xref: /openbmc/qemu/hw/usb/core.c (revision 57a33d89)
1 /*
2  * QEMU USB emulation
3  *
4  * Copyright (c) 2005 Fabrice Bellard
5  *
6  * 2008 Generic packet handler rewrite by Max Krasnyansky
7  *
8  * Permission is hereby granted, free of charge, to any person obtaining a copy
9  * of this software and associated documentation files (the "Software"), to deal
10  * in the Software without restriction, including without limitation the rights
11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12  * copies of the Software, and to permit persons to whom the Software is
13  * furnished to do so, subject to the following conditions:
14  *
15  * The above copyright notice and this permission notice shall be included in
16  * all copies or substantial portions of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24  * THE SOFTWARE.
25  */
26 #include "qemu-common.h"
27 #include "hw/usb.h"
28 #include "iov.h"
29 #include "trace.h"
30 
31 void usb_attach(USBPort *port)
32 {
33     USBDevice *dev = port->dev;
34 
35     assert(dev != NULL);
36     assert(dev->attached);
37     assert(dev->state == USB_STATE_NOTATTACHED);
38     port->ops->attach(port);
39     dev->state = USB_STATE_ATTACHED;
40     usb_device_handle_attach(dev);
41 }
42 
43 void usb_detach(USBPort *port)
44 {
45     USBDevice *dev = port->dev;
46 
47     assert(dev != NULL);
48     assert(dev->state != USB_STATE_NOTATTACHED);
49     port->ops->detach(port);
50     dev->state = USB_STATE_NOTATTACHED;
51 }
52 
53 void usb_port_reset(USBPort *port)
54 {
55     USBDevice *dev = port->dev;
56 
57     assert(dev != NULL);
58     usb_detach(port);
59     usb_attach(port);
60     usb_device_reset(dev);
61 }
62 
63 void usb_device_reset(USBDevice *dev)
64 {
65     if (dev == NULL || !dev->attached) {
66         return;
67     }
68     dev->remote_wakeup = 0;
69     dev->addr = 0;
70     dev->state = USB_STATE_DEFAULT;
71     usb_device_handle_reset(dev);
72 }
73 
74 void usb_wakeup(USBEndpoint *ep)
75 {
76     USBDevice *dev = ep->dev;
77     USBBus *bus = usb_bus_from_device(dev);
78 
79     if (dev->remote_wakeup && dev->port && dev->port->ops->wakeup) {
80         dev->port->ops->wakeup(dev->port);
81     }
82     if (bus->ops->wakeup_endpoint) {
83         bus->ops->wakeup_endpoint(bus, ep);
84     }
85 }
86 
87 /**********************/
88 
89 /* generic USB device helpers (you are not forced to use them when
90    writing your USB device driver, but they help handling the
91    protocol)
92 */
93 
94 #define SETUP_STATE_IDLE  0
95 #define SETUP_STATE_SETUP 1
96 #define SETUP_STATE_DATA  2
97 #define SETUP_STATE_ACK   3
98 #define SETUP_STATE_PARAM 4
99 
100 static int do_token_setup(USBDevice *s, USBPacket *p)
101 {
102     int request, value, index;
103     int ret = 0;
104 
105     if (p->iov.size != 8) {
106         return USB_RET_STALL;
107     }
108 
109     usb_packet_copy(p, s->setup_buf, p->iov.size);
110     s->setup_len   = (s->setup_buf[7] << 8) | s->setup_buf[6];
111     s->setup_index = 0;
112 
113     request = (s->setup_buf[0] << 8) | s->setup_buf[1];
114     value   = (s->setup_buf[3] << 8) | s->setup_buf[2];
115     index   = (s->setup_buf[5] << 8) | s->setup_buf[4];
116 
117     if (s->setup_buf[0] & USB_DIR_IN) {
118         ret = usb_device_handle_control(s, p, request, value, index,
119                                         s->setup_len, s->data_buf);
120         if (ret == USB_RET_ASYNC) {
121              s->setup_state = SETUP_STATE_SETUP;
122              return USB_RET_ASYNC;
123         }
124         if (ret < 0)
125             return ret;
126 
127         if (ret < s->setup_len)
