE_BULK ||
 221                         usb_pipetype(urb->pipe) == PIPE_INTERRUPT))
 222                 return;
 223
 224         /* Find the first active TD; that's the device's toggle state */
 225         list_for_each_entry(td, &urbp->td_list, list) {
 226                 if (td_status(td) & TD_CTRL_ACTIVE) {
 227                         qh->needs_fixup = 1;
 228                         qh->initial_toggle = uhci_toggle(td_token(td));
 229                         return;
 230                 }
 231         }
 232
 233         WARN_ON(1);
 234 }
 235
 236 /*
 237  * Fix up the data toggles for URBs in a queue, when one of them
 238  * terminates early (short transfer, error, or dequeued).
 239  */
 240 static void uhci_fixup_toggles(struct uhci_qh *qh, int skip_first)
 241 {
 242         struct urb_priv *urbp = NULL;
 243         struct uhci_td *td;
 244         unsigned int toggle = qh->initial_toggle;
 245         unsigned int pipe;
 246
 247         /* Fixups for a short transfer start with the second URB in the
 248          * queue (the short URB is the first). */
 249         if (skip_first)
 250                 urbp = list_entry(qh->queue.next, struct urb_priv, node);
 251
 252         /* When starting with the first URB, if the QH element pointer is
 253          * still valid then we know the URB's toggles are okay. */
 254         else if (qh_element(qh) != UHCI_PTR_TERM)
 255                 toggle = 2;
 256
 257         /* Fix up the toggle for the URBs in the queue.  Normally this
 258          * loop won't run more than once: When an error or short transfer
 259          * occurs, the queue usually gets emptied. */
 260         urbp = list_prepare_entry(urbp, &qh->queue, node);
 261         list_for_each_entry_continue(urbp, &qh->queue, node) {
 262
 263                 /* If the first TD has the right toggle value, we don't
 264                  * need to change any toggles in this URB */
 265                 td = list_entry(urbp->td_list.next, struct uhci_td, list);
 266                 if (toggle > 1 || uhci_toggle(td_token(td)) == toggle) {
 267                         td = list_entry(urbp->td_list.next, struct uhci_td,
 268                                         list);
 269                         toggle = uhci_toggle(td_token(td)) ^ 1;
 270
 271                 /* Otherwise all the toggles in the URB have to be switched */
 272                 } else {
 273                         list_for_each_entry(td, &urbp->td_list, list) {
 274                                 td->token ^= __constant_cpu_to_le32(
 275                                                         TD_TOKEN_TOGGLE);
 276                                 toggle ^= 1;
 277                         }
 278                 }
 279         }
 280
 281         wmb();
 282         pipe = list_entry(qh->queue.next, struct urb_priv, node)->urb->pipe;
 283         usb_settoggle(qh->udev, usb_pipeendpoint(pipe),
 284                         usb_pipeout(pipe), toggle);
 285         qh->needs_fixup = 0;
 286 }
 287
 288 /*
 289  * Put a QH on the schedule in both hardware and software
 290  */
 291 static void uhci_activate_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
 292 {
 293         struct uhci_qh *pqh;
 294
 295         WARN_ON(list_empty(&qh->queue));
 296
 297         /* Set the element pointer if it isn't set already.
 298          * This isn't needed for Isochronous queues, but it doesn't hurt. */
 299         if (qh_element(qh) == UHCI_PTR_TERM) {
 300                 struct urb_priv *urbp = list_entry(qh->queue.next,
 301                                 struct urb_priv, node);
 302                 struct uhci_td *td = list_entry(urbp->td_list.next,
 303                                 struct uhci_td, list);
 304
 305                 qh->element = cpu_to_le32(td->dma_handle);
 306         }
 307
 308         if (qh->state == QH_STATE_ACTIVE)
 309                 return;
 310         qh->state = QH_STATE_ACTIVE;
 311
 312         /* Move the QH from its old list to the end of the appropriate
 313          * skeleton's list */
 314         if (qh == uhci->next_qh)
 315                 uhci->next_qh = list_entry(qh->node.next, struct uhci_qh,
 316                                 node);
 317         list_move_tail(&qh->node, &qh->skel->node);
 318
 319         /* Link it into the schedule */
 320         pqh = list_entry(qh->node.prev, struct uhci_qh, node);
 321         qh->link = pqh->link;
 322         wmb();
 323         pqh->link = UHCI_PTR_QH | cpu_to_le32(qh->dma_handle);
 324 }
 325
 326 /*
 327  * Take a QH off the hardware schedule
 328  */
 329 static void uhci_unlink_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
 330 {
 331         struct uhci_qh *pqh;
 332
 333         if (qh->state == QH_STATE_UNLINKING)
 334                 return;
 335         WARN_ON(qh->state != QH_STATE_ACTIVE || !qh->udev);
 336         qh->state = QH_STATE_UNLINKING;
 337
 338         /* Unlink the QH from the schedule and record when we did it */
 339         pqh = list_entry(qh->node.prev, struct uhci_qh, node);
 340         pqh->link = qh->link;
 341         mb();
 342
 343         uhci_get_current_frame_number(uhci);
 344         qh->unlink_frame = uhci->frame_number;
 345
 346         /* Force an interrupt so we know when the QH is fully unlinked */
 347         if (list_empty(&uhci->skel_unlink_qh->node))
 348                 uhci_set_next_interrupt(uhci);
 349
 350         /* Move the QH from its old list to the end of the unlinking list */
 351         if (qh == uhci->next_qh)
 352                 uhci->next_qh = list_entry(qh->node.next, struct uhci_qh,
 353                                 node);
 354         list_move_tail(&qh->node, &uhci->skel_unlink_qh->node);
 355 }
 356
 357 /*
 358  * When we and the controller are through with a QH, it becomes IDLE.
 359  * This happens when a QH has been off the schedule (on the unlinking
 360  * list) for more than one frame, or when an error occurs while adding
 361  * the first URB onto a new QH.
