-
Notifications
You must be signed in to change notification settings - Fork 41
/
hid-libusb.c
1438 lines (1232 loc) · 37.6 KB
/
hid-libusb.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// $Id: hid-libusb.c,v 1.6 2018/08/04 22:19:33 karn Exp $
// Modified by KA9Q?
/*******************************************************
HIDAPI - Multi-Platform library for
communication with HID devices.
Alan Ott
Signal 11 Software
8/22/2009
Linux Version - 6/2/2010
Libusb Version - 8/13/2010
FreeBSD Version - 11/1/2011
Copyright 2009, All Rights Reserved.
At the discretion of the user of this library,
this software may be licensed under the terms of the
GNU General Public License v3, a BSD-Style license, or the
original HIDAPI license as outlined in the LICENSE.txt,
LICENSE-gpl3.txt, LICENSE-bsd.txt, and LICENSE-orig.txt
files located at the root of the source distribution.
These files may also be found in the public source
code repository located at:
http://github.com/signal11/hidapi .
********************************************************/
#ifndef _GNU_SOURCE
#define _GNU_SOURCE /* needed for wcsdup() before glibc 2.10 */
#endif
/* C */
#include <stdio.h>
#include <string.h>
#if defined(linux)
#include <bsd/string.h>
#endif
#include <stdlib.h>
#include <ctype.h>
#include <locale.h>
#include <errno.h>
/* Unix */
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/utsname.h>
#include <fcntl.h>
#include <pthread.h>
#include <wchar.h>
/* GNU / LibUSB */
#include <libusb-1.0/libusb.h>
#include "iconv.h"
#include "hidapi.h"
#if __APPLE__
#include "misc.h" // to get barrier stuff
#endif
#ifdef __cplusplus
extern "C" {
#endif
#ifdef DEBUG_PRINTF
#define LOG(...) fprintf(stderr, __VA_ARGS__)
#else
#define LOG(...) do {} while (0)
#endif
#ifndef __FreeBSD__
#define DETACH_KERNEL_DRIVER
#endif
/* Uncomment to enable the retrieval of Usage and Usage Page in
hid_enumerate(). Warning, on platforms different from FreeBSD
this is very invasive as it requires the detach
and re-attach of the kernel driver. See comments inside hid_enumerate().
libusb HIDAPI programs are encouraged to use the interface number
instead to differentiate between interfaces on a composite HID device. */
/*#define INVASIVE_GET_USAGE*/
/* Linked List of input reports received from the device. */
struct input_report {
uint8_t *data;
size_t len;
struct input_report *next;
};
struct hid_device_ {
/* Handle to the actual device. */
libusb_device_handle *device_handle;
/* Endpoint information */
int input_endpoint;
int output_endpoint;
int input_ep_max_packet_size;
/* The interface number of the HID */
int interface;
/* Indexes of Strings */
int manufacturer_index;
int product_index;
int serial_index;
/* Whether blocking reads are used */
int blocking; /* boolean */
/* Read thread objects */
pthread_t thread;
pthread_mutex_t mutex; /* Protects input_reports */
pthread_cond_t condition;
pthread_barrier_t barrier; /* Ensures correct startup sequence */
int shutdown_thread;
int cancelled;
struct libusb_transfer *transfer;
/* List of received input reports. */
struct input_report *input_reports;
};
static libusb_context *usb_context = NULL;
uint16_t get_usb_code_for_current_locale(void);
static int return_data(hid_device *dev, unsigned char *data, size_t length);
static hid_device *new_hid_device(void)
{
hid_device *dev = calloc(1, sizeof(hid_device));
dev->blocking = 1;
pthread_mutex_init(&dev->mutex, NULL);
pthread_cond_init(&dev->condition, NULL);
pthread_barrier_init(&dev->barrier, NULL, 2);
return dev;
}
static void free_hid_device(hid_device *dev)
{
/* Clean up the thread objects */
pthread_barrier_destroy(&dev->barrier);
pthread_cond_destroy(&dev->condition);
pthread_mutex_destroy(&dev->mutex);
/* Free the device itself */
free(dev);
}
#if 0
/*TODO: Implement this funciton on hidapi/libusb.. */
static void register_error(hid_device *device, const char *op)
{
}
#endif
#ifdef INVASIVE_GET_USAGE
/* Get bytes from a HID Report Descriptor.
