USB: wusb: add wusb_phy_rate sysfs file to host controllers
[linux-2.6.git] / 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/uwb/umc.h>
21 #include <linux/usb.h>
22
23 #include "../../wusbcore/wusbhc.h"
24
25 #include "whcd.h"
26
27 struct whc_qset *qset_alloc(struct whc *whc, gfp_t mem_flags)
28 {
29         struct whc_qset *qset;
30         dma_addr_t dma;
31
32         qset = dma_pool_alloc(whc->qset_pool, mem_flags, &dma);
33         if (qset == NULL)
34                 return NULL;
35         memset(qset, 0, sizeof(struct whc_qset));
36
37         qset->qset_dma = dma;
38         qset->whc = whc;
39
40         INIT_LIST_HEAD(&qset->list_node);
41         INIT_LIST_HEAD(&qset->stds);
42
43         return qset;
44 }
45
46 /**
47  * qset_fill_qh - fill the static endpoint state in a qset's QHead
48  * @qset: the qset whose QH needs initializing with static endpoint
49  *        state
50  * @urb:  an urb for a transfer to this endpoint
51  */
52 static void qset_fill_qh(struct whc *whc, struct whc_qset *qset, struct urb *urb)
53 {
54         struct usb_device *usb_dev = urb->dev;
55         struct wusb_dev *wusb_dev = usb_dev->wusb_dev;
56         struct usb_wireless_ep_comp_descriptor *epcd;
57         bool is_out;
58         uint8_t phy_rate;
59
60         is_out = usb_pipeout(urb->pipe);
61
62         qset->max_packet = le16_to_cpu(urb->ep->desc.wMaxPacketSize);
63
64         epcd = (struct usb_wireless_ep_comp_descriptor *)qset->ep->extra;
65         if (epcd) {
66                 qset->max_seq = epcd->bMaxSequence;
67                 qset->max_burst = epcd->bMaxBurst;
68         } else {
69                 qset->max_seq = 2;
70                 qset->max_burst = 1;
71         }
72
73         /*
74          * Initial PHY rate is 53.3 Mbit/s for control endpoints or
75          * the maximum supported by the device for other endpoints
76          * (unless limited by the user).
77          */
78         if (usb_pipecontrol(urb->pipe))
79                 phy_rate = UWB_PHY_RATE_53;
80         else {
81                 uint16_t phy_rates;
82
83                 phy_rates = le16_to_cpu(wusb_dev->wusb_cap_descr->wPHYRates);
84                 phy_rate = fls(phy_rates) - 1;
85                 if (phy_rate > whc->wusbhc.phy_rate)
86                         phy_rate = whc->wusbhc.phy_rate;
87         }
88
89         qset->qh.info1 = cpu_to_le32(
90                 QH_INFO1_EP(usb_pipeendpoint(urb->pipe))
91                 | (is_out ? QH_INFO1_DIR_OUT : QH_INFO1_DIR_IN)
92                 | usb_pipe_to_qh_type(urb->pipe)
93                 | QH_INFO1_DEV_INFO_IDX(wusb_port_no_to_idx(usb_dev->portnum))
94                 | QH_INFO1_MAX_PKT_LEN(qset->max_packet)
95                 );
96         qset->qh.info2 = cpu_to_le32(
97                 QH_INFO2_BURST(qset->max_burst)
98                 | QH_INFO2_DBP(0)
99                 | QH_INFO2_MAX_COUNT(3)
100                 | QH_INFO2_MAX_RETRY(3)
101                 | QH_INFO2_MAX_SEQ(qset->max_seq - 1)
102                 );
103         /* FIXME: where can we obtain these Tx parameters from?  Why
104          * doesn't the chip know what Tx power to use? It knows the Rx
105          * strength and can presumably guess the Tx power required
106          * from that? */
107         qset->qh.info3 = cpu_to_le32(
108                 QH_INFO3_TX_RATE(phy_rate)
109                 | QH_INFO3_TX_PWR(0) /* 0 == max power */
110                 );
111
112         qset->qh.cur_window = cpu_to_le32((1 << qset->max_burst) - 1);
113 }
114
115 /**
116  * qset_clear - clear fields in a qset so it may be reinserted into a
117  * schedule.
118  *
119  * The sequence number and current window are not cleared (see
120  * qset_reset()).