 362  */
 363 static void uhci_make_qh_idle(struct uhci_hcd *uhci, struct uhci_qh *qh)
 364 {
 365         WARN_ON(qh->state == QH_STATE_ACTIVE);
 366
 367         if (qh == uhci->next_qh)
 368                 uhci->next_qh = list_entry(qh->node.next, struct uhci_qh,
 369                                 node);
 370         list_move(&qh->node, &uhci->idle_qh_list);
 371         qh->state = QH_STATE_IDLE;
 372
 373         /* If anyone is waiting for a QH to become idle, wake them up */
 374         if (uhci->num_waiting)
 375                 wake_up_all(&uhci->waitqh);
 376 }
 377
 378 static inline struct urb_priv *uhci_alloc_urb_priv(struct uhci_hcd *uhci,
 379                 struct urb *urb)
 380 {
 381         struct urb_priv *urbp;
 382
 383         urbp = kmem_cache_alloc(uhci_up_cachep, SLAB_ATOMIC);
 384         if (!urbp)
 385                 return NULL;
 386
 387         memset((void *)urbp, 0, sizeof(*urbp));
 388
 389         urbp->urb = urb;
 390         urb->hcpriv = urbp;
 391
 392         INIT_LIST_HEAD(&urbp->node);
 393         INIT_LIST_HEAD(&urbp->td_list);
 394
 395         return urbp;
 396 }
 397
 398 static void uhci_add_td_to_urb(struct urb *urb, struct uhci_td *td)
 399 {
 400         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 401
 402         list_add_tail(&td->list, &urbp->td_list);
 403 }
 404
 405 static void uhci_remove_td_from_urb(struct uhci_td *td)
 406 {
 407         if (list_empty(&td->list))
 408                 return;
 409
 410         list_del_init(&td->list);
 411 }
 412
 413 static void uhci_free_urb_priv(struct uhci_hcd *uhci,
 414                 struct urb_priv *urbp)
 415 {
 416         struct uhci_td *td, *tmp;
 417
 418         if (!list_empty(&urbp->node))
 419                 dev_warn(uhci_dev(uhci), "urb %p still on QH's list!\n",
 420                                 urbp->urb);
 421
 422         uhci_get_current_frame_number(uhci);
 423         if (uhci->frame_number + uhci->is_stopped != uhci->td_remove_age) {
 424                 uhci_free_pending_tds(uhci);
 425                 uhci->td_remove_age = uhci->frame_number;
 426         }
 427
 428         /* Check to see if the remove list is empty. Set the IOC bit */
 429         /* to force an interrupt so we can remove the TDs. */
 430         if (list_empty(&uhci->td_remove_list))
 431                 uhci_set_next_interrupt(uhci);
 432
 433         list_for_each_entry_safe(td, tmp, &urbp->td_list, list) {
 434                 uhci_remove_td_from_urb(td);
 435                 list_add(&td->remove_list, &uhci->td_remove_list);
 436         }
 437
 438         urbp->urb->hcpriv = NULL;
 439         kmem_cache_free(uhci_up_cachep, urbp);
 440 }
 441
 442 static void uhci_inc_fsbr(struct uhci_hcd *uhci, struct urb *urb)
 443 {
 444         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 445
 446         if ((!(urb->transfer_flags & URB_NO_FSBR)) && !urbp->fsbr) {
 447                 urbp->fsbr = 1;
 448                 if (!uhci->fsbr++ && !uhci->fsbrtimeout)
 449                         uhci->skel_term_qh->link = cpu_to_le32(uhci->skel_fs_control_qh->dma_handle) | UHCI_PTR_QH;
 450         }
 451 }
 452
 453 static void uhci_dec_fsbr(struct uhci_hcd *uhci, struct urb *urb)
 454 {
 455         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 456
 457         if ((!(urb->transfer_flags & URB_NO_FSBR)) && urbp->fsbr) {
 458                 urbp->fsbr = 0;
 459                 if (!--uhci->fsbr)
 460                         uhci->fsbrtimeout = jiffies + FSBR_DELAY;
 461         }
 462 }
 463
 464 /*
 465  * Map status to standard result codes
 466  *
 467  * <status> is (td_status(td) & 0xF60000), a.k.a.
 468  * uhci_status_bits(td_status(td)).
 469  * Note: <status> does not include the TD_CTRL_NAK bit.
 470  * <dir_out> is True for output TDs and False for input TDs.
 471  */
 472 static int uhci_map_status(int status, int dir_out)
 473 {
 474         if (!status)
 475                 return 0;
 476         if (status & TD_CTRL_BITSTUFF)                  /* Bitstuff error */
 477                 return -EPROTO;
 478         if (status & TD_CTRL_CRCTIMEO) {                /* CRC/Timeout */
 479                 if (dir_out)
 480                         return -EPROTO;
 481                 else
 482                         return -EILSEQ;
 483         }
 484         if (status & TD_CTRL_BABBLE)                    /* Babble */
 485                 return -EOVERFLOW;
 486         if (status & TD_CTRL_DBUFERR)                   /* Buffer error */
 487                 return -ENOSR;
 488         if (status & TD_CTRL_STALLED)                   /* Stalled */
 489                 return -EPIPE;
 490         WARN_ON(status & TD_CTRL_ACTIVE);               /* Active */
 491         return 0;
 492 }
 493
 494 /*
 495  * Control transfers
 496  */
 497 static int uhci_submit_control(struct uhci_hcd *uhci, struct urb *urb,
 498                 struct uhci_qh *qh)
 499 {
 500         struct uhci_td *td;
 501         unsigned long destination, status;
 502         int maxsze = le16_to_cpu(qh->hep->desc.wMaxPacketSize);
 503         int len = urb->transfer_buffer_length;
 504         dma_addr_t data = urb->transfer_dma;
 505         __le32 *plink;
 506
 507         /* The "pipe" thing contains the destination in bits 8--18 */
 508         destination = (urb->pipe & PIPE_DEVEP_MASK) | USB_PID_SETUP;
 509
 510         /* 3 errors, dummy TD remains inactive */
 511         status = uhci_maxerr(3);
 512         if (urb->dev->speed == USB_SPEED_LOW)
 513                 status |= TD_CTRL_LS;
 514
 515         /*
 516          * Build the TD for the control request setup packet
 517          */
 518         td = qh->dummy_td;
 519         uhci_add_td_to_urb(urb, td);
 520         uhci_fill_td(td, status, destination | uhci_explen(8),
 521                         urb->setup_dma);
 522         plink = &td->link;
 523         status |= TD_CTRL_ACTIVE;
 524
 525         /*
 526          * If direction is "send", change the packet ID from SETUP (0x2D)
 527          * to OUT (0xE1).  Else change it from SETUP to IN (0x69) and
 528          * set Short Packet Detect (SPD) for all data packets.