Only call with a num_bytes of 0, 1, 2, or 4. */
static uint32_t get_bytes(uint8_t *rpt, size_t len, size_t num_bytes, size_t cur)
{
/* Return if there aren't enough bytes. */
if (cur + num_bytes >= len)
return 0;
if (num_bytes == 0)
return 0;
else if (num_bytes == 1) {
return rpt[cur+1];
}
else if (num_bytes == 2) {
return (rpt[cur+2] * 256 + rpt[cur+1]);
}
else if (num_bytes == 4) {
return (rpt[cur+4] * 0x01000000 +
rpt[cur+3] * 0x00010000 +
rpt[cur+2] * 0x00000100 +
rpt[cur+1] * 0x00000001);
}
else
return 0;
}
/* Retrieves the device's Usage Page and Usage from the report
descriptor. The algorithm is simple, as it just returns the first
Usage and Usage Page that it finds in the descriptor.
The return value is 0 on success and -1 on failure. */
static int get_usage(uint8_t *report_descriptor, size_t size,
unsigned short *usage_page, unsigned short *usage)
{
unsigned int i = 0;
int size_code;
int data_len, key_size;
int usage_found = 0, usage_page_found = 0;
while (i < size) {
int key = report_descriptor[i];
int key_cmd = key & 0xfc;
//printf("key: %02hhx\n", key);
if ((key & 0xf0) == 0xf0) {
/* This is a Long Item. The next byte contains the
length of the data section (value) for this key.
See the HID specification, version 1.11, section
6.2.2.3, titled "Long Items." */
if (i+1 < size)
data_len = report_descriptor[i+1];
else
data_len = 0; /* malformed report */
key_size = 3;
}
else {
/* This is a Short Item. The bottom two bits of the
key contain the size code for the data section
(value) for this key. Refer to the HID
specification, version 1.11, section 6.2.2.2,
titled "Short Items." */
size_code = key & 0x3;
switch (size_code) {
case 0:
case 1:
case 2:
data_len = size_code;
break;
case 3:
data_len = 4;
break;
default:
/* Can't ever happen since size_code is & 0x3 */
data_len = 0;
break;
};
key_size = 1;
}
if (key_cmd == 0x4) {
*usage_page = get_bytes(report_descriptor, size, data_len, i);
usage_page_found = 1;
//printf("Usage Page: %x\n", (uint32_t)*usage_page);
}
if (key_cmd == 0x8) {
*usage = get_bytes(report_descriptor, size, data_len, i);
usage_found = 1;
//printf("Usage: %x\n", (uint32_t)*usage);
}
if (usage_page_found && usage_found)
return 0; /* success */
/* Skip over this key and it's associated data */
i += data_len + key_size;
}
return -1; /* failure */
}
#endif /* INVASIVE_GET_USAGE */
#ifdef __FreeBSD__
/* The FreeBSD version of libusb doesn't have this funciton. In mainline
libusb, it's inlined in libusb.h. This function will bear a striking
resemblence to that one, because there's about one way to code it.
Note that the data parameter is Unicode in UTF-16LE encoding.
Return value is the number of bytes in data, or LIBUSB_ERROR_*.