121  */
122 void qset_clear(struct whc *whc, struct whc_qset *qset)
123 {
124         qset->td_start = qset->td_end = qset->ntds = 0;
125
126         qset->qh.link = cpu_to_le32(QH_LINK_NTDS(8) | QH_LINK_T);
127         qset->qh.status = qset->qh.status & QH_STATUS_SEQ_MASK;
128         qset->qh.err_count = 0;
129         qset->qh.scratch[0] = 0;
130         qset->qh.scratch[1] = 0;
131         qset->qh.scratch[2] = 0;
132
133         memset(&qset->qh.overlay, 0, sizeof(qset->qh.overlay));
134
135         init_completion(&qset->remove_complete);
136 }
137
138 /**
139  * qset_reset - reset endpoint state in a qset.
140  *
141  * Clears the sequence number and current window.  This qset must not
142  * be in the ASL or PZL.
143  */
144 void qset_reset(struct whc *whc, struct whc_qset *qset)
145 {
146         qset->reset = 0;
147
148         qset->qh.status &= ~QH_STATUS_SEQ_MASK;
149         qset->qh.cur_window = cpu_to_le32((1 << qset->max_burst) - 1);
150 }
151
152 /**
153  * get_qset - get the qset for an async endpoint
154  *
155  * A new qset is created if one does not already exist.
156  */
157 struct whc_qset *get_qset(struct whc *whc, struct urb *urb,
158                                  gfp_t mem_flags)
159 {
160         struct whc_qset *qset;
161
162         qset = urb->ep->hcpriv;
163         if (qset == NULL) {
164                 qset = qset_alloc(whc, mem_flags);
165                 if (qset == NULL)
166                         return NULL;
167
168                 qset->ep = urb->ep;
169                 urb->ep->hcpriv = qset;
170                 qset_fill_qh(whc, qset, urb);
171         }
172         return qset;
173 }
174
175 void qset_remove_complete(struct whc *whc, struct whc_qset *qset)
176 {
177         qset->remove = 0;
178         list_del_init(&qset->list_node);
179         complete(&qset->remove_complete);
180 }
181
182 /**
183  * qset_add_qtds - add qTDs for an URB to a qset
184  *
185  * Returns true if the list (ASL/PZL) must be updated because (for a
186  * WHCI 0.95 controller) an activated qTD was pointed to be iCur.
187  */
188 enum whc_update qset_add_qtds(struct whc *whc, struct whc_qset *qset)
189 {
190         struct whc_std *std;
191         enum whc_update update = 0;
192
193         list_for_each_entry(std, &qset->stds, list_node) {
194                 struct whc_qtd *qtd;
195                 uint32_t status;
196
197                 if (qset->ntds >= WHCI_QSET_TD_MAX
198                     || (qset->pause_after_urb && std->urb != qset->pause_after_urb))
199                         break;
200
201                 if (std->qtd)
202                         continue; /* already has a qTD */
203
204                 qtd = std->qtd = &qset->qtd[qset->td_end];
205
206                 /* Fill in setup bytes for control transfers. */
207                 if (usb_pipecontrol(std->urb->pipe))
208                         memcpy(qtd->setup, std->urb->setup_packet, 8);
209
210                 status = QTD_STS_ACTIVE | QTD_STS_LEN(std->len);
211
212                 if (whc_std_last(std) && usb_pipeout(std->urb->pipe))
213                         status |= QTD_STS_LAST_PKT;
214
215                 /*
216                  * For an IN transfer the iAlt field should be set so
217                  * the h/w will automatically advance to the next
218                  * transfer. However, if there are 8 or more TDs
219                  * remaining in this transfer then iAlt cannot be set
220                  * as it could point to somewhere in this transfer.
221                  */
222                 if (std->ntds_remaining < WHCI_QSET_TD_MAX) {
223                         int ialt;
224                         ialt = (qset->td_end + std->ntds_remaining) % WHCI_QSET_TD_MAX;
225                         status |= QTD_STS_IALT(ialt);
226                 } else if (usb_pipein(std->urb->pipe))
227                         qset->pause_after_urb = std->urb;
228
229                 if (std->num_pointers)
230                         qtd->options = cpu_to_le32(QTD_OPT_IOC);
231                 else
232                         qtd->options = cpu_to_le32(QTD_OPT_IOC | QTD_OPT_SMALL);
233                 qtd->page_list_ptr = cpu_to_le64(std->dma_addr);
234
235                 qtd->status = cpu_to_le32(status);
236
237                 if (QH_STATUS_TO_ICUR(qset->qh.status) == qset->td_end)
238                         update = WHC_UPDATE_UPDATED;
239
240                 if (++qset->td_end >= WHCI_QSET_TD_MAX)
241                         qset->td_end = 0;
242                 qset->ntds++;
243         }
244
245         return update;
246 }
247
248 /**
249  * qset_remove_qtd - remove the first qTD from a qset.
