err.no Git - linux-2.6/blob - 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 Alan Stern, stern@rowland.harvard.edu
  17  */
  18
  19 static int uhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb);
  20 static void uhci_unlink_generic(struct uhci_hcd *uhci, struct urb *urb);
  21 static void uhci_remove_pending_urbps(struct uhci_hcd *uhci);
  22 static void uhci_free_pending_qhs(struct uhci_hcd *uhci);
  23 static void uhci_free_pending_tds(struct uhci_hcd *uhci);
  24
  25 /*
  26  * Technically, updating td->status here is a race, but it's not really a
  27  * problem. The worst that can happen is that we set the IOC bit again
  28  * generating a spurious interrupt. We could fix this by creating another
  29  * QH and leaving the IOC bit always set, but then we would have to play
  30  * games with the FSBR code to make sure we get the correct order in all
  31  * the cases. I don't think it's worth the effort
  32  */
  33 static inline void uhci_set_next_interrupt(struct uhci_hcd *uhci)
  34 {
  35         if (uhci->is_stopped)
  36                 mod_timer(&uhci->stall_timer, jiffies);
  37         uhci->term_td->status |= cpu_to_le32(TD_CTRL_IOC);
  38 }
  39
  40 static inline void uhci_clear_next_interrupt(struct uhci_hcd *uhci)
  41 {
  42         uhci->term_td->status &= ~cpu_to_le32(TD_CTRL_IOC);
  43 }
  44
  45 static inline void uhci_moveto_complete(struct uhci_hcd *uhci,
  46                                         struct urb_priv *urbp)
  47 {
  48         list_move_tail(&urbp->urb_list, &uhci->complete_list);
  49 }
  50
  51 static struct uhci_td *uhci_alloc_td(struct uhci_hcd *uhci)
  52 {
  53         dma_addr_t dma_handle;
  54         struct uhci_td *td;
  55
  56         td = dma_pool_alloc(uhci->td_pool, GFP_ATOMIC, &dma_handle);
  57         if (!td)
  58                 return NULL;
  59
  60         td->dma_handle = dma_handle;
  61
  62         td->link = UHCI_PTR_TERM;
  63         td->buffer = 0;
  64
  65         td->frame = -1;
  66
  67         INIT_LIST_HEAD(&td->list);
  68         INIT_LIST_HEAD(&td->remove_list);
  69         INIT_LIST_HEAD(&td->fl_list);
  70
  71         return td;
  72 }
  73
  74 static inline void uhci_fill_td(struct uhci_td *td, u32 status,
  75                 u32 token, u32 buffer)
  76 {
  77         td->status = cpu_to_le32(status);
  78         td->token = cpu_to_le32(token);
  79         td->buffer = cpu_to_le32(buffer);
  80 }
  81
  82 /*
  83  * We insert Isochronous URB's directly into the frame list at the beginning
  84  */
  85 static void uhci_insert_td_frame_list(struct uhci_hcd *uhci, struct uhci_td *td, unsigned framenum)
  86 {
  87         framenum &= (UHCI_NUMFRAMES - 1);
  88
  89         td->frame = framenum;
  90
  91         /* Is there a TD already mapped there? */
  92         if (uhci->fl->frame_cpu[framenum]) {
  93                 struct uhci_td *ftd, *ltd;
  94
  95                 ftd = uhci->fl->frame_cpu[framenum];
  96                 ltd = list_entry(ftd->fl_list.prev, struct uhci_td, fl_list);
  97
  98                 list_add_tail(&td->fl_list, &ftd->fl_list);
  99
 100                 td->link = ltd->link;
 101                 wmb();
 102                 ltd->link = cpu_to_le32(td->dma_handle);
 103         } else {
 104                 td->link = uhci->fl->frame[framenum];
 105                 wmb();
 106                 uhci->fl->frame[framenum] = cpu_to_le32(td->dma_handle);
 107                 uhci->fl->frame_cpu[framenum] = td;
 108         }
 109 }
 110
 111 static void uhci_remove_td(struct uhci_hcd *uhci, struct uhci_td *td)
 112 {
 113         /* If it's not inserted, don't remove it */
 114         if (td->frame == -1 && list_empty(&td->fl_list))
 115                 return;
 116
 117         if (td->frame != -1 && uhci->fl->frame_cpu[td->frame] == td) {
 118                 if (list_empty(&td->fl_list)) {
 119                         uhci->fl->frame[td->frame] = td->link;
 120                         uhci->fl->frame_cpu[td->frame] = NULL;
 121                 } else {
 122                         struct uhci_td *ntd;
 123
 124                         ntd = list_entry(td->fl_list.next, struct uhci_td, fl_list);
 125                         uhci->fl->frame[td->frame] = cpu_to_le32(ntd->dma_handle);
 126                         uhci->fl->frame_cpu[td->frame] = ntd;
 127                 }
 128         } else {
 129                 struct uhci_td *ptd;
 130
 131                 ptd = list_entry(td->fl_list.prev, struct uhci_td, fl_list);
 132                 ptd->link = td->link;
 133         }
 134
 135         wmb();
 136         td->link = UHCI_PTR_TERM;
 137
 138         list_del_init(&td->fl_list);
 139         td->frame = -1;
 140 }
 141
 142 /*
 143  * Inserts a td list into qh.
 144  */
 145 static void uhci_insert_tds_in_qh(struct uhci_qh *qh, struct urb *urb, __le32 breadth)
 146 {
 147         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 148         struct uhci_td *td;
 149         __le32 *plink;
 150
 151         /* Ordering isn't important here yet since the QH hasn't been */
 152         /* inserted into the schedule yet */
 153         plink = &qh->element;
 154         list_for_each_entry(td, &urbp->td_list, list) {
 155                 *plink = cpu_to_le32(td->dma_handle) | breadth;
 156                 plink = &td->link;
 157         }
 158         *plink = UHCI_PTR_TERM;
 159 }
 160
 161 static void uhci_free_td(struct uhci_hcd *uhci, struct uhci_td *td)
 162 {
 163         if (!list_empty(&td->list))
 164                 dev_warn(uhci_dev(uhci), "td %p still in list!\n", td);
 165         if (!list_empty(&td->remove_list))
 166                 dev_warn(uhci_dev(uhci), "td %p still in remove_list!\n", td);
 167         if (!list_empty(&td->fl_list))
 168                 dev_warn(uhci_dev(uhci), "td %p still in fl_list!\n", td);
 169
 170         dma_pool_free(uhci->td_pool, td, td->dma_handle);
 171 }
 172
 173 static struct uhci_qh *uhci_alloc_qh(struct uhci_hcd *uhci)
 174 {
 175         dma_addr_t dma_handle;
 176         struct uhci_qh *qh;
 177
 178         qh = dma_pool_alloc(uhci->qh_pool, GFP_ATOMIC, &dma_handle);
 179         if (!qh)
 180                 return NULL;
 181
 182         qh->dma_handle = dma_handle;
 183
 184         qh->element = UHCI_PTR_TERM;
 185         qh->link = UHCI_PTR_TERM;
 186
 187         qh->urbp = NULL;
 188
 189         INIT_LIST_HEAD(&qh->list);
 190         INIT_LIST_HEAD(&qh->remove_list);
 191
 192         return qh;
 193 }
 194
 195 static void uhci_free_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
 196 {
 197         if (!list_empty(&qh->list))
 198                 dev_warn(uhci_dev(uhci), "qh %p list not empty!\n", qh);
 199         if (!list_empty(&qh->remove_list))
 200                 dev_warn(uhci_dev(uhci), "qh %p still in remove_list!\n", qh);
 201
 202         dma_pool_free(uhci->qh_pool, qh, qh->dma_handle);
 203 }
 204
 205 /*
 206  * Append this urb's qh after the last qh in skelqh->list
 207  *
 208  * Note that urb_priv.queue_list doesn't have a separate queue head;
 209  * it's a ring with every element "live".