*/
static inline int libusb_get_string_descriptor(libusb_device_handle *dev,
uint8_t descriptor_index, uint16_t lang_id,
unsigned char *data, int length)
{
return libusb_control_transfer(dev,
LIBUSB_ENDPOINT_IN | 0x0, /* Endpoint 0 IN */
LIBUSB_REQUEST_GET_DESCRIPTOR,
(LIBUSB_DT_STRING << 8) | descriptor_index,
lang_id, data, (uint16_t) length, 1000);
}
#endif
/* Get the first language the device says it reports. This comes from
USB string #0. */
static uint16_t get_first_language(libusb_device_handle *dev)
{
uint16_t buf[32];
int len;
/* Get the string from libusb. */
len = libusb_get_string_descriptor(dev,
0x0, /* String ID */
0x0, /* Language */
(unsigned char*)buf,
sizeof(buf));
if (len < 4)
return 0x0;
return buf[1]; /* First two bytes are len and descriptor type. */
}
static int is_language_supported(libusb_device_handle *dev, uint16_t lang)
{
uint16_t buf[32];
int len;
int i;
/* Get the string from libusb. */
len = libusb_get_string_descriptor(dev,
0x0, /* String ID */
0x0, /* Language */
(unsigned char*)buf,
sizeof(buf));
if (len < 4)
return 0x0;
len /= 2; /* language IDs are two-bytes each. */
/* Start at index 1 because there are two bytes of protocol data. */
for (i = 1; i < len; i++) {
if (buf[i] == lang)
return 1;
}
return 0;
}
/* This function returns a newly allocated wide string containing the USB
device string numbered by the index. The returned string must be freed
by using free(). */
static wchar_t *get_usb_string(libusb_device_handle *dev, uint8_t idx)
{
char buf[512];
int len;
wchar_t *str = NULL;
wchar_t wbuf[256];
/* iconv variables */
iconv_t ic;
size_t inbytes;
size_t outbytes;
size_t res;
#ifdef __FreeBSD__
const char *inptr;
#else
char *inptr;
#endif
char *outptr;
/* Determine which language to use. */
uint16_t lang;
lang = get_usb_code_for_current_locale();
if (!is_language_supported(dev, lang))
lang = get_first_language(dev);
/* Get the string from libusb. */
len = libusb_get_string_descriptor(dev,
idx,
lang,
(unsigned char*)buf,
sizeof(buf));
if (len < 0)
return NULL;
/* buf does not need to be explicitly NULL-terminated because
it is only passed into iconv() which does not need it. */
/* Initialize iconv. */
ic = iconv_open("WCHAR_T", "UTF-16LE");
if (ic == (iconv_t)-1) {
LOG("iconv_open() failed\n");
return NULL;
}
/* Convert to native wchar_t (UTF-32 on glibc/BSD systems).
Skip the first character (2-bytes). */
inptr = buf+2;
inbytes = len-2;
outptr = (char*) wbuf;
outbytes = sizeof(wbuf);
res = iconv(ic, &inptr, &inbytes, &outptr, &outbytes);
if (res == (size_t)-1) {
LOG("iconv() failed\n");
goto err;
}
/* Write the terminating NULL. */
wbuf[sizeof(wbuf)/sizeof(wbuf[0])-1] = 0x00000000;
if (outbytes >= sizeof(wbuf[0]))
*((wchar_t*)outptr) = 0x00000000;
/* Allocate and copy the string. */
str = wcsdup(wbuf);
err:
iconv_close(ic);
return str;
}
static char *make_path(libusb_device *dev, int interface_number)
{
char str[64];
snprintf(str, sizeof(str), "%04x:%04x:%02x",
libusb_get_bus_number(dev),
libusb_get_device_address(dev),
interface_number);
str[sizeof(str)-1] = '\0';
return strdup(str);
}
int hid_init(void)
{
if (!usb_context) {
const char *locale;
/* Init Libusb */
if (libusb_init(&usb_context))
return -1;
/* Set the locale if it's not set. */
locale = setlocale(LC_CTYPE, NULL);
if (!locale)
setlocale(LC_CTYPE, "");
}
return 0;
}
int hid_exit(void)
{
if (usb_context) {
libusb_exit(usb_context);
usb_context = NULL;
}
return 0;
}
struct hid_device_info *hid_enumerate(unsigned short vendor_id, unsigned short product_id)
