drivers/usb/host/whci/qset.c

   1 /*
   2  * Wireless Host Controller (WHC) qset management.
   3  *
   4  * Copyright (C) 2007 Cambridge Silicon Radio Ltd.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License version
   8  * 2 as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18 #include <linux/kernel.h>
  19 #include <linux/dma-mapping.h>
  20 #include <linux/slab.h>
  21 #include <linux/uwb/umc.h>
  22 #include <linux/usb.h>
  23
  24 #include "../../wusbcore/wusbhc.h"
  25
  26 #include "whcd.h"
  27
  28 struct whc_qset *qset_alloc(struct whc *whc, gfp_t mem_flags)
  29 {
  30         struct whc_qset *qset;
  31         dma_addr_t dma;
  32
  33         qset = dma_pool_alloc(whc->qset_pool, mem_flags, &dma);
  34         if (qset == NULL)
  35                 return NULL;
  36         memset(qset, 0, sizeof(struct whc_qset));
  37
  38         qset->qset_dma = dma;
  39         qset->whc = whc;
  40
  41         INIT_LIST_HEAD(&qset->list_node);
  42         INIT_LIST_HEAD(&qset->stds);
  43
  44         return qset;
  45 }
  46
  47 /**
  48  * qset_fill_qh - fill the static endpoint state in a qset's QHead
  49  * @qset: the qset whose QH needs initializing with static endpoint
  50  *        state
  51  * @urb:  an urb for a transfer to this endpoint
  52  */
  53 static void qset_fill_qh(struct whc *whc, struct whc_qset *qset, struct urb *urb)
  54 {
  55         struct usb_device *usb_dev = urb->dev;
  56         struct wusb_dev *wusb_dev = usb_dev->wusb_dev;
  57         struct usb_wireless_ep_comp_descriptor *epcd;
  58         bool is_out;
  59         uint8_t phy_rate;
  60
  61         is_out = usb_pipeout(urb->pipe);
  62
  63         qset->max_packet = le16_to_cpu(urb->ep->desc.wMaxPacketSize);
  64
  65         epcd = (struct usb_wireless_ep_comp_descriptor *)qset->ep->extra;
  66         if (epcd) {
  67                 qset->max_seq = epcd->bMaxSequence;
  68                 qset->max_burst = epcd->bMaxBurst;
  69         } else {
  70                 qset->max_seq = 2;
  71                 qset->max_burst = 1;
  72         }
  73
  74         /*
  75          * Initial PHY rate is 53.3 Mbit/s for control endpoints or
  76          * the maximum supported by the device for other endpoints
  77          * (unless limited by the user).
  78          */
  79         if (usb_pipecontrol(urb->pipe))
  80                 phy_rate = UWB_PHY_RATE_53;
  81         else {
  82                 uint16_t phy_rates;
  83
  84                 phy_rates = le16_to_cpu(wusb_dev->wusb_cap_descr->wPHYRates);
  85                 phy_rate = fls(phy_rates) - 1;
  86                 if (phy_rate > whc->wusbhc.phy_rate)
  87                         phy_rate = whc->wusbhc.phy_rate;
  88         }
  89
  90         qset->qh.info1 = cpu_to_le32(
  91                 QH_INFO1_EP(usb_pipeendpoint(urb->pipe))
  92                 | (is_out ? QH_INFO1_DIR_OUT : QH_INFO1_DIR_IN)
  93                 | usb_pipe_to_qh_type(urb->pipe)
  94                 | QH_INFO1_DEV_INFO_IDX(wusb_port_no_to_idx(usb_dev->portnum))
  95                 | QH_INFO1_MAX_PKT_LEN(qset->max_packet)
  96                 );
  97         qset->qh.info2 = cpu_to_le32(
  98                 QH_INFO2_BURST(qset->max_burst)
  99                 | QH_INFO2_DBP(0)
 100                 | QH_INFO2_MAX_COUNT(3)
 101                 | QH_INFO2_MAX_RETRY(3)
 102                 | QH_INFO2_MAX_SEQ(qset->max_seq - 1)
 103                 );
 104         /* FIXME: where can we obtain these Tx parameters from?  Why
 105          * doesn't the chip know what Tx power to use? It knows the Rx
 106          * strength and can presumably guess the Tx power required
 107          * from that? */
 108         qset->qh.info3 = cpu_to_le32(
 109                 QH_INFO3_TX_RATE(phy_rate)
 110                 | QH_INFO3_TX_PWR(0) /* 0 == max power */
 111                 );
 112
 113         qset->qh.cur_window = cpu_to_le32((1 << qset->max_burst) - 1);
 114 }
 115
 116 /**
 117  * qset_clear - clear fields in a qset so it may be reinserted into a
 118  * schedule.
