xref: /linux/drivers/usb/host/xhci-ring.c (revision 98838d95075a5295f3478ceba18bcccf472e30f4)
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 <linux/dma-mapping.h>
70 #include "xhci.h"
71 #include "xhci-trace.h"
72 #include "xhci-mtk.h"
73 
74 /*
75  * Returns zero if the TRB isn't in this segment, otherwise it returns the DMA
76  * address of the TRB.
77  */
78 dma_addr_t xhci_trb_virt_to_dma(struct xhci_segment *seg,
79 		union xhci_trb *trb)
80 {
81 	unsigned long segment_offset;
82 
83 	if (!seg || !trb || trb < seg->trbs)
84 		return 0;
85 	/* offset in TRBs */
86 	segment_offset = trb - seg->trbs;
87 	if (segment_offset >= TRBS_PER_SEGMENT)
88 		return 0;
89 	return seg->dma + (segment_offset * sizeof(*trb));
90 }
91 
92 static bool trb_is_link(union xhci_trb *trb)
93 {
94 	return TRB_TYPE_LINK_LE32(trb->link.control);
95 }
96 
97 static bool last_trb_on_seg(struct xhci_segment *seg, union xhci_trb *trb)
98 {
99 	return trb == &seg->trbs[TRBS_PER_SEGMENT - 1];
100 }
101 
102 static bool last_trb_on_ring(struct xhci_ring *ring,
103 			struct xhci_segment *seg, union xhci_trb *trb)
104 {
105 	return last_trb_on_seg(seg, trb) && (seg->next == ring->first_seg);
106 }
107 
108 static bool link_trb_toggles_cycle(union xhci_trb *trb)
109 {
110 	return le32_to_cpu(trb->link.control) & LINK_TOGGLE;
111 }
112 
113 /* Updates trb to point to the next TRB in the ring, and updates seg if the next
114  * TRB is in a new segment.  This does not skip over link TRBs, and it does not
115  * effect the ring dequeue or enqueue pointers.
116  */
117 static void next_trb(struct xhci_hcd *xhci,
118 		struct xhci_ring *ring,
119 		struct xhci_segment **seg,
120 		union xhci_trb **trb)
121 {
122 	if (trb_is_link(*trb)) {
123 		*seg = (*seg)->next;
124 		*trb = ((*seg)->trbs);
125 	} else {
126 		(*trb)++;
127 	}
128 }
129 
130 /*
131  * See Cycle bit rules. SW is the consumer for the event ring only.
132  * Don't make a ring full of link TRBs.  That would be dumb and this would loop.
133  */
134 static void inc_deq(struct xhci_hcd *xhci, struct xhci_ring *ring)
135 {
136 	ring->deq_updates++;
137 
138 	/* event ring doesn't have link trbs, check for last trb */
139 	if (ring->type == TYPE_EVENT) {
140 		if (!last_trb_on_seg(ring->deq_seg, ring->dequeue)) {
141 			ring->dequeue++;
142 			return;
143 		}
144 		if (last_trb_on_ring(ring, ring->deq_seg, ring->dequeue))
145 			ring->cycle_state ^= 1;
146 		ring->deq_seg = ring->deq_seg->next;
147 		ring->dequeue = ring->deq_seg->trbs;
148 		return;
149 	}
150 
151 	/* All other rings have link trbs */
152 	if (!trb_is_link(ring->dequeue)) {
153 		ring->dequeue++;
154 		ring->num_trbs_free++;
155 	}
156 	while (trb_is_link(ring->dequeue)) {
157 		ring->deq_seg = ring->deq_seg->next;
158 		ring->dequeue = ring->deq_seg->trbs;
159 	}
160 	return;
161 }
162 
163 /*
164  * See Cycle bit rules. SW is the consumer for the event ring only.
165  * Don't make a ring full of link TRBs.  That would be dumb and this would loop.
166  *
167  * If we've just enqueued a TRB that is in the middle of a TD (meaning the
168  * chain bit is set), then set the chain bit in all the following link TRBs.
169  * If we've enqueued the last TRB in a TD, make sure the following link TRBs
170  * have their chain bit cleared (so that each Link TRB is a separate TD).
171  *
172  * Section 6.4.4.1 of the 0.95 spec says link TRBs cannot have the chain bit
173  * set, but other sections talk about dealing with the chain bit set.  This was
174  * fixed in the 0.96 specification errata, but we have to assume that all 0.95
175  * xHCI hardware can't handle the chain bit being cleared on a link TRB.
176  *
177  * @more_trbs_coming:	Will you enqueue more TRBs before calling
178  *			prepare_transfer()?
179  */
180 static void inc_enq(struct xhci_hcd *xhci, struct xhci_ring *ring,
181 			bool more_trbs_coming)
182 {
183 	u32 chain;
184 	union xhci_trb *next;
185 
186 	chain = le32_to_cpu(ring->enqueue->generic.field[3]) & TRB_CHAIN;
187 	/* If this is not event ring, there is one less usable TRB */
188 	if (!trb_is_link(ring->enqueue))
189 		ring->num_trbs_free--;
190 	next = ++(ring->enqueue);
191 
192 	ring->enq_updates++;
193 	/* Update the dequeue pointer further if that was a link TRB */
194 	while (trb_is_link(next)) {
195 
196 		/*
197 		 * If the caller doesn't plan on enqueueing more TDs before
198 		 * ringing the doorbell, then we don't want to give the link TRB
199 		 * to the hardware just yet. We'll give the link TRB back in
200 		 * prepare_ring() just before we enqueue the TD at the top of
201 		 * the ring.
202 		 */
203 		if (!chain && !more_trbs_coming)
204 			break;
205 
206 		/* If we're not dealing with 0.95 hardware or isoc rings on
207 		 * AMD 0.96 host, carry over the chain bit of the previous TRB
208 		 * (which may mean the chain bit is cleared).
209 		 */
210 		if (!(ring->type == TYPE_ISOC &&
211 		      (xhci->quirks & XHCI_AMD_0x96_HOST)) &&
212 		    !xhci_link_trb_quirk(xhci)) {
213 			next->link.control &= cpu_to_le32(~TRB_CHAIN);
214 			next->link.control |= cpu_to_le32(chain);
215 		}
216 		/* Give this link TRB to the hardware */
217 		wmb();
218 		next->link.control ^= cpu_to_le32(TRB_CYCLE);
219 
220 		/* Toggle the cycle bit after the last ring segment. */
221 		if (link_trb_toggles_cycle(next))
222 			ring->cycle_state ^= 1;
223 
224 		ring->enq_seg = ring->enq_seg->next;
225 		ring->enqueue = ring->enq_seg->trbs;
226 		next = ring->enqueue;
227 	}
228 }
229 
230 /*
231  * Check to see if there's room to enqueue num_trbs on the ring and make sure
232  * enqueue pointer will not advance into dequeue segment. See rules above.
233  */
234 static inline int room_on_ring(struct xhci_hcd *xhci, struct xhci_ring *ring,
235 		unsigned int num_trbs)
236 {
237 	int num_trbs_in_deq_seg;
238 
239 	if (ring->num_trbs_free < num_trbs)
240 		return 0;
241 
242 	if (ring->type != TYPE_COMMAND && ring->type != TYPE_EVENT) {
243 		num_trbs_in_deq_seg = ring->dequeue - ring->deq_seg->trbs;
244 		if (ring->num_trbs_free < num_trbs + num_trbs_in_deq_seg)
245 			return 0;
246 	}
247 
248 	return 1;
249 }
250 
251 /* Ring the host controller doorbell after placing a command on the ring */
252 void xhci_ring_cmd_db(struct xhci_hcd *xhci)
253 {
254 	if (!(xhci->cmd_ring_state & CMD_RING_STATE_RUNNING))
255 		return;
256 
257 	xhci_dbg(xhci, "// Ding dong!\n");
258 	writel(DB_VALUE_HOST, &xhci->dba->doorbell[0]);
259 	/* Flush PCI posted writes */
260 	readl(&xhci->dba->doorbell[0]);
261 }
262 
263 static int xhci_abort_cmd_ring(struct xhci_hcd *xhci)
264 {
265 	u64 temp_64;
266 	int ret;
267 
268 	xhci_dbg(xhci, "Abort command ring\n");
269 
270 	temp_64 = xhci_read_64(xhci, &xhci->op_regs->cmd_ring);
271 	xhci->cmd_ring_state = CMD_RING_STATE_ABORTED;
272 
273 	/*
274 	 * Writing the CMD_RING_ABORT bit should cause a cmd completion event,
275 	 * however on some host hw the CMD_RING_RUNNING bit is correctly cleared
276 	 * but the completion event in never sent. Use the cmd timeout timer to
277 	 * handle those cases. Use twice the time to cover the bit polling retry
278 	 */
279 	mod_timer(&xhci->cmd_timer, jiffies + (2 * XHCI_CMD_DEFAULT_TIMEOUT));
280 	xhci_write_64(xhci, temp_64 | CMD_RING_ABORT,
281 			&xhci->op_regs->cmd_ring);
282 
283 	/* Section 4.6.1.2 of xHCI 1.0 spec says software should
284 	 * time the completion od all xHCI commands, including
285 	 * the Command Abort operation. If software doesn't see
286 	 * CRR negated in a timely manner (e.g. longer than 5
287 	 * seconds), then it should assume that the there are
288 	 * larger problems with the xHC and assert HCRST.
289 	 */
290 	ret = xhci_handshake(&xhci->op_regs->cmd_ring,
291 			CMD_RING_RUNNING, 0, 5 * 1000 * 1000);
292 	if (ret < 0) {
293 		/* we are about to kill xhci, give it one more chance */
294 		xhci_write_64(xhci, temp_64 | CMD_RING_ABORT,
295 			      &xhci->op_regs->cmd_ring);
296 		udelay(1000);
297 		ret = xhci_handshake(&xhci->op_regs->cmd_ring,
298 				     CMD_RING_RUNNING, 0, 3 * 1000 * 1000);
299 		if (ret == 0)
300 			return 0;
301 
302 		xhci_err(xhci, "Stopped the command ring failed, "
303 				"maybe the host is dead\n");
304 		del_timer(&xhci->cmd_timer);
305 		xhci->xhc_state |= XHCI_STATE_DYING;
306 		xhci_quiesce(xhci);
307 		xhci_halt(xhci);
308 		return -ESHUTDOWN;
309 	}
310 
311 	return 0;
312 }
313 
314 void xhci_ring_ep_doorbell(struct xhci_hcd *xhci,
315 		unsigned int slot_id,
316 		unsigned int ep_index,
317 		unsigned int stream_id)
318 {
319 	__le32 __iomem *db_addr = &xhci->dba->doorbell[slot_id];
320 	struct xhci_virt_ep *ep = &xhci->devs[slot_id]->eps[ep_index];
321 	unsigned int ep_state = ep->ep_state;
322 
323 	/* Don't ring the doorbell for this endpoint if there are pending
324 	 * cancellations because we don't want to interrupt processing.
325 	 * We don't want to restart any stream rings if there's a set dequeue
326 	 * pointer command pending because the device can choose to start any
327 	 * stream once the endpoint is on the HW schedule.
328 	 */
329 	if ((ep_state & EP_HALT_PENDING) || (ep_state & SET_DEQ_PENDING) ||
330 	    (ep_state & EP_HALTED))
331 		return;
332 	writel(DB_VALUE(ep_index, stream_id), db_addr);
333 	/* The CPU has better things to do at this point than wait for a
334 	 * write-posting flush.  It'll get there soon enough.
335 	 */
336 }
337 
338 /* Ring the doorbell for any rings with pending URBs */
339 static void ring_doorbell_for_active_rings(struct xhci_hcd *xhci,
340 		unsigned int slot_id,
341 		unsigned int ep_index)
342 {
343 	unsigned int stream_id;
344 	struct xhci_virt_ep *ep;
345 
346 	ep = &xhci->devs[slot_id]->eps[ep_index];
347 
348 	/* A ring has pending URBs if its TD list is not empty */
349 	if (!(ep->ep_state & EP_HAS_STREAMS)) {
350 		if (ep->ring && !(list_empty(&ep->ring->td_list)))
351 			xhci_ring_ep_doorbell(xhci, slot_id, ep_index, 0);
352 		return;
353 	}
354 
355 	for (stream_id = 1; stream_id < ep->stream_info->num_streams;
356 			stream_id++) {
357 		struct xhci_stream_info *stream_info = ep->stream_info;
358 		if (!list_empty(&stream_info->stream_rings[stream_id]->td_list))
359 			xhci_ring_ep_doorbell(xhci, slot_id, ep_index,
360 						stream_id);
361 	}
362 }
363 
364 /* Get the right ring for the given slot_id, ep_index and stream_id.
365  * If the endpoint supports streams, boundary check the URB's stream ID.
366  * If the endpoint doesn't support streams, return the singular endpoint ring.
367  */
368 struct xhci_ring *xhci_triad_to_transfer_ring(struct xhci_hcd *xhci,
369 		unsigned int slot_id, unsigned int ep_index,
370 		unsigned int stream_id)
371 {
372 	struct xhci_virt_ep *ep;
373 
374 	ep = &xhci->devs[slot_id]->eps[ep_index];
375 	/* Common case: no streams */
376 	if (!(ep->ep_state & EP_HAS_STREAMS))
377 		return ep->ring;
378 
379 	if (stream_id == 0) {
380 		xhci_warn(xhci,
381 				"WARN: Slot ID %u, ep index %u has streams, "
382 				"but URB has no stream ID.\n",
383 				slot_id, ep_index);
384 		return NULL;
385 	}
386 
387 	if (stream_id < ep->stream_info->num_streams)
388 		return ep->stream_info->stream_rings[stream_id];
389 
390 	xhci_warn(xhci,
391 			"WARN: Slot ID %u, ep index %u has "
392 			"stream IDs 1 to %u allocated, "
393 			"but stream ID %u is requested.\n",
394 			slot_id, ep_index,
395 			ep->stream_info->num_streams - 1,
396 			stream_id);
397 	return NULL;
398 }
399 
400 /*
401  * Move the xHC's endpoint ring dequeue pointer past cur_td.
402  * Record the new state of the xHC's endpoint ring dequeue segment,
403  * dequeue pointer, and new consumer cycle state in state.
404  * Update our internal representation of the ring's dequeue pointer.
405  *
406  * We do this in three jumps:
407  *  - First we update our new ring state to be the same as when the xHC stopped.
408  *  - Then we traverse the ring to find the segment that contains
409  *    the last TRB in the TD.  We toggle the xHC's new cycle state when we pass
410  *    any link TRBs with the toggle cycle bit set.
411  *  - Finally we move the dequeue state one TRB further, toggling the cycle bit
412  *    if we've moved it past a link TRB with the toggle cycle bit set.
413  *
414  * Some of the uses of xhci_generic_trb are grotty, but if they're done
415  * with correct __le32 accesses they should work fine.  Only users of this are
416  * in here.
417  */
418 void xhci_find_new_dequeue_state(struct xhci_hcd *xhci,
419 		unsigned int slot_id, unsigned int ep_index,
420 		unsigned int stream_id, struct xhci_td *cur_td,
421 		struct xhci_dequeue_state *state)
422 {
423 	struct xhci_virt_device *dev = xhci->devs[slot_id];
424 	struct xhci_virt_ep *ep = &dev->eps[ep_index];
425 	struct xhci_ring *ep_ring;
426 	struct xhci_segment *new_seg;
427 	union xhci_trb *new_deq;
428 	dma_addr_t addr;
429 	u64 hw_dequeue;
430 	bool cycle_found = false;
431 	bool td_last_trb_found = false;
432 
433 	ep_ring = xhci_triad_to_transfer_ring(xhci, slot_id,
434 			ep_index, stream_id);
435 	if (!ep_ring) {
436 		xhci_warn(xhci, "WARN can't find new dequeue state "
437 				"for invalid stream ID %u.\n",
438 				stream_id);
439 		return;
440 	}
441 
442 	/* Dig out the cycle state saved by the xHC during the stop ep cmd */
443 	xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
444 			"Finding endpoint context");
445 	/* 4.6.9 the css flag is written to the stream context for streams */
446 	if (ep->ep_state & EP_HAS_STREAMS) {
447 		struct xhci_stream_ctx *ctx =
448 			&ep->stream_info->stream_ctx_array[stream_id];
449 		hw_dequeue = le64_to_cpu(ctx->stream_ring);
450 	} else {
451 		struct xhci_ep_ctx *ep_ctx
452 			= xhci_get_ep_ctx(xhci, dev->out_ctx, ep_index);
453 		hw_dequeue = le64_to_cpu(ep_ctx->deq);
454 	}
455 
456 	new_seg = ep_ring->deq_seg;
457 	new_deq = ep_ring->dequeue;
458 	state->new_cycle_state = hw_dequeue & 0x1;
459 
460 	/*
461 	 * We want to find the pointer, segment and cycle state of the new trb
462 	 * (the one after current TD's last_trb). We know the cycle state at
463 	 * hw_dequeue, so walk the ring until both hw_dequeue and last_trb are
464 	 * found.
465 	 */
466 	do {
467 		if (!cycle_found && xhci_trb_virt_to_dma(new_seg, new_deq)
468 		    == (dma_addr_t)(hw_dequeue & ~0xf)) {
469 			cycle_found = true;
470 			if (td_last_trb_found)
471 				break;
472 		}
473 		if (new_deq == cur_td->last_trb)
474 			td_last_trb_found = true;
475 
476 		if (cycle_found &&
477 		    TRB_TYPE_LINK_LE32(new_deq->generic.field[3]) &&
478 		    new_deq->generic.field[3] & cpu_to_le32(LINK_TOGGLE))
479 			state->new_cycle_state ^= 0x1;
480 
481 		next_trb(xhci, ep_ring, &new_seg, &new_deq);
482 
483 		/* Search wrapped around, bail out */
484 		if (new_deq == ep->ring->dequeue) {
485 			xhci_err(xhci, "Error: Failed finding new dequeue state\n");
486 			state->new_deq_seg = NULL;
487 			state->new_deq_ptr = NULL;
488 			return;
489 		}
490 
491 	} while (!cycle_found || !td_last_trb_found);
492 
493 	state->new_deq_seg = new_seg;
494 	state->new_deq_ptr = new_deq;
495 
496 	/* Don't update the ring cycle state for the producer (us). */
497 	xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
498 			"Cycle state = 0x%x", state->new_cycle_state);
499 
500 	xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
501 			"New dequeue segment = %p (virtual)",
502 			state->new_deq_seg);
503 	addr = xhci_trb_virt_to_dma(state->new_deq_seg, state->new_deq_ptr);
504 	xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
505 			"New dequeue pointer = 0x%llx (DMA)",
506 			(unsigned long long) addr);
507 }
508 
509 /* flip_cycle means flip the cycle bit of all but the first and last TRB.
510  * (The last TRB actually points to the ring enqueue pointer, which is not part
511  * of this TD.)  This is used to remove partially enqueued isoc TDs from a ring.
512  */
513 static void td_to_noop(struct xhci_hcd *xhci, struct xhci_ring *ep_ring,
514 		struct xhci_td *cur_td, bool flip_cycle)
515 {
516 	struct xhci_segment *cur_seg;
517 	union xhci_trb *cur_trb;
518 
519 	for (cur_seg = cur_td->start_seg, cur_trb = cur_td->first_trb;
520 			true;
521 			next_trb(xhci, ep_ring, &cur_seg, &cur_trb)) {
522 		if (TRB_TYPE_LINK_LE32(cur_trb->generic.field[3])) {
523 			/* Unchain any chained Link TRBs, but
524 			 * leave the pointers intact.
525 			 */
526 			cur_trb->generic.field[3] &= cpu_to_le32(~TRB_CHAIN);
527 			/* Flip the cycle bit (link TRBs can't be the first
528 			 * or last TRB).
529 			 */
530 			if (flip_cycle)
531 				cur_trb->generic.field[3] ^=
532 					cpu_to_le32(TRB_CYCLE);
533 			xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
534 					"Cancel (unchain) link TRB");
535 			xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
536 					"Address = %p (0x%llx dma); "
537 					"in seg %p (0x%llx dma)",
538 					cur_trb,
539 					(unsigned long long)xhci_trb_virt_to_dma(cur_seg, cur_trb),
540 					cur_seg,
541 					(unsigned long long)cur_seg->dma);
542 		} else {
543 			cur_trb->generic.field[0] = 0;
544 			cur_trb->generic.field[1] = 0;
545 			cur_trb->generic.field[2] = 0;
546 			/* Preserve only the cycle bit of this TRB */
547 			cur_trb->generic.field[3] &= cpu_to_le32(TRB_CYCLE);
548 			/* Flip the cycle bit except on the first or last TRB */
549 			if (flip_cycle && cur_trb != cur_td->first_trb &&
550 					cur_trb != cur_td->last_trb)
551 				cur_trb->generic.field[3] ^=
552 					cpu_to_le32(TRB_CYCLE);
553 			cur_trb->generic.field[3] |= cpu_to_le32(
554 				TRB_TYPE(TRB_TR_NOOP));
555 			xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
556 					"TRB to noop at offset 0x%llx",
557 					(unsigned long long)
558 					xhci_trb_virt_to_dma(cur_seg, cur_trb));
559 		}
560 		if (cur_trb == cur_td->last_trb)
561 			break;
562 	}
563 }
564 
565 static void xhci_stop_watchdog_timer_in_irq(struct xhci_hcd *xhci,
566 		struct xhci_virt_ep *ep)
567 {
568 	ep->ep_state &= ~EP_HALT_PENDING;
569 	/* Can't del_timer_sync in interrupt, so we attempt to cancel.  If the
570 	 * timer is running on another CPU, we don't decrement stop_cmds_pending
571 	 * (since we didn't successfully stop the watchdog timer).
