xref: /netbsd-src/sys/dev/usb/usbdi.c (revision 53b02e147d4ed531c0d2a5ca9b3e8026ba3e99b5)
1 /*	$NetBSD: usbdi.c,v 1.220 2021/12/21 09:51:22 skrll Exp $	*/
2 
3 /*
4  * Copyright (c) 1998, 2012, 2015 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Lennart Augustsson (lennart@augustsson.net) at
9  * Carlstedt Research & Technology, Matthew R. Green (mrg@eterna.com.au),
10  * and Nick Hudson.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
23  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: usbdi.c,v 1.220 2021/12/21 09:51:22 skrll Exp $");
36 
37 #ifdef _KERNEL_OPT
38 #include "opt_usb.h"
39 #include "opt_compat_netbsd.h"
40 #include "usb_dma.h"
41 #endif
42 
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/kernel.h>
46 #include <sys/device.h>
47 #include <sys/kmem.h>
48 #include <sys/proc.h>
49 #include <sys/bus.h>
50 #include <sys/cpu.h>
51 
52 #include <dev/usb/usb.h>
53 #include <dev/usb/usbdi.h>
54 #include <dev/usb/usbdi_util.h>
55 #include <dev/usb/usbdivar.h>
56 #include <dev/usb/usb_mem.h>
57 #include <dev/usb/usb_quirks.h>
58 #include <dev/usb/usb_sdt.h>
59 #include <dev/usb/usbhist.h>
60 
61 /* UTF-8 encoding stuff */
62 #include <fs/unicode.h>
63 
64 extern int usbdebug;
65 
66 SDT_PROBE_DEFINE5(usb, device, pipe, open,
67     "struct usbd_interface *"/*iface*/,
68     "uint8_t"/*address*/,
69     "uint8_t"/*flags*/,
70     "int"/*ival*/,
71     "struct usbd_pipe *"/*pipe*/);
72 
73 SDT_PROBE_DEFINE7(usb, device, pipe, open__intr,
74     "struct usbd_interface *"/*iface*/,
75     "uint8_t"/*address*/,
76     "uint8_t"/*flags*/,
77     "int"/*ival*/,
78     "usbd_callback"/*cb*/,
79     "void *"/*cookie*/,
80     "struct usbd_pipe *"/*pipe*/);
81 
82 SDT_PROBE_DEFINE2(usb, device, pipe, transfer__start,
83     "struct usbd_pipe *"/*pipe*/,
84     "struct usbd_xfer *"/*xfer*/);
85 SDT_PROBE_DEFINE3(usb, device, pipe, transfer__done,
86     "struct usbd_pipe *"/*pipe*/,
87     "struct usbd_xfer *"/*xfer*/,
88     "usbd_status"/*err*/);
89 SDT_PROBE_DEFINE2(usb, device, pipe, start,
90     "struct usbd_pipe *"/*pipe*/,
91     "struct usbd_xfer *"/*xfer*/);
92 
93 SDT_PROBE_DEFINE1(usb, device, pipe, close,  "struct usbd_pipe *"/*pipe*/);
94 SDT_PROBE_DEFINE1(usb, device, pipe, abort__start,
95     "struct usbd_pipe *"/*pipe*/);
96 SDT_PROBE_DEFINE1(usb, device, pipe, abort__done,
97     "struct usbd_pipe *"/*pipe*/);
98 SDT_PROBE_DEFINE1(usb, device, pipe, clear__endpoint__stall,
99     "struct usbd_pipe *"/*pipe*/);
100 SDT_PROBE_DEFINE1(usb, device, pipe, clear__endpoint__toggle,
101     "struct usbd_pipe *"/*pipe*/);
102 
103 SDT_PROBE_DEFINE5(usb, device, xfer, create,
104     "struct usbd_xfer *"/*xfer*/,
105     "struct usbd_pipe *"/*pipe*/,
106     "size_t"/*len*/,
107     "unsigned int"/*flags*/,
108     "unsigned int"/*nframes*/);
109 SDT_PROBE_DEFINE1(usb, device, xfer, start,  "struct usbd_xfer *"/*xfer*/);
110 SDT_PROBE_DEFINE1(usb, device, xfer, preabort,  "struct usbd_xfer *"/*xfer*/);
111 SDT_PROBE_DEFINE1(usb, device, xfer, abort,  "struct usbd_xfer *"/*xfer*/);
112 SDT_PROBE_DEFINE1(usb, device, xfer, timeout,  "struct usbd_xfer *"/*xfer*/);
113 SDT_PROBE_DEFINE2(usb, device, xfer, done,
114     "struct usbd_xfer *"/*xfer*/,
115     "usbd_status"/*status*/);
116 SDT_PROBE_DEFINE1(usb, device, xfer, destroy,  "struct usbd_xfer *"/*xfer*/);
117 
118 Static usbd_status usbd_ar_pipe(struct usbd_pipe *);
119 Static void usbd_start_next(struct usbd_pipe *);
120 Static usbd_status usbd_open_pipe_ival
121 	(struct usbd_interface *, uint8_t, uint8_t, struct usbd_pipe **, int);
122 static void *usbd_alloc_buffer(struct usbd_xfer *, uint32_t);
123 static void usbd_free_buffer(struct usbd_xfer *);
124 static struct usbd_xfer *usbd_alloc_xfer(struct usbd_device *, unsigned int);
125 static usbd_status usbd_free_xfer(struct usbd_xfer *);
126 static void usbd_request_async_cb(struct usbd_xfer *, void *, usbd_status);
127 static void usbd_xfer_timeout(void *);
128 static void usbd_xfer_timeout_task(void *);
129 static bool usbd_xfer_probe_timeout(struct usbd_xfer *);
130 static void usbd_xfer_cancel_timeout_async(struct usbd_xfer *);
131 
132 #if defined(USB_DEBUG)
133 void
134 usbd_dump_iface(struct usbd_interface *iface)
135 {
136 	USBHIST_FUNC();
137 	USBHIST_CALLARGS(usbdebug, "iface %#jx", (uintptr_t)iface, 0, 0, 0);
138 
139 	if (iface == NULL)
140 		return;
141 	USBHIST_LOG(usbdebug, "     device = %#jx idesc = %#jx index = %jd",
142 	    (uintptr_t)iface->ui_dev, (uintptr_t)iface->ui_idesc,
143 	    iface->ui_index, 0);
144 	USBHIST_LOG(usbdebug, "     altindex=%jd",
145 	    iface->ui_altindex, 0, 0, 0);
146 }
147 
148 void
149 usbd_dump_device(struct usbd_device *dev)
150 {
151 	USBHIST_FUNC();
152 	USBHIST_CALLARGS(usbdebug, "dev = %#jx", (uintptr_t)dev, 0, 0, 0);
153 
154 	if (dev == NULL)
155 		return;
156 	USBHIST_LOG(usbdebug, "     bus = %#jx default_pipe = %#jx",
157 	    (uintptr_t)dev->ud_bus, (uintptr_t)dev->ud_pipe0, 0, 0);
158 	USBHIST_LOG(usbdebug, "     address = %jd config = %jd depth = %jd ",
159 	    dev->ud_addr, dev->ud_config, dev->ud_depth, 0);
160 	USBHIST_LOG(usbdebug, "     speed = %jd self_powered = %jd "
161 	    "power = %jd langid = %jd",
162 	    dev->ud_speed, dev->ud_selfpowered, dev->ud_power, dev->ud_langid);
163 }
164 
165 void
166 usbd_dump_endpoint(struct usbd_endpoint *endp)
167 {
168 	USBHIST_FUNC();
169 	USBHIST_CALLARGS(usbdebug, "endp = %#jx", (uintptr_t)endp, 0, 0, 0);
170 
171 	if (endp == NULL)
172 		return;
173 	USBHIST_LOG(usbdebug, "    edesc = %#jx refcnt = %jd",
174 	    (uintptr_t)endp->ue_edesc, endp->ue_refcnt, 0, 0);
175 	if (endp->ue_edesc)
176 		USBHIST_LOG(usbdebug, "     bEndpointAddress=0x%02jx",
177 		    endp->ue_edesc->bEndpointAddress, 0, 0, 0);
178 }
179 
180 void
181 usbd_dump_queue(struct usbd_pipe *pipe)
182 {
183 	struct usbd_xfer *xfer;
184 
185 	USBHIST_FUNC();
186 	USBHIST_CALLARGS(usbdebug, "pipe = %#jx", (uintptr_t)pipe, 0, 0, 0);
187 
188 	SIMPLEQ_FOREACH(xfer, &pipe->up_queue, ux_next) {
189 		USBHIST_LOG(usbdebug, "     xfer = %#jx", (uintptr_t)xfer,
190 		    0, 0, 0);
191 	}
192 }
193 
194 void
195 usbd_dump_pipe(struct usbd_pipe *pipe)
196 {
197 	USBHIST_FUNC();
198 	USBHIST_CALLARGS(usbdebug, "pipe = %#jx", (uintptr_t)pipe, 0, 0, 0);
199 
200 	if (pipe == NULL)
201 		return;
202 	usbd_dump_iface(pipe->up_iface);
203 	usbd_dump_device(pipe->up_dev);
204 	usbd_dump_endpoint(pipe->up_endpoint);
205 	USBHIST_LOG(usbdebug, "(usbd_dump_pipe)", 0, 0, 0, 0);
206 	USBHIST_LOG(usbdebug, "     running = %jd aborting = %jd",
207 	    pipe->up_running, pipe->up_aborting, 0, 0);
208 	USBHIST_LOG(usbdebug, "     intrxfer = %#jx, repeat = %jd, "
209 	    "interval = %jd", (uintptr_t)pipe->up_intrxfer, pipe->up_repeat,
210 	    pipe->up_interval, 0);
211 }
212 #endif
213 
214 usbd_status
215 usbd_open_pipe(struct usbd_interface *iface, uint8_t address,
216 	       uint8_t flags, struct usbd_pipe **pipe)
217 {
218 	return (usbd_open_pipe_ival(iface, address, flags, pipe,
219 				    USBD_DEFAULT_INTERVAL));
220 }
221 
222 usbd_status
223 usbd_open_pipe_ival(struct usbd_interface *iface, uint8_t address,
224 		    uint8_t flags, struct usbd_pipe **pipe, int ival)
225 {
226 	struct usbd_pipe *p = NULL;
227 	struct usbd_endpoint *ep = NULL /* XXXGCC */;
228 	bool piperef = false;
229 	usbd_status err;
230 	int i;
231 
232 	USBHIST_FUNC();
233 	USBHIST_CALLARGS(usbdebug, "iface = %#jx address = %#jx flags = %#jx",
234 	    (uintptr_t)iface, address, flags, 0);
235 
236 	/*
237 	 * Block usbd_set_interface so we have a snapshot of the
238 	 * interface endpoints.  They will remain stable until we drop
239 	 * the reference in usbd_close_pipe (or on failure here).