128             s->setup_len = ret;
129         s->setup_state = SETUP_STATE_DATA;
130     } else {
131         if (s->setup_len > sizeof(s->data_buf)) {
132             fprintf(stderr,
133                 "usb_generic_handle_packet: ctrl buffer too small (%d > %zu)\n",
134                 s->setup_len, sizeof(s->data_buf));
135             return USB_RET_STALL;
136         }
137         if (s->setup_len == 0)
138             s->setup_state = SETUP_STATE_ACK;
139         else
140             s->setup_state = SETUP_STATE_DATA;
141     }
142 
143     return ret;
144 }
145 
146 static int do_token_in(USBDevice *s, USBPacket *p)
147 {
148     int request, value, index;
149     int ret = 0;
150 
151     assert(p->ep->nr == 0);
152 
153     request = (s->setup_buf[0] << 8) | s->setup_buf[1];
154     value   = (s->setup_buf[3] << 8) | s->setup_buf[2];
155     index   = (s->setup_buf[5] << 8) | s->setup_buf[4];
156 
157     switch(s->setup_state) {
158     case SETUP_STATE_ACK:
159         if (!(s->setup_buf[0] & USB_DIR_IN)) {
160             ret = usb_device_handle_control(s, p, request, value, index,
161                                             s->setup_len, s->data_buf);
162             if (ret == USB_RET_ASYNC) {
163                 return USB_RET_ASYNC;
164             }
165             s->setup_state = SETUP_STATE_IDLE;
166             if (ret > 0)
167                 return 0;
168             return ret;
169         }
170 
171         /* return 0 byte */
172         return 0;
173 
174     case SETUP_STATE_DATA:
175         if (s->setup_buf[0] & USB_DIR_IN) {
176             int len = s->setup_len - s->setup_index;
177             if (len > p->iov.size) {
178                 len = p->iov.size;
179             }
180             usb_packet_copy(p, s->data_buf + s->setup_index, len);
181             s->setup_index += len;
182             if (s->setup_index >= s->setup_len)
183                 s->setup_state = SETUP_STATE_ACK;
184             return len;
185         }
186 
187         s->setup_state = SETUP_STATE_IDLE;
188         return USB_RET_STALL;
189 
190     default:
191         return USB_RET_STALL;
192     }
193 }
194 
195 static int do_token_out(USBDevice *s, USBPacket *p)
196 {
197     assert(p->ep->nr == 0);
198 
199     switch(s->setup_state) {
200     case SETUP_STATE_ACK:
201         if (s->setup_buf[0] & USB_DIR_IN) {
202             s->setup_state = SETUP_STATE_IDLE;
203             /* transfer OK */
204         } else {
205             /* ignore additional output */
206         }
207         return 0;
208 
209     case SETUP_STATE_DATA:
210         if (!(s->setup_buf[0] & USB_DIR_IN)) {
211             int len = s->setup_len - s->setup_index;
212             if (len > p->iov.size) {
213                 len = p->iov.size;
214             }
215             usb_packet_copy(p, s->data_buf + s->setup_index, len);
216             s->setup_index += len;
217             if (s->setup_index >= s->setup_len)
218                 s->setup_state = SETUP_STATE_ACK;
219             return len;
220         }
221 
222         s->setup_state = SETUP_STATE_IDLE;
223         return USB_RET_STALL;
224 
225     default:
226         return USB_RET_STALL;
227     }
228 }
229 
230 static int do_parameter(USBDevice *s, USBPacket *p)
231 {
232     int request, value, index;
233     int i, ret = 0;
234 
235     for (i = 0; i < 8; i++) {
236         s->setup_buf[i] = p->parameter >> (i*8);
237     }
238 
239     s->setup_state = SETUP_STATE_PARAM;
240     s->setup_len   = (s->setup_buf[7] << 8) | s->setup_buf[6];
241     s->setup_index = 0;
242 
243     request = (s->setup_buf[0] << 8) | s->setup_buf[1];
