xref: /qemu/hw/usb/desc.c (revision ce32a9e9)
1 #include "qemu/osdep.h"
2 
3 #include "hw/usb.h"
4 #include "desc.h"
5 #include "trace.h"
6 
7 /* ------------------------------------------------------------------ */
8 
9 int usb_desc_device(const USBDescID *id, const USBDescDevice *dev,
10                     bool msos, uint8_t *dest, size_t len)
11 {
12     uint8_t bLength = 0x12;
13     USBDescriptor *d = (void *)dest;
14 
15     if (len < bLength) {
16         return -1;
17     }
18 
19     d->bLength                     = bLength;
20     d->bDescriptorType             = USB_DT_DEVICE;
21 
22     if (msos && dev->bcdUSB < 0x0200) {
23         /*
24          * Version 2.0+ required for microsoft os descriptors to work.
25          * Done this way so msos-desc compat property will handle both
26          * the version and the new descriptors being present.
27          */
28         d->u.device.bcdUSB_lo          = usb_lo(0x0200);
29         d->u.device.bcdUSB_hi          = usb_hi(0x0200);
30     } else {
31         d->u.device.bcdUSB_lo          = usb_lo(dev->bcdUSB);
32         d->u.device.bcdUSB_hi          = usb_hi(dev->bcdUSB);
33     }
34     d->u.device.bDeviceClass       = dev->bDeviceClass;
35     d->u.device.bDeviceSubClass    = dev->bDeviceSubClass;
36     d->u.device.bDeviceProtocol    = dev->bDeviceProtocol;
37     d->u.device.bMaxPacketSize0    = dev->bMaxPacketSize0;
38 
39     d->u.device.idVendor_lo        = usb_lo(id->idVendor);
40     d->u.device.idVendor_hi        = usb_hi(id->idVendor);
41     d->u.device.idProduct_lo       = usb_lo(id->idProduct);
42     d->u.device.idProduct_hi       = usb_hi(id->idProduct);
43     d->u.device.bcdDevice_lo       = usb_lo(id->bcdDevice);
44     d->u.device.bcdDevice_hi       = usb_hi(id->bcdDevice);
45     d->u.device.iManufacturer      = id->iManufacturer;
46     d->u.device.iProduct           = id->iProduct;
47     d->u.device.iSerialNumber      = id->iSerialNumber;
48 
49     d->u.device.bNumConfigurations = dev->bNumConfigurations;
50 
51     return bLength;
52 }
53 
54 int usb_desc_device_qualifier(const USBDescDevice *dev,
55                               uint8_t *dest, size_t len)
56 {
57     uint8_t bLength = 0x0a;
58     USBDescriptor *d = (void *)dest;
59 
60     if (len < bLength) {
61         return -1;
62     }
63 
64     d->bLength                               = bLength;
65     d->bDescriptorType                       = USB_DT_DEVICE_QUALIFIER;
66 
67     d->u.device_qualifier.bcdUSB_lo          = usb_lo(dev->bcdUSB);
68     d->u.device_qualifier.bcdUSB_hi          = usb_hi(dev->bcdUSB);
69     d->u.device_qualifier.bDeviceClass       = dev->bDeviceClass;
70     d->u.device_qualifier.bDeviceSubClass    = dev->bDeviceSubClass;
71     d->u.device_qualifier.bDeviceProtocol    = dev->bDeviceProtocol;
72     d->u.device_qualifier.bMaxPacketSize0    = dev->bMaxPacketSize0;
73     d->u.device_qualifier.bNumConfigurations = dev->bNumConfigurations;
74     d->u.device_qualifier.bReserved          = 0;
75 
76     return bLength;
77 }
78 
79 int usb_desc_config(const USBDescConfig *conf, int flags,
80                     uint8_t *dest, size_t len)
81 {
82     uint8_t  bLength = 0x09;
83     uint16_t wTotalLength = 0;
84     USBDescriptor *d = (void *)dest;
85     int i, rc;
86 
87     if (len < bLength) {
88         return -1;
89     }
90 
91     d->bLength                      = bLength;
92     d->bDescriptorType              = USB_DT_CONFIG;
93 
94     d->u.config.bNumInterfaces      = conf->bNumInterfaces;
95     d->u.config.bConfigurationValue = conf->bConfigurationValue;
96     d->u.config.iConfiguration      = conf->iConfiguration;
97     d->u.config.bmAttributes        = conf->bmAttributes;
