Merge branch 'for-linus/samsung-2635' of git://git.fluff.org/bjdooks/linux
[cascardo/linux.git] / drivers / usb / host / xhci-ring.c
1 /*
2  * xHCI host controller driver
3  *
4  * Copyright (C) 2008 Intel Corp.
5  *
6  * Author: Sarah Sharp
7  * Some code borrowed from the Linux EHCI driver.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
16  * for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software Foundation,
20  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  */
22
23 /*
24  * Ring initialization rules:
25  * 1. Each segment is initialized to zero, except for link TRBs.
26  * 2. Ring cycle state = 0.  This represents Producer Cycle State (PCS) or
27  *    Consumer Cycle State (CCS), depending on ring function.
28  * 3. Enqueue pointer = dequeue pointer = address of first TRB in the segment.
29  *
30  * Ring behavior rules:
31  * 1. A ring is empty if enqueue == dequeue.  This means there will always be at
32  *    least one free TRB in the ring.  This is useful if you want to turn that
33  *    into a link TRB and expand the ring.
34  * 2. When incrementing an enqueue or dequeue pointer, if the next TRB is a
35  *    link TRB, then load the pointer with the address in the link TRB.  If the
36  *    link TRB had its toggle bit set, you may need to update the ring cycle
37  *    state (see cycle bit rules).  You may have to do this multiple times
38  *    until you reach a non-link TRB.
39  * 3. A ring is full if enqueue++ (for the definition of increment above)
40  *    equals the dequeue pointer.
41  *
42  * Cycle bit rules:
43  * 1. When a consumer increments a dequeue pointer and encounters a toggle bit
44  *    in a link TRB, it must toggle the ring cycle state.
45  * 2. When a producer increments an enqueue pointer and encounters a toggle bit
46  *    in a link TRB, it must toggle the ring cycle state.
47  *
48  * Producer rules:
49  * 1. Check if ring is full before you enqueue.
50  * 2. Write the ring cycle state to the cycle bit in the TRB you're enqueuing.
51  *    Update enqueue pointer between each write (which may update the ring
52  *    cycle state).
53  * 3. Notify consumer.  If SW is producer, it rings the doorbell for command
54  *    and endpoint rings.  If HC is the producer for the event ring,
55  *    and it generates an interrupt according to interrupt modulation rules.
56  *
57  * Consumer rules:
58  * 1. Check if TRB belongs to you.  If the cycle bit == your ring cycle state,
59  *    the TRB is owned by the consumer.
60  * 2. Update dequeue pointer (which may update the ring cycle state) and
61  *    continue processing TRBs until you reach a TRB which is not owned by you.
62  * 3. Notify the producer.  SW is the consumer for the event ring, and it
63  *   updates event ring dequeue pointer.  HC is the consumer for the command and
64  *   endpoint rings; it generates events on the event ring for these.
65  */
66
67 #include <linux/scatterlist.h>
68 #include <linux/slab.h>
69 #include "xhci.h"
70
71 /*
72  * Returns zero if the TRB isn't in this segment, otherwise it returns the DMA
73  * address of the TRB.
74  */
75 dma_addr_t xhci_trb_virt_to_dma(struct xhci_segment *seg,
76                 union xhci_trb *trb)
77 {
78         unsigned long segment_offset;
79
80         if (!seg || !trb || trb < seg->trbs)
81                 return 0;
82         /* offset in TRBs */
83         segment_offset = trb - seg->trbs;
84         if (segment_offset > TRBS_PER_SEGMENT)
85                 return 0;
86         return seg->dma + (segment_offset * sizeof(*trb));
87 }
88
89 /* Does this link TRB point to the first segment in a ring,
90  * or was the previous TRB the last TRB on the last segment in the ERST?
91  */
92 static inline bool last_trb_on_last_seg(struct xhci_hcd *xhci, struct xhci_ring *ring,
93                 struct xhci_segment *seg, union xhci_trb *trb)
94 {
95         if (ring == xhci->event_ring)
96                 return (trb == &seg->trbs[TRBS_PER_SEGMENT]) &&
97                         (seg->next == xhci->event_ring->first_seg);
98         else
99                 return trb->link.control & LINK_TOGGLE;
100 }
101
102 /* Is this TRB a link TRB or was the last TRB the last TRB in this event ring
103  * segment?  I.e. would the updated event TRB pointer step off the end of the
104  * event seg?
105  */
106 static inline int last_trb(struct xhci_hcd *xhci, struct xhci_ring *ring,
107                 struct xhci_segment *seg, union xhci_trb *trb)
108 {
109         if (ring == xhci->event_ring)
110                 return trb == &seg->trbs[TRBS_PER_SEGMENT];
111         else
112                 return (trb->link.control & TRB_TYPE_BITMASK) == TRB_TYPE(TRB_LINK);
113 }
114
115 static inline int enqueue_is_link_trb(struct xhci_ring *ring)
116 {
117         struct xhci_link_trb *link = &ring->enqueue->link;
118         return ((link->control & TRB_TYPE_BITMASK) == TRB_TYPE(TRB_LINK));
119 }
120
121 /* Updates trb to point to the next TRB in the ring, and updates seg if the next
122  * TRB is in a new segment.  This does not skip over link TRBs, and it does not
123  * effect the ring dequeue or enqueue pointers.
124  */
125 static void next_trb(struct xhci_hcd *xhci,
126                 struct xhci_ring *ring,
127                 struct xhci_segment **seg,
128                 union xhci_trb **trb)
129 {
130         if (last_trb(xhci, ring, *seg, *trb)) {
131                 *seg = (*seg)->next;
132                 *trb = ((*seg)->trbs);
133         } else {
134                 *trb = (*trb)++;
135         }
136 }
137
138 /*
139  * See Cycle bit rules. SW is the consumer for the event ring only.
140  * Don't make a ring full of link TRBs.  That would be dumb and this would loop.
141  */
142 static void inc_deq(struct xhci_hcd *xhci, struct xhci_ring *ring, bool consumer)
143 {
144         union xhci_trb *next = ++(ring->dequeue);
145         unsigned long long addr;
146
147         ring->deq_updates++;
148         /* Update the dequeue pointer further if that was a link TRB or we're at
149          * the end of an event ring segment (which doesn't have link TRBS)
150          */
151         while (last_trb(xhci, ring, ring->deq_seg, next)) {
152                 if (consumer && last_trb_on_last_seg(xhci, ring, ring->deq_seg, next)) {
153                         ring->cycle_state = (ring->cycle_state ? 0 : 1);
154                         if (!in_interrupt())
155                                 xhci_dbg(xhci, "Toggle cycle state for ring %p = %i\n",
156                                                 ring,
157                                                 (unsigned int) ring->cycle_state);
158                 }
159                 ring->deq_seg = ring->deq_seg->next;
160                 ring->dequeue = ring->deq_seg->trbs;
161                 next = ring->dequeue;
162         }
163         addr = (unsigned long long) xhci_trb_virt_to_dma(ring->deq_seg, ring->dequeue);
164         if (ring == xhci->event_ring)
165                 xhci_dbg(xhci, "Event ring deq = 0x%llx (DMA)\n", addr);
166         else if (ring == xhci->cmd_ring)
167                 xhci_dbg(xhci, "Command ring deq = 0x%llx (DMA)\n", addr);
168         else
169                 xhci_dbg(xhci, "Ring deq = 0x%llx (DMA)\n", addr);
170 }
171
172 /*
173  * See Cycle bit rules. SW is the consumer for the event ring only.
174  * Don't make a ring full of link TRBs.  That would be dumb and this would loop.
175  *
176  * If we've just enqueued a TRB that is in the middle of a TD (meaning the
177  * chain bit is set), then set the chain bit in all the following link TRBs.
178  * If we've enqueued the last TRB in a TD, make sure the following link TRBs
179  * have their chain bit cleared (so that each Link TRB is a separate TD).
180  *
181  * Section 6.4.4.1 of the 0.95 spec says link TRBs cannot have the chain bit
182  * set, but other sections talk about dealing with the chain bit set.  This was
183  * fixed in the 0.96 specification errata, but we have to assume that all 0.95
184  * xHCI hardware can't handle the chain bit being cleared on a link TRB.
185  *
186  * @more_trbs_coming:   Will you enqueue more TRBs before calling
187  *                      prepare_transfer()?
188  */
189 static void inc_enq(struct xhci_hcd *xhci, struct xhci_ring *ring,
190                 bool consumer, bool more_trbs_coming)
191 {
192         u32 chain;
193         union xhci_trb *next;
194         unsigned long long addr;
195
196         chain = ring->enqueue->generic.field[3] & TRB_CHAIN;
197         next = ++(ring->enqueue);
198
199         ring->enq_updates++;
200         /* Update the dequeue pointer further if that was a link TRB or we're at
201          * the end of an event ring segment (which doesn't have link TRBS)
202          */
203         while (last_trb(xhci, ring, ring->enq_seg, next)) {
204                 if (!consumer) {
205                         if (ring != xhci->event_ring) {
206                                 /*
207                                  * If the caller doesn't plan on enqueueing more
208                                  * TDs before ringing the doorbell, then we
209                                  * don't want to give the link TRB to the
210                                  * hardware just yet.  We'll give the link TRB
211                                  * back in prepare_ring() just before we enqueue
212                                  * the TD at the top of the ring.
213                                  */
214                                 if (!chain && !more_trbs_coming)
215                                         break;
216
217                                 /* If we're not dealing with 0.95 hardware,
218                                  * carry over the chain bit of the previous TRB
219                                  * (which may mean the chain bit is cleared).
220                                  */
221                                 if (!xhci_link_trb_quirk(xhci)) {
222                                         next->link.control &= ~TRB_CHAIN;
223                                         next->link.control |= chain;
224                                 }
225                                 /* Give this link TRB to the hardware */
226                                 wmb();
227                                 next->link.control ^= TRB_CYCLE;
228                         }
229                         /* Toggle the cycle bit after the last ring segment. */
230                         if (last_trb_on_last_seg(xhci, ring, ring->enq_seg, next)) {
231                                 ring->cycle_state = (ring->cycle_state ? 0 : 1);
232                                 if (!in_interrupt())
233                                         xhci_dbg(xhci, "Toggle cycle state for ring %p = %i\n",
234                                                         ring,
235                                                         (unsigned int) ring->cycle_state);
236                         }
237                 }
238                 ring->enq_seg = ring->enq_seg->next;
239                 ring->enqueue = ring->enq_seg->trbs;
240                 next = ring->enqueue;
241         }
242         addr = (unsigned long long) xhci_trb_virt_to_dma(ring->enq_seg, ring->enqueue);
243         if (ring == xhci->event_ring)
244                 xhci_dbg(xhci, "Event ring enq = 0x%llx (DMA)\n", addr);
245         else if (ring == xhci->cmd_ring)
246                 xhci_dbg(xhci, "Command ring enq = 0x%llx (DMA)\n", addr);
247         else
248                 xhci_dbg(xhci, "Ring enq = 0x%llx (DMA)\n", addr);
249 }
250
251 /*
252  * Check to see if there's room to enqueue num_trbs on the ring.  See rules
253  * above.
254  * FIXME: this would be simpler and faster if we just kept track of the number
255  * of free TRBs in a ring.
256  */
257 static int room_on_ring(struct xhci_hcd *xhci, struct xhci_ring *ring,
258                 unsigned int num_trbs)
259 {
260         int i;
261         union xhci_trb *enq = ring->enqueue;
262         struct xhci_segment *enq_seg = ring->enq_seg;
263         struct xhci_segment *cur_seg;
264         unsigned int left_on_ring;
265
266         /* If we are currently pointing to a link TRB, advance the
267          * enqueue pointer before checking for space */
268         while (last_trb(xhci, ring, enq_seg, enq)) {
269                 enq_seg = enq_seg->next;
270                 enq = enq_seg->trbs;
271         }
272
273         /* Check if ring is empty */
274         if (enq == ring->dequeue) {
275                 /* Can't use link trbs */
276                 left_on_ring = TRBS_PER_SEGMENT - 1;
277                 for (cur_seg = enq_seg->next; cur_seg != enq_seg;
278                                 cur_seg = cur_seg->next)
279                         left_on_ring += TRBS_PER_SEGMENT - 1;
280
281                 /* Always need one TRB free in the ring. */
282                 left_on_ring -= 1;
283                 if (num_trbs > left_on_ring) {
284                         xhci_warn(xhci, "Not enough room on ring; "
285                                         "need %u TRBs, %u TRBs left\n",
286                                         num_trbs, left_on_ring);
287                         return 0;
288                 }
289                 return 1;
290         }
291         /* Make sure there's an extra empty TRB available */
292         for (i = 0; i <= num_trbs; ++i) {
293                 if (enq == ring->dequeue)
294                         return 0;
295                 enq++;
296                 while (last_trb(xhci, ring, enq_seg, enq)) {
297                         enq_seg = enq_seg->next;
298                         enq = enq_seg->trbs;
299                 }
300         }
301         return 1;
302 }
303
304 /* Ring the host controller doorbell after placing a command on the ring */
305 void xhci_ring_cmd_db(struct xhci_hcd *xhci)
306 {
307         u32 temp;
308
309         xhci_dbg(xhci, "// Ding dong!\n");
310         temp = xhci_readl(xhci, &xhci->dba->doorbell[0]) & DB_MASK;
311         xhci_writel(xhci, temp | DB_TARGET_HOST, &xhci->dba->doorbell[0]);
312         /* Flush PCI posted writes */
313         xhci_readl(xhci, &xhci->dba->doorbell[0]);
314 }
315
316 static void ring_ep_doorbell(struct xhci_hcd *xhci,
317                 unsigned int slot_id,
318                 unsigned int ep_index,
319                 unsigned int stream_id)
320 {
321         struct xhci_virt_ep *ep;
322         unsigned int ep_state;
323         u32 field;
324         __u32 __iomem *db_addr = &xhci->dba->doorbell[slot_id];
325
326         ep = &xhci->devs[slot_id]->eps[ep_index];
327         ep_state = ep->ep_state;
328         /* Don't ring the doorbell for this endpoint if there are pending
329          * cancellations because the we don't want to interrupt processing.
330          * We don't want to restart any stream rings if there's a set dequeue
331          * pointer command pending because the device can choose to start any
332          * stream once the endpoint is on the HW schedule.
333          * FIXME - check all the stream rings for pending cancellations.
334          */
335         if (!(ep_state & EP_HALT_PENDING) && !(ep_state & SET_DEQ_PENDING)
336                         && !(ep_state & EP_HALTED)) {
337                 field = xhci_readl(xhci, db_addr) & DB_MASK;
338                 field |= EPI_TO_DB(ep_index) | STREAM_ID_TO_DB(stream_id);
339                 xhci_writel(xhci, field, db_addr);
340         }
341 }
342
343 /* Ring the doorbell for any rings with pending URBs */
344 static void ring_doorbell_for_active_rings(struct xhci_hcd *xhci,
345                 unsigned int slot_id,
346                 unsigned int ep_index)
347 {
348         unsigned int stream_id;
349         struct xhci_virt_ep *ep;
350
351         ep = &xhci->devs[slot_id]->eps[ep_index];
352
353         /* A ring has pending URBs if its TD list is not empty */
354         if (!(ep->ep_state & EP_HAS_STREAMS)) {
355                 if (!(list_empty(&ep->ring->td_list)))
356                         ring_ep_doorbell(xhci, slot_id, ep_index, 0);
357                 return;
358         }
359
360         for (stream_id = 1; stream_id < ep->stream_info->num_streams;
361                         stream_id++) {
362                 struct xhci_stream_info *stream_info = ep->stream_info;
363                 if (!list_empty(&stream_info->stream_rings[stream_id]->td_list))
364                         ring_ep_doorbell(xhci, slot_id, ep_index, stream_id);
365         }
366 }
367
368 /*
369  * Find the segment that trb is in.  Start searching in start_seg.
370  * If we must move past a segment that has a link TRB with a toggle cycle state
371  * bit set, then we will toggle the value pointed at by cycle_state.
372  */
373 static struct xhci_segment *find_trb_seg(
374                 struct xhci_segment *start_seg,
375                 union xhci_trb  *trb, int *cycle_state)
376 {
377         struct xhci_segment *cur_seg = start_seg;
378         struct xhci_generic_trb *generic_trb;
379
380         while (cur_seg->trbs > trb ||
381                         &cur_seg->trbs[TRBS_PER_SEGMENT - 1] < trb) {
382                 generic_trb = &cur_seg->trbs[TRBS_PER_SEGMENT - 1].generic;
383                 if ((generic_trb->field[3] & TRB_TYPE_BITMASK) ==
384                                 TRB_TYPE(TRB_LINK) &&
385                                 (generic_trb->field[3] & LINK_TOGGLE))
386                         *cycle_state = ~(*cycle_state) & 0x1;
387                 cur_seg = cur_seg->next;
388                 if (cur_seg == start_seg)
389                         /* Looped over the entire list.  Oops! */
390                         return NULL;
391         }
392         return cur_seg;
393 }
394
395
396 static struct xhci_ring *xhci_triad_to_transfer_ring(struct xhci_hcd *xhci,
397                 unsigned int slot_id, unsigned int ep_index,
398                 unsigned int stream_id)
399 {
400         struct xhci_virt_ep *ep;
401
402         ep = &xhci->devs[slot_id]->eps[ep_index];
403         /* Common case: no streams */
404         if (!(ep->ep_state & EP_HAS_STREAMS))
405                 return ep->ring;
406
407         if (stream_id == 0) {
408                 xhci_warn(xhci,
409                                 "WARN: Slot ID %u, ep index %u has streams, "
410                                 "but URB has no stream ID.\n",
411                                 slot_id, ep_index);
412                 return NULL;
413         }
414
415         if (stream_id < ep->stream_info->num_streams)
416                 return ep->stream_info->stream_rings[stream_id];
417
418         xhci_warn(xhci,
419                         "WARN: Slot ID %u, ep index %u has "
420                         "stream IDs 1 to %u allocated, "
421                         "but stream ID %u is requested.\n",
422                         slot_id, ep_index,
423                         ep->stream_info->num_streams - 1,
424                         stream_id);
425         return NULL;
426 }
427
428 /* Get the right ring for the given URB.