572 	 */
573 	if (del_timer(&ep->stop_cmd_timer))
574 		ep->stop_cmds_pending--;
575 }
576 
577 /* Must be called with xhci->lock held in interrupt context */
578 static void xhci_giveback_urb_in_irq(struct xhci_hcd *xhci,
579 		struct xhci_td *cur_td, int status)
580 {
581 	struct usb_hcd *hcd;
582 	struct urb	*urb;
583 	struct urb_priv	*urb_priv;
584 
585 	urb = cur_td->urb;
586 	urb_priv = urb->hcpriv;
587 	urb_priv->td_cnt++;
588 	hcd = bus_to_hcd(urb->dev->bus);
589 
590 	/* Only giveback urb when this is the last td in urb */
591 	if (urb_priv->td_cnt == urb_priv->length) {
592 		if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
593 			xhci_to_hcd(xhci)->self.bandwidth_isoc_reqs--;
594 			if (xhci_to_hcd(xhci)->self.bandwidth_isoc_reqs	== 0) {
595 				if (xhci->quirks & XHCI_AMD_PLL_FIX)
596 					usb_amd_quirk_pll_enable();
597 			}
598 		}
599 		usb_hcd_unlink_urb_from_ep(hcd, urb);
600 
601 		spin_unlock(&xhci->lock);
602 		usb_hcd_giveback_urb(hcd, urb, status);
603 		xhci_urb_free_priv(urb_priv);
604 		spin_lock(&xhci->lock);
605 	}
606 }
607 
608 void xhci_unmap_td_bounce_buffer(struct xhci_hcd *xhci, struct xhci_ring *ring,
609 				 struct xhci_td *td)
610 {
611 	struct device *dev = xhci_to_hcd(xhci)->self.controller;
612 	struct xhci_segment *seg = td->bounce_seg;
613 	struct urb *urb = td->urb;
614 
615 	if (!seg || !urb)
616 		return;
617 
618 	if (usb_urb_dir_out(urb)) {
619 		dma_unmap_single(dev, seg->bounce_dma, ring->bounce_buf_len,
620 				 DMA_TO_DEVICE);
621 		return;
622 	}
623 
624 	/* for in tranfers we need to copy the data from bounce to sg */
625 	sg_pcopy_from_buffer(urb->sg, urb->num_mapped_sgs, seg->bounce_buf,
626 			     seg->bounce_len, seg->bounce_offs);
627 	dma_unmap_single(dev, seg->bounce_dma, ring->bounce_buf_len,
628 			 DMA_FROM_DEVICE);
629 	seg->bounce_len = 0;
630 	seg->bounce_offs = 0;
631 }
632 
633 /*
634  * When we get a command completion for a Stop Endpoint Command, we need to
635  * unlink any cancelled TDs from the ring.  There are two ways to do that:
636  *
637  *  1. If the HW was in the middle of processing the TD that needs to be
638  *     cancelled, then we must move the ring's dequeue pointer past the last TRB
639  *     in the TD with a Set Dequeue Pointer Command.
640  *  2. Otherwise, we turn all the TRBs in the TD into No-op TRBs (with the chain
641  *     bit cleared) so that the HW will skip over them.
642  */
643 static void xhci_handle_cmd_stop_ep(struct xhci_hcd *xhci, int slot_id,
644 		union xhci_trb *trb, struct xhci_event_cmd *event)
645 {
646 	unsigned int ep_index;
647 	struct xhci_ring *ep_ring;
648 	struct xhci_virt_ep *ep;
649 	struct list_head *entry;
650 	struct xhci_td *cur_td = NULL;
651 	struct xhci_td *last_unlinked_td;
652 
653 	struct xhci_dequeue_state deq_state;
654 
655 	if (unlikely(TRB_TO_SUSPEND_PORT(le32_to_cpu(trb->generic.field[3])))) {
656 		if (!xhci->devs[slot_id])
657 			xhci_warn(xhci, "Stop endpoint command "
658 				"completion for disabled slot %u\n",
659 				slot_id);
660 		return;
661 	}
662 
663 	memset(&deq_state, 0, sizeof(deq_state));
664 	ep_index = TRB_TO_EP_INDEX(le32_to_cpu(trb->generic.field[3]));
665 	ep = &xhci->devs[slot_id]->eps[ep_index];
666 
667 	if (list_empty(&ep->cancelled_td_list)) {
668 		xhci_stop_watchdog_timer_in_irq(xhci, ep);
669 		ep->stopped_td = NULL;
670 		ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
671 		return;
672 	}
673 
674 	/* Fix up the ep ring first, so HW stops executing cancelled TDs.
675 	 * We have the xHCI lock, so nothing can modify this list until we drop
676 	 * it.  We're also in the event handler, so we can't get re-interrupted
677 	 * if another Stop Endpoint command completes
678 	 */
679 	list_for_each(entry, &ep->cancelled_td_list) {
680 		cur_td = list_entry(entry, struct xhci_td, cancelled_td_list);
681 		xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
682 				"Removing canceled TD starting at 0x%llx (dma).",
683 				(unsigned long long)xhci_trb_virt_to_dma(
684 					cur_td->start_seg, cur_td->first_trb));
685 		ep_ring = xhci_urb_to_transfer_ring(xhci, cur_td->urb);
686 		if (!ep_ring) {
687 			/* This shouldn't happen unless a driver is mucking
688 			 * with the stream ID after submission.  This will
689 			 * leave the TD on the hardware ring, and the hardware
690 			 * will try to execute it, and may access a buffer
691 			 * that has already been freed.  In the best case, the
692 			 * hardware will execute it, and the event handler will
693 			 * ignore the completion event for that TD, since it was
694 			 * removed from the td_list for that endpoint.  In
695 			 * short, don't muck with the stream ID after
696 			 * submission.
697 			 */
698 			xhci_warn(xhci, "WARN Cancelled URB %p "
699 					"has invalid stream ID %u.\n",
700 					cur_td->urb,
701 					cur_td->urb->stream_id);
702 			goto remove_finished_td;
703 		}
704 		/*
705 		 * If we stopped on the TD we need to cancel, then we have to
706 		 * move the xHC endpoint ring dequeue pointer past this TD.
707 		 */
708 		if (cur_td == ep->stopped_td)
709 			xhci_find_new_dequeue_state(xhci, slot_id, ep_index,
710 					cur_td->urb->stream_id,
711 					cur_td, &deq_state);
712 		else
713 			td_to_noop(xhci, ep_ring, cur_td, false);
714 remove_finished_td:
715 		/*
716 		 * The event handler won't see a completion for this TD anymore,
717 		 * so remove it from the endpoint ring's TD list.  Keep it in
718 		 * the cancelled TD list for URB completion later.
719 		 */
720 		list_del_init(&cur_td->td_list);
721 	}
722 	last_unlinked_td = cur_td;
723 	xhci_stop_watchdog_timer_in_irq(xhci, ep);
724 
725 	/* If necessary, queue a Set Transfer Ring Dequeue Pointer command */
726 	if (deq_state.new_deq_ptr && deq_state.new_deq_seg) {
727 		xhci_queue_new_dequeue_state(xhci, slot_id, ep_index,
728 				ep->stopped_td->urb->stream_id, &deq_state);
729 		xhci_ring_cmd_db(xhci);
730 	} else {
731 		/* Otherwise ring the doorbell(s) to restart queued transfers */
732 		ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
733 	}
734 
735 	ep->stopped_td = NULL;
736 
737 	/*
738 	 * Drop the lock and complete the URBs in the cancelled TD list.
739 	 * New TDs to be cancelled might be added to the end of the list before
740 	 * we can complete all the URBs for the TDs we already unlinked.
741 	 * So stop when we've completed the URB for the last TD we unlinked.
742 	 */
743 	do {
744 		cur_td = list_entry(ep->cancelled_td_list.next,
745 				struct xhci_td, cancelled_td_list);
746 		list_del_init(&cur_td->cancelled_td_list);
747 
748 		/* Clean up the cancelled URB */
749 		/* Doesn't matter what we pass for status, since the core will
750 		 * just overwrite it (because the URB has been unlinked).
751 		 */
752 		ep_ring = xhci_urb_to_transfer_ring(xhci, cur_td->urb);
753 		if (ep_ring && cur_td->bounce_seg)
754 			xhci_unmap_td_bounce_buffer(xhci, ep_ring, cur_td);
755 		xhci_giveback_urb_in_irq(xhci, cur_td, 0);
756 
757 		/* Stop processing the cancelled list if the watchdog timer is
758 		 * running.
759 		 */
760 		if (xhci->xhc_state & XHCI_STATE_DYING)
761 			return;
762 	} while (cur_td != last_unlinked_td);
763 
764 	/* Return to the event handler with xhci->lock re-acquired */
765 }
766 
767 static void xhci_kill_ring_urbs(struct xhci_hcd *xhci, struct xhci_ring *ring)
768 {
769 	struct xhci_td *cur_td;
770 
771 	while (!list_empty(&ring->td_list)) {
772 		cur_td = list_first_entry(&ring->td_list,
773 				struct xhci_td, td_list);
774 		list_del_init(&cur_td->td_list);
775 		if (!list_empty(&cur_td->cancelled_td_list))
776 			list_del_init(&cur_td->cancelled_td_list);
777 
778 		if (cur_td->bounce_seg)
779 			xhci_unmap_td_bounce_buffer(xhci, ring, cur_td);
780 		xhci_giveback_urb_in_irq(xhci, cur_td, -ESHUTDOWN);
781 	}
782 }
783 
784 static void xhci_kill_endpoint_urbs(struct xhci_hcd *xhci,
785 		int slot_id, int ep_index)
786 {
787 	struct xhci_td *cur_td;
788 	struct xhci_virt_ep *ep;
789 	struct xhci_ring *ring;
790 
791 	ep = &xhci->devs[slot_id]->eps[ep_index];
792 	if ((ep->ep_state & EP_HAS_STREAMS) ||
793 			(ep->ep_state & EP_GETTING_NO_STREAMS)) {
794 		int stream_id;
795 
796 		for (stream_id = 0; stream_id < ep->stream_info->num_streams;
797 				stream_id++) {
798 			xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
799 					"Killing URBs for slot ID %u, ep index %u, stream %u",
800 					slot_id, ep_index, stream_id + 1);
801 			xhci_kill_ring_urbs(xhci,
802 					ep->stream_info->stream_rings[stream_id]);
803 		}
804 	} else {
805 		ring = ep->ring;
806 		if (!ring)
807 			return;
808 		xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
809 				"Killing URBs for slot ID %u, ep index %u",
810 				slot_id, ep_index);
811 		xhci_kill_ring_urbs(xhci, ring);
812 	}
813 	while (!list_empty(&ep->cancelled_td_list)) {
814 		cur_td = list_first_entry(&ep->cancelled_td_list,
815 				struct xhci_td, cancelled_td_list);
816 		list_del_init(&cur_td->cancelled_td_list);
817 		xhci_giveback_urb_in_irq(xhci, cur_td, -ESHUTDOWN);
818 	}
819 }
820 
821 /* Watchdog timer function for when a stop endpoint command fails to complete.
822  * In this case, we assume the host controller is broken or dying or dead.  The
823  * host may still be completing some other events, so we have to be careful to
824  * let the event ring handler and the URB dequeueing/enqueueing functions know
825  * through xhci->state.
826  *
827  * The timer may also fire if the host takes a very long time to respond to the
828  * command, and the stop endpoint command completion handler cannot delete the
829  * timer before the timer function is called.  Another endpoint cancellation may
830  * sneak in before the timer function can grab the lock, and that may queue
831  * another stop endpoint command and add the timer back.  So we cannot use a
832  * simple flag to say whether there is a pending stop endpoint command for a
833  * particular endpoint.
834  *
835  * Instead we use a combination of that flag and a counter for the number of
836  * pending stop endpoint commands.  If the timer is the tail end of the last
837  * stop endpoint command, and the endpoint's command is still pending, we assume
838  * the host is dying.
839  */
840 void xhci_stop_endpoint_command_watchdog(unsigned long arg)
841 {
842 	struct xhci_hcd *xhci;
843 	struct xhci_virt_ep *ep;
844 	int ret, i, j;
845 	unsigned long flags;
846 
847 	ep = (struct xhci_virt_ep *) arg;
848 	xhci = ep->xhci;
849 
850 	spin_lock_irqsave(&xhci->lock, flags);
851 
852 	ep->stop_cmds_pending--;
853 	if (xhci->xhc_state & XHCI_STATE_REMOVING) {
854 		spin_unlock_irqrestore(&xhci->lock, flags);
855 		return;
856 	}
857 	if (xhci->xhc_state & XHCI_STATE_DYING) {
858 		xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
859 				"Stop EP timer ran, but another timer marked "
860 				"xHCI as DYING, exiting.");
861 		spin_unlock_irqrestore(&xhci->lock, flags);
862 		return;
863 	}
864 	if (!(ep->stop_cmds_pending == 0 && (ep->ep_state & EP_HALT_PENDING))) {
865 		xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
866 				"Stop EP timer ran, but no command pending, "
867 				"exiting.");
868 		spin_unlock_irqrestore(&xhci->lock, flags);
869 		return;
870 	}
871 
872 	xhci_warn(xhci, "xHCI host not responding to stop endpoint command.\n");
873 	xhci_warn(xhci, "Assuming host is dying, halting host.\n");
874 	/* Oops, HC is dead or dying or at least not responding to the stop
875 	 * endpoint command.
876 	 */
877 	xhci->xhc_state |= XHCI_STATE_DYING;
878 	/* Disable interrupts from the host controller and start halting it */
879 	xhci_quiesce(xhci);
880 	spin_unlock_irqrestore(&xhci->lock, flags);
881 
882 	ret = xhci_halt(xhci);
883 
884 	spin_lock_irqsave(&xhci->lock, flags);
885 	if (ret < 0) {
886 		/* This is bad; the host is not responding to commands and it's
887 		 * not allowing itself to be halted.  At least interrupts are
888 		 * disabled. If we call usb_hc_died(), it will attempt to
889 		 * disconnect all device drivers under this host.  Those
890 		 * disconnect() methods will wait for all URBs to be unlinked,
891 		 * so we must complete them.
892 		 */
893 		xhci_warn(xhci, "Non-responsive xHCI host is not halting.\n");
894 		xhci_warn(xhci, "Completing active URBs anyway.\n");
895 		/* We could turn all TDs on the rings to no-ops.  This won't
896 		 * help if the host has cached part of the ring, and is slow if
897 		 * we want to preserve the cycle bit.  Skip it and hope the host
898 		 * doesn't touch the memory.
899 		 */
900 	}
901 	for (i = 0; i < MAX_HC_SLOTS; i++) {
902 		if (!xhci->devs[i])
903 			continue;
904 		for (j = 0; j < 31; j++)
905 			xhci_kill_endpoint_urbs(xhci, i, j);
906 	}
907 	spin_unlock_irqrestore(&xhci->lock, flags);
908 	xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
909 			"Calling usb_hc_died()");
910 	usb_hc_died(xhci_to_hcd(xhci));
911 	xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
912 			"xHCI host controller is dead.");
913 }
914 
915 
916 static void update_ring_for_set_deq_completion(struct xhci_hcd *xhci,
917 		struct xhci_virt_device *dev,
918 		struct xhci_ring *ep_ring,
919 		unsigned int ep_index)
920 {
921 	union xhci_trb *dequeue_temp;
922 	int num_trbs_free_temp;
923 	bool revert = false;
924 
925 	num_trbs_free_temp = ep_ring->num_trbs_free;
926 	dequeue_temp = ep_ring->dequeue;
927 
928 	/* If we get two back-to-back stalls, and the first stalled transfer
929 	 * ends just before a link TRB, the dequeue pointer will be left on
930 	 * the link TRB by the code in the while loop.  So we have to update
931 	 * the dequeue pointer one segment further, or we'll jump off
932 	 * the segment into la-la-land.
933 	 */
934 	if (trb_is_link(ep_ring->dequeue)) {
935 		ep_ring->deq_seg = ep_ring->deq_seg->next;
936 		ep_ring->dequeue = ep_ring->deq_seg->trbs;
937 	}
938 
939 	while (ep_ring->dequeue != dev->eps[ep_index].queued_deq_ptr) {
940 		/* We have more usable TRBs */
941 		ep_ring->num_trbs_free++;
942 		ep_ring->dequeue++;
943 		if (trb_is_link(ep_ring->dequeue)) {
944 			if (ep_ring->dequeue ==
945 					dev->eps[ep_index].queued_deq_ptr)
946 				break;
947 			ep_ring->deq_seg = ep_ring->deq_seg->next;
948 			ep_ring->dequeue = ep_ring->deq_seg->trbs;
949 		}
950 		if (ep_ring->dequeue == dequeue_temp) {
951 			revert = true;
952 			break;
953 		}
954 	}
955 
956 	if (revert) {
957 		xhci_dbg(xhci, "Unable to find new dequeue pointer\n");
958 		ep_ring->num_trbs_free = num_trbs_free_temp;
959 	}
960 }
961 
962 /*
963  * When we get a completion for a Set Transfer Ring Dequeue Pointer command,
964  * we need to clear the set deq pending flag in the endpoint ring state, so that
965  * the TD queueing code can ring the doorbell again.  We also need to ring the
966  * endpoint doorbell to restart the ring, but only if there aren't more
967  * cancellations pending.
968  */
969 static void xhci_handle_cmd_set_deq(struct xhci_hcd *xhci, int slot_id,
970 		union xhci_trb *trb, u32 cmd_comp_code)
971 {
972 	unsigned int ep_index;
973 	unsigned int stream_id;
974 	struct xhci_ring *ep_ring;
975 	struct xhci_virt_device *dev;
976 	struct xhci_virt_ep *ep;
977 	struct xhci_ep_ctx *ep_ctx;
978 	struct xhci_slot_ctx *slot_ctx;
979 
980 	ep_index = TRB_TO_EP_INDEX(le32_to_cpu(trb->generic.field[3]));
981 	stream_id = TRB_TO_STREAM_ID(le32_to_cpu(trb->generic.field[2]));
982 	dev = xhci->devs[slot_id];
983 	ep = &dev->eps[ep_index];
984 
985 	ep_ring = xhci_stream_id_to_ring(dev, ep_index, stream_id);
986 	if (!ep_ring) {
987 		xhci_warn(xhci, "WARN Set TR deq ptr command for freed stream ID %u\n",
988 				stream_id);
989 		/* XXX: Harmless??? */
990 		goto cleanup;
991 	}
992 
993 	ep_ctx = xhci_get_ep_ctx(xhci, dev->out_ctx, ep_index);
994 	slot_ctx = xhci_get_slot_ctx(xhci, dev->out_ctx);
995 
996 	if (cmd_comp_code != COMP_SUCCESS) {
997 		unsigned int ep_state;
998 		unsigned int slot_state;
999 
1000 		switch (cmd_comp_code) {
1001 		case COMP_TRB_ERR:
1002 			xhci_warn(xhci, "WARN Set TR Deq Ptr cmd invalid because of stream ID configuration\n");
1003 			break;
1004 		case COMP_CTX_STATE:
1005 			xhci_warn(xhci, "WARN Set TR Deq Ptr cmd failed due to incorrect slot or ep state.\n");
1006 			ep_state = le32_to_cpu(ep_ctx->ep_info);
1007 			ep_state &= EP_STATE_MASK;
1008 			slot_state = le32_to_cpu(slot_ctx->dev_state);
1009 			slot_state = GET_SLOT_STATE(slot_state);
1010 			xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
1011 					"Slot state = %u, EP state = %u",
1012 					slot_state, ep_state);
1013 			break;
1014 		case COMP_EBADSLT:
1015 			xhci_warn(xhci, "WARN Set TR Deq Ptr cmd failed because slot %u was not enabled.\n",
1016 					slot_id);
1017 			break;
1018 		default:
1019 			xhci_warn(xhci, "WARN Set TR Deq Ptr cmd with unknown completion code of %u.\n",
1020 					cmd_comp_code);
1021 			break;
1022 		}
1023 		/* OK what do we do now?  The endpoint state is hosed, and we
1024 		 * should never get to this point if the synchronization between
1025 		 * queueing, and endpoint state are correct.  This might happen
1026 		 * if the device gets disconnected after we've finished
1027 		 * cancelling URBs, which might not be an error...
1028 		 */
1029 	} else {
1030 		u64 deq;
1031 		/* 4.6.10 deq ptr is written to the stream ctx for streams */
1032 		if (ep->ep_state & EP_HAS_STREAMS) {
1033 			struct xhci_stream_ctx *ctx =
1034 				&ep->stream_info->stream_ctx_array[stream_id];
1035 			deq = le64_to_cpu(ctx->stream_ring) & SCTX_DEQ_MASK;
1036 		} else {
1037 			deq = le64_to_cpu(ep_ctx->deq) & ~EP_CTX_CYCLE_MASK;
1038 		}
1039 		xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
1040 			"Successful Set TR Deq Ptr cmd, deq = @%08llx", deq);
1041 		if (xhci_trb_virt_to_dma(ep->queued_deq_seg,
1042 					 ep->queued_deq_ptr) == deq) {
1043 			/* Update the ring's dequeue segment and dequeue pointer
1044 			 * to reflect the new position.
1045 			 */
1046 			update_ring_for_set_deq_completion(xhci, dev,
1047 				ep_ring, ep_index);
1048 		} else {
1049 			xhci_warn(xhci, "Mismatch between completed Set TR Deq Ptr command & xHCI internal state.\n");
1050 			xhci_warn(xhci, "ep deq seg = %p, deq ptr = %p\n",
1051 				  ep->queued_deq_seg, ep->queued_deq_ptr);
1052 		}
1053 	}
1054 
1055 cleanup:
1056 	dev->eps[ep_index].ep_state &= ~SET_DEQ_PENDING;
1057 	dev->eps[ep_index].queued_deq_seg = NULL;
1058 	dev->eps[ep_index].queued_deq_ptr = NULL;
1059 	/* Restart any rings with pending URBs */
1060 	ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
1061 }
1062 
1063 static void xhci_handle_cmd_reset_ep(struct xhci_hcd *xhci, int slot_id,
1064 		union xhci_trb *trb, u32 cmd_comp_code)
1065 {
1066 	unsigned int ep_index;
1067 
1068 	ep_index = TRB_TO_EP_INDEX(le32_to_cpu(trb->generic.field[3]));
1069 	/* This command will only fail if the endpoint wasn't halted,
1070 	 * but we don't care.
1071 	 */
1072 	xhci_dbg_trace(xhci, trace_xhci_dbg_reset_ep,
1073 		"Ignoring reset ep completion code of %u", cmd_comp_code);
1074 
1075 	/* HW with the reset endpoint quirk needs to have a configure endpoint
1076 	 * command complete before the endpoint can be used.  Queue that here
1077 	 * because the HW can't handle two commands being queued in a row.