 119  *
 120  * The sequence number and current window are not cleared (see
 121  * qset_reset()).
 122  */
 123 void qset_clear(struct whc *whc, struct whc_qset *qset)
 124 {
 125         qset->td_start = qset->td_end = qset->ntds = 0;
 126
 127         qset->qh.link = cpu_to_le32(QH_LINK_NTDS(8) | QH_LINK_T);
 128         qset->qh.status = qset->qh.status & QH_STATUS_SEQ_MASK;
 129         qset->qh.err_count = 0;
 130         qset->qh.scratch[0] = 0;
 131         qset->qh.scratch[1] = 0;
 132         qset->qh.scratch[2] = 0;
 133
 134         memset(&qset->qh.overlay, 0, sizeof(qset->qh.overlay));
 135
 136         init_completion(&qset->remove_complete);
 137 }
 138
 139 /**
 140  * qset_reset - reset endpoint state in a qset.
 141  *
 142  * Clears the sequence number and current window.  This qset must not
 143  * be in the ASL or PZL.
 144  */
 145 void qset_reset(struct whc *whc, struct whc_qset *qset)
 146 {
 147         qset->reset = 0;
 148
 149         qset->qh.status &= ~QH_STATUS_SEQ_MASK;
 150         qset->qh.cur_window = cpu_to_le32((1 << qset->max_burst) - 1);
 151 }
 152
 153 /**
 154  * get_qset - get the qset for an async endpoint
 155  *
 156  * A new qset is created if one does not already exist.
 157  */
 158 struct whc_qset *get_qset(struct whc *whc, struct urb *urb,
 159                                  gfp_t mem_flags)
 160 {
 161         struct whc_qset *qset;
 162
 163         qset = urb->ep->hcpriv;
 164         if (qset == NULL) {
 165                 qset = qset_alloc(whc, mem_flags);
 166                 if (qset == NULL)
 167                         return NULL;
 168
 169                 qset->ep = urb->ep;
 170                 urb->ep->hcpriv = qset;
 171                 qset_fill_qh(whc, qset, urb);
 172         }
 173         return qset;
 174 }
 175
 176 void qset_remove_complete(struct whc *whc, struct whc_qset *qset)
 177 {
 178         qset->remove = 0;
 179         list_del_init(&qset->list_node);
 180         complete(&qset->remove_complete);
 181 }
 182
 183 /**
 184  * qset_add_qtds - add qTDs for an URB to a qset
 185  *
 186  * Returns true if the list (ASL/PZL) must be updated because (for a
 187  * WHCI 0.95 controller) an activated qTD was pointed to be iCur.
 188  */
 189 enum whc_update qset_add_qtds(struct whc *whc, struct whc_qset *qset)
 190 {
 191         struct whc_std *std;
 192         enum whc_update update = 0;
 193
 194         list_for_each_entry(std, &qset->stds, list_node) {
 195                 struct whc_qtd *qtd;
 196                 uint32_t status;
 197
 198                 if (qset->ntds >= WHCI_QSET_TD_MAX
 199                     || (qset->pause_after_urb && std->urb != qset->pause_after_urb))
 200                         break;
 201
 202                 if (std->qtd)
 203                         continue; /* already has a qTD */
 204
 205                 qtd = std->qtd = &qset->qtd[qset->td_end];
 206
 207                 /* Fill in setup bytes for control transfers. */
 208                 if (usb_pipecontrol(std->urb->pipe))
 209                         memcpy(qtd->setup, std->urb->setup_packet, 8);
 210
 211                 status = QTD_STS_ACTIVE | QTD_STS_LEN(std->len);
 212
 213                 if (whc_std_last(std) && usb_pipeout(std->urb->pipe))
 214                         status |= QTD_STS_LAST_PKT;
 215
 216                 /*
 217                  * For an IN transfer the iAlt field should be set so
 218                  * the h/w will automatically advance to the next
 219                  * transfer. However, if there are 8 or more TDs
 220                  * remaining in this transfer then iAlt cannot be set
 221                  * as it could point to somewhere in this transfer.