429  * If the endpoint supports streams, boundary check the URB's stream ID.
430  * If the endpoint doesn't support streams, return the singular endpoint ring.
431  */
432 static struct xhci_ring *xhci_urb_to_transfer_ring(struct xhci_hcd *xhci,
433                 struct urb *urb)
434 {
435         return xhci_triad_to_transfer_ring(xhci, urb->dev->slot_id,
436                 xhci_get_endpoint_index(&urb->ep->desc), urb->stream_id);
437 }
438
439 /*
440  * Move the xHC's endpoint ring dequeue pointer past cur_td.
441  * Record the new state of the xHC's endpoint ring dequeue segment,
442  * dequeue pointer, and new consumer cycle state in state.
443  * Update our internal representation of the ring's dequeue pointer.
444  *
445  * We do this in three jumps:
446  *  - First we update our new ring state to be the same as when the xHC stopped.
447  *  - Then we traverse the ring to find the segment that contains
448  *    the last TRB in the TD.  We toggle the xHC's new cycle state when we pass
449  *    any link TRBs with the toggle cycle bit set.
450  *  - Finally we move the dequeue state one TRB further, toggling the cycle bit
451  *    if we've moved it past a link TRB with the toggle cycle bit set.
452  */
453 void xhci_find_new_dequeue_state(struct xhci_hcd *xhci,
454                 unsigned int slot_id, unsigned int ep_index,
455                 unsigned int stream_id, struct xhci_td *cur_td,
456                 struct xhci_dequeue_state *state)
457 {
458         struct xhci_virt_device *dev = xhci->devs[slot_id];
459         struct xhci_ring *ep_ring;
460         struct xhci_generic_trb *trb;
461         struct xhci_ep_ctx *ep_ctx;
462         dma_addr_t addr;
463
464         ep_ring = xhci_triad_to_transfer_ring(xhci, slot_id,
465                         ep_index, stream_id);
466         if (!ep_ring) {
467                 xhci_warn(xhci, "WARN can't find new dequeue state "
468                                 "for invalid stream ID %u.\n",
469                                 stream_id);
470                 return;
471         }
472         state->new_cycle_state = 0;
473         xhci_dbg(xhci, "Finding segment containing stopped TRB.\n");
474         state->new_deq_seg = find_trb_seg(cur_td->start_seg,
475                         dev->eps[ep_index].stopped_trb,
476                         &state->new_cycle_state);
477         if (!state->new_deq_seg)
478                 BUG();
479         /* Dig out the cycle state saved by the xHC during the stop ep cmd */
480         xhci_dbg(xhci, "Finding endpoint context\n");
481         ep_ctx = xhci_get_ep_ctx(xhci, dev->out_ctx, ep_index);
482         state->new_cycle_state = 0x1 & ep_ctx->deq;
483
484         state->new_deq_ptr = cur_td->last_trb;
485         xhci_dbg(xhci, "Finding segment containing last TRB in TD.\n");
486         state->new_deq_seg = find_trb_seg(state->new_deq_seg,
487                         state->new_deq_ptr,
488                         &state->new_cycle_state);
489         if (!state->new_deq_seg)
490                 BUG();
491
492         trb = &state->new_deq_ptr->generic;
493         if ((trb->field[3] & TRB_TYPE_BITMASK) == TRB_TYPE(TRB_LINK) &&
494                                 (trb->field[3] & LINK_TOGGLE))
495                 state->new_cycle_state = ~(state->new_cycle_state) & 0x1;
496         next_trb(xhci, ep_ring, &state->new_deq_seg, &state->new_deq_ptr);
497
498         /* Don't update the ring cycle state for the producer (us). */
499         xhci_dbg(xhci, "New dequeue segment = %p (virtual)\n",
500                         state->new_deq_seg);
501         addr = xhci_trb_virt_to_dma(state->new_deq_seg, state->new_deq_ptr);
502         xhci_dbg(xhci, "New dequeue pointer = 0x%llx (DMA)\n",
503                         (unsigned long long) addr);
504         xhci_dbg(xhci, "Setting dequeue pointer in internal ring state.\n");
505         ep_ring->dequeue = state->new_deq_ptr;
506         ep_ring->deq_seg = state->new_deq_seg;
507 }
508
509 static void td_to_noop(struct xhci_hcd *xhci, struct xhci_ring *ep_ring,
510                 struct xhci_td *cur_td)
511 {
512         struct xhci_segment *cur_seg;
513         union xhci_trb *cur_trb;
514
515         for (cur_seg = cur_td->start_seg, cur_trb = cur_td->first_trb;
516                         true;
517                         next_trb(xhci, ep_ring, &cur_seg, &cur_trb)) {
518                 if ((cur_trb->generic.field[3] & TRB_TYPE_BITMASK) ==
519                                 TRB_TYPE(TRB_LINK)) {
520                         /* Unchain any chained Link TRBs, but
521                          * leave the pointers intact.
522                          */
523                         cur_trb->generic.field[3] &= ~TRB_CHAIN;
524                         xhci_dbg(xhci, "Cancel (unchain) link TRB\n");
525                         xhci_dbg(xhci, "Address = %p (0x%llx dma); "
526                                         "in seg %p (0x%llx dma)\n",
527                                         cur_trb,
528                                         (unsigned long long)xhci_trb_virt_to_dma(cur_seg, cur_trb),
529                                         cur_seg,
530                                         (unsigned long long)cur_seg->dma);
531                 } else {
532                         cur_trb->generic.field[0] = 0;
533                         cur_trb->generic.field[1] = 0;
534                         cur_trb->generic.field[2] = 0;
535                         /* Preserve only the cycle bit of this TRB */
536                         cur_trb->generic.field[3] &= TRB_CYCLE;
537                         cur_trb->generic.field[3] |= TRB_TYPE(TRB_TR_NOOP);
538                         xhci_dbg(xhci, "Cancel TRB %p (0x%llx dma) "
539                                         "in seg %p (0x%llx dma)\n",
540                                         cur_trb,
541                                         (unsigned long long)xhci_trb_virt_to_dma(cur_seg, cur_trb),
542                                         cur_seg,
543                                         (unsigned long long)cur_seg->dma);
544                 }
545                 if (cur_trb == cur_td->last_trb)
546                         break;
547         }
548 }
549
550 static int queue_set_tr_deq(struct xhci_hcd *xhci, int slot_id,
551                 unsigned int ep_index, unsigned int stream_id,
552                 struct xhci_segment *deq_seg,
553                 union xhci_trb *deq_ptr, u32 cycle_state);
554
555 void xhci_queue_new_dequeue_state(struct xhci_hcd *xhci,
556                 unsigned int slot_id, unsigned int ep_index,
557                 unsigned int stream_id,
558                 struct xhci_dequeue_state *deq_state)
559 {
560         struct xhci_virt_ep *ep = &xhci->devs[slot_id]->eps[ep_index];
561
562         xhci_dbg(xhci, "Set TR Deq Ptr cmd, new deq seg = %p (0x%llx dma), "
563                         "new deq ptr = %p (0x%llx dma), new cycle = %u\n",
564                         deq_state->new_deq_seg,
565                         (unsigned long long)deq_state->new_deq_seg->dma,
566                         deq_state->new_deq_ptr,
567                         (unsigned long long)xhci_trb_virt_to_dma(deq_state->new_deq_seg, deq_state->new_deq_ptr),
568                         deq_state->new_cycle_state);
569         queue_set_tr_deq(xhci, slot_id, ep_index, stream_id,
570                         deq_state->new_deq_seg,
571                         deq_state->new_deq_ptr,
572                         (u32) deq_state->new_cycle_state);
573         /* Stop the TD queueing code from ringing the doorbell until
574          * this command completes.  The HC won't set the dequeue pointer
575          * if the ring is running, and ringing the doorbell starts the
576          * ring running.
577          */
578         ep->ep_state |= SET_DEQ_PENDING;
579 }
580
581 static inline void xhci_stop_watchdog_timer_in_irq(struct xhci_hcd *xhci,
582                 struct xhci_virt_ep *ep)
583 {
584         ep->ep_state &= ~EP_HALT_PENDING;
585         /* Can't del_timer_sync in interrupt, so we attempt to cancel.  If the
586          * timer is running on another CPU, we don't decrement stop_cmds_pending
587          * (since we didn't successfully stop the watchdog timer).
588          */
589         if (del_timer(&ep->stop_cmd_timer))
590                 ep->stop_cmds_pending--;
591 }
592
593 /* Must be called with xhci->lock held in interrupt context */
594 static void xhci_giveback_urb_in_irq(struct xhci_hcd *xhci,
595                 struct xhci_td *cur_td, int status, char *adjective)
596 {
597         struct usb_hcd *hcd = xhci_to_hcd(xhci);
598         struct urb      *urb;
599         struct urb_priv *urb_priv;
600
601         urb = cur_td->urb;
602         urb_priv = urb->hcpriv;
603         urb_priv->td_cnt++;
604
605         /* Only giveback urb when this is the last td in urb */
606         if (urb_priv->td_cnt == urb_priv->length) {
607                 usb_hcd_unlink_urb_from_ep(hcd, urb);
608                 xhci_dbg(xhci, "Giveback %s URB %p\n", adjective, urb);
609
610                 spin_unlock(&xhci->lock);
611                 usb_hcd_giveback_urb(hcd, urb, status);
612                 xhci_urb_free_priv(xhci, urb_priv);
613                 spin_lock(&xhci->lock);
614                 xhci_dbg(xhci, "%s URB given back\n", adjective);
615         }
616 }
617
618 /*
619  * When we get a command completion for a Stop Endpoint Command, we need to
620  * unlink any cancelled TDs from the ring.  There are two ways to do that:
621  *
622  *  1. If the HW was in the middle of processing the TD that needs to be
623  *     cancelled, then we must move the ring's dequeue pointer past the last TRB
624  *     in the TD with a Set Dequeue Pointer Command.
625  *  2. Otherwise, we turn all the TRBs in the TD into No-op TRBs (with the chain
626  *     bit cleared) so that the HW will skip over them.
627  */
628 static void handle_stopped_endpoint(struct xhci_hcd *xhci,
629                 union xhci_trb *trb)
630 {
631         unsigned int slot_id;
632         unsigned int ep_index;
633         struct xhci_ring *ep_ring;
634         struct xhci_virt_ep *ep;
635         struct list_head *entry;
636         struct xhci_td *cur_td = NULL;
637         struct xhci_td *last_unlinked_td;
638
639         struct xhci_dequeue_state deq_state;
640
641         memset(&deq_state, 0, sizeof(deq_state));
642         slot_id = TRB_TO_SLOT_ID(trb->generic.field[3]);
643         ep_index = TRB_TO_EP_INDEX(trb->generic.field[3]);
644         ep = &xhci->devs[slot_id]->eps[ep_index];
645
646         if (list_empty(&ep->cancelled_td_list)) {
647                 xhci_stop_watchdog_timer_in_irq(xhci, ep);
648                 ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
649                 return;
650         }
651
652         /* Fix up the ep ring first, so HW stops executing cancelled TDs.
653          * We have the xHCI lock, so nothing can modify this list until we drop
654          * it.  We're also in the event handler, so we can't get re-interrupted
655          * if another Stop Endpoint command completes
656          */
657         list_for_each(entry, &ep->cancelled_td_list) {
658                 cur_td = list_entry(entry, struct xhci_td, cancelled_td_list);
659                 xhci_dbg(xhci, "Cancelling TD starting at %p, 0x%llx (dma).\n",
660                                 cur_td->first_trb,
661                                 (unsigned long long)xhci_trb_virt_to_dma(cur_td->start_seg, cur_td->first_trb));
662                 ep_ring = xhci_urb_to_transfer_ring(xhci, cur_td->urb);
663                 if (!ep_ring) {
664                         /* This shouldn't happen unless a driver is mucking
665                          * with the stream ID after submission.  This will
666                          * leave the TD on the hardware ring, and the hardware
667                          * will try to execute it, and may access a buffer
668                          * that has already been freed.  In the best case, the
669                          * hardware will execute it, and the event handler will
670                          * ignore the completion event for that TD, since it was
671                          * removed from the td_list for that endpoint.  In
672                          * short, don't muck with the stream ID after
673                          * submission.
674                          */
675                         xhci_warn(xhci, "WARN Cancelled URB %p "
676                                         "has invalid stream ID %u.\n",
677                                         cur_td->urb,
678                                         cur_td->urb->stream_id);
679                         goto remove_finished_td;
680                 }
681                 /*
682                  * If we stopped on the TD we need to cancel, then we have to
683                  * move the xHC endpoint ring dequeue pointer past this TD.
684                  */
685                 if (cur_td == ep->stopped_td)
686                         xhci_find_new_dequeue_state(xhci, slot_id, ep_index,
687                                         cur_td->urb->stream_id,
688                                         cur_td, &deq_state);
689                 else
690                         td_to_noop(xhci, ep_ring, cur_td);
691 remove_finished_td:
692                 /*
693                  * The event handler won't see a completion for this TD anymore,
694                  * so remove it from the endpoint ring's TD list.  Keep it in
695                  * the cancelled TD list for URB completion later.
696                  */
697                 list_del(&cur_td->td_list);
698         }
699         last_unlinked_td = cur_td;
700         xhci_stop_watchdog_timer_in_irq(xhci, ep);
701
702         /* If necessary, queue a Set Transfer Ring Dequeue Pointer command */
703         if (deq_state.new_deq_ptr && deq_state.new_deq_seg) {
704                 xhci_queue_new_dequeue_state(xhci,
705                                 slot_id, ep_index,
706                                 ep->stopped_td->urb->stream_id,
707                                 &deq_state);
708                 xhci_ring_cmd_db(xhci);
709         } else {
710                 /* Otherwise ring the doorbell(s) to restart queued transfers */
711                 ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
712         }
713         ep->stopped_td = NULL;
714         ep->stopped_trb = NULL;
715
716         /*
717          * Drop the lock and complete the URBs in the cancelled TD list.
718          * New TDs to be cancelled might be added to the end of the list before
719          * we can complete all the URBs for the TDs we already unlinked.
720          * So stop when we've completed the URB for the last TD we unlinked.
721          */
722         do {
723                 cur_td = list_entry(ep->cancelled_td_list.next,
724                                 struct xhci_td, cancelled_td_list);
725                 list_del(&cur_td->cancelled_td_list);
726
727                 /* Clean up the cancelled URB */
728                 /* Doesn't matter what we pass for status, since the core will
729                  * just overwrite it (because the URB has been unlinked).
730                  */
731                 xhci_giveback_urb_in_irq(xhci, cur_td, 0, "cancelled");
732
733                 /* Stop processing the cancelled list if the watchdog timer is
734                  * running.
735                  */
736                 if (xhci->xhc_state & XHCI_STATE_DYING)
737                         return;
738         } while (cur_td != last_unlinked_td);
739
740         /* Return to the event handler with xhci->lock re-acquired */
741 }
742
743 /* Watchdog timer function for when a stop endpoint command fails to complete.
744  * In this case, we assume the host controller is broken or dying or dead.  The
745  * host may still be completing some other events, so we have to be careful to
746  * let the event ring handler and the URB dequeueing/enqueueing functions know
747  * through xhci->state.
748  *
749  * The timer may also fire if the host takes a very long time to respond to the
750  * command, and the stop endpoint command completion handler cannot delete the
751  * timer before the timer function is called.  Another endpoint cancellation may
752  * sneak in before the timer function can grab the lock, and that may queue
753  * another stop endpoint command and add the timer back.  So we cannot use a
754  * simple flag to say whether there is a pending stop endpoint command for a
755  * particular endpoint.
756  *
757  * Instead we use a combination of that flag and a counter for the number of
758  * pending stop endpoint commands.  If the timer is the tail end of the last
759  * stop endpoint command, and the endpoint's command is still pending, we assume
760  * the host is dying.
761  */
762 void xhci_stop_endpoint_command_watchdog(unsigned long arg)
763 {
764         struct xhci_hcd *xhci;
765         struct xhci_virt_ep *ep;
766         struct xhci_virt_ep *temp_ep;
767         struct xhci_ring *ring;
768         struct xhci_td *cur_td;
769         int ret, i, j;
770
771         ep = (struct xhci_virt_ep *) arg;
772         xhci = ep->xhci;
773
774         spin_lock(&xhci->lock);
775
776         ep->stop_cmds_pending--;
777         if (xhci->xhc_state & XHCI_STATE_DYING) {
778                 xhci_dbg(xhci, "Stop EP timer ran, but another timer marked "
779                                 "xHCI as DYING, exiting.\n");
780                 spin_unlock(&xhci->lock);
781                 return;
782         }
783         if (!(ep->stop_cmds_pending == 0 && (ep->ep_state & EP_HALT_PENDING))) {
784                 xhci_dbg(xhci, "Stop EP timer ran, but no command pending, "
785                                 "exiting.\n");
786                 spin_unlock(&xhci->lock);
787                 return;
788         }
789
790         xhci_warn(xhci, "xHCI host not responding to stop endpoint command.\n");
791         xhci_warn(xhci, "Assuming host is dying, halting host.\n");
792         /* Oops, HC is dead or dying or at least not responding to the stop
793          * endpoint command.
