xref: /openbmc/qemu/hw/usb/desc.c (revision 878096ee)
1 #include <ctype.h>
2 
3 #include "hw/usb.h"
4 #include "hw/usb/desc.h"
5 #include "trace.h"
6 
7 /* ------------------------------------------------------------------ */
8 
9 static uint8_t usb_lo(uint16_t val)
10 {
11     return val & 0xff;
12 }
13 
14 static uint8_t usb_hi(uint16_t val)
15 {
16     return (val >> 8) & 0xff;
17 }
18 
19 int usb_desc_device(const USBDescID *id, const USBDescDevice *dev,
20                     uint8_t *dest, size_t len)
21 {
22     uint8_t bLength = 0x12;
23     USBDescriptor *d = (void *)dest;
24 
25     if (len < bLength) {
26         return -1;
27     }
28 
29     d->bLength                     = bLength;
30     d->bDescriptorType             = USB_DT_DEVICE;
31 
32     d->u.device.bcdUSB_lo          = usb_lo(dev->bcdUSB);
33     d->u.device.bcdUSB_hi          = usb_hi(dev->bcdUSB);
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         USBDescriptor *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         }
389     }
390 }
391 
392 static const USBDescIface *usb_desc_find_interface(USBDevice *dev,
393                                                    int nif, int alt)
394 {
395     const USBDescIface *iface;
396     int g, i;
397 
398     if (!dev->config) {
399         return NULL;
400     }
401     for (g = 0; g < dev->config->nif_groups; g++) {
402         for (i = 0; i < dev->config->if_groups[g].nif; i++) {
403             iface = &dev->config->if_groups[g].ifs[i];
404             if (iface->bInterfaceNumber == nif &&
405                 iface->bAlternateSetting == alt) {
406                 return iface;
407             }
408         }
409     }
410     for (i = 0; i < dev->config->nif; i++) {
411         iface = &dev->config->ifs[i];
412         if (iface->bInterfaceNumber == nif &&
413             iface->bAlternateSetting == alt) {
414             return iface;
415         }
416     }
417     return NULL;
418 }
419 
420 static int usb_desc_set_interface(USBDevice *dev, int index, int value)
421 {
422     const USBDescIface *iface;
423     int old;
424 
425     iface = usb_desc_find_interface(dev, index, value);
426     if (iface == NULL) {
427         return -1;
428     }
429 
430     old = dev->altsetting[index];
431     dev->altsetting[index] = value;
432     dev->ifaces[index] = iface;
433     usb_desc_ep_init(dev);
434 
435     if (old != value) {
436         usb_device_set_interface(dev, index, old, value);
437     }
438     return 0;
439 }
440 
441 static int usb_desc_set_config(USBDevice *dev, int value)
442 {
443     int i;
444 
445     if (value == 0) {
446         dev->configuration = 0;
447         dev->ninterfaces   = 0;
448         dev->config = NULL;
449     } else {
450         for (i = 0; i < dev->device->bNumConfigurations; i++) {
451             if (dev->device->confs[i].bConfigurationValue == value) {
452                 dev->configuration = value;
453                 dev->ninterfaces   = dev->device->confs[i].bNumInterfaces;
454                 dev->config = dev->device->confs + i;
455                 assert(dev->ninterfaces <= USB_MAX_INTERFACES);
456             }
457         }
458         if (i < dev->device->bNumConfigurations) {
459             return -1;
460         }
461     }
462 
463     for (i = 0; i < dev->ninterfaces; i++) {
464         usb_desc_set_interface(dev, i, 0);
465     }
466     for (; i < USB_MAX_INTERFACES; i++) {
467         dev->altsetting[i] = 0;
468         dev->ifaces[i] = NULL;
469     }
470 
471     return 0;
472 }
473 
474 static void usb_desc_setdefaults(USBDevice *dev)
475 {
476     const USBDesc *desc = usb_device_get_usb_desc(dev);
477 
478     assert(desc != NULL);
479     switch (dev->speed) {
480     case USB_SPEED_LOW:
481     case USB_SPEED_FULL:
482         dev->device = desc->full;
483         break;
484     case USB_SPEED_HIGH:
485         dev->device = desc->high;
486         break;
487     case USB_SPEED_SUPER:
488         dev->device = desc->super;
489         break;
490     }
491     usb_desc_set_config(dev, 0);
492 }
493 
494 void usb_desc_init(USBDevice *dev)
495 {
496     const USBDesc *desc = usb_device_get_usb_desc(dev);
497 
498     assert(desc != NULL);
499     dev->speed = USB_SPEED_FULL;
500     dev->speedmask = 0;
501     if (desc->full) {
502         dev->speedmask |= USB_SPEED_MASK_FULL;
503     }
504     if (desc->high) {
505         dev->speedmask |= USB_SPEED_MASK_HIGH;
506     }
507     if (desc->super) {
508         dev->speedmask |= USB_SPEED_MASK_SUPER;
509     }
510     usb_desc_setdefaults(dev);
511 }
512 
513 void usb_desc_attach(USBDevice *dev)
514 {
515     const USBDesc *desc = usb_device_get_usb_desc(dev);
516 
517     assert(desc != NULL);
518     if (desc->super && (dev->port->speedmask & USB_SPEED_MASK_SUPER)) {
519         dev->speed = USB_SPEED_SUPER;
520     } else if (desc->high && (dev->port->speedmask & USB_SPEED_MASK_HIGH)) {
521         dev->speed = USB_SPEED_HIGH;
522     } else if (desc->full && (dev->port->speedmask & USB_SPEED_MASK_FULL)) {
523         dev->speed = USB_SPEED_FULL;
524     } else {
525         return;
526     }
527     usb_desc_setdefaults(dev);
528 }
529 
530 void usb_desc_set_string(USBDevice *dev, uint8_t index, const char *str)
531 {
532     USBDescString *s;
533 
534     QLIST_FOREACH(s, &dev->strings, next) {
535         if (s->index == index) {
536             break;
537         }
538     }
539     if (s == NULL) {
540         s = g_malloc0(sizeof(*s));
541         s->index = index;
542         QLIST_INSERT_HEAD(&dev->strings, s, next);
543     }
544     g_free(s->str);
545     s->str = g_strdup(str);
546 }
547 
548 /*
549  * This function creates a serial number for a usb device.