 529          */
 530         if (usb_pipeout(urb->pipe))
 531                 destination ^= (USB_PID_SETUP ^ USB_PID_OUT);
 532         else {
 533                 destination ^= (USB_PID_SETUP ^ USB_PID_IN);
 534                 status |= TD_CTRL_SPD;
 535         }
 536
 537         /*
 538          * Build the DATA TDs
 539          */
 540         while (len > 0) {
 541                 int pktsze = min(len, maxsze);
 542
 543                 td = uhci_alloc_td(uhci);
 544                 if (!td)
 545                         goto nomem;
 546                 *plink = cpu_to_le32(td->dma_handle);
 547
 548                 /* Alternate Data0/1 (start with Data1) */
 549                 destination ^= TD_TOKEN_TOGGLE;
 550
 551                 uhci_add_td_to_urb(urb, td);
 552                 uhci_fill_td(td, status, destination | uhci_explen(pktsze),
 553                                 data);
 554                 plink = &td->link;
 555
 556                 data += pktsze;
 557                 len -= pktsze;
 558         }
 559
 560         /*
 561          * Build the final TD for control status
 562          */
 563         td = uhci_alloc_td(uhci);
 564         if (!td)
 565                 goto nomem;
 566         *plink = cpu_to_le32(td->dma_handle);
 567
 568         /*
 569          * It's IN if the pipe is an output pipe or we're not expecting
 570          * data back.
 571          */
 572         destination &= ~TD_TOKEN_PID_MASK;
 573         if (usb_pipeout(urb->pipe) || !urb->transfer_buffer_length)
 574                 destination |= USB_PID_IN;
 575         else
 576                 destination |= USB_PID_OUT;
 577
 578         destination |= TD_TOKEN_TOGGLE;         /* End in Data1 */
 579
 580         status &= ~TD_CTRL_SPD;
 581
 582         uhci_add_td_to_urb(urb, td);
 583         uhci_fill_td(td, status | TD_CTRL_IOC,
 584                         destination | uhci_explen(0), 0);
 585         plink = &td->link;
 586
 587         /*
 588          * Build the new dummy TD and activate the old one
 589          */
 590         td = uhci_alloc_td(uhci);
 591         if (!td)
 592                 goto nomem;
 593         *plink = cpu_to_le32(td->dma_handle);
 594
 595         uhci_fill_td(td, 0, USB_PID_OUT | uhci_explen(0), 0);
 596         wmb();
 597         qh->dummy_td->status |= __constant_cpu_to_le32(TD_CTRL_ACTIVE);
 598         qh->dummy_td = td;
 599
 600         /* Low-speed transfers get a different queue, and won't hog the bus.
 601          * Also, some devices enumerate better without FSBR; the easiest way
 602          * to do that is to put URBs on the low-speed queue while the device
 603          * isn't in the CONFIGURED state. */
 604         if (urb->dev->speed == USB_SPEED_LOW ||
 605                         urb->dev->state != USB_STATE_CONFIGURED)
 606                 qh->skel = uhci->skel_ls_control_qh;
 607         else {
 608                 qh->skel = uhci->skel_fs_control_qh;
 609                 uhci_inc_fsbr(uhci, urb);
 610         }
 611         return 0;
 612
 613 nomem:
 614         /* Remove the dummy TD from the td_list so it doesn't get freed */
 615         uhci_remove_td_from_urb(qh->dummy_td);
 616         return -ENOMEM;
 617 }
 618
 619 /*
 620  * If control-IN transfer was short, the status packet wasn't sent.
 621  * This routine changes the element pointer in the QH to point at the
 622  * status TD.  It's safe to do this even while the QH is live, because
 623  * the hardware only updates the element pointer following a successful
 624  * transfer.  The inactive TD for the short packet won't cause an update,
 625  * so the pointer won't get overwritten.  The next time the controller
 626  * sees this QH, it will send the status packet.