1078 	 */
1079 	if (xhci->quirks & XHCI_RESET_EP_QUIRK) {
1080 		struct xhci_command *command;
1081 		command = xhci_alloc_command(xhci, false, false, GFP_ATOMIC);
1082 		if (!command) {
1083 			xhci_warn(xhci, "WARN Cannot submit cfg ep: ENOMEM\n");
1084 			return;
1085 		}
1086 		xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
1087 				"Queueing configure endpoint command");
1088 		xhci_queue_configure_endpoint(xhci, command,
1089 				xhci->devs[slot_id]->in_ctx->dma, slot_id,
1090 				false);
1091 		xhci_ring_cmd_db(xhci);
1092 	} else {
1093 		/* Clear our internal halted state */
1094 		xhci->devs[slot_id]->eps[ep_index].ep_state &= ~EP_HALTED;
1095 	}
1096 }
1097 
1098 static void xhci_handle_cmd_enable_slot(struct xhci_hcd *xhci, int slot_id,
1099 		u32 cmd_comp_code)
1100 {
1101 	if (cmd_comp_code == COMP_SUCCESS)
1102 		xhci->slot_id = slot_id;
1103 	else
1104 		xhci->slot_id = 0;
1105 }
1106 
1107 static void xhci_handle_cmd_disable_slot(struct xhci_hcd *xhci, int slot_id)
1108 {
1109 	struct xhci_virt_device *virt_dev;
1110 
1111 	virt_dev = xhci->devs[slot_id];
1112 	if (!virt_dev)
1113 		return;
1114 	if (xhci->quirks & XHCI_EP_LIMIT_QUIRK)
1115 		/* Delete default control endpoint resources */
1116 		xhci_free_device_endpoint_resources(xhci, virt_dev, true);
1117 	xhci_free_virt_device(xhci, slot_id);
1118 }
1119 
1120 static void xhci_handle_cmd_config_ep(struct xhci_hcd *xhci, int slot_id,
1121 		struct xhci_event_cmd *event, u32 cmd_comp_code)
1122 {
1123 	struct xhci_virt_device *virt_dev;
1124 	struct xhci_input_control_ctx *ctrl_ctx;
1125 	unsigned int ep_index;
1126 	unsigned int ep_state;
1127 	u32 add_flags, drop_flags;
1128 
1129 	/*
1130 	 * Configure endpoint commands can come from the USB core
1131 	 * configuration or alt setting changes, or because the HW
1132 	 * needed an extra configure endpoint command after a reset
1133 	 * endpoint command or streams were being configured.
1134 	 * If the command was for a halted endpoint, the xHCI driver
1135 	 * is not waiting on the configure endpoint command.
1136 	 */
1137 	virt_dev = xhci->devs[slot_id];
1138 	ctrl_ctx = xhci_get_input_control_ctx(virt_dev->in_ctx);
1139 	if (!ctrl_ctx) {
1140 		xhci_warn(xhci, "Could not get input context, bad type.\n");
1141 		return;
1142 	}
1143 
1144 	add_flags = le32_to_cpu(ctrl_ctx->add_flags);
1145 	drop_flags = le32_to_cpu(ctrl_ctx->drop_flags);
1146 	/* Input ctx add_flags are the endpoint index plus one */
1147 	ep_index = xhci_last_valid_endpoint(add_flags) - 1;
1148 
1149 	/* A usb_set_interface() call directly after clearing a halted
1150 	 * condition may race on this quirky hardware.  Not worth
1151 	 * worrying about, since this is prototype hardware.  Not sure
1152 	 * if this will work for streams, but streams support was
1153 	 * untested on this prototype.
1154 	 */
1155 	if (xhci->quirks & XHCI_RESET_EP_QUIRK &&
1156 			ep_index != (unsigned int) -1 &&
1157 			add_flags - SLOT_FLAG == drop_flags) {
1158 		ep_state = virt_dev->eps[ep_index].ep_state;
1159 		if (!(ep_state & EP_HALTED))
1160 			return;
1161 		xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
1162 				"Completed config ep cmd - "
1163 				"last ep index = %d, state = %d",
1164 				ep_index, ep_state);
1165 		/* Clear internal halted state and restart ring(s) */
1166 		virt_dev->eps[ep_index].ep_state &= ~EP_HALTED;
1167 		ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
1168 		return;
1169 	}
1170 	return;
1171 }
1172 
1173 static void xhci_handle_cmd_reset_dev(struct xhci_hcd *xhci, int slot_id,
1174 		struct xhci_event_cmd *event)
1175 {
1176 	xhci_dbg(xhci, "Completed reset device command.\n");
1177 	if (!xhci->devs[slot_id])
1178 		xhci_warn(xhci, "Reset device command completion "
1179 				"for disabled slot %u\n", slot_id);
1180 }
1181 
1182 static void xhci_handle_cmd_nec_get_fw(struct xhci_hcd *xhci,
1183 		struct xhci_event_cmd *event)
1184 {
1185 	if (!(xhci->quirks & XHCI_NEC_HOST)) {
1186 		xhci->error_bitmask |= 1 << 6;
1187 		return;
1188 	}
1189 	xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
1190 			"NEC firmware version %2x.%02x",
1191 			NEC_FW_MAJOR(le32_to_cpu(event->status)),
1192 			NEC_FW_MINOR(le32_to_cpu(event->status)));
1193 }
1194 
1195 static void xhci_complete_del_and_free_cmd(struct xhci_command *cmd, u32 status)
1196 {
1197 	list_del(&cmd->cmd_list);
1198 
1199 	if (cmd->completion) {
1200 		cmd->status = status;
1201 		complete(cmd->completion);
1202 	} else {
1203 		kfree(cmd);
1204 	}
1205 }
1206 
1207 void xhci_cleanup_command_queue(struct xhci_hcd *xhci)
1208 {
1209 	struct xhci_command *cur_cmd, *tmp_cmd;
1210 	list_for_each_entry_safe(cur_cmd, tmp_cmd, &xhci->cmd_list, cmd_list)
1211 		xhci_complete_del_and_free_cmd(cur_cmd, COMP_CMD_ABORT);
1212 }
1213 
1214 /*
1215  * Turn all commands on command ring with status set to "aborted" to no-op trbs.
1216  * If there are other commands waiting then restart the ring and kick the timer.
1217  * This must be called with command ring stopped and xhci->lock held.
1218  */
1219 static void xhci_handle_stopped_cmd_ring(struct xhci_hcd *xhci,
1220 					 struct xhci_command *cur_cmd)
1221 {
1222 	struct xhci_command *i_cmd, *tmp_cmd;
1223 	u32 cycle_state;
1224 
1225 	/* Turn all aborted commands in list to no-ops, then restart */
1226 	list_for_each_entry_safe(i_cmd, tmp_cmd, &xhci->cmd_list,
1227 				 cmd_list) {
1228 
1229 		if (i_cmd->status != COMP_CMD_ABORT)
1230 			continue;
1231 
1232 		i_cmd->status = COMP_CMD_STOP;
1233 
1234 		xhci_dbg(xhci, "Turn aborted command %p to no-op\n",
1235 			 i_cmd->command_trb);
1236 		/* get cycle state from the original cmd trb */
1237 		cycle_state = le32_to_cpu(
1238 			i_cmd->command_trb->generic.field[3]) &	TRB_CYCLE;
1239 		/* modify the command trb to no-op command */
1240 		i_cmd->command_trb->generic.field[0] = 0;
1241 		i_cmd->command_trb->generic.field[1] = 0;
1242 		i_cmd->command_trb->generic.field[2] = 0;
1243 		i_cmd->command_trb->generic.field[3] = cpu_to_le32(
1244 			TRB_TYPE(TRB_CMD_NOOP) | cycle_state);
1245 
1246 		/*
1247 		 * caller waiting for completion is called when command
1248 		 *  completion event is received for these no-op commands
1249 		 */
1250 	}
1251 
1252 	xhci->cmd_ring_state = CMD_RING_STATE_RUNNING;
1253 
1254 	/* ring command ring doorbell to restart the command ring */
1255 	if ((xhci->cmd_ring->dequeue != xhci->cmd_ring->enqueue) &&
1256 	    !(xhci->xhc_state & XHCI_STATE_DYING)) {
1257 		xhci->current_cmd = cur_cmd;
1258 		mod_timer(&xhci->cmd_timer, jiffies + XHCI_CMD_DEFAULT_TIMEOUT);
1259 		xhci_ring_cmd_db(xhci);
1260 	}
1261 	return;
1262 }
1263 
1264 
1265 void xhci_handle_command_timeout(unsigned long data)
1266 {
1267 	struct xhci_hcd *xhci;
1268 	int ret;
1269 	unsigned long flags;
1270 	u64 hw_ring_state;
1271 	bool second_timeout = false;
1272 	xhci = (struct xhci_hcd *) data;
1273 
1274 	/* mark this command to be cancelled */
1275 	spin_lock_irqsave(&xhci->lock, flags);
1276 	if (xhci->current_cmd) {
1277 		if (xhci->current_cmd->status == COMP_CMD_ABORT)
1278 			second_timeout = true;
1279 		xhci->current_cmd->status = COMP_CMD_ABORT;
1280 	}
1281 
1282 	/* Make sure command ring is running before aborting it */
1283 	hw_ring_state = xhci_read_64(xhci, &xhci->op_regs->cmd_ring);
1284 	if ((xhci->cmd_ring_state & CMD_RING_STATE_RUNNING) &&
1285 	    (hw_ring_state & CMD_RING_RUNNING))  {
1286 		spin_unlock_irqrestore(&xhci->lock, flags);
1287 		xhci_dbg(xhci, "Command timeout\n");
1288 		ret = xhci_abort_cmd_ring(xhci);
1289 		if (unlikely(ret == -ESHUTDOWN)) {
1290 			xhci_err(xhci, "Abort command ring failed\n");
1291 			xhci_cleanup_command_queue(xhci);
1292 			usb_hc_died(xhci_to_hcd(xhci)->primary_hcd);
1293 			xhci_dbg(xhci, "xHCI host controller is dead.\n");
1294 		}
1295 		return;
1296 	}
1297 
1298 	/* command ring failed to restart, or host removed. Bail out */
1299 	if (second_timeout || xhci->xhc_state & XHCI_STATE_REMOVING) {
1300 		spin_unlock_irqrestore(&xhci->lock, flags);
1301 		xhci_dbg(xhci, "command timed out twice, ring start fail?\n");
1302 		xhci_cleanup_command_queue(xhci);
1303 		return;
1304 	}
1305 
1306 	/* command timeout on stopped ring, ring can't be aborted */
1307 	xhci_dbg(xhci, "Command timeout on stopped ring\n");
1308 	xhci_handle_stopped_cmd_ring(xhci, xhci->current_cmd);
1309 	spin_unlock_irqrestore(&xhci->lock, flags);
1310 	return;
1311 }
1312 
1313 static void handle_cmd_completion(struct xhci_hcd *xhci,
1314 		struct xhci_event_cmd *event)
1315 {
1316 	int slot_id = TRB_TO_SLOT_ID(le32_to_cpu(event->flags));
1317 	u64 cmd_dma;
1318 	dma_addr_t cmd_dequeue_dma;
1319 	u32 cmd_comp_code;
1320 	union xhci_trb *cmd_trb;
1321 	struct xhci_command *cmd;
1322 	u32 cmd_type;
1323 
1324 	cmd_dma = le64_to_cpu(event->cmd_trb);
1325 	cmd_trb = xhci->cmd_ring->dequeue;
1326 	cmd_dequeue_dma = xhci_trb_virt_to_dma(xhci->cmd_ring->deq_seg,
1327 			cmd_trb);
1328 	/* Is the command ring deq ptr out of sync with the deq seg ptr? */
1329 	if (cmd_dequeue_dma == 0) {
1330 		xhci->error_bitmask |= 1 << 4;
1331 		return;
1332 	}
1333 	/* Does the DMA address match our internal dequeue pointer address? */
1334 	if (cmd_dma != (u64) cmd_dequeue_dma) {
1335 		xhci->error_bitmask |= 1 << 5;
1336 		return;
1337 	}
1338 
1339 	cmd = list_entry(xhci->cmd_list.next, struct xhci_command, cmd_list);
1340 
1341 	del_timer(&xhci->cmd_timer);
1342 
1343 	trace_xhci_cmd_completion(cmd_trb, (struct xhci_generic_trb *) event);
1344 
1345 	cmd_comp_code = GET_COMP_CODE(le32_to_cpu(event->status));
1346 
1347 	/* If CMD ring stopped we own the trbs between enqueue and dequeue */
1348 	if (cmd_comp_code == COMP_CMD_STOP) {
1349 		xhci_handle_stopped_cmd_ring(xhci, cmd);
1350 		return;
1351 	}
1352 
1353 	if (cmd->command_trb != xhci->cmd_ring->dequeue) {
1354 		xhci_err(xhci,
1355 			 "Command completion event does not match command\n");
1356 		return;
1357 	}
1358 
1359 	/*
1360 	 * Host aborted the command ring, check if the current command was
1361 	 * supposed to be aborted, otherwise continue normally.
1362 	 * The command ring is stopped now, but the xHC will issue a Command
1363 	 * Ring Stopped event which will cause us to restart it.
1364 	 */
1365 	if (cmd_comp_code == COMP_CMD_ABORT) {
1366 		xhci->cmd_ring_state = CMD_RING_STATE_STOPPED;
1367 		if (cmd->status == COMP_CMD_ABORT)
1368 			goto event_handled;
1369 	}
1370 
1371 	cmd_type = TRB_FIELD_TO_TYPE(le32_to_cpu(cmd_trb->generic.field[3]));
1372 	switch (cmd_type) {
1373 	case TRB_ENABLE_SLOT:
1374 		xhci_handle_cmd_enable_slot(xhci, slot_id, cmd_comp_code);
1375 		break;
1376 	case TRB_DISABLE_SLOT:
1377 		xhci_handle_cmd_disable_slot(xhci, slot_id);
1378 		break;
1379 	case TRB_CONFIG_EP:
1380 		if (!cmd->completion)
1381 			xhci_handle_cmd_config_ep(xhci, slot_id, event,
1382 						  cmd_comp_code);
1383 		break;
1384 	case TRB_EVAL_CONTEXT:
1385 		break;
1386 	case TRB_ADDR_DEV:
1387 		break;
1388 	case TRB_STOP_RING:
1389 		WARN_ON(slot_id != TRB_TO_SLOT_ID(
1390 				le32_to_cpu(cmd_trb->generic.field[3])));
1391 		xhci_handle_cmd_stop_ep(xhci, slot_id, cmd_trb, event);
1392 		break;
1393 	case TRB_SET_DEQ:
1394 		WARN_ON(slot_id != TRB_TO_SLOT_ID(
1395 				le32_to_cpu(cmd_trb->generic.field[3])));
1396 		xhci_handle_cmd_set_deq(xhci, slot_id, cmd_trb, cmd_comp_code);
1397 		break;
1398 	case TRB_CMD_NOOP:
1399 		/* Is this an aborted command turned to NO-OP? */
1400 		if (cmd->status == COMP_CMD_STOP)
1401 			cmd_comp_code = COMP_CMD_STOP;
1402 		break;
1403 	case TRB_RESET_EP:
1404 		WARN_ON(slot_id != TRB_TO_SLOT_ID(
1405 				le32_to_cpu(cmd_trb->generic.field[3])));
1406 		xhci_handle_cmd_reset_ep(xhci, slot_id, cmd_trb, cmd_comp_code);
1407 		break;
1408 	case TRB_RESET_DEV:
1409 		/* SLOT_ID field in reset device cmd completion event TRB is 0.
1410 		 * Use the SLOT_ID from the command TRB instead (xhci 4.6.11)
1411 		 */
1412 		slot_id = TRB_TO_SLOT_ID(
1413 				le32_to_cpu(cmd_trb->generic.field[3]));
1414 		xhci_handle_cmd_reset_dev(xhci, slot_id, event);
1415 		break;
1416 	case TRB_NEC_GET_FW:
1417 		xhci_handle_cmd_nec_get_fw(xhci, event);
1418 		break;
1419 	default:
1420 		/* Skip over unknown commands on the event ring */
1421 		xhci->error_bitmask |= 1 << 6;
1422 		break;
1423 	}
1424 
1425 	/* restart timer if this wasn't the last command */
1426 	if (cmd->cmd_list.next != &xhci->cmd_list) {
1427 		xhci->current_cmd = list_entry(cmd->cmd_list.next,
1428 					       struct xhci_command, cmd_list);
1429 		mod_timer(&xhci->cmd_timer, jiffies + XHCI_CMD_DEFAULT_TIMEOUT);
1430 	}
1431 
1432 event_handled:
1433 	xhci_complete_del_and_free_cmd(cmd, cmd_comp_code);
1434 
1435 	inc_deq(xhci, xhci->cmd_ring);
1436 }
1437 
1438 static void handle_vendor_event(struct xhci_hcd *xhci,
1439 		union xhci_trb *event)
1440 {
1441 	u32 trb_type;
1442 
1443 	trb_type = TRB_FIELD_TO_TYPE(le32_to_cpu(event->generic.field[3]));
1444 	xhci_dbg(xhci, "Vendor specific event TRB type = %u\n", trb_type);
1445 	if (trb_type == TRB_NEC_CMD_COMP && (xhci->quirks & XHCI_NEC_HOST))
1446 		handle_cmd_completion(xhci, &event->event_cmd);
1447 }
1448 
1449 /* @port_id: the one-based port ID from the hardware (indexed from array of all
1450  * port registers -- USB 3.0 and USB 2.0).
1451  *
1452  * Returns a zero-based port number, which is suitable for indexing into each of
1453  * the split roothubs' port arrays and bus state arrays.
1454  * Add one to it in order to call xhci_find_slot_id_by_port.
1455  */
1456 static unsigned int find_faked_portnum_from_hw_portnum(struct usb_hcd *hcd,
1457 		struct xhci_hcd *xhci, u32 port_id)
1458 {
1459 	unsigned int i;
1460 	unsigned int num_similar_speed_ports = 0;
1461 
1462 	/* port_id from the hardware is 1-based, but port_array[], usb3_ports[],
1463 	 * and usb2_ports are 0-based indexes.  Count the number of similar
1464 	 * speed ports, up to 1 port before this port.
1465 	 */
1466 	for (i = 0; i < (port_id - 1); i++) {
1467 		u8 port_speed = xhci->port_array[i];
1468 
1469 		/*
1470 		 * Skip ports that don't have known speeds, or have duplicate
1471 		 * Extended Capabilities port speed entries.
1472 		 */
1473 		if (port_speed == 0 || port_speed == DUPLICATE_ENTRY)
1474 			continue;
1475 
1476 		/*
1477 		 * USB 3.0 ports are always under a USB 3.0 hub.  USB 2.0 and
1478 		 * 1.1 ports are under the USB 2.0 hub.  If the port speed
1479 		 * matches the device speed, it's a similar speed port.
1480 		 */
1481 		if ((port_speed == 0x03) == (hcd->speed >= HCD_USB3))
1482 			num_similar_speed_ports++;
1483 	}
1484 	return num_similar_speed_ports;
1485 }
1486 
1487 static void handle_device_notification(struct xhci_hcd *xhci,
1488 		union xhci_trb *event)
1489 {
1490 	u32 slot_id;
1491 	struct usb_device *udev;
1492 
1493 	slot_id = TRB_TO_SLOT_ID(le32_to_cpu(event->generic.field[3]));
1494 	if (!xhci->devs[slot_id]) {
1495 		xhci_warn(xhci, "Device Notification event for "
1496 				"unused slot %u\n", slot_id);
1497 		return;
1498 	}
1499 
1500 	xhci_dbg(xhci, "Device Wake Notification event for slot ID %u\n",
1501 			slot_id);
1502 	udev = xhci->devs[slot_id]->udev;
1503 	if (udev && udev->parent)
1504 		usb_wakeup_notification(udev->parent, udev->portnum);
1505 }
1506 
1507 static void handle_port_status(struct xhci_hcd *xhci,
1508 		union xhci_trb *event)
1509 {
1510 	struct usb_hcd *hcd;
1511 	u32 port_id;
1512 	u32 temp, temp1;
1513 	int max_ports;
1514 	int slot_id;
1515 	unsigned int faked_port_index;
1516 	u8 major_revision;
1517 	struct xhci_bus_state *bus_state;
1518 	__le32 __iomem **port_array;
1519 	bool bogus_port_status = false;
1520 
1521 	/* Port status change events always have a successful completion code */
1522 	if (GET_COMP_CODE(le32_to_cpu(event->generic.field[2])) != COMP_SUCCESS) {
1523 		xhci_warn(xhci, "WARN: xHC returned failed port status event\n");
1524 		xhci->error_bitmask |= 1 << 8;
1525 	}
1526 	port_id = GET_PORT_ID(le32_to_cpu(event->generic.field[0]));
1527 	xhci_dbg(xhci, "Port Status Change Event for port %d\n", port_id);
1528 
1529 	max_ports = HCS_MAX_PORTS(xhci->hcs_params1);
1530 	if ((port_id <= 0) || (port_id > max_ports)) {
1531 		xhci_warn(xhci, "Invalid port id %d\n", port_id);
1532 		inc_deq(xhci, xhci->event_ring);
1533 		return;
1534 	}
1535 
1536 	/* Figure out which usb_hcd this port is attached to:
1537 	 * is it a USB 3.0 port or a USB 2.0/1.1 port?
1538 	 */
1539 	major_revision = xhci->port_array[port_id - 1];
1540 
1541 	/* Find the right roothub. */
1542 	hcd = xhci_to_hcd(xhci);
1543 	if ((major_revision == 0x03) != (hcd->speed >= HCD_USB3))
1544 		hcd = xhci->shared_hcd;
1545 
1546 	if (major_revision == 0) {
1547 		xhci_warn(xhci, "Event for port %u not in "
1548 				"Extended Capabilities, ignoring.\n",
1549 				port_id);
1550 		bogus_port_status = true;
1551 		goto cleanup;
1552 	}
1553 	if (major_revision == DUPLICATE_ENTRY) {
1554 		xhci_warn(xhci, "Event for port %u duplicated in"
1555 				"Extended Capabilities, ignoring.\n",
1556 				port_id);
1557 		bogus_port_status = true;
1558 		goto cleanup;
1559 	}
1560 
1561 	/*
1562 	 * Hardware port IDs reported by a Port Status Change Event include USB
1563 	 * 3.0 and USB 2.0 ports.  We want to check if the port has reported a
1564 	 * resume event, but we first need to translate the hardware port ID
1565 	 * into the index into the ports on the correct split roothub, and the
1566 	 * correct bus_state structure.
