xref: /openbmc/qemu/hw/usb/bus.c (revision 831734cc)
1 #include "qemu/osdep.h"
2 #include "hw/qdev-properties.h"
3 #include "hw/usb.h"
4 #include "qapi/error.h"
5 #include "qemu/error-report.h"
6 #include "qemu/module.h"
7 #include "sysemu/sysemu.h"
8 #include "migration/vmstate.h"
9 #include "monitor/monitor.h"
10 #include "trace.h"
11 #include "qemu/cutils.h"
12 
13 static void usb_bus_dev_print(Monitor *mon, DeviceState *qdev, int indent);
14 
15 static char *usb_get_dev_path(DeviceState *dev);
16 static char *usb_get_fw_dev_path(DeviceState *qdev);
17 static void usb_qdev_unrealize(DeviceState *qdev);
18 
19 static Property usb_props[] = {
20     DEFINE_PROP_STRING("port", USBDevice, port_path),
21     DEFINE_PROP_STRING("serial", USBDevice, serial),
22     DEFINE_PROP_BIT("full-path", USBDevice, flags,
23                     USB_DEV_FLAG_FULL_PATH, true),
24     DEFINE_PROP_BIT("msos-desc", USBDevice, flags,
25                     USB_DEV_FLAG_MSOS_DESC_ENABLE, true),
26     DEFINE_PROP_STRING("pcap", USBDevice, pcap_filename),
27     DEFINE_PROP_END_OF_LIST()
28 };
29 
30 static void usb_bus_class_init(ObjectClass *klass, void *data)
31 {
32     BusClass *k = BUS_CLASS(klass);
33     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
34 
35     k->print_dev = usb_bus_dev_print;
36     k->get_dev_path = usb_get_dev_path;
37     k->get_fw_dev_path = usb_get_fw_dev_path;
38     hc->unplug = qdev_simple_device_unplug_cb;
39 }
40 
41 static const TypeInfo usb_bus_info = {
42     .name = TYPE_USB_BUS,
43     .parent = TYPE_BUS,
44     .instance_size = sizeof(USBBus),
45     .class_init = usb_bus_class_init,
46     .interfaces = (InterfaceInfo[]) {
47         { TYPE_HOTPLUG_HANDLER },
48         { }
49     }
50 };
51 
52 static int next_usb_bus = 0;
53 static QTAILQ_HEAD(, USBBus) busses = QTAILQ_HEAD_INITIALIZER(busses);
54 
55 static int usb_device_post_load(void *opaque, int version_id)
56 {
57     USBDevice *dev = opaque;
58 
59     if (dev->state == USB_STATE_NOTATTACHED) {
60         dev->attached = false;
61     } else {
62         dev->attached = true;
63     }
64     return 0;
65 }
66 
67 const VMStateDescription vmstate_usb_device = {
68     .name = "USBDevice",
69     .version_id = 1,
70     .minimum_version_id = 1,
71     .post_load = usb_device_post_load,
72     .fields = (VMStateField[]) {
73         VMSTATE_UINT8(addr, USBDevice),
74         VMSTATE_INT32(state, USBDevice),
75         VMSTATE_INT32(remote_wakeup, USBDevice),
76         VMSTATE_INT32(setup_state, USBDevice),
77         VMSTATE_INT32(setup_len, USBDevice),
78         VMSTATE_INT32(setup_index, USBDevice),
79         VMSTATE_UINT8_ARRAY(setup_buf, USBDevice, 8),
80         VMSTATE_END_OF_LIST(),
81     }
82 };
83 
84 void usb_bus_new(USBBus *bus, size_t bus_size,
85                  USBBusOps *ops, DeviceState *host)
86 {
87     qbus_create_inplace(bus, bus_size, TYPE_USB_BUS, host, NULL);
88     qbus_set_bus_hotplug_handler(BUS(bus));
89     bus->ops = ops;
90     bus->busnr = next_usb_bus++;
91     QTAILQ_INIT(&bus->free);
92     QTAILQ_INIT(&bus->used);
93     QTAILQ_INSERT_TAIL(&busses, bus, next);
94 }
95 
96 void usb_bus_release(USBBus *bus)
97 {
98     assert(next_usb_bus > 0);
99 
100     QTAILQ_REMOVE(&busses, bus, next);
101 }
102 
103 USBBus *usb_bus_find(int busnr)
104 {
105     USBBus *bus;
106 
107     if (-1 == busnr)
108         return QTAILQ_FIRST(&busses);
109     QTAILQ_FOREACH(bus, &busses, next) {
110         if (bus->busnr == busnr)
111             return bus;
112     }
113     return NULL;
114 }
115 
116 static void usb_device_realize(USBDevice *dev, Error **errp)
117 {
118     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
119 
120     if (klass->realize) {
121         klass->realize(dev, errp);
122     }
123 }
124 
125 USBDevice *usb_device_find_device(USBDevice *dev, uint8_t addr)
126 {
127     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
128     if (klass->find_device) {
129         return klass->find_device(dev, addr);
130     }
131     return NULL;