 222                  */
 223                 if (std->ntds_remaining < WHCI_QSET_TD_MAX) {
 224                         int ialt;
 225                         ialt = (qset->td_end + std->ntds_remaining) % WHCI_QSET_TD_MAX;
 226                         status |= QTD_STS_IALT(ialt);
 227                 } else if (usb_pipein(std->urb->pipe))
 228                         qset->pause_after_urb = std->urb;
 229
 230                 if (std->num_pointers)
 231                         qtd->options = cpu_to_le32(QTD_OPT_IOC);
 232                 else
 233                         qtd->options = cpu_to_le32(QTD_OPT_IOC | QTD_OPT_SMALL);
 234                 qtd->page_list_ptr = cpu_to_le64(std->dma_addr);
 235
 236                 qtd->status = cpu_to_le32(status);
 237
 238                 if (QH_STATUS_TO_ICUR(qset->qh.status) == qset->td_end)
 239                         update = WHC_UPDATE_UPDATED;
 240
 241                 if (++qset->td_end >= WHCI_QSET_TD_MAX)
 242                         qset->td_end = 0;
 243                 qset->ntds++;
 244         }
 245
 246         return update;
 247 }
 248
 249 /**
 250  * qset_remove_qtd - remove the first qTD from a qset.
 251  *
 252  * The qTD might be still active (if it's part of a IN URB that
 253  * resulted in a short read) so ensure it's deactivated.
 254  */
 255 static void qset_remove_qtd(struct whc *whc, struct whc_qset *qset)
 256 {
 257         qset->qtd[qset->td_start].status = 0;
 258
 259         if (++qset->td_start >= WHCI_QSET_TD_MAX)
 260                 qset->td_start = 0;
 261         qset->ntds--;
 262 }
 263
 264 static void qset_copy_bounce_to_sg(struct whc *whc, struct whc_std *std)
 265 {
 266         struct scatterlist *sg;
 267         void *bounce;
 268         size_t remaining, offset;
 269
 270         bounce = std->bounce_buf;
 271         remaining = std->len;
 272
 273         sg = std->bounce_sg;
 274         offset = std->bounce_offset;
 275
 276         while (remaining) {
 277                 size_t len;
 278
 279                 len = min(sg->length - offset, remaining);
 280                 memcpy(sg_virt(sg) + offset, bounce, len);
 281
 282                 bounce += len;
 283                 remaining -= len;
 284
 285                 offset += len;
 286                 if (offset >= sg->length) {
 287                         sg = sg_next(sg);
 288                         offset = 0;
 289                 }
 290         }
 291
 292 }
 293
 294 /**
 295  * qset_free_std - remove an sTD and free it.
 296  * @whc: the WHCI host controller
 297  * @std: the sTD to remove and free.
 298  */
 299 void qset_free_std(struct whc *whc, struct whc_std *std)
 300 {
 301         list_del(&std->list_node);
 302         if (std->bounce_buf) {
 303                 bool is_out = usb_pipeout(std->urb->pipe);
 304                 dma_addr_t dma_addr;
 305
 306                 if (std->num_pointers)
 307                         dma_addr = le64_to_cpu(std->pl_virt[0].buf_ptr);
 308                 else
 309                         dma_addr = std->dma_addr;
 310
 311                 dma_unmap_single(whc->wusbhc.dev, dma_addr,
 312                                  std->len, is_out ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
 313                 if (!is_out)
 314                         qset_copy_bounce_to_sg(whc, std);
 315                 kfree(std->bounce_buf);
 316         }
 317         if (std->pl_virt) {
 318                 if (std->dma_addr)
 319                         dma_unmap_single(whc->wusbhc.dev, std->dma_addr,
 320                                          std->num_pointers * sizeof(struct whc_page_list_entry),
 321                                          DMA_TO_DEVICE);
 322                 kfree(std->pl_virt);
 323                 std->pl_virt = NULL;
 324         }
 325         kfree(std);
 326 }
 327
 328 /**
 329  * qset_remove_qtds - remove an URB's qTDs (and sTDs).