794          */
795         xhci->xhc_state |= XHCI_STATE_DYING;
796         /* Disable interrupts from the host controller and start halting it */
797         xhci_quiesce(xhci);
798         spin_unlock(&xhci->lock);
799
800         ret = xhci_halt(xhci);
801
802         spin_lock(&xhci->lock);
803         if (ret < 0) {
804                 /* This is bad; the host is not responding to commands and it's
805                  * not allowing itself to be halted.  At least interrupts are
806                  * disabled, so we can set HC_STATE_HALT and notify the
807                  * USB core.  But if we call usb_hc_died(), it will attempt to
808                  * disconnect all device drivers under this host.  Those
809                  * disconnect() methods will wait for all URBs to be unlinked,
810                  * so we must complete them.
811                  */
812                 xhci_warn(xhci, "Non-responsive xHCI host is not halting.\n");
813                 xhci_warn(xhci, "Completing active URBs anyway.\n");
814                 /* We could turn all TDs on the rings to no-ops.  This won't
815                  * help if the host has cached part of the ring, and is slow if
816                  * we want to preserve the cycle bit.  Skip it and hope the host
817                  * doesn't touch the memory.
818                  */
819         }
820         for (i = 0; i < MAX_HC_SLOTS; i++) {
821                 if (!xhci->devs[i])
822                         continue;
823                 for (j = 0; j < 31; j++) {
824                         temp_ep = &xhci->devs[i]->eps[j];
825                         ring = temp_ep->ring;
826                         if (!ring)
827                                 continue;
828                         xhci_dbg(xhci, "Killing URBs for slot ID %u, "
829                                         "ep index %u\n", i, j);
830                         while (!list_empty(&ring->td_list)) {
831                                 cur_td = list_first_entry(&ring->td_list,
832                                                 struct xhci_td,
833                                                 td_list);
834                                 list_del(&cur_td->td_list);
835                                 if (!list_empty(&cur_td->cancelled_td_list))
836                                         list_del(&cur_td->cancelled_td_list);
837                                 xhci_giveback_urb_in_irq(xhci, cur_td,
838                                                 -ESHUTDOWN, "killed");
839                         }
840                         while (!list_empty(&temp_ep->cancelled_td_list)) {
841                                 cur_td = list_first_entry(
842                                                 &temp_ep->cancelled_td_list,
843                                                 struct xhci_td,
844                                                 cancelled_td_list);
845                                 list_del(&cur_td->cancelled_td_list);
846                                 xhci_giveback_urb_in_irq(xhci, cur_td,
847                                                 -ESHUTDOWN, "killed");
848                         }
849                 }
850         }
851         spin_unlock(&xhci->lock);
852         xhci_to_hcd(xhci)->state = HC_STATE_HALT;
853         xhci_dbg(xhci, "Calling usb_hc_died()\n");
854         usb_hc_died(xhci_to_hcd(xhci));
855         xhci_dbg(xhci, "xHCI host controller is dead.\n");
856 }
857
858 /*
859  * When we get a completion for a Set Transfer Ring Dequeue Pointer command,
860  * we need to clear the set deq pending flag in the endpoint ring state, so that
861  * the TD queueing code can ring the doorbell again.  We also need to ring the
862  * endpoint doorbell to restart the ring, but only if there aren't more
863  * cancellations pending.
864  */
865 static void handle_set_deq_completion(struct xhci_hcd *xhci,
866                 struct xhci_event_cmd *event,
867                 union xhci_trb *trb)
868 {
869         unsigned int slot_id;
870         unsigned int ep_index;
871         unsigned int stream_id;
872         struct xhci_ring *ep_ring;
873         struct xhci_virt_device *dev;
874         struct xhci_ep_ctx *ep_ctx;
875         struct xhci_slot_ctx *slot_ctx;
876
877         slot_id = TRB_TO_SLOT_ID(trb->generic.field[3]);
878         ep_index = TRB_TO_EP_INDEX(trb->generic.field[3]);
879         stream_id = TRB_TO_STREAM_ID(trb->generic.field[2]);
880         dev = xhci->devs[slot_id];
881
882         ep_ring = xhci_stream_id_to_ring(dev, ep_index, stream_id);
883         if (!ep_ring) {
884                 xhci_warn(xhci, "WARN Set TR deq ptr command for "
885                                 "freed stream ID %u\n",
886                                 stream_id);
887                 /* XXX: Harmless??? */
888                 dev->eps[ep_index].ep_state &= ~SET_DEQ_PENDING;
889                 return;
890         }
891
892         ep_ctx = xhci_get_ep_ctx(xhci, dev->out_ctx, ep_index);
893         slot_ctx = xhci_get_slot_ctx(xhci, dev->out_ctx);
894
895         if (GET_COMP_CODE(event->status) != COMP_SUCCESS) {
896                 unsigned int ep_state;
897                 unsigned int slot_state;
898
899                 switch (GET_COMP_CODE(event->status)) {
900                 case COMP_TRB_ERR:
901                         xhci_warn(xhci, "WARN Set TR Deq Ptr cmd invalid because "
902                                         "of stream ID configuration\n");
903                         break;
904                 case COMP_CTX_STATE:
905                         xhci_warn(xhci, "WARN Set TR Deq Ptr cmd failed due "
906                                         "to incorrect slot or ep state.\n");
907                         ep_state = ep_ctx->ep_info;
908                         ep_state &= EP_STATE_MASK;
909                         slot_state = slot_ctx->dev_state;
910                         slot_state = GET_SLOT_STATE(slot_state);
911                         xhci_dbg(xhci, "Slot state = %u, EP state = %u\n",
912                                         slot_state, ep_state);
913                         break;
914                 case COMP_EBADSLT:
915                         xhci_warn(xhci, "WARN Set TR Deq Ptr cmd failed because "
916                                         "slot %u was not enabled.\n", slot_id);
917                         break;
918                 default:
919                         xhci_warn(xhci, "WARN Set TR Deq Ptr cmd with unknown "
920                                         "completion code of %u.\n",
921                                         GET_COMP_CODE(event->status));
922                         break;
923                 }
924                 /* OK what do we do now?  The endpoint state is hosed, and we
925                  * should never get to this point if the synchronization between
926                  * queueing, and endpoint state are correct.  This might happen
927                  * if the device gets disconnected after we've finished
928                  * cancelling URBs, which might not be an error...
929                  */
930         } else {
931                 xhci_dbg(xhci, "Successful Set TR Deq Ptr cmd, deq = @%08llx\n",
932                                 ep_ctx->deq);
933         }
934
935         dev->eps[ep_index].ep_state &= ~SET_DEQ_PENDING;
936         /* Restart any rings with pending URBs */
937         ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
938 }
939
940 static void handle_reset_ep_completion(struct xhci_hcd *xhci,
941                 struct xhci_event_cmd *event,
942                 union xhci_trb *trb)
943 {
944         int slot_id;
945         unsigned int ep_index;
946
947         slot_id = TRB_TO_SLOT_ID(trb->generic.field[3]);
948         ep_index = TRB_TO_EP_INDEX(trb->generic.field[3]);
949         /* This command will only fail if the endpoint wasn't halted,
950          * but we don't care.
951          */
952         xhci_dbg(xhci, "Ignoring reset ep completion code of %u\n",
953                         (unsigned int) GET_COMP_CODE(event->status));
954
955         /* HW with the reset endpoint quirk needs to have a configure endpoint
956          * command complete before the endpoint can be used.  Queue that here
957          * because the HW can't handle two commands being queued in a row.
958          */
959         if (xhci->quirks & XHCI_RESET_EP_QUIRK) {
960                 xhci_dbg(xhci, "Queueing configure endpoint command\n");
961                 xhci_queue_configure_endpoint(xhci,
962                                 xhci->devs[slot_id]->in_ctx->dma, slot_id,
963                                 false);
964                 xhci_ring_cmd_db(xhci);
965         } else {
966                 /* Clear our internal halted state and restart the ring(s) */
967                 xhci->devs[slot_id]->eps[ep_index].ep_state &= ~EP_HALTED;
968                 ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
969         }
970 }
971
972 /* Check to see if a command in the device's command queue matches this one.
973  * Signal the completion or free the command, and return 1.  Return 0 if the
974  * completed command isn't at the head of the command list.
975  */
976 static int handle_cmd_in_cmd_wait_list(struct xhci_hcd *xhci,
977                 struct xhci_virt_device *virt_dev,
978                 struct xhci_event_cmd *event)
979 {
980         struct xhci_command *command;
981
982         if (list_empty(&virt_dev->cmd_list))
983                 return 0;
984
985         command = list_entry(virt_dev->cmd_list.next,
986                         struct xhci_command, cmd_list);
987         if (xhci->cmd_ring->dequeue != command->command_trb)
988                 return 0;
989
990         command->status =
991                 GET_COMP_CODE(event->status);
992         list_del(&command->cmd_list);
993         if (command->completion)
994                 complete(command->completion);
995         else
996                 xhci_free_command(xhci, command);
997         return 1;
998 }
999
1000 static void handle_cmd_completion(struct xhci_hcd *xhci,
1001                 struct xhci_event_cmd *event)
1002 {
1003         int slot_id = TRB_TO_SLOT_ID(event->flags);
1004         u64 cmd_dma;
1005         dma_addr_t cmd_dequeue_dma;
1006         struct xhci_input_control_ctx *ctrl_ctx;
1007         struct xhci_virt_device *virt_dev;
1008         unsigned int ep_index;
1009         struct xhci_ring *ep_ring;
1010         unsigned int ep_state;
1011
1012         cmd_dma = event->cmd_trb;
1013         cmd_dequeue_dma = xhci_trb_virt_to_dma(xhci->cmd_ring->deq_seg,
1014                         xhci->cmd_ring->dequeue);
1015         /* Is the command ring deq ptr out of sync with the deq seg ptr? */
1016         if (cmd_dequeue_dma == 0) {
1017                 xhci->error_bitmask |= 1 << 4;
1018                 return;
1019         }
1020         /* Does the DMA address match our internal dequeue pointer address? */
1021         if (cmd_dma != (u64) cmd_dequeue_dma) {
1022                 xhci->error_bitmask |= 1 << 5;
1023                 return;
1024         }
1025         switch (xhci->cmd_ring->dequeue->generic.field[3] & TRB_TYPE_BITMASK) {
1026         case TRB_TYPE(TRB_ENABLE_SLOT):
1027                 if (GET_COMP_CODE(event->status) == COMP_SUCCESS)
1028                         xhci->slot_id = slot_id;
1029                 else
1030                         xhci->slot_id = 0;
1031                 complete(&xhci->addr_dev);
1032                 break;
1033         case TRB_TYPE(TRB_DISABLE_SLOT):
1034                 if (xhci->devs[slot_id])
1035                         xhci_free_virt_device(xhci, slot_id);
1036                 break;
1037         case TRB_TYPE(TRB_CONFIG_EP):
1038                 virt_dev = xhci->devs[slot_id];
1039                 if (handle_cmd_in_cmd_wait_list(xhci, virt_dev, event))
1040                         break;
1041                 /*
1042                  * Configure endpoint commands can come from the USB core
1043                  * configuration or alt setting changes, or because the HW
1044                  * needed an extra configure endpoint command after a reset
1045                  * endpoint command or streams were being configured.
1046                  * If the command was for a halted endpoint, the xHCI driver
1047                  * is not waiting on the configure endpoint command.
1048                  */
1049                 ctrl_ctx = xhci_get_input_control_ctx(xhci,
1050                                 virt_dev->in_ctx);
1051                 /* Input ctx add_flags are the endpoint index plus one */
1052                 ep_index = xhci_last_valid_endpoint(ctrl_ctx->add_flags) - 1;
1053                 /* A usb_set_interface() call directly after clearing a halted
1054                  * condition may race on this quirky hardware.  Not worth
1055                  * worrying about, since this is prototype hardware.  Not sure
1056                  * if this will work for streams, but streams support was
1057                  * untested on this prototype.
1058                  */
1059                 if (xhci->quirks & XHCI_RESET_EP_QUIRK &&
1060                                 ep_index != (unsigned int) -1 &&
1061                                 ctrl_ctx->add_flags - SLOT_FLAG ==
1062                                         ctrl_ctx->drop_flags) {
1063                         ep_ring = xhci->devs[slot_id]->eps[ep_index].ring;
1064                         ep_state = xhci->devs[slot_id]->eps[ep_index].ep_state;
1065                         if (!(ep_state & EP_HALTED))
1066                                 goto bandwidth_change;
1067                         xhci_dbg(xhci, "Completed config ep cmd - "
1068                                         "last ep index = %d, state = %d\n",
1069                                         ep_index, ep_state);
1070                         /* Clear internal halted state and restart ring(s) */
1071                         xhci->devs[slot_id]->eps[ep_index].ep_state &=
1072                                 ~EP_HALTED;
1073                         ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
1074                         break;
1075                 }
1076 bandwidth_change:
1077                 xhci_dbg(xhci, "Completed config ep cmd\n");
1078                 xhci->devs[slot_id]->cmd_status =
1079                         GET_COMP_CODE(event->status);
1080                 complete(&xhci->devs[slot_id]->cmd_completion);
1081                 break;
1082         case TRB_TYPE(TRB_EVAL_CONTEXT):
1083                 virt_dev = xhci->devs[slot_id];
1084                 if (handle_cmd_in_cmd_wait_list(xhci, virt_dev, event))
1085                         break;
1086                 xhci->devs[slot_id]->cmd_status = GET_COMP_CODE(event->status);
1087                 complete(&xhci->devs[slot_id]->cmd_completion);
1088                 break;
1089         case TRB_TYPE(TRB_ADDR_DEV):
1090                 xhci->devs[slot_id]->cmd_status = GET_COMP_CODE(event->status);
1091                 complete(&xhci->addr_dev);
1092                 break;
1093         case TRB_TYPE(TRB_STOP_RING):
1094                 handle_stopped_endpoint(xhci, xhci->cmd_ring->dequeue);
1095                 break;
1096         case TRB_TYPE(TRB_SET_DEQ):
1097                 handle_set_deq_completion(xhci, event, xhci->cmd_ring->dequeue);
1098                 break;
1099         case TRB_TYPE(TRB_CMD_NOOP):
1100                 ++xhci->noops_handled;
1101                 break;
1102         case TRB_TYPE(TRB_RESET_EP):
1103                 handle_reset_ep_completion(xhci, event, xhci->cmd_ring->dequeue);
1104                 break;
1105         case TRB_TYPE(TRB_RESET_DEV):
1106                 xhci_dbg(xhci, "Completed reset device command.\n");
1107                 slot_id = TRB_TO_SLOT_ID(
1108                                 xhci->cmd_ring->dequeue->generic.field[3]);
1109                 virt_dev = xhci->devs[slot_id];
1110                 if (virt_dev)
1111                         handle_cmd_in_cmd_wait_list(xhci, virt_dev, event);
1112                 else
1113                         xhci_warn(xhci, "Reset device command completion "
1114                                         "for disabled slot %u\n", slot_id);
1115                 break;
1116         case TRB_TYPE(TRB_NEC_GET_FW):
1117                 if (!(xhci->quirks & XHCI_NEC_HOST)) {
1118                         xhci->error_bitmask |= 1 << 6;
1119                         break;
1120                 }
1121                 xhci_dbg(xhci, "NEC firmware version %2x.%02x\n",
1122                                 NEC_FW_MAJOR(event->status),
1123                                 NEC_FW_MINOR(event->status));
1124                 break;
1125         default:
1126                 /* Skip over unknown commands on the event ring */
1127                 xhci->error_bitmask |= 1 << 6;
1128                 break;
1129         }
1130         inc_deq(xhci, xhci->cmd_ring, false);
1131 }
1132
1133 static void handle_vendor_event(struct xhci_hcd *xhci,
1134                 union xhci_trb *event)
1135 {
1136         u32 trb_type;
1137
1138         trb_type = TRB_FIELD_TO_TYPE(event->generic.field[3]);
1139         xhci_dbg(xhci, "Vendor specific event TRB type = %u\n", trb_type);
1140         if (trb_type == TRB_NEC_CMD_COMP && (xhci->quirks & XHCI_NEC_HOST))
1141                 handle_cmd_completion(xhci, &event->event_cmd);
1142 }
1143
1144 static void handle_port_status(struct xhci_hcd *xhci,
1145                 union xhci_trb *event)
1146 {
1147         u32 port_id;
1148
1149         /* Port status change events always have a successful completion code */
1150         if (GET_COMP_CODE(event->generic.field[2]) != COMP_SUCCESS) {
1151                 xhci_warn(xhci, "WARN: xHC returned failed port status event\n");
1152                 xhci->error_bitmask |= 1 << 8;
1153         }
1154         /* FIXME: core doesn't care about all port link state changes yet */
1155         port_id = GET_PORT_ID(event->generic.field[0]);
1156         xhci_dbg(xhci, "Port Status Change Event for port %d\n", port_id);
1157
1158         /* Update event ring dequeue pointer before dropping the lock */
1159         inc_deq(xhci, xhci->event_ring, true);
1160
1161         spin_unlock(&xhci->lock);
1162         /* Pass this up to the core */
1163         usb_hcd_poll_rh_status(xhci_to_hcd(xhci));
1164         spin_lock(&xhci->lock);
1165 }
1166
1167 /*
1168  * This TD is defined by the TRBs starting at start_trb in start_seg and ending
1169  * at end_trb, which may be in another segment.  If the suspect DMA address is a
1170  * TRB in this TD, this function returns that TRB's segment.  Otherwise it
1171  * returns 0.