132 }
133 
134 static void usb_device_unrealize(USBDevice *dev)
135 {
136     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
137 
138     if (klass->unrealize) {
139         klass->unrealize(dev);
140     }
141 }
142 
143 void usb_device_cancel_packet(USBDevice *dev, USBPacket *p)
144 {
145     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
146     if (klass->cancel_packet) {
147         klass->cancel_packet(dev, p);
148     }
149 }
150 
151 void usb_device_handle_attach(USBDevice *dev)
152 {
153     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
154     if (klass->handle_attach) {
155         klass->handle_attach(dev);
156     }
157 }
158 
159 void usb_device_handle_reset(USBDevice *dev)
160 {
161     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
162     if (klass->handle_reset) {
163         klass->handle_reset(dev);
164     }
165 }
166 
167 void usb_device_handle_control(USBDevice *dev, USBPacket *p, int request,
168                                int value, int index, int length, uint8_t *data)
169 {
170     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
171     if (klass->handle_control) {
172         klass->handle_control(dev, p, request, value, index, length, data);
173     }
174 }
175 
176 void usb_device_handle_data(USBDevice *dev, USBPacket *p)
177 {
178     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
179     if (klass->handle_data) {
180         klass->handle_data(dev, p);
181     }
182 }
183 
184 const char *usb_device_get_product_desc(USBDevice *dev)
185 {
186     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
187     return klass->product_desc;
188 }
189 
190 const USBDesc *usb_device_get_usb_desc(USBDevice *dev)
191 {
192     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
193     if (dev->usb_desc) {
194         return dev->usb_desc;
195     }
196     return klass->usb_desc;
197 }
198 
199 void usb_device_set_interface(USBDevice *dev, int interface,
200                               int alt_old, int alt_new)
201 {
202     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
203     if (klass->set_interface) {
204         klass->set_interface(dev, interface, alt_old, alt_new);
205     }
206 }
207 
208 void usb_device_flush_ep_queue(USBDevice *dev, USBEndpoint *ep)
209 {
210     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
211     if (klass->flush_ep_queue) {
212         klass->flush_ep_queue(dev, ep);
213     }
214 }
215 
216 void usb_device_ep_stopped(USBDevice *dev, USBEndpoint *ep)
217 {
218     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
219     if (klass->ep_stopped) {
220         klass->ep_stopped(dev, ep);
221     }
222 }
223 
224 int usb_device_alloc_streams(USBDevice *dev, USBEndpoint **eps, int nr_eps,
225                              int streams)
226 {
227     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
228     if (klass->alloc_streams) {
229         return klass->alloc_streams(dev, eps, nr_eps, streams);
230     }
231     return 0;
232 }
233 
234 void usb_device_free_streams(USBDevice *dev, USBEndpoint **eps, int nr_eps)
235 {
236     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
237     if (klass->free_streams) {
238         klass->free_streams(dev, eps, nr_eps);
239     }
240 }
241 
242 static void usb_qdev_realize(DeviceState *qdev, Error **errp)
243 {
244     USBDevice *dev = USB_DEVICE(qdev);
245     Error *local_err = NULL;
246 
247     pstrcpy(dev->product_desc, sizeof(dev->product_desc),
248             usb_device_get_product_desc(dev));
249     dev->auto_attach = 1;
250     QLIST_INIT(&dev->strings);
251     usb_ep_init(dev);
252 
253     usb_claim_port(dev, &local_err);
254     if (local_err) {
255         error_propagate(errp, local_err);
256         return;
257     }
258 
259     usb_device_realize(dev, &local_err);
260     if (local_err) {
261         usb_release_port(dev);
262         error_propagate(errp, local_err);
263         return;
264     }
265 
266     if (dev->auto_attach) {
267         usb_device_attach(dev, &local_err);