 210  */
 211 static void uhci_insert_qh(struct uhci_hcd *uhci, struct uhci_qh *skelqh, struct urb *urb)
 212 {
 213         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 214         struct urb_priv *turbp;
 215         struct uhci_qh *lqh;
 216
 217         /* Grab the last QH */
 218         lqh = list_entry(skelqh->list.prev, struct uhci_qh, list);
 219
 220         /* Point to the next skelqh */
 221         urbp->qh->link = lqh->link;
 222         wmb();                          /* Ordering is important */
 223
 224         /*
 225          * Patch QHs for previous endpoint's queued URBs?  HC goes
 226          * here next, not to the next skelqh it now points to.
 227          *
 228          *    lqh --> td ... --> qh ... --> td --> qh ... --> td
 229          *     |                 |                 |
 230          *     v                 v                 v
 231          *     +<----------------+-----------------+
 232          *     v
 233          *    newqh --> td ... --> td
 234          *     |
 235          *     v
 236          *    ...
 237          *
 238          * The HC could see (and use!) any of these as we write them.
 239          */
 240         lqh->link = cpu_to_le32(urbp->qh->dma_handle) | UHCI_PTR_QH;
 241         if (lqh->urbp) {
 242                 list_for_each_entry(turbp, &lqh->urbp->queue_list, queue_list)
 243                         turbp->qh->link = lqh->link;
 244         }
 245
 246         list_add_tail(&urbp->qh->list, &skelqh->list);
 247 }
 248
 249 /*
 250  * Start removal of QH from schedule; it finishes next frame.
 251  * TDs should be unlinked before this is called.
 252  */
 253 static void uhci_remove_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
 254 {
 255         struct uhci_qh *pqh;
 256         __le32 newlink;
 257
 258         if (!qh)
 259                 return;
 260
 261         /*
 262          * Only go through the hoops if it's actually linked in
 263          */
 264         if (!list_empty(&qh->list)) {
 265
 266                 /* If our queue is nonempty, make the next URB the head */
 267                 if (!list_empty(&qh->urbp->queue_list)) {
 268                         struct urb_priv *nurbp;
 269
 270                         nurbp = list_entry(qh->urbp->queue_list.next,
 271                                         struct urb_priv, queue_list);
 272                         nurbp->queued = 0;
 273                         list_add(&nurbp->qh->list, &qh->list);
 274                         newlink = cpu_to_le32(nurbp->qh->dma_handle) | UHCI_PTR_QH;
 275                 } else
 276                         newlink = qh->link;
 277
 278                 /* Fix up the previous QH's queue to link to either
 279                  * the new head of this queue or the start of the
 280                  * next endpoint's queue. */
 281                 pqh = list_entry(qh->list.prev, struct uhci_qh, list);
 282                 pqh->link = newlink;
 283                 if (pqh->urbp) {
 284                         struct urb_priv *turbp;
 285
 286                         list_for_each_entry(turbp, &pqh->urbp->queue_list,
 287                                         queue_list)
 288                                 turbp->qh->link = newlink;
 289                 }
 290                 wmb();
 291
 292                 /* Leave qh->link in case the HC is on the QH now, it will */
 293                 /* continue the rest of the schedule */
 294                 qh->element = UHCI_PTR_TERM;
 295
 296                 list_del_init(&qh->list);
 297         }
 298
 299         list_del_init(&qh->urbp->queue_list);
 300         qh->urbp = NULL;
 301
 302         uhci_get_current_frame_number(uhci);
 303         if (uhci->frame_number + uhci->is_stopped != uhci->qh_remove_age) {
 304                 uhci_free_pending_qhs(uhci);
 305                 uhci->qh_remove_age = uhci->frame_number;
 306         }
 307
 308         /* Check to see if the remove list is empty. Set the IOC bit */
 309         /* to force an interrupt so we can remove the QH */
 310         if (list_empty(&uhci->qh_remove_list))
 311                 uhci_set_next_interrupt(uhci);
 312
 313         list_add(&qh->remove_list, &uhci->qh_remove_list);
 314 }
 315
 316 static int uhci_fixup_toggle(struct urb *urb, unsigned int toggle)
 317 {
 318         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 319         struct uhci_td *td;
 320
 321         list_for_each_entry(td, &urbp->td_list, list) {
 322                 if (toggle)
 323                         td->token |= cpu_to_le32(TD_TOKEN_TOGGLE);
 324                 else
 325                         td->token &= ~cpu_to_le32(TD_TOKEN_TOGGLE);
 326
 327                 toggle ^= 1;
 328         }
 329
 330         return toggle;
 331 }
 332
 333 /* This function will append one URB's QH to another URB's QH. This is for */
 334 /* queuing interrupt, control or bulk transfers */
 335 static void uhci_append_queued_urb(struct uhci_hcd *uhci, struct urb *eurb, struct urb *urb)
 336 {
 337         struct urb_priv *eurbp, *urbp, *furbp, *lurbp;
 338         struct uhci_td *lltd;
 339
 340         eurbp = eurb->hcpriv;
 341         urbp = urb->hcpriv;
 342
 343         /* Find the first URB in the queue */
 344         furbp = eurbp;
 345         if (eurbp->queued) {
 346                 list_for_each_entry(furbp, &eurbp->queue_list, queue_list)
 347                         if (!furbp->queued)
 348                                 break;
 349         }
 350
 351         lurbp = list_entry(furbp->queue_list.prev, struct urb_priv, queue_list);
 352
 353         lltd = list_entry(lurbp->td_list.prev, struct uhci_td, list);
 354
 355         /* Control transfers always start with toggle 0 */
 356         if (!usb_pipecontrol(urb->pipe))
 357                 usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
 358                                 usb_pipeout(urb->pipe),
 359                                 uhci_fixup_toggle(urb,
 360                                         uhci_toggle(td_token(lltd)) ^ 1));
 361
 362         /* All qh's in the queue need to link to the next queue */
 363         urbp->qh->link = eurbp->qh->link;
 364
 365         wmb();                  /* Make sure we flush everything */
 366
 367         lltd->link = cpu_to_le32(urbp->qh->dma_handle) | UHCI_PTR_QH;
 368
 369         list_add_tail(&urbp->queue_list, &furbp->queue_list);
 370
 371         urbp->queued = 1;
 372 }
 373
 374 static void uhci_delete_queued_urb(struct uhci_hcd *uhci, struct urb *urb)
 375 {
 376         struct urb_priv *urbp, *nurbp, *purbp, *turbp;
 377         struct uhci_td *pltd;
 378         unsigned int toggle;
 379
 380         urbp = urb->hcpriv;
 381
 382         if (list_empty(&urbp->queue_list))
 383                 return;
 384
 385         nurbp = list_entry(urbp->queue_list.next, struct urb_priv, queue_list);
 386
 387         /*
 388          * Fix up the toggle for the following URBs in the queue.
 389          * Only needed for bulk and interrupt: control and isochronous
 390          * endpoints don't propagate toggles between messages.