240 	 */
241 	err = usbd_iface_piperef(iface);
242 	if (err)
243 		goto out;
244 	piperef = true;
245 
246 	/* Find the endpoint at this address.  */
247 	for (i = 0; i < iface->ui_idesc->bNumEndpoints; i++) {
248 		ep = &iface->ui_endpoints[i];
249 		if (ep->ue_edesc == NULL) {
250 			err = USBD_IOERROR;
251 			goto out;
252 		}
253 		if (ep->ue_edesc->bEndpointAddress == address)
254 			break;
255 	}
256 	if (i == iface->ui_idesc->bNumEndpoints) {
257 		err = USBD_BAD_ADDRESS;
258 		goto out;
259 	}
260 
261 	/* Set up the pipe with this endpoint.  */
262 	err = usbd_setup_pipe_flags(iface->ui_dev, iface, ep, ival, &p, flags);
263 	if (err)
264 		goto out;
265 
266 	/* Success! */
267 	*pipe = p;
268 	p = NULL;		/* handed off to caller */
269 	piperef = false;	/* handed off to pipe */
270 	SDT_PROBE5(usb, device, pipe, open,
271 	    iface, address, flags, ival, p);
272 	err = USBD_NORMAL_COMPLETION;
273 
274 out:	if (p)
275 		usbd_close_pipe(p);
276 	if (piperef)
277 		usbd_iface_pipeunref(iface);
278 	return err;
279 }
280 
281 usbd_status
282 usbd_open_pipe_intr(struct usbd_interface *iface, uint8_t address,
283 		    uint8_t flags, struct usbd_pipe **pipe,
284 		    void *priv, void *buffer, uint32_t len,
285 		    usbd_callback cb, int ival)
286 {
287 	usbd_status err;
288 	struct usbd_xfer *xfer;
289 	struct usbd_pipe *ipipe;
290 
291 	USBHIST_FUNC();
292 	USBHIST_CALLARGS(usbdebug, "address = %#jx flags = %#jx len = %jd",
293 	    address, flags, len, 0);
294 
295 	err = usbd_open_pipe_ival(iface, address,
296 				  USBD_EXCLUSIVE_USE | (flags & USBD_MPSAFE),
297 				  &ipipe, ival);
298 	if (err)
299 		return err;
300 	err = usbd_create_xfer(ipipe, len, flags, 0, &xfer);
301 	if (err)
302 		goto bad1;
303 
304 	usbd_setup_xfer(xfer, priv, buffer, len, flags, USBD_NO_TIMEOUT, cb);
305 	ipipe->up_intrxfer = xfer;
306 	ipipe->up_repeat = 1;
307 	err = usbd_transfer(xfer);
308 	*pipe = ipipe;
309 	if (err != USBD_IN_PROGRESS)
310 		goto bad3;
311 	SDT_PROBE7(usb, device, pipe, open__intr,
312 	    iface, address, flags, ival, cb, priv, ipipe);
313 	return USBD_NORMAL_COMPLETION;
314 
315  bad3:
316 	ipipe->up_intrxfer = NULL;
317 	ipipe->up_repeat = 0;
318 
319 	usbd_destroy_xfer(xfer);
320  bad1:
321 	usbd_close_pipe(ipipe);
322 	return err;
323 }
324 
325 usbd_status
326 usbd_close_pipe(struct usbd_pipe *pipe)
327 {
328 	USBHIST_FUNC(); USBHIST_CALLED(usbdebug);
329 
330 	KASSERT(pipe != NULL);
331 
332 	usbd_lock_pipe(pipe);
333 	SDT_PROBE1(usb, device, pipe, close,  pipe);
334 	if (!SIMPLEQ_EMPTY(&pipe->up_queue)) {
335 		printf("WARNING: pipe closed with active xfers on addr %d\n",
336 		    pipe->up_dev->ud_addr);
337 		usbd_ar_pipe(pipe);
338 	}
339 	KASSERT(SIMPLEQ_EMPTY(&pipe->up_queue));
340 	pipe->up_methods->upm_close(pipe);
341 	usbd_unlock_pipe(pipe);
342 
343 	cv_destroy(&pipe->up_callingcv);
344 	if (pipe->up_intrxfer)
345 		usbd_destroy_xfer(pipe->up_intrxfer);
346 	usb_rem_task_wait(pipe->up_dev, &pipe->up_async_task, USB_TASKQ_DRIVER,
347 	    NULL);
348 	usbd_endpoint_release(pipe->up_dev, pipe->up_endpoint);
349 	if (pipe->up_iface)
350 		usbd_iface_pipeunref(pipe->up_iface);
351 	kmem_free(pipe, pipe->up_dev->ud_bus->ub_pipesize);
352 
353 	return USBD_NORMAL_COMPLETION;
354 }
355 
356 usbd_status
357 usbd_transfer(struct usbd_xfer *xfer)
358 {
359 	struct usbd_pipe *pipe = xfer->ux_pipe;
360 	usbd_status err;
361 	unsigned int size, flags;
362 
363 	USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug,
364 	    "xfer = %#jx, flags = %#jx, pipe = %#jx, running = %jd",
365 	    (uintptr_t)xfer, xfer->ux_flags, (uintptr_t)pipe, pipe->up_running);
366 	KASSERT(xfer->ux_status == USBD_NOT_STARTED);
367 	SDT_PROBE1(usb, device, xfer, start,  xfer);
368 
369 #ifdef USB_DEBUG
370 	if (usbdebug > 5)
371 		usbd_dump_queue(pipe);
372 #endif
373 	xfer->ux_done = 0;
374 
375 	if (pipe->up_aborting) {
376 		USBHIST_LOG(usbdebug, "<- done xfer %#jx, aborting",
377 		    (uintptr_t)xfer, 0, 0, 0);
378 		SDT_PROBE2(usb, device, xfer, done,  xfer, USBD_CANCELLED);
379 		return USBD_CANCELLED;
380 	}
381 
382 	KASSERT(xfer->ux_length == 0 || xfer->ux_buf != NULL);
383 
384 	size = xfer->ux_length;
385 	flags = xfer->ux_flags;
386 
387 	if (size != 0) {
388 		/*
389 		 * Use the xfer buffer if none specified in transfer setup.
390 		 * isoc transfers always use the xfer buffer, i.e.
391 		 * ux_buffer is always NULL for isoc.
392 		 */
393 		if (xfer->ux_buffer == NULL) {
394 			xfer->ux_buffer = xfer->ux_buf;
395 		}
396 
397 		/*
398 		 * If not using the xfer buffer copy data to the
399 		 * xfer buffer for OUT transfers of >0 length
400 		 */
401 		if (xfer->ux_buffer != xfer->ux_buf) {
402 			KASSERT(xfer->ux_buf);
403 			if (!usbd_xfer_isread(xfer)) {
404 				memcpy(xfer->ux_buf, xfer->ux_buffer, size);
405 			}
406 		}
407 	}
408 
409 	/* xfer is not valid after the transfer method unless synchronous */
410 	SDT_PROBE2(usb, device, pipe, transfer__start,  pipe, xfer);
411 	err = pipe->up_methods->upm_transfer(xfer);
412 	SDT_PROBE3(usb, device, pipe, transfer__done,  pipe, xfer, err);
413 
414 	if (err != USBD_IN_PROGRESS && err) {
415 		/*
416 		 * The transfer made it onto the pipe queue, but didn't get
417 		 * accepted by the HCD for some reason.  It needs removing
418 		 * from the pipe queue.