268         if (local_err) {
269             usb_qdev_unrealize(qdev);
270             error_propagate(errp, local_err);
271             return;
272         }
273     }
274 
275     if (dev->pcap_filename) {
276         int fd = qemu_open_old(dev->pcap_filename, O_CREAT | O_WRONLY | O_TRUNC, 0666);
277         if (fd < 0) {
278             error_setg(errp, "open %s failed", dev->pcap_filename);
279             usb_qdev_unrealize(qdev);
280             return;
281         }
282         dev->pcap = fdopen(fd, "w");
283         usb_pcap_init(dev->pcap);
284     }
285 }
286 
287 static void usb_qdev_unrealize(DeviceState *qdev)
288 {
289     USBDevice *dev = USB_DEVICE(qdev);
290     USBDescString *s, *next;
291 
292     QLIST_FOREACH_SAFE(s, &dev->strings, next, next) {
293         QLIST_REMOVE(s, next);
294         g_free(s->str);
295         g_free(s);
296     }
297 
298     if (dev->pcap) {
299         fclose(dev->pcap);
300     }
301 
302     if (dev->attached) {
303         usb_device_detach(dev);
304     }
305     usb_device_unrealize(dev);
306     if (dev->port) {
307         usb_release_port(dev);
308     }
309 }
310 
311 typedef struct LegacyUSBFactory
312 {
313     const char *name;
314     const char *usbdevice_name;
315     USBDevice *(*usbdevice_init)(const char *params);
316 } LegacyUSBFactory;
317 
318 static GSList *legacy_usb_factory;
319 
320 void usb_legacy_register(const char *typename, const char *usbdevice_name,
321                          USBDevice *(*usbdevice_init)(const char *params))
322 {
323     if (usbdevice_name) {
324         LegacyUSBFactory *f = g_malloc0(sizeof(*f));
325         f->name = typename;
326         f->usbdevice_name = usbdevice_name;
327         f->usbdevice_init = usbdevice_init;
328         legacy_usb_factory = g_slist_append(legacy_usb_factory, f);
329     }
330 }
331 
332 USBDevice *usb_new(const char *name)
333 {
334     return USB_DEVICE(qdev_new(name));
335 }
336 
337 static USBDevice *usb_try_new(const char *name)
338 {
339     return USB_DEVICE(qdev_try_new(name));
340 }
341 
342 bool usb_realize_and_unref(USBDevice *dev, USBBus *bus, Error **errp)
343 {
344     return qdev_realize_and_unref(&dev->qdev, &bus->qbus, errp);
345 }
346 
347 USBDevice *usb_create_simple(USBBus *bus, const char *name)
348 {
349     USBDevice *dev = usb_new(name);
350 
351     usb_realize_and_unref(dev, bus, &error_abort);
352     return dev;
353 }
354 
355 static void usb_fill_port(USBPort *port, void *opaque, int index,
356                           USBPortOps *ops, int speedmask)
357 {
358     port->opaque = opaque;
359     port->index = index;
360     port->ops = ops;
361     port->speedmask = speedmask;
362     usb_port_location(port, NULL, index + 1);
363 }
364 
365 void usb_register_port(USBBus *bus, USBPort *port, void *opaque, int index,
366                        USBPortOps *ops, int speedmask)
367 {
368     usb_fill_port(port, opaque, index, ops, speedmask);
369     QTAILQ_INSERT_TAIL(&bus->free, port, next);
370     bus->nfree++;
371 }
372 
373 void usb_register_companion(const char *masterbus, USBPort *ports[],
374                             uint32_t portcount, uint32_t firstport,
375                             void *opaque, USBPortOps *ops, int speedmask,
376                             Error **errp)
377 {
378     USBBus *bus;
379     int i;
380 
381     QTAILQ_FOREACH(bus, &busses, next) {
382         if (strcmp(bus->qbus.name, masterbus) == 0) {
383             break;
384         }
385     }
386 
387     if (!bus) {
388         error_setg(errp, "USB bus '%s' not found", masterbus);
389         return;
390     }
391     if (!bus->ops->register_companion) {
392         error_setg(errp, "Can't use USB bus '%s' as masterbus,"
393                    " it doesn't support companion controllers",
394                    masterbus);
395         return;
396     }
397 
398     for (i = 0; i < portcount; i++) {
399         usb_fill_port(ports[i], opaque, i, ops, speedmask);
400     }
401 
402     bus->ops->register_companion(bus, ports, portcount, firstport, errp);