 391          */
 392         if (usb_pipebulk(urb->pipe) || usb_pipeint(urb->pipe)) {
 393                 if (!urbp->queued)
 394                         /* We just set the toggle in uhci_unlink_generic */
 395                         toggle = usb_gettoggle(urb->dev,
 396                                         usb_pipeendpoint(urb->pipe),
 397                                         usb_pipeout(urb->pipe));
 398                 else {
 399                         /* If we're in the middle of the queue, grab the */
 400                         /* toggle from the TD previous to us */
 401                         purbp = list_entry(urbp->queue_list.prev,
 402                                         struct urb_priv, queue_list);
 403                         pltd = list_entry(purbp->td_list.prev,
 404                                         struct uhci_td, list);
 405                         toggle = uhci_toggle(td_token(pltd)) ^ 1;
 406                 }
 407
 408                 list_for_each_entry(turbp, &urbp->queue_list, queue_list) {
 409                         if (!turbp->queued)
 410                                 break;
 411                         toggle = uhci_fixup_toggle(turbp->urb, toggle);
 412                 }
 413
 414                 usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
 415                                 usb_pipeout(urb->pipe), toggle);
 416         }
 417
 418         if (urbp->queued) {
 419                 /* We're somewhere in the middle (or end).  The case where
 420                  * we're at the head is handled in uhci_remove_qh(). */
 421                 purbp = list_entry(urbp->queue_list.prev, struct urb_priv,
 422                                 queue_list);
 423
 424                 pltd = list_entry(purbp->td_list.prev, struct uhci_td, list);
 425                 if (nurbp->queued)
 426                         pltd->link = cpu_to_le32(nurbp->qh->dma_handle) | UHCI_PTR_QH;
 427                 else
 428                         /* The next URB happens to be the beginning, so */
 429                         /*  we're the last, end the chain */
 430                         pltd->link = UHCI_PTR_TERM;
 431         }
 432
 433         /* urbp->queue_list is handled in uhci_remove_qh() */
 434 }
 435
 436 static struct urb_priv *uhci_alloc_urb_priv(struct uhci_hcd *uhci, struct urb *urb)
 437 {
 438         struct urb_priv *urbp;
 439
 440         urbp = kmem_cache_alloc(uhci_up_cachep, SLAB_ATOMIC);
 441         if (!urbp)
 442                 return NULL;
 443
 444         memset((void *)urbp, 0, sizeof(*urbp));
 445
 446         urbp->inserttime = jiffies;
 447         urbp->fsbrtime = jiffies;
 448         urbp->urb = urb;
 449
 450         INIT_LIST_HEAD(&urbp->td_list);
 451         INIT_LIST_HEAD(&urbp->queue_list);
 452         INIT_LIST_HEAD(&urbp->urb_list);
 453
 454         list_add_tail(&urbp->urb_list, &uhci->urb_list);
 455
 456         urb->hcpriv = urbp;
 457
 458         return urbp;
 459 }
 460
 461 static void uhci_add_td_to_urb(struct urb *urb, struct uhci_td *td)
 462 {
 463         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 464
 465         td->urb = urb;
 466
 467         list_add_tail(&td->list, &urbp->td_list);
 468 }
 469
 470 static void uhci_remove_td_from_urb(struct uhci_td *td)
 471 {
 472         if (list_empty(&td->list))
 473                 return;
 474
 475         list_del_init(&td->list);
 476
 477         td->urb = NULL;
 478 }
 479
 480 static void uhci_destroy_urb_priv(struct uhci_hcd *uhci, struct urb *urb)
 481 {
 482         struct uhci_td *td, *tmp;
 483         struct urb_priv *urbp;
 484
 485         urbp = (struct urb_priv *)urb->hcpriv;
 486         if (!urbp)
 487                 return;
 488
 489         if (!list_empty(&urbp->urb_list))
 490                 dev_warn(uhci_dev(uhci), "urb %p still on uhci->urb_list "
 491                                 "or uhci->remove_list!\n", urb);
 492
 493         uhci_get_current_frame_number(uhci);
 494         if (uhci->frame_number + uhci->is_stopped != uhci->td_remove_age) {
 495                 uhci_free_pending_tds(uhci);
 496                 uhci->td_remove_age = uhci->frame_number;
 497         }
 498
 499         /* Check to see if the remove list is empty. Set the IOC bit */
 500         /* to force an interrupt so we can remove the TD's*/
 501         if (list_empty(&uhci->td_remove_list))
 502                 uhci_set_next_interrupt(uhci);
 503
 504         list_for_each_entry_safe(td, tmp, &urbp->td_list, list) {
 505                 uhci_remove_td_from_urb(td);
 506                 uhci_remove_td(uhci, td);
 507                 list_add(&td->remove_list, &uhci->td_remove_list);
 508         }
 509
 510         urb->hcpriv = NULL;
 511         kmem_cache_free(uhci_up_cachep, urbp);
 512 }
 513
 514 static void uhci_inc_fsbr(struct uhci_hcd *uhci, struct urb *urb)
 515 {
 516         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 517
 518         if ((!(urb->transfer_flags & URB_NO_FSBR)) && !urbp->fsbr) {
 519                 urbp->fsbr = 1;
 520                 if (!uhci->fsbr++ && !uhci->fsbrtimeout)
 521                         uhci->skel_term_qh->link = cpu_to_le32(uhci->skel_fs_control_qh->dma_handle) | UHCI_PTR_QH;
 522         }
 523 }
 524
 525 static void uhci_dec_fsbr(struct uhci_hcd *uhci, struct urb *urb)
 526 {
 527         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 528
 529         if ((!(urb->transfer_flags & URB_NO_FSBR)) && urbp->fsbr) {
 530                 urbp->fsbr = 0;
 531                 if (!--uhci->fsbr)
 532                         uhci->fsbrtimeout = jiffies + FSBR_DELAY;
 533         }
 534 }
 535
 536 /*
 537  * Map status to standard result codes
 538  *
 539  * <status> is (td_status(td) & 0xF60000), a.k.a.
 540  * uhci_status_bits(td_status(td)).
 541  * Note: <status> does not include the TD_CTRL_NAK bit.
 542  * <dir_out> is True for output TDs and False for input TDs.
 543  */
 544 static int uhci_map_status(int status, int dir_out)
 545 {
 546         if (!status)
 547                 return 0;
 548         if (status & TD_CTRL_BITSTUFF)                  /* Bitstuff error */
 549                 return -EPROTO;
 550         if (status & TD_CTRL_CRCTIMEO) {                /* CRC/Timeout */
 551                 if (dir_out)
 552                         return -EPROTO;
 553                 else
 554                         return -EILSEQ;
 555         }
 556         if (status & TD_CTRL_BABBLE)                    /* Babble */
 557                 return -EOVERFLOW;
 558         if (status & TD_CTRL_DBUFERR)                   /* Buffer error */
 559                 return -ENOSR;
 560         if (status & TD_CTRL_STALLED)                   /* Stalled */
 561                 return -EPIPE;
 562         WARN_ON(status & TD_CTRL_ACTIVE);               /* Active */
 563         return 0;
 564 }
 565
 566 /*
 567  * Control transfers
 568  */
 569 static int uhci_submit_control(struct uhci_hcd *uhci, struct urb *urb, struct urb *eurb)
 570 {
 571         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 572         struct uhci_td *td;
 573         struct uhci_qh *qh, *skelqh;
 574         unsigned long destination, status;
 575         int maxsze = usb_maxpacket(urb->dev, urb->pipe, usb_pipeout(urb->pipe));
 576         int len = urb->transfer_buffer_length;
 577         dma_addr_t data = urb->transfer_dma;
 578
 579         /* The "pipe" thing contains the destination in bits 8--18 */
 580         destination = (urb->pipe & PIPE_DEVEP_MASK) | USB_PID_SETUP;
 581
 582         /* 3 errors */
 583         status = TD_CTRL_ACTIVE | uhci_maxerr(3);
 584         if (urb->dev->speed == USB_SPEED_LOW)
 585                 status |= TD_CTRL_LS;
 586
 587         /*
 588          * Build the TD for the control request setup packet
 589          */
 590         td = uhci_alloc_td(uhci);
 591         if (!td)
 592                 return -ENOMEM;
 593
 594         uhci_add_td_to_urb(urb, td);
 595         uhci_fill_td(td, status, destination | uhci_explen(7),
 596                 urb->setup_dma);
 597
 598         /*
 599          * If direction is "send", change the packet ID from SETUP (0x2D)
 600          * to OUT (0xE1).  Else change it from SETUP to IN (0x69) and
 601          * set Short Packet Detect (SPD) for all data packets.