419 		 */
420 		USBHIST_LOG(usbdebug, "xfer failed: %jd, reinserting",
421 		    err, 0, 0, 0);
422 		usbd_lock_pipe(pipe);
423 		SDT_PROBE1(usb, device, xfer, preabort,  xfer);
424 #ifdef DIAGNOSTIC
425 		xfer->ux_state = XFER_BUSY;
426 #endif
427 		SIMPLEQ_REMOVE_HEAD(&pipe->up_queue, ux_next);
428 		if (pipe->up_serialise)
429 			usbd_start_next(pipe);
430 		usbd_unlock_pipe(pipe);
431 	}
432 
433 	if (!(flags & USBD_SYNCHRONOUS)) {
434 		USBHIST_LOG(usbdebug, "<- done xfer %#jx, not sync (err %jd)",
435 		    (uintptr_t)xfer, err, 0, 0);
436 		if (err != USBD_IN_PROGRESS) /* XXX Possible?  */
437 			SDT_PROBE2(usb, device, xfer, done,  xfer, err);
438 		return err;
439 	}
440 
441 	if (err != USBD_IN_PROGRESS) {
442 		USBHIST_LOG(usbdebug, "<- done xfer %#jx, sync (err %jd)",
443 		    (uintptr_t)xfer, err, 0, 0);
444 		SDT_PROBE2(usb, device, xfer, done,  xfer, err);
445 		return err;
446 	}
447 
448 	/* Sync transfer, wait for completion. */
449 	usbd_lock_pipe(pipe);
450 	while (!xfer->ux_done) {
451 		if (pipe->up_dev->ud_bus->ub_usepolling)
452 			panic("usbd_transfer: not done");
453 		USBHIST_LOG(usbdebug, "<- sleeping on xfer %#jx",
454 		    (uintptr_t)xfer, 0, 0, 0);
455 
456 		err = 0;
457 		if ((flags & USBD_SYNCHRONOUS_SIG) != 0) {
458 			err = cv_wait_sig(&xfer->ux_cv, pipe->up_dev->ud_bus->ub_lock);
459 		} else {
460 			cv_wait(&xfer->ux_cv, pipe->up_dev->ud_bus->ub_lock);
461 		}
462 		if (err) {
463 			if (!xfer->ux_done) {
464 				SDT_PROBE1(usb, device, xfer, abort,  xfer);
465 				pipe->up_methods->upm_abort(xfer);
466 			}
467 			break;
468 		}
469 	}
470 	SDT_PROBE2(usb, device, xfer, done,  xfer, xfer->ux_status);
471 	/* XXX Race to read xfer->ux_status?  */
472 	usbd_unlock_pipe(pipe);
473 	return xfer->ux_status;
474 }
475 
476 /* Like usbd_transfer(), but waits for completion. */
477 usbd_status
478 usbd_sync_transfer(struct usbd_xfer *xfer)
479 {
480 	xfer->ux_flags |= USBD_SYNCHRONOUS;
481 	return usbd_transfer(xfer);
482 }
483 
484 /* Like usbd_transfer(), but waits for completion and listens for signals. */
485 usbd_status
486 usbd_sync_transfer_sig(struct usbd_xfer *xfer)
487 {
488 	xfer->ux_flags |= USBD_SYNCHRONOUS | USBD_SYNCHRONOUS_SIG;
489 	return usbd_transfer(xfer);
490 }
491 
492 static void *
493 usbd_alloc_buffer(struct usbd_xfer *xfer, uint32_t size)
494 {
495 	KASSERT(xfer->ux_buf == NULL);
496 	KASSERT(size != 0);
497 
498 	xfer->ux_bufsize = 0;
499 #if NUSB_DMA > 0
500 	struct usbd_bus *bus = xfer->ux_bus;
501 
502 	if (bus->ub_usedma) {
503 		usb_dma_t *dmap = &xfer->ux_dmabuf;
504 
505 		KASSERT((bus->ub_dmaflags & USBMALLOC_COHERENT) == 0);
506 		int err = usb_allocmem(bus->ub_dmatag, size, 0, bus->ub_dmaflags, dmap);
507 		if (err) {
508 			return NULL;
509 		}
510 		xfer->ux_buf = KERNADDR(&xfer->ux_dmabuf, 0);
511 		xfer->ux_bufsize = size;
512 
513 		return xfer->ux_buf;
514 	}
515 #endif
516 	KASSERT(xfer->ux_bus->ub_usedma == false);
517 	xfer->ux_buf = kmem_alloc(size, KM_SLEEP);
518 	xfer->ux_bufsize = size;
519 	return xfer->ux_buf;
520 }
521 
522 static void
523 usbd_free_buffer(struct usbd_xfer *xfer)
524 {
525 	KASSERT(xfer->ux_buf != NULL);
526 	KASSERT(xfer->ux_bufsize != 0);
527 
528 	void *buf = xfer->ux_buf;
529 	uint32_t size = xfer->ux_bufsize;
530 
531 	xfer->ux_buf = NULL;
532 	xfer->ux_bufsize = 0;
533 
534 #if NUSB_DMA > 0
535 	struct usbd_bus *bus = xfer->ux_bus;
536 
537 	if (bus->ub_usedma) {
538 		usb_dma_t *dmap = &xfer->ux_dmabuf;
539 
540 		usb_freemem(dmap);
541 		return;
542 	}
543 #endif
544 	KASSERT(xfer->ux_bus->ub_usedma == false);
545 
546 	kmem_free(buf, size);
547 }
548 
549 void *
550 usbd_get_buffer(struct usbd_xfer *xfer)
551 {
552 	return xfer->ux_buf;
553 }
554 
555 struct usbd_pipe *
556 usbd_get_pipe0(struct usbd_device *dev)
557 {
558 
559 	return dev->ud_pipe0;
560 }
561 
562 static struct usbd_xfer *
563 usbd_alloc_xfer(struct usbd_device *dev, unsigned int nframes)
564 {
565 	struct usbd_xfer *xfer;
566 
567 	USBHIST_FUNC();
568 
569 	ASSERT_SLEEPABLE();
570 
571 	xfer = dev->ud_bus->ub_methods->ubm_allocx(dev->ud_bus, nframes);
572 	if (xfer == NULL)
573 		goto out;
574 	xfer->ux_bus = dev->ud_bus;
575 	callout_init(&xfer->ux_callout, CALLOUT_MPSAFE);
576 	callout_setfunc(&xfer->ux_callout, usbd_xfer_timeout, xfer);
577 	cv_init(&xfer->ux_cv, "usbxfer");
578 	usb_init_task(&xfer->ux_aborttask, usbd_xfer_timeout_task, xfer,
579 	    USB_TASKQ_MPSAFE);
580 
581 out:
582 	USBHIST_CALLARGS(usbdebug, "returns %#jx", (uintptr_t)xfer, 0, 0, 0);
583 
584 	return xfer;
585 }
586 
587 static usbd_status
588 usbd_free_xfer(struct usbd_xfer *xfer)
589 {
590 	USBHIST_FUNC();
591 	USBHIST_CALLARGS(usbdebug, "%#jx", (uintptr_t)xfer, 0, 0, 0);
592 
593 	if (xfer->ux_buf) {
594 		usbd_free_buffer(xfer);
595 	}
596 
597 	/* Wait for any straggling timeout to complete. */
598 	mutex_enter(xfer->ux_bus->ub_lock);
599 	xfer->ux_timeout_reset = false; /* do not resuscitate */
600 	callout_halt(&xfer->ux_callout, xfer->ux_bus->ub_lock);
601 	usb_rem_task_wait(xfer->ux_pipe->up_dev, &xfer->ux_aborttask,
602 	    USB_TASKQ_HC, xfer->ux_bus->ub_lock);
603 	mutex_exit(xfer->ux_bus->ub_lock);
604 
605 	cv_destroy(&xfer->ux_cv);
606 	xfer->ux_bus->ub_methods->ubm_freex(xfer->ux_bus, xfer);
607 	return USBD_NORMAL_COMPLETION;
608 }
609 
610 int
611 usbd_create_xfer(struct usbd_pipe *pipe, size_t len, unsigned int flags,
612     unsigned int nframes, struct usbd_xfer **xp)
613 {
614 	KASSERT(xp != NULL);
615 	void *buf = NULL;
616 
617 	struct usbd_xfer *xfer = usbd_alloc_xfer(pipe->up_dev, nframes);
618 	if (xfer == NULL)
619 		return ENOMEM;
620 
621 	xfer->ux_pipe = pipe;
622 	xfer->ux_flags = flags;
623 	xfer->ux_nframes = nframes;
624 	xfer->ux_methods = pipe->up_methods;
625 
626 	if (len) {
627 		buf = usbd_alloc_buffer(xfer, len);
628 		if (!buf) {
629 			usbd_free_xfer(xfer);
630 			return ENOMEM;
631 		}
632 	}
633 
634 	if (xfer->ux_methods->upm_init) {
635 		int err = xfer->ux_methods->upm_init(xfer);
636 		if (err) {
637 			usbd_free_xfer(xfer);
638 			return err;
639 		}
640 	}
641 
642 	*xp = xfer;
643 	SDT_PROBE5(usb, device, xfer, create,
644 	    xfer, pipe, len, flags, nframes);
645 	return 0;
646 }
647 
648 void
649 usbd_destroy_xfer(struct usbd_xfer *xfer)
650 {
651 
652 	SDT_PROBE1(usb, device, xfer, destroy,  xfer);
653 	if (xfer->ux_methods->upm_fini)
654 		xfer->ux_methods->upm_fini(xfer);
655 
656 	usbd_free_xfer(xfer);
657 }
658 
659 void
660 usbd_setup_xfer(struct usbd_xfer *xfer, void *priv, void *buffer,
661     uint32_t length, uint16_t flags, uint32_t timeout, usbd_callback callback)
662 {
663 	KASSERT(xfer->ux_pipe);
664 
665 	xfer->ux_priv = priv;
666 	xfer->ux_buffer = buffer;
667 	xfer->ux_length = length;
668 	xfer->ux_actlen = 0;
669 	xfer->ux_flags = flags;
670 	xfer->ux_timeout = timeout;
671 	xfer->ux_status = USBD_NOT_STARTED;
672 	xfer->ux_callback = callback;
673 	xfer->ux_rqflags &= ~URQ_REQUEST;
674 	xfer->ux_nframes = 0;
675 }
676 
677 void
678 usbd_setup_default_xfer(struct usbd_xfer *xfer, struct usbd_device *dev,