1172  */
1173 struct xhci_segment *trb_in_td(struct xhci_segment *start_seg,
1174                 union xhci_trb  *start_trb,
1175                 union xhci_trb  *end_trb,
1176                 dma_addr_t      suspect_dma)
1177 {
1178         dma_addr_t start_dma;
1179         dma_addr_t end_seg_dma;
1180         dma_addr_t end_trb_dma;
1181         struct xhci_segment *cur_seg;
1182
1183         start_dma = xhci_trb_virt_to_dma(start_seg, start_trb);
1184         cur_seg = start_seg;
1185
1186         do {
1187                 if (start_dma == 0)
1188                         return NULL;
1189                 /* We may get an event for a Link TRB in the middle of a TD */
1190                 end_seg_dma = xhci_trb_virt_to_dma(cur_seg,
1191                                 &cur_seg->trbs[TRBS_PER_SEGMENT - 1]);
1192                 /* If the end TRB isn't in this segment, this is set to 0 */
1193                 end_trb_dma = xhci_trb_virt_to_dma(cur_seg, end_trb);
1194
1195                 if (end_trb_dma > 0) {
1196                         /* The end TRB is in this segment, so suspect should be here */
1197                         if (start_dma <= end_trb_dma) {
1198                                 if (suspect_dma >= start_dma && suspect_dma <= end_trb_dma)
1199                                         return cur_seg;
1200                         } else {
1201                                 /* Case for one segment with
1202                                  * a TD wrapped around to the top
1203                                  */
1204                                 if ((suspect_dma >= start_dma &&
1205                                                         suspect_dma <= end_seg_dma) ||
1206                                                 (suspect_dma >= cur_seg->dma &&
1207                                                  suspect_dma <= end_trb_dma))
1208                                         return cur_seg;
1209                         }
1210                         return NULL;
1211                 } else {
1212                         /* Might still be somewhere in this segment */
1213                         if (suspect_dma >= start_dma && suspect_dma <= end_seg_dma)
1214                                 return cur_seg;
1215                 }
1216                 cur_seg = cur_seg->next;
1217                 start_dma = xhci_trb_virt_to_dma(cur_seg, &cur_seg->trbs[0]);
1218         } while (cur_seg != start_seg);
1219
1220         return NULL;
1221 }
1222
1223 static void xhci_cleanup_halted_endpoint(struct xhci_hcd *xhci,
1224                 unsigned int slot_id, unsigned int ep_index,
1225                 unsigned int stream_id,
1226                 struct xhci_td *td, union xhci_trb *event_trb)
1227 {
1228         struct xhci_virt_ep *ep = &xhci->devs[slot_id]->eps[ep_index];
1229         ep->ep_state |= EP_HALTED;
1230         ep->stopped_td = td;
1231         ep->stopped_trb = event_trb;
1232         ep->stopped_stream = stream_id;
1233
1234         xhci_queue_reset_ep(xhci, slot_id, ep_index);
1235         xhci_cleanup_stalled_ring(xhci, td->urb->dev, ep_index);
1236
1237         ep->stopped_td = NULL;
1238         ep->stopped_trb = NULL;
1239         ep->stopped_stream = 0;
1240
1241         xhci_ring_cmd_db(xhci);
1242 }
1243
1244 /* Check if an error has halted the endpoint ring.  The class driver will
1245  * cleanup the halt for a non-default control endpoint if we indicate a stall.
1246  * However, a babble and other errors also halt the endpoint ring, and the class
1247  * driver won't clear the halt in that case, so we need to issue a Set Transfer
1248  * Ring Dequeue Pointer command manually.
1249  */
1250 static int xhci_requires_manual_halt_cleanup(struct xhci_hcd *xhci,
1251                 struct xhci_ep_ctx *ep_ctx,
1252                 unsigned int trb_comp_code)
1253 {
1254         /* TRB completion codes that may require a manual halt cleanup */
1255         if (trb_comp_code == COMP_TX_ERR ||
1256                         trb_comp_code == COMP_BABBLE ||
1257                         trb_comp_code == COMP_SPLIT_ERR)
1258                 /* The 0.96 spec says a babbling control endpoint
1259                  * is not halted. The 0.96 spec says it is.  Some HW
1260                  * claims to be 0.95 compliant, but it halts the control
1261                  * endpoint anyway.  Check if a babble halted the
1262                  * endpoint.
1263                  */
1264                 if ((ep_ctx->ep_info & EP_STATE_MASK) == EP_STATE_HALTED)
1265                         return 1;
1266
1267         return 0;
1268 }
1269
1270 int xhci_is_vendor_info_code(struct xhci_hcd *xhci, unsigned int trb_comp_code)
1271 {
1272         if (trb_comp_code >= 224 && trb_comp_code <= 255) {
1273                 /* Vendor defined "informational" completion code,
1274                  * treat as not-an-error.
1275                  */
1276                 xhci_dbg(xhci, "Vendor defined info completion code %u\n",
1277                                 trb_comp_code);
1278                 xhci_dbg(xhci, "Treating code as success.\n");
1279                 return 1;
1280         }
1281         return 0;
1282 }
1283
1284 /*
1285  * Finish the td processing, remove the td from td list;
1286  * Return 1 if the urb can be given back.
1287  */
1288 static int finish_td(struct xhci_hcd *xhci, struct xhci_td *td,
1289         union xhci_trb *event_trb, struct xhci_transfer_event *event,
1290         struct xhci_virt_ep *ep, int *status, bool skip)
1291 {
1292         struct xhci_virt_device *xdev;
1293         struct xhci_ring *ep_ring;
1294         unsigned int slot_id;
1295         int ep_index;
1296         struct urb *urb = NULL;
1297         struct xhci_ep_ctx *ep_ctx;
1298         int ret = 0;
1299         struct urb_priv *urb_priv;
1300         u32 trb_comp_code;
1301
1302         slot_id = TRB_TO_SLOT_ID(event->flags);
1303         xdev = xhci->devs[slot_id];
1304         ep_index = TRB_TO_EP_ID(event->flags) - 1;
1305         ep_ring = xhci_dma_to_transfer_ring(ep, event->buffer);
1306         ep_ctx = xhci_get_ep_ctx(xhci, xdev->out_ctx, ep_index);
1307         trb_comp_code = GET_COMP_CODE(event->transfer_len);
1308
1309         if (skip)
1310                 goto td_cleanup;
1311
1312         if (trb_comp_code == COMP_STOP_INVAL ||
1313                         trb_comp_code == COMP_STOP) {
1314                 /* The Endpoint Stop Command completion will take care of any
1315                  * stopped TDs.  A stopped TD may be restarted, so don't update
1316                  * the ring dequeue pointer or take this TD off any lists yet.
1317                  */
1318                 ep->stopped_td = td;
1319                 ep->stopped_trb = event_trb;
1320                 return 0;
1321         } else {
1322                 if (trb_comp_code == COMP_STALL) {
1323                         /* The transfer is completed from the driver's
1324                          * perspective, but we need to issue a set dequeue
1325                          * command for this stalled endpoint to move the dequeue
1326                          * pointer past the TD.  We can't do that here because
1327                          * the halt condition must be cleared first.  Let the
1328                          * USB class driver clear the stall later.
1329                          */
1330                         ep->stopped_td = td;
1331                         ep->stopped_trb = event_trb;
1332                         ep->stopped_stream = ep_ring->stream_id;
1333                 } else if (xhci_requires_manual_halt_cleanup(xhci,
1334                                         ep_ctx, trb_comp_code)) {
1335                         /* Other types of errors halt the endpoint, but the
1336                          * class driver doesn't call usb_reset_endpoint() unless
1337                          * the error is -EPIPE.  Clear the halted status in the
1338                          * xHCI hardware manually.
1339                          */
1340                         xhci_cleanup_halted_endpoint(xhci,
1341                                         slot_id, ep_index, ep_ring->stream_id,
1342                                         td, event_trb);
1343                 } else {
1344                         /* Update ring dequeue pointer */
1345                         while (ep_ring->dequeue != td->last_trb)
1346                                 inc_deq(xhci, ep_ring, false);
1347                         inc_deq(xhci, ep_ring, false);
1348                 }
1349
1350 td_cleanup:
1351                 /* Clean up the endpoint's TD list */
1352                 urb = td->urb;
1353                 urb_priv = urb->hcpriv;
1354
1355                 /* Do one last check of the actual transfer length.
1356                  * If the host controller said we transferred more data than
1357                  * the buffer length, urb->actual_length will be a very big
1358                  * number (since it's unsigned).  Play it safe and say we didn't
1359                  * transfer anything.
1360                  */
1361                 if (urb->actual_length > urb->transfer_buffer_length) {
1362                         xhci_warn(xhci, "URB transfer length is wrong, "
1363                                         "xHC issue? req. len = %u, "
1364                                         "act. len = %u\n",
1365                                         urb->transfer_buffer_length,
1366                                         urb->actual_length);
1367                         urb->actual_length = 0;
1368                         if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
1369                                 *status = -EREMOTEIO;
1370                         else
1371                                 *status = 0;
1372                 }
1373                 list_del(&td->td_list);
1374                 /* Was this TD slated to be cancelled but completed anyway? */
1375                 if (!list_empty(&td->cancelled_td_list))
1376                         list_del(&td->cancelled_td_list);
1377
1378                 urb_priv->td_cnt++;
1379                 /* Giveback the urb when all the tds are completed */
1380                 if (urb_priv->td_cnt == urb_priv->length)
1381                         ret = 1;
1382         }
1383
1384         return ret;
1385 }
1386
1387 /*
1388  * Process control tds, update urb status and actual_length.
1389  */
1390 static int process_ctrl_td(struct xhci_hcd *xhci, struct xhci_td *td,
1391         union xhci_trb *event_trb, struct xhci_transfer_event *event,
1392         struct xhci_virt_ep *ep, int *status)
1393 {
1394         struct xhci_virt_device *xdev;
1395         struct xhci_ring *ep_ring;
1396         unsigned int slot_id;
1397         int ep_index;
1398         struct xhci_ep_ctx *ep_ctx;
1399         u32 trb_comp_code;
1400
1401         slot_id = TRB_TO_SLOT_ID(event->flags);
1402         xdev = xhci->devs[slot_id];
1403         ep_index = TRB_TO_EP_ID(event->flags) - 1;
1404         ep_ring = xhci_dma_to_transfer_ring(ep, event->buffer);
1405         ep_ctx = xhci_get_ep_ctx(xhci, xdev->out_ctx, ep_index);
1406         trb_comp_code = GET_COMP_CODE(event->transfer_len);
1407
1408         xhci_debug_trb(xhci, xhci->event_ring->dequeue);
1409         switch (trb_comp_code) {
1410         case COMP_SUCCESS:
1411                 if (event_trb == ep_ring->dequeue) {
1412                         xhci_warn(xhci, "WARN: Success on ctrl setup TRB "
1413                                         "without IOC set??\n");
1414                         *status = -ESHUTDOWN;
1415                 } else if (event_trb != td->last_trb) {
1416                         xhci_warn(xhci, "WARN: Success on ctrl data TRB "
1417                                         "without IOC set??\n");
1418                         *status = -ESHUTDOWN;
1419                 } else {
1420                         xhci_dbg(xhci, "Successful control transfer!\n");
1421                         *status = 0;
1422                 }
1423                 break;
1424         case COMP_SHORT_TX:
1425                 xhci_warn(xhci, "WARN: short transfer on control ep\n");
1426                 if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
1427                         *status = -EREMOTEIO;
1428                 else
1429                         *status = 0;
1430                 break;
1431         default:
1432                 if (!xhci_requires_manual_halt_cleanup(xhci,
1433                                         ep_ctx, trb_comp_code))
1434                         break;
1435                 xhci_dbg(xhci, "TRB error code %u, "
1436                                 "halted endpoint index = %u\n",
1437                                 trb_comp_code, ep_index);
1438                 /* else fall through */
1439         case COMP_STALL:
1440                 /* Did we transfer part of the data (middle) phase? */
1441                 if (event_trb != ep_ring->dequeue &&
1442                                 event_trb != td->last_trb)
1443                         td->urb->actual_length =
1444                                 td->urb->transfer_buffer_length
1445                                 - TRB_LEN(event->transfer_len);
1446                 else
1447                         td->urb->actual_length = 0;
1448
1449                 xhci_cleanup_halted_endpoint(xhci,
1450                         slot_id, ep_index, 0, td, event_trb);
1451                 return finish_td(xhci, td, event_trb, event, ep, status, true);
1452         }
1453         /*
1454          * Did we transfer any data, despite the errors that might have
1455          * happened?  I.e. did we get past the setup stage?
1456          */
1457         if (event_trb != ep_ring->dequeue) {
1458                 /* The event was for the status stage */
1459                 if (event_trb == td->last_trb) {
1460                         if (td->urb->actual_length != 0) {
1461                                 /* Don't overwrite a previously set error code
1462                                  */
1463                                 if ((*status == -EINPROGRESS || *status == 0) &&
1464                                                 (td->urb->transfer_flags
1465                                                  & URB_SHORT_NOT_OK))
1466                                         /* Did we already see a short data
1467                                          * stage? */
1468                                         *status = -EREMOTEIO;
1469                         } else {
1470                                 td->urb->actual_length =
1471                                         td->urb->transfer_buffer_length;
1472                         }
1473                 } else {
1474                 /* Maybe the event was for the data stage? */
1475                         if (trb_comp_code != COMP_STOP_INVAL) {
1476                                 /* We didn't stop on a link TRB in the middle */
1477                                 td->urb->actual_length =
1478                                         td->urb->transfer_buffer_length -
1479                                         TRB_LEN(event->transfer_len);
1480                                 xhci_dbg(xhci, "Waiting for status "
1481                                                 "stage event\n");
1482                                 return 0;
1483                         }
1484                 }
1485         }
1486
1487         return finish_td(xhci, td, event_trb, event, ep, status, false);
1488 }
1489
1490 /*
1491  * Process isochronous tds, update urb packet status and actual_length.
1492  */
1493 static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
1494         union xhci_trb *event_trb, struct xhci_transfer_event *event,
1495         struct xhci_virt_ep *ep, int *status)
1496 {
1497         struct xhci_ring *ep_ring;
1498         struct urb_priv *urb_priv;
1499         int idx;
1500         int len = 0;
1501         int skip_td = 0;
1502         union xhci_trb *cur_trb;
1503         struct xhci_segment *cur_seg;
1504         u32 trb_comp_code;
1505
1506         ep_ring = xhci_dma_to_transfer_ring(ep, event->buffer);
1507         trb_comp_code = GET_COMP_CODE(event->transfer_len);
1508         urb_priv = td->urb->hcpriv;
1509         idx = urb_priv->td_cnt;
1510
1511         if (ep->skip) {
1512                 /* The transfer is partly done */
1513                 *status = -EXDEV;
1514                 td->urb->iso_frame_desc[idx].status = -EXDEV;
1515         } else {
1516                 /* handle completion code */
1517                 switch (trb_comp_code) {
1518                 case COMP_SUCCESS:
1519                         td->urb->iso_frame_desc[idx].status = 0;
1520                         xhci_dbg(xhci, "Successful isoc transfer!\n");
1521                         break;
1522                 case COMP_SHORT_TX:
1523                         if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
1524                                 td->urb->iso_frame_desc[idx].status =
1525                                          -EREMOTEIO;
1526                         else
1527                                 td->urb->iso_frame_desc[idx].status = 0;
1528                         break;
1529                 case COMP_BW_OVER:
1530                         td->urb->iso_frame_desc[idx].status = -ECOMM;
1531                         skip_td = 1;
1532                         break;
1533                 case COMP_BUFF_OVER:
1534                 case COMP_BABBLE:
1535                         td->urb->iso_frame_desc[idx].status = -EOVERFLOW;
1536                         skip_td = 1;
1537                         break;
1538                 case COMP_STALL:
1539                         td->urb->iso_frame_desc[idx].status = -EPROTO;
1540                         skip_td = 1;
1541                         break;
1542                 case COMP_STOP:
1543                 case COMP_STOP_INVAL:
1544                         break;
1545                 default:
1546                         td->urb->iso_frame_desc[idx].status = -1;
1547                         break;
1548                 }
1549         }
1550
1551         /* calc actual length */
1552         if (ep->skip) {
1553                 td->urb->iso_frame_desc[idx].actual_length = 0;
1554                 return finish_td(xhci, td, event_trb, event, ep, status, true);
1555         }
1556
1557         if (trb_comp_code == COMP_SUCCESS || skip_td == 1) {
1558                 td->urb->iso_frame_desc[idx].actual_length =
1559                         td->urb->iso_frame_desc[idx].length;
1560                 td->urb->actual_length +=
1561                         td->urb->iso_frame_desc[idx].length;
1562         } else {
1563                 for (cur_trb = ep_ring->dequeue,
1564                      cur_seg = ep_ring->deq_seg; cur_trb != event_trb;
1565                      next_trb(xhci, ep_ring, &cur_seg, &cur_trb)) {
1566                         if ((cur_trb->generic.field[3] &
1567                          TRB_TYPE_BITMASK) != TRB_TYPE(TRB_TR_NOOP) &&
1568                             (cur_trb->generic.field[3] &
1569                          TRB_TYPE_BITMASK) != TRB_TYPE(TRB_LINK))
1570                                 len +=
1571                                     TRB_LEN(cur_trb->generic.field[2]);
1572                 }
1573                 len += TRB_LEN(cur_trb->generic.field[2]) -
1574                         TRB_LEN(event->transfer_len);
1575
1576                 if (trb_comp_code != COMP_STOP_INVAL) {
1577                         td->urb->iso_frame_desc[idx].actual_length = len;
1578                         td->urb->actual_length += len;
1579                 }
1580         }
1581
1582         if ((idx == urb_priv->length - 1) && *status == -EINPROGRESS)
1583                 *status = 0;
1584
1585         return finish_td(xhci, td, event_trb, event, ep, status, false);
1586 }
1587
1588 /*
1589  * Process bulk and interrupt tds, update urb status and actual_length.