244     value   = (s->setup_buf[3] << 8) | s->setup_buf[2];
245     index   = (s->setup_buf[5] << 8) | s->setup_buf[4];
246 
247     if (s->setup_len > sizeof(s->data_buf)) {
248         fprintf(stderr,
249                 "usb_generic_handle_packet: ctrl buffer too small (%d > %zu)\n",
250                 s->setup_len, sizeof(s->data_buf));
251         return USB_RET_STALL;
252     }
253 
254     if (p->pid == USB_TOKEN_OUT) {
255         usb_packet_copy(p, s->data_buf, s->setup_len);
256     }
257 
258     ret = usb_device_handle_control(s, p, request, value, index,
259                                     s->setup_len, s->data_buf);
260     if (ret < 0) {
261         return ret;
262     }
263 
264     if (ret < s->setup_len) {
265         s->setup_len = ret;
266     }
267     if (p->pid == USB_TOKEN_IN) {
268         usb_packet_copy(p, s->data_buf, s->setup_len);
269     }
270 
271     return ret;
272 }
273 
274 /* ctrl complete function for devices which use usb_generic_handle_packet and
275    may return USB_RET_ASYNC from their handle_control callback. Device code
276    which does this *must* call this function instead of the normal
277    usb_packet_complete to complete their async control packets. */
278 void usb_generic_async_ctrl_complete(USBDevice *s, USBPacket *p)
279 {
280     if (p->result < 0) {
281         s->setup_state = SETUP_STATE_IDLE;
282     }
283 
284     switch (s->setup_state) {
285     case SETUP_STATE_SETUP:
286         if (p->result < s->setup_len) {
287             s->setup_len = p->result;
288         }
289         s->setup_state = SETUP_STATE_DATA;
290         p->result = 8;
291         break;
292 
293     case SETUP_STATE_ACK:
294         s->setup_state = SETUP_STATE_IDLE;
295         p->result = 0;
296         break;
297 
298     case SETUP_STATE_PARAM:
299         if (p->result < s->setup_len) {
300             s->setup_len = p->result;
301         }
302         if (p->pid == USB_TOKEN_IN) {
303             p->result = 0;
304             usb_packet_copy(p, s->data_buf, s->setup_len);
305         }
306         break;
307 
308     default:
309         break;
310     }
311     usb_packet_complete(s, p);
312 }
313 
314 /* XXX: fix overflow */
315 int set_usb_string(uint8_t *buf, const char *str)
316 {
317     int len, i;
318     uint8_t *q;
319 
320     q = buf;
321     len = strlen(str);
322     *q++ = 2 * len + 2;
323     *q++ = 3;
324     for(i = 0; i < len; i++) {
325         *q++ = str[i];
326         *q++ = 0;
327     }
328     return q - buf;
329 }
330 
331 USBDevice *usb_find_device(USBPort *port, uint8_t addr)
332 {
333     USBDevice *dev = port->dev;
334 
335     if (dev == NULL || !dev->attached || dev->state != USB_STATE_DEFAULT) {
336         return NULL;
337     }
338     if (dev->addr == addr) {
339         return dev;
340     }
341     return usb_device_find_device(dev, addr);
342 }
343 
344 static int usb_process_one(USBPacket *p)
345 {
346     USBDevice *dev = p->ep->dev;
347 
348     if (p->ep->nr == 0) {
349         /* control pipe */
350         if (p->parameter) {
351             return do_parameter(dev, p);
352         }
353         switch (p->pid) {
354         case USB_TOKEN_SETUP:
355             return do_token_setup(dev, p);
356         case USB_TOKEN_IN:
357             return do_token_in(dev, p);
358         case USB_TOKEN_OUT:
359             return do_token_out(dev, p);
360         default:
361             return USB_RET_STALL;
362         }
363     } else {
364         /* data pipe */
365         return usb_device_handle_data(dev, p);
366     }
367 }
368 
369 /* Hand over a packet to a device for processing.  Return value
