1/* $FreeBSD: head/lib/libusb/libusb10_desc.c 199055 2009-11-08 20:03:52Z thompsa $ */
2/*-
3 * Copyright (c) 2009 Sylvestre Gallon. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <stdlib.h>
28#include <stdio.h>
29#include <pthread.h>
30#include <sys/queue.h>
31
32#include "libusb20.h"
33#include "libusb20_desc.h"
34#include "libusb20_int.h"
35#include "libusb.h"
36#include "libusb10.h"
37
38#define N_ALIGN(n) (-((-(n)) & (-8UL)))
39
40/* USB descriptors */
41
42int
43libusb_get_device_descriptor(libusb_device *dev,
44 struct libusb_device_descriptor *desc)
45{
46 struct LIBUSB20_DEVICE_DESC_DECODED *pdesc;
47 struct libusb20_device *pdev;
48
49 if ((dev == NULL) || (desc == NULL))
50 return (LIBUSB_ERROR_INVALID_PARAM);
51
52 pdev = dev->os_priv;
53 pdesc = libusb20_dev_get_device_desc(pdev);
54
55 desc->bLength = pdesc->bLength;
56 desc->bDescriptorType = pdesc->bDescriptorType;
57 desc->bcdUSB = pdesc->bcdUSB;
58 desc->bDeviceClass = pdesc->bDeviceClass;
59 desc->bDeviceSubClass = pdesc->bDeviceSubClass;
60 desc->bDeviceProtocol = pdesc->bDeviceProtocol;
61 desc->bMaxPacketSize0 = pdesc->bMaxPacketSize0;
62 desc->idVendor = pdesc->idVendor;
63 desc->idProduct = pdesc->idProduct;
64 desc->bcdDevice = pdesc->bcdDevice;
65 desc->iManufacturer = pdesc->iManufacturer;
66 desc->iProduct = pdesc->iProduct;
67 desc->iSerialNumber = pdesc->iSerialNumber;
68 desc->bNumConfigurations = pdesc->bNumConfigurations;
69
70 return (0);
71}
72
73int
74libusb_get_active_config_descriptor(libusb_device *dev,
75 struct libusb_config_descriptor **config)
76{
77 struct libusb20_device *pdev;
78 uint8_t config_index;
79
80 pdev = dev->os_priv;
81 config_index = libusb20_dev_get_config_index(pdev);
82
83 return (libusb_get_config_descriptor(dev, config_index, config));
84}
85
86int
87libusb_get_config_descriptor(libusb_device *dev, uint8_t config_index,
88 struct libusb_config_descriptor **config)
89{
90 struct libusb20_device *pdev;
91 struct libusb20_config *pconf;
92 struct libusb20_interface *pinf;
93 struct libusb20_endpoint *pend;
94 struct libusb_config_descriptor *pconfd;
95 struct libusb_interface_descriptor *ifd;
96 struct libusb_endpoint_descriptor *endd;
97 uint8_t *pextra;
98 uint16_t nextra;
99 uint8_t nif;
100 uint8_t nep;
101 uint8_t nalt;
102 uint8_t i;
103 uint8_t j;
104 uint8_t k;
105
106 if (dev == NULL || config == NULL)
107 return (LIBUSB_ERROR_INVALID_PARAM);
108
109 *config = NULL;
110
111 pdev = dev->os_priv;
112 pconf = libusb20_dev_alloc_config(pdev, config_index);
113
114 if (pconf == NULL)
115 return (LIBUSB_ERROR_NOT_FOUND);
116
117 nalt = nif = pconf->num_interface;
118 nep = 0;
119 nextra = N_ALIGN(pconf->extra.len);
120
121 for (i = 0; i < nif; i++) {
122
123 pinf = pconf->interface + i;
124 nextra += N_ALIGN(pinf->extra.len);
125 nep += pinf->num_endpoints;
126 k = pinf->num_endpoints;
127 pend = pinf->endpoints;
128 while (k--) {
129 nextra += N_ALIGN(pend->extra.len);
130 pend++;
131 }
132
133 j = pinf->num_altsetting;
134 nalt += pinf->num_altsetting;
135 pinf = pinf->altsetting;
136 while (j--) {
137 nextra += N_ALIGN(pinf->extra.len);
138 nep += pinf->num_endpoints;
139 k = pinf->num_endpoints;
140 pend = pinf->endpoints;
141 while (k--) {
142 nextra += N_ALIGN(pend->extra.len);
143 pend++;
144 }
145 pinf++;
146 }
147 }
148
149 nextra = nextra +
150 (1 * sizeof(libusb_config_descriptor)) +
151 (nif * sizeof(libusb_interface)) +