550  * The serial number should:
551  *   (a) Be unique within the virtual machine.
552  *   (b) Be constant, so you don't get a new one each
553  *       time the guest is started.
554  * So we are using the physical location to generate a serial number
555  * from it.  It has three pieces:  First a fixed, device-specific
556  * prefix.  Second the device path of the host controller (which is
557  * the pci address in most cases).  Third the physical port path.
558  * Results in serial numbers like this: "314159-0000:00:1d.7-3".
559  */
560 void usb_desc_create_serial(USBDevice *dev)
561 {
562     DeviceState *hcd = dev->qdev.parent_bus->parent;
563     const USBDesc *desc = usb_device_get_usb_desc(dev);
564     int index = desc->id.iSerialNumber;
565     char serial[64];
566     char *path;
567     int dst;
568 
569     if (dev->serial) {
570         /* 'serial' usb bus property has priority if present */
571         usb_desc_set_string(dev, index, dev->serial);
572         return;
573     }
574 
575     assert(index != 0 && desc->str[index] != NULL);
576     dst = snprintf(serial, sizeof(serial), "%s", desc->str[index]);
577     path = qdev_get_dev_path(hcd);
578     if (path) {
579         dst += snprintf(serial+dst, sizeof(serial)-dst, "-%s", path);
580     }
581     dst += snprintf(serial+dst, sizeof(serial)-dst, "-%s", dev->port->path);
582     usb_desc_set_string(dev, index, serial);
583 }
584 
585 const char *usb_desc_get_string(USBDevice *dev, uint8_t index)
586 {
587     USBDescString *s;
588 
589     QLIST_FOREACH(s, &dev->strings, next) {
590         if (s->index == index) {
591             return s->str;
592         }
593     }
594     return NULL;
595 }
596 
597 int usb_desc_string(USBDevice *dev, int index, uint8_t *dest, size_t len)
598 {
599     uint8_t bLength, pos, i;
600     const char *str;
601 
602     if (len < 4) {
603         return -1;
604     }
605 
606     if (index == 0) {
607         /* language ids */
608         dest[0] = 4;
609         dest[1] = USB_DT_STRING;
610         dest[2] = 0x09;
611         dest[3] = 0x04;
612         return 4;
613     }
614 
615     str = usb_desc_get_string(dev, index);
616     if (str == NULL) {
617         str = usb_device_get_usb_desc(dev)->str[index];
618         if (str == NULL) {
619             return 0;
620         }
621     }
622 
623     bLength = strlen(str) * 2 + 2;
624     dest[0] = bLength;
625     dest[1] = USB_DT_STRING;
626     i = 0; pos = 2;
627     while (pos+1 < bLength && pos+1 < len) {
628         dest[pos++] = str[i++];
629         dest[pos++] = 0;
630     }
631     return pos;
632 }
633 
634 int usb_desc_get_descriptor(USBDevice *dev, USBPacket *p,
635                             int value, uint8_t *dest, size_t len)
636 {
637     const USBDesc *desc = usb_device_get_usb_desc(dev);
638     const USBDescDevice *other_dev;
639     uint8_t buf[256];
640     uint8_t type = value >> 8;
641     uint8_t index = value & 0xff;
642     int flags, ret = -1;
643 
644     if (dev->speed == USB_SPEED_HIGH) {
645         other_dev = usb_device_get_usb_desc(dev)->full;
646     } else {
647         other_dev = usb_device_get_usb_desc(dev)->high;
648     }
649 
650     flags = 0;
651     if (dev->device->bcdUSB >= 0x0300) {
652         flags |= USB_DESC_FLAG_SUPER;
653     }
654 
655     switch(type) {
656     case USB_DT_DEVICE:
657         ret = usb_desc_device(&desc->id, dev->device, buf, sizeof(buf));
658         trace_usb_desc_device(dev->addr, len, ret);
659         break;
660     case USB_DT_CONFIG:
661         if (index < dev->device->bNumConfigurations) {
662             ret = usb_desc_config(dev->device->confs + index, flags,
663                                   buf, sizeof(buf));
664         }
665         trace_usb_desc_config(dev->addr, index, len, ret);
666         break;
667     case USB_DT_STRING:
668         ret = usb_desc_string(dev, index, buf, sizeof(buf));
669         trace_usb_desc_string(dev->addr, index, len, ret);
670         break;
671     case USB_DT_DEVICE_QUALIFIER:
672         if (other_dev != NULL) {
673             ret = usb_desc_device_qualifier(other_dev, buf, sizeof(buf));
674         }
675         trace_usb_desc_device_qualifier(dev->addr, len, ret);