1590  */
1591 static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td,
1592         union xhci_trb *event_trb, struct xhci_transfer_event *event,
1593         struct xhci_virt_ep *ep, int *status)
1594 {
1595         struct xhci_ring *ep_ring;
1596         union xhci_trb *cur_trb;
1597         struct xhci_segment *cur_seg;
1598         u32 trb_comp_code;
1599
1600         ep_ring = xhci_dma_to_transfer_ring(ep, event->buffer);
1601         trb_comp_code = GET_COMP_CODE(event->transfer_len);
1602
1603         switch (trb_comp_code) {
1604         case COMP_SUCCESS:
1605                 /* Double check that the HW transferred everything. */
1606                 if (event_trb != td->last_trb) {
1607                         xhci_warn(xhci, "WARN Successful completion "
1608                                         "on short TX\n");
1609                         if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
1610                                 *status = -EREMOTEIO;
1611                         else
1612                                 *status = 0;
1613                 } else {
1614                         if (usb_endpoint_xfer_bulk(&td->urb->ep->desc))
1615                                 xhci_dbg(xhci, "Successful bulk "
1616                                                 "transfer!\n");
1617                         else
1618                                 xhci_dbg(xhci, "Successful interrupt "
1619                                                 "transfer!\n");
1620                         *status = 0;
1621                 }
1622                 break;
1623         case COMP_SHORT_TX:
1624                 if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
1625                         *status = -EREMOTEIO;
1626                 else
1627                         *status = 0;
1628                 break;
1629         default:
1630                 /* Others already handled above */
1631                 break;
1632         }
1633         dev_dbg(&td->urb->dev->dev,
1634                         "ep %#x - asked for %d bytes, "
1635                         "%d bytes untransferred\n",
1636                         td->urb->ep->desc.bEndpointAddress,
1637                         td->urb->transfer_buffer_length,
1638                         TRB_LEN(event->transfer_len));
1639         /* Fast path - was this the last TRB in the TD for this URB? */
1640         if (event_trb == td->last_trb) {
1641                 if (TRB_LEN(event->transfer_len) != 0) {
1642                         td->urb->actual_length =
1643                                 td->urb->transfer_buffer_length -
1644                                 TRB_LEN(event->transfer_len);
1645                         if (td->urb->transfer_buffer_length <
1646                                         td->urb->actual_length) {
1647                                 xhci_warn(xhci, "HC gave bad length "
1648                                                 "of %d bytes left\n",
1649                                                 TRB_LEN(event->transfer_len));
1650                                 td->urb->actual_length = 0;
1651                                 if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
1652                                         *status = -EREMOTEIO;
1653                                 else
1654                                         *status = 0;
1655                         }
1656                         /* Don't overwrite a previously set error code */
1657                         if (*status == -EINPROGRESS) {
1658                                 if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
1659                                         *status = -EREMOTEIO;
1660                                 else
1661                                         *status = 0;
1662                         }
1663                 } else {
1664                         td->urb->actual_length =
1665                                 td->urb->transfer_buffer_length;
1666                         /* Ignore a short packet completion if the
1667                          * untransferred length was zero.
1668                          */
1669                         if (*status == -EREMOTEIO)
1670                                 *status = 0;
1671                 }
1672         } else {
1673                 /* Slow path - walk the list, starting from the dequeue
1674                  * pointer, to get the actual length transferred.
1675                  */
1676                 td->urb->actual_length = 0;
1677                 for (cur_trb = ep_ring->dequeue, cur_seg = ep_ring->deq_seg;
1678                                 cur_trb != event_trb;
1679                                 next_trb(xhci, ep_ring, &cur_seg, &cur_trb)) {
1680                         if ((cur_trb->generic.field[3] &
1681                          TRB_TYPE_BITMASK) != TRB_TYPE(TRB_TR_NOOP) &&
1682                             (cur_trb->generic.field[3] &
1683                          TRB_TYPE_BITMASK) != TRB_TYPE(TRB_LINK))
1684                                 td->urb->actual_length +=
1685                                         TRB_LEN(cur_trb->generic.field[2]);
1686                 }
1687                 /* If the ring didn't stop on a Link or No-op TRB, add
1688                  * in the actual bytes transferred from the Normal TRB
1689                  */
1690                 if (trb_comp_code != COMP_STOP_INVAL)
1691                         td->urb->actual_length +=
1692                                 TRB_LEN(cur_trb->generic.field[2]) -
1693                                 TRB_LEN(event->transfer_len);
1694         }
1695
1696         return finish_td(xhci, td, event_trb, event, ep, status, false);
1697 }
1698
1699 /*
1700  * If this function returns an error condition, it means it got a Transfer
1701  * event with a corrupted Slot ID, Endpoint ID, or TRB DMA address.
1702  * At this point, the host controller is probably hosed and should be reset.
1703  */
1704 static int handle_tx_event(struct xhci_hcd *xhci,
1705                 struct xhci_transfer_event *event)
1706 {
1707         struct xhci_virt_device *xdev;
1708         struct xhci_virt_ep *ep;
1709         struct xhci_ring *ep_ring;
1710         unsigned int slot_id;
1711         int ep_index;
1712         struct xhci_td *td = NULL;
1713         dma_addr_t event_dma;
1714         struct xhci_segment *event_seg;
1715         union xhci_trb *event_trb;
1716         struct urb *urb = NULL;
1717         int status = -EINPROGRESS;
1718         struct urb_priv *urb_priv;
1719         struct xhci_ep_ctx *ep_ctx;
1720         u32 trb_comp_code;
1721         int ret = 0;
1722
1723         slot_id = TRB_TO_SLOT_ID(event->flags);
1724         xdev = xhci->devs[slot_id];
1725         if (!xdev) {
1726                 xhci_err(xhci, "ERROR Transfer event pointed to bad slot\n");
1727                 return -ENODEV;
1728         }
1729
1730         /* Endpoint ID is 1 based, our index is zero based */
1731         ep_index = TRB_TO_EP_ID(event->flags) - 1;
1732         xhci_dbg(xhci, "%s - ep index = %d\n", __func__, ep_index);
1733         ep = &xdev->eps[ep_index];
1734         ep_ring = xhci_dma_to_transfer_ring(ep, event->buffer);
1735         ep_ctx = xhci_get_ep_ctx(xhci, xdev->out_ctx, ep_index);
1736         if (!ep_ring ||
1737                 (ep_ctx->ep_info & EP_STATE_MASK) == EP_STATE_DISABLED) {
1738                 xhci_err(xhci, "ERROR Transfer event for disabled endpoint "
1739                                 "or incorrect stream ring\n");
1740                 return -ENODEV;
1741         }
1742
1743         event_dma = event->buffer;
1744         trb_comp_code = GET_COMP_CODE(event->transfer_len);
1745         /* Look for common error cases */
1746         switch (trb_comp_code) {
1747         /* Skip codes that require special handling depending on
1748          * transfer type
1749          */
1750         case COMP_SUCCESS:
1751         case COMP_SHORT_TX:
1752                 break;
1753         case COMP_STOP:
1754                 xhci_dbg(xhci, "Stopped on Transfer TRB\n");
1755                 break;
1756         case COMP_STOP_INVAL:
1757                 xhci_dbg(xhci, "Stopped on No-op or Link TRB\n");
1758                 break;
1759         case COMP_STALL:
1760                 xhci_warn(xhci, "WARN: Stalled endpoint\n");
1761                 ep->ep_state |= EP_HALTED;
1762                 status = -EPIPE;
1763                 break;
1764         case COMP_TRB_ERR:
1765                 xhci_warn(xhci, "WARN: TRB error on endpoint\n");
1766                 status = -EILSEQ;
1767                 break;
1768         case COMP_SPLIT_ERR:
1769         case COMP_TX_ERR:
1770                 xhci_warn(xhci, "WARN: transfer error on endpoint\n");
1771                 status = -EPROTO;
1772                 break;
1773         case COMP_BABBLE:
1774                 xhci_warn(xhci, "WARN: babble error on endpoint\n");
1775                 status = -EOVERFLOW;
1776                 break;
1777         case COMP_DB_ERR:
1778                 xhci_warn(xhci, "WARN: HC couldn't access mem fast enough\n");
1779                 status = -ENOSR;
1780                 break;
1781         case COMP_BW_OVER:
1782                 xhci_warn(xhci, "WARN: bandwidth overrun event on endpoint\n");
1783                 break;
1784         case COMP_BUFF_OVER:
1785                 xhci_warn(xhci, "WARN: buffer overrun event on endpoint\n");
1786                 break;
1787         case COMP_UNDERRUN:
1788                 /*
1789                  * When the Isoch ring is empty, the xHC will generate
1790                  * a Ring Overrun Event for IN Isoch endpoint or Ring
1791                  * Underrun Event for OUT Isoch endpoint.
1792                  */
1793                 xhci_dbg(xhci, "underrun event on endpoint\n");
1794                 if (!list_empty(&ep_ring->td_list))
1795                         xhci_dbg(xhci, "Underrun Event for slot %d ep %d "
1796                                         "still with TDs queued?\n",
1797                                 TRB_TO_SLOT_ID(event->flags), ep_index);
1798                 goto cleanup;
1799         case COMP_OVERRUN:
1800                 xhci_dbg(xhci, "overrun event on endpoint\n");
1801                 if (!list_empty(&ep_ring->td_list))
1802                         xhci_dbg(xhci, "Overrun Event for slot %d ep %d "
1803                                         "still with TDs queued?\n",
1804                                 TRB_TO_SLOT_ID(event->flags), ep_index);
1805                 goto cleanup;
1806         case COMP_MISSED_INT:
1807                 /*
1808                  * When encounter missed service error, one or more isoc tds
1809                  * may be missed by xHC.
1810                  * Set skip flag of the ep_ring; Complete the missed tds as
1811                  * short transfer when process the ep_ring next time.
1812                  */
1813                 ep->skip = true;
1814                 xhci_dbg(xhci, "Miss service interval error, set skip flag\n");
1815                 goto cleanup;
1816         default:
1817                 if (xhci_is_vendor_info_code(xhci, trb_comp_code)) {
1818                         status = 0;
1819                         break;
1820                 }
1821                 xhci_warn(xhci, "ERROR Unknown event condition, HC probably "
1822                                 "busted\n");
1823                 goto cleanup;
1824         }
1825
1826         do {
1827                 /* This TRB should be in the TD at the head of this ring's
1828                  * TD list.
1829                  */
1830                 if (list_empty(&ep_ring->td_list)) {
1831                         xhci_warn(xhci, "WARN Event TRB for slot %d ep %d "
1832                                         "with no TDs queued?\n",
1833                                   TRB_TO_SLOT_ID(event->flags), ep_index);
1834                         xhci_dbg(xhci, "Event TRB with TRB type ID %u\n",
1835                           (unsigned int) (event->flags & TRB_TYPE_BITMASK)>>10);
1836                         xhci_print_trb_offsets(xhci, (union xhci_trb *) event);
1837                         if (ep->skip) {
1838                                 ep->skip = false;
1839                                 xhci_dbg(xhci, "td_list is empty while skip "
1840                                                 "flag set. Clear skip flag.\n");
1841                         }
1842                         ret = 0;
1843                         goto cleanup;
1844                 }
1845
1846                 td = list_entry(ep_ring->td_list.next, struct xhci_td, td_list);
1847                 /* Is this a TRB in the currently executing TD? */
1848                 event_seg = trb_in_td(ep_ring->deq_seg, ep_ring->dequeue,
1849                                 td->last_trb, event_dma);
1850                 if (event_seg && ep->skip) {
1851                         xhci_dbg(xhci, "Found td. Clear skip flag.\n");
1852                         ep->skip = false;
1853                 }
1854                 if (!event_seg &&
1855                    (!ep->skip || !usb_endpoint_xfer_isoc(&td->urb->ep->desc))) {
1856                         /* HC is busted, give up! */
1857                         xhci_err(xhci, "ERROR Transfer event TRB DMA ptr not "
1858                                         "part of current TD\n");
1859                         return -ESHUTDOWN;
1860                 }
1861
1862                 if (event_seg) {
1863                         event_trb = &event_seg->trbs[(event_dma -
1864                                          event_seg->dma) / sizeof(*event_trb)];
1865                         /*
1866                          * No-op TRB should not trigger interrupts.
1867                          * If event_trb is a no-op TRB, it means the
1868                          * corresponding TD has been cancelled. Just ignore
1869                          * the TD.
1870                          */
1871                         if ((event_trb->generic.field[3] & TRB_TYPE_BITMASK)
1872                                          == TRB_TYPE(TRB_TR_NOOP)) {
1873                                 xhci_dbg(xhci, "event_trb is a no-op TRB. "
1874                                                 "Skip it\n");
1875                                 goto cleanup;
1876                         }
1877                 }
1878
1879                 /* Now update the urb's actual_length and give back to
1880                  * the core
1881                  */
1882                 if (usb_endpoint_xfer_control(&td->urb->ep->desc))
1883                         ret = process_ctrl_td(xhci, td, event_trb, event, ep,
1884                                                  &status);
1885                 else if (usb_endpoint_xfer_isoc(&td->urb->ep->desc))
1886                         ret = process_isoc_td(xhci, td, event_trb, event, ep,
1887                                                  &status);
1888                 else
1889                         ret = process_bulk_intr_td(xhci, td, event_trb, event,
1890                                                  ep, &status);
1891
1892 cleanup:
1893                 /*
1894                  * Do not update event ring dequeue pointer if ep->skip is set.
1895                  * Will roll back to continue process missed tds.
1896                  */
1897                 if (trb_comp_code == COMP_MISSED_INT || !ep->skip) {
1898                         inc_deq(xhci, xhci->event_ring, true);
1899                 }
1900
1901                 if (ret) {
1902                         urb = td->urb;
1903                         urb_priv = urb->hcpriv;
1904                         /* Leave the TD around for the reset endpoint function
1905                          * to use(but only if it's not a control endpoint,
1906                          * since we already queued the Set TR dequeue pointer
1907                          * command for stalled control endpoints).
1908                          */
1909                         if (usb_endpoint_xfer_control(&urb->ep->desc) ||
1910                                 (trb_comp_code != COMP_STALL &&
1911                                         trb_comp_code != COMP_BABBLE))
1912                                 xhci_urb_free_priv(xhci, urb_priv);
1913
1914                         usb_hcd_unlink_urb_from_ep(xhci_to_hcd(xhci), urb);
1915                         xhci_dbg(xhci, "Giveback URB %p, len = %d, "
1916                                         "status = %d\n",
1917                                         urb, urb->actual_length, status);
1918                         spin_unlock(&xhci->lock);
1919                         usb_hcd_giveback_urb(xhci_to_hcd(xhci), urb, status);
1920                         spin_lock(&xhci->lock);
1921                 }
1922
1923         /*
1924          * If ep->skip is set, it means there are missed tds on the
1925          * endpoint ring need to take care of.
1926          * Process them as short transfer until reach the td pointed by
1927          * the event.
1928          */
1929         } while (ep->skip && trb_comp_code != COMP_MISSED_INT);
1930
1931         return 0;
1932 }
1933
1934 /*
1935  * This function handles all OS-owned events on the event ring.  It may drop
1936  * xhci->lock between event processing (e.g. to pass up port status changes).