98     d->u.config.bMaxPower           = conf->bMaxPower;
99     wTotalLength += bLength;
100 
101     /* handle grouped interfaces if any */
102     for (i = 0; i < conf->nif_groups; i++) {
103         rc = usb_desc_iface_group(&(conf->if_groups[i]), flags,
104                                   dest + wTotalLength,
105                                   len - wTotalLength);
106         if (rc < 0) {
107             return rc;
108         }
109         wTotalLength += rc;
110     }
111 
112     /* handle normal (ungrouped / no IAD) interfaces if any */
113     for (i = 0; i < conf->nif; i++) {
114         rc = usb_desc_iface(conf->ifs + i, flags,
115                             dest + wTotalLength, len - wTotalLength);
116         if (rc < 0) {
117             return rc;
118         }
119         wTotalLength += rc;
120     }
121 
122     d->u.config.wTotalLength_lo = usb_lo(wTotalLength);
123     d->u.config.wTotalLength_hi = usb_hi(wTotalLength);
124     return wTotalLength;
125 }
126 
127 int usb_desc_iface_group(const USBDescIfaceAssoc *iad, int flags,
128                          uint8_t *dest, size_t len)
129 {
130     int pos = 0;
131     int i = 0;
132 
133     /* handle interface association descriptor */
134     uint8_t bLength = 0x08;
135 
136     if (len < bLength) {
137         return -1;
138     }
139 
140     dest[0x00] = bLength;
141     dest[0x01] = USB_DT_INTERFACE_ASSOC;
142     dest[0x02] = iad->bFirstInterface;
143     dest[0x03] = iad->bInterfaceCount;
144     dest[0x04] = iad->bFunctionClass;
145     dest[0x05] = iad->bFunctionSubClass;
146     dest[0x06] = iad->bFunctionProtocol;
147     dest[0x07] = iad->iFunction;
148     pos += bLength;
149 
150     /* handle associated interfaces in this group */
151     for (i = 0; i < iad->nif; i++) {
152         int rc = usb_desc_iface(&(iad->ifs[i]), flags, dest + pos, len - pos);
153         if (rc < 0) {
154             return rc;
155         }
156         pos += rc;
157     }
158 
159     return pos;
160 }
161 
162 int usb_desc_iface(const USBDescIface *iface, int flags,
163                    uint8_t *dest, size_t len)
164 {
165     uint8_t bLength = 0x09;
166     int i, rc, pos = 0;
167     USBDescriptor *d = (void *)dest;
168 
169     if (len < bLength) {
170         return -1;
171     }
172 
173     d->bLength                        = bLength;
174     d->bDescriptorType                = USB_DT_INTERFACE;
175 
176     d->u.interface.bInterfaceNumber   = iface->bInterfaceNumber;
177     d->u.interface.bAlternateSetting  = iface->bAlternateSetting;
178     d->u.interface.bNumEndpoints      = iface->bNumEndpoints;
179     d->u.interface.bInterfaceClass    = iface->bInterfaceClass;
180     d->u.interface.bInterfaceSubClass = iface->bInterfaceSubClass;
181     d->u.interface.bInterfaceProtocol = iface->bInterfaceProtocol;
182     d->u.interface.iInterface         = iface->iInterface;
183     pos += bLength;
184 
185     for (i = 0; i < iface->ndesc; i++) {
186         rc = usb_desc_other(iface->descs + i, dest + pos, len - pos);
187         if (rc < 0) {
188             return rc;
189         }
190         pos += rc;
191     }
192 
193     for (i = 0; i < iface->bNumEndpoints; i++) {
194         rc = usb_desc_endpoint(iface->eps + i, flags, dest + pos, len - pos);
195         if (rc < 0) {
196             return rc;
197         }
198         pos += rc;
199     }
200 
201     return pos;
202 }
203 
204 int usb_desc_endpoint(const USBDescEndpoint *ep, int flags,
205                       uint8_t *dest, size_t len)
206 {
207     uint8_t bLength = ep->is_audio ? 0x09 : 0x07;
208     uint8_t extralen = ep->extra ? ep->extra[0] : 0;
209     uint8_t superlen = (flags & USB_DESC_FLAG_SUPER) ? 0x06 : 0;