 330  */
 331 static void qset_remove_qtds(struct whc *whc, struct whc_qset *qset,
 332                              struct urb *urb)
 333 {
 334         struct whc_std *std, *t;
 335
 336         list_for_each_entry_safe(std, t, &qset->stds, list_node) {
 337                 if (std->urb != urb)
 338                         break;
 339                 if (std->qtd != NULL)
 340                         qset_remove_qtd(whc, qset);
 341                 qset_free_std(whc, std);
 342         }
 343 }
 344
 345 /**
 346  * qset_free_stds - free any remaining sTDs for an URB.
 347  */
 348 static void qset_free_stds(struct whc_qset *qset, struct urb *urb)
 349 {
 350         struct whc_std *std, *t;
 351
 352         list_for_each_entry_safe(std, t, &qset->stds, list_node) {
 353                 if (std->urb == urb)
 354                         qset_free_std(qset->whc, std);
 355         }
 356 }
 357
 358 static int qset_fill_page_list(struct whc *whc, struct whc_std *std, gfp_t mem_flags)
 359 {
 360         dma_addr_t dma_addr = std->dma_addr;
 361         dma_addr_t sp, ep;
 362         size_t pl_len;
 363         int p;
 364
 365         /* Short buffers don't need a page list. */
 366         if (std->len <= WHCI_PAGE_SIZE) {
 367                 std->num_pointers = 0;
 368                 return 0;
 369         }
 370
 371         sp = dma_addr & ~(WHCI_PAGE_SIZE-1);
 372         ep = dma_addr + std->len;
 373         std->num_pointers = DIV_ROUND_UP(ep - sp, WHCI_PAGE_SIZE);
 374
 375         pl_len = std->num_pointers * sizeof(struct whc_page_list_entry);
 376         std->pl_virt = kmalloc(pl_len, mem_flags);
 377         if (std->pl_virt == NULL)
 378                 return -ENOMEM;
 379         std->dma_addr = dma_map_single(whc->wusbhc.dev, std->pl_virt, pl_len, DMA_TO_DEVICE);
 380
 381         for (p = 0; p < std->num_pointers; p++) {
 382                 std->pl_virt[p].buf_ptr = cpu_to_le64(dma_addr);
 383                 dma_addr = (dma_addr + WHCI_PAGE_SIZE) & ~(WHCI_PAGE_SIZE-1);
 384         }
 385
 386         return 0;
 387 }
 388
 389 /**
 390  * urb_dequeue_work - executes asl/pzl update and gives back the urb to the system.