679     void *priv, uint32_t timeout, usb_device_request_t *req, void *buffer,
680     uint32_t length, uint16_t flags, usbd_callback callback)
681 {
682 	KASSERT(xfer->ux_pipe == dev->ud_pipe0);
683 
684 	xfer->ux_priv = priv;
685 	xfer->ux_buffer = buffer;
686 	xfer->ux_length = length;
687 	xfer->ux_actlen = 0;
688 	xfer->ux_flags = flags;
689 	xfer->ux_timeout = timeout;
690 	xfer->ux_status = USBD_NOT_STARTED;
691 	xfer->ux_callback = callback;
692 	xfer->ux_request = *req;
693 	xfer->ux_rqflags |= URQ_REQUEST;
694 	xfer->ux_nframes = 0;
695 }
696 
697 void
698 usbd_setup_isoc_xfer(struct usbd_xfer *xfer, void *priv, uint16_t *frlengths,
699     uint32_t nframes, uint16_t flags, usbd_callback callback)
700 {
701 	xfer->ux_priv = priv;
702 	xfer->ux_buffer = NULL;
703 	xfer->ux_length = 0;
704 	xfer->ux_actlen = 0;
705 	xfer->ux_flags = flags;
706 	xfer->ux_timeout = USBD_NO_TIMEOUT;
707 	xfer->ux_status = USBD_NOT_STARTED;
708 	xfer->ux_callback = callback;
709 	xfer->ux_rqflags &= ~URQ_REQUEST;
710 	xfer->ux_frlengths = frlengths;
711 	xfer->ux_nframes = nframes;
712 
713 	for (size_t i = 0; i < xfer->ux_nframes; i++)
714 		xfer->ux_length += xfer->ux_frlengths[i];
715 }
716 
717 void
718 usbd_get_xfer_status(struct usbd_xfer *xfer, void **priv,
719 		     void **buffer, uint32_t *count, usbd_status *status)
720 {
721 	if (priv != NULL)
722 		*priv = xfer->ux_priv;
723 	if (buffer != NULL)
724 		*buffer = xfer->ux_buffer;
725 	if (count != NULL)
726 		*count = xfer->ux_actlen;
727 	if (status != NULL)
728 		*status = xfer->ux_status;
729 }
730 
731 usb_config_descriptor_t *
732 usbd_get_config_descriptor(struct usbd_device *dev)
733 {
734 	KASSERT(dev != NULL);
735 
736 	return dev->ud_cdesc;
737 }
738 
739 usb_interface_descriptor_t *
740 usbd_get_interface_descriptor(struct usbd_interface *iface)
741 {
742 	KASSERT(iface != NULL);
743 
744 	return iface->ui_idesc;
745 }
746 
747 usb_device_descriptor_t *
748 usbd_get_device_descriptor(struct usbd_device *dev)
749 {
750 	KASSERT(dev != NULL);
751 
752 	return &dev->ud_ddesc;
753 }
754 
755 usb_endpoint_descriptor_t *
756 usbd_interface2endpoint_descriptor(struct usbd_interface *iface, uint8_t index)
757 {
758 
759 	if (index >= iface->ui_idesc->bNumEndpoints)
760 		return NULL;
761 	return iface->ui_endpoints[index].ue_edesc;
762 }
763 
764 /* Some drivers may wish to abort requests on the default pipe, *
765  * but there is no mechanism for getting a handle on it.        */
766 usbd_status
767 usbd_abort_default_pipe(struct usbd_device *device)
768 {
769 	return usbd_abort_pipe(device->ud_pipe0);
770 }
771 
772 usbd_status
773 usbd_abort_pipe(struct usbd_pipe *pipe)
774 {
775 	usbd_status err;
776 
777 	KASSERT(pipe != NULL);
778 
779 	usbd_lock_pipe(pipe);
780 	err = usbd_ar_pipe(pipe);
781 	usbd_unlock_pipe(pipe);
782 	return err;
783 }
784 
785 usbd_status
786 usbd_clear_endpoint_stall(struct usbd_pipe *pipe)
787 {
788 	struct usbd_device *dev = pipe->up_dev;
789 	usbd_status err;
790 
791 	USBHIST_FUNC(); USBHIST_CALLED(usbdebug);
792 	SDT_PROBE1(usb, device, pipe, clear__endpoint__stall,  pipe);
793 
794 	/*
795 	 * Clearing en endpoint stall resets the endpoint toggle, so
796 	 * do the same to the HC toggle.
797 	 */
798 	SDT_PROBE1(usb, device, pipe, clear__endpoint__toggle,  pipe);
799 	pipe->up_methods->upm_cleartoggle(pipe);
800 
801 	err = usbd_clear_endpoint_feature(dev,
802 	    pipe->up_endpoint->ue_edesc->bEndpointAddress, UF_ENDPOINT_HALT);
803 #if 0
804 XXX should we do this?
805 	if (!err) {
806 		pipe->state = USBD_PIPE_ACTIVE;
807 		/* XXX activate pipe */
808 	}
809 #endif
810 	return err;
811 }
812 
813 void
814 usbd_clear_endpoint_stall_task(void *arg)
815 {
816 	struct usbd_pipe *pipe = arg;
817 	struct usbd_device *dev = pipe->up_dev;
818 
819 	SDT_PROBE1(usb, device, pipe, clear__endpoint__stall,  pipe);
820 	SDT_PROBE1(usb, device, pipe, clear__endpoint__toggle,  pipe);
821 	pipe->up_methods->upm_cleartoggle(pipe);
822 
823 	(void)usbd_clear_endpoint_feature(dev,
824 	    pipe->up_endpoint->ue_edesc->bEndpointAddress, UF_ENDPOINT_HALT);
825 }
826 
827 void
828 usbd_clear_endpoint_stall_async(struct usbd_pipe *pipe)
829 {
830 	usb_add_task(pipe->up_dev, &pipe->up_async_task, USB_TASKQ_DRIVER);
831 }
832 
833 void
834 usbd_clear_endpoint_toggle(struct usbd_pipe *pipe)
835 {
836 
837 	SDT_PROBE1(usb, device, pipe, clear__endpoint__toggle,  pipe);
838 	pipe->up_methods->upm_cleartoggle(pipe);
839 }
840 
841 usbd_status
842 usbd_endpoint_count(struct usbd_interface *iface, uint8_t *count)
843 {
844 	KASSERT(iface != NULL);
845 	KASSERT(iface->ui_idesc != NULL);
846 
847 	*count = iface->ui_idesc->bNumEndpoints;
848 	return USBD_NORMAL_COMPLETION;
849 }
850 
851 usbd_status
852 usbd_interface_count(struct usbd_device *dev, uint8_t *count)
853 {
854 
855 	if (dev->ud_cdesc == NULL)
856 		return USBD_NOT_CONFIGURED;
857 	*count = dev->ud_cdesc->bNumInterface;
858 	return USBD_NORMAL_COMPLETION;
859 }
860 
861 void
862 usbd_interface2device_handle(struct usbd_interface *iface,
863 			     struct usbd_device **dev)
864 {
865 
866 	*dev = iface->ui_dev;
867 }
868 
869 usbd_status
870 usbd_device2interface_handle(struct usbd_device *dev,
871 			     uint8_t ifaceno, struct usbd_interface **iface)
872 {
873 
874 	if (dev->ud_cdesc == NULL)
875 		return USBD_NOT_CONFIGURED;
876 	if (ifaceno >= dev->ud_cdesc->bNumInterface)
877 		return USBD_INVAL;
878 	*iface = &dev->ud_ifaces[ifaceno];
879 	return USBD_NORMAL_COMPLETION;
880 }
881 
882 struct usbd_device *
883 usbd_pipe2device_handle(struct usbd_pipe *pipe)
884 {
885 	KASSERT(pipe != NULL);
886 
887 	return pipe->up_dev;
888 }
889 
890 /* XXXX use altno */
891 usbd_status
892 usbd_set_interface(struct usbd_interface *iface, int altidx)
893 {
894 	bool locked = false;
895 	usb_device_request_t req;
896 	usbd_status err;
897 
898 	USBHIST_FUNC();
899 	USBHIST_CALLARGS(usbdebug, "iface %#jx", (uintptr_t)iface, 0, 0, 0);
900 
901 	err = usbd_iface_lock(iface);
902 	if (err)
903 		goto out;
904 	locked = true;
905 
906 	err = usbd_fill_iface_data(iface->ui_dev, iface->ui_index, altidx);
907 	if (err)
908 		goto out;
909 
910 	req.bmRequestType = UT_WRITE_INTERFACE;
911 	req.bRequest = UR_SET_INTERFACE;
912 	USETW(req.wValue, iface->ui_idesc->bAlternateSetting);
913 	USETW(req.wIndex, iface->ui_idesc->bInterfaceNumber);
914 	USETW(req.wLength, 0);
915 	err = usbd_do_request(iface->ui_dev, &req, 0);
916 
917 out:	/* XXX back out iface data?  */
918 	if (locked)
919 		usbd_iface_unlock(iface);
920 	return err;
921 }
922 
923 int
924 usbd_get_no_alts(usb_config_descriptor_t *cdesc, int ifaceno)
925 {
926 	char *p = (char *)cdesc;
927 	char *end = p + UGETW(cdesc->wTotalLength);
928 	usb_interface_descriptor_t *d;
929 	int n;
930 
931 	for (n = 0; p < end; p += d->bLength) {
932 		d = (usb_interface_descriptor_t *)p;
933 		if (p + d->bLength <= end &&
934 		    d->bDescriptorType == UDESC_INTERFACE &&
935 		    d->bInterfaceNumber == ifaceno)
936 			n++;