 602          */
 603         if (usb_pipeout(urb->pipe))
 604                 destination ^= (USB_PID_SETUP ^ USB_PID_OUT);
 605         else {
 606                 destination ^= (USB_PID_SETUP ^ USB_PID_IN);
 607                 status |= TD_CTRL_SPD;
 608         }
 609
 610         /*
 611          * Build the DATA TD's
 612          */
 613         while (len > 0) {
 614                 int pktsze = len;
 615
 616                 if (pktsze > maxsze)
 617                         pktsze = maxsze;
 618
 619                 td = uhci_alloc_td(uhci);
 620                 if (!td)
 621                         return -ENOMEM;
 622
 623                 /* Alternate Data0/1 (start with Data1) */
 624                 destination ^= TD_TOKEN_TOGGLE;
 625
 626                 uhci_add_td_to_urb(urb, td);
 627                 uhci_fill_td(td, status, destination | uhci_explen(pktsze - 1),
 628                         data);
 629
 630                 data += pktsze;
 631                 len -= pktsze;
 632         }
 633
 634         /*
 635          * Build the final TD for control status
 636          */
 637         td = uhci_alloc_td(uhci);
 638         if (!td)
 639                 return -ENOMEM;
 640
 641         /*
 642          * It's IN if the pipe is an output pipe or we're not expecting
 643          * data back.
 644          */
 645         destination &= ~TD_TOKEN_PID_MASK;
 646         if (usb_pipeout(urb->pipe) || !urb->transfer_buffer_length)
 647                 destination |= USB_PID_IN;
 648         else
 649                 destination |= USB_PID_OUT;
 650
 651         destination |= TD_TOKEN_TOGGLE;         /* End in Data1 */
 652
 653         status &= ~TD_CTRL_SPD;
 654
 655         uhci_add_td_to_urb(urb, td);
 656         uhci_fill_td(td, status | TD_CTRL_IOC,
 657                 destination | uhci_explen(UHCI_NULL_DATA_SIZE), 0);
 658
 659         qh = uhci_alloc_qh(uhci);
 660         if (!qh)
 661                 return -ENOMEM;
 662
 663         urbp->qh = qh;
 664         qh->urbp = urbp;
 665
 666         uhci_insert_tds_in_qh(qh, urb, UHCI_PTR_BREADTH);
 667
 668         /* Low-speed transfers get a different queue, and won't hog the bus.
 669          * Also, some devices enumerate better without FSBR; the easiest way
 670          * to do that is to put URBs on the low-speed queue while the device
 671          * is in the DEFAULT state. */
 672         if (urb->dev->speed == USB_SPEED_LOW ||
 673                         urb->dev->state == USB_STATE_DEFAULT)
 674                 skelqh = uhci->skel_ls_control_qh;
 675         else {
 676                 skelqh = uhci->skel_fs_control_qh;
 677                 uhci_inc_fsbr(uhci, urb);
 678         }
 679
 680         if (eurb)
 681                 uhci_append_queued_urb(uhci, eurb, urb);
 682         else
 683                 uhci_insert_qh(uhci, skelqh, urb);
 684
 685         return -EINPROGRESS;
 686 }
 687
 688 /*
 689  * If control-IN transfer was short, the status packet wasn't sent.
 690  * This routine changes the element pointer in the QH to point at the
 691  * status TD.  It's safe to do this even while the QH is live, because
 692  * the hardware only updates the element pointer following a successful
 693  * transfer.  The inactive TD for the short packet won't cause an update,
 694  * so the pointer won't get overwritten.  The next time the controller
 695  * sees this QH, it will send the status packet.
 696  */
 697 static int usb_control_retrigger_status(struct uhci_hcd *uhci, struct urb *urb)
 698 {
 699         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 700         struct uhci_td *td;
 701
 702         urbp->short_control_packet = 1;
 703
 704         td = list_entry(urbp->td_list.prev, struct uhci_td, list);
 705         urbp->qh->element = cpu_to_le32(td->dma_handle);
 706
 707         return -EINPROGRESS;
 708 }
 709
 710
 711 static int uhci_result_control(struct uhci_hcd *uhci, struct urb *urb)
 712 {
 713         struct list_head *tmp, *head;
 714         struct urb_priv *urbp = urb->hcpriv;
 715         struct uhci_td *td;
 716         unsigned int status;
 717         int ret = 0;
 718
 719         if (list_empty(&urbp->td_list))
 720                 return -EINVAL;
 721
 722         head = &urbp->td_list;
 723
 724         if (urbp->short_control_packet) {
 725                 tmp = head->prev;
 726                 goto status_stage;
 727         }
 728
 729         tmp = head->next;
 730         td = list_entry(tmp, struct uhci_td, list);
 731
 732         /* The first TD is the SETUP stage, check the status, but skip */
 733         /*  the count */
 734         status = uhci_status_bits(td_status(td));
 735         if (status & TD_CTRL_ACTIVE)
 736                 return -EINPROGRESS;
 737
 738         if (status)
 739                 goto td_error;
 740
 741         urb->actual_length = 0;
 742
 743         /* The rest of the TD's (but the last) are data */
 744         tmp = tmp->next;
 745         while (tmp != head && tmp->next != head) {
 746                 unsigned int ctrlstat;
 747
 748                 td = list_entry(tmp, struct uhci_td, list);
 749                 tmp = tmp->next;
 750
 751                 ctrlstat = td_status(td);
 752                 status = uhci_status_bits(ctrlstat);
 753                 if (status & TD_CTRL_ACTIVE)
 754                         return -EINPROGRESS;
 755
 756                 urb->actual_length += uhci_actual_length(ctrlstat);
 757
 758                 if (status)
 759                         goto td_error;
 760
 761                 /* Check to see if we received a short packet */
 762                 if (uhci_actual_length(ctrlstat) <
 763                                 uhci_expected_length(td_token(td))) {
 764                         if (urb->transfer_flags & URB_SHORT_NOT_OK) {
 765                                 ret = -EREMOTEIO;
 766                                 goto err;
 767                         }
 768
 769                         if (uhci_packetid(td_token(td)) == USB_PID_IN)
 770                                 return usb_control_retrigger_status(uhci, urb);
 771                         else
 772                                 return 0;
 773                 }
 774         }
 775
 776 status_stage:
 777         td = list_entry(tmp, struct uhci_td, list);
 778
 779         /* Control status stage */
 780         status = td_status(td);
 781
 782 #ifdef I_HAVE_BUGGY_APC_BACKUPS
 783         /* APC BackUPS Pro kludge */
 784         /* It tries to send all of the descriptor instead of the amount */
 785         /*  we requested */
 786         if (status & TD_CTRL_IOC &&     /* IOC is masked out by uhci_status_bits */
 787             status & TD_CTRL_ACTIVE &&
 788             status & TD_CTRL_NAK)
 789                 return 0;