 391  */
 392 static void urb_dequeue_work(struct work_struct *work)
 393 {
 394         struct whc_urb *wurb = container_of(work, struct whc_urb, dequeue_work);
 395         struct whc_qset *qset = wurb->qset;
 396         struct whc *whc = qset->whc;
 397         unsigned long flags;
 398
 399         if (wurb->is_async == true)
 400                 asl_update(whc, WUSBCMD_ASYNC_UPDATED
 401                            | WUSBCMD_ASYNC_SYNCED_DB
 402                            | WUSBCMD_ASYNC_QSET_RM);
 403         else
 404                 pzl_update(whc, WUSBCMD_PERIODIC_UPDATED
 405                            | WUSBCMD_PERIODIC_SYNCED_DB
 406                            | WUSBCMD_PERIODIC_QSET_RM);
 407
 408         spin_lock_irqsave(&whc->lock, flags);
 409         qset_remove_urb(whc, qset, wurb->urb, wurb->status);
 410         spin_unlock_irqrestore(&whc->lock, flags);
 411 }
 412
 413 static struct whc_std *qset_new_std(struct whc *whc, struct whc_qset *qset,
 414                                     struct urb *urb, gfp_t mem_flags)
 415 {
 416         struct whc_std *std;
 417
 418         std = kzalloc(sizeof(struct whc_std), mem_flags);
 419         if (std == NULL)
 420                 return NULL;
 421
 422         std->urb = urb;
 423         std->qtd = NULL;
 424
 425         INIT_LIST_HEAD(&std->list_node);
 426         list_add_tail(&std->list_node, &qset->stds);
 427
 428         return std;
 429 }
 430
 431 static int qset_add_urb_sg(struct whc *whc, struct whc_qset *qset, struct urb *urb,
 432                            gfp_t mem_flags)
 433 {
 434         size_t remaining;
 435         struct scatterlist *sg;
 436         int i;
 437         int ntds = 0;
 438         struct whc_std *std = NULL;
 439         struct whc_page_list_entry *entry;
 440         dma_addr_t prev_end = 0;
 441         size_t pl_len;
 442         int p = 0;
 443
 444         remaining = urb->transfer_buffer_length;
 445
 446         for_each_sg(urb->sg, sg, urb->num_sgs, i) {
 447                 dma_addr_t dma_addr;
 448                 size_t dma_remaining;
 449                 dma_addr_t sp, ep;
 450                 int num_pointers;
 451
 452                 if (remaining == 0) {
 453                         break;
 454                 }
 455
 456                 dma_addr = sg_dma_address(sg);
 457                 dma_remaining = min_t(size_t, sg_dma_len(sg), remaining);
 458
 459                 while (dma_remaining) {
 460                         size_t dma_len;
 461
 462                         /*
 463                          * We can use the previous std (if it exists) provided that:
 464                          * - the previous one ended on a page boundary.
 465                          * - the current one begins on a page boundary.
 466                          * - the previous one isn't full.
 467                          *
 468                          * If a new std is needed but the previous one
 469                          * was not a whole number of packets then this
 470                          * sg list cannot be mapped onto multiple
 471                          * qTDs.  Return an error and let the caller
 472                          * sort it out.
 473                          */
 474                         if (!std
 475                             || (prev_end & (WHCI_PAGE_SIZE-1))
 476                             || (dma_addr & (WHCI_PAGE_SIZE-1))
 477                             || std->len + WHCI_PAGE_SIZE > QTD_MAX_XFER_SIZE) {
 478                                 if (std && std->len % qset->max_packet != 0)
 479                                         return -EINVAL;
 480                                 std = qset_new_std(whc, qset, urb, mem_flags);
 481                                 if (std == NULL) {
 482                                         return -ENOMEM;
 483                                 }
 484                                 ntds++;
 485                                 p = 0;
 486                         }
 487
 488                         dma_len = dma_remaining;
 489
 490                         /*
 491                          * If the remainder of this element doesn't
 492                          * fit in a single qTD, limit the qTD to a
 493                          * whole number of packets.  This allows the
 494                          * remainder to go into the next qTD.