250  *
251  * The qTD might be still active (if it's part of a IN URB that
252  * resulted in a short read) so ensure it's deactivated.
253  */
254 static void qset_remove_qtd(struct whc *whc, struct whc_qset *qset)
255 {
256         qset->qtd[qset->td_start].status = 0;
257
258         if (++qset->td_start >= WHCI_QSET_TD_MAX)
259                 qset->td_start = 0;
260         qset->ntds--;
261 }
262
263 static void qset_copy_bounce_to_sg(struct whc *whc, struct whc_std *std)
264 {
265         struct scatterlist *sg;
266         void *bounce;
267         size_t remaining, offset;
268
269         bounce = std->bounce_buf;
270         remaining = std->len;
271
272         sg = std->bounce_sg;
273         offset = std->bounce_offset;
274
275         while (remaining) {
276                 size_t len;
277
278                 len = min(sg->length - offset, remaining);
279                 memcpy(sg_virt(sg) + offset, bounce, len);
280
281                 bounce += len;
282                 remaining -= len;
283
284                 offset += len;
285                 if (offset >= sg->length) {
286                         sg = sg_next(sg);
287                         offset = 0;
288                 }
289         }
290
291 }
292
293 /**
294  * qset_free_std - remove an sTD and free it.
295  * @whc: the WHCI host controller
296  * @std: the sTD to remove and free.
297  */
298 void qset_free_std(struct whc *whc, struct whc_std *std)
299 {
300         list_del(&std->list_node);
301         if (std->bounce_buf) {
302                 bool is_out = usb_pipeout(std->urb->pipe);
303                 dma_addr_t dma_addr;
304
305                 if (std->num_pointers)
306                         dma_addr = le64_to_cpu(std->pl_virt[0].buf_ptr);
307                 else
308                         dma_addr = std->dma_addr;
309
310                 dma_unmap_single(whc->wusbhc.dev, dma_addr,
311                                  std->len, is_out ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
312                 if (!is_out)
313                         qset_copy_bounce_to_sg(whc, std);
314                 kfree(std->bounce_buf);
315         }
316         if (std->pl_virt) {
317                 if (std->dma_addr)
318                         dma_unmap_single(whc->wusbhc.dev, std->dma_addr,
319                                          std->num_pointers * sizeof(struct whc_page_list_entry),
320                                          DMA_TO_DEVICE);
321                 kfree(std->pl_virt);
322                 std->pl_virt = NULL;
323         }
324         kfree(std);
325 }
326
327 /**
328  * qset_remove_qtds - remove an URB's qTDs (and sTDs).
329  */
330 static void qset_remove_qtds(struct whc *whc, struct whc_qset *qset,
331                              struct urb *urb)
332 {
333         struct whc_std *std, *t;
334
335         list_for_each_entry_safe(std, t, &qset->stds, list_node) {
336                 if (std->urb != urb)
337                         break;
338                 if (std->qtd != NULL)
339                         qset_remove_qtd(whc, qset);
340                 qset_free_std(whc, std);
341         }
342 }
343
344 /**
345  * qset_free_stds - free any remaining sTDs for an URB.