 627  */
 628 static int usb_control_retrigger_status(struct uhci_hcd *uhci, struct urb *urb)
 629 {
 630         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 631         struct uhci_td *td;
 632
 633         urbp->short_transfer = 1;
 634
 635         td = list_entry(urbp->td_list.prev, struct uhci_td, list);
 636         urbp->qh->element = cpu_to_le32(td->dma_handle);
 637
 638         return -EINPROGRESS;
 639 }
 640
 641
 642 static int uhci_result_control(struct uhci_hcd *uhci, struct urb *urb)
 643 {
 644         struct list_head *tmp, *head;
 645         struct urb_priv *urbp = urb->hcpriv;
 646         struct uhci_td *td;
 647         unsigned int status;
 648         int ret = 0;
 649
 650         head = &urbp->td_list;
 651         if (urbp->short_transfer) {
 652                 tmp = head->prev;
 653                 goto status_stage;
 654         }
 655
 656         urb->actual_length = 0;
 657
 658         tmp = head->next;
 659         td = list_entry(tmp, struct uhci_td, list);
 660
 661         /* The first TD is the SETUP stage, check the status, but skip */
 662         /*  the count */
 663         status = uhci_status_bits(td_status(td));
 664         if (status & TD_CTRL_ACTIVE)
 665                 return -EINPROGRESS;
 666
 667         if (status)
 668                 goto td_error;
 669
 670         /* The rest of the TDs (but the last) are data */
 671         tmp = tmp->next;
 672         while (tmp != head && tmp->next != head) {
 673                 unsigned int ctrlstat;
 674
 675                 td = list_entry(tmp, struct uhci_td, list);
 676                 tmp = tmp->next;
 677
 678                 ctrlstat = td_status(td);
 679                 status = uhci_status_bits(ctrlstat);
 680                 if (status & TD_CTRL_ACTIVE)
 681                         return -EINPROGRESS;
 682
 683                 urb->actual_length += uhci_actual_length(ctrlstat);
 684
 685                 if (status)
 686                         goto td_error;
 687
 688                 /* Check to see if we received a short packet */
 689                 if (uhci_actual_length(ctrlstat) <
 690                                 uhci_expected_length(td_token(td))) {
 691                         if (urb->transfer_flags & URB_SHORT_NOT_OK) {
 692                                 ret = -EREMOTEIO;
 693                                 goto err;
 694                         }
 695
 696                         return usb_control_retrigger_status(uhci, urb);
 697                 }
 698         }
 699
 700 status_stage:
 701         td = list_entry(tmp, struct uhci_td, list);
 702
 703         /* Control status stage */
 704         status = td_status(td);
 705
 706 #ifdef I_HAVE_BUGGY_APC_BACKUPS
 707         /* APC BackUPS Pro kludge */
 708         /* It tries to send all of the descriptor instead of the amount */
 709         /*  we requested */
 710         if (status & TD_CTRL_IOC &&     /* IOC is masked out by uhci_status_bits */
 711             status & TD_CTRL_ACTIVE &&
 712             status & TD_CTRL_NAK)
 713                 return 0;
 714 #endif
 715
 716         status = uhci_status_bits(status);
 717         if (status & TD_CTRL_ACTIVE)
 718                 return -EINPROGRESS;
 719
 720         if (status)
 721                 goto td_error;
 722
 723         return 0;
 724
 725 td_error:
 726         ret = uhci_map_status(status, uhci_packetout(td_token(td)));
 727
 728 err:
 729         if ((debug == 1 && ret != -EPIPE) || debug > 1) {
 730                 /* Some debugging code */
 731                 dev_dbg(uhci_dev(uhci), "%s: failed with status %x\n",
 732                                 __FUNCTION__, status);
 733
 734                 if (errbuf) {
 735                         /* Print the chain for debugging purposes */
 736                         uhci_show_qh(urbp->qh, errbuf, ERRBUF_LEN, 0);
 737                         lprintk(errbuf);
 738                 }
 739         }
 740
 741         /* Note that the queue has stopped */
 742         urbp->qh->element = UHCI_PTR_TERM;
 743         urbp->qh->is_stopped = 1;
 744         return ret;
 745 }
 746
 747 /*
 748  * Common submit for bulk and interrupt
 749  */
 750 static int uhci_submit_common(struct uhci_hcd *uhci, struct urb *urb,
 751                 struct uhci_qh *qh)
 752 {
 753         struct uhci_td *td;
 754         unsigned long destination, status;
 755         int maxsze = le16_to_cpu(qh->hep->desc.wMaxPacketSize);
 756         int len = urb->transfer_buffer_length;
 757         dma_addr_t data = urb->transfer_dma;
 758         __le32 *plink;
 759         unsigned int toggle;
 760
 761         if (len < 0)
 762                 return -EINVAL;
 763
 764         /* The "pipe" thing contains the destination in bits 8--18 */
 765         destination = (urb->pipe & PIPE_DEVEP_MASK) | usb_packetid(urb->pipe);
 766         toggle = usb_gettoggle(urb->dev, usb_pipeendpoint(urb->pipe),
 767                          usb_pipeout(urb->pipe));
 768
 769         /* 3 errors, dummy TD remains inactive */
 770         status = uhci_maxerr(3);
 771         if (urb->dev->speed == USB_SPEED_LOW)
 772                 status |= TD_CTRL_LS;
 773         if (usb_pipein(urb->pipe))
 774                 status |= TD_CTRL_SPD;
 775
 776         /*
 777          * Build the DATA TDs
 778          */
 779         plink = NULL;
 780         td = qh->dummy_td;
 781         do {    /* Allow zero length packets */
 782                 int pktsze = maxsze;
 783
 784                 if (len <= pktsze) {            /* The last packet */
 785                         pktsze = len;
 786                         if (!(urb->transfer_flags & URB_SHORT_NOT_OK))
 787                                 status &= ~TD_CTRL_SPD;
 788                 }
 789
 790                 if (plink) {
 791                         td = uhci_alloc_td(uhci);
 792                         if (!td)
 793                                 goto nomem;
 794                         *plink = cpu_to_le32(td->dma_handle);
 795                 }
 796                 uhci_add_td_to_urb(urb, td);
 797                 uhci_fill_td(td, status,
 798                                 destination | uhci_explen(pktsze) |
 799                                         (toggle << TD_TOKEN_TOGGLE_SHIFT),
 800                                 data);
 801                 plink = &td->link;
 802                 status |= TD_CTRL_ACTIVE;
 803
 804                 data += pktsze;
 805                 len -= maxsze;
 806                 toggle ^= 1;
 807         } while (len > 0);
 808
 809         /*
 810          * URB_ZERO_PACKET means adding a 0-length packet, if direction
 811          * is OUT and the transfer_length was an exact multiple of maxsze,
 812          * hence (len = transfer_length - N * maxsze) == 0
 813          * however, if transfer_length == 0, the zero packet was already
 814          * prepared above.