1567 	 */
1568 	bus_state = &xhci->bus_state[hcd_index(hcd)];
1569 	if (hcd->speed >= HCD_USB3)
1570 		port_array = xhci->usb3_ports;
1571 	else
1572 		port_array = xhci->usb2_ports;
1573 	/* Find the faked port hub number */
1574 	faked_port_index = find_faked_portnum_from_hw_portnum(hcd, xhci,
1575 			port_id);
1576 
1577 	temp = readl(port_array[faked_port_index]);
1578 	if (hcd->state == HC_STATE_SUSPENDED) {
1579 		xhci_dbg(xhci, "resume root hub\n");
1580 		usb_hcd_resume_root_hub(hcd);
1581 	}
1582 
1583 	if (hcd->speed >= HCD_USB3 && (temp & PORT_PLS_MASK) == XDEV_INACTIVE)
1584 		bus_state->port_remote_wakeup &= ~(1 << faked_port_index);
1585 
1586 	if ((temp & PORT_PLC) && (temp & PORT_PLS_MASK) == XDEV_RESUME) {
1587 		xhci_dbg(xhci, "port resume event for port %d\n", port_id);
1588 
1589 		temp1 = readl(&xhci->op_regs->command);
1590 		if (!(temp1 & CMD_RUN)) {
1591 			xhci_warn(xhci, "xHC is not running.\n");
1592 			goto cleanup;
1593 		}
1594 
1595 		if (DEV_SUPERSPEED_ANY(temp)) {
1596 			xhci_dbg(xhci, "remote wake SS port %d\n", port_id);
1597 			/* Set a flag to say the port signaled remote wakeup,
1598 			 * so we can tell the difference between the end of
1599 			 * device and host initiated resume.
1600 			 */
1601 			bus_state->port_remote_wakeup |= 1 << faked_port_index;
1602 			xhci_test_and_clear_bit(xhci, port_array,
1603 					faked_port_index, PORT_PLC);
1604 			xhci_set_link_state(xhci, port_array, faked_port_index,
1605 						XDEV_U0);
1606 			/* Need to wait until the next link state change
1607 			 * indicates the device is actually in U0.
1608 			 */
1609 			bogus_port_status = true;
1610 			goto cleanup;
1611 		} else if (!test_bit(faked_port_index,
1612 				     &bus_state->resuming_ports)) {
1613 			xhci_dbg(xhci, "resume HS port %d\n", port_id);
1614 			bus_state->resume_done[faked_port_index] = jiffies +
1615 				msecs_to_jiffies(USB_RESUME_TIMEOUT);
1616 			set_bit(faked_port_index, &bus_state->resuming_ports);
1617 			mod_timer(&hcd->rh_timer,
1618 				  bus_state->resume_done[faked_port_index]);
1619 			/* Do the rest in GetPortStatus */
1620 		}
1621 	}
1622 
1623 	if ((temp & PORT_PLC) && (temp & PORT_PLS_MASK) == XDEV_U0 &&
1624 			DEV_SUPERSPEED_ANY(temp)) {
1625 		xhci_dbg(xhci, "resume SS port %d finished\n", port_id);
1626 		/* We've just brought the device into U0 through either the
1627 		 * Resume state after a device remote wakeup, or through the
1628 		 * U3Exit state after a host-initiated resume.  If it's a device
1629 		 * initiated remote wake, don't pass up the link state change,
1630 		 * so the roothub behavior is consistent with external
1631 		 * USB 3.0 hub behavior.
1632 		 */
1633 		slot_id = xhci_find_slot_id_by_port(hcd, xhci,
1634 				faked_port_index + 1);
1635 		if (slot_id && xhci->devs[slot_id])
1636 			xhci_ring_device(xhci, slot_id);
1637 		if (bus_state->port_remote_wakeup & (1 << faked_port_index)) {
1638 			bus_state->port_remote_wakeup &=
1639 				~(1 << faked_port_index);
1640 			xhci_test_and_clear_bit(xhci, port_array,
1641 					faked_port_index, PORT_PLC);
1642 			usb_wakeup_notification(hcd->self.root_hub,
1643 					faked_port_index + 1);
1644 			bogus_port_status = true;
1645 			goto cleanup;
1646 		}
1647 	}
1648 
1649 	/*
1650 	 * Check to see if xhci-hub.c is waiting on RExit to U0 transition (or
1651 	 * RExit to a disconnect state).  If so, let the the driver know it's
1652 	 * out of the RExit state.
1653 	 */
1654 	if (!DEV_SUPERSPEED_ANY(temp) &&
1655 			test_and_clear_bit(faked_port_index,
1656 				&bus_state->rexit_ports)) {
1657 		complete(&bus_state->rexit_done[faked_port_index]);
1658 		bogus_port_status = true;
1659 		goto cleanup;
1660 	}
1661 
1662 	if (hcd->speed < HCD_USB3)
1663 		xhci_test_and_clear_bit(xhci, port_array, faked_port_index,
1664 					PORT_PLC);
1665 
1666 cleanup:
1667 	/* Update event ring dequeue pointer before dropping the lock */
1668 	inc_deq(xhci, xhci->event_ring);
1669 
1670 	/* Don't make the USB core poll the roothub if we got a bad port status
1671 	 * change event.  Besides, at that point we can't tell which roothub
1672 	 * (USB 2.0 or USB 3.0) to kick.
1673 	 */
1674 	if (bogus_port_status)
1675 		return;
1676 
1677 	/*
1678 	 * xHCI port-status-change events occur when the "or" of all the
1679 	 * status-change bits in the portsc register changes from 0 to 1.
1680 	 * New status changes won't cause an event if any other change
1681 	 * bits are still set.  When an event occurs, switch over to
1682 	 * polling to avoid losing status changes.
1683 	 */
1684 	xhci_dbg(xhci, "%s: starting port polling.\n", __func__);
1685 	set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
1686 	spin_unlock(&xhci->lock);
1687 	/* Pass this up to the core */
1688 	usb_hcd_poll_rh_status(hcd);
1689 	spin_lock(&xhci->lock);
1690 }
1691 
1692 /*
1693  * This TD is defined by the TRBs starting at start_trb in start_seg and ending
1694  * at end_trb, which may be in another segment.  If the suspect DMA address is a
1695  * TRB in this TD, this function returns that TRB's segment.  Otherwise it
1696  * returns 0.
1697  */
1698 struct xhci_segment *trb_in_td(struct xhci_hcd *xhci,
1699 		struct xhci_segment *start_seg,
1700 		union xhci_trb	*start_trb,
1701 		union xhci_trb	*end_trb,
1702 		dma_addr_t	suspect_dma,
1703 		bool		debug)
1704 {
1705 	dma_addr_t start_dma;
1706 	dma_addr_t end_seg_dma;
1707 	dma_addr_t end_trb_dma;
1708 	struct xhci_segment *cur_seg;
1709 
1710 	start_dma = xhci_trb_virt_to_dma(start_seg, start_trb);
1711 	cur_seg = start_seg;
1712 
1713 	do {
1714 		if (start_dma == 0)
1715 			return NULL;
1716 		/* We may get an event for a Link TRB in the middle of a TD */
1717 		end_seg_dma = xhci_trb_virt_to_dma(cur_seg,
1718 				&cur_seg->trbs[TRBS_PER_SEGMENT - 1]);
1719 		/* If the end TRB isn't in this segment, this is set to 0 */
1720 		end_trb_dma = xhci_trb_virt_to_dma(cur_seg, end_trb);
1721 
1722 		if (debug)
1723 			xhci_warn(xhci,
1724 				"Looking for event-dma %016llx trb-start %016llx trb-end %016llx seg-start %016llx seg-end %016llx\n",
1725 				(unsigned long long)suspect_dma,
1726 				(unsigned long long)start_dma,
1727 				(unsigned long long)end_trb_dma,
1728 				(unsigned long long)cur_seg->dma,
1729 				(unsigned long long)end_seg_dma);
1730 
1731 		if (end_trb_dma > 0) {
1732 			/* The end TRB is in this segment, so suspect should be here */
1733 			if (start_dma <= end_trb_dma) {
1734 				if (suspect_dma >= start_dma && suspect_dma <= end_trb_dma)
1735 					return cur_seg;
1736 			} else {
1737 				/* Case for one segment with
1738 				 * a TD wrapped around to the top
1739 				 */
1740 				if ((suspect_dma >= start_dma &&
1741 							suspect_dma <= end_seg_dma) ||
1742 						(suspect_dma >= cur_seg->dma &&
1743 						 suspect_dma <= end_trb_dma))
1744 					return cur_seg;
1745 			}
1746 			return NULL;
1747 		} else {
1748 			/* Might still be somewhere in this segment */
1749 			if (suspect_dma >= start_dma && suspect_dma <= end_seg_dma)
1750 				return cur_seg;
1751 		}
1752 		cur_seg = cur_seg->next;
1753 		start_dma = xhci_trb_virt_to_dma(cur_seg, &cur_seg->trbs[0]);
1754 	} while (cur_seg != start_seg);
1755 
1756 	return NULL;
1757 }
1758 
1759 static void xhci_cleanup_halted_endpoint(struct xhci_hcd *xhci,
1760 		unsigned int slot_id, unsigned int ep_index,
1761 		unsigned int stream_id,
1762 		struct xhci_td *td, union xhci_trb *event_trb)
1763 {
1764 	struct xhci_virt_ep *ep = &xhci->devs[slot_id]->eps[ep_index];
1765 	struct xhci_command *command;
1766 	command = xhci_alloc_command(xhci, false, false, GFP_ATOMIC);
1767 	if (!command)
1768 		return;
1769 
1770 	ep->ep_state |= EP_HALTED;
1771 	ep->stopped_stream = stream_id;
1772 
1773 	xhci_queue_reset_ep(xhci, command, slot_id, ep_index);
1774 	xhci_cleanup_stalled_ring(xhci, ep_index, td);
1775 
1776 	ep->stopped_stream = 0;
1777 
1778 	xhci_ring_cmd_db(xhci);
1779 }
1780 
1781 /* Check if an error has halted the endpoint ring.  The class driver will
1782  * cleanup the halt for a non-default control endpoint if we indicate a stall.
1783  * However, a babble and other errors also halt the endpoint ring, and the class
1784  * driver won't clear the halt in that case, so we need to issue a Set Transfer
1785  * Ring Dequeue Pointer command manually.
1786  */
1787 static int xhci_requires_manual_halt_cleanup(struct xhci_hcd *xhci,
1788 		struct xhci_ep_ctx *ep_ctx,
1789 		unsigned int trb_comp_code)
1790 {
1791 	/* TRB completion codes that may require a manual halt cleanup */
1792 	if (trb_comp_code == COMP_TX_ERR ||
1793 			trb_comp_code == COMP_BABBLE ||
1794 			trb_comp_code == COMP_SPLIT_ERR)
1795 		/* The 0.95 spec says a babbling control endpoint
1796 		 * is not halted. The 0.96 spec says it is.  Some HW
1797 		 * claims to be 0.95 compliant, but it halts the control
1798 		 * endpoint anyway.  Check if a babble halted the
1799 		 * endpoint.
1800 		 */
1801 		if ((ep_ctx->ep_info & cpu_to_le32(EP_STATE_MASK)) ==
1802 		    cpu_to_le32(EP_STATE_HALTED))
1803 			return 1;
1804 
1805 	return 0;
1806 }
1807 
1808 int xhci_is_vendor_info_code(struct xhci_hcd *xhci, unsigned int trb_comp_code)
1809 {
1810 	if (trb_comp_code >= 224 && trb_comp_code <= 255) {
1811 		/* Vendor defined "informational" completion code,
1812 		 * treat as not-an-error.
1813 		 */
1814 		xhci_dbg(xhci, "Vendor defined info completion code %u\n",
1815 				trb_comp_code);
1816 		xhci_dbg(xhci, "Treating code as success.\n");
1817 		return 1;
1818 	}
1819 	return 0;
1820 }
1821 
1822 /*
1823  * Finish the td processing, remove the td from td list;
1824  * Return 1 if the urb can be given back.
1825  */
1826 static int finish_td(struct xhci_hcd *xhci, struct xhci_td *td,
1827 	union xhci_trb *event_trb, struct xhci_transfer_event *event,
1828 	struct xhci_virt_ep *ep, int *status, bool skip)
1829 {
1830 	struct xhci_virt_device *xdev;
1831 	struct xhci_ring *ep_ring;
1832 	unsigned int slot_id;
1833 	int ep_index;
1834 	struct urb *urb = NULL;
1835 	struct xhci_ep_ctx *ep_ctx;
1836 	int ret = 0;
1837 	struct urb_priv	*urb_priv;
1838 	u32 trb_comp_code;
1839 
1840 	slot_id = TRB_TO_SLOT_ID(le32_to_cpu(event->flags));
1841 	xdev = xhci->devs[slot_id];
1842 	ep_index = TRB_TO_EP_ID(le32_to_cpu(event->flags)) - 1;
1843 	ep_ring = xhci_dma_to_transfer_ring(ep, le64_to_cpu(event->buffer));
1844 	ep_ctx = xhci_get_ep_ctx(xhci, xdev->out_ctx, ep_index);
1845 	trb_comp_code = GET_COMP_CODE(le32_to_cpu(event->transfer_len));
1846 
1847 	if (skip)
1848 		goto td_cleanup;
1849 
1850 	if (trb_comp_code == COMP_STOP_INVAL ||
1851 			trb_comp_code == COMP_STOP ||
1852 			trb_comp_code == COMP_STOP_SHORT) {
1853 		/* The Endpoint Stop Command completion will take care of any
1854 		 * stopped TDs.  A stopped TD may be restarted, so don't update
1855 		 * the ring dequeue pointer or take this TD off any lists yet.
1856 		 */
1857 		ep->stopped_td = td;
1858 		return 0;
1859 	}
1860 	if (trb_comp_code == COMP_STALL ||
1861 		xhci_requires_manual_halt_cleanup(xhci, ep_ctx,
1862 						trb_comp_code)) {
1863 		/* Issue a reset endpoint command to clear the host side
1864 		 * halt, followed by a set dequeue command to move the
1865 		 * dequeue pointer past the TD.
1866 		 * The class driver clears the device side halt later.
1867 		 */
1868 		xhci_cleanup_halted_endpoint(xhci, slot_id, ep_index,
1869 					ep_ring->stream_id, td, event_trb);
1870 	} else {
1871 		/* Update ring dequeue pointer */
1872 		while (ep_ring->dequeue != td->last_trb)
1873 			inc_deq(xhci, ep_ring);
1874 		inc_deq(xhci, ep_ring);
1875 	}
1876 
1877 td_cleanup:
1878 	/* Clean up the endpoint's TD list */
1879 	urb = td->urb;
1880 	urb_priv = urb->hcpriv;
1881 
1882 	/* if a bounce buffer was used to align this td then unmap it */
1883 	if (td->bounce_seg)
1884 		xhci_unmap_td_bounce_buffer(xhci, ep_ring, td);
1885 
1886 	/* Do one last check of the actual transfer length.
1887 	 * If the host controller said we transferred more data than the buffer
1888 	 * length, urb->actual_length will be a very big number (since it's
1889 	 * unsigned).  Play it safe and say we didn't transfer anything.
1890 	 */
1891 	if (urb->actual_length > urb->transfer_buffer_length) {
1892 		xhci_warn(xhci, "URB transfer length is wrong, xHC issue? req. len = %u, act. len = %u\n",
1893 			urb->transfer_buffer_length,
1894 			urb->actual_length);
1895 		urb->actual_length = 0;
1896 		if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
1897 			*status = -EREMOTEIO;
1898 		else
1899 			*status = 0;
1900 	}
1901 	list_del_init(&td->td_list);
1902 	/* Was this TD slated to be cancelled but completed anyway? */
1903 	if (!list_empty(&td->cancelled_td_list))
1904 		list_del_init(&td->cancelled_td_list);
1905 
1906 	urb_priv->td_cnt++;
1907 	/* Giveback the urb when all the tds are completed */
1908 	if (urb_priv->td_cnt == urb_priv->length) {
1909 		ret = 1;
1910 		if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
1911 			xhci_to_hcd(xhci)->self.bandwidth_isoc_reqs--;
1912 			if (xhci_to_hcd(xhci)->self.bandwidth_isoc_reqs == 0) {
1913 				if (xhci->quirks & XHCI_AMD_PLL_FIX)
1914 					usb_amd_quirk_pll_enable();
1915 			}
1916 		}
1917 	}
1918 
1919 	return ret;
1920 }
1921 
1922 /*
1923  * Process control tds, update urb status and actual_length.
1924  */
1925 static int process_ctrl_td(struct xhci_hcd *xhci, struct xhci_td *td,
1926 	union xhci_trb *event_trb, struct xhci_transfer_event *event,
1927 	struct xhci_virt_ep *ep, int *status)
1928 {
1929 	struct xhci_virt_device *xdev;
1930 	struct xhci_ring *ep_ring;
1931 	unsigned int slot_id;
1932 	int ep_index;
1933 	struct xhci_ep_ctx *ep_ctx;
1934 	u32 trb_comp_code;
1935 
1936 	slot_id = TRB_TO_SLOT_ID(le32_to_cpu(event->flags));
1937 	xdev = xhci->devs[slot_id];
1938 	ep_index = TRB_TO_EP_ID(le32_to_cpu(event->flags)) - 1;
1939 	ep_ring = xhci_dma_to_transfer_ring(ep, le64_to_cpu(event->buffer));
1940 	ep_ctx = xhci_get_ep_ctx(xhci, xdev->out_ctx, ep_index);
1941 	trb_comp_code = GET_COMP_CODE(le32_to_cpu(event->transfer_len));
1942 
1943 	switch (trb_comp_code) {
1944 	case COMP_SUCCESS:
1945 		if (event_trb == ep_ring->dequeue) {
1946 			xhci_warn(xhci, "WARN: Success on ctrl setup TRB "
1947 					"without IOC set??\n");
1948 			*status = -ESHUTDOWN;
1949 		} else if (event_trb != td->last_trb) {
1950 			xhci_warn(xhci, "WARN: Success on ctrl data TRB "
1951 					"without IOC set??\n");
1952 			*status = -ESHUTDOWN;
1953 		} else {
1954 			*status = 0;
1955 		}
1956 		break;
1957 	case COMP_SHORT_TX:
1958 		if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
1959 			*status = -EREMOTEIO;
1960 		else
1961 			*status = 0;
1962 		break;
1963 	case COMP_STOP_SHORT:
1964 		if (event_trb == ep_ring->dequeue || event_trb == td->last_trb)
1965 			xhci_warn(xhci, "WARN: Stopped Short Packet on ctrl setup or status TRB\n");
1966 		else
1967 			td->urb->actual_length =
1968 				EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
1969 
1970 		return finish_td(xhci, td, event_trb, event, ep, status, false);
1971 	case COMP_STOP:
1972 		/* Did we stop at data stage? */
1973 		if (event_trb != ep_ring->dequeue && event_trb != td->last_trb)
1974 			td->urb->actual_length =
1975 				td->urb->transfer_buffer_length -
1976 				EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
1977 		/* fall through */
1978 	case COMP_STOP_INVAL:
1979 		return finish_td(xhci, td, event_trb, event, ep, status, false);
1980 	default:
1981 		if (!xhci_requires_manual_halt_cleanup(xhci,
1982 					ep_ctx, trb_comp_code))
1983 			break;
1984 		xhci_dbg(xhci, "TRB error code %u, "
1985 				"halted endpoint index = %u\n",
1986 				trb_comp_code, ep_index);
1987 		/* else fall through */
1988 	case COMP_STALL:
1989 		/* Did we transfer part of the data (middle) phase? */
1990 		if (event_trb != ep_ring->dequeue &&
1991 				event_trb != td->last_trb)
1992 			td->urb->actual_length =
1993 				td->urb->transfer_buffer_length -
1994 				EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
1995 		else if (!td->urb_length_set)
1996 			td->urb->actual_length = 0;
1997 
1998 		return finish_td(xhci, td, event_trb, event, ep, status, false);
1999 	}
2000 	/*
2001 	 * Did we transfer any data, despite the errors that might have
2002 	 * happened?  I.e. did we get past the setup stage?
2003 	 */
2004 	if (event_trb != ep_ring->dequeue) {
2005 		/* The event was for the status stage */
2006 		if (event_trb == td->last_trb) {
2007 			if (td->urb_length_set) {
2008 				/* Don't overwrite a previously set error code
2009 				 */
2010 				if ((*status == -EINPROGRESS || *status == 0) &&
2011 						(td->urb->transfer_flags
2012 						 & URB_SHORT_NOT_OK))
2013 					/* Did we already see a short data
2014 					 * stage? */
2015 					*status = -EREMOTEIO;
2016 			} else {
2017 				td->urb->actual_length =
2018 					td->urb->transfer_buffer_length;
2019 			}
2020 		} else {
2021 			/*
2022 			 * Maybe the event was for the data stage? If so, update
2023 			 * already the actual_length of the URB and flag it as
2024 			 * set, so that it is not overwritten in the event for
2025 			 * the last TRB.
2026 			 */
2027 			td->urb_length_set = true;
2028 			td->urb->actual_length =
2029 				td->urb->transfer_buffer_length -
2030 				EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
2031 			xhci_dbg(xhci, "Waiting for status "
2032 					"stage event\n");
2033 			return 0;
2034 		}
2035 	}
2036 
2037 	return finish_td(xhci, td, event_trb, event, ep, status, false);
2038 }
2039 
2040 /*
2041  * Process isochronous tds, update urb packet status and actual_length.
2042  */
2043 static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
2044 	union xhci_trb *event_trb, struct xhci_transfer_event *event,
2045 	struct xhci_virt_ep *ep, int *status)
2046 {
2047 	struct xhci_ring *ep_ring;
2048 	struct urb_priv *urb_priv;
2049 	int idx;
2050 	int len = 0;
2051 	union xhci_trb *cur_trb;
2052 	struct xhci_segment *cur_seg;
2053 	struct usb_iso_packet_descriptor *frame;
2054 	u32 trb_comp_code;
2055 	bool skip_td = false;
2056 
2057 	ep_ring = xhci_dma_to_transfer_ring(ep, le64_to_cpu(event->buffer));
2058 	trb_comp_code = GET_COMP_CODE(le32_to_cpu(event->transfer_len));
2059 	urb_priv = td->urb->hcpriv;
2060 	idx = urb_priv->td_cnt;
2061 	frame = &td->urb->iso_frame_desc[idx];
2062 
2063 	/* handle completion code */
2064 	switch (trb_comp_code) {
2065 	case COMP_SUCCESS:
2066 		if (EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)) == 0) {
2067 			frame->status = 0;
2068 			break;
2069 		}
2070 		if ((xhci->quirks & XHCI_TRUST_TX_LENGTH))
2071 			trb_comp_code = COMP_SHORT_TX;
2072 	/* fallthrough */
2073 	case COMP_STOP_SHORT:
2074 	case COMP_SHORT_TX:
2075 		frame->status = td->urb->transfer_flags & URB_SHORT_NOT_OK ?