370    USB_RET_ASYNC indicates the processing isn't finished yet, the
371    driver will call usb_packet_complete() when done processing it. */
372 int usb_handle_packet(USBDevice *dev, USBPacket *p)
373 {
374     int ret;
375 
376     if (dev == NULL) {
377         return USB_RET_NODEV;
378     }
379     assert(dev == p->ep->dev);
380     assert(dev->state == USB_STATE_DEFAULT);
381     usb_packet_check_state(p, USB_PACKET_SETUP);
382     assert(p->ep != NULL);
383 
384     if (QTAILQ_EMPTY(&p->ep->queue) || p->ep->pipeline) {
385         ret = usb_process_one(p);
386         if (ret == USB_RET_ASYNC) {
387             usb_packet_set_state(p, USB_PACKET_ASYNC);
388             QTAILQ_INSERT_TAIL(&p->ep->queue, p, queue);
389         } else {
390             p->result = ret;
391             usb_packet_set_state(p, USB_PACKET_COMPLETE);
392         }
393     } else {
394         ret = USB_RET_ASYNC;
395         usb_packet_set_state(p, USB_PACKET_QUEUED);
396         QTAILQ_INSERT_TAIL(&p->ep->queue, p, queue);
397     }
398     return ret;
399 }
400 
401 /* Notify the controller that an async packet is complete.  This should only
402    be called for packets previously deferred by returning USB_RET_ASYNC from
403    handle_packet. */
404 void usb_packet_complete(USBDevice *dev, USBPacket *p)
405 {
406     USBEndpoint *ep = p->ep;
407     int ret;
408 
409     usb_packet_check_state(p, USB_PACKET_ASYNC);
410     assert(QTAILQ_FIRST(&ep->queue) == p);
411     usb_packet_set_state(p, USB_PACKET_COMPLETE);
412     QTAILQ_REMOVE(&ep->queue, p, queue);
413     dev->port->ops->complete(dev->port, p);
414 
415     while (!QTAILQ_EMPTY(&ep->queue)) {
416         p = QTAILQ_FIRST(&ep->queue);
417         if (p->state == USB_PACKET_ASYNC) {
418             break;
419         }
420         usb_packet_check_state(p, USB_PACKET_QUEUED);
421         ret = usb_process_one(p);
422         if (ret == USB_RET_ASYNC) {
423             usb_packet_set_state(p, USB_PACKET_ASYNC);
424             break;
425         }
426         p->result = ret;
427         usb_packet_set_state(p, USB_PACKET_COMPLETE);
428         QTAILQ_REMOVE(&ep->queue, p, queue);
429         dev->port->ops->complete(dev->port, p);
430     }
431 }
432 
433 /* Cancel an active packet.  The packed must have been deferred by
434    returning USB_RET_ASYNC from handle_packet, and not yet
435    completed.  */
436 void usb_cancel_packet(USBPacket * p)
437 {
438     bool callback = (p->state == USB_PACKET_ASYNC);
439     assert(usb_packet_is_inflight(p));
440     usb_packet_set_state(p, USB_PACKET_CANCELED);
441     QTAILQ_REMOVE(&p->ep->queue, p, queue);
442     if (callback) {
443         usb_device_cancel_packet(p->ep->dev, p);
444     }
445 }
446 
447 
448 void usb_packet_init(USBPacket *p)
449 {
450     qemu_iovec_init(&p->iov, 1);
451 }
452 
453 static const char *usb_packet_state_name(USBPacketState state)
454 {
455     static const char *name[] = {
456         [USB_PACKET_UNDEFINED] = "undef",
457         [USB_PACKET_SETUP]     = "setup",
458         [USB_PACKET_QUEUED]    = "queued",
459         [USB_PACKET_ASYNC]     = "async",
460         [USB_PACKET_COMPLETE]  = "complete",
461         [USB_PACKET_CANCELED]  = "canceled",
462     };
463     if (state < ARRAY_SIZE(name)) {
464         return name[state];
465     }
466     return "INVALID";
467 }
468 
469 void usb_packet_check_state(USBPacket *p, USBPacketState expected)
470 {
471     USBDevice *dev;
472     USBBus *bus;
473 
474     if (p->state == expected) {
475         return;
476     }
477     dev = p->ep->dev;
478     bus = usb_bus_from_device(dev);