 815          */
 816         if ((urb->transfer_flags & URB_ZERO_PACKET) &&
 817                         usb_pipeout(urb->pipe) && len == 0 &&
 818                         urb->transfer_buffer_length > 0) {
 819                 td = uhci_alloc_td(uhci);
 820                 if (!td)
 821                         goto nomem;
 822                 *plink = cpu_to_le32(td->dma_handle);
 823
 824                 uhci_add_td_to_urb(urb, td);
 825                 uhci_fill_td(td, status,
 826                                 destination | uhci_explen(0) |
 827                                         (toggle << TD_TOKEN_TOGGLE_SHIFT),
 828                                 data);
 829                 plink = &td->link;
 830
 831                 toggle ^= 1;
 832         }
 833
 834         /* Set the interrupt-on-completion flag on the last packet.
 835          * A more-or-less typical 4 KB URB (= size of one memory page)
 836          * will require about 3 ms to transfer; that's a little on the
 837          * fast side but not enough to justify delaying an interrupt
 838          * more than 2 or 3 URBs, so we will ignore the URB_NO_INTERRUPT
 839          * flag setting. */
 840         td->status |= __constant_cpu_to_le32(TD_CTRL_IOC);
 841
 842         /*
 843          * Build the new dummy TD and activate the old one
 844          */
 845         td = uhci_alloc_td(uhci);
 846         if (!td)
 847                 goto nomem;
 848         *plink = cpu_to_le32(td->dma_handle);
 849
 850         uhci_fill_td(td, 0, USB_PID_OUT | uhci_explen(0), 0);
 851         wmb();
 852         qh->dummy_td->status |= __constant_cpu_to_le32(TD_CTRL_ACTIVE);
 853         qh->dummy_td = td;
 854
 855         usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
 856                         usb_pipeout(urb->pipe), toggle);
 857         return 0;
 858
 859 nomem:
 860         /* Remove the dummy TD from the td_list so it doesn't get freed */
 861         uhci_remove_td_from_urb(qh->dummy_td);
 862         return -ENOMEM;
 863 }
 864
 865 /*
 866  * Common result for bulk and interrupt
 867  */
 868 static int uhci_result_common(struct uhci_hcd *uhci, struct urb *urb)
 869 {
 870         struct urb_priv *urbp = urb->hcpriv;
 871         struct uhci_td *td;
 872         unsigned int status = 0;
 873         int ret = 0;
 874
 875         urb->actual_length = 0;
 876
 877         list_for_each_entry(td, &urbp->td_list, list) {
 878                 unsigned int ctrlstat = td_status(td);
 879
 880                 status = uhci_status_bits(ctrlstat);
 881                 if (status & TD_CTRL_ACTIVE)
 882                         return -EINPROGRESS;
 883
 884                 urb->actual_length += uhci_actual_length(ctrlstat);
 885
 886                 if (status)
 887                         goto td_error;
 888
 889                 if (uhci_actual_length(ctrlstat) <
 890                                 uhci_expected_length(td_token(td))) {
 891                         if (urb->transfer_flags & URB_SHORT_NOT_OK) {
 892                                 ret = -EREMOTEIO;
 893                                 goto err;
 894                         }
 895
 896                         /*
 897                          * This URB stopped short of its end.  We have to
 898                          * fix up the toggles of the following URBs on the
 899                          * queue and restart the queue.
 900                          *
 901                          * Do this only the first time we encounter the
 902                          * short URB.
 903                          */
 904                         if (!urbp->short_transfer) {
 905                                 urbp->short_transfer = 1;
 906                                 urbp->qh->initial_toggle =
 907                                                 uhci_toggle(td_token(td)) ^ 1;
 908                                 uhci_fixup_toggles(urbp->qh, 1);
 909
 910                                 td = list_entry(urbp->td_list.prev,
 911                                                 struct uhci_td, list);
 912                                 urbp->qh->element = td->link;
 913                         }
 914                         break;
 915                 }
 916         }
 917
 918         return 0;
 919
 920 td_error:
 921         ret = uhci_map_status(status, uhci_packetout(td_token(td)));
 922
 923         if ((debug == 1 && ret != -EPIPE) || debug > 1) {
 924                 /* Some debugging code */
 925                 dev_dbg(uhci_dev(uhci), "%s: failed with status %x\n",
 926                                 __FUNCTION__, status);
 927
 928                 if (debug > 1 && errbuf) {
 929                         /* Print the chain for debugging purposes */
 930                         uhci_show_qh(urbp->qh, errbuf, ERRBUF_LEN, 0);
 931                         lprintk(errbuf);
 932                 }
 933         }
 934 err:
 935
 936         /* Note that the queue has stopped and save the next toggle value */
 937         urbp->qh->element = UHCI_PTR_TERM;
 938         urbp->qh->is_stopped = 1;
 939         urbp->qh->needs_fixup = 1;
 940         urbp->qh->initial_toggle = uhci_toggle(td_token(td)) ^
 941                         (ret == -EREMOTEIO);
 942         return ret;
 943 }
 944
 945 static inline int uhci_submit_bulk(struct uhci_hcd *uhci, struct urb *urb,
 946                 struct uhci_qh *qh)
 947 {
 948         int ret;
 949
 950         /* Can't have low-speed bulk transfers */
 951         if (urb->dev->speed == USB_SPEED_LOW)
 952                 return -EINVAL;
 953
 954         qh->skel = uhci->skel_bulk_qh;
 955         ret = uhci_submit_common(uhci, urb, qh);
 956         if (ret == 0)
 957                 uhci_inc_fsbr(uhci, urb);
 958         return ret;
 959 }
 960
 961 static inline int uhci_submit_interrupt(struct uhci_hcd *uhci, struct urb *urb,
 962                 struct uhci_qh *qh)
 963 {
 964         /* USB 1.1 interrupt transfers only involve one packet per interval.