2076 				-EREMOTEIO : 0;
2077 		break;
2078 	case COMP_BW_OVER:
2079 		frame->status = -ECOMM;
2080 		skip_td = true;
2081 		break;
2082 	case COMP_BUFF_OVER:
2083 	case COMP_BABBLE:
2084 		frame->status = -EOVERFLOW;
2085 		skip_td = true;
2086 		break;
2087 	case COMP_DEV_ERR:
2088 	case COMP_STALL:
2089 		frame->status = -EPROTO;
2090 		skip_td = true;
2091 		break;
2092 	case COMP_TX_ERR:
2093 		frame->status = -EPROTO;
2094 		if (event_trb != td->last_trb)
2095 			return 0;
2096 		skip_td = true;
2097 		break;
2098 	case COMP_STOP:
2099 	case COMP_STOP_INVAL:
2100 		break;
2101 	default:
2102 		frame->status = -1;
2103 		break;
2104 	}
2105 
2106 	if (trb_comp_code == COMP_SUCCESS || skip_td) {
2107 		frame->actual_length = frame->length;
2108 		td->urb->actual_length += frame->length;
2109 	} else if (trb_comp_code == COMP_STOP_SHORT) {
2110 		frame->actual_length =
2111 			EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
2112 		td->urb->actual_length += frame->actual_length;
2113 	} else {
2114 		for (cur_trb = ep_ring->dequeue,
2115 		     cur_seg = ep_ring->deq_seg; cur_trb != event_trb;
2116 		     next_trb(xhci, ep_ring, &cur_seg, &cur_trb)) {
2117 			if (!TRB_TYPE_NOOP_LE32(cur_trb->generic.field[3]) &&
2118 			    !TRB_TYPE_LINK_LE32(cur_trb->generic.field[3]))
2119 				len += TRB_LEN(le32_to_cpu(cur_trb->generic.field[2]));
2120 		}
2121 		len += TRB_LEN(le32_to_cpu(cur_trb->generic.field[2])) -
2122 			EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
2123 
2124 		if (trb_comp_code != COMP_STOP_INVAL) {
2125 			frame->actual_length = len;
2126 			td->urb->actual_length += len;
2127 		}
2128 	}
2129 
2130 	return finish_td(xhci, td, event_trb, event, ep, status, false);
2131 }
2132 
2133 static int skip_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
2134 			struct xhci_transfer_event *event,
2135 			struct xhci_virt_ep *ep, int *status)
2136 {
2137 	struct xhci_ring *ep_ring;
2138 	struct urb_priv *urb_priv;
2139 	struct usb_iso_packet_descriptor *frame;
2140 	int idx;
2141 
2142 	ep_ring = xhci_dma_to_transfer_ring(ep, le64_to_cpu(event->buffer));
2143 	urb_priv = td->urb->hcpriv;
2144 	idx = urb_priv->td_cnt;
2145 	frame = &td->urb->iso_frame_desc[idx];
2146 
2147 	/* The transfer is partly done. */
2148 	frame->status = -EXDEV;
2149 
2150 	/* calc actual length */
2151 	frame->actual_length = 0;
2152 
2153 	/* Update ring dequeue pointer */
2154 	while (ep_ring->dequeue != td->last_trb)
2155 		inc_deq(xhci, ep_ring);
2156 	inc_deq(xhci, ep_ring);
2157 
2158 	return finish_td(xhci, td, NULL, event, ep, status, true);
2159 }
2160 
2161 /*
2162  * Process bulk and interrupt tds, update urb status and actual_length.
2163  */
2164 static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td,
2165 	union xhci_trb *event_trb, struct xhci_transfer_event *event,
2166 	struct xhci_virt_ep *ep, int *status)
2167 {
2168 	struct xhci_ring *ep_ring;
2169 	union xhci_trb *cur_trb;
2170 	struct xhci_segment *cur_seg;
2171 	u32 trb_comp_code;
2172 
2173 	ep_ring = xhci_dma_to_transfer_ring(ep, le64_to_cpu(event->buffer));
2174 	trb_comp_code = GET_COMP_CODE(le32_to_cpu(event->transfer_len));
2175 
2176 	switch (trb_comp_code) {
2177 	case COMP_SUCCESS:
2178 		/* Double check that the HW transferred everything. */
2179 		if (event_trb != td->last_trb ||
2180 		    EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)) != 0) {
2181 			xhci_warn(xhci, "WARN Successful completion "
2182 					"on short TX\n");
2183 			if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
2184 				*status = -EREMOTEIO;
2185 			else
2186 				*status = 0;
2187 			if ((xhci->quirks & XHCI_TRUST_TX_LENGTH))
2188 				trb_comp_code = COMP_SHORT_TX;
2189 		} else {
2190 			*status = 0;
2191 		}
2192 		break;
2193 	case COMP_STOP_SHORT:
2194 	case COMP_SHORT_TX:
2195 		if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
2196 			*status = -EREMOTEIO;
2197 		else
2198 			*status = 0;
2199 		break;
2200 	default:
2201 		/* Others already handled above */
2202 		break;
2203 	}
2204 	if (trb_comp_code == COMP_SHORT_TX)
2205 		xhci_dbg(xhci, "ep %#x - asked for %d bytes, "
2206 				"%d bytes untransferred\n",
2207 				td->urb->ep->desc.bEndpointAddress,
2208 				td->urb->transfer_buffer_length,
2209 				EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)));
2210 	/* Stopped - short packet completion */
2211 	if (trb_comp_code == COMP_STOP_SHORT) {
2212 		td->urb->actual_length =
2213 			EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
2214 
2215 		if (td->urb->transfer_buffer_length <
2216 				td->urb->actual_length) {
2217 			xhci_warn(xhci, "HC gave bad length of %d bytes txed\n",
2218 				EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)));
2219 			td->urb->actual_length = 0;
2220 			 /* status will be set by usb core for canceled urbs */
2221 		}
2222 	/* Fast path - was this the last TRB in the TD for this URB? */
2223 	} else if (event_trb == td->last_trb) {
2224 		if (EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)) != 0) {
2225 			td->urb->actual_length =
2226 				td->urb->transfer_buffer_length -
2227 				EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
2228 			if (td->urb->transfer_buffer_length <
2229 					td->urb->actual_length) {
2230 				xhci_warn(xhci, "HC gave bad length "
2231 						"of %d bytes left\n",
2232 					  EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)));
2233 				td->urb->actual_length = 0;
2234 				if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
2235 					*status = -EREMOTEIO;
2236 				else
2237 					*status = 0;
2238 			}
2239 			/* Don't overwrite a previously set error code */
2240 			if (*status == -EINPROGRESS) {
2241 				if (td->urb->transfer_flags & URB_SHORT_NOT_OK)
2242 					*status = -EREMOTEIO;
2243 				else
2244 					*status = 0;
2245 			}
2246 		} else {
2247 			td->urb->actual_length =
2248 				td->urb->transfer_buffer_length;
2249 			/* Ignore a short packet completion if the
2250 			 * untransferred length was zero.
2251 			 */
2252 			if (*status == -EREMOTEIO)
2253 				*status = 0;
2254 		}
2255 	} else {
2256 		/* Slow path - walk the list, starting from the dequeue
2257 		 * pointer, to get the actual length transferred.
2258 		 */
2259 		td->urb->actual_length = 0;
2260 		for (cur_trb = ep_ring->dequeue, cur_seg = ep_ring->deq_seg;
2261 				cur_trb != event_trb;
2262 				next_trb(xhci, ep_ring, &cur_seg, &cur_trb)) {
2263 			if (!TRB_TYPE_NOOP_LE32(cur_trb->generic.field[3]) &&
2264 			    !TRB_TYPE_LINK_LE32(cur_trb->generic.field[3]))
2265 				td->urb->actual_length +=
2266 					TRB_LEN(le32_to_cpu(cur_trb->generic.field[2]));
2267 		}
2268 		/* If the ring didn't stop on a Link or No-op TRB, add
2269 		 * in the actual bytes transferred from the Normal TRB
2270 		 */
2271 		if (trb_comp_code != COMP_STOP_INVAL)
2272 			td->urb->actual_length +=
2273 				TRB_LEN(le32_to_cpu(cur_trb->generic.field[2])) -
2274 				EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
2275 	}
2276 
2277 	return finish_td(xhci, td, event_trb, event, ep, status, false);
2278 }
2279 
2280 /*
2281  * If this function returns an error condition, it means it got a Transfer
2282  * event with a corrupted Slot ID, Endpoint ID, or TRB DMA address.
2283  * At this point, the host controller is probably hosed and should be reset.
2284  */
2285 static int handle_tx_event(struct xhci_hcd *xhci,
2286 		struct xhci_transfer_event *event)
2287 	__releases(&xhci->lock)
2288 	__acquires(&xhci->lock)
2289 {
2290 	struct xhci_virt_device *xdev;
2291 	struct xhci_virt_ep *ep;
2292 	struct xhci_ring *ep_ring;
2293 	unsigned int slot_id;
2294 	int ep_index;
2295 	struct xhci_td *td = NULL;
2296 	dma_addr_t event_dma;
2297 	struct xhci_segment *event_seg;
2298 	union xhci_trb *event_trb;
2299 	struct urb *urb = NULL;
2300 	int status = -EINPROGRESS;
2301 	struct urb_priv *urb_priv;
2302 	struct xhci_ep_ctx *ep_ctx;
2303 	struct list_head *tmp;
2304 	u32 trb_comp_code;
2305 	int ret = 0;
2306 	int td_num = 0;
2307 	bool handling_skipped_tds = false;
2308 
2309 	slot_id = TRB_TO_SLOT_ID(le32_to_cpu(event->flags));
2310 	xdev = xhci->devs[slot_id];
2311 	if (!xdev) {
2312 		xhci_err(xhci, "ERROR Transfer event pointed to bad slot\n");
2313 		xhci_err(xhci, "@%016llx %08x %08x %08x %08x\n",
2314 			 (unsigned long long) xhci_trb_virt_to_dma(
2315 				 xhci->event_ring->deq_seg,
2316 				 xhci->event_ring->dequeue),
2317 			 lower_32_bits(le64_to_cpu(event->buffer)),
2318 			 upper_32_bits(le64_to_cpu(event->buffer)),
2319 			 le32_to_cpu(event->transfer_len),
2320 			 le32_to_cpu(event->flags));
2321 		xhci_dbg(xhci, "Event ring:\n");
2322 		xhci_debug_segment(xhci, xhci->event_ring->deq_seg);
2323 		return -ENODEV;
2324 	}
2325 
2326 	/* Endpoint ID is 1 based, our index is zero based */
2327 	ep_index = TRB_TO_EP_ID(le32_to_cpu(event->flags)) - 1;
2328 	ep = &xdev->eps[ep_index];
2329 	ep_ring = xhci_dma_to_transfer_ring(ep, le64_to_cpu(event->buffer));
2330 	ep_ctx = xhci_get_ep_ctx(xhci, xdev->out_ctx, ep_index);
2331 	if (!ep_ring ||
2332 	    (le32_to_cpu(ep_ctx->ep_info) & EP_STATE_MASK) ==
2333 	    EP_STATE_DISABLED) {
2334 		xhci_err(xhci, "ERROR Transfer event for disabled endpoint "
2335 				"or incorrect stream ring\n");
2336 		xhci_err(xhci, "@%016llx %08x %08x %08x %08x\n",
2337 			 (unsigned long long) xhci_trb_virt_to_dma(
2338 				 xhci->event_ring->deq_seg,
2339 				 xhci->event_ring->dequeue),
2340 			 lower_32_bits(le64_to_cpu(event->buffer)),
2341 			 upper_32_bits(le64_to_cpu(event->buffer)),
2342 			 le32_to_cpu(event->transfer_len),
2343 			 le32_to_cpu(event->flags));
2344 		xhci_dbg(xhci, "Event ring:\n");
2345 		xhci_debug_segment(xhci, xhci->event_ring->deq_seg);
2346 		return -ENODEV;
2347 	}
2348 
2349 	/* Count current td numbers if ep->skip is set */
2350 	if (ep->skip) {
2351 		list_for_each(tmp, &ep_ring->td_list)
2352 			td_num++;
2353 	}
2354 
2355 	event_dma = le64_to_cpu(event->buffer);
2356 	trb_comp_code = GET_COMP_CODE(le32_to_cpu(event->transfer_len));
2357 	/* Look for common error cases */
2358 	switch (trb_comp_code) {
2359 	/* Skip codes that require special handling depending on
2360 	 * transfer type
2361 	 */
2362 	case COMP_SUCCESS:
2363 		if (EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)) == 0)
2364 			break;
2365 		if (xhci->quirks & XHCI_TRUST_TX_LENGTH)
2366 			trb_comp_code = COMP_SHORT_TX;
2367 		else
2368 			xhci_warn_ratelimited(xhci,
2369 					"WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk?\n");
2370 	case COMP_SHORT_TX:
2371 		break;
2372 	case COMP_STOP:
2373 		xhci_dbg(xhci, "Stopped on Transfer TRB\n");
2374 		break;
2375 	case COMP_STOP_INVAL:
2376 		xhci_dbg(xhci, "Stopped on No-op or Link TRB\n");
2377 		break;
2378 	case COMP_STOP_SHORT:
2379 		xhci_dbg(xhci, "Stopped with short packet transfer detected\n");
2380 		break;
2381 	case COMP_STALL:
2382 		xhci_dbg(xhci, "Stalled endpoint\n");
2383 		ep->ep_state |= EP_HALTED;
2384 		status = -EPIPE;
2385 		break;
2386 	case COMP_TRB_ERR:
2387 		xhci_warn(xhci, "WARN: TRB error on endpoint\n");
2388 		status = -EILSEQ;
2389 		break;
2390 	case COMP_SPLIT_ERR:
2391 	case COMP_TX_ERR:
2392 		xhci_dbg(xhci, "Transfer error on endpoint\n");
2393 		status = -EPROTO;
2394 		break;
2395 	case COMP_BABBLE:
2396 		xhci_dbg(xhci, "Babble error on endpoint\n");
2397 		status = -EOVERFLOW;
2398 		break;
2399 	case COMP_DB_ERR:
2400 		xhci_warn(xhci, "WARN: HC couldn't access mem fast enough\n");
2401 		status = -ENOSR;
2402 		break;
2403 	case COMP_BW_OVER:
2404 		xhci_warn(xhci, "WARN: bandwidth overrun event on endpoint\n");
2405 		break;
2406 	case COMP_BUFF_OVER:
2407 		xhci_warn(xhci, "WARN: buffer overrun event on endpoint\n");
2408 		break;
2409 	case COMP_UNDERRUN:
2410 		/*
2411 		 * When the Isoch ring is empty, the xHC will generate
2412 		 * a Ring Overrun Event for IN Isoch endpoint or Ring
2413 		 * Underrun Event for OUT Isoch endpoint.
2414 		 */
2415 		xhci_dbg(xhci, "underrun event on endpoint\n");
2416 		if (!list_empty(&ep_ring->td_list))
2417 			xhci_dbg(xhci, "Underrun Event for slot %d ep %d "
2418 					"still with TDs queued?\n",
2419 				 TRB_TO_SLOT_ID(le32_to_cpu(event->flags)),
2420 				 ep_index);
2421 		goto cleanup;
2422 	case COMP_OVERRUN:
2423 		xhci_dbg(xhci, "overrun event on endpoint\n");
2424 		if (!list_empty(&ep_ring->td_list))
2425 			xhci_dbg(xhci, "Overrun Event for slot %d ep %d "
2426 					"still with TDs queued?\n",
2427 				 TRB_TO_SLOT_ID(le32_to_cpu(event->flags)),
2428 				 ep_index);
2429 		goto cleanup;
2430 	case COMP_DEV_ERR:
2431 		xhci_warn(xhci, "WARN: detect an incompatible device");
2432 		status = -EPROTO;
2433 		break;
2434 	case COMP_MISSED_INT:
2435 		/*
2436 		 * When encounter missed service error, one or more isoc tds
2437 		 * may be missed by xHC.
2438 		 * Set skip flag of the ep_ring; Complete the missed tds as
2439 		 * short transfer when process the ep_ring next time.
2440 		 */
2441 		ep->skip = true;
2442 		xhci_dbg(xhci, "Miss service interval error, set skip flag\n");
2443 		goto cleanup;
2444 	case COMP_PING_ERR:
2445 		ep->skip = true;
2446 		xhci_dbg(xhci, "No Ping response error, Skip one Isoc TD\n");
2447 		goto cleanup;
2448 	default:
2449 		if (xhci_is_vendor_info_code(xhci, trb_comp_code)) {
2450 			status = 0;
2451 			break;
2452 		}
2453 		xhci_warn(xhci, "ERROR Unknown event condition %u, HC probably busted\n",
2454 			  trb_comp_code);
2455 		goto cleanup;
2456 	}
2457 
2458 	do {
2459 		/* This TRB should be in the TD at the head of this ring's
2460 		 * TD list.
2461 		 */
2462 		if (list_empty(&ep_ring->td_list)) {
2463 			/*
2464 			 * A stopped endpoint may generate an extra completion
2465 			 * event if the device was suspended.  Don't print
2466 			 * warnings.
2467 			 */
2468 			if (!(trb_comp_code == COMP_STOP ||
2469 						trb_comp_code == COMP_STOP_INVAL)) {
2470 				xhci_warn(xhci, "WARN Event TRB for slot %d ep %d with no TDs queued?\n",
2471 						TRB_TO_SLOT_ID(le32_to_cpu(event->flags)),
2472 						ep_index);
2473 				xhci_dbg(xhci, "Event TRB with TRB type ID %u\n",
2474 						(le32_to_cpu(event->flags) &
2475 						 TRB_TYPE_BITMASK)>>10);
2476 				xhci_print_trb_offsets(xhci, (union xhci_trb *) event);
2477 			}
2478 			if (ep->skip) {
2479 				ep->skip = false;
2480 				xhci_dbg(xhci, "td_list is empty while skip "
2481 						"flag set. Clear skip flag.\n");
2482 			}
2483 			ret = 0;
2484 			goto cleanup;
2485 		}
2486 
2487 		/* We've skipped all the TDs on the ep ring when ep->skip set */
2488 		if (ep->skip && td_num == 0) {
2489 			ep->skip = false;
2490 			xhci_dbg(xhci, "All tds on the ep_ring skipped. "
2491 						"Clear skip flag.\n");
2492 			ret = 0;
2493 			goto cleanup;
2494 		}
2495 
2496 		td = list_entry(ep_ring->td_list.next, struct xhci_td, td_list);
2497 		if (ep->skip)
2498 			td_num--;
2499 
2500 		/* Is this a TRB in the currently executing TD? */
2501 		event_seg = trb_in_td(xhci, ep_ring->deq_seg, ep_ring->dequeue,
2502 				td->last_trb, event_dma, false);
2503 
2504 		/*
2505 		 * Skip the Force Stopped Event. The event_trb(event_dma) of FSE
2506 		 * is not in the current TD pointed by ep_ring->dequeue because
2507 		 * that the hardware dequeue pointer still at the previous TRB
2508 		 * of the current TD. The previous TRB maybe a Link TD or the
2509 		 * last TRB of the previous TD. The command completion handle
2510 		 * will take care the rest.
2511 		 */
2512 		if (!event_seg && (trb_comp_code == COMP_STOP ||
2513 				   trb_comp_code == COMP_STOP_INVAL)) {
2514 			ret = 0;
2515 			goto cleanup;
2516 		}
2517 
2518 		if (!event_seg) {
2519 			if (!ep->skip ||
2520 			    !usb_endpoint_xfer_isoc(&td->urb->ep->desc)) {
2521 				/* Some host controllers give a spurious
2522 				 * successful event after a short transfer.
2523 				 * Ignore it.
2524 				 */
2525 				if ((xhci->quirks & XHCI_SPURIOUS_SUCCESS) &&
2526 						ep_ring->last_td_was_short) {
2527 					ep_ring->last_td_was_short = false;
2528 					ret = 0;
2529 					goto cleanup;
2530 				}
2531 				/* HC is busted, give up! */
2532 				xhci_err(xhci,
2533 					"ERROR Transfer event TRB DMA ptr not "
2534 					"part of current TD ep_index %d "
2535 					"comp_code %u\n", ep_index,
2536 					trb_comp_code);
2537 				trb_in_td(xhci, ep_ring->deq_seg,
2538 					  ep_ring->dequeue, td->last_trb,
2539 					  event_dma, true);
2540 				return -ESHUTDOWN;
2541 			}
2542 
2543 			ret = skip_isoc_td(xhci, td, event, ep, &status);
2544 			goto cleanup;
2545 		}
2546 		if (trb_comp_code == COMP_SHORT_TX)
2547 			ep_ring->last_td_was_short = true;
2548 		else
2549 			ep_ring->last_td_was_short = false;
2550 
2551 		if (ep->skip) {
2552 			xhci_dbg(xhci, "Found td. Clear skip flag.\n");
2553 			ep->skip = false;
2554 		}
2555 
2556 		event_trb = &event_seg->trbs[(event_dma - event_seg->dma) /
2557 						sizeof(*event_trb)];
2558 		/*
2559 		 * No-op TRB should not trigger interrupts.
2560 		 * If event_trb is a no-op TRB, it means the
2561 		 * corresponding TD has been cancelled. Just ignore
2562 		 * the TD.
2563 		 */
2564 		if (TRB_TYPE_NOOP_LE32(event_trb->generic.field[3])) {
2565 			xhci_dbg(xhci,
2566 				 "event_trb is a no-op TRB. Skip it\n");
2567 			goto cleanup;
2568 		}
2569 
2570 		/* Now update the urb's actual_length and give back to
2571 		 * the core
2572 		 */
2573 		if (usb_endpoint_xfer_control(&td->urb->ep->desc))
2574 			ret = process_ctrl_td(xhci, td, event_trb, event, ep,
2575 						 &status);
2576 		else if (usb_endpoint_xfer_isoc(&td->urb->ep->desc))
2577 			ret = process_isoc_td(xhci, td, event_trb, event, ep,
2578 						 &status);
2579 		else
2580 			ret = process_bulk_intr_td(xhci, td, event_trb, event,
2581 						 ep, &status);
2582 
2583 cleanup:
2584 
2585 
2586 		handling_skipped_tds = ep->skip &&
2587 			trb_comp_code != COMP_MISSED_INT &&
2588 			trb_comp_code != COMP_PING_ERR;
2589 
2590 		/*
2591 		 * Do not update event ring dequeue pointer if we're in a loop
2592 		 * processing missed tds.