 495                          */
 496                         if (std->len + dma_len > QTD_MAX_XFER_SIZE) {
 497                                 dma_len = (QTD_MAX_XFER_SIZE / qset->max_packet)
 498                                         * qset->max_packet - std->len;
 499                         }
 500
 501                         std->len += dma_len;
 502                         std->ntds_remaining = -1; /* filled in later */
 503
 504                         sp = dma_addr & ~(WHCI_PAGE_SIZE-1);
 505                         ep = dma_addr + dma_len;
 506                         num_pointers = DIV_ROUND_UP(ep - sp, WHCI_PAGE_SIZE);
 507                         std->num_pointers += num_pointers;
 508
 509                         pl_len = std->num_pointers * sizeof(struct whc_page_list_entry);
 510
 511                         std->pl_virt = krealloc(std->pl_virt, pl_len, mem_flags);
 512                         if (std->pl_virt == NULL) {
 513                                 return -ENOMEM;
 514                         }
 515
 516                         for (;p < std->num_pointers; p++, entry++) {
 517                                 std->pl_virt[p].buf_ptr = cpu_to_le64(dma_addr);
 518                                 dma_addr = (dma_addr + WHCI_PAGE_SIZE) & ~(WHCI_PAGE_SIZE-1);
 519                         }
 520
 521                         prev_end = dma_addr = ep;
 522                         dma_remaining -= dma_len;
 523                         remaining -= dma_len;
 524                 }
 525         }
 526
 527         /* Now the number of stds is know, go back and fill in
 528            std->ntds_remaining. */
 529         list_for_each_entry(std, &qset->stds, list_node) {
 530                 if (std->ntds_remaining == -1) {
 531                         pl_len = std->num_pointers * sizeof(struct whc_page_list_entry);
 532                         std->ntds_remaining = ntds--;
 533                         std->dma_addr = dma_map_single(whc->wusbhc.dev, std->pl_virt,
 534                                                        pl_len, DMA_TO_DEVICE);
 535                 }
 536         }
 537         return 0;
 538 }
 539
 540 /**
 541  * qset_add_urb_sg_linearize - add an urb with sg list, copying the data
 542  *
 543  * If the URB contains an sg list whose elements cannot be directly
 544  * mapped to qTDs then the data must be transferred via bounce
 545  * buffers.
 546  */
 547 static int qset_add_urb_sg_linearize(struct whc *whc, struct whc_qset *qset,
 548                                      struct urb *urb, gfp_t mem_flags)
 549 {
 550         bool is_out = usb_pipeout(urb->pipe);
 551         size_t max_std_len;
 552         size_t remaining;
 553         int ntds = 0;
 554         struct whc_std *std = NULL;
 555         void *bounce = NULL;
 556         struct scatterlist *sg;
 557         int i;
 558
 559         /* limit maximum bounce buffer to 16 * 3.5 KiB ~= 28 k */
 560         max_std_len = qset->max_burst * qset->max_packet;
 561
 562         remaining = urb->transfer_buffer_length;
 563
 564         for_each_sg(urb->sg, sg, urb->num_sgs, i) {
 565                 size_t len;
 566                 size_t sg_remaining;
 567                 void *orig;
 568
 569                 if (remaining == 0) {
 570                         break;
 571                 }
 572
 573                 sg_remaining = min_t(size_t, remaining, sg->length);
 574                 orig = sg_virt(sg);
 575
 576                 while (sg_remaining) {
 577                         if (!std || std->len == max_std_len) {
 578                                 std = qset_new_std(whc, qset, urb, mem_flags);
 579                                 if (std == NULL)
 580                                         return -ENOMEM;
 581                                 std->bounce_buf = kmalloc(max_std_len, mem_flags);
 582                                 if (std->bounce_buf == NULL)
 583                                         return -ENOMEM;
 584                                 std->bounce_sg = sg;
 585                                 std->bounce_offset = orig - sg_virt(sg);
 586                                 bounce = std->bounce_buf;
 587                                 ntds++;
 588                         }
 589
 590                         len = min(sg_remaining, max_std_len - std->len);
 591
 592                         if (is_out)
 593                                 memcpy(bounce, orig, len);
 594
 595                         std->len += len;
 596                         std->ntds_remaining = -1; /* filled in later */
 597
 598                         bounce += len;
 599                         orig += len;
 600                         sg_remaining -= len;
 601                         remaining -= len;
 602                 }
 603         }
 604
 605         /*
 606          * For each of the new sTDs, map the bounce buffers, create
 607          * page lists (if necessary), and fill in std->ntds_remaining.
 608          */
 609         list_for_each_entry(std, &qset->stds, list_node) {
 610                 if (std->ntds_remaining != -1)
 611                         continue;
 612
 613                 std->dma_addr = dma_map_single(&whc->umc->dev, std->bounce_buf, std->len,
 614                                                is_out ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
 615
 616                 if (qset_fill_page_list(whc, std, mem_flags) < 0)
 617                         return -ENOMEM;
 618
 619                 std->ntds_remaining = ntds--;
 620         }
 621
 622         return 0;
 623 }
 624
 625 /**
 626  * qset_add_urb - add an urb to the qset's queue.