 965          * Drivers can submit URBs of any length, but longer ones will need
 966          * multiple intervals to complete.
 967          */
 968         qh->skel = uhci->skelqh[__interval_to_skel(urb->interval)];
 969         return uhci_submit_common(uhci, urb, qh);
 970 }
 971
 972 /*
 973  * Isochronous transfers
 974  */
 975 static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb,
 976                 struct uhci_qh *qh)
 977 {
 978         struct uhci_td *td = NULL;      /* Since urb->number_of_packets > 0 */
 979         int i, frame;
 980         unsigned long destination, status;
 981         struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;
 982
 983         if (urb->number_of_packets > 900)       /* 900? Why? */
 984                 return -EFBIG;
 985
 986         status = TD_CTRL_ACTIVE | TD_CTRL_IOS;
 987         destination = (urb->pipe & PIPE_DEVEP_MASK) | usb_packetid(urb->pipe);
 988
 989         /* Figure out the starting frame number */
 990         if (urb->transfer_flags & URB_ISO_ASAP) {
 991                 if (list_empty(&qh->queue)) {
 992                         uhci_get_current_frame_number(uhci);
 993                         urb->start_frame = (uhci->frame_number + 10);
 994
 995                 } else {                /* Go right after the last one */
 996                         struct urb *last_urb;
 997
 998                         last_urb = list_entry(qh->queue.prev,
 999                                         struct urb_priv, node)->urb;
1000                         urb->start_frame = (last_urb->start_frame +
1001                                         last_urb->number_of_packets *
1002                                         last_urb->interval);
1003                 }
1004         } else {
1005                 /* FIXME: Sanity check */
1006         }
1007         urb->start_frame &= (UHCI_NUMFRAMES - 1);
1008
1009         for (i = 0; i < urb->number_of_packets; i++) {
1010                 td = uhci_alloc_td(uhci);
1011                 if (!td)
1012                         return -ENOMEM;
1013
1014                 uhci_add_td_to_urb(urb, td);
1015                 uhci_fill_td(td, status, destination |
1016                                 uhci_explen(urb->iso_frame_desc[i].length),
1017                                 urb->transfer_dma +
1018                                         urb->iso_frame_desc[i].offset);
1019         }
1020
1021         /* Set the interrupt-on-completion flag on the last packet. */
1022         td->status |= __constant_cpu_to_le32(TD_CTRL_IOC);
1023
1024         qh->skel = uhci->skel_iso_qh;
1025
1026         /* Add the TDs to the frame list */
1027         frame = urb->start_frame;
1028         list_for_each_entry(td, &urbp->td_list, list) {
1029                 uhci_insert_td_in_frame_list(uhci, td, frame);
1030                 frame += urb->interval;
1031         }
1032
1033         return 0;
1034 }
1035
1036 static int uhci_result_isochronous(struct uhci_hcd *uhci, struct urb *urb)
1037 {
1038         struct uhci_td *td;
1039         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
1040         int status;
1041         int i, ret = 0;
1042
1043         urb->actual_length = urb->error_count = 0;
1044
1045         i = 0;
1046         list_for_each_entry(td, &urbp->td_list, list) {
1047                 int actlength;
1048                 unsigned int ctrlstat = td_status(td);
1049
1050                 if (ctrlstat & TD_CTRL_ACTIVE)
1051                         return -EINPROGRESS;
1052
1053                 actlength = uhci_actual_length(ctrlstat);
1054                 urb->iso_frame_desc[i].actual_length = actlength;
1055                 urb->actual_length += actlength;
1056
1057                 status = uhci_map_status(uhci_status_bits(ctrlstat),
1058                                 usb_pipeout(urb->pipe));
1059                 urb->iso_frame_desc[i].status = status;
1060                 if (status) {
1061                         urb->error_count++;
1062                         ret = status;
1063                 }
1064
1065                 i++;
1066         }
1067
1068         return ret;
1069 }
1070
1071 static int uhci_urb_enqueue(struct usb_hcd *hcd,
1072                 struct usb_host_endpoint *hep,
1073                 struct urb *urb, gfp_t mem_flags)
1074 {
1075         int ret;
1076         struct uhci_hcd *uhci = hcd_to_uhci(hcd);
1077         unsigned long flags;
1078         struct urb_priv *urbp;
1079         struct uhci_qh *qh;
1080         int bustime;
1081
1082         spin_lock_irqsave(&uhci->lock, flags);
1083
1084         ret = urb->status;
1085         if (ret != -EINPROGRESS)                /* URB already unlinked! */
1086                 goto done;
1087
1088         ret = -ENOMEM;
1089         urbp = uhci_alloc_urb_priv(uhci, urb);
1090         if (!urbp)
1091                 goto done;
1092
1093         if (hep->hcpriv)
1094                 qh = (struct uhci_qh *) hep->hcpriv;
1095         else {
1096                 qh = uhci_alloc_qh(uhci, urb->dev, hep);
1097                 if (!qh)
1098                         goto err_no_qh;
1099         }
1100         urbp->qh = qh;
1101
1102         switch (usb_pipetype(urb->pipe)) {
1103         case PIPE_CONTROL:
1104                 ret = uhci_submit_control(uhci, urb, qh);
1105                 break;
1106         case PIPE_BULK:
1107                 ret = uhci_submit_bulk(uhci, urb, qh);
1108                 break;
1109         case PIPE_INTERRUPT:
1110                 if (list_empty(&qh->queue)) {
1111                         bustime = usb_check_bandwidth(urb->dev, urb);
1112                         if (bustime < 0)
1113                                 ret = bustime;
1114                         else {
1115                                 ret = uhci_submit_interrupt(uhci, urb, qh);
1116                                 if (ret == 0)