2593 		 */
2594 		if (!handling_skipped_tds)
2595 			inc_deq(xhci, xhci->event_ring);
2596 
2597 		if (ret) {
2598 			urb = td->urb;
2599 			urb_priv = urb->hcpriv;
2600 
2601 			xhci_urb_free_priv(urb_priv);
2602 
2603 			usb_hcd_unlink_urb_from_ep(bus_to_hcd(urb->dev->bus), urb);
2604 			if ((urb->actual_length != urb->transfer_buffer_length &&
2605 						(urb->transfer_flags &
2606 						 URB_SHORT_NOT_OK)) ||
2607 					(status != 0 &&
2608 					 !usb_endpoint_xfer_isoc(&urb->ep->desc)))
2609 				xhci_dbg(xhci, "Giveback URB %p, len = %d, "
2610 						"expected = %d, status = %d\n",
2611 						urb, urb->actual_length,
2612 						urb->transfer_buffer_length,
2613 						status);
2614 			spin_unlock(&xhci->lock);
2615 			/* EHCI, UHCI, and OHCI always unconditionally set the
2616 			 * urb->status of an isochronous endpoint to 0.
2617 			 */
2618 			if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS)
2619 				status = 0;
2620 			usb_hcd_giveback_urb(bus_to_hcd(urb->dev->bus), urb, status);
2621 			spin_lock(&xhci->lock);
2622 		}
2623 
2624 	/*
2625 	 * If ep->skip is set, it means there are missed tds on the
2626 	 * endpoint ring need to take care of.
2627 	 * Process them as short transfer until reach the td pointed by
2628 	 * the event.
2629 	 */
2630 	} while (handling_skipped_tds);
2631 
2632 	return 0;
2633 }
2634 
2635 /*
2636  * This function handles all OS-owned events on the event ring.  It may drop
2637  * xhci->lock between event processing (e.g. to pass up port status changes).
2638  * Returns >0 for "possibly more events to process" (caller should call again),
2639  * otherwise 0 if done.  In future, <0 returns should indicate error code.
2640  */
2641 static int xhci_handle_event(struct xhci_hcd *xhci)
2642 {
2643 	union xhci_trb *event;
2644 	int update_ptrs = 1;
2645 	int ret;
2646 
2647 	if (!xhci->event_ring || !xhci->event_ring->dequeue) {
2648 		xhci->error_bitmask |= 1 << 1;
2649 		return 0;
2650 	}
2651 
2652 	event = xhci->event_ring->dequeue;
2653 	/* Does the HC or OS own the TRB? */
2654 	if ((le32_to_cpu(event->event_cmd.flags) & TRB_CYCLE) !=
2655 	    xhci->event_ring->cycle_state) {
2656 		xhci->error_bitmask |= 1 << 2;
2657 		return 0;
2658 	}
2659 
2660 	/*
2661 	 * Barrier between reading the TRB_CYCLE (valid) flag above and any
2662 	 * speculative reads of the event's flags/data below.
2663 	 */
2664 	rmb();
2665 	/* FIXME: Handle more event types. */
2666 	switch ((le32_to_cpu(event->event_cmd.flags) & TRB_TYPE_BITMASK)) {
2667 	case TRB_TYPE(TRB_COMPLETION):
2668 		handle_cmd_completion(xhci, &event->event_cmd);
2669 		break;
2670 	case TRB_TYPE(TRB_PORT_STATUS):
2671 		handle_port_status(xhci, event);
2672 		update_ptrs = 0;
2673 		break;
2674 	case TRB_TYPE(TRB_TRANSFER):
2675 		ret = handle_tx_event(xhci, &event->trans_event);
2676 		if (ret < 0)
2677 			xhci->error_bitmask |= 1 << 9;
2678 		else
2679 			update_ptrs = 0;
2680 		break;
2681 	case TRB_TYPE(TRB_DEV_NOTE):
2682 		handle_device_notification(xhci, event);
2683 		break;
2684 	default:
2685 		if ((le32_to_cpu(event->event_cmd.flags) & TRB_TYPE_BITMASK) >=
2686 		    TRB_TYPE(48))
2687 			handle_vendor_event(xhci, event);
2688 		else
2689 			xhci->error_bitmask |= 1 << 3;
2690 	}
2691 	/* Any of the above functions may drop and re-acquire the lock, so check
2692 	 * to make sure a watchdog timer didn't mark the host as non-responsive.
2693 	 */
2694 	if (xhci->xhc_state & XHCI_STATE_DYING) {
2695 		xhci_dbg(xhci, "xHCI host dying, returning from "
2696 				"event handler.\n");
2697 		return 0;
2698 	}
2699 
2700 	if (update_ptrs)
2701 		/* Update SW event ring dequeue pointer */
2702 		inc_deq(xhci, xhci->event_ring);
2703 
2704 	/* Are there more items on the event ring?  Caller will call us again to
2705 	 * check.
2706 	 */
2707 	return 1;
2708 }
2709 
2710 /*
2711  * xHCI spec says we can get an interrupt, and if the HC has an error condition,
2712  * we might get bad data out of the event ring.  Section 4.10.2.7 has a list of
2713  * indicators of an event TRB error, but we check the status *first* to be safe.
2714  */
2715 irqreturn_t xhci_irq(struct usb_hcd *hcd)
2716 {
2717 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
2718 	u32 status;
2719 	u64 temp_64;
2720 	union xhci_trb *event_ring_deq;
2721 	dma_addr_t deq;
2722 
2723 	spin_lock(&xhci->lock);
2724 	/* Check if the xHC generated the interrupt, or the irq is shared */
2725 	status = readl(&xhci->op_regs->status);
2726 	if (status == 0xffffffff)
2727 		goto hw_died;
2728 
2729 	if (!(status & STS_EINT)) {
2730 		spin_unlock(&xhci->lock);
2731 		return IRQ_NONE;
2732 	}
2733 	if (status & STS_FATAL) {
2734 		xhci_warn(xhci, "WARNING: Host System Error\n");
2735 		xhci_halt(xhci);
2736 hw_died:
2737 		spin_unlock(&xhci->lock);
2738 		return IRQ_HANDLED;
2739 	}
2740 
2741 	/*
2742 	 * Clear the op reg interrupt status first,
2743 	 * so we can receive interrupts from other MSI-X interrupters.
2744 	 * Write 1 to clear the interrupt status.
2745 	 */
2746 	status |= STS_EINT;
2747 	writel(status, &xhci->op_regs->status);
2748 	/* FIXME when MSI-X is supported and there are multiple vectors */
2749 	/* Clear the MSI-X event interrupt status */
2750 
2751 	if (hcd->irq) {
2752 		u32 irq_pending;
2753 		/* Acknowledge the PCI interrupt */
2754 		irq_pending = readl(&xhci->ir_set->irq_pending);
2755 		irq_pending |= IMAN_IP;
2756 		writel(irq_pending, &xhci->ir_set->irq_pending);
2757 	}
2758 
2759 	if (xhci->xhc_state & XHCI_STATE_DYING ||
2760 	    xhci->xhc_state & XHCI_STATE_HALTED) {
2761 		xhci_dbg(xhci, "xHCI dying, ignoring interrupt. "
2762 				"Shouldn't IRQs be disabled?\n");
2763 		/* Clear the event handler busy flag (RW1C);
2764 		 * the event ring should be empty.
2765 		 */
2766 		temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
2767 		xhci_write_64(xhci, temp_64 | ERST_EHB,
2768 				&xhci->ir_set->erst_dequeue);
2769 		spin_unlock(&xhci->lock);
2770 
2771 		return IRQ_HANDLED;
2772 	}
2773 
2774 	event_ring_deq = xhci->event_ring->dequeue;
2775 	/* FIXME this should be a delayed service routine
2776 	 * that clears the EHB.
2777 	 */
2778 	while (xhci_handle_event(xhci) > 0) {}
2779 
2780 	temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
2781 	/* If necessary, update the HW's version of the event ring deq ptr. */
2782 	if (event_ring_deq != xhci->event_ring->dequeue) {
2783 		deq = xhci_trb_virt_to_dma(xhci->event_ring->deq_seg,
2784 				xhci->event_ring->dequeue);
2785 		if (deq == 0)
2786 			xhci_warn(xhci, "WARN something wrong with SW event "
2787 					"ring dequeue ptr.\n");
2788 		/* Update HC event ring dequeue pointer */
2789 		temp_64 &= ERST_PTR_MASK;
2790 		temp_64 |= ((u64) deq & (u64) ~ERST_PTR_MASK);
2791 	}
2792 
2793 	/* Clear the event handler busy flag (RW1C); event ring is empty. */
2794 	temp_64 |= ERST_EHB;
2795 	xhci_write_64(xhci, temp_64, &xhci->ir_set->erst_dequeue);
2796 
2797 	spin_unlock(&xhci->lock);
2798 
2799 	return IRQ_HANDLED;
2800 }
2801 
2802 irqreturn_t xhci_msi_irq(int irq, void *hcd)
2803 {
2804 	return xhci_irq(hcd);
2805 }
2806 
2807 /****		Endpoint Ring Operations	****/
2808 
2809 /*
2810  * Generic function for queueing a TRB on a ring.
2811  * The caller must have checked to make sure there's room on the ring.
2812  *
2813  * @more_trbs_coming:	Will you enqueue more TRBs before calling
2814  *			prepare_transfer()?
2815  */
2816 static void queue_trb(struct xhci_hcd *xhci, struct xhci_ring *ring,
2817 		bool more_trbs_coming,
2818 		u32 field1, u32 field2, u32 field3, u32 field4)
2819 {
2820 	struct xhci_generic_trb *trb;
2821 
2822 	trb = &ring->enqueue->generic;
2823 	trb->field[0] = cpu_to_le32(field1);
2824 	trb->field[1] = cpu_to_le32(field2);
2825 	trb->field[2] = cpu_to_le32(field3);
2826 	trb->field[3] = cpu_to_le32(field4);
2827 	inc_enq(xhci, ring, more_trbs_coming);
2828 }
2829 
2830 /*
2831  * Does various checks on the endpoint ring, and makes it ready to queue num_trbs.
2832  * FIXME allocate segments if the ring is full.
2833  */
2834 static int prepare_ring(struct xhci_hcd *xhci, struct xhci_ring *ep_ring,
2835 		u32 ep_state, unsigned int num_trbs, gfp_t mem_flags)
2836 {
2837 	unsigned int num_trbs_needed;
2838 
2839 	/* Make sure the endpoint has been added to xHC schedule */
2840 	switch (ep_state) {
2841 	case EP_STATE_DISABLED:
2842 		/*
2843 		 * USB core changed config/interfaces without notifying us,
2844 		 * or hardware is reporting the wrong state.
2845 		 */
2846 		xhci_warn(xhci, "WARN urb submitted to disabled ep\n");
2847 		return -ENOENT;
2848 	case EP_STATE_ERROR:
2849 		xhci_warn(xhci, "WARN waiting for error on ep to be cleared\n");
2850 		/* FIXME event handling code for error needs to clear it */
2851 		/* XXX not sure if this should be -ENOENT or not */
2852 		return -EINVAL;
2853 	case EP_STATE_HALTED:
2854 		xhci_dbg(xhci, "WARN halted endpoint, queueing URB anyway.\n");
2855 	case EP_STATE_STOPPED:
2856 	case EP_STATE_RUNNING:
2857 		break;
2858 	default:
2859 		xhci_err(xhci, "ERROR unknown endpoint state for ep\n");
2860 		/*
2861 		 * FIXME issue Configure Endpoint command to try to get the HC
2862 		 * back into a known state.
2863 		 */
2864 		return -EINVAL;
2865 	}
2866 
2867 	while (1) {
2868 		if (room_on_ring(xhci, ep_ring, num_trbs))
2869 			break;
2870 
2871 		if (ep_ring == xhci->cmd_ring) {
2872 			xhci_err(xhci, "Do not support expand command ring\n");
2873 			return -ENOMEM;
2874 		}
2875 
2876 		xhci_dbg_trace(xhci, trace_xhci_dbg_ring_expansion,
2877 				"ERROR no room on ep ring, try ring expansion");
2878 		num_trbs_needed = num_trbs - ep_ring->num_trbs_free;
2879 		if (xhci_ring_expansion(xhci, ep_ring, num_trbs_needed,
2880 					mem_flags)) {
2881 			xhci_err(xhci, "Ring expansion failed\n");
2882 			return -ENOMEM;
2883 		}
2884 	}
2885 
2886 	while (trb_is_link(ep_ring->enqueue)) {
2887 		/* If we're not dealing with 0.95 hardware or isoc rings
2888 		 * on AMD 0.96 host, clear the chain bit.
2889 		 */
2890 		if (!xhci_link_trb_quirk(xhci) &&
2891 		    !(ep_ring->type == TYPE_ISOC &&
2892 		      (xhci->quirks & XHCI_AMD_0x96_HOST)))
2893 			ep_ring->enqueue->link.control &=
2894 				cpu_to_le32(~TRB_CHAIN);
2895 		else
2896 			ep_ring->enqueue->link.control |=
2897 				cpu_to_le32(TRB_CHAIN);
2898 
2899 		wmb();
2900 		ep_ring->enqueue->link.control ^= cpu_to_le32(TRB_CYCLE);
2901 
2902 		/* Toggle the cycle bit after the last ring segment. */
2903 		if (link_trb_toggles_cycle(ep_ring->enqueue))
2904 			ep_ring->cycle_state ^= 1;
2905 
2906 		ep_ring->enq_seg = ep_ring->enq_seg->next;
2907 		ep_ring->enqueue = ep_ring->enq_seg->trbs;
2908 	}
2909 	return 0;
2910 }
2911 
2912 static int prepare_transfer(struct xhci_hcd *xhci,
2913 		struct xhci_virt_device *xdev,
2914 		unsigned int ep_index,
2915 		unsigned int stream_id,
2916 		unsigned int num_trbs,
2917 		struct urb *urb,
2918 		unsigned int td_index,
2919 		gfp_t mem_flags)
2920 {
2921 	int ret;
2922 	struct urb_priv *urb_priv;
2923 	struct xhci_td	*td;
2924 	struct xhci_ring *ep_ring;
2925 	struct xhci_ep_ctx *ep_ctx = xhci_get_ep_ctx(xhci, xdev->out_ctx, ep_index);
2926 
2927 	ep_ring = xhci_stream_id_to_ring(xdev, ep_index, stream_id);
2928 	if (!ep_ring) {
2929 		xhci_dbg(xhci, "Can't prepare ring for bad stream ID %u\n",
2930 				stream_id);
2931 		return -EINVAL;
2932 	}
2933 
2934 	ret = prepare_ring(xhci, ep_ring,
2935 			   le32_to_cpu(ep_ctx->ep_info) & EP_STATE_MASK,
2936 			   num_trbs, mem_flags);
2937 	if (ret)
2938 		return ret;
2939 
2940 	urb_priv = urb->hcpriv;
2941 	td = urb_priv->td[td_index];
2942 
2943 	INIT_LIST_HEAD(&td->td_list);
2944 	INIT_LIST_HEAD(&td->cancelled_td_list);
2945 
2946 	if (td_index == 0) {
2947 		ret = usb_hcd_link_urb_to_ep(bus_to_hcd(urb->dev->bus), urb);
2948 		if (unlikely(ret))
2949 			return ret;
2950 	}
2951 
2952 	td->urb = urb;
2953 	/* Add this TD to the tail of the endpoint ring's TD list */
2954 	list_add_tail(&td->td_list, &ep_ring->td_list);
2955 	td->start_seg = ep_ring->enq_seg;
2956 	td->first_trb = ep_ring->enqueue;
2957 
2958 	urb_priv->td[td_index] = td;
2959 
2960 	return 0;
2961 }
2962 
2963 static unsigned int count_trbs(u64 addr, u64 len)
2964 {
2965 	unsigned int num_trbs;
2966 
2967 	num_trbs = DIV_ROUND_UP(len + (addr & (TRB_MAX_BUFF_SIZE - 1)),
2968 			TRB_MAX_BUFF_SIZE);
2969 	if (num_trbs == 0)
2970 		num_trbs++;
2971 
2972 	return num_trbs;
2973 }
2974 
2975 static inline unsigned int count_trbs_needed(struct urb *urb)
2976 {
2977 	return count_trbs(urb->transfer_dma, urb->transfer_buffer_length);
2978 }
2979 
2980 static unsigned int count_sg_trbs_needed(struct urb *urb)
2981 {
2982 	struct scatterlist *sg;
2983 	unsigned int i, len, full_len, num_trbs = 0;
2984 
2985 	full_len = urb->transfer_buffer_length;
2986 
2987 	for_each_sg(urb->sg, sg, urb->num_mapped_sgs, i) {
2988 		len = sg_dma_len(sg);
2989 		num_trbs += count_trbs(sg_dma_address(sg), len);
2990 		len = min_t(unsigned int, len, full_len);
2991 		full_len -= len;
2992 		if (full_len == 0)
2993 			break;
2994 	}
2995 
2996 	return num_trbs;
2997 }
2998 
2999 static unsigned int count_isoc_trbs_needed(struct urb *urb, int i)
3000 {
3001 	u64 addr, len;
3002 
3003 	addr = (u64) (urb->transfer_dma + urb->iso_frame_desc[i].offset);
3004 	len = urb->iso_frame_desc[i].length;
3005 
3006 	return count_trbs(addr, len);
3007 }
3008 
3009 static void check_trb_math(struct urb *urb, int running_total)
3010 {
3011 	if (unlikely(running_total != urb->transfer_buffer_length))
3012 		dev_err(&urb->dev->dev, "%s - ep %#x - Miscalculated tx length, "
3013 				"queued %#x (%d), asked for %#x (%d)\n",
3014 				__func__,
3015 				urb->ep->desc.bEndpointAddress,
3016 				running_total, running_total,
3017 				urb->transfer_buffer_length,
3018 				urb->transfer_buffer_length);
3019 }
3020 
3021 static void giveback_first_trb(struct xhci_hcd *xhci, int slot_id,
3022 		unsigned int ep_index, unsigned int stream_id, int start_cycle,
3023 		struct xhci_generic_trb *start_trb)
3024 {
3025 	/*
3026 	 * Pass all the TRBs to the hardware at once and make sure this write
3027 	 * isn't reordered.
3028 	 */
3029 	wmb();
3030 	if (start_cycle)
3031 		start_trb->field[3] |= cpu_to_le32(start_cycle);
3032 	else
3033 		start_trb->field[3] &= cpu_to_le32(~TRB_CYCLE);
3034 	xhci_ring_ep_doorbell(xhci, slot_id, ep_index, stream_id);
3035 }
3036 
3037 static void check_interval(struct xhci_hcd *xhci, struct urb *urb,
3038 						struct xhci_ep_ctx *ep_ctx)
3039 {
3040 	int xhci_interval;
3041 	int ep_interval;
3042 
3043 	xhci_interval = EP_INTERVAL_TO_UFRAMES(le32_to_cpu(ep_ctx->ep_info));
3044 	ep_interval = urb->interval;
3045 
3046 	/* Convert to microframes */
3047 	if (urb->dev->speed == USB_SPEED_LOW ||
3048 			urb->dev->speed == USB_SPEED_FULL)
3049 		ep_interval *= 8;
3050 
3051 	/* FIXME change this to a warning and a suggestion to use the new API
3052 	 * to set the polling interval (once the API is added).
3053 	 */
3054 	if (xhci_interval != ep_interval) {
3055 		dev_dbg_ratelimited(&urb->dev->dev,
3056 				"Driver uses different interval (%d microframe%s) than xHCI (%d microframe%s)\n",
3057 				ep_interval, ep_interval == 1 ? "" : "s",
3058 				xhci_interval, xhci_interval == 1 ? "" : "s");
3059 		urb->interval = xhci_interval;
3060 		/* Convert back to frames for LS/FS devices */
3061 		if (urb->dev->speed == USB_SPEED_LOW ||
3062 				urb->dev->speed == USB_SPEED_FULL)
3063 			urb->interval /= 8;
3064 	}
3065 }
3066 
3067 /*
3068  * xHCI uses normal TRBs for both bulk and interrupt.  When the interrupt
3069  * endpoint is to be serviced, the xHC will consume (at most) one TD.  A TD
3070  * (comprised of sg list entries) can take several service intervals to
3071  * transmit.
3072  */
3073 int xhci_queue_intr_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
3074 		struct urb *urb, int slot_id, unsigned int ep_index)
3075 {
3076 	struct xhci_ep_ctx *ep_ctx;
3077 
3078 	ep_ctx = xhci_get_ep_ctx(xhci, xhci->devs[slot_id]->out_ctx, ep_index);
3079 	check_interval(xhci, urb, ep_ctx);
3080 
3081 	return xhci_queue_bulk_tx(xhci, mem_flags, urb, slot_id, ep_index);
3082 }
3083 
3084 /*
3085  * For xHCI 1.0 host controllers, TD size is the number of max packet sized
3086  * packets remaining in the TD (*not* including this TRB).
3087  *
3088  * Total TD packet count = total_packet_count =
3089  *     DIV_ROUND_UP(TD size in bytes / wMaxPacketSize)
3090  *
3091  * Packets transferred up to and including this TRB = packets_transferred =
3092  *     rounddown(total bytes transferred including this TRB / wMaxPacketSize)
3093  *
3094  * TD size = total_packet_count - packets_transferred
3095  *
3096  * For xHCI 0.96 and older, TD size field should be the remaining bytes
3097  * including this TRB, right shifted by 10
3098  *
3099  * For all hosts it must fit in bits 21:17, so it can't be bigger than 31.
3100  * This is taken care of in the TRB_TD_SIZE() macro
3101  *
3102  * The last TRB in a TD must have the TD size set to zero.