403 }
404 
405 void usb_port_location(USBPort *downstream, USBPort *upstream, int portnr)
406 {
407     if (upstream) {
408         int l = snprintf(downstream->path, sizeof(downstream->path), "%s.%d",
409                          upstream->path, portnr);
410         /* Max string is nn.nn.nn.nn.nn, which fits in 16 bytes */
411         assert(l < sizeof(downstream->path));
412         downstream->hubcount = upstream->hubcount + 1;
413     } else {
414         snprintf(downstream->path, sizeof(downstream->path), "%d", portnr);
415         downstream->hubcount = 0;
416     }
417 }
418 
419 void usb_unregister_port(USBBus *bus, USBPort *port)
420 {
421     if (port->dev) {
422         object_unparent(OBJECT(port->dev));
423     }
424     QTAILQ_REMOVE(&bus->free, port, next);
425     bus->nfree--;
426 }
427 
428 void usb_claim_port(USBDevice *dev, Error **errp)
429 {
430     USBBus *bus = usb_bus_from_device(dev);
431     USBPort *port;
432     USBDevice *hub;
433 
434     assert(dev->port == NULL);
435 
436     if (dev->port_path) {
437         QTAILQ_FOREACH(port, &bus->free, next) {
438             if (strcmp(port->path, dev->port_path) == 0) {
439                 break;
440             }
441         }
442         if (port == NULL) {
443             error_setg(errp, "usb port %s (bus %s) not found (in use?)",
444                        dev->port_path, bus->qbus.name);
445             return;
446         }
447     } else {
448         if (bus->nfree == 1 && strcmp(object_get_typename(OBJECT(dev)), "usb-hub") != 0) {
449             /* Create a new hub and chain it on */
450             hub = usb_try_new("usb-hub");
451             if (hub) {
452                 usb_realize_and_unref(hub, bus, NULL);
453             }
454         }
455         if (bus->nfree == 0) {
456             error_setg(errp, "tried to attach usb device %s to a bus "
457                        "with no free ports", dev->product_desc);
458             return;
459         }
460         port = QTAILQ_FIRST(&bus->free);
461     }
462     trace_usb_port_claim(bus->busnr, port->path);
463 
464     QTAILQ_REMOVE(&bus->free, port, next);
465     bus->nfree--;
466 
467     dev->port = port;
468     port->dev = dev;
469 
470     QTAILQ_INSERT_TAIL(&bus->used, port, next);
471     bus->nused++;
472 }
473 
474 void usb_release_port(USBDevice *dev)
475 {
476     USBBus *bus = usb_bus_from_device(dev);
477     USBPort *port = dev->port;
478 
479     assert(port != NULL);
480     trace_usb_port_release(bus->busnr, port->path);
481 
482     QTAILQ_REMOVE(&bus->used, port, next);
483     bus->nused--;
484 
485     dev->port = NULL;
486     port->dev = NULL;
487 
488     QTAILQ_INSERT_TAIL(&bus->free, port, next);
489     bus->nfree++;
490 }
491 
492 static void usb_mask_to_str(char *dest, size_t size,
493                             unsigned int speedmask)
494 {
495     static const struct {
496         unsigned int mask;
497         const char *name;
498     } speeds[] = {
499         { .mask = USB_SPEED_MASK_FULL,  .name = "full"  },
500         { .mask = USB_SPEED_MASK_HIGH,  .name = "high"  },
501         { .mask = USB_SPEED_MASK_SUPER, .name = "super" },
502     };
503     int i, pos = 0;
504 
505     for (i = 0; i < ARRAY_SIZE(speeds); i++) {
506         if (speeds[i].mask & speedmask) {
507             pos += snprintf(dest + pos, size - pos, "%s%s",
508                             pos ? "+" : "",
509                             speeds[i].name);
510         }
511     }
512 
513     if (pos == 0) {
514         snprintf(dest, size, "unknown");
515     }
516 }
517 
518 void usb_check_attach(USBDevice *dev, Error **errp)
519 {
520     USBBus *bus = usb_bus_from_device(dev);
521     USBPort *port = dev->port;
522     char devspeed[32], portspeed[32];
523 
524     assert(port != NULL);
525     assert(!dev->attached);
526     usb_mask_to_str(devspeed, sizeof(devspeed), dev->speedmask);
527     usb_mask_to_str(portspeed, sizeof(portspeed), port->speedmask);
528     trace_usb_port_attach(bus->busnr, port->path,