937 	}
938 	return n;
939 }
940 
941 int
942 usbd_get_interface_altindex(struct usbd_interface *iface)
943 {
944 	return iface->ui_altindex;
945 }
946 
947 usbd_status
948 usbd_get_interface(struct usbd_interface *iface, uint8_t *aiface)
949 {
950 	usb_device_request_t req;
951 
952 	req.bmRequestType = UT_READ_INTERFACE;
953 	req.bRequest = UR_GET_INTERFACE;
954 	USETW(req.wValue, 0);
955 	USETW(req.wIndex, iface->ui_idesc->bInterfaceNumber);
956 	USETW(req.wLength, 1);
957 	return usbd_do_request(iface->ui_dev, &req, aiface);
958 }
959 
960 /*** Internal routines ***/
961 
962 /* Dequeue all pipe operations, called with bus lock held. */
963 Static usbd_status
964 usbd_ar_pipe(struct usbd_pipe *pipe)
965 {
966 	struct usbd_xfer *xfer;
967 
968 	USBHIST_FUNC();
969 	USBHIST_CALLARGS(usbdebug, "pipe = %#jx", (uintptr_t)pipe, 0, 0, 0);
970 	SDT_PROBE1(usb, device, pipe, abort__start,  pipe);
971 
972 	KASSERT(mutex_owned(pipe->up_dev->ud_bus->ub_lock));
973 
974 #ifdef USB_DEBUG
975 	if (usbdebug > 5)
976 		usbd_dump_queue(pipe);
977 #endif
978 	pipe->up_repeat = 0;
979 	pipe->up_running = 0;
980 	pipe->up_aborting = 1;
981 	while ((xfer = SIMPLEQ_FIRST(&pipe->up_queue)) != NULL) {
982 		USBHIST_LOG(usbdebug, "pipe = %#jx xfer = %#jx "
983 		    "(methods = %#jx)", (uintptr_t)pipe, (uintptr_t)xfer,
984 		    (uintptr_t)pipe->up_methods, 0);
985 		if (xfer->ux_status == USBD_NOT_STARTED) {
986 			SDT_PROBE1(usb, device, xfer, preabort,  xfer);
987 #ifdef DIAGNOSTIC
988 			xfer->ux_state = XFER_BUSY;
989 #endif
990 			SIMPLEQ_REMOVE_HEAD(&pipe->up_queue, ux_next);
991 		} else {
992 			/* Make the HC abort it (and invoke the callback). */
993 			SDT_PROBE1(usb, device, xfer, abort,  xfer);
994 			pipe->up_methods->upm_abort(xfer);
995 			while (pipe->up_callingxfer == xfer) {
996 				USBHIST_LOG(usbdebug, "wait for callback"
997 				    "pipe = %#jx xfer = %#jx",
998 				    (uintptr_t)pipe, (uintptr_t)xfer, 0, 0);
999 				cv_wait(&pipe->up_callingcv,
1000 				    pipe->up_dev->ud_bus->ub_lock);
1001 			}
1002 			/* XXX only for non-0 usbd_clear_endpoint_stall(pipe); */
1003 		}
1004 	}
1005 	pipe->up_aborting = 0;
1006 	SDT_PROBE1(usb, device, pipe, abort__done,  pipe);
1007 	return USBD_NORMAL_COMPLETION;
1008 }
1009 
1010 /* Called with USB lock held. */
1011 void
1012 usb_transfer_complete(struct usbd_xfer *xfer)
1013 {
1014 	struct usbd_pipe *pipe = xfer->ux_pipe;
1015 	struct usbd_bus *bus = pipe->up_dev->ud_bus;
1016 	int sync = xfer->ux_flags & USBD_SYNCHRONOUS;
1017 	int erred;
1018 	int polling = bus->ub_usepolling;
1019 	int repeat = pipe->up_repeat;
1020 
1021 	USBHIST_FUNC();
1022 	USBHIST_CALLARGS(usbdebug, "pipe = %#jx xfer = %#jx status = %jd "
1023 	    "actlen = %jd", (uintptr_t)pipe, (uintptr_t)xfer, xfer->ux_status,
1024 	    xfer->ux_actlen);
1025 
1026 	KASSERT(polling || mutex_owned(pipe->up_dev->ud_bus->ub_lock));
1027 	KASSERTMSG(xfer->ux_state == XFER_ONQU, "xfer %p state is %x", xfer,
1028 	    xfer->ux_state);
1029 	KASSERT(pipe != NULL);
1030 
1031 	/*
1032 	 * If device is known to miss out ack, then pretend that
1033 	 * output timeout is a success. Userland should handle
1034 	 * the logic to verify that the operation succeeded.
1035 	 */
1036 	if (pipe->up_dev->ud_quirks &&
1037 	    pipe->up_dev->ud_quirks->uq_flags & UQ_MISS_OUT_ACK &&
1038 	    xfer->ux_status == USBD_TIMEOUT &&
1039 	    !usbd_xfer_isread(xfer)) {
1040 		USBHIST_LOG(usbdebug, "Possible output ack miss for xfer %#jx: "
1041 		    "hiding write timeout to %jd.%jd for %ju bytes written",
1042 		    (uintptr_t)xfer, curlwp->l_proc->p_pid, curlwp->l_lid,
1043 		    xfer->ux_length);
1044 
1045 		xfer->ux_status = USBD_NORMAL_COMPLETION;
1046 		xfer->ux_actlen = xfer->ux_length;
1047 	}
1048 
1049 	erred = xfer->ux_status == USBD_CANCELLED ||
1050 	        xfer->ux_status == USBD_TIMEOUT;
1051 
1052 	if (!repeat) {
1053 		/* Remove request from queue. */
1054 
1055 		KASSERTMSG(!SIMPLEQ_EMPTY(&pipe->up_queue),
1056 		    "pipe %p is empty, but xfer %p wants to complete", pipe,
1057 		     xfer);
1058 		KASSERTMSG(xfer == SIMPLEQ_FIRST(&pipe->up_queue),
1059 		    "xfer %p is not start of queue (%p is at start)", xfer,
1060 		   SIMPLEQ_FIRST(&pipe->up_queue));
1061 
1062 #ifdef DIAGNOSTIC
1063 		xfer->ux_state = XFER_BUSY;
1064 #endif
1065 		SIMPLEQ_REMOVE_HEAD(&pipe->up_queue, ux_next);
1066 	}
1067 	USBHIST_LOG(usbdebug, "xfer %#jx: repeat %jd new head = %#jx",
1068 	    (uintptr_t)xfer, repeat, (uintptr_t)SIMPLEQ_FIRST(&pipe->up_queue),
1069 	    0);
1070 
1071 	/* Count completed transfers. */
1072 	++pipe->up_dev->ud_bus->ub_stats.uds_requests
1073 		[pipe->up_endpoint->ue_edesc->bmAttributes & UE_XFERTYPE];
1074 
1075 	xfer->ux_done = 1;
1076 	if (!xfer->ux_status && xfer->ux_actlen < xfer->ux_length &&
1077 	    !(xfer->ux_flags & USBD_SHORT_XFER_OK)) {
1078 		USBHIST_LOG(usbdebug, "short transfer %jd < %jd",
1079 		    xfer->ux_actlen, xfer->ux_length, 0, 0);
1080 		xfer->ux_status = USBD_SHORT_XFER;
1081 	}
1082 
1083 	USBHIST_LOG(usbdebug, "xfer %#jx doing done %#jx", (uintptr_t)xfer,
1084 	    (uintptr_t)pipe->up_methods->upm_done, 0, 0);
1085 	SDT_PROBE2(usb, device, xfer, done,  xfer, xfer->ux_status);
1086 	pipe->up_methods->upm_done(xfer);
1087 
1088 	if (xfer->ux_length != 0 && xfer->ux_buffer != xfer->ux_buf) {
1089 		KDASSERTMSG(xfer->ux_actlen <= xfer->ux_length,
1090 		    "actlen %d length %d",xfer->ux_actlen, xfer->ux_length);
1091 
1092 		/* Only if IN transfer */
1093 		if (usbd_xfer_isread(xfer)) {
1094 			memcpy(xfer->ux_buffer, xfer->ux_buf, xfer->ux_actlen);
1095 		}
1096 	}
1097 
1098 	USBHIST_LOG(usbdebug, "xfer %#jx doing callback %#jx status %jd",
1099 	    (uintptr_t)xfer, (uintptr_t)xfer->ux_callback, xfer->ux_status, 0);
1100 
1101 	if (xfer->ux_callback) {
1102 		if (!polling) {
1103 			KASSERT(pipe->up_callingxfer == NULL);
1104 			pipe->up_callingxfer = xfer;
1105 			mutex_exit(pipe->up_dev->ud_bus->ub_lock);
1106 			if (!(pipe->up_flags & USBD_MPSAFE))
1107 				KERNEL_LOCK(1, curlwp);
1108 		}
1109 
1110 		xfer->ux_callback(xfer, xfer->ux_priv, xfer->ux_status);
1111 
1112 		if (!polling) {
1113 			if (!(pipe->up_flags & USBD_MPSAFE))
1114 				KERNEL_UNLOCK_ONE(curlwp);
1115 			mutex_enter(pipe->up_dev->ud_bus->ub_lock);
1116 			KASSERT(pipe->up_callingxfer == xfer);
1117 			pipe->up_callingxfer = NULL;
1118 			cv_broadcast(&pipe->up_callingcv);
1119 		}
1120 	}
1121 
1122 	if (sync && !polling) {
1123 		USBHIST_LOG(usbdebug, "<- done xfer %#jx, wakeup",
1124 		    (uintptr_t)xfer, 0, 0, 0);
1125 		cv_broadcast(&xfer->ux_cv);
1126 	}
1127 
1128 	if (repeat) {
1129 		xfer->ux_actlen = 0;
1130 		xfer->ux_status = USBD_NOT_STARTED;
1131 	} else {
1132 		/* XXX should we stop the queue on all errors? */
1133 		if (erred && pipe->up_iface != NULL)	/* not control pipe */
1134 			pipe->up_running = 0;
1135 	}
1136 	if (pipe->up_running && pipe->up_serialise)
1137 		usbd_start_next(pipe);
1138 }
1139 
1140 /* Called with USB lock held. */
1141 usbd_status