152 (nalt * sizeof(libusb_interface_descriptor)) +
153 (nep * sizeof(libusb_endpoint_descriptor));
154
155 nextra = N_ALIGN(nextra);
156
157 pconfd = malloc(nextra);
158
159 if (pconfd == NULL) {
160 free(pconf);
161 return (LIBUSB_ERROR_NO_MEM);
162 }
163 /* make sure memory is initialised */
164 memset(pconfd, 0, nextra);
165
166 pconfd->interface = (libusb_interface *) (pconfd + 1);
167
168 ifd = (libusb_interface_descriptor *) (pconfd->interface + nif);
169 endd = (libusb_endpoint_descriptor *) (ifd + nalt);
170 pextra = (uint8_t *)(endd + nep);
171
172 /* fill in config descriptor */
173
174 pconfd->bLength = pconf->desc.bLength;
175 pconfd->bDescriptorType = pconf->desc.bDescriptorType;
176 pconfd->wTotalLength = pconf->desc.wTotalLength;
177 pconfd->bNumInterfaces = pconf->desc.bNumInterfaces;
178 pconfd->bConfigurationValue = pconf->desc.bConfigurationValue;
179 pconfd->iConfiguration = pconf->desc.iConfiguration;
180 pconfd->bmAttributes = pconf->desc.bmAttributes;
181 pconfd->MaxPower = pconf->desc.bMaxPower;
182
183 if (pconf->extra.len != 0) {
184 pconfd->extra_length = pconf->extra.len;
185 pconfd->extra = pextra;
186 memcpy(pextra, pconf->extra.ptr, pconfd->extra_length);
187 pextra += N_ALIGN(pconfd->extra_length);
188 }
189 /* setup all interface and endpoint pointers */
190
191 for (i = 0; i < nif; i++) {
192
193 pconfd->interface[i].altsetting = ifd;
194 ifd->endpoint = endd;
195 endd += pconf->interface[i].num_endpoints;
196 ifd++;
197
198 for (j = 0; j < pconf->interface[i].num_altsetting; j++) {
199 ifd->endpoint = endd;
200 endd += pconf->interface[i].altsetting[j].num_endpoints;
201 ifd++;
202 }
203 }
204
205 /* fill in all interface and endpoint data */
206
207 for (i = 0; i < nif; i++) {
208 pinf = &pconf->interface[i];
209 pconfd->interface[i].num_altsetting = pinf->num_altsetting + 1;
210 for (j = 0; j < pconfd->interface[i].num_altsetting; j++) {
211 if (j != 0)
212 pinf = &pconf->interface[i].altsetting[j - 1];
213 ifd = &pconfd->interface[i].altsetting[j];
214 ifd->bLength = pinf->desc.bLength;
215 ifd->bDescriptorType = pinf->desc.bDescriptorType;
216 ifd->bInterfaceNumber = pinf->desc.bInterfaceNumber;
217 ifd->bAlternateSetting = pinf->desc.bAlternateSetting;
218 ifd->bNumEndpoints = pinf->desc.bNumEndpoints;
219 ifd->bInterfaceClass = pinf->desc.bInterfaceClass;
220 ifd->bInterfaceSubClass = pinf->desc.bInterfaceSubClass;
221 ifd->bInterfaceProtocol = pinf->desc.bInterfaceProtocol;
222 ifd->iInterface = pinf->desc.iInterface;
223 if (pinf->extra.len != 0) {
224 ifd->extra_length = pinf->extra.len;
225 ifd->extra = pextra;
226 memcpy(pextra, pinf->extra.ptr, pinf->extra.len);
227 pextra += N_ALIGN(pinf->extra.len);
228 }
229 for (k = 0; k < pinf->num_endpoints; k++) {
230 pend = &pinf->endpoints[k];
231 endd = &ifd->endpoint[k];
232 endd->bLength = pend->desc.bLength;
233 endd->bDescriptorType = pend->desc.bDescriptorType;
234 endd->bEndpointAddress = pend->desc.bEndpointAddress;
235 endd->bmAttributes = pend->desc.bmAttributes;
236 endd->wMaxPacketSize = pend->desc.wMaxPacketSize;
237 endd->bInterval = pend->desc.bInterval;
238 endd->bRefresh = pend->desc.bRefresh;
239 endd->bSynchAddress = pend->desc.bSynchAddress;
240 if (pend->extra.len != 0) {
241 endd->extra_length = pend->extra.len;
242 endd->extra = pextra;
243 memcpy(pextra, pend->extra.ptr, pend->extra.len);
244 pextra += N_ALIGN(pend->extra.len);
245 }
246 }
247 }
248 }
249