479     trace_usb_packet_state_fault(bus->busnr, dev->port->path, p->ep->nr, p,
480                                  usb_packet_state_name(p->state),
481                                  usb_packet_state_name(expected));
482     assert(!"usb packet state check failed");
483 }
484 
485 void usb_packet_set_state(USBPacket *p, USBPacketState state)
486 {
487     if (p->ep) {
488         USBDevice *dev = p->ep->dev;
489         USBBus *bus = usb_bus_from_device(dev);
490         trace_usb_packet_state_change(bus->busnr, dev->port->path, p->ep->nr, p,
491                                       usb_packet_state_name(p->state),
492                                       usb_packet_state_name(state));
493     } else {
494         trace_usb_packet_state_change(-1, "", -1, p,
495                                       usb_packet_state_name(p->state),
496                                       usb_packet_state_name(state));
497     }
498     p->state = state;
499 }
500 
501 void usb_packet_setup(USBPacket *p, int pid, USBEndpoint *ep)
502 {
503     assert(!usb_packet_is_inflight(p));
504     p->pid = pid;
505     p->ep = ep;
506     p->result = 0;
507     p->parameter = 0;
508     qemu_iovec_reset(&p->iov);
509     usb_packet_set_state(p, USB_PACKET_SETUP);
510 }
511 
512 void usb_packet_addbuf(USBPacket *p, void *ptr, size_t len)
513 {
514     qemu_iovec_add(&p->iov, ptr, len);
515 }
516 
517 void usb_packet_copy(USBPacket *p, void *ptr, size_t bytes)
518 {
519     assert(p->result >= 0);
520     assert(p->result + bytes <= p->iov.size);
521     switch (p->pid) {
522     case USB_TOKEN_SETUP:
523     case USB_TOKEN_OUT:
524         iov_to_buf(p->iov.iov, p->iov.niov, ptr, p->result, bytes);
525         break;
526     case USB_TOKEN_IN:
527         iov_from_buf(p->iov.iov, p->iov.niov, ptr, p->result, bytes);
528         break;
529     default:
530         fprintf(stderr, "%s: invalid pid: %x\n", __func__, p->pid);
531         abort();
532     }
533     p->result += bytes;
534 }
535 
536 void usb_packet_skip(USBPacket *p, size_t bytes)
537 {
538     assert(p->result >= 0);
539     assert(p->result + bytes <= p->iov.size);
540     if (p->pid == USB_TOKEN_IN) {
541         iov_clear(p->iov.iov, p->iov.niov, p->result, bytes);
542     }
543     p->result += bytes;
544 }
545 
546 void usb_packet_cleanup(USBPacket *p)
547 {
548     assert(!usb_packet_is_inflight(p));
549     qemu_iovec_destroy(&p->iov);
550 }
551 
552 void usb_ep_init(USBDevice *dev)
553 {
554     int ep;
555 
556     dev->ep_ctl.nr = 0;
557     dev->ep_ctl.type = USB_ENDPOINT_XFER_CONTROL;
558     dev->ep_ctl.ifnum = 0;
559     dev->ep_ctl.dev = dev;
560     dev->ep_ctl.pipeline = false;
561     QTAILQ_INIT(&dev->ep_ctl.queue);
562     for (ep = 0; ep < USB_MAX_ENDPOINTS; ep++) {
563         dev->ep_in[ep].nr = ep + 1;
564         dev->ep_out[ep].nr = ep + 1;
565         dev->ep_in[ep].pid = USB_TOKEN_IN;
566         dev->ep_out[ep].pid = USB_TOKEN_OUT;
567         dev->ep_in[ep].type = USB_ENDPOINT_XFER_INVALID;
568         dev->ep_out[ep].type = USB_ENDPOINT_XFER_INVALID;
569         dev->ep_in[ep].ifnum = 0;
570         dev->ep_out[ep].ifnum = 0;
571         dev->ep_in[ep].dev = dev;
572         dev->ep_out[ep].dev = dev;
573         dev->ep_in[ep].pipeline = false;
574         dev->ep_out[ep].pipeline = false;
575         QTAILQ_INIT(&dev->ep_in[ep].queue);
576         QTAILQ_INIT(&dev->ep_out[ep].queue);
577     }
578 }
579 
580 void usb_ep_dump(USBDevice *dev)
581 {
582     static const char *tname[] = {
583         [USB_ENDPOINT_XFER_CONTROL] = "control",
584         [USB_ENDPOINT_XFER_ISOC]    = "isoc",
585         [USB_ENDPOINT_XFER_BULK]    = "bulk",