 790 #endif
 791
 792         status = uhci_status_bits(status);
 793         if (status & TD_CTRL_ACTIVE)
 794                 return -EINPROGRESS;
 795
 796         if (status)
 797                 goto td_error;
 798
 799         return 0;
 800
 801 td_error:
 802         ret = uhci_map_status(status, uhci_packetout(td_token(td)));
 803
 804 err:
 805         if ((debug == 1 && ret != -EPIPE) || debug > 1) {
 806                 /* Some debugging code */
 807                 dev_dbg(uhci_dev(uhci), "%s: failed with status %x\n",
 808                                 __FUNCTION__, status);
 809
 810                 if (errbuf) {
 811                         /* Print the chain for debugging purposes */
 812                         uhci_show_qh(urbp->qh, errbuf, ERRBUF_LEN, 0);
 813
 814                         lprintk(errbuf);
 815                 }
 816         }
 817
 818         return ret;
 819 }
 820
 821 /*
 822  * Common submit for bulk and interrupt
 823  */
 824 static int uhci_submit_common(struct uhci_hcd *uhci, struct urb *urb, struct urb *eurb, struct uhci_qh *skelqh)
 825 {
 826         struct uhci_td *td;
 827         struct uhci_qh *qh;
 828         unsigned long destination, status;
 829         int maxsze = usb_maxpacket(urb->dev, urb->pipe, usb_pipeout(urb->pipe));
 830         int len = urb->transfer_buffer_length;
 831         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
 832         dma_addr_t data = urb->transfer_dma;
 833
 834         if (len < 0)
 835                 return -EINVAL;
 836
 837         /* The "pipe" thing contains the destination in bits 8--18 */
 838         destination = (urb->pipe & PIPE_DEVEP_MASK) | usb_packetid(urb->pipe);
 839
 840         status = uhci_maxerr(3) | TD_CTRL_ACTIVE;
 841         if (urb->dev->speed == USB_SPEED_LOW)
 842                 status |= TD_CTRL_LS;
 843         if (usb_pipein(urb->pipe))
 844                 status |= TD_CTRL_SPD;
 845
 846         /*
 847          * Build the DATA TD's
 848          */
 849         do {    /* Allow zero length packets */
 850                 int pktsze = maxsze;
 851
 852                 if (pktsze >= len) {
 853                         pktsze = len;
 854                         if (!(urb->transfer_flags & URB_SHORT_NOT_OK))
 855                                 status &= ~TD_CTRL_SPD;
 856                 }
 857
 858                 td = uhci_alloc_td(uhci);
 859                 if (!td)
 860                         return -ENOMEM;
 861
 862                 uhci_add_td_to_urb(urb, td);
 863                 uhci_fill_td(td, status, destination | uhci_explen(pktsze - 1) |
 864                         (usb_gettoggle(urb->dev, usb_pipeendpoint(urb->pipe),
 865                          usb_pipeout(urb->pipe)) << TD_TOKEN_TOGGLE_SHIFT),
 866                         data);
 867
 868                 data += pktsze;
 869                 len -= maxsze;
 870
 871                 usb_dotoggle(urb->dev, usb_pipeendpoint(urb->pipe),
 872                         usb_pipeout(urb->pipe));
 873         } while (len > 0);
 874
 875         /*
 876          * URB_ZERO_PACKET means adding a 0-length packet, if direction
 877          * is OUT and the transfer_length was an exact multiple of maxsze,
 878          * hence (len = transfer_length - N * maxsze) == 0
 879          * however, if transfer_length == 0, the zero packet was already
 880          * prepared above.
 881          */
 882         if (usb_pipeout(urb->pipe) && (urb->transfer_flags & URB_ZERO_PACKET) &&
 883             !len && urb->transfer_buffer_length) {
 884                 td = uhci_alloc_td(uhci);
 885                 if (!td)
 886                         return -ENOMEM;
 887
 888                 uhci_add_td_to_urb(urb, td);
 889                 uhci_fill_td(td, status, destination | uhci_explen(UHCI_NULL_DATA_SIZE) |
 890                         (usb_gettoggle(urb->dev, usb_pipeendpoint(urb->pipe),
 891                          usb_pipeout(urb->pipe)) << TD_TOKEN_TOGGLE_SHIFT),
 892                         data);
 893
 894                 usb_dotoggle(urb->dev, usb_pipeendpoint(urb->pipe),
 895                         usb_pipeout(urb->pipe));
 896         }
 897
 898         /* Set the interrupt-on-completion flag on the last packet.
 899          * A more-or-less typical 4 KB URB (= size of one memory page)
 900          * will require about 3 ms to transfer; that's a little on the
 901          * fast side but not enough to justify delaying an interrupt
 902          * more than 2 or 3 URBs, so we will ignore the URB_NO_INTERRUPT
 903          * flag setting. */
 904         td->status |= cpu_to_le32(TD_CTRL_IOC);
 905
 906         qh = uhci_alloc_qh(uhci);
 907         if (!qh)
 908                 return -ENOMEM;
 909
 910         urbp->qh = qh;
 911         qh->urbp = urbp;
 912
 913         /* Always breadth first */
 914         uhci_insert_tds_in_qh(qh, urb, UHCI_PTR_BREADTH);
 915
 916         if (eurb)
 917                 uhci_append_queued_urb(uhci, eurb, urb);
 918         else
 919                 uhci_insert_qh(uhci, skelqh, urb);
 920
 921         return -EINPROGRESS;
 922 }
 923
 924 /*
 925  * Common result for bulk and interrupt
 926  */
 927 static int uhci_result_common(struct uhci_hcd *uhci, struct urb *urb)
 928 {
 929         struct urb_priv *urbp = urb->hcpriv;
 930         struct uhci_td *td;
 931         unsigned int status = 0;
 932         int ret = 0;
 933
 934         urb->actual_length = 0;
 935
 936         list_for_each_entry(td, &urbp->td_list, list) {
 937                 unsigned int ctrlstat = td_status(td);
 938
 939                 status = uhci_status_bits(ctrlstat);
 940                 if (status & TD_CTRL_ACTIVE)
 941                         return -EINPROGRESS;
 942
 943                 urb->actual_length += uhci_actual_length(ctrlstat);
 944
 945                 if (status)
 946                         goto td_error;
 947
 948                 if (uhci_actual_length(ctrlstat) <
 949                                 uhci_expected_length(td_token(td))) {
 950                         if (urb->transfer_flags & URB_SHORT_NOT_OK) {
 951                                 ret = -EREMOTEIO;
 952                                 goto err;
 953                         } else
 954                                 return 0;
 955                 }
 956         }
 957
 958         return 0;
 959
 960 td_error:
 961         ret = uhci_map_status(status, uhci_packetout(td_token(td)));
 962
 963 err:
 964         /*
 965          * Enable this chunk of code if you want to see some more debugging.
 966          * But be careful, it has the tendancy to starve out khubd and prevent
 967          * disconnects from happening successfully if you have a slow debug
 968          * log interface (like a serial console.