 627  *
 628  * The URB is chopped into sTDs, one for each qTD that will required.
 629  * At least one qTD (and sTD) is required even if the transfer has no
 630  * data (e.g., for some control transfers).
 631  */
 632 int qset_add_urb(struct whc *whc, struct whc_qset *qset, struct urb *urb,
 633         gfp_t mem_flags)
 634 {
 635         struct whc_urb *wurb;
 636         int remaining = urb->transfer_buffer_length;
 637         u64 transfer_dma = urb->transfer_dma;
 638         int ntds_remaining;
 639         int ret;
 640
 641         wurb = kzalloc(sizeof(struct whc_urb), mem_flags);
 642         if (wurb == NULL)
 643                 goto err_no_mem;
 644         urb->hcpriv = wurb;
 645         wurb->qset = qset;
 646         wurb->urb = urb;
 647         INIT_WORK(&wurb->dequeue_work, urb_dequeue_work);
 648
 649         if (urb->num_sgs) {
 650                 ret = qset_add_urb_sg(whc, qset, urb, mem_flags);
 651                 if (ret == -EINVAL) {
 652                         qset_free_stds(qset, urb);
 653                         ret = qset_add_urb_sg_linearize(whc, qset, urb, mem_flags);
 654                 }
 655                 if (ret < 0)
 656                         goto err_no_mem;
 657                 return 0;
 658         }
 659
 660         ntds_remaining = DIV_ROUND_UP(remaining, QTD_MAX_XFER_SIZE);
 661         if (ntds_remaining == 0)
 662                 ntds_remaining = 1;
 663
 664         while (ntds_remaining) {
 665                 struct whc_std *std;
 666                 size_t std_len;
 667
 668                 std_len = remaining;
 669                 if (std_len > QTD_MAX_XFER_SIZE)
 670                         std_len = QTD_MAX_XFER_SIZE;
 671
 672                 std = qset_new_std(whc, qset, urb, mem_flags);
 673                 if (std == NULL)
 674                         goto err_no_mem;
 675
 676                 std->dma_addr = transfer_dma;
 677                 std->len = std_len;
 678                 std->ntds_remaining = ntds_remaining;
 679
 680                 if (qset_fill_page_list(whc, std, mem_flags) < 0)
 681                         goto err_no_mem;
 682
 683                 ntds_remaining--;
 684                 remaining -= std_len;
 685                 transfer_dma += std_len;
 686         }
 687
 688         return 0;
 689
 690 err_no_mem:
 691         qset_free_stds(qset, urb);
 692         return -ENOMEM;
 693 }
 694
 695 /**
 696  * qset_remove_urb - remove an URB from the urb queue.
 697  *
 698  * The URB is returned to the USB subsystem.
 699  */
 700 void qset_remove_urb(struct whc *whc, struct whc_qset *qset,
 701                             struct urb *urb, int status)
 702 {
 703         struct wusbhc *wusbhc = &whc->wusbhc;
 704         struct whc_urb *wurb = urb->hcpriv;
 705
 706         usb_hcd_unlink_urb_from_ep(&wusbhc->usb_hcd, urb);
 707         /* Drop the lock as urb->complete() may enqueue another urb. */
 708         spin_unlock(&whc->lock);
 709         wusbhc_giveback_urb(wusbhc, urb, status);
 710         spin_lock(&whc->lock);
 711
 712         kfree(wurb);
 713 }
 714
 715 /**
 716  * get_urb_status_from_qtd - get the completed urb status from qTD status
 717  * @urb:    completed urb
 718  * @status: qTD status
 719  */
 720 static int get_urb_status_from_qtd(struct urb *urb, u32 status)
 721 {
 722         if (status & QTD_STS_HALTED) {
 723                 if (status & QTD_STS_DBE)
 724                         return usb_pipein(urb->pipe) ? -ENOSR : -ECOMM;
 725                 else if (status & QTD_STS_BABBLE)
 726                         return -EOVERFLOW;
 727                 else if (status & QTD_STS_RCE)
 728                         return -ETIME;
 729                 return -EPIPE;
 730         }
 731         if (usb_pipein(urb->pipe)
 732             && (urb->transfer_flags & URB_SHORT_NOT_OK)
 733             && urb->actual_length < urb->transfer_buffer_length)
 734                 return -EREMOTEIO;
 735         return 0;
 736 }
 737
 738 /**
 739  * process_inactive_qtd - process an inactive (but not halted) qTD.