586         [USB_ENDPOINT_XFER_INT]     = "int",
587     };
588     int ifnum, ep, first;
589 
590     fprintf(stderr, "Device \"%s\", config %d\n",
591             dev->product_desc, dev->configuration);
592     for (ifnum = 0; ifnum < 16; ifnum++) {
593         first = 1;
594         for (ep = 0; ep < USB_MAX_ENDPOINTS; ep++) {
595             if (dev->ep_in[ep].type != USB_ENDPOINT_XFER_INVALID &&
596                 dev->ep_in[ep].ifnum == ifnum) {
597                 if (first) {
598                     first = 0;
599                     fprintf(stderr, "  Interface %d, alternative %d\n",
600                             ifnum, dev->altsetting[ifnum]);
601                 }
602                 fprintf(stderr, "    Endpoint %d, IN, %s, %d max\n", ep,
603                         tname[dev->ep_in[ep].type],
604                         dev->ep_in[ep].max_packet_size);
605             }
606             if (dev->ep_out[ep].type != USB_ENDPOINT_XFER_INVALID &&
607                 dev->ep_out[ep].ifnum == ifnum) {
608                 if (first) {
609                     first = 0;
610                     fprintf(stderr, "  Interface %d, alternative %d\n",
611                             ifnum, dev->altsetting[ifnum]);
612                 }
613                 fprintf(stderr, "    Endpoint %d, OUT, %s, %d max\n", ep,
614                         tname[dev->ep_out[ep].type],
615                         dev->ep_out[ep].max_packet_size);
616             }
617         }
618     }
619     fprintf(stderr, "--\n");
620 }
621 
622 struct USBEndpoint *usb_ep_get(USBDevice *dev, int pid, int ep)
623 {
624     struct USBEndpoint *eps;
625 
626     if (dev == NULL) {
627         return NULL;
628     }
629     eps = (pid == USB_TOKEN_IN) ? dev->ep_in : dev->ep_out;
630     if (ep == 0) {
631         return &dev->ep_ctl;
632     }
633     assert(pid == USB_TOKEN_IN || pid == USB_TOKEN_OUT);
634     assert(ep > 0 && ep <= USB_MAX_ENDPOINTS);
635     return eps + ep - 1;
636 }
637 
638 uint8_t usb_ep_get_type(USBDevice *dev, int pid, int ep)
639 {
640     struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);
641     return uep->type;
642 }
643 
644 void usb_ep_set_type(USBDevice *dev, int pid, int ep, uint8_t type)
645 {
646     struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);
647     uep->type = type;
648 }
649 
650 uint8_t usb_ep_get_ifnum(USBDevice *dev, int pid, int ep)
651 {
652     struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);
653     return uep->ifnum;
654 }
655 
656 void usb_ep_set_ifnum(USBDevice *dev, int pid, int ep, uint8_t ifnum)
657 {
658     struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);
659     uep->ifnum = ifnum;
660 }
661 
662 void usb_ep_set_max_packet_size(USBDevice *dev, int pid, int ep,
663                                 uint16_t raw)
664 {
665     struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);
666     int size, microframes;
667 
668     size = raw & 0x7ff;
669     switch ((raw >> 11) & 3) {
670     case 1:
671         microframes = 2;
672         break;
673     case 2:
674         microframes = 3;
675         break;
676     default:
677         microframes = 1;
678         break;
679     }
680     uep->max_packet_size = size * microframes;
681 }
682 
683 int usb_ep_get_max_packet_size(USBDevice *dev, int pid, int ep)
684 {
685     struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);
686     return uep->max_packet_size;
687 }
688 
689 void usb_ep_set_pipeline(USBDevice *dev, int pid, int ep, bool enabled)
690 {
691     struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);
692     uep->pipeline = enabled;
693 }
694