{
libusb_device **devs;
libusb_device *dev;
libusb_device_handle *handle;
ssize_t num_devs;
int i = 0;
struct hid_device_info *root = NULL; /* return object */
struct hid_device_info *cur_dev = NULL;
if(hid_init() < 0)
return NULL;
num_devs = libusb_get_device_list(usb_context, &devs);
if (num_devs < 0)
return NULL;
while ((dev = devs[i++]) != NULL) {
struct libusb_device_descriptor desc;
struct libusb_config_descriptor *conf_desc = NULL;
int j, k;
int interface_num = 0;
int res = libusb_get_device_descriptor(dev, &desc);
unsigned short dev_vid = desc.idVendor;
unsigned short dev_pid = desc.idProduct;
res = libusb_get_active_config_descriptor(dev, &conf_desc);
if (res < 0)
libusb_get_config_descriptor(dev, 0, &conf_desc);
if (conf_desc) {
for (j = 0; j < conf_desc->bNumInterfaces; j++) {
const struct libusb_interface *intf = &conf_desc->interface[j];
for (k = 0; k < intf->num_altsetting; k++) {
const struct libusb_interface_descriptor *intf_desc;
intf_desc = &intf->altsetting[k];
if (intf_desc->bInterfaceClass == LIBUSB_CLASS_HID) {
interface_num = intf_desc->bInterfaceNumber;
/* Check the VID/PID against the arguments */
if ((vendor_id == 0x0 || vendor_id == dev_vid) &&
(product_id == 0x0 || product_id == dev_pid)) {
struct hid_device_info *tmp;
/* VID/PID match. Create the record. */
tmp = calloc(1, sizeof(struct hid_device_info));
if (cur_dev) {
cur_dev->next = tmp;
}
else {
root = tmp;
}
cur_dev = tmp;
/* Fill out the record */
cur_dev->next = NULL;
cur_dev->path = make_path(dev, interface_num);
res = libusb_open(dev, &handle);
if (res >= 0) {
/* Serial Number */
if (desc.iSerialNumber > 0)
cur_dev->serial_number =
get_usb_string(handle, desc.iSerialNumber);
/* Manufacturer and Product strings */
if (desc.iManufacturer > 0)
cur_dev->manufacturer_string =
get_usb_string(handle, desc.iManufacturer);
if (desc.iProduct > 0)
cur_dev->product_string =
get_usb_string(handle, desc.iProduct);
#ifdef INVASIVE_GET_USAGE
{
/*
This section is removed because it is too
invasive on the system. Getting a Usage Page
and Usage requires parsing the HID Report
descriptor. Getting a HID Report descriptor
involves claiming the interface. Claiming the
interface involves detaching the kernel driver.
Detaching the kernel driver is hard on the system
because it will unclaim interfaces (if another
app has them claimed) and the re-attachment of
the driver will sometimes change /dev entry names.
It is for these reasons that this section is
#if 0. For composite devices, use the interface
field in the hid_device_info struct to distinguish
between interfaces. */
unsigned char data[256];
#ifdef DETACH_KERNEL_DRIVER
int detached = 0;
/* Usage Page and Usage */
res = libusb_kernel_driver_active(handle, interface_num);
if (res == 1) {
res = libusb_detach_kernel_driver(handle, interface_num);
if (res < 0)
LOG("Couldn't detach kernel driver, even though a kernel driver was attached.");
else
detached = 1;
}
#endif
res = libusb_claim_interface(handle, interface_num);
if (res >= 0) {
/* Get the HID Report Descriptor. */
res = libusb_control_transfer(handle, LIBUSB_ENDPOINT_IN|LIBUSB_RECIPIENT_INTERFACE, LIBUSB_REQUEST_GET_DESCRIPTOR, (LIBUSB_DT_REPORT << 8)|interface_num, 0, data, sizeof(data), 5000);
if (res >= 0) {
unsigned short page=0, usage=0;
/* Parse the usage and usage page
out of the report descriptor. */
get_usage(data, res, &page, &usage);
cur_dev->usage_page = page;
cur_dev->usage = usage;
}
else