346  */
347 static void qset_free_stds(struct whc_qset *qset, struct urb *urb)
348 {
349         struct whc_std *std, *t;
350
351         list_for_each_entry_safe(std, t, &qset->stds, list_node) {
352                 if (std->urb == urb)
353                         qset_free_std(qset->whc, std);
354         }
355 }
356
357 static int qset_fill_page_list(struct whc *whc, struct whc_std *std, gfp_t mem_flags)
358 {
359         dma_addr_t dma_addr = std->dma_addr;
360         dma_addr_t sp, ep;
361         size_t pl_len;
362         int p;
363
364         /* Short buffers don't need a page list. */
365         if (std->len <= WHCI_PAGE_SIZE) {
366                 std->num_pointers = 0;
367                 return 0;
368         }
369
370         sp = dma_addr & ~(WHCI_PAGE_SIZE-1);
371         ep = dma_addr + std->len;
372         std->num_pointers = DIV_ROUND_UP(ep - sp, WHCI_PAGE_SIZE);
373
374         pl_len = std->num_pointers * sizeof(struct whc_page_list_entry);
375         std->pl_virt = kmalloc(pl_len, mem_flags);
376         if (std->pl_virt == NULL)
377                 return -ENOMEM;
378         std->dma_addr = dma_map_single(whc->wusbhc.dev, std->pl_virt, pl_len, DMA_TO_DEVICE);
379
380         for (p = 0; p < std->num_pointers; p++) {
381                 std->pl_virt[p].buf_ptr = cpu_to_le64(dma_addr);
382                 dma_addr = (dma_addr + WHCI_PAGE_SIZE) & ~(WHCI_PAGE_SIZE-1);
383         }
384
385         return 0;
386 }
387
388 /**
389  * urb_dequeue_work - executes asl/pzl update and gives back the urb to the system.
390  */
391 static void urb_dequeue_work(struct work_struct *work)
392 {
393         struct whc_urb *wurb = container_of(work, struct whc_urb, dequeue_work);
394         struct whc_qset *qset = wurb->qset;
395         struct whc *whc = qset->whc;
396         unsigned long flags;
397
398         if (wurb->is_async == true)
399                 asl_update(whc, WUSBCMD_ASYNC_UPDATED
400                            | WUSBCMD_ASYNC_SYNCED_DB
401                            | WUSBCMD_ASYNC_QSET_RM);
402         else
403                 pzl_update(whc, WUSBCMD_PERIODIC_UPDATED
404                            | WUSBCMD_PERIODIC_SYNCED_DB
405                            | WUSBCMD_PERIODIC_QSET_RM);
406
407         spin_lock_irqsave(&whc->lock, flags);
408         qset_remove_urb(whc, qset, wurb->urb, wurb->status);
409         spin_unlock_irqrestore(&whc->lock, flags);
410 }
411
412 static struct whc_std *qset_new_std(struct whc *whc, struct whc_qset *qset,
413                                     struct urb *urb, gfp_t mem_flags)
414 {
415         struct whc_std *std;
416
417         std = kzalloc(sizeof(struct whc_std), mem_flags);
418         if (std == NULL)
419                 return NULL;
420
421         std->urb = urb;
422         std->qtd = NULL;
423
424         INIT_LIST_HEAD(&std->list_node);
425         list_add_tail(&std->list_node, &qset->stds);
426
427         return std;
428 }
429
430 static int qset_add_urb_sg(struct whc *whc, struct whc_qset *qset, struct urb *urb,
431                            gfp_t mem_flags)
432 {
433         size_t remaining;
434         struct scatterlist *sg;
435         int i;
436         int ntds = 0;
437         struct whc_std *std = NULL;
438         struct whc_page_list_entry *entry;
439         dma_addr_t prev_end = 0;
440         size_t pl_len;
441         int p = 0;
442
443         remaining = urb->transfer_buffer_length;
444
445         for_each_sg(urb->sg->sg, sg, urb->num_sgs, i) {
446                 dma_addr_t dma_addr;
447                 size_t dma_remaining;
448                 dma_addr_t sp, ep;
449                 int num_pointers;
450
451                 if (remaining == 0) {
452                         break;
453                 }
454
455                 dma_addr = sg_dma_address(sg);
456                 dma_remaining = min_t(size_t, sg_dma_len(sg), remaining);
457
458                 while (dma_remaining) {
459                         size_t dma_len;
460
461                         /*
462                          * We can use the previous std (if it exists) provided that:
463                          * - the previous one ended on a page boundary.
464                          * - the current one begins on a page boundary.
465                          * - the previous one isn't full.
466                          *
467                          * If a new std is needed but the previous one
468                          * did not end on a wMaxPacketSize boundary
469                          * then this sg list cannot be mapped onto
470                          * multiple qTDs.  Return an error and let the
471                          * caller sort it out.