3103  */
3104 static u32 xhci_td_remainder(struct xhci_hcd *xhci, int transferred,
3105 			      int trb_buff_len, unsigned int td_total_len,
3106 			      struct urb *urb, bool more_trbs_coming)
3107 {
3108 	u32 maxp, total_packet_count;
3109 
3110 	/* MTK xHCI is mostly 0.97 but contains some features from 1.0 */
3111 	if (xhci->hci_version < 0x100 && !(xhci->quirks & XHCI_MTK_HOST))
3112 		return ((td_total_len - transferred) >> 10);
3113 
3114 	/* One TRB with a zero-length data packet. */
3115 	if (!more_trbs_coming || (transferred == 0 && trb_buff_len == 0) ||
3116 	    trb_buff_len == td_total_len)
3117 		return 0;
3118 
3119 	/* for MTK xHCI, TD size doesn't include this TRB */
3120 	if (xhci->quirks & XHCI_MTK_HOST)
3121 		trb_buff_len = 0;
3122 
3123 	maxp = GET_MAX_PACKET(usb_endpoint_maxp(&urb->ep->desc));
3124 	total_packet_count = DIV_ROUND_UP(td_total_len, maxp);
3125 
3126 	/* Queueing functions don't count the current TRB into transferred */
3127 	return (total_packet_count - ((transferred + trb_buff_len) / maxp));
3128 }
3129 
3130 
3131 static int xhci_align_td(struct xhci_hcd *xhci, struct urb *urb, u32 enqd_len,
3132 			 u32 *trb_buff_len, struct xhci_segment *seg)
3133 {
3134 	struct device *dev = xhci_to_hcd(xhci)->self.controller;
3135 	unsigned int unalign;
3136 	unsigned int max_pkt;
3137 	u32 new_buff_len;
3138 
3139 	max_pkt = GET_MAX_PACKET(usb_endpoint_maxp(&urb->ep->desc));
3140 	unalign = (enqd_len + *trb_buff_len) % max_pkt;
3141 
3142 	/* we got lucky, last normal TRB data on segment is packet aligned */
3143 	if (unalign == 0)
3144 		return 0;
3145 
3146 	xhci_dbg(xhci, "Unaligned %d bytes, buff len %d\n",
3147 		 unalign, *trb_buff_len);
3148 
3149 	/* is the last nornal TRB alignable by splitting it */
3150 	if (*trb_buff_len > unalign) {
3151 		*trb_buff_len -= unalign;
3152 		xhci_dbg(xhci, "split align, new buff len %d\n", *trb_buff_len);
3153 		return 0;
3154 	}
3155 
3156 	/*
3157 	 * We want enqd_len + trb_buff_len to sum up to a number aligned to
3158 	 * number which is divisible by the endpoint's wMaxPacketSize. IOW:
3159 	 * (size of currently enqueued TRBs + remainder) % wMaxPacketSize == 0.
3160 	 */
3161 	new_buff_len = max_pkt - (enqd_len % max_pkt);
3162 
3163 	if (new_buff_len > (urb->transfer_buffer_length - enqd_len))
3164 		new_buff_len = (urb->transfer_buffer_length - enqd_len);
3165 
3166 	/* create a max max_pkt sized bounce buffer pointed to by last trb */
3167 	if (usb_urb_dir_out(urb)) {
3168 		sg_pcopy_to_buffer(urb->sg, urb->num_mapped_sgs,
3169 				   seg->bounce_buf, new_buff_len, enqd_len);
3170 		seg->bounce_dma = dma_map_single(dev, seg->bounce_buf,
3171 						 max_pkt, DMA_TO_DEVICE);
3172 	} else {
3173 		seg->bounce_dma = dma_map_single(dev, seg->bounce_buf,
3174 						 max_pkt, DMA_FROM_DEVICE);
3175 	}
3176 
3177 	if (dma_mapping_error(dev, seg->bounce_dma)) {
3178 		/* try without aligning. Some host controllers survive */
3179 		xhci_warn(xhci, "Failed mapping bounce buffer, not aligning\n");
3180 		return 0;
3181 	}
3182 	*trb_buff_len = new_buff_len;
3183 	seg->bounce_len = new_buff_len;
3184 	seg->bounce_offs = enqd_len;
3185 
3186 	xhci_dbg(xhci, "Bounce align, new buff len %d\n", *trb_buff_len);
3187 
3188 	return 1;
3189 }
3190 
3191 /* This is very similar to what ehci-q.c qtd_fill() does */
3192 int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
3193 		struct urb *urb, int slot_id, unsigned int ep_index)
3194 {
3195 	struct xhci_ring *ring;
3196 	struct urb_priv *urb_priv;
3197 	struct xhci_td *td;
3198 	struct xhci_generic_trb *start_trb;
3199 	struct scatterlist *sg = NULL;
3200 	bool more_trbs_coming = true;
3201 	bool need_zero_pkt = false;
3202 	bool first_trb = true;
3203 	unsigned int num_trbs;
3204 	unsigned int start_cycle, num_sgs = 0;
3205 	unsigned int enqd_len, block_len, trb_buff_len, full_len;
3206 	int sent_len, ret;
3207 	u32 field, length_field, remainder;
3208 	u64 addr, send_addr;
3209 
3210 	ring = xhci_urb_to_transfer_ring(xhci, urb);
3211 	if (!ring)
3212 		return -EINVAL;
3213 
3214 	full_len = urb->transfer_buffer_length;
3215 	/* If we have scatter/gather list, we use it. */
3216 	if (urb->num_sgs) {
3217 		num_sgs = urb->num_mapped_sgs;
3218 		sg = urb->sg;
3219 		addr = (u64) sg_dma_address(sg);
3220 		block_len = sg_dma_len(sg);
3221 		num_trbs = count_sg_trbs_needed(urb);
3222 	} else {
3223 		num_trbs = count_trbs_needed(urb);
3224 		addr = (u64) urb->transfer_dma;
3225 		block_len = full_len;
3226 	}
3227 	ret = prepare_transfer(xhci, xhci->devs[slot_id],
3228 			ep_index, urb->stream_id,
3229 			num_trbs, urb, 0, mem_flags);
3230 	if (unlikely(ret < 0))
3231 		return ret;
3232 
3233 	urb_priv = urb->hcpriv;
3234 
3235 	/* Deal with URB_ZERO_PACKET - need one more td/trb */
3236 	if (urb->transfer_flags & URB_ZERO_PACKET && urb_priv->length > 1)
3237 		need_zero_pkt = true;
3238 
3239 	td = urb_priv->td[0];
3240 
3241 	/*
3242 	 * Don't give the first TRB to the hardware (by toggling the cycle bit)
3243 	 * until we've finished creating all the other TRBs.  The ring's cycle
3244 	 * state may change as we enqueue the other TRBs, so save it too.
3245 	 */
3246 	start_trb = &ring->enqueue->generic;
3247 	start_cycle = ring->cycle_state;
3248 	send_addr = addr;
3249 
3250 	/* Queue the TRBs, even if they are zero-length */
3251 	for (enqd_len = 0; first_trb || enqd_len < full_len;
3252 			enqd_len += trb_buff_len) {
3253 		field = TRB_TYPE(TRB_NORMAL);
3254 
3255 		/* TRB buffer should not cross 64KB boundaries */
3256 		trb_buff_len = TRB_BUFF_LEN_UP_TO_BOUNDARY(addr);
3257 		trb_buff_len = min_t(unsigned int, trb_buff_len, block_len);
3258 
3259 		if (enqd_len + trb_buff_len > full_len)
3260 			trb_buff_len = full_len - enqd_len;
3261 
3262 		/* Don't change the cycle bit of the first TRB until later */
3263 		if (first_trb) {
3264 			first_trb = false;
3265 			if (start_cycle == 0)
3266 				field |= TRB_CYCLE;
3267 		} else
3268 			field |= ring->cycle_state;
3269 
3270 		/* Chain all the TRBs together; clear the chain bit in the last
3271 		 * TRB to indicate it's the last TRB in the chain.
3272 		 */
3273 		if (enqd_len + trb_buff_len < full_len) {
3274 			field |= TRB_CHAIN;
3275 			if (trb_is_link(ring->enqueue + 1)) {
3276 				if (xhci_align_td(xhci, urb, enqd_len,
3277 						  &trb_buff_len,
3278 						  ring->enq_seg)) {
3279 					send_addr = ring->enq_seg->bounce_dma;
3280 					/* assuming TD won't span 2 segs */
3281 					td->bounce_seg = ring->enq_seg;
3282 				}
3283 			}
3284 		}
3285 		if (enqd_len + trb_buff_len >= full_len) {
3286 			field &= ~TRB_CHAIN;
3287 			field |= TRB_IOC;
3288 			more_trbs_coming = false;
3289 			td->last_trb = ring->enqueue;
3290 		}
3291 
3292 		/* Only set interrupt on short packet for IN endpoints */
3293 		if (usb_urb_dir_in(urb))
3294 			field |= TRB_ISP;
3295 
3296 		/* Set the TRB length, TD size, and interrupter fields. */
3297 		remainder = xhci_td_remainder(xhci, enqd_len, trb_buff_len,
3298 					      full_len, urb, more_trbs_coming);
3299 
3300 		length_field = TRB_LEN(trb_buff_len) |
3301 			TRB_TD_SIZE(remainder) |
3302 			TRB_INTR_TARGET(0);
3303 
3304 		queue_trb(xhci, ring, more_trbs_coming | need_zero_pkt,
3305 				lower_32_bits(send_addr),
3306 				upper_32_bits(send_addr),
3307 				length_field,
3308 				field);
3309 
3310 		addr += trb_buff_len;
3311 		sent_len = trb_buff_len;
3312 
3313 		while (sg && sent_len >= block_len) {
3314 			/* New sg entry */
3315 			--num_sgs;
3316 			sent_len -= block_len;
3317 			if (num_sgs != 0) {
3318 				sg = sg_next(sg);
3319 				block_len = sg_dma_len(sg);
3320 				addr = (u64) sg_dma_address(sg);
3321 				addr += sent_len;
3322 			}
3323 		}
3324 		block_len -= sent_len;
3325 		send_addr = addr;
3326 	}
3327 
3328 	if (need_zero_pkt) {
3329 		ret = prepare_transfer(xhci, xhci->devs[slot_id],
3330 				       ep_index, urb->stream_id,
3331 				       1, urb, 1, mem_flags);
3332 		urb_priv->td[1]->last_trb = ring->enqueue;
3333 		field = TRB_TYPE(TRB_NORMAL) | ring->cycle_state | TRB_IOC;
3334 		queue_trb(xhci, ring, 0, 0, 0, TRB_INTR_TARGET(0), field);
3335 	}
3336 
3337 	check_trb_math(urb, enqd_len);
3338 	giveback_first_trb(xhci, slot_id, ep_index, urb->stream_id,
3339 			start_cycle, start_trb);
3340 	return 0;
3341 }
3342 
3343 /* Caller must have locked xhci->lock */
3344 int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
3345 		struct urb *urb, int slot_id, unsigned int ep_index)
3346 {
3347 	struct xhci_ring *ep_ring;
3348 	int num_trbs;
3349 	int ret;
3350 	struct usb_ctrlrequest *setup;
3351 	struct xhci_generic_trb *start_trb;
3352 	int start_cycle;
3353 	u32 field, length_field, remainder;
3354 	struct urb_priv *urb_priv;
3355 	struct xhci_td *td;
3356 
3357 	ep_ring = xhci_urb_to_transfer_ring(xhci, urb);
3358 	if (!ep_ring)
3359 		return -EINVAL;
3360 
3361 	/*
3362 	 * Need to copy setup packet into setup TRB, so we can't use the setup
3363 	 * DMA address.
3364 	 */
3365 	if (!urb->setup_packet)
3366 		return -EINVAL;
3367 
3368 	/* 1 TRB for setup, 1 for status */
3369 	num_trbs = 2;
3370 	/*
3371 	 * Don't need to check if we need additional event data and normal TRBs,
3372 	 * since data in control transfers will never get bigger than 16MB
3373 	 * XXX: can we get a buffer that crosses 64KB boundaries?
3374 	 */
3375 	if (urb->transfer_buffer_length > 0)
3376 		num_trbs++;
3377 	ret = prepare_transfer(xhci, xhci->devs[slot_id],
3378 			ep_index, urb->stream_id,
3379 			num_trbs, urb, 0, mem_flags);
3380 	if (ret < 0)
3381 		return ret;
3382 
3383 	urb_priv = urb->hcpriv;
3384 	td = urb_priv->td[0];
3385 
3386 	/*
3387 	 * Don't give the first TRB to the hardware (by toggling the cycle bit)
3388 	 * until we've finished creating all the other TRBs.  The ring's cycle
3389 	 * state may change as we enqueue the other TRBs, so save it too.
3390 	 */
3391 	start_trb = &ep_ring->enqueue->generic;
3392 	start_cycle = ep_ring->cycle_state;
3393 
3394 	/* Queue setup TRB - see section 6.4.1.2.1 */
3395 	/* FIXME better way to translate setup_packet into two u32 fields? */
3396 	setup = (struct usb_ctrlrequest *) urb->setup_packet;
3397 	field = 0;
3398 	field |= TRB_IDT | TRB_TYPE(TRB_SETUP);
3399 	if (start_cycle == 0)
3400 		field |= 0x1;
3401 
3402 	/* xHCI 1.0/1.1 6.4.1.2.1: Transfer Type field */
3403 	if ((xhci->hci_version >= 0x100) || (xhci->quirks & XHCI_MTK_HOST)) {
3404 		if (urb->transfer_buffer_length > 0) {
3405 			if (setup->bRequestType & USB_DIR_IN)
3406 				field |= TRB_TX_TYPE(TRB_DATA_IN);
3407 			else
3408 				field |= TRB_TX_TYPE(TRB_DATA_OUT);
3409 		}
3410 	}
3411 
3412 	queue_trb(xhci, ep_ring, true,
3413 		  setup->bRequestType | setup->bRequest << 8 | le16_to_cpu(setup->wValue) << 16,
3414 		  le16_to_cpu(setup->wIndex) | le16_to_cpu(setup->wLength) << 16,
3415 		  TRB_LEN(8) | TRB_INTR_TARGET(0),
3416 		  /* Immediate data in pointer */
3417 		  field);
3418 
3419 	/* If there's data, queue data TRBs */
3420 	/* Only set interrupt on short packet for IN endpoints */
3421 	if (usb_urb_dir_in(urb))
3422 		field = TRB_ISP | TRB_TYPE(TRB_DATA);
3423 	else
3424 		field = TRB_TYPE(TRB_DATA);
3425 
3426 	remainder = xhci_td_remainder(xhci, 0,
3427 				   urb->transfer_buffer_length,
3428 				   urb->transfer_buffer_length,
3429 				   urb, 1);
3430 
3431 	length_field = TRB_LEN(urb->transfer_buffer_length) |
3432 		TRB_TD_SIZE(remainder) |
3433 		TRB_INTR_TARGET(0);
3434 
3435 	if (urb->transfer_buffer_length > 0) {
3436 		if (setup->bRequestType & USB_DIR_IN)
3437 			field |= TRB_DIR_IN;
3438 		queue_trb(xhci, ep_ring, true,
3439 				lower_32_bits(urb->transfer_dma),
3440 				upper_32_bits(urb->transfer_dma),
3441 				length_field,
3442 				field | ep_ring->cycle_state);
3443 	}
3444 
3445 	/* Save the DMA address of the last TRB in the TD */
3446 	td->last_trb = ep_ring->enqueue;
3447 
3448 	/* Queue status TRB - see Table 7 and sections 4.11.2.2 and 6.4.1.2.3 */
3449 	/* If the device sent data, the status stage is an OUT transfer */
3450 	if (urb->transfer_buffer_length > 0 && setup->bRequestType & USB_DIR_IN)
3451 		field = 0;
3452 	else
3453 		field = TRB_DIR_IN;
3454 	queue_trb(xhci, ep_ring, false,
3455 			0,
3456 			0,
3457 			TRB_INTR_TARGET(0),
3458 			/* Event on completion */
3459 			field | TRB_IOC | TRB_TYPE(TRB_STATUS) | ep_ring->cycle_state);
3460 
3461 	giveback_first_trb(xhci, slot_id, ep_index, 0,
3462 			start_cycle, start_trb);
3463 	return 0;
3464 }
3465 
3466 /*
3467  * The transfer burst count field of the isochronous TRB defines the number of
3468  * bursts that are required to move all packets in this TD.  Only SuperSpeed
3469  * devices can burst up to bMaxBurst number of packets per service interval.
3470  * This field is zero based, meaning a value of zero in the field means one
3471  * burst.  Basically, for everything but SuperSpeed devices, this field will be
3472  * zero.  Only xHCI 1.0 host controllers support this field.
3473  */
3474 static unsigned int xhci_get_burst_count(struct xhci_hcd *xhci,
3475 		struct urb *urb, unsigned int total_packet_count)
3476 {
3477 	unsigned int max_burst;
3478 
3479 	if (xhci->hci_version < 0x100 || urb->dev->speed < USB_SPEED_SUPER)
3480 		return 0;
3481 
3482 	max_burst = urb->ep->ss_ep_comp.bMaxBurst;
3483 	return DIV_ROUND_UP(total_packet_count, max_burst + 1) - 1;
3484 }
3485 
3486 /*
3487  * Returns the number of packets in the last "burst" of packets.  This field is
3488  * valid for all speeds of devices.  USB 2.0 devices can only do one "burst", so
3489  * the last burst packet count is equal to the total number of packets in the
3490  * TD.  SuperSpeed endpoints can have up to 3 bursts.  All but the last burst
3491  * must contain (bMaxBurst + 1) number of packets, but the last burst can
3492  * contain 1 to (bMaxBurst + 1) packets.
3493  */
3494 static unsigned int xhci_get_last_burst_packet_count(struct xhci_hcd *xhci,
3495 		struct urb *urb, unsigned int total_packet_count)
3496 {
3497 	unsigned int max_burst;
3498 	unsigned int residue;
3499 
3500 	if (xhci->hci_version < 0x100)
3501 		return 0;
3502 
3503 	if (urb->dev->speed >= USB_SPEED_SUPER) {
3504 		/* bMaxBurst is zero based: 0 means 1 packet per burst */
3505 		max_burst = urb->ep->ss_ep_comp.bMaxBurst;
3506 		residue = total_packet_count % (max_burst + 1);
3507 		/* If residue is zero, the last burst contains (max_burst + 1)
3508 		 * number of packets, but the TLBPC field is zero-based.
3509 		 */
3510 		if (residue == 0)
3511 			return max_burst;
3512 		return residue - 1;
3513 	}
3514 	if (total_packet_count == 0)
3515 		return 0;
3516 	return total_packet_count - 1;
3517 }
3518 
3519 /*
3520  * Calculates Frame ID field of the isochronous TRB identifies the
3521  * target frame that the Interval associated with this Isochronous
3522  * Transfer Descriptor will start on. Refer to 4.11.2.5 in 1.1 spec.
3523  *
3524  * Returns actual frame id on success, negative value on error.
3525  */
3526 static int xhci_get_isoc_frame_id(struct xhci_hcd *xhci,
3527 		struct urb *urb, int index)
3528 {
3529 	int start_frame, ist, ret = 0;
3530 	int start_frame_id, end_frame_id, current_frame_id;
3531 
3532 	if (urb->dev->speed == USB_SPEED_LOW ||
3533 			urb->dev->speed == USB_SPEED_FULL)
3534 		start_frame = urb->start_frame + index * urb->interval;
3535 	else
3536 		start_frame = (urb->start_frame + index * urb->interval) >> 3;
3537 
3538 	/* Isochronous Scheduling Threshold (IST, bits 0~3 in HCSPARAMS2):
3539 	 *
3540 	 * If bit [3] of IST is cleared to '0', software can add a TRB no
3541 	 * later than IST[2:0] Microframes before that TRB is scheduled to
3542 	 * be executed.
3543 	 * If bit [3] of IST is set to '1', software can add a TRB no later
3544 	 * than IST[2:0] Frames before that TRB is scheduled to be executed.
3545 	 */
3546 	ist = HCS_IST(xhci->hcs_params2) & 0x7;
3547 	if (HCS_IST(xhci->hcs_params2) & (1 << 3))
3548 		ist <<= 3;
3549 
3550 	/* Software shall not schedule an Isoch TD with a Frame ID value that
3551 	 * is less than the Start Frame ID or greater than the End Frame ID,
3552 	 * where:
3553 	 *
3554 	 * End Frame ID = (Current MFINDEX register value + 895 ms.) MOD 2048
3555 	 * Start Frame ID = (Current MFINDEX register value + IST + 1) MOD 2048
3556 	 *
3557 	 * Both the End Frame ID and Start Frame ID values are calculated
3558 	 * in microframes. When software determines the valid Frame ID value;
3559 	 * The End Frame ID value should be rounded down to the nearest Frame
3560 	 * boundary, and the Start Frame ID value should be rounded up to the
3561 	 * nearest Frame boundary.