529                           devspeed, portspeed);
530 
531     if (!(port->speedmask & dev->speedmask)) {
532         error_setg(errp, "Warning: speed mismatch trying to attach"
533                    " usb device \"%s\" (%s speed)"
534                    " to bus \"%s\", port \"%s\" (%s speed)",
535                    dev->product_desc, devspeed,
536                    bus->qbus.name, port->path, portspeed);
537         return;
538     }
539 }
540 
541 void usb_device_attach(USBDevice *dev, Error **errp)
542 {
543     USBPort *port = dev->port;
544     Error *local_err = NULL;
545 
546     usb_check_attach(dev, &local_err);
547     if (local_err) {
548         error_propagate(errp, local_err);
549         return;
550     }
551 
552     dev->attached = true;
553     usb_attach(port);
554 }
555 
556 int usb_device_detach(USBDevice *dev)
557 {
558     USBBus *bus = usb_bus_from_device(dev);
559     USBPort *port = dev->port;
560 
561     assert(port != NULL);
562     assert(dev->attached);
563     trace_usb_port_detach(bus->busnr, port->path);
564 
565     usb_detach(port);
566     dev->attached = false;
567     return 0;
568 }
569 
570 static const char *usb_speed(unsigned int speed)
571 {
572     static const char *txt[] = {
573         [ USB_SPEED_LOW  ] = "1.5",
574         [ USB_SPEED_FULL ] = "12",
575         [ USB_SPEED_HIGH ] = "480",
576         [ USB_SPEED_SUPER ] = "5000",
577     };
578     if (speed >= ARRAY_SIZE(txt))
579         return "?";
580     return txt[speed];
581 }
582 
583 static void usb_bus_dev_print(Monitor *mon, DeviceState *qdev, int indent)
584 {
585     USBDevice *dev = USB_DEVICE(qdev);
586     USBBus *bus = usb_bus_from_device(dev);
587 
588     monitor_printf(mon, "%*saddr %d.%d, port %s, speed %s, name %s%s\n",
589                    indent, "", bus->busnr, dev->addr,
590                    dev->port ? dev->port->path : "-",
591                    usb_speed(dev->speed), dev->product_desc,
592                    dev->attached ? ", attached" : "");
593 }
594 
595 static char *usb_get_dev_path(DeviceState *qdev)
596 {
597     USBDevice *dev = USB_DEVICE(qdev);
598     DeviceState *hcd = qdev->parent_bus->parent;
599     char *id = NULL;
600 
601     if (dev->flags & (1 << USB_DEV_FLAG_FULL_PATH)) {
602         id = qdev_get_dev_path(hcd);
603     }
604     if (id) {
605         char *ret = g_strdup_printf("%s/%s", id, dev->port->path);
606         g_free(id);
607         return ret;
608     } else {
609         return g_strdup(dev->port->path);
610     }
611 }
612 
613 static char *usb_get_fw_dev_path(DeviceState *qdev)
614 {
615     USBDevice *dev = USB_DEVICE(qdev);
616     char *fw_path, *in;
617     ssize_t pos = 0, fw_len;
618     long nr;
619 
620     fw_len = 32 + strlen(dev->port->path) * 6;
621     fw_path = g_malloc(fw_len);
622     in = dev->port->path;
623     while (fw_len - pos > 0) {
624         nr = strtol(in, &in, 10);
625         if (in[0] == '.') {
626             /* some hub between root port and device */
627             pos += snprintf(fw_path + pos, fw_len - pos, "hub@%lx/", nr);
628             in++;
629         } else {
630             /* the device itself */
631             snprintf(fw_path + pos, fw_len - pos, "%s@%lx",
632                      qdev_fw_name(qdev), nr);
633             break;
634         }
635     }
636     return fw_path;
637 }
638 
639 void hmp_info_usb(Monitor *mon, const QDict *qdict)
640 {
641     USBBus *bus;
642     USBDevice *dev;
643     USBPort *port;
644 
645     if (QTAILQ_EMPTY(&busses)) {
646         monitor_printf(mon, "USB support not enabled\n");
647         return;
648     }
649 
650     QTAILQ_FOREACH(bus, &busses, next) {
651         QTAILQ_FOREACH(port, &bus->used, next) {
652             dev = port->dev;
653             if (!dev)
654                 continue;
655             monitor_printf(mon, "  Device %d.%d, Port %s, Speed %s Mb/s, "
656                            "Product %s%s%s\n",
657                            bus->busnr, dev->addr, port->path,