210     USBDescriptor *d = (void *)dest;
211 
212     if (len < bLength + extralen + superlen) {
213         return -1;
214     }
215 
216     d->bLength                      = bLength;
217     d->bDescriptorType              = USB_DT_ENDPOINT;
218 
219     d->u.endpoint.bEndpointAddress  = ep->bEndpointAddress;
220     d->u.endpoint.bmAttributes      = ep->bmAttributes;
221     d->u.endpoint.wMaxPacketSize_lo = usb_lo(ep->wMaxPacketSize);
222     d->u.endpoint.wMaxPacketSize_hi = usb_hi(ep->wMaxPacketSize);
223     d->u.endpoint.bInterval         = ep->bInterval;
224     if (ep->is_audio) {
225         d->u.endpoint.bRefresh      = ep->bRefresh;
226         d->u.endpoint.bSynchAddress = ep->bSynchAddress;
227     }
228 
229     if (superlen) {
230         d = (void *)(dest + bLength);
231 
232         d->bLength                       = 0x06;
233         d->bDescriptorType               = USB_DT_ENDPOINT_COMPANION;
234 
235         d->u.super_endpoint.bMaxBurst    = ep->bMaxBurst;
236         d->u.super_endpoint.bmAttributes = ep->bmAttributes_super;
237         d->u.super_endpoint.wBytesPerInterval_lo =
238             usb_lo(ep->wBytesPerInterval);
239         d->u.super_endpoint.wBytesPerInterval_hi =
240             usb_hi(ep->wBytesPerInterval);
241     }
242 
243     if (ep->extra) {
244         memcpy(dest + bLength + superlen, ep->extra, extralen);
245     }
246 
247     return bLength + extralen + superlen;
248 }
249 
250 int usb_desc_other(const USBDescOther *desc, uint8_t *dest, size_t len)
251 {
252     int bLength = desc->length ? desc->length : desc->data[0];
253 
254     if (len < bLength) {
255         return -1;
256     }
257 
258     memcpy(dest, desc->data, bLength);
259     return bLength;
260 }
261 
262 static int usb_desc_cap_usb2_ext(const USBDesc *desc, uint8_t *dest, size_t len)
263 {
264     uint8_t  bLength = 0x07;
265     USBDescriptor *d = (void *)dest;
266 
267     if (len < bLength) {
268         return -1;
269     }
270 
271     d->bLength                          = bLength;
272     d->bDescriptorType                  = USB_DT_DEVICE_CAPABILITY;
273     d->u.cap.bDevCapabilityType         = USB_DEV_CAP_USB2_EXT;
274 
275     d->u.cap.u.usb2_ext.bmAttributes_1  = (1 << 1);  /* LPM */
276     d->u.cap.u.usb2_ext.bmAttributes_2  = 0;
277     d->u.cap.u.usb2_ext.bmAttributes_3  = 0;
278     d->u.cap.u.usb2_ext.bmAttributes_4  = 0;
279 
280     return bLength;
281 }
282 
283 static int usb_desc_cap_super(const USBDesc *desc, uint8_t *dest, size_t len)
284 {
285     uint8_t  bLength = 0x0a;
286     USBDescriptor *d = (void *)dest;
287 
288     if (len < bLength) {
289         return -1;
290     }
291 
292     d->bLength                           = bLength;
293     d->bDescriptorType                   = USB_DT_DEVICE_CAPABILITY;
294     d->u.cap.bDevCapabilityType          = USB_DEV_CAP_SUPERSPEED;
295 
296     d->u.cap.u.super.bmAttributes        = 0;
297     d->u.cap.u.super.wSpeedsSupported_lo = 0;
298     d->u.cap.u.super.wSpeedsSupported_hi = 0;
299     d->u.cap.u.super.bFunctionalitySupport = 0;
300     d->u.cap.u.super.bU1DevExitLat       = 0x0a;
301     d->u.cap.u.super.wU2DevExitLat_lo    = 0x20;
302     d->u.cap.u.super.wU2DevExitLat_hi    = 0;
303 
304     if (desc->full) {
305         d->u.cap.u.super.wSpeedsSupported_lo |= (1 << 1);
306         d->u.cap.u.super.bFunctionalitySupport = 1;
307     }
308     if (desc->high) {
309         d->u.cap.u.super.wSpeedsSupported_lo |= (1 << 2);
310         if (!d->u.cap.u.super.bFunctionalitySupport) {
311             d->u.cap.u.super.bFunctionalitySupport = 2;
312         }
313     }
314     if (desc->super) {
315         d->u.cap.u.super.wSpeedsSupported_lo |= (1 << 3);