LOG("libusb_control_transfer() for getting the HID report failed with %d\n", res);
/* Release the interface */
res = libusb_release_interface(handle, interface_num);
if (res < 0)
LOG("Can't release the interface.\n");
}
else
LOG("Can't claim interface %d\n", res);
#ifdef DETACH_KERNEL_DRIVER
/* Re-attach kernel driver if necessary. */
if (detached) {
res = libusb_attach_kernel_driver(handle, interface_num);
if (res < 0)
LOG("Couldn't re-attach kernel driver.\n");
}
#endif
}
#endif /* INVASIVE_GET_USAGE */
libusb_close(handle);
}
/* VID/PID */
cur_dev->vendor_id = dev_vid;
cur_dev->product_id = dev_pid;
/* Release Number */
cur_dev->release_number = desc.bcdDevice;
/* Interface Number */
cur_dev->interface_number = interface_num;
}
}
} /* altsettings */
} /* interfaces */
libusb_free_config_descriptor(conf_desc);
}
}
libusb_free_device_list(devs, 1);
return root;
}
void hid_free_enumeration(struct hid_device_info *devs)
{
struct hid_device_info *d = devs;
while (d) {
struct hid_device_info *next = d->next;
free(d->path);
free(d->serial_number);
free(d->manufacturer_string);
free(d->product_string);
free(d);
d = next;
}
}
hid_device * hid_open(unsigned short vendor_id, unsigned short product_id, const wchar_t *serial_number)
{
struct hid_device_info *devs, *cur_dev;
const char *path_to_open = NULL;
hid_device *handle = NULL;
devs = hid_enumerate(vendor_id, product_id);
cur_dev = devs;
while (cur_dev) {
if (cur_dev->vendor_id == vendor_id &&
cur_dev->product_id == product_id) {
if (serial_number) {
if (wcscmp(serial_number, cur_dev->serial_number) == 0) {
path_to_open = cur_dev->path;
break;
}
}
else {
path_to_open = cur_dev->path;
break;
}
}
cur_dev = cur_dev->next;
}
if (path_to_open) {
/* Open the device */
handle = hid_open_path(path_to_open);
}
hid_free_enumeration(devs);
return handle;
}
static void read_callback(struct libusb_transfer *transfer)
{
hid_device *dev = transfer->user_data;
int res;
if (transfer->status == LIBUSB_TRANSFER_COMPLETED) {
struct input_report *rpt = malloc(sizeof(*rpt));
rpt->data = malloc(transfer->actual_length);
memcpy(rpt->data, transfer->buffer, transfer->actual_length);
rpt->len = transfer->actual_length;
rpt->next = NULL;
pthread_mutex_lock(&dev->mutex);
/* Attach the new report object to the end of the list. */
if (dev->input_reports == NULL) {
/* The list is empty. Put it at the root. */
dev->input_reports = rpt;
pthread_cond_signal(&dev->condition);
}
else {
/* Find the end of the list and attach. */
struct input_report *cur = dev->input_reports;
int num_queued = 0;
while (cur->next != NULL) {
cur = cur->next;
num_queued++;
}
cur->next = rpt;
/* Pop one off if we've reached 30 in the queue. This
way we don't grow forever if the user never reads
anything from the device. */
if (num_queued > 30) {
return_data(dev, NULL, 0);
}
}
pthread_mutex_unlock(&dev->mutex);
}
else if (transfer->status == LIBUSB_TRANSFER_CANCELLED) {
dev->shutdown_thread = 1;
dev->cancelled = 1;
return;
}
else if (transfer->status == LIBUSB_TRANSFER_NO_DEVICE) {
dev->shutdown_thread = 1;
dev->cancelled = 1;
return;
}
else if (transfer->status == LIBUSB_TRANSFER_TIMED_OUT) {
//LOG("Timeout (normal)\n");
}
else {
LOG("Unknown transfer code: %d\n", transfer->status);
}
/* Re-submit the transfer object. */
res = libusb_submit_transfer(transfer);
if (res != 0) {
LOG("Unable to submit URB. libusb error code: %d\n", res);
dev->shutdown_thread = 1;
dev->cancelled = 1;
}
}
static void *read_thread(void *param)
{
hid_device *dev = param;