250 free(pconf);
251
252 *config = pconfd;
253
254 return (0); /* success */
255}
256
257int
258libusb_get_config_descriptor_by_value(libusb_device *dev,
259 uint8_t bConfigurationValue, struct libusb_config_descriptor **config)
260{
261 struct LIBUSB20_DEVICE_DESC_DECODED *pdesc;
262 struct libusb20_device *pdev;
263 int i;
264 int err;
265
266 if (dev == NULL || config == NULL)
267 return (LIBUSB_ERROR_INVALID_PARAM);
268
269 pdev = dev->os_priv;
270 pdesc = libusb20_dev_get_device_desc(pdev);
271
272 for (i = 0; i < pdesc->bNumConfigurations; i++) {
273 err = libusb_get_config_descriptor(dev, i, config);
274 if (err)
275 return (err);
276
277 if ((*config)->bConfigurationValue == bConfigurationValue)
278 return (0); /* success */
279
280 libusb_free_config_descriptor(*config);
281 }
282
283 *config = NULL;
284
285 return (LIBUSB_ERROR_NOT_FOUND);
286}
287
288void
289libusb_free_config_descriptor(struct libusb_config_descriptor *config)
290{
291 free(config);
292}
293
294int
295libusb_get_string_descriptor_ascii(libusb_device_handle *pdev,
296 uint8_t desc_index, unsigned char *data, int length)
297{
298 if (pdev == NULL || data == NULL || length < 1)
299 return (LIBUSB20_ERROR_INVALID_PARAM);
300
301 /* put some default data into the destination buffer */
302 data[0] = 0;
303
304 if (libusb20_dev_req_string_simple_sync(pdev, desc_index,
305 data, length) == 0)
306 return (strlen(data));
307
308 return (LIBUSB_ERROR_OTHER);
309}
310
311int
312libusb_get_descriptor(libusb_device_handle * devh, uint8_t desc_type,
313 uint8_t desc_index, uint8_t *data, int length)
314{
315 return (libusb_control_transfer(devh, LIBUSB_ENDPOINT_IN,
316 LIBUSB_REQUEST_GET_DESCRIPTOR, (desc_type << 8) | desc_index, 0, data,
317 length, 1000));
318}
2/*-
3 * Copyright (c) 2009 Sylvestre Gallon. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <stdlib.h>
28#include <stdio.h>
29#include <pthread.h>
30#include <sys/queue.h>
31
32#include "libusb20.h"
33#include "libusb20_desc.h"
34#include "libusb20_int.h"
35#include "libusb.h"
36#include "libusb10.h"
37
38#define N_ALIGN(n) (-((-(n)) & (-8UL)))
39
40/* USB descriptors */
41
42int
43libusb_get_device_descriptor(libusb_device *dev,
44 struct libusb_device_descriptor *desc)
45{
46 struct LIBUSB20_DEVICE_DESC_DECODED *pdesc;
47 struct libusb20_device *pdev;
48
49 if ((dev == NULL) || (desc == NULL))
50 return (LIBUSB_ERROR_INVALID_PARAM);
51
52 pdev = dev->os_priv;
53 pdesc = libusb20_dev_get_device_desc(pdev);
54
55 desc->bLength = pdesc->bLength;
56 desc->bDescriptorType = pdesc->bDescriptorType;
57 desc->bcdUSB = pdesc->bcdUSB;
58 desc->bDeviceClass = pdesc->bDeviceClass;
59 desc->bDeviceSubClass = pdesc->bDeviceSubClass;
60 desc->bDeviceProtocol = pdesc->bDeviceProtocol;
61 desc->bMaxPacketSize0 = pdesc->bMaxPacketSize0;
62 desc->idVendor = pdesc->idVendor;
63 desc->idProduct = pdesc->idProduct;
64 desc->bcdDevice = pdesc->bcdDevice;
65 desc->iManufacturer = pdesc->iManufacturer;
66 desc->iProduct = pdesc->iProduct;
67 desc->iSerialNumber = pdesc->iSerialNumber;
68 desc->bNumConfigurations = pdesc->bNumConfigurations;
69
70 return (0);
71}
72
73int
74libusb_get_active_config_descriptor(libusb_device *dev,
75 struct libusb_config_descriptor **config)
76{
77 struct libusb20_device *pdev;
78 uint8_t config_index;
79
80 pdev = dev->os_priv;
81 config_index = libusb20_dev_get_config_index(pdev);
82
83 return (libusb_get_config_descriptor(dev, config_index, config));