316         if (!d->u.cap.u.super.bFunctionalitySupport) {
317             d->u.cap.u.super.bFunctionalitySupport = 3;
318         }
319     }
320 
321     return bLength;
322 }
323 
324 static int usb_desc_bos(const USBDesc *desc, uint8_t *dest, size_t len)
325 {
326     uint8_t  bLength = 0x05;
327     uint16_t wTotalLength = 0;
328     uint8_t  bNumDeviceCaps = 0;
329     USBDescriptor *d = (void *)dest;
330     int rc;
331 
332     if (len < bLength) {
333         return -1;
334     }
335 
336     d->bLength                      = bLength;
337     d->bDescriptorType              = USB_DT_BOS;
338 
339     wTotalLength += bLength;
340 
341     if (desc->high != NULL) {
342         rc = usb_desc_cap_usb2_ext(desc, dest + wTotalLength,
343                                    len - wTotalLength);
344         if (rc < 0) {
345             return rc;
346         }
347         wTotalLength += rc;
348         bNumDeviceCaps++;
349     }
350 
351     if (desc->super != NULL) {
352         rc = usb_desc_cap_super(desc, dest + wTotalLength,
353                                 len - wTotalLength);
354         if (rc < 0) {
355             return rc;
356         }
357         wTotalLength += rc;
358         bNumDeviceCaps++;
359     }
360 
361     d->u.bos.wTotalLength_lo = usb_lo(wTotalLength);
362     d->u.bos.wTotalLength_hi = usb_hi(wTotalLength);
363     d->u.bos.bNumDeviceCaps  = bNumDeviceCaps;
364     return wTotalLength;
365 }
366 
367 /* ------------------------------------------------------------------ */
368 
369 static void usb_desc_ep_init(USBDevice *dev)
370 {
371     const USBDescIface *iface;
372     int i, e, pid, ep;
373 
374     usb_ep_init(dev);
375     for (i = 0; i < dev->ninterfaces; i++) {
376         iface = dev->ifaces[i];
377         if (iface == NULL) {
378             continue;
379         }
380         for (e = 0; e < iface->bNumEndpoints; e++) {
381             pid = (iface->eps[e].bEndpointAddress & USB_DIR_IN) ?
382                 USB_TOKEN_IN : USB_TOKEN_OUT;
383             ep = iface->eps[e].bEndpointAddress & 0x0f;
384             usb_ep_set_type(dev, pid, ep, iface->eps[e].bmAttributes & 0x03);
385             usb_ep_set_ifnum(dev, pid, ep, iface->bInterfaceNumber);
386             usb_ep_set_max_packet_size(dev, pid, ep,
387                                        iface->eps[e].wMaxPacketSize);
388             usb_ep_set_max_streams(dev, pid, ep,
389                                    iface->eps[e].bmAttributes_super);
390         }
391     }
392 }
393 
394 static const USBDescIface *usb_desc_find_interface(USBDevice *dev,
395                                                    int nif, int alt)
396 {
397     const USBDescIface *iface;
398     int g, i;
399 
400     if (!dev->config) {
401         return NULL;
402     }
403     for (g = 0; g < dev->config->nif_groups; g++) {
404         for (i = 0; i < dev->config->if_groups[g].nif; i++) {
405             iface = &dev->config->if_groups[g].ifs[i];
406             if (iface->bInterfaceNumber == nif &&
407                 iface->bAlternateSetting == alt) {
408                 return iface;
409             }
410         }
411     }
412     for (i = 0; i < dev->config->nif; i++) {
413         iface = &dev->config->ifs[i];
414         if (iface->bInterfaceNumber == nif &&
415             iface->bAlternateSetting == alt) {
416             return iface;
417         }
418     }
419     return NULL;
420 }
421 
422 static int usb_desc_set_interface(USBDevice *dev, int index, int value)
423 {
424     const USBDescIface *iface;
425     int old;
426 
427     iface = usb_desc_find_interface(dev, index, value);
428     if (iface == NULL) {
429         return -1;
430     }
431 
432     old = dev->altsetting[index];