unsigned char *buf;
const size_t length = dev->input_ep_max_packet_size;
/* Set up the transfer object. */
buf = malloc(length);
dev->transfer = libusb_alloc_transfer(0);
libusb_fill_interrupt_transfer(dev->transfer,
dev->device_handle,
dev->input_endpoint,
buf,
length,
read_callback,
dev,
5000/*timeout*/);
/* Make the first submission. Further submissions are made
from inside read_callback() */
libusb_submit_transfer(dev->transfer);
/* Notify the main thread that the read thread is up and running. */
pthread_barrier_wait(&dev->barrier);
/* Handle all the events. */
while (!dev->shutdown_thread) {
int res;
res = libusb_handle_events(usb_context);
if (res < 0) {
/* There was an error. */
LOG("read_thread(): libusb reports error # %d\n", res);
/* Break out of this loop only on fatal error.*/
if (res != LIBUSB_ERROR_BUSY &&
res != LIBUSB_ERROR_TIMEOUT &&
res != LIBUSB_ERROR_OVERFLOW &&
res != LIBUSB_ERROR_INTERRUPTED) {
break;
}
}
}
/* Cancel any transfer that may be pending. This call will fail
if no transfers are pending, but that's OK. */
libusb_cancel_transfer(dev->transfer);
while (!dev->cancelled)
libusb_handle_events_completed(usb_context, &dev->cancelled);
/* Now that the read thread is stopping, Wake any threads which are
waiting on data (in hid_read_timeout()). Do this under a mutex to
make sure that a thread which is about to go to sleep waiting on
the condition acutally will go to sleep before the condition is
signaled. */
pthread_mutex_lock(&dev->mutex);
pthread_cond_broadcast(&dev->condition);
pthread_mutex_unlock(&dev->mutex);
/* The dev->transfer->buffer and dev->transfer objects are cleaned up
in hid_close(). They are not cleaned up here because this thread
could end either due to a disconnect or due to a user
call to hid_close(). In both cases the objects can be safely
cleaned up after the call to pthread_join() (in hid_close()), but
since hid_close() calls libusb_cancel_transfer(), on these objects,
they can not be cleaned up here. */
return NULL;
}
hid_device * hid_open_path(const char *path)
{
hid_device *dev = NULL;
libusb_device **devs;
libusb_device *usb_dev;
int res;
int d = 0;
int good_open = 0;
if(hid_init() < 0)
return NULL;
dev = new_hid_device();
libusb_get_device_list(usb_context, &devs);
while ((usb_dev = devs[d++]) != NULL) {
struct libusb_device_descriptor desc;
struct libusb_config_descriptor *conf_desc = NULL;
int i,j,k;
libusb_get_device_descriptor(usb_dev, &desc);
if (libusb_get_active_config_descriptor(usb_dev, &conf_desc) < 0)
continue;
for (j = 0; j < conf_desc->bNumInterfaces; j++) {
const struct libusb_interface *intf = &conf_desc->interface[j];
for (k = 0; k < intf->num_altsetting; k++) {
const struct libusb_interface_descriptor *intf_desc;
intf_desc = &intf->altsetting[k];
if (intf_desc->bInterfaceClass == LIBUSB_CLASS_HID) {
char *dev_path = make_path(usb_dev, intf_desc->bInterfaceNumber);
if (!strcmp(dev_path, path)) {
/* Matched Paths. Open this device */
/* OPEN HERE */
res = libusb_open(usb_dev, &dev->device_handle);
if (res < 0) {
LOG("can't open device\n");
free(dev_path);
break;
}
good_open = 1;
#ifdef DETACH_KERNEL_DRIVER
/* Detach the kernel driver, but only if the
device is managed by the kernel */
if (libusb_kernel_driver_active(dev->device_handle, intf_desc->bInterfaceNumber) == 1) {
res = libusb_detach_kernel_driver(dev->device_handle, intf_desc->bInterfaceNumber);
if (res < 0) {
libusb_close(dev->device_handle);
LOG("Unable to detach Kernel Driver\n");