84}
85
86int
87libusb_get_config_descriptor(libusb_device *dev, uint8_t config_index,
88 struct libusb_config_descriptor **config)
89{
90 struct libusb20_device *pdev;
91 struct libusb20_config *pconf;
92 struct libusb20_interface *pinf;
93 struct libusb20_endpoint *pend;
94 struct libusb_config_descriptor *pconfd;
95 struct libusb_interface_descriptor *ifd;
96 struct libusb_endpoint_descriptor *endd;
97 uint8_t *pextra;
98 uint16_t nextra;
99 uint8_t nif;
100 uint8_t nep;
101 uint8_t nalt;
102 uint8_t i;
103 uint8_t j;
104 uint8_t k;
105
106 if (dev == NULL || config == NULL)
107 return (LIBUSB_ERROR_INVALID_PARAM);
108
109 *config = NULL;
110
111 pdev = dev->os_priv;
112 pconf = libusb20_dev_alloc_config(pdev, config_index);
113
114 if (pconf == NULL)
115 return (LIBUSB_ERROR_NOT_FOUND);
116
117 nalt = nif = pconf->num_interface;
118 nep = 0;
119 nextra = N_ALIGN(pconf->extra.len);
120
121 for (i = 0; i < nif; i++) {
122
123 pinf = pconf->interface + i;
124 nextra += N_ALIGN(pinf->extra.len);
125 nep += pinf->num_endpoints;
126 k = pinf->num_endpoints;
127 pend = pinf->endpoints;
128 while (k--) {
129 nextra += N_ALIGN(pend->extra.len);
130 pend++;
131 }
132
133 j = pinf->num_altsetting;
134 nalt += pinf->num_altsetting;
135 pinf = pinf->altsetting;
136 while (j--) {
137 nextra += N_ALIGN(pinf->extra.len);
138 nep += pinf->num_endpoints;
139 k = pinf->num_endpoints;
140 pend = pinf->endpoints;
141 while (k--) {
142 nextra += N_ALIGN(pend->extra.len);
143 pend++;
144 }
145 pinf++;
146 }
147 }
148
149 nextra = nextra +
150 (1 * sizeof(libusb_config_descriptor)) +
151 (nif * sizeof(libusb_interface)) +
152 (nalt * sizeof(libusb_interface_descriptor)) +
153 (nep * sizeof(libusb_endpoint_descriptor));
154
155 nextra = N_ALIGN(nextra);
156
157 pconfd = malloc(nextra);
158
159 if (pconfd == NULL) {
160 free(pconf);
161 return (LIBUSB_ERROR_NO_MEM);
162 }
163 /* make sure memory is initialised */
164 memset(pconfd, 0, nextra);
165
166 pconfd->interface = (libusb_interface *) (pconfd + 1);
167
168 ifd = (libusb_interface_descriptor *) (pconfd->interface + nif);
169 endd = (libusb_endpoint_descriptor *) (ifd + nalt);
170 pextra = (uint8_t *)(endd + nep);
171
172 /* fill in config descriptor */
173
174 pconfd->bLength = pconf->desc.bLength;
175 pconfd->bDescriptorType = pconf->desc.bDescriptorType;
176 pconfd->wTotalLength = pconf->desc.wTotalLength;
177 pconfd->bNumInterfaces = pconf->desc.bNumInterfaces;
178 pconfd->bConfigurationValue = pconf->desc.bConfigurationValue;
179 pconfd->iConfiguration = pconf->desc.iConfiguration;
180 pconfd->bmAttributes = pconf->desc.bmAttributes;
181 pconfd->MaxPower = pconf->desc.bMaxPower;
182
183 if (pconf->extra.len != 0) {
184 pconfd->extra_length = pconf->extra.len;
185 pconfd->extra = pextra;
186 memcpy(pextra, pconf->extra.ptr, pconfd->extra_length);
187 pextra += N_ALIGN(pconfd->extra_length);
188 }
189 /* setup all interface and endpoint pointers */
190
191 for (i = 0; i < nif; i++) {
192
193 pconfd->interface[i].altsetting = ifd;
194 ifd->endpoint = endd;
195 endd += pconf->interface[i].num_endpoints;
196 ifd++;
197
198 for (j = 0; j < pconf->interface[i].num_altsetting; j++) {
199 ifd->endpoint = endd;
200 endd += pconf->interface[i].altsetting[j].num_endpoints;
201 ifd++;
202 }
203 }
204
205 /* fill in all interface and endpoint data */
206
207 for (i = 0; i < nif; i++) {
208 pinf = &pconf->interface[i];