433     dev->altsetting[index] = value;
434     dev->ifaces[index] = iface;
435     usb_desc_ep_init(dev);
436 
437     if (old != value) {
438         usb_device_set_interface(dev, index, old, value);
439     }
440     return 0;
441 }
442 
443 static int usb_desc_set_config(USBDevice *dev, int value)
444 {
445     int i;
446 
447     if (value == 0) {
448         dev->configuration = 0;
449         dev->ninterfaces   = 0;
450         dev->config = NULL;
451     } else {
452         for (i = 0; i < dev->device->bNumConfigurations; i++) {
453             if (dev->device->confs[i].bConfigurationValue == value) {
454                 dev->configuration = value;
455                 dev->ninterfaces   = dev->device->confs[i].bNumInterfaces;
456                 dev->config = dev->device->confs + i;
457                 assert(dev->ninterfaces <= USB_MAX_INTERFACES);
458             }
459         }
460         if (i < dev->device->bNumConfigurations) {
461             return -1;
462         }
463     }
464 
465     for (i = 0; i < dev->ninterfaces; i++) {
466         usb_desc_set_interface(dev, i, 0);
467     }
468     for (; i < USB_MAX_INTERFACES; i++) {
469         dev->altsetting[i] = 0;
470         dev->ifaces[i] = NULL;
471     }
472 
473     return 0;
474 }
475 
476 static void usb_desc_setdefaults(USBDevice *dev)
477 {
478     const USBDesc *desc = usb_device_get_usb_desc(dev);
479 
480     assert(desc != NULL);
481     switch (dev->speed) {
482     case USB_SPEED_LOW:
483     case USB_SPEED_FULL:
484         dev->device = desc->full;
485         break;
486     case USB_SPEED_HIGH:
487         dev->device = desc->high;
488         break;
489     case USB_SPEED_SUPER:
490         dev->device = desc->super;
491         break;
492     }
493     usb_desc_set_config(dev, 0);
494 }
495 
496 void usb_desc_init(USBDevice *dev)
497 {
498     const USBDesc *desc = usb_device_get_usb_desc(dev);
499 
500     assert(desc != NULL);
501     dev->speed = USB_SPEED_FULL;
502     dev->speedmask = 0;
503     if (desc->full) {
504         dev->speedmask |= USB_SPEED_MASK_FULL;
505     }
506     if (desc->high) {
507         dev->speedmask |= USB_SPEED_MASK_HIGH;
508     }
509     if (desc->super) {
510         dev->speedmask |= USB_SPEED_MASK_SUPER;
511     }
512     if (desc->msos && (dev->flags & (1 << USB_DEV_FLAG_MSOS_DESC_ENABLE))) {
513         dev->flags |= (1 << USB_DEV_FLAG_MSOS_DESC_IN_USE);
514         usb_desc_set_string(dev, 0xee, "MSFT100Q");
515     }
516     usb_desc_setdefaults(dev);
517 }
518 
519 void usb_desc_attach(USBDevice *dev)
520 {
521     usb_desc_setdefaults(dev);
522 }
523 
524 void usb_desc_set_string(USBDevice *dev, uint8_t index, const char *str)
525 {
526     USBDescString *s;
527 
528     QLIST_FOREACH(s, &dev->strings, next) {
529         if (s->index == index) {
530             break;
531         }
532     }
533     if (s == NULL) {
534         s = g_malloc0(sizeof(*s));
535         s->index = index;
536         QLIST_INSERT_HEAD(&dev->strings, s, next);
537     }
538     g_free(s->str);
539     s->str = g_strdup(str);
540 }
541 
542 /*
543  * This function creates a serial number for a usb device.
544  * The serial number should:
545  *   (a) Be unique within the virtual machine.
546  *   (b) Be constant, so you don't get a new one each
547  *       time the guest is started.
548  * So we are using the physical location to generate a serial number
549  * from it.  It has three pieces:  First a fixed, device-specific
550  * prefix.  Second the device path of the host controller (which is
551  * the pci address in most cases).  Third the physical port path.
552  * Results in serial numbers like this: "314159-0000:00:1d.7-3".