 740  *
 741  * Update the urb with the transfer bytes from the qTD, if the urb is
 742  * completely transfered or (in the case of an IN only) the LPF is
 743  * set, then the transfer is complete and the urb should be returned
 744  * to the system.
 745  */
 746 void process_inactive_qtd(struct whc *whc, struct whc_qset *qset,
 747                                  struct whc_qtd *qtd)
 748 {
 749         struct whc_std *std = list_first_entry(&qset->stds, struct whc_std, list_node);
 750         struct urb *urb = std->urb;
 751         uint32_t status;
 752         bool complete;
 753
 754         status = le32_to_cpu(qtd->status);
 755
 756         urb->actual_length += std->len - QTD_STS_TO_LEN(status);
 757
 758         if (usb_pipein(urb->pipe) && (status & QTD_STS_LAST_PKT))
 759                 complete = true;
 760         else
 761                 complete = whc_std_last(std);
 762
 763         qset_remove_qtd(whc, qset);
 764         qset_free_std(whc, std);
 765
 766         /*
 767          * Transfers for this URB are complete?  Then return it to the
 768          * USB subsystem.
 769          */
 770         if (complete) {
 771                 qset_remove_qtds(whc, qset, urb);
 772                 qset_remove_urb(whc, qset, urb, get_urb_status_from_qtd(urb, status));
 773
 774                 /*
 775                  * If iAlt isn't valid then the hardware didn't
 776                  * advance iCur. Adjust the start and end pointers to
 777                  * match iCur.
 778                  */
 779                 if (!(status & QTD_STS_IALT_VALID))
 780                         qset->td_start = qset->td_end
 781                                 = QH_STATUS_TO_ICUR(le16_to_cpu(qset->qh.status));
 782                 qset->pause_after_urb = NULL;
 783         }
 784 }
 785
 786 /**
 787  * process_halted_qtd - process a qset with a halted qtd
 788  *
 789  * Remove all the qTDs for the failed URB and return the failed URB to
 790  * the USB subsystem.  Then remove all other qTDs so the qset can be
 791  * removed.
 792  *
 793  * FIXME: this is the point where rate adaptation can be done.  If a
 794  * transfer failed because it exceeded the maximum number of retries
 795  * then it could be reactivated with a slower rate without having to
 796  * remove the qset.
 797  */
 798 void process_halted_qtd(struct whc *whc, struct whc_qset *qset,
 799                                struct whc_qtd *qtd)
 800 {
 801         struct whc_std *std = list_first_entry(&qset->stds, struct whc_std, list_node);
 802         struct urb *urb = std->urb;
 803         int urb_status;
 804
 805         urb_status = get_urb_status_from_qtd(urb, le32_to_cpu(qtd->status));
 806
 807         qset_remove_qtds(whc, qset, urb);
 808         qset_remove_urb(whc, qset, urb, urb_status);
 809
 810         list_for_each_entry(std, &qset->stds, list_node) {
 811                 if (qset->ntds == 0)
 812                         break;
 813                 qset_remove_qtd(whc, qset);
 814                 std->qtd = NULL;
 815         }
 816
 817         qset->remove = 1;
 818 }
 819
 820 void qset_free(struct whc *whc, struct whc_qset *qset)
 821 {
 822         dma_pool_free(whc->qset_pool, qset, qset->qset_dma);
 823 }
 824
 825 /**
 826  * qset_delete - wait for a qset to be unused, then free it.
 827  */
 828 void qset_delete(struct whc *whc, struct whc_qset *qset)
 829 {
 830         wait_for_completion(&qset->remove_complete);
 831         qset_free(whc, qset);
 832 }