472                          */
473                         if (!std
474                             || (prev_end & (WHCI_PAGE_SIZE-1))
475                             || (dma_addr & (WHCI_PAGE_SIZE-1))
476                             || std->len + WHCI_PAGE_SIZE > QTD_MAX_XFER_SIZE) {
477                                 if (prev_end % qset->max_packet != 0)
478                                         return -EINVAL;
479                                 std = qset_new_std(whc, qset, urb, mem_flags);
480                                 if (std == NULL) {
481                                         return -ENOMEM;
482                                 }
483                                 ntds++;
484                                 p = 0;
485                         }
486
487                         dma_len = dma_remaining;
488
489                         /*
490                          * If the remainder in this element doesn't
491                          * fit in a single qTD, end the qTD on a
492                          * wMaxPacketSize boundary.
493                          */
494                         if (std->len + dma_len > QTD_MAX_XFER_SIZE) {
495                                 dma_len = QTD_MAX_XFER_SIZE - std->len;
496                                 ep = ((dma_addr + dma_len) / qset->max_packet) * qset->max_packet;
497                                 dma_len = ep - dma_addr;
498                         }
499
500                         std->len += dma_len;
501                         std->ntds_remaining = -1; /* filled in later */
502
503                         sp = dma_addr & ~(WHCI_PAGE_SIZE-1);
504                         ep = dma_addr + dma_len;
505                         num_pointers = DIV_ROUND_UP(ep - sp, WHCI_PAGE_SIZE);
506                         std->num_pointers += num_pointers;
507
508                         pl_len = std->num_pointers * sizeof(struct whc_page_list_entry);
509
510                         std->pl_virt = krealloc(std->pl_virt, pl_len, mem_flags);
511                         if (std->pl_virt == NULL) {
512                                 return -ENOMEM;
513                         }
514
515                         for (;p < std->num_pointers; p++, entry++) {
516                                 std->pl_virt[p].buf_ptr = cpu_to_le64(dma_addr);
517                                 dma_addr = (dma_addr + WHCI_PAGE_SIZE) & ~(WHCI_PAGE_SIZE-1);
518                         }
519
520                         prev_end = dma_addr = ep;
521                         dma_remaining -= dma_len;
522                         remaining -= dma_len;
523                 }
524         }
525
526         /* Now the number of stds is know, go back and fill in
527            std->ntds_remaining. */
528         list_for_each_entry(std, &qset->stds, list_node) {
529                 if (std->ntds_remaining == -1) {
530                         pl_len = std->num_pointers * sizeof(struct whc_page_list_entry);
531                         std->ntds_remaining = ntds--;
532                         std->dma_addr = dma_map_single(whc->wusbhc.dev, std->pl_virt,
533                                                        pl_len, DMA_TO_DEVICE);
534                 }
535         }
536         return 0;
537 }
538
539 /**
540  * qset_add_urb_sg_linearize - add an urb with sg list, copying the data
541  *
542  * If the URB contains an sg list whose elements cannot be directly
543  * mapped to qTDs then the data must be transferred via bounce
544  * buffers.
545  */
546 static int qset_add_urb_sg_linearize(struct whc *whc, struct whc_qset *qset,
547                                      struct urb *urb, gfp_t mem_flags)
548 {
549         bool is_out = usb_pipeout(urb->pipe);
550         size_t max_std_len;
551         size_t remaining;
552         int ntds = 0;
553         struct whc_std *std = NULL;
554         void *bounce = NULL;
555         struct scatterlist *sg;
556         int i;
557
558         /* limit maximum bounce buffer to 16 * 3.5 KiB ~= 28 k */
559         max_std_len = qset->max_burst * qset->max_packet;
560
561         remaining = urb->transfer_buffer_length;
562
563         for_each_sg(urb->sg->sg, sg, urb->sg->nents, i) {
564                 size_t len;
565                 size_t sg_remaining;
566                 void *orig;
567
568                 if (remaining == 0) {
569                         break;
570                 }
571
572                 sg_remaining = min_t(size_t, remaining, sg->length);
573                 orig = sg_virt(sg);
574
575                 while (sg_remaining) {
576                         if (!std || std->len == max_std_len) {
577                                 std = qset_new_std(whc, qset, urb, mem_flags);
578                                 if (std == NULL)
579                                         return -ENOMEM;
580                                 std->bounce_buf = kmalloc(max_std_len, mem_flags);
581                                 if (std->bounce_buf == NULL)
582                                         return -ENOMEM;
583                                 std->bounce_sg = sg;
584                                 std->bounce_offset = orig - sg_virt(sg);
585                                 bounce = std->bounce_buf;
586                                 ntds++;
587                         }
588
589                         len = min(sg_remaining, max_std_len - std->len);
590
591                         if (is_out)
592                                 memcpy(bounce, orig, len);
593
594                         std->len += len;
595                         std->ntds_remaining = -1; /* filled in later */
596
597                         bounce += len;
598                         orig += len;
599                         sg_remaining -= len;
600                         remaining -= len;
601                 }
602         }
603
604         /*
605          * For each of the new sTDs, map the bounce buffers, create
606          * page lists (if necessary), and fill in std->ntds_remaining.