1142 usb_insert_transfer(struct usbd_xfer *xfer)
1143 {
1144 	struct usbd_pipe *pipe = xfer->ux_pipe;
1145 	usbd_status err;
1146 
1147 	USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug,
1148 	    "xfer = %#jx pipe = %#jx running = %jd timeout = %jd",
1149 	    (uintptr_t)xfer, (uintptr_t)pipe,
1150 	    pipe->up_running, xfer->ux_timeout);
1151 
1152 	KASSERT(mutex_owned(pipe->up_dev->ud_bus->ub_lock));
1153 	KASSERTMSG(xfer->ux_state == XFER_BUSY, "xfer %p state is %x", xfer,
1154 	    xfer->ux_state);
1155 
1156 #ifdef DIAGNOSTIC
1157 	xfer->ux_state = XFER_ONQU;
1158 #endif
1159 	SIMPLEQ_INSERT_TAIL(&pipe->up_queue, xfer, ux_next);
1160 	if (pipe->up_running && pipe->up_serialise)
1161 		err = USBD_IN_PROGRESS;
1162 	else {
1163 		pipe->up_running = 1;
1164 		err = USBD_NORMAL_COMPLETION;
1165 	}
1166 	USBHIST_LOG(usbdebug, "<- done xfer %#jx, err %jd", (uintptr_t)xfer,
1167 	    err, 0, 0);
1168 	return err;
1169 }
1170 
1171 /* Called with USB lock held. */
1172 void
1173 usbd_start_next(struct usbd_pipe *pipe)
1174 {
1175 	struct usbd_xfer *xfer;
1176 	usbd_status err;
1177 
1178 	USBHIST_FUNC();
1179 
1180 	KASSERT(pipe != NULL);
1181 	KASSERT(pipe->up_methods != NULL);
1182 	KASSERT(pipe->up_methods->upm_start != NULL);
1183 	KASSERT(pipe->up_serialise == true);
1184 
1185 	int polling = pipe->up_dev->ud_bus->ub_usepolling;
1186 	KASSERT(polling || mutex_owned(pipe->up_dev->ud_bus->ub_lock));
1187 
1188 	/* Get next request in queue. */
1189 	xfer = SIMPLEQ_FIRST(&pipe->up_queue);
1190 	USBHIST_CALLARGS(usbdebug, "pipe = %#jx, xfer = %#jx", (uintptr_t)pipe,
1191 	    (uintptr_t)xfer, 0, 0);
1192 	if (xfer == NULL) {
1193 		pipe->up_running = 0;
1194 	} else {
1195 		if (!polling)
1196 			mutex_exit(pipe->up_dev->ud_bus->ub_lock);
1197 		SDT_PROBE2(usb, device, pipe, start,  pipe, xfer);
1198 		err = pipe->up_methods->upm_start(xfer);
1199 		if (!polling)
1200 			mutex_enter(pipe->up_dev->ud_bus->ub_lock);
1201 
1202 		if (err != USBD_IN_PROGRESS) {
1203 			USBHIST_LOG(usbdebug, "error = %jd", err, 0, 0, 0);
1204 			pipe->up_running = 0;
1205 			/* XXX do what? */
1206 		}
1207 	}
1208 
1209 	KASSERT(polling || mutex_owned(pipe->up_dev->ud_bus->ub_lock));
1210 }
1211 
1212 usbd_status
1213 usbd_do_request(struct usbd_device *dev, usb_device_request_t *req, void *data)
1214 {
1215 
1216 	return usbd_do_request_flags(dev, req, data, 0, 0,
1217 	    USBD_DEFAULT_TIMEOUT);
1218 }
1219 
1220 usbd_status
1221 usbd_do_request_flags(struct usbd_device *dev, usb_device_request_t *req,
1222     void *data, uint16_t flags, int *actlen, uint32_t timeout)
1223 {
1224 	size_t len = UGETW(req->wLength);
1225 
1226 	return usbd_do_request_len(dev, req, len, data, flags, actlen, timeout);
1227 }
1228 
1229 usbd_status
1230 usbd_do_request_len(struct usbd_device *dev, usb_device_request_t *req,
1231     size_t len, void *data, uint16_t flags, int *actlen, uint32_t timeout)
1232 {
1233 	struct usbd_xfer *xfer;
1234 	usbd_status err;
1235 
1236 	KASSERT(len >= UGETW(req->wLength));
1237 
1238 	USBHIST_FUNC();
1239 	USBHIST_CALLARGS(usbdebug, "dev=%#jx req=%jx flags=%jx len=%jx",
1240 	    (uintptr_t)dev, (uintptr_t)req, flags, len);
1241 
1242 	ASSERT_SLEEPABLE();
1243 
1244 	int error = usbd_create_xfer(dev->ud_pipe0, len, 0, 0, &xfer);
1245 	if (error)
1246 		return error;
1247 
1248 	usbd_setup_default_xfer(xfer, dev, 0, timeout, req, data,
1249 	    UGETW(req->wLength), flags, NULL);
1250 	KASSERT(xfer->ux_pipe == dev->ud_pipe0);
1251 	err = usbd_sync_transfer(xfer);
1252 #if defined(USB_DEBUG) || defined(DIAGNOSTIC)
1253 	if (xfer->ux_actlen > xfer->ux_length) {
1254 		USBHIST_LOG(usbdebug, "overrun addr = %jd type = 0x%02jx",
1255 		    dev->ud_addr, xfer->ux_request.bmRequestType, 0, 0);
1256 		USBHIST_LOG(usbdebug, "     req = 0x%02jx val = %jd "
1257 		    "index = %jd",
1258 		    xfer->ux_request.bRequest, UGETW(xfer->ux_request.wValue),
1259 		    UGETW(xfer->ux_request.wIndex), 0);
1260 		USBHIST_LOG(usbdebug, "     rlen = %jd length = %jd "
1261 		    "actlen = %jd",
1262 		    UGETW(xfer->ux_request.wLength),
1263 		    xfer->ux_length, xfer->ux_actlen, 0);
1264 	}
1265 #endif
1266 	if (actlen != NULL)
1267 		*actlen = xfer->ux_actlen;
1268 
1269 	usbd_destroy_xfer(xfer);
1270 
1271 	if (err) {
1272 		USBHIST_LOG(usbdebug, "returning err = %jd", err, 0, 0, 0);
1273 	}
1274 	return err;
1275 }
1276 
1277 static void
1278 usbd_request_async_cb(struct usbd_xfer *xfer, void *priv, usbd_status status)
1279 {
1280 	usbd_destroy_xfer(xfer);
1281 }
1282 
1283 /*
1284  * Execute a request without waiting for completion.
1285  * Can be used from interrupt context.
1286  */
1287 usbd_status
1288 usbd_request_async(struct usbd_device *dev, struct usbd_xfer *xfer,
1289     usb_device_request_t *req, void *priv, usbd_callback callback)
1290 {
1291 	usbd_status err;
1292 
1293 	if (callback == NULL)
1294 		callback = usbd_request_async_cb;
1295 
1296 	usbd_setup_default_xfer(xfer, dev, priv,
1297 	    USBD_DEFAULT_TIMEOUT, req, NULL, UGETW(req->wLength), 0,
1298 	    callback);
1299 	err = usbd_transfer(xfer);
1300 	if (err != USBD_IN_PROGRESS) {
1301 		usbd_destroy_xfer(xfer);
1302 		return (err);
1303 	}
1304 	return (USBD_NORMAL_COMPLETION);
1305 }
1306 
1307 const struct usbd_quirks *
1308 usbd_get_quirks(struct usbd_device *dev)
1309 {
1310 #ifdef DIAGNOSTIC
1311 	if (dev == NULL) {
1312 		printf("usbd_get_quirks: dev == NULL\n");
1313 		return 0;
1314 	}
1315 #endif
1316 	return dev->ud_quirks;
1317 }
1318 
1319 /* XXX do periodic free() of free list */
1320 
1321 /*
1322  * Called from keyboard driver when in polling mode.
1323  */
1324 void
1325 usbd_dopoll(struct usbd_interface *iface)
1326 {
1327 	iface->ui_dev->ud_bus->ub_methods->ubm_dopoll(iface->ui_dev->ud_bus);
1328 }
1329 
1330 /*
1331  * This is for keyboard driver as well, which only operates in polling
1332  * mode from the ask root, etc., prompt and from DDB.
1333  */
1334 void
1335 usbd_set_polling(struct usbd_device *dev, int on)
1336 {
1337 	if (on)
1338 		dev->ud_bus->ub_usepolling++;
1339 	else
1340 		dev->ud_bus->ub_usepolling--;
1341 
1342 	/* Kick the host controller when switching modes */
1343 	mutex_enter(dev->ud_bus->ub_lock);
1344 	dev->ud_bus->ub_methods->ubm_softint(dev->ud_bus);
1345 	mutex_exit(dev->ud_bus->ub_lock);
1346 }
1347 
1348 
1349 usb_endpoint_descriptor_t *
1350 usbd_get_endpoint_descriptor(struct usbd_interface *iface, uint8_t address)
1351 {
1352 	struct usbd_endpoint *ep;
1353 	int i;
1354 
1355 	for (i = 0; i < iface->ui_idesc->bNumEndpoints; i++) {
1356 		ep = &iface->ui_endpoints[i];
1357 		if (ep->ue_edesc->bEndpointAddress == address)
1358 			return iface->ui_endpoints[i].ue_edesc;
1359 	}
1360 	return NULL;
1361 }
1362 
1363 /*
1364  * usbd_ratecheck() can limit the number of error messages that occurs.
1365  * When a device is unplugged it may take up to 0.25s for the hub driver
1366  * to notice it.  If the driver continuously tries to do I/O operations
1367  * this can generate a large number of messages.