1117                                         usb_claim_bandwidth(urb->dev, urb, bustime, 0);
1118                         }
1119                 } else {        /* inherit from parent */
1120                         struct urb_priv *eurbp;
1121
1122                         eurbp = list_entry(qh->queue.prev, struct urb_priv,
1123                                         node);
1124                         urb->bandwidth = eurbp->urb->bandwidth;
1125                         ret = uhci_submit_interrupt(uhci, urb, qh);
1126                 }
1127                 break;
1128         case PIPE_ISOCHRONOUS:
1129                 bustime = usb_check_bandwidth(urb->dev, urb);
1130                 if (bustime < 0) {
1131                         ret = bustime;
1132                         break;
1133                 }
1134
1135                 ret = uhci_submit_isochronous(uhci, urb, qh);
1136                 if (ret == 0)
1137                         usb_claim_bandwidth(urb->dev, urb, bustime, 1);
1138                 break;
1139         }
1140         if (ret != 0)
1141                 goto err_submit_failed;
1142
1143         /* Add this URB to the QH */
1144         urbp->qh = qh;
1145         list_add_tail(&urbp->node, &qh->queue);
1146
1147         /* If the new URB is the first and only one on this QH then either
1148          * the QH is new and idle or else it's unlinked and waiting to
1149          * become idle, so we can activate it right away. */
1150         if (qh->queue.next == &urbp->node)
1151                 uhci_activate_qh(uhci, qh);
1152         goto done;
1153
1154 err_submit_failed:
1155         if (qh->state == QH_STATE_IDLE)
1156                 uhci_make_qh_idle(uhci, qh);    /* Reclaim unused QH */
1157
1158 err_no_qh:
1159         uhci_free_urb_priv(uhci, urbp);
1160
1161 done:
1162         spin_unlock_irqrestore(&uhci->lock, flags);
1163         return ret;
1164 }
1165
1166 static int uhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb)
1167 {
1168         struct uhci_hcd *uhci = hcd_to_uhci(hcd);
1169         unsigned long flags;
1170         struct urb_priv *urbp;
1171
1172         spin_lock_irqsave(&uhci->lock, flags);
1173         urbp = urb->hcpriv;
1174         if (!urbp)                      /* URB was never linked! */
1175                 goto done;
1176
1177         /* Remove Isochronous TDs from the frame list ASAP */
1178         if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS)
1179                 uhci_unlink_isochronous_tds(uhci, urb);
1180         uhci_unlink_qh(uhci, urbp->qh);
1181
1182 done:
1183         spin_unlock_irqrestore(&uhci->lock, flags);
1184         return 0;
1185 }
1186
1187 /*
1188  * Finish unlinking an URB and give it back
1189  */
1190 static void uhci_giveback_urb(struct uhci_hcd *uhci, struct uhci_qh *qh,
1191                 struct urb *urb, struct pt_regs *regs)
1192 __releases(uhci->lock)
1193 __acquires(uhci->lock)
1194 {
1195         struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;
1196
1197         /* Isochronous TDs get unlinked directly from the frame list */
1198         if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS)
1199                 uhci_unlink_isochronous_tds(uhci, urb);
1200
1201         /* If the URB isn't first on its queue, adjust the link pointer
1202          * of the last TD in the previous URB. */
1203         else if (qh->queue.next != &urbp->node) {
1204                 struct urb_priv *purbp;
1205                 struct uhci_td *ptd, *ltd;
1206
1207                 purbp = list_entry(urbp->node.prev, struct urb_priv, node);
1208                 ptd = list_entry(purbp->td_list.prev, struct uhci_td,
1209                                 list);
1210                 ltd = list_entry(urbp->td_list.prev, struct uhci_td,
1211                                 list);
1212                 ptd->link = ltd->link;
1213         }
1214
1215         /* Take the URB off the QH's queue.  If the queue is now empty,
1216          * this is a perfect time for a toggle fixup. */
1217         list_del_init(&urbp->node);
1218         if (list_empty(&qh->queue) && qh->needs_fixup) {
1219                 usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
1220                                 usb_pipeout(urb->pipe), qh->initial_toggle);
1221                 qh->needs_fixup = 0;
1222         }
1223
1224         uhci_dec_fsbr(uhci, urb);       /* Safe since it checks */
1225         uhci_free_urb_priv(uhci, urbp);
1226
1227         switch (usb_pipetype(urb->pipe)) {
1228         case PIPE_ISOCHRONOUS:
1229                 /* Release bandwidth for Interrupt or Isoc. transfers */
1230                 if (urb->bandwidth)
1231                         usb_release_bandwidth(urb->dev, urb, 1);
1232                 break;
1233         case PIPE_INTERRUPT:
1234                 /* Release bandwidth for Interrupt or Isoc. transfers */
1235                 /* Make sure we don't release if we have a queued URB */
1236                 if (list_empty(&qh->queue) && urb->bandwidth)
1237                         usb_release_bandwidth(urb->dev, urb, 0);
1238                 else
1239                         /* bandwidth was passed on to queued URB, */
1240                         /* so don't let usb_unlink_urb() release it */
1241                         urb->bandwidth = 0;
1242                 break;
1243         }
1244
1245         spin_unlock(&uhci->lock);
1246         usb_hcd_giveback_urb(uhci_to_hcd(uhci), urb, regs);
1247         spin_lock(&uhci->lock);
1248
1249         /* If the queue is now empty, we can unlink the QH and give up its
1250          * reserved bandwidth. */
1251         if (list_empty(&qh->queue)) {
1252                 uhci_unlink_qh(uhci, qh);
1253
1254                 /* Bandwidth stuff not yet implemented */
1255         }
1256 }
1257
1258 /*
1259  * Scan the URBs in a QH's queue
1260  */