1937  */
1938 static void xhci_handle_event(struct xhci_hcd *xhci)
1939 {
1940         union xhci_trb *event;
1941         int update_ptrs = 1;
1942         int ret;
1943
1944         xhci_dbg(xhci, "In %s\n", __func__);
1945         if (!xhci->event_ring || !xhci->event_ring->dequeue) {
1946                 xhci->error_bitmask |= 1 << 1;
1947                 return;
1948         }
1949
1950         event = xhci->event_ring->dequeue;
1951         /* Does the HC or OS own the TRB? */
1952         if ((event->event_cmd.flags & TRB_CYCLE) !=
1953                         xhci->event_ring->cycle_state) {
1954                 xhci->error_bitmask |= 1 << 2;
1955                 return;
1956         }
1957         xhci_dbg(xhci, "%s - OS owns TRB\n", __func__);
1958
1959         /* FIXME: Handle more event types. */
1960         switch ((event->event_cmd.flags & TRB_TYPE_BITMASK)) {
1961         case TRB_TYPE(TRB_COMPLETION):
1962                 xhci_dbg(xhci, "%s - calling handle_cmd_completion\n", __func__);
1963                 handle_cmd_completion(xhci, &event->event_cmd);
1964                 xhci_dbg(xhci, "%s - returned from handle_cmd_completion\n", __func__);
1965                 break;
1966         case TRB_TYPE(TRB_PORT_STATUS):
1967                 xhci_dbg(xhci, "%s - calling handle_port_status\n", __func__);
1968                 handle_port_status(xhci, event);
1969                 xhci_dbg(xhci, "%s - returned from handle_port_status\n", __func__);
1970                 update_ptrs = 0;
1971                 break;
1972         case TRB_TYPE(TRB_TRANSFER):
1973                 xhci_dbg(xhci, "%s - calling handle_tx_event\n", __func__);
1974                 ret = handle_tx_event(xhci, &event->trans_event);
1975                 xhci_dbg(xhci, "%s - returned from handle_tx_event\n", __func__);
1976                 if (ret < 0)
1977                         xhci->error_bitmask |= 1 << 9;
1978                 else
1979                         update_ptrs = 0;
1980                 break;
1981         default:
1982                 if ((event->event_cmd.flags & TRB_TYPE_BITMASK) >= TRB_TYPE(48))
1983                         handle_vendor_event(xhci, event);
1984                 else
1985                         xhci->error_bitmask |= 1 << 3;
1986         }
1987         /* Any of the above functions may drop and re-acquire the lock, so check
1988          * to make sure a watchdog timer didn't mark the host as non-responsive.
1989          */
1990         if (xhci->xhc_state & XHCI_STATE_DYING) {
1991                 xhci_dbg(xhci, "xHCI host dying, returning from "
1992                                 "event handler.\n");
1993                 return;
1994         }
1995
1996         if (update_ptrs)
1997                 /* Update SW event ring dequeue pointer */
1998                 inc_deq(xhci, xhci->event_ring, true);
1999
2000         /* Are there more items on the event ring? */
2001         xhci_handle_event(xhci);
2002 }
2003
2004 /*
2005  * xHCI spec says we can get an interrupt, and if the HC has an error condition,
2006  * we might get bad data out of the event ring.  Section 4.10.2.7 has a list of
2007  * indicators of an event TRB error, but we check the status *first* to be safe.
2008  */
2009 irqreturn_t xhci_irq(struct usb_hcd *hcd)
2010 {
2011         struct xhci_hcd *xhci = hcd_to_xhci(hcd);
2012         u32 status;
2013         union xhci_trb *trb;
2014         u64 temp_64;
2015         union xhci_trb *event_ring_deq;
2016         dma_addr_t deq;
2017
2018         spin_lock(&xhci->lock);
2019         trb = xhci->event_ring->dequeue;
2020         /* Check if the xHC generated the interrupt, or the irq is shared */
2021         status = xhci_readl(xhci, &xhci->op_regs->status);
2022         if (status == 0xffffffff)
2023                 goto hw_died;
2024
2025         if (!(status & STS_EINT)) {
2026                 spin_unlock(&xhci->lock);
2027                 xhci_warn(xhci, "Spurious interrupt.\n");
2028                 return IRQ_NONE;
2029         }
2030         xhci_dbg(xhci, "op reg status = %08x\n", status);
2031         xhci_dbg(xhci, "Event ring dequeue ptr:\n");
2032         xhci_dbg(xhci, "@%llx %08x %08x %08x %08x\n",
2033                         (unsigned long long)
2034                         xhci_trb_virt_to_dma(xhci->event_ring->deq_seg, trb),
2035                         lower_32_bits(trb->link.segment_ptr),
2036                         upper_32_bits(trb->link.segment_ptr),
2037                         (unsigned int) trb->link.intr_target,
2038                         (unsigned int) trb->link.control);
2039
2040         if (status & STS_FATAL) {
2041                 xhci_warn(xhci, "WARNING: Host System Error\n");
2042                 xhci_halt(xhci);
2043 hw_died:
2044                 xhci_to_hcd(xhci)->state = HC_STATE_HALT;
2045                 spin_unlock(&xhci->lock);
2046                 return -ESHUTDOWN;
2047         }
2048
2049         /*
2050          * Clear the op reg interrupt status first,
2051          * so we can receive interrupts from other MSI-X interrupters.
2052          * Write 1 to clear the interrupt status.
2053          */
2054         status |= STS_EINT;
2055         xhci_writel(xhci, status, &xhci->op_regs->status);
2056         /* FIXME when MSI-X is supported and there are multiple vectors */
2057         /* Clear the MSI-X event interrupt status */
2058
2059         if (hcd->irq != -1) {
2060                 u32 irq_pending;
2061                 /* Acknowledge the PCI interrupt */
2062                 irq_pending = xhci_readl(xhci, &xhci->ir_set->irq_pending);
2063                 irq_pending |= 0x3;
2064                 xhci_writel(xhci, irq_pending, &xhci->ir_set->irq_pending);
2065         }
2066
2067         if (xhci->xhc_state & XHCI_STATE_DYING) {
2068                 xhci_dbg(xhci, "xHCI dying, ignoring interrupt. "
2069                                 "Shouldn't IRQs be disabled?\n");
2070                 /* Clear the event handler busy flag (RW1C);
2071                  * the event ring should be empty.
2072                  */
2073                 temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
2074                 xhci_write_64(xhci, temp_64 | ERST_EHB,
2075                                 &xhci->ir_set->erst_dequeue);
2076                 spin_unlock(&xhci->lock);
2077
2078                 return IRQ_HANDLED;
2079         }
2080
2081         event_ring_deq = xhci->event_ring->dequeue;
2082         /* FIXME this should be a delayed service routine
2083          * that clears the EHB.
2084          */
2085         xhci_handle_event(xhci);
2086
2087         temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
2088         /* If necessary, update the HW's version of the event ring deq ptr. */
2089         if (event_ring_deq != xhci->event_ring->dequeue) {
2090                 deq = xhci_trb_virt_to_dma(xhci->event_ring->deq_seg,
2091                                 xhci->event_ring->dequeue);
2092                 if (deq == 0)
2093                         xhci_warn(xhci, "WARN something wrong with SW event "
2094                                         "ring dequeue ptr.\n");
2095                 /* Update HC event ring dequeue pointer */
2096                 temp_64 &= ERST_PTR_MASK;
2097                 temp_64 |= ((u64) deq & (u64) ~ERST_PTR_MASK);
2098         }
2099
2100         /* Clear the event handler busy flag (RW1C); event ring is empty. */
2101         temp_64 |= ERST_EHB;
2102         xhci_write_64(xhci, temp_64, &xhci->ir_set->erst_dequeue);
2103
2104         spin_unlock(&xhci->lock);
2105
2106         return IRQ_HANDLED;
2107 }
2108
2109 irqreturn_t xhci_msi_irq(int irq, struct usb_hcd *hcd)
2110 {
2111         irqreturn_t ret;
2112
2113         set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
2114
2115         ret = xhci_irq(hcd);
2116
2117         return ret;
2118 }
2119
2120 /****           Endpoint Ring Operations        ****/
2121
2122 /*
2123  * Generic function for queueing a TRB on a ring.
2124  * The caller must have checked to make sure there's room on the ring.
2125  *
2126  * @more_trbs_coming:   Will you enqueue more TRBs before calling
2127  *                      prepare_transfer()?
2128  */
2129 static void queue_trb(struct xhci_hcd *xhci, struct xhci_ring *ring,
2130                 bool consumer, bool more_trbs_coming,
2131                 u32 field1, u32 field2, u32 field3, u32 field4)
2132 {
2133         struct xhci_generic_trb *trb;
2134
2135         trb = &ring->enqueue->generic;
2136         trb->field[0] = field1;
2137         trb->field[1] = field2;
2138         trb->field[2] = field3;
2139         trb->field[3] = field4;
2140         inc_enq(xhci, ring, consumer, more_trbs_coming);
2141 }
2142
2143 /*
2144  * Does various checks on the endpoint ring, and makes it ready to queue num_trbs.
2145  * FIXME allocate segments if the ring is full.
2146  */
2147 static int prepare_ring(struct xhci_hcd *xhci, struct xhci_ring *ep_ring,
2148                 u32 ep_state, unsigned int num_trbs, gfp_t mem_flags)
2149 {
2150         /* Make sure the endpoint has been added to xHC schedule */
2151         xhci_dbg(xhci, "Endpoint state = 0x%x\n", ep_state);
2152         switch (ep_state) {
2153         case EP_STATE_DISABLED:
2154                 /*
2155                  * USB core changed config/interfaces without notifying us,
2156                  * or hardware is reporting the wrong state.
2157                  */
2158                 xhci_warn(xhci, "WARN urb submitted to disabled ep\n");
2159                 return -ENOENT;
2160         case EP_STATE_ERROR:
2161                 xhci_warn(xhci, "WARN waiting for error on ep to be cleared\n");
2162                 /* FIXME event handling code for error needs to clear it */
2163                 /* XXX not sure if this should be -ENOENT or not */
2164                 return -EINVAL;
2165         case EP_STATE_HALTED:
2166                 xhci_dbg(xhci, "WARN halted endpoint, queueing URB anyway.\n");
2167         case EP_STATE_STOPPED:
2168         case EP_STATE_RUNNING:
2169                 break;
2170         default:
2171                 xhci_err(xhci, "ERROR unknown endpoint state for ep\n");
2172                 /*
2173                  * FIXME issue Configure Endpoint command to try to get the HC
2174                  * back into a known state.
2175                  */
2176                 return -EINVAL;
2177         }
2178         if (!room_on_ring(xhci, ep_ring, num_trbs)) {
2179                 /* FIXME allocate more room */
2180                 xhci_err(xhci, "ERROR no room on ep ring\n");
2181                 return -ENOMEM;
2182         }
2183
2184         if (enqueue_is_link_trb(ep_ring)) {
2185                 struct xhci_ring *ring = ep_ring;
2186                 union xhci_trb *next;
2187
2188                 xhci_dbg(xhci, "prepare_ring: pointing to link trb\n");
2189                 next = ring->enqueue;
2190
2191                 while (last_trb(xhci, ring, ring->enq_seg, next)) {
2192
2193                         /* If we're not dealing with 0.95 hardware,
2194                          * clear the chain bit.
2195                          */
2196                         if (!xhci_link_trb_quirk(xhci))
2197                                 next->link.control &= ~TRB_CHAIN;
2198                         else
2199                                 next->link.control |= TRB_CHAIN;
2200
2201                         wmb();
2202                         next->link.control ^= (u32) TRB_CYCLE;
2203
2204                         /* Toggle the cycle bit after the last ring segment. */
2205                         if (last_trb_on_last_seg(xhci, ring, ring->enq_seg, next)) {
2206                                 ring->cycle_state = (ring->cycle_state ? 0 : 1);
2207                                 if (!in_interrupt()) {
2208                                         xhci_dbg(xhci, "queue_trb: Toggle cycle "
2209                                                 "state for ring %p = %i\n",
2210                                                 ring, (unsigned int)ring->cycle_state);
2211                                 }
2212                         }
2213                         ring->enq_seg = ring->enq_seg->next;
2214                         ring->enqueue = ring->enq_seg->trbs;
2215                         next = ring->enqueue;
2216                 }
2217         }
2218
2219         return 0;
2220 }
2221
2222 static int prepare_transfer(struct xhci_hcd *xhci,
2223                 struct xhci_virt_device *xdev,
2224                 unsigned int ep_index,
2225                 unsigned int stream_id,
2226                 unsigned int num_trbs,
2227                 struct urb *urb,
2228                 unsigned int td_index,
2229                 gfp_t mem_flags)
2230 {
2231         int ret;
2232         struct urb_priv *urb_priv;
2233         struct xhci_td  *td;
2234         struct xhci_ring *ep_ring;
2235         struct xhci_ep_ctx *ep_ctx = xhci_get_ep_ctx(xhci, xdev->out_ctx, ep_index);
2236
2237         ep_ring = xhci_stream_id_to_ring(xdev, ep_index, stream_id);
2238         if (!ep_ring) {
2239                 xhci_dbg(xhci, "Can't prepare ring for bad stream ID %u\n",
2240                                 stream_id);
2241                 return -EINVAL;
2242         }
2243
2244         ret = prepare_ring(xhci, ep_ring,
2245                         ep_ctx->ep_info & EP_STATE_MASK,
2246                         num_trbs, mem_flags);
2247         if (ret)
2248                 return ret;
2249
2250         urb_priv = urb->hcpriv;
2251         td = urb_priv->td[td_index];
2252
2253         INIT_LIST_HEAD(&td->td_list);
2254         INIT_LIST_HEAD(&td->cancelled_td_list);
2255
2256         if (td_index == 0) {
2257                 ret = usb_hcd_link_urb_to_ep(xhci_to_hcd(xhci), urb);
2258                 if (unlikely(ret)) {
2259                         xhci_urb_free_priv(xhci, urb_priv);
2260                         urb->hcpriv = NULL;
2261                         return ret;
2262                 }
2263         }
2264
2265         td->urb = urb;
2266         /* Add this TD to the tail of the endpoint ring's TD list */
2267         list_add_tail(&td->td_list, &ep_ring->td_list);
2268         td->start_seg = ep_ring->enq_seg;
2269         td->first_trb = ep_ring->enqueue;
2270
2271         urb_priv->td[td_index] = td;
2272
2273         return 0;
2274 }
2275
2276 static unsigned int count_sg_trbs_needed(struct xhci_hcd *xhci, struct urb *urb)
2277 {
2278         int num_sgs, num_trbs, running_total, temp, i;
2279         struct scatterlist *sg;
2280
2281         sg = NULL;
2282         num_sgs = urb->num_sgs;
2283         temp = urb->transfer_buffer_length;
2284
2285         xhci_dbg(xhci, "count sg list trbs: \n");
2286         num_trbs = 0;
2287         for_each_sg(urb->sg, sg, num_sgs, i) {
2288                 unsigned int previous_total_trbs = num_trbs;
2289                 unsigned int len = sg_dma_len(sg);
2290
2291                 /* Scatter gather list entries may cross 64KB boundaries */
2292                 running_total = TRB_MAX_BUFF_SIZE -
2293                         (sg_dma_address(sg) & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
2294                 if (running_total != 0)
2295                         num_trbs++;
2296
2297                 /* How many more 64KB chunks to transfer, how many more TRBs? */
2298                 while (running_total < sg_dma_len(sg)) {
2299                         num_trbs++;
2300                         running_total += TRB_MAX_BUFF_SIZE;
2301                 }
2302                 xhci_dbg(xhci, " sg #%d: dma = %#llx, len = %#x (%d), num_trbs = %d\n",
2303                                 i, (unsigned long long)sg_dma_address(sg),
2304                                 len, len, num_trbs - previous_total_trbs);
2305
2306                 len = min_t(int, len, temp);
2307                 temp -= len;
2308                 if (temp == 0)
2309                         break;
2310         }
2311         xhci_dbg(xhci, "\n");
2312         if (!in_interrupt())
2313                 dev_dbg(&urb->dev->dev, "ep %#x - urb len = %d, sglist used, num_trbs = %d\n",
2314                                 urb->ep->desc.bEndpointAddress,
2315                                 urb->transfer_buffer_length,
2316                                 num_trbs);
2317         return num_trbs;
2318 }
2319
2320 static void check_trb_math(struct urb *urb, int num_trbs, int running_total)
2321 {
2322         if (num_trbs != 0)
2323                 dev_dbg(&urb->dev->dev, "%s - ep %#x - Miscalculated number of "
2324                                 "TRBs, %d left\n", __func__,
2325                                 urb->ep->desc.bEndpointAddress, num_trbs);
2326         if (running_total != urb->transfer_buffer_length)
2327                 dev_dbg(&urb->dev->dev, "%s - ep %#x - Miscalculated tx length, "
2328                                 "queued %#x (%d), asked for %#x (%d)\n",
2329                                 __func__,
2330                                 urb->ep->desc.bEndpointAddress,
2331                                 running_total, running_total,
2332                                 urb->transfer_buffer_length,
2333                                 urb->transfer_buffer_length);
2334 }
2335
2336 static void giveback_first_trb(struct xhci_hcd *xhci, int slot_id,
2337                 unsigned int ep_index, unsigned int stream_id, int start_cycle,
2338                 struct xhci_generic_trb *start_trb, struct xhci_td *td)
2339 {
2340         /*
2341          * Pass all the TRBs to the hardware at once and make sure this write
2342          * isn't reordered.
2343          */
2344         wmb();
2345         start_trb->field[3] |= start_cycle;
2346         ring_ep_doorbell(xhci, slot_id, ep_index, stream_id);
2347 }
2348
2349 /*
2350  * xHCI uses normal TRBs for both bulk and interrupt.  When the interrupt
2351  * endpoint is to be serviced, the xHC will consume (at most) one TD.  A TD
2352  * (comprised of sg list entries) can take several service intervals to
2353  * transmit.