553  */
554 void usb_desc_create_serial(USBDevice *dev)
555 {
556     DeviceState *hcd = dev->qdev.parent_bus->parent;
557     const USBDesc *desc = usb_device_get_usb_desc(dev);
558     int index = desc->id.iSerialNumber;
559     char *path, *serial;
560 
561     if (dev->serial) {
562         /* 'serial' usb bus property has priority if present */
563         usb_desc_set_string(dev, index, dev->serial);
564         return;
565     }
566 
567     assert(index != 0 && desc->str[index] != NULL);
568     path = qdev_get_dev_path(hcd);
569     if (path) {
570         serial = g_strdup_printf("%s-%s-%s", desc->str[index],
571                                  path, dev->port->path);
572     } else {
573         serial = g_strdup_printf("%s-%s", desc->str[index], dev->port->path);
574     }
575     usb_desc_set_string(dev, index, serial);
576     g_free(path);
577     g_free(serial);
578 }
579 
580 const char *usb_desc_get_string(USBDevice *dev, uint8_t index)
581 {
582     USBDescString *s;
583 
584     QLIST_FOREACH(s, &dev->strings, next) {
585         if (s->index == index) {
586             return s->str;
587         }
588     }
589     return NULL;
590 }
591 
592 int usb_desc_string(USBDevice *dev, int index, uint8_t *dest, size_t len)
593 {
594     uint8_t bLength, pos, i;
595     const char *str;
596 
597     if (len < 4) {
598         return -1;
599     }
600 
601     if (index == 0) {
602         /* language ids */
603         dest[0] = 4;
604         dest[1] = USB_DT_STRING;
605         dest[2] = 0x09;
606         dest[3] = 0x04;
607         return 4;
608     }
609 
610     str = usb_desc_get_string(dev, index);
611     if (str == NULL) {
612         str = usb_device_get_usb_desc(dev)->str[index];
613         if (str == NULL) {
614             return 0;
615         }
616     }
617 
618     bLength = strlen(str) * 2 + 2;
619     dest[0] = bLength;
620     dest[1] = USB_DT_STRING;
621     i = 0; pos = 2;
622     while (pos+1 < bLength && pos+1 < len) {
623         dest[pos++] = str[i++];
624         dest[pos++] = 0;
625     }
626     return pos;
627 }
628 
629 int usb_desc_get_descriptor(USBDevice *dev, USBPacket *p,
630                             int value, uint8_t *dest, size_t len)
631 {
632     bool msos = (dev->flags & (1 << USB_DEV_FLAG_MSOS_DESC_IN_USE));
633     const USBDesc *desc = usb_device_get_usb_desc(dev);
634     const USBDescDevice *other_dev;
635     size_t buflen = USB_DESC_MAX_LEN;
636     g_autofree uint8_t *buf = g_malloc(buflen);
637     uint8_t type = value >> 8;
638     uint8_t index = value & 0xff;
639     int flags, ret = -1;
640 
641     if (dev->speed == USB_SPEED_HIGH) {
642         other_dev = usb_device_get_usb_desc(dev)->full;
643     } else {
644         other_dev = usb_device_get_usb_desc(dev)->high;
645     }
646 
647     flags = 0;
648     if (dev->device->bcdUSB >= 0x0300) {
649         flags |= USB_DESC_FLAG_SUPER;
650     }
651 
652     switch(type) {
653     case USB_DT_DEVICE:
654         ret = usb_desc_device(&desc->id, dev->device, msos, buf, buflen);
655         trace_usb_desc_device(dev->addr, len, ret);
656         break;
657     case USB_DT_CONFIG:
658         if (index < dev->device->bNumConfigurations) {
659             ret = usb_desc_config(dev->device->confs + index, flags,
660                                   buf, buflen);
661         }
662         trace_usb_desc_config(dev->addr, index, len, ret);
663         break;
664     case USB_DT_STRING:
665         ret = usb_desc_string(dev, index, buf, buflen);
666         trace_usb_desc_string(dev->addr, index, len, ret);
667         break;
668     case USB_DT_DEVICE_QUALIFIER:
669         if (other_dev != NULL) {
670             ret = usb_desc_device_qualifier(other_dev, buf, buflen);
671         }
672         trace_usb_desc_device_qualifier(dev->addr, len, ret);
673         break;
674     case USB_DT_OTHER_SPEED_CONFIG:
675         if (other_dev != NULL && index < other_dev->bNumConfigurations) {
676             ret = usb_desc_config(other_dev->confs + index, flags,
677                                   buf, buflen);
678             buf[0x01] = USB_DT_OTHER_SPEED_CONFIG;
679         }
680         trace_usb_desc_other_speed_config(dev->addr, index, len, ret);
681         break;
682     case USB_DT_BOS:
683         ret = usb_desc_bos(desc, buf, buflen);
684         trace_usb_desc_bos(dev->addr, len, ret);
685         break;