1261 #define QH_FINISHED_UNLINKING(qh)                       \
1262                 (qh->state == QH_STATE_UNLINKING &&     \
1263                 uhci->frame_number + uhci->is_stopped != qh->unlink_frame)
1264
1265 static void uhci_scan_qh(struct uhci_hcd *uhci, struct uhci_qh *qh,
1266                 struct pt_regs *regs)
1267 {
1268         struct urb_priv *urbp;
1269         struct urb *urb;
1270         int status;
1271
1272         while (!list_empty(&qh->queue)) {
1273                 urbp = list_entry(qh->queue.next, struct urb_priv, node);
1274                 urb = urbp->urb;
1275
1276                 switch (usb_pipetype(urb->pipe)) {
1277                 case PIPE_CONTROL:
1278                         status = uhci_result_control(uhci, urb);
1279                         break;
1280                 case PIPE_ISOCHRONOUS:
1281                         status = uhci_result_isochronous(uhci, urb);
1282                         break;
1283                 default:        /* PIPE_BULK or PIPE_INTERRUPT */
1284                         status = uhci_result_common(uhci, urb);
1285                         break;
1286                 }
1287                 if (status == -EINPROGRESS)
1288                         break;
1289
1290                 spin_lock(&urb->lock);
1291                 if (urb->status == -EINPROGRESS)        /* Not dequeued */
1292                         urb->status = status;
1293                 else
1294                         status = -ECONNRESET;
1295                 spin_unlock(&urb->lock);
1296
1297                 /* Dequeued but completed URBs can't be given back unless
1298                  * the QH is stopped or has finished unlinking. */
1299                 if (status == -ECONNRESET &&
1300                                 !(qh->is_stopped || QH_FINISHED_UNLINKING(qh)))
1301                         return;
1302
1303                 uhci_giveback_urb(uhci, qh, urb, regs);
1304                 if (qh->is_stopped)
1305                         break;
1306         }
1307
1308         /* If the QH is neither stopped nor finished unlinking (normal case),
1309          * our work here is done. */
1310  restart:
1311         if (!(qh->is_stopped || QH_FINISHED_UNLINKING(qh)))
1312                 return;
1313
1314         /* Otherwise give back each of the dequeued URBs */
1315         list_for_each_entry(urbp, &qh->queue, node) {
1316                 urb = urbp->urb;
1317                 if (urb->status != -EINPROGRESS) {
1318                         uhci_save_toggle(qh, urb);
1319                         uhci_giveback_urb(uhci, qh, urb, regs);
1320                         goto restart;
1321                 }
1322         }
1323         qh->is_stopped = 0;
1324
1325         /* There are no more dequeued URBs.  If there are still URBs on the
1326          * queue, the QH can now be re-activated. */
1327         if (!list_empty(&qh->queue)) {
1328                 if (qh->needs_fixup)
1329                         uhci_fixup_toggles(qh, 0);
1330                 uhci_activate_qh(uhci, qh);
1331         }
1332
1333         /* The queue is empty.  The QH can become idle if it is fully
1334          * unlinked. */
1335         else if (QH_FINISHED_UNLINKING(qh))
1336                 uhci_make_qh_idle(uhci, qh);
1337 }
1338
1339 static void uhci_free_pending_tds(struct uhci_hcd *uhci)
1340 {
1341         struct uhci_td *td, *tmp;
1342
1343         list_for_each_entry_safe(td, tmp, &uhci->td_remove_list, remove_list) {
1344                 list_del_init(&td->remove_list);
1345
1346                 uhci_free_td(uhci, td);
1347         }
1348 }
1349
1350 /*
1351  * Process events in the schedule, but only in one thread at a time
1352  */
1353 static void uhci_scan_schedule(struct uhci_hcd *uhci, struct pt_regs *regs)
1354 {
1355         int i;
1356         struct uhci_qh *qh;
1357
1358         /* Don't allow re-entrant calls */
1359         if (uhci->scan_in_progress) {
1360                 uhci->need_rescan = 1;
1361                 return;
1362         }
1363         uhci->scan_in_progress = 1;
1364  rescan:
1365         uhci->need_rescan = 0;
1366
1367         uhci_clear_next_interrupt(uhci);
1368         uhci_get_current_frame_number(uhci);
1369
1370         if (uhci->frame_number + uhci->is_stopped != uhci->td_remove_age)
1371                 uhci_free_pending_tds(uhci);
1372
1373         /* Go through all the QH queues and process the URBs in each one */
1374         for (i = 0; i < UHCI_NUM_SKELQH - 1; ++i) {
1375                 uhci->next_qh = list_entry(uhci->skelqh[i]->node.next,
1376                                 struct uhci_qh, node);
1377                 while ((qh = uhci->next_qh) != uhci->skelqh[i]) {
1378                         uhci->next_qh = list_entry(qh->node.next,
1379                                         struct uhci_qh, node);
1380                         uhci_scan_qh(uhci, qh, regs);
1381                 }
1382         }
1383
1384         if (uhci->need_rescan)
1385                 goto rescan;
1386         uhci->scan_in_progress = 0;
1387
1388         /* If the controller is stopped, we can finish these off right now */
1389         if (uhci->is_stopped)
1390                 uhci_free_pending_tds(uhci);
1391
1392         if (list_empty(&uhci->td_remove_list) &&
1393                         list_empty(&uhci->skel_unlink_qh->node))
1394                 uhci_clear_next_interrupt(uhci);
1395         else
1396                 uhci_set_next_interrupt(uhci);
1397 }
1398
1399 static void check_fsbr(struct uhci_hcd *uhci)
1400 {
1401         /* For now, don't scan URBs for FSBR timeouts.
1402          * Add it back in later... */
1403
1404         /* Really disable FSBR */
1405         if (!uhci->fsbr && uhci->fsbrtimeout && time_after_eq(jiffies, uhci->fsbrtimeout)) {
1406                 uhci->fsbrtimeout = 0;
1407                 uhci->skel_term_qh->link = UHCI_PTR_TERM;
1408         }
1409 }