 969          */
 970 #if 0
 971         if ((debug == 1 && ret != -EPIPE) || debug > 1) {
 972                 /* Some debugging code */
 973                 dev_dbg(uhci_dev(uhci), "%s: failed with status %x\n",
 974                                 __FUNCTION__, status);
 975
 976                 if (errbuf) {
 977                         /* Print the chain for debugging purposes */
 978                         uhci_show_qh(urbp->qh, errbuf, ERRBUF_LEN, 0);
 979
 980                         lprintk(errbuf);
 981                 }
 982         }
 983 #endif
 984         return ret;
 985 }
 986
 987 static inline int uhci_submit_bulk(struct uhci_hcd *uhci, struct urb *urb, struct urb *eurb)
 988 {
 989         int ret;
 990
 991         /* Can't have low-speed bulk transfers */
 992         if (urb->dev->speed == USB_SPEED_LOW)
 993                 return -EINVAL;
 994
 995         ret = uhci_submit_common(uhci, urb, eurb, uhci->skel_bulk_qh);
 996         if (ret == -EINPROGRESS)
 997                 uhci_inc_fsbr(uhci, urb);
 998
 999         return ret;
1000 }
1001
1002 static inline int uhci_submit_interrupt(struct uhci_hcd *uhci, struct urb *urb, struct urb *eurb)
1003 {
1004         /* USB 1.1 interrupt transfers only involve one packet per interval;
1005          * that's the uhci_submit_common() "breadth first" policy.  Drivers
1006          * can submit urbs of any length, but longer ones might need many
1007          * intervals to complete.
1008          */
1009         return uhci_submit_common(uhci, urb, eurb, uhci->skelqh[__interval_to_skel(urb->interval)]);
1010 }
1011
1012 /*
1013  * Isochronous transfers
1014  */
1015 static int isochronous_find_limits(struct uhci_hcd *uhci, struct urb *urb, unsigned int *start, unsigned int *end)
1016 {
1017         struct urb *last_urb = NULL;
1018         struct urb_priv *up;
1019         int ret = 0;
1020
1021         list_for_each_entry(up, &uhci->urb_list, urb_list) {
1022                 struct urb *u = up->urb;
1023
1024                 /* look for pending URB's with identical pipe handle */
1025                 if ((urb->pipe == u->pipe) && (urb->dev == u->dev) &&
1026                     (u->status == -EINPROGRESS) && (u != urb)) {
1027                         if (!last_urb)
1028                                 *start = u->start_frame;
1029                         last_urb = u;
1030                 }
1031         }
1032
1033         if (last_urb) {
1034                 *end = (last_urb->start_frame + last_urb->number_of_packets *
1035                                 last_urb->interval) & (UHCI_NUMFRAMES-1);
1036                 ret = 0;
1037         } else
1038                 ret = -1;       /* no previous urb found */
1039
1040         return ret;
1041 }
1042
1043 static int isochronous_find_start(struct uhci_hcd *uhci, struct urb *urb)
1044 {
1045         int limits;
1046         unsigned int start = 0, end = 0;
1047
1048         if (urb->number_of_packets > 900)       /* 900? Why? */
1049                 return -EFBIG;
1050
1051         limits = isochronous_find_limits(uhci, urb, &start, &end);
1052
1053         if (urb->transfer_flags & URB_ISO_ASAP) {
1054                 if (limits) {
1055                         uhci_get_current_frame_number(uhci);
1056                         urb->start_frame = (uhci->frame_number + 10)
1057                                         & (UHCI_NUMFRAMES - 1);
1058                 } else
1059                         urb->start_frame = end;
1060         } else {
1061                 urb->start_frame &= (UHCI_NUMFRAMES - 1);
1062                 /* FIXME: Sanity check */
1063         }
1064
1065         return 0;
1066 }
1067
1068 /*
1069  * Isochronous transfers
1070  */
1071 static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb)
1072 {
1073         struct uhci_td *td;
1074         int i, ret, frame;
1075         int status, destination;
1076
1077         status = TD_CTRL_ACTIVE | TD_CTRL_IOS;
1078         destination = (urb->pipe & PIPE_DEVEP_MASK) | usb_packetid(urb->pipe);
1079
1080         ret = isochronous_find_start(uhci, urb);
1081         if (ret)
1082                 return ret;
1083
1084         frame = urb->start_frame;
1085         for (i = 0; i < urb->number_of_packets; i++, frame += urb->interval) {
1086                 if (!urb->iso_frame_desc[i].length)
1087                         continue;
1088
1089                 td = uhci_alloc_td(uhci);
1090                 if (!td)
1091                         return -ENOMEM;
1092
1093                 uhci_add_td_to_urb(urb, td);
1094                 uhci_fill_td(td, status, destination | uhci_explen(urb->iso_frame_desc[i].length - 1),
1095                         urb->transfer_dma + urb->iso_frame_desc[i].offset);
1096
1097                 if (i + 1 >= urb->number_of_packets)
1098                         td->status |= cpu_to_le32(TD_CTRL_IOC);
1099
1100                 uhci_insert_td_frame_list(uhci, td, frame);
1101         }
1102
1103         return -EINPROGRESS;
1104 }
1105
1106 static int uhci_result_isochronous(struct uhci_hcd *uhci, struct urb *urb)
1107 {
1108         struct uhci_td *td;
1109         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
1110         int status;
1111         int i, ret = 0;
1112
1113         urb->actual_length = 0;
1114
1115         i = 0;
1116         list_for_each_entry(td, &urbp->td_list, list) {
1117                 int actlength;
1118                 unsigned int ctrlstat = td_status(td);
1119
1120                 if (ctrlstat & TD_CTRL_ACTIVE)
1121                         return -EINPROGRESS;
1122
1123                 actlength = uhci_actual_length(ctrlstat);
1124                 urb->iso_frame_desc[i].actual_length = actlength;
1125                 urb->actual_length += actlength;
1126
1127                 status = uhci_map_status(uhci_status_bits(ctrlstat),
1128                                 usb_pipeout(urb->pipe));
1129                 urb->iso_frame_desc[i].status = status;
1130                 if (status) {
1131                         urb->error_count++;
1132                         ret = status;
1133                 }
1134
1135                 i++;
1136         }
1137
1138         return ret;
1139 }
1140
1141 static struct urb *uhci_find_urb_ep(struct uhci_hcd *uhci, struct urb *urb)
1142 {
1143         struct urb_priv *up;
1144
1145         /* We don't match Isoc transfers since they are special */
1146         if (usb_pipeisoc(urb->pipe))
1147                 return NULL;
1148
1149         list_for_each_entry(up, &uhci->urb_list, urb_list) {
1150                 struct urb *u = up->urb;
1151
1152                 if (u->dev == urb->dev && u->status == -EINPROGRESS) {
1153                         /* For control, ignore the direction */
1154                         if (usb_pipecontrol(urb->pipe) &&