658                            usb_speed(dev->speed), dev->product_desc,
659                            dev->qdev.id ? ", ID: " : "",
660                            dev->qdev.id ?: "");
661         }
662     }
663 }
664 
665 /* handle legacy -usbdevice cmd line option */
666 USBDevice *usbdevice_create(const char *cmdline)
667 {
668     USBBus *bus = usb_bus_find(-1 /* any */);
669     LegacyUSBFactory *f = NULL;
670     Error *err = NULL;
671     GSList *i;
672     char driver[32];
673     const char *params;
674     int len;
675     USBDevice *dev;
676 
677     params = strchr(cmdline,':');
678     if (params) {
679         params++;
680         len = params - cmdline;
681         if (len > sizeof(driver))
682             len = sizeof(driver);
683         pstrcpy(driver, len, cmdline);
684     } else {
685         params = "";
686         pstrcpy(driver, sizeof(driver), cmdline);
687     }
688 
689     for (i = legacy_usb_factory; i; i = i->next) {
690         f = i->data;
691         if (strcmp(f->usbdevice_name, driver) == 0) {
692             break;
693         }
694     }
695     if (i == NULL) {
696 #if 0
697         /* no error because some drivers are not converted (yet) */
698         error_report("usbdevice %s not found", driver);
699 #endif
700         return NULL;
701     }
702 
703     if (!bus) {
704         error_report("Error: no usb bus to attach usbdevice %s, "
705                      "please try -machine usb=on and check that "
706                      "the machine model supports USB", driver);
707         return NULL;
708     }
709 
710     if (f->usbdevice_init) {
711         dev = f->usbdevice_init(params);
712     } else {
713         if (*params) {
714             error_report("usbdevice %s accepts no params", driver);
715             return NULL;
716         }
717         dev = usb_new(f->name);
718     }
719     if (!dev) {
720         error_report("Failed to create USB device '%s'", f->name);
721         return NULL;
722     }
723     if (!usb_realize_and_unref(dev, bus, &err)) {
724         error_reportf_err(err, "Failed to initialize USB device '%s': ",
725                           f->name);
726         object_unparent(OBJECT(dev));
727         return NULL;
728     }
729     return dev;
730 }
731 
732 static bool usb_get_attached(Object *obj, Error **errp)
733 {
734     USBDevice *dev = USB_DEVICE(obj);
735 
736     return dev->attached;
737 }
738 
739 static void usb_set_attached(Object *obj, bool value, Error **errp)
740 {
741     USBDevice *dev = USB_DEVICE(obj);
742 
743     if (dev->attached == value) {
744         return;
745     }
746 
747     if (value) {
748         usb_device_attach(dev, errp);
749     } else {
750         usb_device_detach(dev);
751     }
752 }
753 
754 static void usb_device_instance_init(Object *obj)
755 {
756     USBDevice *dev = USB_DEVICE(obj);
757     USBDeviceClass *klass = USB_DEVICE_GET_CLASS(dev);
758 
759     if (klass->attached_settable) {
760         object_property_add_bool(obj, "attached",
761                                  usb_get_attached, usb_set_attached);
762     } else {
763         object_property_add_bool(obj, "attached",
764                                  usb_get_attached, NULL);
765     }
766 }
767 
768 static void usb_device_class_init(ObjectClass *klass, void *data)
769 {
770     DeviceClass *k = DEVICE_CLASS(klass);
771     k->bus_type = TYPE_USB_BUS;
772     k->realize  = usb_qdev_realize;
773     k->unrealize = usb_qdev_unrealize;
774     device_class_set_props(k, usb_props);
775 }
776 
777 static const TypeInfo usb_device_type_info = {
778     .name = TYPE_USB_DEVICE,
779     .parent = TYPE_DEVICE,
780     .instance_size = sizeof(USBDevice),
781     .instance_init = usb_device_instance_init,
782     .abstract = true,
783     .class_size = sizeof(USBDeviceClass),
784     .class_init = usb_device_class_init,
785 };
786 
787 static void usb_register_types(void)
788 {
789     type_register_static(&usb_bus_info);
790     type_register_static(&usb_device_type_info);
791 }
792 
793 type_init(usb_register_types)
794