209 pconfd->interface[i].num_altsetting = pinf->num_altsetting + 1;
210 for (j = 0; j < pconfd->interface[i].num_altsetting; j++) {
211 if (j != 0)
212 pinf = &pconf->interface[i].altsetting[j - 1];
213 ifd = &pconfd->interface[i].altsetting[j];
214 ifd->bLength = pinf->desc.bLength;
215 ifd->bDescriptorType = pinf->desc.bDescriptorType;
216 ifd->bInterfaceNumber = pinf->desc.bInterfaceNumber;
217 ifd->bAlternateSetting = pinf->desc.bAlternateSetting;
218 ifd->bNumEndpoints = pinf->desc.bNumEndpoints;
219 ifd->bInterfaceClass = pinf->desc.bInterfaceClass;
220 ifd->bInterfaceSubClass = pinf->desc.bInterfaceSubClass;
221 ifd->bInterfaceProtocol = pinf->desc.bInterfaceProtocol;
222 ifd->iInterface = pinf->desc.iInterface;
223 if (pinf->extra.len != 0) {
224 ifd->extra_length = pinf->extra.len;
225 ifd->extra = pextra;
226 memcpy(pextra, pinf->extra.ptr, pinf->extra.len);
227 pextra += N_ALIGN(pinf->extra.len);
228 }
229 for (k = 0; k < pinf->num_endpoints; k++) {
230 pend = &pinf->endpoints[k];
231 endd = &ifd->endpoint[k];
232 endd->bLength = pend->desc.bLength;
233 endd->bDescriptorType = pend->desc.bDescriptorType;
234 endd->bEndpointAddress = pend->desc.bEndpointAddress;
235 endd->bmAttributes = pend->desc.bmAttributes;
236 endd->wMaxPacketSize = pend->desc.wMaxPacketSize;
237 endd->bInterval = pend->desc.bInterval;
238 endd->bRefresh = pend->desc.bRefresh;
239 endd->bSynchAddress = pend->desc.bSynchAddress;
240 if (pend->extra.len != 0) {
241 endd->extra_length = pend->extra.len;
242 endd->extra = pextra;
243 memcpy(pextra, pend->extra.ptr, pend->extra.len);
244 pextra += N_ALIGN(pend->extra.len);
245 }
246 }
247 }
248 }
249
250 free(pconf);
251
252 *config = pconfd;
253
254 return (0); /* success */
255}
256
257int
258libusb_get_config_descriptor_by_value(libusb_device *dev,
259 uint8_t bConfigurationValue, struct libusb_config_descriptor **config)
260{
261 struct LIBUSB20_DEVICE_DESC_DECODED *pdesc;
262 struct libusb20_device *pdev;
263 int i;
264 int err;
265
266 if (dev == NULL || config == NULL)
267 return (LIBUSB_ERROR_INVALID_PARAM);
268
269 pdev = dev->os_priv;
270 pdesc = libusb20_dev_get_device_desc(pdev);
271
272 for (i = 0; i < pdesc->bNumConfigurations; i++) {
273 err = libusb_get_config_descriptor(dev, i, config);
274 if (err)
275 return (err);
276
277 if ((*config)->bConfigurationValue == bConfigurationValue)
278 return (0); /* success */
279
280 libusb_free_config_descriptor(*config);
281 }
282
283 *config = NULL;
284
285 return (LIBUSB_ERROR_NOT_FOUND);
286}
287
288void
289libusb_free_config_descriptor(struct libusb_config_descriptor *config)
290{
291 free(config);
292}
293
294int
295libusb_get_string_descriptor_ascii(libusb_device_handle *pdev,
296 uint8_t desc_index, unsigned char *data, int length)
297{
298 if (pdev == NULL || data == NULL || length < 1)
299 return (LIBUSB20_ERROR_INVALID_PARAM);
300
301 /* put some default data into the destination buffer */
302 data[0] = 0;
303
304 if (libusb20_dev_req_string_simple_sync(pdev, desc_index,
305 data, length) == 0)
306 return (strlen(data));
307
308 return (LIBUSB_ERROR_OTHER);
309}
310
311int
312libusb_get_descriptor(libusb_device_handle * devh, uint8_t desc_type,
313 uint8_t desc_index, uint8_t *data, int length)
314{
315 return (libusb_control_transfer(devh, LIBUSB_ENDPOINT_IN,
316 LIBUSB_REQUEST_GET_DESCRIPTOR, (desc_type << 8) | desc_index, 0, data,
317 length, 1000));
318}