1368  */
1369 int
1370 usbd_ratecheck(struct timeval *last)
1371 {
1372 	static struct timeval errinterval = { 0, 250000 }; /* 0.25 s*/
1373 
1374 	return ratecheck(last, &errinterval);
1375 }
1376 
1377 /*
1378  * Search for a vendor/product pair in an array.  The item size is
1379  * given as an argument.
1380  */
1381 const struct usb_devno *
1382 usb_match_device(const struct usb_devno *tbl, u_int nentries, u_int sz,
1383 		 uint16_t vendor, uint16_t product)
1384 {
1385 	while (nentries-- > 0) {
1386 		uint16_t tproduct = tbl->ud_product;
1387 		if (tbl->ud_vendor == vendor &&
1388 		    (tproduct == product || tproduct == USB_PRODUCT_ANY))
1389 			return tbl;
1390 		tbl = (const struct usb_devno *)((const char *)tbl + sz);
1391 	}
1392 	return NULL;
1393 }
1394 
1395 usbd_status
1396 usbd_get_string(struct usbd_device *dev, int si, char *buf)
1397 {
1398 	return usbd_get_string0(dev, si, buf, 1);
1399 }
1400 
1401 usbd_status
1402 usbd_get_string0(struct usbd_device *dev, int si, char *buf, int unicode)
1403 {
1404 	int swap = dev->ud_quirks->uq_flags & UQ_SWAP_UNICODE;
1405 	usb_string_descriptor_t us;
1406 	char *s;
1407 	int i, n;
1408 	uint16_t c;
1409 	usbd_status err;
1410 	int size;
1411 
1412 	USBHIST_FUNC(); USBHIST_CALLED(usbdebug);
1413 
1414 	buf[0] = '\0';
1415 	if (si == 0)
1416 		return USBD_INVAL;
1417 	if (dev->ud_quirks->uq_flags & UQ_NO_STRINGS)
1418 		return USBD_STALLED;
1419 	if (dev->ud_langid == USBD_NOLANG) {
1420 		/* Set up default language */
1421 		err = usbd_get_string_desc(dev, USB_LANGUAGE_TABLE, 0, &us,
1422 		    &size);
1423 		if (err || size < 4) {
1424 			USBHIST_LOG(usbdebug, "getting lang failed, using 0",
1425 			    0, 0, 0, 0);
1426 			dev->ud_langid = 0; /* Well, just pick something then */
1427 		} else {
1428 			/* Pick the first language as the default. */
1429 			dev->ud_langid = UGETW(us.bString[0]);
1430 		}
1431 	}
1432 	err = usbd_get_string_desc(dev, si, dev->ud_langid, &us, &size);
1433 	if (err)
1434 		return err;
1435 	s = buf;
1436 	n = size / 2 - 1;
1437 	if (unicode) {
1438 		for (i = 0; i < n; i++) {
1439 			c = UGETW(us.bString[i]);
1440 			if (swap)
1441 				c = (c >> 8) | (c << 8);
1442 			s += wput_utf8(s, 3, c);
1443 		}
1444 		*s++ = 0;
1445 	}
1446 #ifdef COMPAT_30
1447 	else {
1448 		for (i = 0; i < n; i++) {
1449 			c = UGETW(us.bString[i]);
1450 			if (swap)
1451 				c = (c >> 8) | (c << 8);
1452 			*s++ = (c < 0x80) ? c : '?';
1453 		}
1454 		*s++ = 0;
1455 	}
1456 #endif
1457 	return USBD_NORMAL_COMPLETION;
1458 }
1459 
1460 /*
1461  * usbd_xfer_trycomplete(xfer)
1462  *
1463  *	Try to claim xfer for completion.  Return true if successful,
1464  *	false if the xfer has been synchronously aborted or has timed
1465  *	out.
1466  *
1467  *	If this returns true, caller is responsible for setting
1468  *	xfer->ux_status and calling usb_transfer_complete.  To be used
1469  *	in a host controller interrupt handler.
1470  *
1471  *	Caller must either hold the bus lock or have the bus in polling
1472  *	mode.
1473  */
1474 bool
1475 usbd_xfer_trycomplete(struct usbd_xfer *xfer)
1476 {
1477 	struct usbd_bus *bus __diagused = xfer->ux_bus;
1478 
1479 	KASSERT(bus->ub_usepolling || mutex_owned(bus->ub_lock));
1480 
1481 	/*
1482 	 * If software has completed it, either by synchronous abort or
1483 	 * by timeout, too late.
1484 	 */
1485 	if (xfer->ux_status != USBD_IN_PROGRESS)
1486 		return false;
1487 
1488 	/*
1489 	 * We are completing the xfer.  Cancel the timeout if we can,
1490 	 * but only asynchronously.  See usbd_xfer_cancel_timeout_async
1491 	 * for why we need not wait for the callout or task here.
1492 	 */
1493 	usbd_xfer_cancel_timeout_async(xfer);
1494 
1495 	/* Success!  Note: Caller must set xfer->ux_status afterwar.  */
1496 	return true;
1497 }
1498 
1499 /*
1500  * usbd_xfer_abort(xfer)
1501  *
1502  *	Try to claim xfer to abort.  If successful, mark it completed
1503  *	with USBD_CANCELLED and call the bus-specific method to abort
1504  *	at the hardware level.
1505  *
1506  *	To be called in thread context from struct
1507  *	usbd_pipe_methods::upm_abort.
1508  *
1509  *	Caller must hold the bus lock.
1510  */
1511 void
1512 usbd_xfer_abort(struct usbd_xfer *xfer)
1513 {
1514 	struct usbd_bus *bus = xfer->ux_bus;
1515 
1516 	KASSERT(mutex_owned(bus->ub_lock));
1517 
1518 	/*
1519 	 * If host controller interrupt or timer interrupt has
1520 	 * completed it, too late.  But the xfer cannot be
1521 	 * cancelled already -- only one caller can synchronously
1522 	 * abort.
1523 	 */
1524 	KASSERT(xfer->ux_status != USBD_CANCELLED);
1525 	if (xfer->ux_status != USBD_IN_PROGRESS)
1526 		return;
1527 
1528 	/*
1529 	 * Cancel the timeout if we can, but only asynchronously; see
1530 	 * usbd_xfer_cancel_timeout_async for why we need not wait for
1531 	 * the callout or task here.
1532 	 */
1533 	usbd_xfer_cancel_timeout_async(xfer);
1534 
1535 	/*
1536 	 * We beat everyone else.  Claim the status as cancelled and do
1537 	 * the bus-specific dance to abort the hardware.
1538 	 */
1539 	xfer->ux_status = USBD_CANCELLED;
1540 	bus->ub_methods->ubm_abortx(xfer);
1541 }
1542 
1543 /*
1544  * usbd_xfer_timeout(xfer)
1545  *
1546  *	Called at IPL_SOFTCLOCK when too much time has elapsed waiting
1547  *	for xfer to complete.  Since we can't abort the xfer at
1548  *	IPL_SOFTCLOCK, defer to a usb_task to run it in thread context,
1549  *	unless the xfer has completed or aborted concurrently -- and if
1550  *	the xfer has also been resubmitted, take care of rescheduling
1551  *	the callout.
1552  */
1553 static void
1554 usbd_xfer_timeout(void *cookie)
1555 {
1556 	struct usbd_xfer *xfer = cookie;
1557 	struct usbd_bus *bus = xfer->ux_bus;
1558 	struct usbd_device *dev = xfer->ux_pipe->up_dev;
1559 
1560 	/* Acquire the lock so we can transition the timeout state.  */
1561 	mutex_enter(bus->ub_lock);
1562 
1563 	/*
1564 	 * Use usbd_xfer_probe_timeout to check whether the timeout is
1565 	 * still valid, or to reschedule the callout if necessary.  If
1566 	 * it is still valid, schedule the task.
1567 	 */
1568 	if (usbd_xfer_probe_timeout(xfer))
1569 		usb_add_task(dev, &xfer->ux_aborttask, USB_TASKQ_HC);
1570 
1571 	/*
1572 	 * Notify usbd_xfer_cancel_timeout_async that we may have
1573 	 * scheduled the task.  This causes callout_invoking to return
1574 	 * false in usbd_xfer_cancel_timeout_async so that it can tell
1575 	 * which stage in the callout->task->abort process we're at.
1576 	 */
1577 	callout_ack(&xfer->ux_callout);
1578 
1579 	/* All done -- release the lock.  */
1580 	mutex_exit(bus->ub_lock);
1581 }
1582 
1583 /*
1584  * usbd_xfer_timeout_task(xfer)
1585  *
1586  *	Called in thread context when too much time has elapsed waiting
1587  *	for xfer to complete.  Abort the xfer with USBD_TIMEOUT, unless
1588  *	it has completed or aborted concurrently -- and if the xfer has
1589  *	also been resubmitted, take care of rescheduling the callout.
1590  */
1591 static void
1592 usbd_xfer_timeout_task(void *cookie)
1593 {
1594 	struct usbd_xfer *xfer = cookie;
1595 	struct usbd_bus *bus = xfer->ux_bus;
1596 
1597 	/* Acquire the lock so we can transition the timeout state.  */
1598 	mutex_enter(bus->ub_lock);
1599 
1600 	/*
1601 	 * Use usbd_xfer_probe_timeout to check whether the timeout is
1602 	 * still valid, or to reschedule the callout if necessary.  If
1603 	 * it is not valid -- the timeout has been asynchronously
1604 	 * cancelled, or the xfer has already been resubmitted -- then
1605 	 * we're done here.