676         break;
677     case USB_DT_OTHER_SPEED_CONFIG:
678         if (other_dev != NULL && index < other_dev->bNumConfigurations) {
679             ret = usb_desc_config(other_dev->confs + index, flags,
680                                   buf, sizeof(buf));
681             buf[0x01] = USB_DT_OTHER_SPEED_CONFIG;
682         }
683         trace_usb_desc_other_speed_config(dev->addr, index, len, ret);
684         break;
685     case USB_DT_BOS:
686         ret = usb_desc_bos(desc, buf, sizeof(buf));
687         trace_usb_desc_bos(dev->addr, len, ret);
688         break;
689 
690     case USB_DT_DEBUG:
691         /* ignore silently */
692         break;
693 
694     default:
695         fprintf(stderr, "%s: %d unknown type %d (len %zd)\n", __FUNCTION__,
696                 dev->addr, type, len);
697         break;
698     }
699 
700     if (ret > 0) {
701         if (ret > len) {
702             ret = len;
703         }
704         memcpy(dest, buf, ret);
705         p->actual_length = ret;
706         ret = 0;
707     }
708     return ret;
709 }
710 
711 int usb_desc_handle_control(USBDevice *dev, USBPacket *p,
712         int request, int value, int index, int length, uint8_t *data)
713 {
714     const USBDesc *desc = usb_device_get_usb_desc(dev);
715     int ret = -1;
716 
717     assert(desc != NULL);
718     switch(request) {
719     case DeviceOutRequest | USB_REQ_SET_ADDRESS:
720         dev->addr = value;
721         trace_usb_set_addr(dev->addr);
722         ret = 0;
723         break;
724 
725     case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
726         ret = usb_desc_get_descriptor(dev, p, value, data, length);
727         break;
728 
729     case DeviceRequest | USB_REQ_GET_CONFIGURATION:
730         /*
731          * 9.4.2: 0 should be returned if the device is unconfigured, otherwise
732          * the non zero value of bConfigurationValue.
733          */
734         data[0] = dev->config ? dev->config->bConfigurationValue : 0;
735         p->actual_length = 1;
736         ret = 0;
737         break;
738     case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
739         ret = usb_desc_set_config(dev, value);
740         trace_usb_set_config(dev->addr, value, ret);
741         break;
742 
743     case DeviceRequest | USB_REQ_GET_STATUS: {
744         const USBDescConfig *config = dev->config ?
745             dev->config : &dev->device->confs[0];
746 
747         data[0] = 0;
748         /*
749          * Default state: Device behavior when this request is received while
750          *                the device is in the Default state is not specified.
751          * We return the same value that a configured device would return if
752          * it used the first configuration.
753          */
754         if (config->bmAttributes & 0x40) {
755             data[0] |= 1 << USB_DEVICE_SELF_POWERED;
756         }
757         if (dev->remote_wakeup) {
758             data[0] |= 1 << USB_DEVICE_REMOTE_WAKEUP;
759         }
760         data[1] = 0x00;
761         p->actual_length = 2;
762         ret = 0;
763         break;
764     }
765     case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
766         if (value == USB_DEVICE_REMOTE_WAKEUP) {
767             dev->remote_wakeup = 0;
768             ret = 0;
769         }
770         trace_usb_clear_device_feature(dev->addr, value, ret);
771         break;
772     case DeviceOutRequest | USB_REQ_SET_FEATURE:
773         if (value == USB_DEVICE_REMOTE_WAKEUP) {
774             dev->remote_wakeup = 1;
775             ret = 0;
776         }
777         trace_usb_set_device_feature(dev->addr, value, ret);
778         break;
779 
780     case InterfaceRequest | USB_REQ_GET_INTERFACE:
781         if (index < 0 || index >= dev->ninterfaces) {
782             break;
783         }
784         data[0] = dev->altsetting[index];
785         p->actual_length = 1;
786         ret = 0;
787         break;
788     case InterfaceOutRequest | USB_REQ_SET_INTERFACE:
789         ret = usb_desc_set_interface(dev, index, value);
790         trace_usb_set_interface(dev->addr, index, value, ret);
791         break;
792 
793     }
794     return ret;
795 }
796