1155                             (u->pipe & ~USB_DIR_IN) == (urb->pipe & ~USB_DIR_IN))
1156                                 return u;
1157                         else if (u->pipe == urb->pipe)
1158                                 return u;
1159                 }
1160         }
1161
1162         return NULL;
1163 }
1164
1165 static int uhci_urb_enqueue(struct usb_hcd *hcd,
1166                 struct usb_host_endpoint *ep,
1167                 struct urb *urb, unsigned mem_flags)
1168 {
1169         int ret;
1170         struct uhci_hcd *uhci = hcd_to_uhci(hcd);
1171         unsigned long flags;
1172         struct urb *eurb;
1173         int bustime;
1174
1175         spin_lock_irqsave(&uhci->lock, flags);
1176
1177         ret = urb->status;
1178         if (ret != -EINPROGRESS)                /* URB already unlinked! */
1179                 goto out;
1180
1181         eurb = uhci_find_urb_ep(uhci, urb);
1182
1183         if (!uhci_alloc_urb_priv(uhci, urb)) {
1184                 ret = -ENOMEM;
1185                 goto out;
1186         }
1187
1188         switch (usb_pipetype(urb->pipe)) {
1189         case PIPE_CONTROL:
1190                 ret = uhci_submit_control(uhci, urb, eurb);
1191                 break;
1192         case PIPE_INTERRUPT:
1193                 if (!eurb) {
1194                         bustime = usb_check_bandwidth(urb->dev, urb);
1195                         if (bustime < 0)
1196                                 ret = bustime;
1197                         else {
1198                                 ret = uhci_submit_interrupt(uhci, urb, eurb);
1199                                 if (ret == -EINPROGRESS)
1200                                         usb_claim_bandwidth(urb->dev, urb, bustime, 0);
1201                         }
1202                 } else {        /* inherit from parent */
1203                         urb->bandwidth = eurb->bandwidth;
1204                         ret = uhci_submit_interrupt(uhci, urb, eurb);
1205                 }
1206                 break;
1207         case PIPE_BULK:
1208                 ret = uhci_submit_bulk(uhci, urb, eurb);
1209                 break;
1210         case PIPE_ISOCHRONOUS:
1211                 bustime = usb_check_bandwidth(urb->dev, urb);
1212                 if (bustime < 0) {
1213                         ret = bustime;
1214                         break;
1215                 }
1216
1217                 ret = uhci_submit_isochronous(uhci, urb);
1218                 if (ret == -EINPROGRESS)
1219                         usb_claim_bandwidth(urb->dev, urb, bustime, 1);
1220                 break;
1221         }
1222
1223         if (ret != -EINPROGRESS) {
1224                 /* Submit failed, so delete it from the urb_list */
1225                 struct urb_priv *urbp = urb->hcpriv;
1226
1227                 list_del_init(&urbp->urb_list);
1228                 uhci_destroy_urb_priv(uhci, urb);
1229         } else
1230                 ret = 0;
1231
1232 out:
1233         spin_unlock_irqrestore(&uhci->lock, flags);
1234         return ret;
1235 }
1236
1237 /*
1238  * Return the result of a transfer
1239  */
1240 static void uhci_transfer_result(struct uhci_hcd *uhci, struct urb *urb)
1241 {
1242         int ret = -EINPROGRESS;
1243         struct urb_priv *urbp;
1244
1245         spin_lock(&urb->lock);
1246
1247         urbp = (struct urb_priv *)urb->hcpriv;
1248
1249         if (urb->status != -EINPROGRESS)        /* URB already dequeued */
1250                 goto out;
1251
1252         switch (usb_pipetype(urb->pipe)) {
1253         case PIPE_CONTROL:
1254                 ret = uhci_result_control(uhci, urb);
1255                 break;
1256         case PIPE_BULK:
1257         case PIPE_INTERRUPT:
1258                 ret = uhci_result_common(uhci, urb);
1259                 break;
1260         case PIPE_ISOCHRONOUS:
1261                 ret = uhci_result_isochronous(uhci, urb);
1262                 break;
1263         }
1264
1265         if (ret == -EINPROGRESS)
1266                 goto out;
1267         urb->status = ret;
1268
1269         switch (usb_pipetype(urb->pipe)) {
1270         case PIPE_CONTROL:
1271         case PIPE_BULK:
1272         case PIPE_ISOCHRONOUS:
1273                 /* Release bandwidth for Interrupt or Isoc. transfers */
1274                 if (urb->bandwidth)
1275                         usb_release_bandwidth(urb->dev, urb, 1);
1276                 uhci_unlink_generic(uhci, urb);
1277                 break;
1278         case PIPE_INTERRUPT:
1279                 /* Release bandwidth for Interrupt or Isoc. transfers */
1280                 /* Make sure we don't release if we have a queued URB */
1281                 if (list_empty(&urbp->queue_list) && urb->bandwidth)
1282                         usb_release_bandwidth(urb->dev, urb, 0);
1283                 else
1284                         /* bandwidth was passed on to queued URB, */
1285                         /* so don't let usb_unlink_urb() release it */
1286                         urb->bandwidth = 0;
1287                 uhci_unlink_generic(uhci, urb);
1288                 break;
1289         default:
1290                 dev_info(uhci_dev(uhci), "%s: unknown pipe type %d "
1291                                 "for urb %p\n",
1292                                 __FUNCTION__, usb_pipetype(urb->pipe), urb);
1293         }
1294
1295         /* Move it from uhci->urb_list to uhci->complete_list */
1296         uhci_moveto_complete(uhci, urbp);
1297
1298 out:
1299         spin_unlock(&urb->lock);
1300 }
1301
1302 static void uhci_unlink_generic(struct uhci_hcd *uhci, struct urb *urb)
1303 {
1304         struct list_head *head;
1305         struct uhci_td *td;
1306         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
1307         int prevactive = 0;
1308
1309         uhci_dec_fsbr(uhci, urb);       /* Safe since it checks */
1310
1311         /*
1312          * Now we need to find out what the last successful toggle was
1313          * so we can update the local data toggle for the next transfer
1314          *
1315          * There are 2 ways the last successful completed TD is found:
1316          *
1317          * 1) The TD is NOT active and the actual length < expected length
1318          * 2) The TD is NOT active and it's the last TD in the chain
1319          *
1320          * and a third way the first uncompleted TD is found:
1321          *
1322          * 3) The TD is active and the previous TD is NOT active
1323          *
1324          * Control and Isochronous ignore the toggle, so this is safe
1325          * for all types
1326          *
1327          * FIXME: The toggle fixups won't be 100% reliable until we
1328          * change over to using a single queue for each endpoint and
1329          * stop the queue before unlinking.