607          */
608         list_for_each_entry(std, &qset->stds, list_node) {
609                 if (std->ntds_remaining != -1)
610                         continue;
611
612                 std->dma_addr = dma_map_single(&whc->umc->dev, std->bounce_buf, std->len,
613                                                is_out ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
614
615                 if (qset_fill_page_list(whc, std, mem_flags) < 0)
616                         return -ENOMEM;
617
618                 std->ntds_remaining = ntds--;
619         }
620
621         return 0;
622 }
623
624 /**
625  * qset_add_urb - add an urb to the qset's queue.
626  *
627  * The URB is chopped into sTDs, one for each qTD that will required.
628  * At least one qTD (and sTD) is required even if the transfer has no
629  * data (e.g., for some control transfers).
630  */
631 int qset_add_urb(struct whc *whc, struct whc_qset *qset, struct urb *urb,
632         gfp_t mem_flags)
633 {
634         struct whc_urb *wurb;
635         int remaining = urb->transfer_buffer_length;
636         u64 transfer_dma = urb->transfer_dma;
637         int ntds_remaining;
638         int ret;
639
640         wurb = kzalloc(sizeof(struct whc_urb), mem_flags);
641         if (wurb == NULL)
642                 goto err_no_mem;
643         urb->hcpriv = wurb;
644         wurb->qset = qset;
645         wurb->urb = urb;
646         INIT_WORK(&wurb->dequeue_work, urb_dequeue_work);
647
648         if (urb->sg) {
649                 ret = qset_add_urb_sg(whc, qset, urb, mem_flags);
650                 if (ret == -EINVAL) {
651                         qset_free_stds(qset, urb);
652                         ret = qset_add_urb_sg_linearize(whc, qset, urb, mem_flags);
653                 }
654                 if (ret < 0)
655                         goto err_no_mem;
656                 return 0;
657         }
658
659         ntds_remaining = DIV_ROUND_UP(remaining, QTD_MAX_XFER_SIZE);
660         if (ntds_remaining == 0)
661                 ntds_remaining = 1;
662
663         while (ntds_remaining) {
664                 struct whc_std *std;
665                 size_t std_len;
666
667                 std_len = remaining;
668                 if (std_len > QTD_MAX_XFER_SIZE)
669                         std_len = QTD_MAX_XFER_SIZE;
670
671                 std = qset_new_std(whc, qset, urb, mem_flags);
672                 if (std == NULL)
673                         goto err_no_mem;
674
675                 std->dma_addr = transfer_dma;
676                 std->len = std_len;
677                 std->ntds_remaining = ntds_remaining;
678
679                 if (qset_fill_page_list(whc, std, mem_flags) < 0)
680                         goto err_no_mem;
681
682                 ntds_remaining--;
683                 remaining -= std_len;
684                 transfer_dma += std_len;
685         }
686
687         return 0;
688
689 err_no_mem:
690         qset_free_stds(qset, urb);
691         return -ENOMEM;
692 }
693
694 /**
695  * qset_remove_urb - remove an URB from the urb queue.
696  *
697  * The URB is returned to the USB subsystem.