free(dev_path);
good_open = 0;
break;
}
}
#endif
res = libusb_claim_interface(dev->device_handle, intf_desc->bInterfaceNumber);
if (res < 0) {
LOG("can't claim interface %d: %d\n", intf_desc->bInterfaceNumber, res);
free(dev_path);
libusb_close(dev->device_handle);
good_open = 0;
break;
}
/* Store off the string descriptor indexes */
dev->manufacturer_index = desc.iManufacturer;
dev->product_index = desc.iProduct;
dev->serial_index = desc.iSerialNumber;
/* Store off the interface number */
dev->interface = intf_desc->bInterfaceNumber;
/* Find the INPUT and OUTPUT endpoints. An
OUTPUT endpoint is not required. */
for (i = 0; i < intf_desc->bNumEndpoints; i++) {
const struct libusb_endpoint_descriptor *ep
= &intf_desc->endpoint[i];
/* Determine the type and direction of this
endpoint. */
int is_interrupt =
(ep->bmAttributes & LIBUSB_TRANSFER_TYPE_MASK)
== LIBUSB_TRANSFER_TYPE_INTERRUPT;
int is_output =
(ep->bEndpointAddress & LIBUSB_ENDPOINT_DIR_MASK)
== LIBUSB_ENDPOINT_OUT;
int is_input =
(ep->bEndpointAddress & LIBUSB_ENDPOINT_DIR_MASK)
== LIBUSB_ENDPOINT_IN;
/* Decide whether to use it for intput or output. */
if (dev->input_endpoint == 0 &&
is_interrupt && is_input) {
/* Use this endpoint for INPUT */
dev->input_endpoint = ep->bEndpointAddress;
dev->input_ep_max_packet_size = ep->wMaxPacketSize;
}
if (dev->output_endpoint == 0 &&
is_interrupt && is_output) {
/* Use this endpoint for OUTPUT */
dev->output_endpoint = ep->bEndpointAddress;
}
}
pthread_create(&dev->thread, NULL, read_thread, dev);
/* Wait here for the read thread to be initialized. */
pthread_barrier_wait(&dev->barrier);
}
free(dev_path);
}
}
}
libusb_free_config_descriptor(conf_desc);
}
libusb_free_device_list(devs, 1);
/* If we have a good handle, return it. */
if (good_open) {
return dev;
}
else {
/* Unable to open any devices. */
free_hid_device(dev);
return NULL;
}
}
int hid_write(hid_device *dev, const unsigned char *data, size_t length)
{
int res;
int report_number = data[0];
int skipped_report_id = 0;
if (report_number == 0x0) {
data++;
length--;
skipped_report_id = 1;
}
if (dev->output_endpoint <= 0) {
/* No interrput out endpoint. Use the Control Endpoint */
res = libusb_control_transfer(dev->device_handle,
LIBUSB_REQUEST_TYPE_CLASS|LIBUSB_RECIPIENT_INTERFACE|LIBUSB_ENDPOINT_OUT,
0x09/*HID Set_Report*/,
(2/*HID output*/ << 8) | report_number,
dev->interface,
(unsigned char *)data, length,
1000/*timeout millis*/);
if (res < 0)
return -1;
if (skipped_report_id)
length++;
return length;
}
else {
/* Use the interrupt out endpoint */
int actual_length;
res = libusb_interrupt_transfer(dev->device_handle,
dev->output_endpoint,
(unsigned char*)data,
length,
&actual_length, 1000);
if (res < 0)
return -1;
if (skipped_report_id)
actual_length++;
return actual_length;
}
}
/* Helper function, to simplify hid_read().
This should be called with dev->mutex locked. */
static int return_data(hid_device *dev, unsigned char *data, size_t length)
{
/* Copy the data out of the linked list item (rpt) into the
return buffer (data), and delete the liked list item. */
struct input_report *rpt = dev->input_reports;
size_t len = (length < rpt->len)? length: rpt->len;
if (len > 0)
memcpy(data, rpt->data, len);
dev->input_reports = rpt->next;
free(rpt->data);
free(rpt);
return len;
}
static void cleanup_mutex(void *param)
{
hid_device *dev = param;
pthread_mutex_unlock(&dev->mutex);
}
int hid_read_timeout(hid_device *dev, unsigned char *data, size_t length, int milliseconds)