1330          */
1331         head = &urbp->td_list;
1332         list_for_each_entry(td, head, list) {
1333                 unsigned int ctrlstat = td_status(td);
1334
1335                 if (!(ctrlstat & TD_CTRL_ACTIVE) &&
1336                                 (uhci_actual_length(ctrlstat) <
1337                                  uhci_expected_length(td_token(td)) ||
1338                                 td->list.next == head))
1339                         usb_settoggle(urb->dev, uhci_endpoint(td_token(td)),
1340                                 uhci_packetout(td_token(td)),
1341                                 uhci_toggle(td_token(td)) ^ 1);
1342                 else if ((ctrlstat & TD_CTRL_ACTIVE) && !prevactive)
1343                         usb_settoggle(urb->dev, uhci_endpoint(td_token(td)),
1344                                 uhci_packetout(td_token(td)),
1345                                 uhci_toggle(td_token(td)));
1346
1347                 prevactive = ctrlstat & TD_CTRL_ACTIVE;
1348         }
1349
1350         uhci_delete_queued_urb(uhci, urb);
1351
1352         /* The interrupt loop will reclaim the QH's */
1353         uhci_remove_qh(uhci, urbp->qh);
1354         urbp->qh = NULL;
1355 }
1356
1357 static int uhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb)
1358 {
1359         struct uhci_hcd *uhci = hcd_to_uhci(hcd);
1360         unsigned long flags;
1361         struct urb_priv *urbp;
1362
1363         spin_lock_irqsave(&uhci->lock, flags);
1364         urbp = urb->hcpriv;
1365         if (!urbp)                      /* URB was never linked! */
1366                 goto done;
1367         list_del_init(&urbp->urb_list);
1368
1369         uhci_unlink_generic(uhci, urb);
1370
1371         uhci_get_current_frame_number(uhci);
1372         if (uhci->frame_number + uhci->is_stopped != uhci->urb_remove_age) {
1373                 uhci_remove_pending_urbps(uhci);
1374                 uhci->urb_remove_age = uhci->frame_number;
1375         }
1376
1377         /* If we're the first, set the next interrupt bit */
1378         if (list_empty(&uhci->urb_remove_list))
1379                 uhci_set_next_interrupt(uhci);
1380         list_add_tail(&urbp->urb_list, &uhci->urb_remove_list);
1381
1382 done:
1383         spin_unlock_irqrestore(&uhci->lock, flags);
1384         return 0;
1385 }
1386
1387 static int uhci_fsbr_timeout(struct uhci_hcd *uhci, struct urb *urb)
1388 {
1389         struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
1390         struct list_head *head;
1391         struct uhci_td *td;
1392         int count = 0;
1393
1394         uhci_dec_fsbr(uhci, urb);
1395
1396         urbp->fsbr_timeout = 1;
1397
1398         /*
1399          * Ideally we would want to fix qh->element as well, but it's
1400          * read/write by the HC, so that can introduce a race. It's not
1401          * really worth the hassle
1402          */
1403
1404         head = &urbp->td_list;
1405         list_for_each_entry(td, head, list) {
1406                 /*
1407                  * Make sure we don't do the last one (since it'll have the
1408                  * TERM bit set) as well as we skip every so many TD's to
1409                  * make sure it doesn't hog the bandwidth
1410                  */
1411                 if (td->list.next != head && (count % DEPTH_INTERVAL) ==
1412                                 (DEPTH_INTERVAL - 1))
1413                         td->link |= UHCI_PTR_DEPTH;
1414
1415                 count++;
1416         }
1417
1418         return 0;
1419 }
1420
1421 static void uhci_free_pending_qhs(struct uhci_hcd *uhci)
1422 {
1423         struct uhci_qh *qh, *tmp;
1424
1425         list_for_each_entry_safe(qh, tmp, &uhci->qh_remove_list, remove_list) {
1426                 list_del_init(&qh->remove_list);
1427
1428                 uhci_free_qh(uhci, qh);
1429         }
1430 }
1431
1432 static void uhci_free_pending_tds(struct uhci_hcd *uhci)
1433 {
1434         struct uhci_td *td, *tmp;
1435
1436         list_for_each_entry_safe(td, tmp, &uhci->td_remove_list, remove_list) {
1437                 list_del_init(&td->remove_list);
1438
1439                 uhci_free_td(uhci, td);
1440         }
1441 }
1442
1443 static void
1444 uhci_finish_urb(struct usb_hcd *hcd, struct urb *urb, struct pt_regs *regs)
1445 __releases(uhci->lock)
1446 __acquires(uhci->lock)
1447 {
1448         struct uhci_hcd *uhci = hcd_to_uhci(hcd);
1449
1450         uhci_destroy_urb_priv(uhci, urb);
1451
1452         spin_unlock(&uhci->lock);
1453         usb_hcd_giveback_urb(hcd, urb, regs);
1454         spin_lock(&uhci->lock);
1455 }
1456
1457 static void uhci_finish_completion(struct uhci_hcd *uhci, struct pt_regs *regs)
1458 {
1459         struct urb_priv *urbp, *tmp;
1460
1461         list_for_each_entry_safe(urbp, tmp, &uhci->complete_list, urb_list) {
1462                 struct urb *urb = urbp->urb;
1463
1464                 list_del_init(&urbp->urb_list);
1465                 uhci_finish_urb(uhci_to_hcd(uhci), urb, regs);
1466         }
1467 }
1468
1469 static void uhci_remove_pending_urbps(struct uhci_hcd *uhci)
1470 {
1471
1472         /* Splice the urb_remove_list onto the end of the complete_list */
1473         list_splice_init(&uhci->urb_remove_list, uhci->complete_list.prev);
1474 }
1475
1476 /* Process events in the schedule, but only in one thread at a time */
1477 static void uhci_scan_schedule(struct uhci_hcd *uhci, struct pt_regs *regs)
1478 {
1479         struct urb_priv *urbp, *tmp;
1480
1481         /* Don't allow re-entrant calls */
1482         if (uhci->scan_in_progress) {
1483                 uhci->need_rescan = 1;
1484                 return;
1485         }
1486         uhci->scan_in_progress = 1;
1487  rescan:
1488         uhci->need_rescan = 0;
1489
1490         uhci_clear_next_interrupt(uhci);
1491         uhci_get_current_frame_number(uhci);
1492
1493         if (uhci->frame_number + uhci->is_stopped != uhci->qh_remove_age)
1494                 uhci_free_pending_qhs(uhci);
1495         if (uhci->frame_number + uhci->is_stopped != uhci->td_remove_age)
1496                 uhci_free_pending_tds(uhci);
1497         if (uhci->frame_number + uhci->is_stopped != uhci->urb_remove_age)
1498                 uhci_remove_pending_urbps(uhci);
1499
1500         /* Walk the list of pending URBs to see which ones completed
1501          * (must be _safe because uhci_transfer_result() dequeues URBs) */
1502         list_for_each_entry_safe(urbp, tmp, &uhci->urb_list, urb_list) {
1503                 struct urb *urb = urbp->urb;
1504
1505                 /* Checks the status and does all of the magic necessary */
1506                 uhci_transfer_result(uhci, urb);
1507         }
1508         uhci_finish_completion(uhci, regs);
1509
1510         /* If the controller is stopped, we can finish these off right now */
1511         if (uhci->is_stopped) {
1512                 uhci_free_pending_qhs(uhci);
1513                 uhci_free_pending_tds(uhci);
1514                 uhci_remove_pending_urbps(uhci);
1515         }
1516
1517         if (uhci->need_rescan)
1518                 goto rescan;
1519         uhci->scan_in_progress = 0;
1520
1521         if (list_empty(&uhci->urb_remove_list) &&
1522             list_empty(&uhci->td_remove_list) &&
1523             list_empty(&uhci->qh_remove_list))
1524                 uhci_clear_next_interrupt(uhci);
1525         else
1526                 uhci_set_next_interrupt(uhci);
1527
1528         /* Wake up anyone waiting for an URB to complete */
1529         wake_up_all(&uhci->waitqh);
1530 }
1531
1532 static void check_fsbr(struct uhci_hcd *uhci)
1533 {
1534         struct urb_priv *up;
1535
1536         list_for_each_entry(up, &uhci->urb_list, urb_list) {
1537                 struct urb *u = up->urb;
1538
1539                 spin_lock(&u->lock);
1540
1541                 /* Check if the FSBR timed out */
1542                 if (up->fsbr && !up->fsbr_timeout && time_after_eq(jiffies, up->fsbrtime + IDLE_TIMEOUT))
1543                         uhci_fsbr_timeout(uhci, u);
1544
1545                 spin_unlock(&u->lock);
1546         }
1547
1548         /* Really disable FSBR */
1549         if (!uhci->fsbr && uhci->fsbrtimeout && time_after_eq(jiffies, uhci->fsbrtimeout)) {
1550                 uhci->fsbrtimeout = 0;
1551                 uhci->skel_term_qh->link = UHCI_PTR_TERM;
1552         }
1553 }