1606 	 */
1607 	if (!usbd_xfer_probe_timeout(xfer))
1608 		goto out;
1609 
1610 	/*
1611 	 * May have completed or been aborted, but we're the only one
1612 	 * who can time it out.  If it has completed or been aborted,
1613 	 * no need to timeout.
1614 	 */
1615 	KASSERT(xfer->ux_status != USBD_TIMEOUT);
1616 	if (xfer->ux_status != USBD_IN_PROGRESS)
1617 		goto out;
1618 
1619 	/*
1620 	 * We beat everyone else.  Claim the status as timed out and do
1621 	 * the bus-specific dance to abort the hardware.
1622 	 */
1623 	xfer->ux_status = USBD_TIMEOUT;
1624 	bus->ub_methods->ubm_abortx(xfer);
1625 
1626 out:	/* All done -- release the lock.  */
1627 	mutex_exit(bus->ub_lock);
1628 }
1629 
1630 /*
1631  * usbd_xfer_probe_timeout(xfer)
1632  *
1633  *	Probe the status of xfer's timeout.  Acknowledge and process a
1634  *	request to reschedule.  Return true if the timeout is still
1635  *	valid and the caller should take further action (queueing a
1636  *	task or aborting the xfer), false if it must stop here.
1637  */
1638 static bool
1639 usbd_xfer_probe_timeout(struct usbd_xfer *xfer)
1640 {
1641 	struct usbd_bus *bus = xfer->ux_bus;
1642 	bool valid;
1643 
1644 	KASSERT(bus->ub_usepolling || mutex_owned(bus->ub_lock));
1645 
1646 	/* The timeout must be set.  */
1647 	KASSERT(xfer->ux_timeout_set);
1648 
1649 	/*
1650 	 * Neither callout nor task may be pending; they execute
1651 	 * alternately in lock step.
1652 	 */
1653 	KASSERT(!callout_pending(&xfer->ux_callout));
1654 	KASSERT(!usb_task_pending(xfer->ux_pipe->up_dev, &xfer->ux_aborttask));
1655 
1656 	/* There are a few cases... */
1657 	if (bus->ub_methods->ubm_dying(bus)) {
1658 		/* Host controller dying.  Drop it all on the floor.  */
1659 		xfer->ux_timeout_set = false;
1660 		xfer->ux_timeout_reset = false;
1661 		valid = false;
1662 	} else if (xfer->ux_timeout_reset) {
1663 		/*
1664 		 * The xfer completed _and_ got resubmitted while we
1665 		 * waited for the lock.  Acknowledge the request to
1666 		 * reschedule, and reschedule it if there is a timeout
1667 		 * and the bus is not polling.
1668 		 */
1669 		xfer->ux_timeout_reset = false;
1670 		if (xfer->ux_timeout && !bus->ub_usepolling) {
1671 			KASSERT(xfer->ux_timeout_set);
1672 			callout_schedule(&xfer->ux_callout,
1673 			    mstohz(xfer->ux_timeout));
1674 		} else {
1675 			/* No more callout or task scheduled.  */
1676 			xfer->ux_timeout_set = false;
1677 		}
1678 		valid = false;
1679 	} else if (xfer->ux_status != USBD_IN_PROGRESS) {
1680 		/*
1681 		 * The xfer has completed by hardware completion or by
1682 		 * software abort, and has not been resubmitted, so the
1683 		 * timeout must be unset, and is no longer valid for
1684 		 * the caller.
1685 		 */
1686 		xfer->ux_timeout_set = false;
1687 		valid = false;
1688 	} else {
1689 		/*
1690 		 * The xfer has not yet completed, so the timeout is
1691 		 * valid.
1692 		 */
1693 		valid = true;
1694 	}
1695 
1696 	/* Any reset must have been processed.  */
1697 	KASSERT(!xfer->ux_timeout_reset);
1698 
1699 	/*
1700 	 * Either we claim the timeout is set, or the callout is idle.
1701 	 * If the timeout is still set, we may be handing off to the
1702 	 * task instead, so this is an if but not an iff.
1703 	 */
1704 	KASSERT(xfer->ux_timeout_set || !callout_pending(&xfer->ux_callout));
1705 
1706 	/*
1707 	 * The task must be idle now.
1708 	 *
1709 	 * - If the caller is the callout, _and_ the timeout is still
1710 	 *   valid, the caller will schedule it, but it hasn't been
1711 	 *   scheduled yet.  (If the timeout is not valid, the task
1712 	 *   should not be scheduled.)
1713 	 *
1714 	 * - If the caller is the task, it cannot be scheduled again
1715 	 *   until the callout runs again, which won't happen until we
1716 	 *   next release the lock.
1717 	 */
1718 	KASSERT(!usb_task_pending(xfer->ux_pipe->up_dev, &xfer->ux_aborttask));
1719 
1720 	KASSERT(bus->ub_usepolling || mutex_owned(bus->ub_lock));
1721 
1722 	return valid;
1723 }
1724 
1725 /*
1726  * usbd_xfer_schedule_timeout(xfer)
1727  *
1728  *	Ensure that xfer has a timeout.  If the callout is already
1729  *	queued or the task is already running, request that they
1730  *	reschedule the callout.  If not, and if we're not polling,
1731  *	schedule the callout anew.
1732  *
1733  *	To be called in thread context from struct
1734  *	usbd_pipe_methods::upm_start.
1735  */
1736 void
1737 usbd_xfer_schedule_timeout(struct usbd_xfer *xfer)
1738 {
1739 	struct usbd_bus *bus = xfer->ux_bus;
1740 
1741 	KASSERT(bus->ub_usepolling || mutex_owned(bus->ub_lock));
1742 
1743 	if (xfer->ux_timeout_set) {
1744 		/*
1745 		 * Callout or task has fired from a prior completed
1746 		 * xfer but has not yet noticed that the xfer is done.
1747 		 * Ask it to reschedule itself to ux_timeout.
1748 		 */
1749 		xfer->ux_timeout_reset = true;
1750 	} else if (xfer->ux_timeout && !bus->ub_usepolling) {
1751 		/* Callout is not scheduled.  Schedule it.  */
1752 		KASSERT(!callout_pending(&xfer->ux_callout));
1753 		callout_schedule(&xfer->ux_callout, mstohz(xfer->ux_timeout));
1754 		xfer->ux_timeout_set = true;
1755 	}
1756 
1757 	KASSERT(bus->ub_usepolling || mutex_owned(bus->ub_lock));
1758 }
1759 
1760 /*
1761  * usbd_xfer_cancel_timeout_async(xfer)
1762  *
1763  *	Cancel the callout and the task of xfer, which have not yet run
1764  *	to completion, but don't wait for the callout or task to finish
1765  *	running.
1766  *
1767  *	If they have already fired, at worst they are waiting for the
1768  *	bus lock.  They will see that the xfer is no longer in progress
1769  *	and give up, or they will see that the xfer has been
1770  *	resubmitted with a new timeout and reschedule the callout.
1771  *
1772  *	If a resubmitted request completed so fast that the callout
1773  *	didn't have time to process a timer reset, just cancel the
1774  *	timer reset.
1775  */
1776 static void
1777 usbd_xfer_cancel_timeout_async(struct usbd_xfer *xfer)
1778 {
1779 	struct usbd_bus *bus __diagused = xfer->ux_bus;
1780 
1781 	KASSERT(bus->ub_usepolling || mutex_owned(bus->ub_lock));
1782 
1783 	/*
1784 	 * If the timer wasn't running anyway, forget about it.  This
1785 	 * can happen if we are completing an isochronous transfer
1786 	 * which doesn't use the same timeout logic.
1787 	 */
1788 	if (!xfer->ux_timeout_set)
1789 		return;
1790 
1791 	xfer->ux_timeout_reset = false;
1792 	if (!callout_stop(&xfer->ux_callout)) {
1793 		/*
1794 		 * We stopped the callout before it ran.  The timeout
1795 		 * is no longer set.
1796 		 */
1797 		xfer->ux_timeout_set = false;
1798 	} else if (callout_invoking(&xfer->ux_callout)) {
1799 		/*
1800 		 * The callout has begun to run but it has not yet
1801 		 * acquired the lock and called callout_ack.  The task
1802 		 * cannot be queued yet, and the callout cannot have
1803 		 * been rescheduled yet.
1804 		 *
1805 		 * By the time the callout acquires the lock, we will
1806 		 * have transitioned from USBD_IN_PROGRESS to a
1807 		 * completed status, and possibly also resubmitted the
1808 		 * xfer and set xfer->ux_timeout_reset = true.  In both
1809 		 * cases, the callout will DTRT, so no further action
1810 		 * is needed here.
1811 		 */
1812 	} else if (usb_rem_task(xfer->ux_pipe->up_dev, &xfer->ux_aborttask)) {
1813 		/*
1814 		 * The callout had fired and scheduled the task, but we
1815 		 * stopped the task before it could run.  The timeout
1816 		 * is therefore no longer set -- the next resubmission
1817 		 * of the xfer must schedule a new timeout.
1818 		 *
1819 		 * The callout should not be pending at this point:
1820 		 * it is scheduled only under the lock, and only when
1821 		 * xfer->ux_timeout_set is false, or by the callout or
1822 		 * task itself when xfer->ux_timeout_reset is true.
1823 		 */
1824 		xfer->ux_timeout_set = false;
1825 	}
1826 
1827 	/*
1828 	 * The callout cannot be scheduled and the task cannot be
1829 	 * queued at this point.  Either we cancelled them, or they are
1830 	 * already running and waiting for the bus lock.
1831 	 */
1832 	KASSERT(!callout_pending(&xfer->ux_callout));
1833 	KASSERT(!usb_task_pending(xfer->ux_pipe->up_dev, &xfer->ux_aborttask));
1834 
1835 	KASSERT(bus->ub_usepolling || mutex_owned(bus->ub_lock));
1836 }
1837