698  */
699 void qset_remove_urb(struct whc *whc, struct whc_qset *qset,
700                             struct urb *urb, int status)
701 {
702         struct wusbhc *wusbhc = &whc->wusbhc;
703         struct whc_urb *wurb = urb->hcpriv;
704
705         usb_hcd_unlink_urb_from_ep(&wusbhc->usb_hcd, urb);
706         /* Drop the lock as urb->complete() may enqueue another urb. */
707         spin_unlock(&whc->lock);
708         wusbhc_giveback_urb(wusbhc, urb, status);
709         spin_lock(&whc->lock);
710
711         kfree(wurb);
712 }
713
714 /**
715  * get_urb_status_from_qtd - get the completed urb status from qTD status
716  * @urb:    completed urb
717  * @status: qTD status
718  */
719 static int get_urb_status_from_qtd(struct urb *urb, u32 status)
720 {
721         if (status & QTD_STS_HALTED) {
722                 if (status & QTD_STS_DBE)
723                         return usb_pipein(urb->pipe) ? -ENOSR : -ECOMM;
724                 else if (status & QTD_STS_BABBLE)
725                         return -EOVERFLOW;
726                 else if (status & QTD_STS_RCE)
727                         return -ETIME;
728                 return -EPIPE;
729         }
730         if (usb_pipein(urb->pipe)
731             && (urb->transfer_flags & URB_SHORT_NOT_OK)
732             && urb->actual_length < urb->transfer_buffer_length)
733                 return -EREMOTEIO;
734         return 0;
735 }
736
737 /**
738  * process_inactive_qtd - process an inactive (but not halted) qTD.
739  *
740  * Update the urb with the transfer bytes from the qTD, if the urb is
741  * completely transfered or (in the case of an IN only) the LPF is
742  * set, then the transfer is complete and the urb should be returned
743  * to the system.
744  */
745 void process_inactive_qtd(struct whc *whc, struct whc_qset *qset,
746                                  struct whc_qtd *qtd)
747 {
748         struct whc_std *std = list_first_entry(&qset->stds, struct whc_std, list_node);
749         struct urb *urb = std->urb;
750         uint32_t status;
751         bool complete;
752
753         status = le32_to_cpu(qtd->status);
754
755         urb->actual_length += std->len - QTD_STS_TO_LEN(status);
756
757         if (usb_pipein(urb->pipe) && (status & QTD_STS_LAST_PKT))
758                 complete = true;
759         else
760                 complete = whc_std_last(std);
761
762         qset_remove_qtd(whc, qset);
763         qset_free_std(whc, std);
764
765         /*
766          * Transfers for this URB are complete?  Then return it to the
767          * USB subsystem.
768          */
769         if (complete) {
770                 qset_remove_qtds(whc, qset, urb);
771                 qset_remove_urb(whc, qset, urb, get_urb_status_from_qtd(urb, status));
772
773                 /*
774                  * If iAlt isn't valid then the hardware didn't
775                  * advance iCur. Adjust the start and end pointers to
776                  * match iCur.
777                  */
778                 if (!(status & QTD_STS_IALT_VALID))
779                         qset->td_start = qset->td_end
780                                 = QH_STATUS_TO_ICUR(le16_to_cpu(qset->qh.status));
781                 qset->pause_after_urb = NULL;
782         }
783 }
784
785 /**
786  * process_halted_qtd - process a qset with a halted qtd
787  *
788  * Remove all the qTDs for the failed URB and return the failed URB to
789  * the USB subsystem.  Then remove all other qTDs so the qset can be
790  * removed.
791  *
792  * FIXME: this is the point where rate adaptation can be done.  If a
793  * transfer failed because it exceeded the maximum number of retries
794  * then it could be reactivated with a slower rate without having to
795  * remove the qset.
796  */
797 void process_halted_qtd(struct whc *whc, struct whc_qset *qset,
798                                struct whc_qtd *qtd)
799 {
800         struct whc_std *std = list_first_entry(&qset->stds, struct whc_std, list_node);
801         struct urb *urb = std->urb;
802         int urb_status;
803
804         urb_status = get_urb_status_from_qtd(urb, le32_to_cpu(qtd->status));
805
806         qset_remove_qtds(whc, qset, urb);
807         qset_remove_urb(whc, qset, urb, urb_status);
808
809         list_for_each_entry(std, &qset->stds, list_node) {
810                 if (qset->ntds == 0)
811                         break;
812                 qset_remove_qtd(whc, qset);
813                 std->qtd = NULL;
814         }
815
816         qset->remove = 1;
817 }
818
819 void qset_free(struct whc *whc, struct whc_qset *qset)
820 {
821         dma_pool_free(whc->qset_pool, qset, qset->qset_dma);
822 }
823
824 /**
825  * qset_delete - wait for a qset to be unused, then free it.
826  */
827 void qset_delete(struct whc *whc, struct whc_qset *qset)
828 {
829         wait_for_completion(&qset->remove_complete);
830         qset_free(whc, qset);
831 }