686 
687     case USB_DT_DEBUG:
688         /* ignore silently */
689         break;
690 
691     default:
692         fprintf(stderr, "%s: %d unknown type %d (len %zd)\n", __func__,
693                 dev->addr, type, len);
694         break;
695     }
696 
697     if (ret > 0) {
698         if (ret > len) {
699             ret = len;
700         }
701         memcpy(dest, buf, ret);
702         p->actual_length = ret;
703         ret = 0;
704     }
705     return ret;
706 }
707 
708 int usb_desc_handle_control(USBDevice *dev, USBPacket *p,
709         int request, int value, int index, int length, uint8_t *data)
710 {
711     bool msos = (dev->flags & (1 << USB_DEV_FLAG_MSOS_DESC_IN_USE));
712     const USBDesc *desc = usb_device_get_usb_desc(dev);
713     int ret = -1;
714 
715     assert(desc != NULL);
716     switch(request) {
717     case DeviceOutRequest | USB_REQ_SET_ADDRESS:
718         dev->addr = value;
719         trace_usb_set_addr(dev->addr);
720         ret = 0;
721         break;
722 
723     case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
724         ret = usb_desc_get_descriptor(dev, p, value, data, length);
725         break;
726 
727     case DeviceRequest | USB_REQ_GET_CONFIGURATION:
728         /*
729          * 9.4.2: 0 should be returned if the device is unconfigured, otherwise
730          * the non zero value of bConfigurationValue.
731          */
732         data[0] = dev->config ? dev->config->bConfigurationValue : 0;
733         p->actual_length = 1;
734         ret = 0;
735         break;
736     case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
737         ret = usb_desc_set_config(dev, value);
738         trace_usb_set_config(dev->addr, value, ret);
739         break;
740 
741     case DeviceRequest | USB_REQ_GET_STATUS: {
742         const USBDescConfig *config = dev->config ?
743             dev->config : &dev->device->confs[0];
744 
745         data[0] = 0;
746         /*
747          * Default state: Device behavior when this request is received while
748          *                the device is in the Default state is not specified.
749          * We return the same value that a configured device would return if
750          * it used the first configuration.
751          */
752         if (config->bmAttributes & USB_CFG_ATT_SELFPOWER) {
753             data[0] |= 1 << USB_DEVICE_SELF_POWERED;
754         }
755         if (dev->remote_wakeup) {
756             data[0] |= 1 << USB_DEVICE_REMOTE_WAKEUP;
757         }
758         data[1] = 0x00;
759         p->actual_length = 2;
760         ret = 0;
761         break;
762     }
763     case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
764         if (value == USB_DEVICE_REMOTE_WAKEUP) {
765             dev->remote_wakeup = 0;
766             ret = 0;
767         }
768         trace_usb_clear_device_feature(dev->addr, value, ret);
769         break;
770     case DeviceOutRequest | USB_REQ_SET_FEATURE:
771         if (value == USB_DEVICE_REMOTE_WAKEUP) {
772             dev->remote_wakeup = 1;
773             ret = 0;
774         }
775         trace_usb_set_device_feature(dev->addr, value, ret);
776         break;
777 
778     case DeviceOutRequest | USB_REQ_SET_SEL:
779     case DeviceOutRequest | USB_REQ_SET_ISOCH_DELAY:
780         if (dev->speed == USB_SPEED_SUPER) {
781             ret = 0;
782         }
783         break;
784 
785     case InterfaceRequest | USB_REQ_GET_INTERFACE:
786         if (index < 0 || index >= dev->ninterfaces) {
787             break;
788         }
789         data[0] = dev->altsetting[index];
790         p->actual_length = 1;
791         ret = 0;
792         break;
793     case InterfaceOutRequest | USB_REQ_SET_INTERFACE:
794         ret = usb_desc_set_interface(dev, index, value);
795         trace_usb_set_interface(dev->addr, index, value, ret);
796         break;
797 
798     case VendorDeviceRequest | 'Q':
799         if (msos) {
800             ret = usb_desc_msos(desc, p, index, data, length);
801             trace_usb_desc_msos(dev->addr, index, length, ret);
802         }
803         break;
804     case VendorInterfaceRequest | 'Q':
805         if (msos) {
806             ret = usb_desc_msos(desc, p, index, data, length);
807             trace_usb_desc_msos(dev->addr, index, length, ret);
808         }
809         break;
810 
811     }
812     return ret;
813 }
814