2354  */
2355 int xhci_queue_intr_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
2356                 struct urb *urb, int slot_id, unsigned int ep_index)
2357 {
2358         struct xhci_ep_ctx *ep_ctx = xhci_get_ep_ctx(xhci,
2359                         xhci->devs[slot_id]->out_ctx, ep_index);
2360         int xhci_interval;
2361         int ep_interval;
2362
2363         xhci_interval = EP_INTERVAL_TO_UFRAMES(ep_ctx->ep_info);
2364         ep_interval = urb->interval;
2365         /* Convert to microframes */
2366         if (urb->dev->speed == USB_SPEED_LOW ||
2367                         urb->dev->speed == USB_SPEED_FULL)
2368                 ep_interval *= 8;
2369         /* FIXME change this to a warning and a suggestion to use the new API
2370          * to set the polling interval (once the API is added).
2371          */
2372         if (xhci_interval != ep_interval) {
2373                 if (!printk_ratelimit())
2374                         dev_dbg(&urb->dev->dev, "Driver uses different interval"
2375                                         " (%d microframe%s) than xHCI "
2376                                         "(%d microframe%s)\n",
2377                                         ep_interval,
2378                                         ep_interval == 1 ? "" : "s",
2379                                         xhci_interval,
2380                                         xhci_interval == 1 ? "" : "s");
2381                 urb->interval = xhci_interval;
2382                 /* Convert back to frames for LS/FS devices */
2383                 if (urb->dev->speed == USB_SPEED_LOW ||
2384                                 urb->dev->speed == USB_SPEED_FULL)
2385                         urb->interval /= 8;
2386         }
2387         return xhci_queue_bulk_tx(xhci, GFP_ATOMIC, urb, slot_id, ep_index);
2388 }
2389
2390 /*
2391  * The TD size is the number of bytes remaining in the TD (including this TRB),
2392  * right shifted by 10.
2393  * It must fit in bits 21:17, so it can't be bigger than 31.
2394  */
2395 static u32 xhci_td_remainder(unsigned int remainder)
2396 {
2397         u32 max = (1 << (21 - 17 + 1)) - 1;
2398
2399         if ((remainder >> 10) >= max)
2400                 return max << 17;
2401         else
2402                 return (remainder >> 10) << 17;
2403 }
2404
2405 static int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
2406                 struct urb *urb, int slot_id, unsigned int ep_index)
2407 {
2408         struct xhci_ring *ep_ring;
2409         unsigned int num_trbs;
2410         struct urb_priv *urb_priv;
2411         struct xhci_td *td;
2412         struct scatterlist *sg;
2413         int num_sgs;
2414         int trb_buff_len, this_sg_len, running_total;
2415         bool first_trb;
2416         u64 addr;
2417         bool more_trbs_coming;
2418
2419         struct xhci_generic_trb *start_trb;
2420         int start_cycle;
2421
2422         ep_ring = xhci_urb_to_transfer_ring(xhci, urb);
2423         if (!ep_ring)
2424                 return -EINVAL;
2425
2426         num_trbs = count_sg_trbs_needed(xhci, urb);
2427         num_sgs = urb->num_sgs;
2428
2429         trb_buff_len = prepare_transfer(xhci, xhci->devs[slot_id],
2430                         ep_index, urb->stream_id,
2431                         num_trbs, urb, 0, mem_flags);
2432         if (trb_buff_len < 0)
2433                 return trb_buff_len;
2434
2435         urb_priv = urb->hcpriv;
2436         td = urb_priv->td[0];
2437
2438         /*
2439          * Don't give the first TRB to the hardware (by toggling the cycle bit)
2440          * until we've finished creating all the other TRBs.  The ring's cycle
2441          * state may change as we enqueue the other TRBs, so save it too.
2442          */
2443         start_trb = &ep_ring->enqueue->generic;
2444         start_cycle = ep_ring->cycle_state;
2445
2446         running_total = 0;
2447         /*
2448          * How much data is in the first TRB?
2449          *
2450          * There are three forces at work for TRB buffer pointers and lengths:
2451          * 1. We don't want to walk off the end of this sg-list entry buffer.
2452          * 2. The transfer length that the driver requested may be smaller than
2453          *    the amount of memory allocated for this scatter-gather list.
2454          * 3. TRBs buffers can't cross 64KB boundaries.
2455          */
2456         sg = urb->sg;
2457         addr = (u64) sg_dma_address(sg);
2458         this_sg_len = sg_dma_len(sg);
2459         trb_buff_len = TRB_MAX_BUFF_SIZE -
2460                 (addr & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
2461         trb_buff_len = min_t(int, trb_buff_len, this_sg_len);
2462         if (trb_buff_len > urb->transfer_buffer_length)
2463                 trb_buff_len = urb->transfer_buffer_length;
2464         xhci_dbg(xhci, "First length to xfer from 1st sglist entry = %u\n",
2465                         trb_buff_len);
2466
2467         first_trb = true;
2468         /* Queue the first TRB, even if it's zero-length */
2469         do {
2470                 u32 field = 0;
2471                 u32 length_field = 0;
2472                 u32 remainder = 0;
2473
2474                 /* Don't change the cycle bit of the first TRB until later */
2475                 if (first_trb)
2476                         first_trb = false;
2477                 else
2478                         field |= ep_ring->cycle_state;
2479
2480                 /* Chain all the TRBs together; clear the chain bit in the last
2481                  * TRB to indicate it's the last TRB in the chain.
2482                  */
2483                 if (num_trbs > 1) {
2484                         field |= TRB_CHAIN;
2485                 } else {
2486                         /* FIXME - add check for ZERO_PACKET flag before this */
2487                         td->last_trb = ep_ring->enqueue;
2488                         field |= TRB_IOC;
2489                 }
2490                 xhci_dbg(xhci, " sg entry: dma = %#x, len = %#x (%d), "
2491                                 "64KB boundary at %#x, end dma = %#x\n",
2492                                 (unsigned int) addr, trb_buff_len, trb_buff_len,
2493                                 (unsigned int) (addr + TRB_MAX_BUFF_SIZE) & ~(TRB_MAX_BUFF_SIZE - 1),
2494                                 (unsigned int) addr + trb_buff_len);
2495                 if (TRB_MAX_BUFF_SIZE -
2496                                 (addr & ((1 << TRB_MAX_BUFF_SHIFT) - 1)) < trb_buff_len) {
2497                         xhci_warn(xhci, "WARN: sg dma xfer crosses 64KB boundaries!\n");
2498                         xhci_dbg(xhci, "Next boundary at %#x, end dma = %#x\n",
2499                                         (unsigned int) (addr + TRB_MAX_BUFF_SIZE) & ~(TRB_MAX_BUFF_SIZE - 1),
2500                                         (unsigned int) addr + trb_buff_len);
2501                 }
2502                 remainder = xhci_td_remainder(urb->transfer_buffer_length -
2503                                 running_total) ;
2504                 length_field = TRB_LEN(trb_buff_len) |
2505                         remainder |
2506                         TRB_INTR_TARGET(0);
2507                 if (num_trbs > 1)
2508                         more_trbs_coming = true;
2509                 else
2510                         more_trbs_coming = false;
2511                 queue_trb(xhci, ep_ring, false, more_trbs_coming,
2512                                 lower_32_bits(addr),
2513                                 upper_32_bits(addr),
2514                                 length_field,
2515                                 /* We always want to know if the TRB was short,
2516                                  * or we won't get an event when it completes.
2517                                  * (Unless we use event data TRBs, which are a
2518                                  * waste of space and HC resources.)
2519                                  */
2520                                 field | TRB_ISP | TRB_TYPE(TRB_NORMAL));
2521                 --num_trbs;
2522                 running_total += trb_buff_len;
2523
2524                 /* Calculate length for next transfer --
2525                  * Are we done queueing all the TRBs for this sg entry?
2526                  */
2527                 this_sg_len -= trb_buff_len;
2528                 if (this_sg_len == 0) {
2529                         --num_sgs;
2530                         if (num_sgs == 0)
2531                                 break;
2532                         sg = sg_next(sg);
2533                         addr = (u64) sg_dma_address(sg);
2534                         this_sg_len = sg_dma_len(sg);
2535                 } else {
2536                         addr += trb_buff_len;
2537                 }
2538
2539                 trb_buff_len = TRB_MAX_BUFF_SIZE -
2540                         (addr & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
2541                 trb_buff_len = min_t(int, trb_buff_len, this_sg_len);
2542                 if (running_total + trb_buff_len > urb->transfer_buffer_length)
2543                         trb_buff_len =
2544                                 urb->transfer_buffer_length - running_total;
2545         } while (running_total < urb->transfer_buffer_length);
2546
2547         check_trb_math(urb, num_trbs, running_total);
2548         giveback_first_trb(xhci, slot_id, ep_index, urb->stream_id,
2549                         start_cycle, start_trb, td);
2550         return 0;
2551 }
2552
2553 /* This is very similar to what ehci-q.c qtd_fill() does */
2554 int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
2555                 struct urb *urb, int slot_id, unsigned int ep_index)
2556 {
2557         struct xhci_ring *ep_ring;
2558         struct urb_priv *urb_priv;
2559         struct xhci_td *td;
2560         int num_trbs;
2561         struct xhci_generic_trb *start_trb;
2562         bool first_trb;
2563         bool more_trbs_coming;
2564         int start_cycle;
2565         u32 field, length_field;
2566
2567         int running_total, trb_buff_len, ret;
2568         u64 addr;
2569
2570         if (urb->num_sgs)
2571                 return queue_bulk_sg_tx(xhci, mem_flags, urb, slot_id, ep_index);
2572
2573         ep_ring = xhci_urb_to_transfer_ring(xhci, urb);
2574         if (!ep_ring)
2575                 return -EINVAL;
2576
2577         num_trbs = 0;
2578         /* How much data is (potentially) left before the 64KB boundary? */
2579         running_total = TRB_MAX_BUFF_SIZE -
2580                 (urb->transfer_dma & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
2581
2582         /* If there's some data on this 64KB chunk, or we have to send a
2583          * zero-length transfer, we need at least one TRB
2584          */
2585         if (running_total != 0 || urb->transfer_buffer_length == 0)
2586                 num_trbs++;
2587         /* How many more 64KB chunks to transfer, how many more TRBs? */
2588         while (running_total < urb->transfer_buffer_length) {
2589                 num_trbs++;
2590                 running_total += TRB_MAX_BUFF_SIZE;
2591         }
2592         /* FIXME: this doesn't deal with URB_ZERO_PACKET - need one more */
2593
2594         if (!in_interrupt())
2595                 dev_dbg(&urb->dev->dev, "ep %#x - urb len = %#x (%d), addr = %#llx, num_trbs = %d\n",
2596                                 urb->ep->desc.bEndpointAddress,
2597                                 urb->transfer_buffer_length,
2598                                 urb->transfer_buffer_length,
2599                                 (unsigned long long)urb->transfer_dma,
2600                                 num_trbs);
2601
2602         ret = prepare_transfer(xhci, xhci->devs[slot_id],
2603                         ep_index, urb->stream_id,
2604                         num_trbs, urb, 0, mem_flags);
2605         if (ret < 0)
2606                 return ret;
2607
2608         urb_priv = urb->hcpriv;
2609         td = urb_priv->td[0];
2610
2611         /*
2612          * Don't give the first TRB to the hardware (by toggling the cycle bit)
2613          * until we've finished creating all the other TRBs.  The ring's cycle
2614          * state may change as we enqueue the other TRBs, so save it too.
2615          */
2616         start_trb = &ep_ring->enqueue->generic;
2617         start_cycle = ep_ring->cycle_state;
2618
2619         running_total = 0;
2620         /* How much data is in the first TRB? */
2621         addr = (u64) urb->transfer_dma;
2622         trb_buff_len = TRB_MAX_BUFF_SIZE -
2623                 (urb->transfer_dma & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
2624         if (urb->transfer_buffer_length < trb_buff_len)
2625                 trb_buff_len = urb->transfer_buffer_length;
2626
2627         first_trb = true;
2628
2629         /* Queue the first TRB, even if it's zero-length */
2630         do {
2631                 u32 remainder = 0;
2632                 field = 0;
2633
2634                 /* Don't change the cycle bit of the first TRB until later */
2635                 if (first_trb)
2636                         first_trb = false;
2637                 else
2638                         field |= ep_ring->cycle_state;
2639
2640                 /* Chain all the TRBs together; clear the chain bit in the last
2641                  * TRB to indicate it's the last TRB in the chain.
2642                  */
2643                 if (num_trbs > 1) {
2644                         field |= TRB_CHAIN;
2645                 } else {
2646                         /* FIXME - add check for ZERO_PACKET flag before this */
2647                         td->last_trb = ep_ring->enqueue;
2648                         field |= TRB_IOC;
2649                 }
2650                 remainder = xhci_td_remainder(urb->transfer_buffer_length -
2651                                 running_total);
2652                 length_field = TRB_LEN(trb_buff_len) |
2653                         remainder |
2654                         TRB_INTR_TARGET(0);
2655                 if (num_trbs > 1)
2656                         more_trbs_coming = true;
2657                 else
2658                         more_trbs_coming = false;
2659                 queue_trb(xhci, ep_ring, false, more_trbs_coming,
2660                                 lower_32_bits(addr),
2661                                 upper_32_bits(addr),
2662                                 length_field,
2663                                 /* We always want to know if the TRB was short,
2664                                  * or we won't get an event when it completes.
2665                                  * (Unless we use event data TRBs, which are a
2666                                  * waste of space and HC resources.)
2667                                  */
2668                                 field | TRB_ISP | TRB_TYPE(TRB_NORMAL));
2669                 --num_trbs;
2670                 running_total += trb_buff_len;
2671
2672                 /* Calculate length for next transfer */
2673                 addr += trb_buff_len;
2674                 trb_buff_len = urb->transfer_buffer_length - running_total;
2675                 if (trb_buff_len > TRB_MAX_BUFF_SIZE)
2676                         trb_buff_len = TRB_MAX_BUFF_SIZE;
2677         } while (running_total < urb->transfer_buffer_length);
2678
2679         check_trb_math(urb, num_trbs, running_total);
2680         giveback_first_trb(xhci, slot_id, ep_index, urb->stream_id,
2681                         start_cycle, start_trb, td);
2682         return 0;
2683 }
2684
2685 /* Caller must have locked xhci->lock */
2686 int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
2687                 struct urb *urb, int slot_id, unsigned int ep_index)
2688 {
2689         struct xhci_ring *ep_ring;
2690         int num_trbs;
2691         int ret;
2692         struct usb_ctrlrequest *setup;
2693         struct xhci_generic_trb *start_trb;
2694         int start_cycle;
2695         u32 field, length_field;
2696         struct urb_priv *urb_priv;
2697         struct xhci_td *td;
2698
2699         ep_ring = xhci_urb_to_transfer_ring(xhci, urb);
2700         if (!ep_ring)
2701                 return -EINVAL;
2702
2703         /*
2704          * Need to copy setup packet into setup TRB, so we can't use the setup
2705          * DMA address.
2706          */
2707         if (!urb->setup_packet)
2708                 return -EINVAL;
2709
2710         if (!in_interrupt())
2711                 xhci_dbg(xhci, "Queueing ctrl tx for slot id %d, ep %d\n",
2712                                 slot_id, ep_index);
2713         /* 1 TRB for setup, 1 for status */
2714         num_trbs = 2;
2715         /*
2716          * Don't need to check if we need additional event data and normal TRBs,
2717          * since data in control transfers will never get bigger than 16MB
2718          * XXX: can we get a buffer that crosses 64KB boundaries?
2719          */
2720         if (urb->transfer_buffer_length > 0)
2721                 num_trbs++;
2722         ret = prepare_transfer(xhci, xhci->devs[slot_id],
2723                         ep_index, urb->stream_id,
2724                         num_trbs, urb, 0, mem_flags);
2725         if (ret < 0)
2726                 return ret;
2727
2728         urb_priv = urb->hcpriv;
2729         td = urb_priv->td[0];
2730
2731         /*
2732          * Don't give the first TRB to the hardware (by toggling the cycle bit)
2733          * until we've finished creating all the other TRBs.  The ring's cycle
2734          * state may change as we enqueue the other TRBs, so save it too.