3562 	 */
3563 	current_frame_id = readl(&xhci->run_regs->microframe_index);
3564 	start_frame_id = roundup(current_frame_id + ist + 1, 8);
3565 	end_frame_id = rounddown(current_frame_id + 895 * 8, 8);
3566 
3567 	start_frame &= 0x7ff;
3568 	start_frame_id = (start_frame_id >> 3) & 0x7ff;
3569 	end_frame_id = (end_frame_id >> 3) & 0x7ff;
3570 
3571 	xhci_dbg(xhci, "%s: index %d, reg 0x%x start_frame_id 0x%x, end_frame_id 0x%x, start_frame 0x%x\n",
3572 		 __func__, index, readl(&xhci->run_regs->microframe_index),
3573 		 start_frame_id, end_frame_id, start_frame);
3574 
3575 	if (start_frame_id < end_frame_id) {
3576 		if (start_frame > end_frame_id ||
3577 				start_frame < start_frame_id)
3578 			ret = -EINVAL;
3579 	} else if (start_frame_id > end_frame_id) {
3580 		if ((start_frame > end_frame_id &&
3581 				start_frame < start_frame_id))
3582 			ret = -EINVAL;
3583 	} else {
3584 			ret = -EINVAL;
3585 	}
3586 
3587 	if (index == 0) {
3588 		if (ret == -EINVAL || start_frame == start_frame_id) {
3589 			start_frame = start_frame_id + 1;
3590 			if (urb->dev->speed == USB_SPEED_LOW ||
3591 					urb->dev->speed == USB_SPEED_FULL)
3592 				urb->start_frame = start_frame;
3593 			else
3594 				urb->start_frame = start_frame << 3;
3595 			ret = 0;
3596 		}
3597 	}
3598 
3599 	if (ret) {
3600 		xhci_warn(xhci, "Frame ID %d (reg %d, index %d) beyond range (%d, %d)\n",
3601 				start_frame, current_frame_id, index,
3602 				start_frame_id, end_frame_id);
3603 		xhci_warn(xhci, "Ignore frame ID field, use SIA bit instead\n");
3604 		return ret;
3605 	}
3606 
3607 	return start_frame;
3608 }
3609 
3610 /* This is for isoc transfer */
3611 static int xhci_queue_isoc_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
3612 		struct urb *urb, int slot_id, unsigned int ep_index)
3613 {
3614 	struct xhci_ring *ep_ring;
3615 	struct urb_priv *urb_priv;
3616 	struct xhci_td *td;
3617 	int num_tds, trbs_per_td;
3618 	struct xhci_generic_trb *start_trb;
3619 	bool first_trb;
3620 	int start_cycle;
3621 	u32 field, length_field;
3622 	int running_total, trb_buff_len, td_len, td_remain_len, ret;
3623 	u64 start_addr, addr;
3624 	int i, j;
3625 	bool more_trbs_coming;
3626 	struct xhci_virt_ep *xep;
3627 	int frame_id;
3628 
3629 	xep = &xhci->devs[slot_id]->eps[ep_index];
3630 	ep_ring = xhci->devs[slot_id]->eps[ep_index].ring;
3631 
3632 	num_tds = urb->number_of_packets;
3633 	if (num_tds < 1) {
3634 		xhci_dbg(xhci, "Isoc URB with zero packets?\n");
3635 		return -EINVAL;
3636 	}
3637 	start_addr = (u64) urb->transfer_dma;
3638 	start_trb = &ep_ring->enqueue->generic;
3639 	start_cycle = ep_ring->cycle_state;
3640 
3641 	urb_priv = urb->hcpriv;
3642 	/* Queue the TRBs for each TD, even if they are zero-length */
3643 	for (i = 0; i < num_tds; i++) {
3644 		unsigned int total_pkt_count, max_pkt;
3645 		unsigned int burst_count, last_burst_pkt_count;
3646 		u32 sia_frame_id;
3647 
3648 		first_trb = true;
3649 		running_total = 0;
3650 		addr = start_addr + urb->iso_frame_desc[i].offset;
3651 		td_len = urb->iso_frame_desc[i].length;
3652 		td_remain_len = td_len;
3653 		max_pkt = GET_MAX_PACKET(usb_endpoint_maxp(&urb->ep->desc));
3654 		total_pkt_count = DIV_ROUND_UP(td_len, max_pkt);
3655 
3656 		/* A zero-length transfer still involves at least one packet. */
3657 		if (total_pkt_count == 0)
3658 			total_pkt_count++;
3659 		burst_count = xhci_get_burst_count(xhci, urb, total_pkt_count);
3660 		last_burst_pkt_count = xhci_get_last_burst_packet_count(xhci,
3661 							urb, total_pkt_count);
3662 
3663 		trbs_per_td = count_isoc_trbs_needed(urb, i);
3664 
3665 		ret = prepare_transfer(xhci, xhci->devs[slot_id], ep_index,
3666 				urb->stream_id, trbs_per_td, urb, i, mem_flags);
3667 		if (ret < 0) {
3668 			if (i == 0)
3669 				return ret;
3670 			goto cleanup;
3671 		}
3672 		td = urb_priv->td[i];
3673 
3674 		/* use SIA as default, if frame id is used overwrite it */
3675 		sia_frame_id = TRB_SIA;
3676 		if (!(urb->transfer_flags & URB_ISO_ASAP) &&
3677 		    HCC_CFC(xhci->hcc_params)) {
3678 			frame_id = xhci_get_isoc_frame_id(xhci, urb, i);
3679 			if (frame_id >= 0)
3680 				sia_frame_id = TRB_FRAME_ID(frame_id);
3681 		}
3682 		/*
3683 		 * Set isoc specific data for the first TRB in a TD.
3684 		 * Prevent HW from getting the TRBs by keeping the cycle state
3685 		 * inverted in the first TDs isoc TRB.
3686 		 */
3687 		field = TRB_TYPE(TRB_ISOC) |
3688 			TRB_TLBPC(last_burst_pkt_count) |
3689 			sia_frame_id |
3690 			(i ? ep_ring->cycle_state : !start_cycle);
3691 
3692 		/* xhci 1.1 with ETE uses TD_Size field for TBC, old is Rsvdz */
3693 		if (!xep->use_extended_tbc)
3694 			field |= TRB_TBC(burst_count);
3695 
3696 		/* fill the rest of the TRB fields, and remaining normal TRBs */
3697 		for (j = 0; j < trbs_per_td; j++) {
3698 			u32 remainder = 0;
3699 
3700 			/* only first TRB is isoc, overwrite otherwise */
3701 			if (!first_trb)
3702 				field = TRB_TYPE(TRB_NORMAL) |
3703 					ep_ring->cycle_state;
3704 
3705 			/* Only set interrupt on short packet for IN EPs */
3706 			if (usb_urb_dir_in(urb))
3707 				field |= TRB_ISP;
3708 
3709 			/* Set the chain bit for all except the last TRB  */
3710 			if (j < trbs_per_td - 1) {
3711 				more_trbs_coming = true;
3712 				field |= TRB_CHAIN;
3713 			} else {
3714 				more_trbs_coming = false;
3715 				td->last_trb = ep_ring->enqueue;
3716 				field |= TRB_IOC;
3717 				/* set BEI, except for the last TD */
3718 				if (xhci->hci_version >= 0x100 &&
3719 				    !(xhci->quirks & XHCI_AVOID_BEI) &&
3720 				    i < num_tds - 1)
3721 					field |= TRB_BEI;
3722 			}
3723 			/* Calculate TRB length */
3724 			trb_buff_len = TRB_BUFF_LEN_UP_TO_BOUNDARY(addr);
3725 			if (trb_buff_len > td_remain_len)
3726 				trb_buff_len = td_remain_len;
3727 
3728 			/* Set the TRB length, TD size, & interrupter fields. */
3729 			remainder = xhci_td_remainder(xhci, running_total,
3730 						   trb_buff_len, td_len,
3731 						   urb, more_trbs_coming);
3732 
3733 			length_field = TRB_LEN(trb_buff_len) |
3734 				TRB_INTR_TARGET(0);
3735 
3736 			/* xhci 1.1 with ETE uses TD Size field for TBC */
3737 			if (first_trb && xep->use_extended_tbc)
3738 				length_field |= TRB_TD_SIZE_TBC(burst_count);
3739 			else
3740 				length_field |= TRB_TD_SIZE(remainder);
3741 			first_trb = false;
3742 
3743 			queue_trb(xhci, ep_ring, more_trbs_coming,
3744 				lower_32_bits(addr),
3745 				upper_32_bits(addr),
3746 				length_field,
3747 				field);
3748 			running_total += trb_buff_len;
3749 
3750 			addr += trb_buff_len;
3751 			td_remain_len -= trb_buff_len;
3752 		}
3753 
3754 		/* Check TD length */
3755 		if (running_total != td_len) {
3756 			xhci_err(xhci, "ISOC TD length unmatch\n");
3757 			ret = -EINVAL;
3758 			goto cleanup;
3759 		}
3760 	}
3761 
3762 	/* store the next frame id */
3763 	if (HCC_CFC(xhci->hcc_params))
3764 		xep->next_frame_id = urb->start_frame + num_tds * urb->interval;
3765 
3766 	if (xhci_to_hcd(xhci)->self.bandwidth_isoc_reqs == 0) {
3767 		if (xhci->quirks & XHCI_AMD_PLL_FIX)
3768 			usb_amd_quirk_pll_disable();
3769 	}
3770 	xhci_to_hcd(xhci)->self.bandwidth_isoc_reqs++;
3771 
3772 	giveback_first_trb(xhci, slot_id, ep_index, urb->stream_id,
3773 			start_cycle, start_trb);
3774 	return 0;
3775 cleanup:
3776 	/* Clean up a partially enqueued isoc transfer. */
3777 
3778 	for (i--; i >= 0; i--)
3779 		list_del_init(&urb_priv->td[i]->td_list);
3780 
3781 	/* Use the first TD as a temporary variable to turn the TDs we've queued
3782 	 * into No-ops with a software-owned cycle bit. That way the hardware
3783 	 * won't accidentally start executing bogus TDs when we partially
3784 	 * overwrite them.  td->first_trb and td->start_seg are already set.
3785 	 */
3786 	urb_priv->td[0]->last_trb = ep_ring->enqueue;
3787 	/* Every TRB except the first & last will have its cycle bit flipped. */
3788 	td_to_noop(xhci, ep_ring, urb_priv->td[0], true);
3789 
3790 	/* Reset the ring enqueue back to the first TRB and its cycle bit. */
3791 	ep_ring->enqueue = urb_priv->td[0]->first_trb;
3792 	ep_ring->enq_seg = urb_priv->td[0]->start_seg;
3793 	ep_ring->cycle_state = start_cycle;
3794 	ep_ring->num_trbs_free = ep_ring->num_trbs_free_temp;
3795 	usb_hcd_unlink_urb_from_ep(bus_to_hcd(urb->dev->bus), urb);
3796 	return ret;
3797 }
3798 
3799 /*
3800  * Check transfer ring to guarantee there is enough room for the urb.
3801  * Update ISO URB start_frame and interval.
3802  * Update interval as xhci_queue_intr_tx does. Use xhci frame_index to
3803  * update urb->start_frame if URB_ISO_ASAP is set in transfer_flags or
3804  * Contiguous Frame ID is not supported by HC.
3805  */
3806 int xhci_queue_isoc_tx_prepare(struct xhci_hcd *xhci, gfp_t mem_flags,
3807 		struct urb *urb, int slot_id, unsigned int ep_index)
3808 {
3809 	struct xhci_virt_device *xdev;
3810 	struct xhci_ring *ep_ring;
3811 	struct xhci_ep_ctx *ep_ctx;
3812 	int start_frame;
3813 	int num_tds, num_trbs, i;
3814 	int ret;
3815 	struct xhci_virt_ep *xep;
3816 	int ist;
3817 
3818 	xdev = xhci->devs[slot_id];
3819 	xep = &xhci->devs[slot_id]->eps[ep_index];
3820 	ep_ring = xdev->eps[ep_index].ring;
3821 	ep_ctx = xhci_get_ep_ctx(xhci, xdev->out_ctx, ep_index);
3822 
3823 	num_trbs = 0;
3824 	num_tds = urb->number_of_packets;
3825 	for (i = 0; i < num_tds; i++)
3826 		num_trbs += count_isoc_trbs_needed(urb, i);
3827 
3828 	/* Check the ring to guarantee there is enough room for the whole urb.
3829 	 * Do not insert any td of the urb to the ring if the check failed.
3830 	 */
3831 	ret = prepare_ring(xhci, ep_ring, le32_to_cpu(ep_ctx->ep_info) & EP_STATE_MASK,
3832 			   num_trbs, mem_flags);
3833 	if (ret)
3834 		return ret;
3835 
3836 	/*
3837 	 * Check interval value. This should be done before we start to
3838 	 * calculate the start frame value.
3839 	 */
3840 	check_interval(xhci, urb, ep_ctx);
3841 
3842 	/* Calculate the start frame and put it in urb->start_frame. */
3843 	if (HCC_CFC(xhci->hcc_params) && !list_empty(&ep_ring->td_list)) {
3844 		if ((le32_to_cpu(ep_ctx->ep_info) & EP_STATE_MASK) ==
3845 				EP_STATE_RUNNING) {
3846 			urb->start_frame = xep->next_frame_id;
3847 			goto skip_start_over;
3848 		}
3849 	}
3850 
3851 	start_frame = readl(&xhci->run_regs->microframe_index);
3852 	start_frame &= 0x3fff;
3853 	/*
3854 	 * Round up to the next frame and consider the time before trb really
3855 	 * gets scheduled by hardare.
3856 	 */
3857 	ist = HCS_IST(xhci->hcs_params2) & 0x7;
3858 	if (HCS_IST(xhci->hcs_params2) & (1 << 3))
3859 		ist <<= 3;
3860 	start_frame += ist + XHCI_CFC_DELAY;
3861 	start_frame = roundup(start_frame, 8);
3862 
3863 	/*
3864 	 * Round up to the next ESIT (Endpoint Service Interval Time) if ESIT
3865 	 * is greate than 8 microframes.
3866 	 */
3867 	if (urb->dev->speed == USB_SPEED_LOW ||
3868 			urb->dev->speed == USB_SPEED_FULL) {
3869 		start_frame = roundup(start_frame, urb->interval << 3);
3870 		urb->start_frame = start_frame >> 3;
3871 	} else {
3872 		start_frame = roundup(start_frame, urb->interval);
3873 		urb->start_frame = start_frame;
3874 	}
3875 
3876 skip_start_over:
3877 	ep_ring->num_trbs_free_temp = ep_ring->num_trbs_free;
3878 
3879 	return xhci_queue_isoc_tx(xhci, mem_flags, urb, slot_id, ep_index);
3880 }
3881 
3882 /****		Command Ring Operations		****/
3883 
3884 /* Generic function for queueing a command TRB on the command ring.
3885  * Check to make sure there's room on the command ring for one command TRB.
3886  * Also check that there's room reserved for commands that must not fail.
3887  * If this is a command that must not fail, meaning command_must_succeed = TRUE,
3888  * then only check for the number of reserved spots.
3889  * Don't decrement xhci->cmd_ring_reserved_trbs after we've queued the TRB
3890  * because the command event handler may want to resubmit a failed command.
3891  */
3892 static int queue_command(struct xhci_hcd *xhci, struct xhci_command *cmd,
3893 			 u32 field1, u32 field2,
3894 			 u32 field3, u32 field4, bool command_must_succeed)
3895 {
3896 	int reserved_trbs = xhci->cmd_ring_reserved_trbs;
3897 	int ret;
3898 
3899 	if ((xhci->xhc_state & XHCI_STATE_DYING) ||
3900 		(xhci->xhc_state & XHCI_STATE_HALTED)) {
3901 		xhci_dbg(xhci, "xHCI dying or halted, can't queue_command\n");
3902 		return -ESHUTDOWN;
3903 	}
3904 
3905 	if (!command_must_succeed)
3906 		reserved_trbs++;
3907 
3908 	ret = prepare_ring(xhci, xhci->cmd_ring, EP_STATE_RUNNING,
3909 			reserved_trbs, GFP_ATOMIC);
3910 	if (ret < 0) {
3911 		xhci_err(xhci, "ERR: No room for command on command ring\n");
3912 		if (command_must_succeed)
3913 			xhci_err(xhci, "ERR: Reserved TRB counting for "
3914 					"unfailable commands failed.\n");
3915 		return ret;
3916 	}
3917 
3918 	cmd->command_trb = xhci->cmd_ring->enqueue;
3919 	list_add_tail(&cmd->cmd_list, &xhci->cmd_list);
3920 
3921 	/* if there are no other commands queued we start the timeout timer */
3922 	if (xhci->cmd_list.next == &cmd->cmd_list &&
3923 	    !timer_pending(&xhci->cmd_timer)) {
3924 		xhci->current_cmd = cmd;
3925 		mod_timer(&xhci->cmd_timer, jiffies + XHCI_CMD_DEFAULT_TIMEOUT);
3926 	}
3927 
3928 	queue_trb(xhci, xhci->cmd_ring, false, field1, field2, field3,
3929 			field4 | xhci->cmd_ring->cycle_state);
3930 	return 0;
3931 }
3932 
3933 /* Queue a slot enable or disable request on the command ring */
3934 int xhci_queue_slot_control(struct xhci_hcd *xhci, struct xhci_command *cmd,
3935 		u32 trb_type, u32 slot_id)
3936 {
3937 	return queue_command(xhci, cmd, 0, 0, 0,
3938 			TRB_TYPE(trb_type) | SLOT_ID_FOR_TRB(slot_id), false);
3939 }
3940 
3941 /* Queue an address device command TRB */
3942 int xhci_queue_address_device(struct xhci_hcd *xhci, struct xhci_command *cmd,
3943 		dma_addr_t in_ctx_ptr, u32 slot_id, enum xhci_setup_dev setup)
3944 {
3945 	return queue_command(xhci, cmd, lower_32_bits(in_ctx_ptr),
3946 			upper_32_bits(in_ctx_ptr), 0,
3947 			TRB_TYPE(TRB_ADDR_DEV) | SLOT_ID_FOR_TRB(slot_id)
3948 			| (setup == SETUP_CONTEXT_ONLY ? TRB_BSR : 0), false);
3949 }
3950 
3951 int xhci_queue_vendor_command(struct xhci_hcd *xhci, struct xhci_command *cmd,
3952 		u32 field1, u32 field2, u32 field3, u32 field4)
3953 {
3954 	return queue_command(xhci, cmd, field1, field2, field3, field4, false);
3955 }
3956 
3957 /* Queue a reset device command TRB */
3958 int xhci_queue_reset_device(struct xhci_hcd *xhci, struct xhci_command *cmd,
3959 		u32 slot_id)
3960 {
3961 	return queue_command(xhci, cmd, 0, 0, 0,
3962 			TRB_TYPE(TRB_RESET_DEV) | SLOT_ID_FOR_TRB(slot_id),
3963 			false);
3964 }
3965 
3966 /* Queue a configure endpoint command TRB */
3967 int xhci_queue_configure_endpoint(struct xhci_hcd *xhci,
3968 		struct xhci_command *cmd, dma_addr_t in_ctx_ptr,
3969 		u32 slot_id, bool command_must_succeed)
3970 {
3971 	return queue_command(xhci, cmd, lower_32_bits(in_ctx_ptr),
3972 			upper_32_bits(in_ctx_ptr), 0,
3973 			TRB_TYPE(TRB_CONFIG_EP) | SLOT_ID_FOR_TRB(slot_id),
3974 			command_must_succeed);
3975 }
3976 
3977 /* Queue an evaluate context command TRB */
3978 int xhci_queue_evaluate_context(struct xhci_hcd *xhci, struct xhci_command *cmd,
3979 		dma_addr_t in_ctx_ptr, u32 slot_id, bool command_must_succeed)
3980 {
3981 	return queue_command(xhci, cmd, lower_32_bits(in_ctx_ptr),
3982 			upper_32_bits(in_ctx_ptr), 0,
3983 			TRB_TYPE(TRB_EVAL_CONTEXT) | SLOT_ID_FOR_TRB(slot_id),
3984 			command_must_succeed);
3985 }
3986 
3987 /*
3988  * Suspend is set to indicate "Stop Endpoint Command" is being issued to stop
3989  * activity on an endpoint that is about to be suspended.
3990  */
3991 int xhci_queue_stop_endpoint(struct xhci_hcd *xhci, struct xhci_command *cmd,
3992 			     int slot_id, unsigned int ep_index, int suspend)
3993 {
3994 	u32 trb_slot_id = SLOT_ID_FOR_TRB(slot_id);
3995 	u32 trb_ep_index = EP_ID_FOR_TRB(ep_index);
3996 	u32 type = TRB_TYPE(TRB_STOP_RING);
3997 	u32 trb_suspend = SUSPEND_PORT_FOR_TRB(suspend);
3998 
3999 	return queue_command(xhci, cmd, 0, 0, 0,
4000 			trb_slot_id | trb_ep_index | type | trb_suspend, false);
4001 }
4002 
4003 /* Set Transfer Ring Dequeue Pointer command */
4004 void xhci_queue_new_dequeue_state(struct xhci_hcd *xhci,
4005 		unsigned int slot_id, unsigned int ep_index,
4006 		unsigned int stream_id,
4007 		struct xhci_dequeue_state *deq_state)
4008 {
4009 	dma_addr_t addr;
4010 	u32 trb_slot_id = SLOT_ID_FOR_TRB(slot_id);
4011 	u32 trb_ep_index = EP_ID_FOR_TRB(ep_index);
4012 	u32 trb_stream_id = STREAM_ID_FOR_TRB(stream_id);
4013 	u32 trb_sct = 0;
4014 	u32 type = TRB_TYPE(TRB_SET_DEQ);
4015 	struct xhci_virt_ep *ep;
4016 	struct xhci_command *cmd;
4017 	int ret;
4018 
4019 	xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
4020 		"Set TR Deq Ptr cmd, new deq seg = %p (0x%llx dma), new deq ptr = %p (0x%llx dma), new cycle = %u",
4021 		deq_state->new_deq_seg,
4022 		(unsigned long long)deq_state->new_deq_seg->dma,
4023 		deq_state->new_deq_ptr,
4024 		(unsigned long long)xhci_trb_virt_to_dma(
4025 			deq_state->new_deq_seg, deq_state->new_deq_ptr),
4026 		deq_state->new_cycle_state);
4027 
4028 	addr = xhci_trb_virt_to_dma(deq_state->new_deq_seg,
4029 				    deq_state->new_deq_ptr);
4030 	if (addr == 0) {
4031 		xhci_warn(xhci, "WARN Cannot submit Set TR Deq Ptr\n");
4032 		xhci_warn(xhci, "WARN deq seg = %p, deq pt = %p\n",
4033 			  deq_state->new_deq_seg, deq_state->new_deq_ptr);
4034 		return;
4035 	}
4036 	ep = &xhci->devs[slot_id]->eps[ep_index];
4037 	if ((ep->ep_state & SET_DEQ_PENDING)) {
4038 		xhci_warn(xhci, "WARN Cannot submit Set TR Deq Ptr\n");
4039 		xhci_warn(xhci, "A Set TR Deq Ptr command is pending.\n");
4040 		return;
4041 	}
4042 
4043 	/* This function gets called from contexts where it cannot sleep */
4044 	cmd = xhci_alloc_command(xhci, false, false, GFP_ATOMIC);
4045 	if (!cmd) {
4046 		xhci_warn(xhci, "WARN Cannot submit Set TR Deq Ptr: ENOMEM\n");
4047 		return;
4048 	}
4049 
4050 	ep->queued_deq_seg = deq_state->new_deq_seg;
4051 	ep->queued_deq_ptr = deq_state->new_deq_ptr;
4052 	if (stream_id)
4053 		trb_sct = SCT_FOR_TRB(SCT_PRI_TR);
4054 	ret = queue_command(xhci, cmd,
4055 		lower_32_bits(addr) | trb_sct | deq_state->new_cycle_state,
4056 		upper_32_bits(addr), trb_stream_id,
4057 		trb_slot_id | trb_ep_index | type, false);
4058 	if (ret < 0) {
4059 		xhci_free_command(xhci, cmd);
4060 		return;
4061 	}
4062 
4063 	/* Stop the TD queueing code from ringing the doorbell until
4064 	 * this command completes.  The HC won't set the dequeue pointer
4065 	 * if the ring is running, and ringing the doorbell starts the
4066 	 * ring running.
4067 	 */
4068 	ep->ep_state |= SET_DEQ_PENDING;
4069 }
4070 
4071 int xhci_queue_reset_ep(struct xhci_hcd *xhci, struct xhci_command *cmd,
4072 			int slot_id, unsigned int ep_index)
4073 {
4074 	u32 trb_slot_id = SLOT_ID_FOR_TRB(slot_id);
4075 	u32 trb_ep_index = EP_ID_FOR_TRB(ep_index);
4076 	u32 type = TRB_TYPE(TRB_RESET_EP);
4077 
4078 	return queue_command(xhci, cmd, 0, 0, 0,
4079 			trb_slot_id | trb_ep_index | type, false);
4080 }
4081