2735          */
2736         start_trb = &ep_ring->enqueue->generic;
2737         start_cycle = ep_ring->cycle_state;
2738
2739         /* Queue setup TRB - see section 6.4.1.2.1 */
2740         /* FIXME better way to translate setup_packet into two u32 fields? */
2741         setup = (struct usb_ctrlrequest *) urb->setup_packet;
2742         queue_trb(xhci, ep_ring, false, true,
2743                         /* FIXME endianness is probably going to bite my ass here. */
2744                         setup->bRequestType | setup->bRequest << 8 | setup->wValue << 16,
2745                         setup->wIndex | setup->wLength << 16,
2746                         TRB_LEN(8) | TRB_INTR_TARGET(0),
2747                         /* Immediate data in pointer */
2748                         TRB_IDT | TRB_TYPE(TRB_SETUP));
2749
2750         /* If there's data, queue data TRBs */
2751         field = 0;
2752         length_field = TRB_LEN(urb->transfer_buffer_length) |
2753                 xhci_td_remainder(urb->transfer_buffer_length) |
2754                 TRB_INTR_TARGET(0);
2755         if (urb->transfer_buffer_length > 0) {
2756                 if (setup->bRequestType & USB_DIR_IN)
2757                         field |= TRB_DIR_IN;
2758                 queue_trb(xhci, ep_ring, false, true,
2759                                 lower_32_bits(urb->transfer_dma),
2760                                 upper_32_bits(urb->transfer_dma),
2761                                 length_field,
2762                                 /* Event on short tx */
2763                                 field | TRB_ISP | TRB_TYPE(TRB_DATA) | ep_ring->cycle_state);
2764         }
2765
2766         /* Save the DMA address of the last TRB in the TD */
2767         td->last_trb = ep_ring->enqueue;
2768
2769         /* Queue status TRB - see Table 7 and sections 4.11.2.2 and 6.4.1.2.3 */
2770         /* If the device sent data, the status stage is an OUT transfer */
2771         if (urb->transfer_buffer_length > 0 && setup->bRequestType & USB_DIR_IN)
2772                 field = 0;
2773         else
2774                 field = TRB_DIR_IN;
2775         queue_trb(xhci, ep_ring, false, false,
2776                         0,
2777                         0,
2778                         TRB_INTR_TARGET(0),
2779                         /* Event on completion */
2780                         field | TRB_IOC | TRB_TYPE(TRB_STATUS) | ep_ring->cycle_state);
2781
2782         giveback_first_trb(xhci, slot_id, ep_index, 0,
2783                         start_cycle, start_trb, td);
2784         return 0;
2785 }
2786
2787 static int count_isoc_trbs_needed(struct xhci_hcd *xhci,
2788                 struct urb *urb, int i)
2789 {
2790         int num_trbs = 0;
2791         u64 addr, td_len, running_total;
2792
2793         addr = (u64) (urb->transfer_dma + urb->iso_frame_desc[i].offset);
2794         td_len = urb->iso_frame_desc[i].length;
2795
2796         running_total = TRB_MAX_BUFF_SIZE -
2797                         (addr & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
2798         if (running_total != 0)
2799                 num_trbs++;
2800
2801         while (running_total < td_len) {
2802                 num_trbs++;
2803                 running_total += TRB_MAX_BUFF_SIZE;
2804         }
2805
2806         return num_trbs;
2807 }
2808
2809 /* This is for isoc transfer */
2810 static int xhci_queue_isoc_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
2811                 struct urb *urb, int slot_id, unsigned int ep_index)
2812 {
2813         struct xhci_ring *ep_ring;
2814         struct urb_priv *urb_priv;
2815         struct xhci_td *td;
2816         int num_tds, trbs_per_td;
2817         struct xhci_generic_trb *start_trb;
2818         bool first_trb;
2819         int start_cycle;
2820         u32 field, length_field;
2821         int running_total, trb_buff_len, td_len, td_remain_len, ret;
2822         u64 start_addr, addr;
2823         int i, j;
2824
2825         ep_ring = xhci->devs[slot_id]->eps[ep_index].ring;
2826
2827         num_tds = urb->number_of_packets;
2828         if (num_tds < 1) {
2829                 xhci_dbg(xhci, "Isoc URB with zero packets?\n");
2830                 return -EINVAL;
2831         }
2832
2833         if (!in_interrupt())
2834                 dev_dbg(&urb->dev->dev, "ep %#x - urb len = %#x (%d),"
2835                                 " addr = %#llx, num_tds = %d\n",
2836                                 urb->ep->desc.bEndpointAddress,
2837                                 urb->transfer_buffer_length,
2838                                 urb->transfer_buffer_length,
2839                                 (unsigned long long)urb->transfer_dma,
2840                                 num_tds);
2841
2842         start_addr = (u64) urb->transfer_dma;
2843         start_trb = &ep_ring->enqueue->generic;
2844         start_cycle = ep_ring->cycle_state;
2845
2846         /* Queue the first TRB, even if it's zero-length */
2847         for (i = 0; i < num_tds; i++) {
2848                 first_trb = true;
2849
2850                 running_total = 0;
2851                 addr = start_addr + urb->iso_frame_desc[i].offset;
2852                 td_len = urb->iso_frame_desc[i].length;
2853                 td_remain_len = td_len;
2854
2855                 trbs_per_td = count_isoc_trbs_needed(xhci, urb, i);
2856
2857                 ret = prepare_transfer(xhci, xhci->devs[slot_id], ep_index,
2858                                 urb->stream_id, trbs_per_td, urb, i, mem_flags);
2859                 if (ret < 0)
2860                         return ret;
2861
2862                 urb_priv = urb->hcpriv;
2863                 td = urb_priv->td[i];
2864
2865                 for (j = 0; j < trbs_per_td; j++) {
2866                         u32 remainder = 0;
2867                         field = 0;
2868
2869                         if (first_trb) {
2870                                 /* Queue the isoc TRB */
2871                                 field |= TRB_TYPE(TRB_ISOC);
2872                                 /* Assume URB_ISO_ASAP is set */
2873                                 field |= TRB_SIA;
2874                                 if (i > 0)
2875                                         field |= ep_ring->cycle_state;
2876                                 first_trb = false;
2877                         } else {
2878                                 /* Queue other normal TRBs */
2879                                 field |= TRB_TYPE(TRB_NORMAL);
2880                                 field |= ep_ring->cycle_state;
2881                         }
2882
2883                         /* Chain all the TRBs together; clear the chain bit in
2884                          * the last TRB to indicate it's the last TRB in the
2885                          * chain.
2886                          */
2887                         if (j < trbs_per_td - 1) {
2888                                 field |= TRB_CHAIN;
2889                         } else {
2890                                 td->last_trb = ep_ring->enqueue;
2891                                 field |= TRB_IOC;
2892                         }
2893
2894                         /* Calculate TRB length */
2895                         trb_buff_len = TRB_MAX_BUFF_SIZE -
2896                                 (addr & ((1 << TRB_MAX_BUFF_SHIFT) - 1));
2897                         if (trb_buff_len > td_remain_len)
2898                                 trb_buff_len = td_remain_len;
2899
2900                         remainder = xhci_td_remainder(td_len - running_total);
2901                         length_field = TRB_LEN(trb_buff_len) |
2902                                 remainder |
2903                                 TRB_INTR_TARGET(0);
2904                         queue_trb(xhci, ep_ring, false, false,
2905                                 lower_32_bits(addr),
2906                                 upper_32_bits(addr),
2907                                 length_field,
2908                                 /* We always want to know if the TRB was short,
2909                                  * or we won't get an event when it completes.
2910                                  * (Unless we use event data TRBs, which are a
2911                                  * waste of space and HC resources.)
2912                                  */
2913                                 field | TRB_ISP);
2914                         running_total += trb_buff_len;
2915
2916                         addr += trb_buff_len;
2917                         td_remain_len -= trb_buff_len;
2918                 }
2919
2920                 /* Check TD length */
2921                 if (running_total != td_len) {
2922                         xhci_err(xhci, "ISOC TD length unmatch\n");
2923                         return -EINVAL;
2924                 }
2925         }
2926
2927         wmb();
2928         start_trb->field[3] |= start_cycle;
2929
2930         ring_ep_doorbell(xhci, slot_id, ep_index, urb->stream_id);
2931         return 0;
2932 }
2933
2934 /*
2935  * Check transfer ring to guarantee there is enough room for the urb.
2936  * Update ISO URB start_frame and interval.
2937  * Update interval as xhci_queue_intr_tx does. Just use xhci frame_index to
2938  * update the urb->start_frame by now.
2939  * Always assume URB_ISO_ASAP set, and NEVER use urb->start_frame as input.
2940  */
2941 int xhci_queue_isoc_tx_prepare(struct xhci_hcd *xhci, gfp_t mem_flags,
2942                 struct urb *urb, int slot_id, unsigned int ep_index)
2943 {
2944         struct xhci_virt_device *xdev;
2945         struct xhci_ring *ep_ring;
2946         struct xhci_ep_ctx *ep_ctx;
2947         int start_frame;
2948         int xhci_interval;
2949         int ep_interval;
2950         int num_tds, num_trbs, i;
2951         int ret;
2952
2953         xdev = xhci->devs[slot_id];
2954         ep_ring = xdev->eps[ep_index].ring;
2955         ep_ctx = xhci_get_ep_ctx(xhci, xdev->out_ctx, ep_index);
2956
2957         num_trbs = 0;
2958         num_tds = urb->number_of_packets;
2959         for (i = 0; i < num_tds; i++)
2960                 num_trbs += count_isoc_trbs_needed(xhci, urb, i);
2961
2962         /* Check the ring to guarantee there is enough room for the whole urb.
2963          * Do not insert any td of the urb to the ring if the check failed.
2964          */
2965         ret = prepare_ring(xhci, ep_ring, ep_ctx->ep_info & EP_STATE_MASK,
2966                                 num_trbs, mem_flags);
2967         if (ret)
2968                 return ret;
2969
2970         start_frame = xhci_readl(xhci, &xhci->run_regs->microframe_index);
2971         start_frame &= 0x3fff;
2972
2973         urb->start_frame = start_frame;
2974         if (urb->dev->speed == USB_SPEED_LOW ||
2975                         urb->dev->speed == USB_SPEED_FULL)
2976                 urb->start_frame >>= 3;
2977
2978         xhci_interval = EP_INTERVAL_TO_UFRAMES(ep_ctx->ep_info);
2979         ep_interval = urb->interval;
2980         /* Convert to microframes */
2981         if (urb->dev->speed == USB_SPEED_LOW ||
2982                         urb->dev->speed == USB_SPEED_FULL)
2983                 ep_interval *= 8;
2984         /* FIXME change this to a warning and a suggestion to use the new API
2985          * to set the polling interval (once the API is added).
2986          */
2987         if (xhci_interval != ep_interval) {
2988                 if (!printk_ratelimit())
2989                         dev_dbg(&urb->dev->dev, "Driver uses different interval"
2990                                         " (%d microframe%s) than xHCI "
2991                                         "(%d microframe%s)\n",
2992                                         ep_interval,
2993                                         ep_interval == 1 ? "" : "s",
2994                                         xhci_interval,
2995                                         xhci_interval == 1 ? "" : "s");
2996                 urb->interval = xhci_interval;
2997                 /* Convert back to frames for LS/FS devices */
2998                 if (urb->dev->speed == USB_SPEED_LOW ||
2999                                 urb->dev->speed == USB_SPEED_FULL)
3000                         urb->interval /= 8;
3001         }
3002         return xhci_queue_isoc_tx(xhci, GFP_ATOMIC, urb, slot_id, ep_index);
3003 }
3004
3005 /****           Command Ring Operations         ****/
3006
3007 /* Generic function for queueing a command TRB on the command ring.
3008  * Check to make sure there's room on the command ring for one command TRB.
3009  * Also check that there's room reserved for commands that must not fail.
3010  * If this is a command that must not fail, meaning command_must_succeed = TRUE,
3011  * then only check for the number of reserved spots.
3012  * Don't decrement xhci->cmd_ring_reserved_trbs after we've queued the TRB
3013  * because the command event handler may want to resubmit a failed command.
3014  */
3015 static int queue_command(struct xhci_hcd *xhci, u32 field1, u32 field2,
3016                 u32 field3, u32 field4, bool command_must_succeed)
3017 {
3018         int reserved_trbs = xhci->cmd_ring_reserved_trbs;
3019         int ret;
3020
3021         if (!command_must_succeed)
3022                 reserved_trbs++;
3023
3024         ret = prepare_ring(xhci, xhci->cmd_ring, EP_STATE_RUNNING,
3025                         reserved_trbs, GFP_ATOMIC);
3026         if (ret < 0) {
3027                 xhci_err(xhci, "ERR: No room for command on command ring\n");
3028                 if (command_must_succeed)
3029                         xhci_err(xhci, "ERR: Reserved TRB counting for "
3030                                         "unfailable commands failed.\n");
3031                 return ret;
3032         }
3033         queue_trb(xhci, xhci->cmd_ring, false, false, field1, field2, field3,
3034                         field4 | xhci->cmd_ring->cycle_state);
3035         return 0;
3036 }
3037
3038 /* Queue a no-op command on the command ring */
3039 static int queue_cmd_noop(struct xhci_hcd *xhci)
3040 {
3041         return queue_command(xhci, 0, 0, 0, TRB_TYPE(TRB_CMD_NOOP), false);
3042 }
3043
3044 /*
3045  * Place a no-op command on the command ring to test the command and
3046  * event ring.
3047  */
3048 void *xhci_setup_one_noop(struct xhci_hcd *xhci)
3049 {
3050         if (queue_cmd_noop(xhci) < 0)
3051                 return NULL;
3052         xhci->noops_submitted++;
3053         return xhci_ring_cmd_db;
3054 }
3055
3056 /* Queue a slot enable or disable request on the command ring */
3057 int xhci_queue_slot_control(struct xhci_hcd *xhci, u32 trb_type, u32 slot_id)
3058 {
3059         return queue_command(xhci, 0, 0, 0,
3060                         TRB_TYPE(trb_type) | SLOT_ID_FOR_TRB(slot_id), false);
3061 }
3062
3063 /* Queue an address device command TRB */
3064 int xhci_queue_address_device(struct xhci_hcd *xhci, dma_addr_t in_ctx_ptr,
3065                 u32 slot_id)
3066 {
3067         return queue_command(xhci, lower_32_bits(in_ctx_ptr),
3068                         upper_32_bits(in_ctx_ptr), 0,
3069                         TRB_TYPE(TRB_ADDR_DEV) | SLOT_ID_FOR_TRB(slot_id),
3070                         false);
3071 }
3072
3073 int xhci_queue_vendor_command(struct xhci_hcd *xhci,
3074                 u32 field1, u32 field2, u32 field3, u32 field4)
3075 {
3076         return queue_command(xhci, field1, field2, field3, field4, false);
3077 }
3078
3079 /* Queue a reset device command TRB */
3080 int xhci_queue_reset_device(struct xhci_hcd *xhci, u32 slot_id)
3081 {
3082         return queue_command(xhci, 0, 0, 0,
3083                         TRB_TYPE(TRB_RESET_DEV) | SLOT_ID_FOR_TRB(slot_id),
3084                         false);
3085 }
3086
3087 /* Queue a configure endpoint command TRB */
3088 int xhci_queue_configure_endpoint(struct xhci_hcd *xhci, dma_addr_t in_ctx_ptr,
3089                 u32 slot_id, bool command_must_succeed)
3090 {
3091         return queue_command(xhci, lower_32_bits(in_ctx_ptr),
3092                         upper_32_bits(in_ctx_ptr), 0,
3093                         TRB_TYPE(TRB_CONFIG_EP) | SLOT_ID_FOR_TRB(slot_id),
3094                         command_must_succeed);
3095 }
3096
3097 /* Queue an evaluate context command TRB */
3098 int xhci_queue_evaluate_context(struct xhci_hcd *xhci, dma_addr_t in_ctx_ptr,
3099                 u32 slot_id)
3100 {
3101         return queue_command(xhci, lower_32_bits(in_ctx_ptr),
3102                         upper_32_bits(in_ctx_ptr), 0,
3103                         TRB_TYPE(TRB_EVAL_CONTEXT) | SLOT_ID_FOR_TRB(slot_id),
3104                         false);
3105 }
3106
3107 int xhci_queue_stop_endpoint(struct xhci_hcd *xhci, int slot_id,
3108                 unsigned int ep_index)
3109 {
3110         u32 trb_slot_id = SLOT_ID_FOR_TRB(slot_id);
3111         u32 trb_ep_index = EP_ID_FOR_TRB(ep_index);
3112         u32 type = TRB_TYPE(TRB_STOP_RING);
3113
3114         return queue_command(xhci, 0, 0, 0,
3115                         trb_slot_id | trb_ep_index | type, false);
3116 }
3117
3118 /* Set Transfer Ring Dequeue Pointer command.
3119  * This should not be used for endpoints that have streams enabled.
3120  */
3121 static int queue_set_tr_deq(struct xhci_hcd *xhci, int slot_id,
3122                 unsigned int ep_index, unsigned int stream_id,
3123                 struct xhci_segment *deq_seg,
3124                 union xhci_trb *deq_ptr, u32 cycle_state)
3125 {
3126         dma_addr_t addr;
3127         u32 trb_slot_id = SLOT_ID_FOR_TRB(slot_id);
3128         u32 trb_ep_index = EP_ID_FOR_TRB(ep_index);
3129         u32 trb_stream_id = STREAM_ID_FOR_TRB(stream_id);
3130         u32 type = TRB_TYPE(TRB_SET_DEQ);
3131
3132         addr = xhci_trb_virt_to_dma(deq_seg, deq_ptr);
3133         if (addr == 0) {
3134                 xhci_warn(xhci, "WARN Cannot submit Set TR Deq Ptr\n");
3135                 xhci_warn(xhci, "WARN deq seg = %p, deq pt = %p\n",
3136                                 deq_seg, deq_ptr);
3137                 return 0;
3138         }
3139         return queue_command(xhci, lower_32_bits(addr) | cycle_state,
3140                         upper_32_bits(addr), trb_stream_id,
3141                         trb_slot_id | trb_ep_index | type, false);
3142 }
3143
3144 int xhci_queue_reset_ep(struct xhci_hcd *xhci, int slot_id,
3145                 unsigned int ep_index)
3146 {
3147         u32 trb_slot_id = SLOT_ID_FOR_TRB(slot_id);
3148         u32 trb_ep_index = EP_ID_FOR_TRB(ep_index);
3149         u32 type = TRB_TYPE(TRB_RESET_EP);
3150
3151         return queue_command(xhci, 0, 0, 0, trb_slot_id | trb_ep_index | type,
3152                         false);
3153 }